Author Topic: What can be done to improve the performance of clandestine nitroethane synth?  (Read 35285 times)

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rev drone

  • Guest
Howdy y'all,

For those living in the heart of the nastiest drug-crazed nation on Earth, nitroethane is hard to aquire. This means a person has to eithe do without (*sigh*), or make their own. After looking at the methods on Rhodium's page, I came to the resoundint conclusion that none of the methods were too great. Now there have been a lot of advacements in Sn2 reactions, especially related to PTC technology. And all these advancements have far outstripped published practical applications. Question: does anyone have any ideas as to how to improve the reaction conditions between diethylsulfate and sodium nitrite?

------------------
-the good reverend drone


rev drone

  • Guest
Specificly, can anyone think of a PTC that would be good at efficiently transfering nitrosyl ions into Et2O or some other fairly inert non-polar solvent?

------------------
-the good reverend drone


rev drone

  • Guest
What about using DMF or DMSO as the solvent in conjugation with diethylsulfate and NaNO2? By actually having the components in solution with each other, it would seem yields could be greatly inceased. Diethyl sulfate is cheap, cheap, cheap; it'd sure be nice to get good yields with it too.

I'll stop responding to my own post now,

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-the good reverend drone


ymir

  • Guest
A perusal of the original JCS article leads to some observations from the discussion portion, which isn't on Rhodium's page: this method is based on the work of Krause, [D. R. P. 294,755 (1916)] producing the salt, sodium ethyl sulfate which is worked up to yield nitroethane. It's mentioned that dilution leads to more nitrous fumes being produced (leading to ethyl nitrite), lowering the yield of nitroethane. A good shaker is required. Loki reports that a vari-speed belt massager is easily converted into a high powered laboratory shaker. Another old route to nitroethane is described in Industrial and Engineering Chemistry, Vol. 28,March 1936 pp 339=344. This method involves vapor phase nitration of paraffins, producing 26% nitroethane from propane, and at least 80% from ethane. In essence the procedure bubbles the paraffin gas through nitric acid heated to 108 degrees centrigrade. The gaseous mixture is then led through a reactor heated to 420 degrees centrigrade, condensed, and fractionated. In the article, Hass et al state that superatmospheric pressure increased the yield somewhat, and that aluminum nitrate, glass, and stainless steel produced no catalytic effect. Silica gel and platinum promoted oxidation instead of nitration. If an effective catalyst could be found, a simple tube furnace could be substituted for the eutetic salt heated tubing reactor. Perhaps some members of the Hive with easy access to a real chemistry library could research nitration catalysts.

Ritter

  • Guest
The simplest and highest yielding procedure to hit the underground literature is posted in TSII by yours truly.  The method uses phloroglucinol to scavenge detrimental nitrous compounds during the Sn2 rctn. between NaNO2 and an alkyl halide in a polar aprotic solvent.  A post showed up a few months ago here on the boards describing the failure of NaNO2 and ethyl bromide in a polar aprotic solvent (DMF,DMSO and n-Methylpyrolidinone) to form nitroethane. 

I must reccomend my synthesis over any dealing with diethylsulfate due to the inherently poisonous nature of this nasty chemical warfare agent.  Face it, ordering any hazardous chemicals let alone known poisons is a risk.  People must realize that a whole new governmental agency is being added to the loop of hazards involved w/ obtaing needed reagents.  The DOT is made aware of each and every shipment of those boxes with the pretty rotated square placard sticker stickers which say things like corrosive, poison, reactive w/ water, dangerous-you get the idea.  Diethyl sulfate is such a toxic material that inquiries may be made over why such a toxic material was requested by a venue.

Ritters nitroethane synth is by far the best because ordering needed ragents will not arouse suspicion for any reason.  You sure can't say that about diethylsulfate.  The only drawback from the described synth is the price of phloroglucinol, however a simple NaOH wash of the rctn products will separate all glucinol to allow regeneration for another batch.  It can be used over and over.

This method often yields over 90% and literature citings are provided to back these claims.  Check it out!


ymir

  • Guest
Phlorglucinol is prepared by fusion of resorcinol with caustic soda and decomposition of the melt with acid. Since phlorglucinol is over five times as expensive as resorcinol, some bees may prefer to make it. Most uses are medical. Few procedures are benign enough to be performed in the kitchen, most require a laboratory quality fume hood and or glove box.  Diethyl sulfate is very toxic and hazardous, and should be handled in a hood with gloves.

Osmium

  • Guest
Don't think that wearing rubber gloves will protect you whatever happens. Once that shit is spilled over the gloves, it's time to change and discard them. NOW! Not in 2hrs, now! This is true for most other solvents and chems. You can't put your gloved hand into a barrel of stuff and expect them not to leak after a few seconds. Don't want to frighten anybody, but that's the way it is. Wearing gloves does not mean you are safe and can do whatever you want!

Alchemy

  • Guest
Hi
If Sodium Nitrite is controled where
You live(carcinogen) there is a good
method from sodiumnitate and Pb(lead)
described in W.T.Cooke "The Laboratory Preparation of Sodium Nitrite"
Australian chem. Inst. J Proc.
Vol.11(1944)49-51
Sincerely
Alchemy

Snotbrain

  • Guest
Just a small note to these procedings:

A great, variable shaker can be obtained from the use of the water bed vibrators, or the gizmoes that vibrate your bed for 25 cents in cheap motels.

Not that I've ever been in any cheap motels: I'm way to classy for that. (Yeahrite)

Two variable speed vibrators can make the old oscillating sander trick look pretty tame: as you adjust their harmonic interactions!

snodder


spitball

  • Guest
Goddammit! I've been looking for a bed vibrator for years! Where,son, where did you find such an awesome commodity????

-spitball-

oh, and another thing that the fabulous Rev.Drone envisioned, was using one of those 'fat jigglers' from the 50's - 60's( you know, the belts on the machnine that shakes you back and forth?) to vibrate a large vessel...


ymir

  • Guest
Industrial quality gloves are needed for things like diethyl sulfate. North makes a good product. It turns out that if phenol is fused with caustic soda; pyrocatchetol, resorcinol and phlorglucinol are formed (Ber. 12, 417 Post 1879 (not existing)). After seperation, the pyrocatchetol is saved for future use(see TSII for details), the resorcinol is fused with caustic soda, and acidified, producing more phlorglucinol. Phenol(carbolic acid) is very cheap and easily available. A large crucible would be helpful in this matter, though there may be substitutes. Separation could be a problem, Loki wonders if column chromatography might be superior to fractional distillation. Also, use of a tube furnace doesn't appear to be a good idea for vapor-phase nitration. The reaction is exothermic, and works best at the higher operating temperature. Contact time can be as little as a fraction of second at the higher temperatures. An excess of the hydrocarbon is used to serve as a heat sink to prevent explosions. Catalysts used are oxygen and bromine/chlorine, with the nitric acid/oxygen/bromine molar ratio being 1/2/.003. Those who are interested should look at JOC 17, 906-944 for more info. While this method is certainly the cheapest in terms of materials (propane!), the equipment could be very expensive, unless fabricated by a MacGyver type. The diethyl sulfate/sodium nitrite method would be second cheapest as far as materials, not as equipment intensive (Loki thinks he could hook up 4 gallon jugs to his shaker!) as vapor phase nitration, but involve a very hazardous material, and some obnoxious by products as well (nitrous acid and nitrite esters venting). Ritter's related method is not nearly as expensive as it first sounds, with phenol costing around $75/gal. If the total yield was only around 25%, that would still make it about $100/kg, far less than it sells for. For the average chemist, Ritter's method looks to be the best.

Snotbrain

  • Guest
Youse can dredge them up at a waterbed store for about $30 bux. 

Damn: even FINDING a waterbed store these days is trick: seems to be a vanishing  commodity.

snodder


ymir

  • Guest
Organic Reactions 12, p 110 reveals an interesting fact about the sodium nitrite/alkyl halide synthesis of nitroparaffins: catechol and resorcinol share the nitrite ester scavenging effect of phlorglucinol. Obviously, this means that in the synthesis in Ber. 11, 1332(1878) & 12, 417 (1879) which produces these three compounds from phenol, purification is probably not absolutely necessary. Kornblum (JACS 78, 1497-1501) reports that colored impurties result when these two compounds are used, and also that ethylene glycol can work as a solvent. Perhaps something as simple as Norit could remove these impurities. Nitroparaffins were purified by Pearson for use in kinetic studies by drying with magnesium sulfate, refluxing with urea, drying with phosphorus pentoxide, and distillation through a 10-plate column. Turnbull and Maron purified nitroparaffins by treatment with urea, sodium sulfate, and low temperature distillation. The vapor phase nitration has been done in small diameter tube reactors, fluidized bed reactors, and molten salt reactors according to Kirk-Othmeyer. No specific reference is given for the tube reactors, further library investigation is needed.

Ritter

  • Guest
Ymir,

Where did you come from anyway?  Your posts are always meticulously researched and have helped many here!  We greatly appreciate all the time and effort you devote to researching all of these amazing references!  Thanks so much for all of your input!!!!!!!!!!!!

Ritter


ymir

  • Guest
My mama, like all bees! What the bees, or almost all other scientists for that matter, don't realize is the importance of 'old' chemistry. This science, for all practical purposes, began in Germany several hundred years ago. If this is hard to believe, just consider the terminology: Fischer projection, Bunsen burner, Liebig condenser and Erlenmeyer flask. The rest of the world followed suit. Thus a search for the truth must include searching all windows to the literature. Some very fine general works of reference have been published over the years, such as Kirk-Othmeyer and Thorpe's. Now, new science is very interesting and useful, but old science can be applied to current problems that didn't exist when it was published. Certainly, Drone's idea about using PTC catalysts may be very useful in this matter. Experimentation by those with the proper equipment is required to determine the truth! Ethylene glycol will probably not be as good as a solvent as DMSO/DMF, and will require the use of urea, but it, along with phlorglucinol synthesis from phenol, does allow for cost effective scalability. It seems that that these three paths will make piperonal more useful, as making black pepper a controlled substance might not wash with the public. As more and more paths become known, the sooner the control freaks will be overthrown!

ymir

  • Guest
The reference in which a small diameter aluminum tubular reactor was used to nitrate paraffins is Chem. Eng. 73,(12) 149 (1966). Pressures between 8 and 12 atmospheres are most effective. Any catalyst would have to promote the free radical reaction mechanism. Some references not given already are JACS 62, 2885 (1936) & 66 2017(1944) and Ind. Eng. Chem. 30, 67(1938); 31, 648(1939); 32, 427(1940); 34, 400(1942) & 41, 2266(1949). In the alkyl halide method(modified Meyer synthesis), urea is used to increase the solubility of sodium nitrite. Ethylene glycol is inferior as a solvent, but can be made to work. This reaction, and the related methods based on sodium ethyl sulfate, both work as a nucleophilic replacement at carbon by nitrite. Any experiments with phase transfer catalysts would have to be compatible with this reaction mechanism. One thing that should be obvious, but apparently isn't is the use of the nitrite ester scavanging phlorglucinol with the diethyl sulphate/sodium nitrite reaction. Both of these reactions work by the same mechanism, and ester formation needs to be suppressed to maximize yield. This may well increase the yield of the synthesis that this thread was started about.

rev drone

  • Guest
Hm, a heated, 8-12 atm vapor phase nitration of ethane? Doesn't that strike you as a tad impractical? I must say, even with the extensive resources that some of the elite bees here have, I could not see a "clandustrial" application utiizing such conditions any time in the near future.

Ho-hum; perhaps Ritter's method is best, though I still don't see any advantage in ethyl bromide over diethyl sulfate. Ethyl bromide is poisonous, carbinogenic, and will arrive at your door with just as many HazMat stickers. I agree EtBr's smell is MUCH nicer, but both of them should only be used under a fume hood.

I never heard of diethyl sulfate being used as a chemical warfare agent. This is a major industrial chemical; there's nothing obscure about it. Then again, during WWI they threw everything but the kitchen sink at each other.

------------------
-the good reverend drone


ymir

  • Guest
Actually, these references are about nitration of propane, resulting in a mixture of nitroparaffins, including nitromethane and nitroethane. Propane is really inexpensive. Definitely not for the average chemist, but for those with the McGyver animus...

Rhodium

  • Guest
This sounds like an interesting thread. I ESPECIALLY would like someone to fetch the reference mentioned in

Post 103085

(Alchemy: "Re: What can be done to improve the performance of clandestine nitroethane synth?", Chemistry Discourse)
.

Aurelius

  • Guest
here's what available on the hive, thus far:

Nitroethane synthesis: a compilation

Method 1: from sodium ethyl sulfate and a metal nitrite

1.5 mole sodium nitrite (103.5g) is intimately mixed with 1 mole of sodium ethyl sulfate (158g) and 0.0625 moles of K2CO3 (8.6g). The mixture is then heated to 125-130°C, at which temperature the nitroethane distills over as soon as it is formed. The heating is discontinued when the distillation flow slackens considerably, and the crude nitroethane is washed with an equal amount of water, dried over CaCl2, and if needed, decolorized with a little activated carbon. The nitroethane is then re-distilled, collecting the fraction between 114-116°C. Yield 46% of theory

(another ref says max. 42%)
Chemical Abstracts, Vol 49, pg 836.

Method 2: from diethyl sulfate and sodium nitrite

Initial run - Into a stoppered bottle was placed a mixture of diethyl sulfate (120g) and sodium nitrite solution (120g in 160ml of water.) The bottle was shaken mechanically for 20 hours, the pressure being released at intervals. The contents were then poured into a separating funnel, and the upper layer separated, dried over calcium chloride. and distilled at 14 mmHg, the distillate up to 60°C being collected (the residue, ca. 230g., consisted of ethyl sulphate and was used again). The distillate was fractionated at atmospheric pressure, and the fraction of bp 114-116°C collected. This was shaken with water, dried over calcium chloride, run through charcoal, and redistilled; bp 114-115.5°C. Yield, 17.7g. (31%, or allowing for recovered ethyl sulfate, 43.5%).

    Routine run - A second experiment was then carried out using the same quantity of ethyl sulfate as above. The recovered nitrite solution (lower layer) from the first run was concentrated by adding approximately 16 g. of sodium nitrite per 160ml of solution. Yield 26.4g (46%, or allowing for recovered ethyl sulphate, 65%). For each additional subsequent run approximately 16 g. of nitrite per 160 ml of solution were added, although this represents a rather diminishing concentration in view of the increased yield of nitroethane


Method 3: from ethyl bromide (iodide) and sodium nitrite (dmf)
32.5 grams of ethyl bromide (0.3 moles) was poured into a stirred solution of 600ml dimethylformamide and 36 grams dry NaNO2 (0.52 mole) in a beaker standing in a water bath keeping the solution at room temperature as the reaction is slightly exothermic. Always keep the solution out of direct sunlight. The stirring was continued for six hours. After that, the reaction mixture was poured into a 2500 ml beaker or flask, containing 1500 ml ice-water and 100 ml of petroleum ether. The petroleum ether layer was poured off and saved, and the aqueous phase was extracted four more times with 100 ml of petroleum ether each, where after the organic extracts were pooled, and in turn was washed with 4x75ml of water. The remaining organic phase was dried over magnesium sulfate, filtered, and the petroleum ether was removed by distillation under reduced pressure on a water bath, which temperature was allowed to slowly rise to about 65°C. The residue, consisting of crude nitroethane was distilled under ordinary pressure (preferably with a small distillation column) to give 60% of product, boiling at 114-116°C.
 
 The ethyl bromide reacts with NaNO2, forming nitroethane and ethyl nitrite.
This method can be varied in a few ways. Firstly, dimethyl sulfoxide (DMSO) can be substituted for the dimethylformamide (DMF) as solvent. Ethylene glycol also works as solvent, but the reaction proceeds pretty sluggishly in this medium, allowing for side reactions, such as this: RH-NO2 + R-ONO => R-(NO)NO2 + R-OH. KNO2 can also be used instead of NaNO2. If NaNO2 is used in DMF, 30g (0.5 mol) of urea can also be added as nitrite scavenger to minimize side reactions, as well as simultaneously increasing the solubility of the NaNO2 and thereby significantly speeding up the reaction.

           If the ethyl bromide is substituted with ethyl iodide, the required reaction time is decreased to only 2.5 h instead of 6 h. In case ethyl iodide is employed, a slight change in the above procedure needs to be done. The pooled pet ether extracts should be washed with 2x75ml 10% sodium thiosulfate, followed by 2x75ml water, instead of 4x75ml water as above. This to remove small amounts of free iodine

Method 4 : from ethyl halide and silver nitrite

Cool 100 g of silver nitrite (0.65 mol) in 150 ml of dry ether to 0°C in a 3 neck 500 ml flask (in a darkened room or using yellow light). Add 0.5 moles of ethyl halide (78g ethyl iodide or 55g of ethyl bromide) dropwise over a 2 hour period while stirring constantly and maintaining the temperature at 0°C and dark conditions. Stir for 24 hours at 0°C, then 24 hours at room temp if using ethyl bromide, and 48h if using ethyl bromide. (Test for halogens to see when the reaction is completed, through adding a few drops of the reaction mixture to a test tube containing an alcoholic solution of silver nitrate and note if a precipitate appears. If so, the reaction is not complete. The Beilstein test can also be used, it uses a small coil of copper wire in a test tube to which a small portion of the reaction mixture is added and it is noted if reaction occurs, where elemental silver will deposit on the surface of the copper coil.) Silver iodide (or bromide) will precipitate in the solution during the course of the reaction. Filter off the silver salt, and wash it with several portions of ether. Evaporate the ether at room temperature. (This may be substituted with distillation of the ether using a water bath at atmospheric pressure. A 2x45 cm column packed with 4 mm pyrex helices is used. A more efficient column is not used due to the instability of the ethyl nitrite formed as a by-product in the reaction. Maintain anhydrous conditions since the ethyl nitrite will hydrolyze to ethanol and will be difficult to separate.) Then vacuum distill the residue at about 5 mmHg. The ethyl nitrite will be the initial fraction, followed by an intermediate fraction, then the nitroethane will distill. The yield is about 83% of theory


Method 5: oxidation of ethyl amine with peracids  (m-perbenzoicacid)

General Procedure for the Oxidation of Primary & Secondary amines using m-chloroperbenzoic acid.

m-Chloroperbenzoic acid (4.1g, 0.02mol, 85% pure) is dissloved in 30 mls of 1,2-dichloroethane in a three-neck flask equipped with a condenser and a pressure-equalising dropping funnel. The amine (0.005 mol) in 3-5 mls of 1,2-dichloroethane solvent is added drop-wize to the refluxing m-Chloroperbenzoic acid/1,2-dichloroethane solution. Refluxing temperature 83oC for 3 hours.
After the addition of the amine and refluxing time, the reaction mixture is cooled, filtered and washed with three 50 ml portions of 1M sodium hydroxide solution and dried over anhydrous magnesium sulphate. The removal of the 1,2-dichloroethane solvent by distillation (rotary) gives a crude nitroalkane. Purification of the crude crude nitroalkane with vacuum distillation. Yields vary, approx 62 %.

Oxidation of n-propylamine and higher alkane amines give nitroalkane at approx 62 %.

[Note] Nitromethane and nitroethane form sodium water-soluable salts with 1M sodium hydroxide solution

Method 6: oxidation of ethyl amine with potassium permanganate
Perhaps by the method in Org Synth CV 5, 845. 

   REFS for methods 5 + 6:


Chem.Ber. (1902) 35, 4294
Eur.J.Med.Chem. (1991) 26, 2, 167-178
Eur.J.Org.Chem. (1998) 4, 679-682
Heterocycles (1998) 48, 1, 181-185
J.Amer.Chem.Soc. (1954) 76, 4494
J.Amer.Chem.Soc. (1956) 78, 4003
J.Amer.Chem.Soc. (1957) 79, 5528
J.Chem.Soc.Chem.Commun. (1995) 15, 1523-1524
J.Org.Chem. (1960) 25, 2114-2126
J.Org.Chem. (1979) 44, 659-661.
J.Org.Chem. (1992) 57, 25, 6759-6764
J.Org.Chem. (1993) 58, 5, 1118-1121
Magn.Reson.Chem. (1997) 35, 2, 131-140
Org.Synth. (1963) 43, 87
Tetrahedron (1991) 47, 28, 5173-5184
Tetrahedron (1995) 51, 41, 11305-11318
Tetrahedron Lett. (1981) 22, 18, 1655-1656
Tetrahedron Lett. (1986) 27, 21, 2335-2336
Tetrahedron Lett. (1996) 37, 6, 805-808
Z.Naturforsch.B (1989) 44, 11, 1475-1478

Method 7:  destructive distillation of alpha-bromopropionic acid with sodium nitrite

   K2CO3 + NaNO2 + H2O + a-br-propionic acid ? nitroethane 50%yield

   Add 20g of the acid to a solution of K2CO3 in the amount of base that causes the solution to be basic to phenolphthalein.  The add 20g of NaNO2—there should be approx. 100ml of solution.  Place in a 250ml rb flask and distill quickly- the first 100ml will come over before the rxn takes place.  Then the nitroethane comes over. Distill until no more product comes over.  (don’t distill to dryness) 

V. Auger. Bull. Soc. Chim. France  Post no. 3, 23, 333 (1900) by the kolbe method.

Method 8:  oxidation of ethyl amine to nitroethane with dimethyldioxirane

    A new synthesis of nitro compounds using dimethyldioxirane(DMDO)
Tetrahedron Letters,Vol.27,No.21,pp 2335-2336,1986

Abstract: Dimethyldioxirane oxidizes primary amines to nitro compounds in a facile, mild, high yield process.

Here we report that aliphatic and aromatic primary amines are rapidly and efficiently oxidized to nitro compounds by dimethyldioxirane, DMDO. Indeed a survey of some general methods for the preparation of nitro compounds (2) suggests to us that the use of DMDO may be the method of choice. The conditions used are exceedingly mild and give the nitro compound as a solution in acetone. Table 1 summarizes our results with some representative amines.

Table 1. Oxidation of amines with Dimethyldioxirane(DMDO).
Amine            Product           Yield    (Product m.p.(C)
~~~~~~~~~~~~~~~~~~~~~~~--~~~~~~--~---~~~~~~~~~~~--
Aniline           Nitrobenzene        91
p-Anisidine       p-Nitroanisole      94            54
n-Butylamine      1-Nitrobutane       84
sec-Butylamine    2-Nitrobutane       81
tert-Butylamine   2-Methyl-2-nitrobut 90
1-Aminoadamantane 1-Nitroadamsntane   95            159
Cyclohexylamine   Nitrocyclohexane    95
trans-Azobenzene  Axoxybenzene        96            36

In a typical reaction n-butylamine (0.052g; 0.7 mmol) in 5 ml of acetone was treated with 95 ml of DMDO, in acetone solution (ca 0.05M)(4) The solution was kept at room temperature for 30 min. with the exclusion of light. Analysis of the reaction mixture by capillary GC indicated the presence of l-nitrobutane only. The oxidations are believed to occur by means of successive oxidations by,1. In the aniline case the blue color of the nitroso conpound is observed immediately upon adding the solution of DMDO. In separate experiments we have shown that both phenylhydroxylamine and nitrosobenzene are readily oxidized to nitrobenzene by DMDO. The blue color of intermediate nitroso compound was observed in all of the amine oxidations.

Dimethyldioxirane is a powerful oxygen atom donor, which oxidizes a variety of substrates 'including hydrocarbons'. Work is continuing on the oxidation of nitrogen-containing compounds by DMDO.

1. Chemistry of Dioxiranes. 5. Paper 4 of this series is J. Am. Chem. Soc., in press (1986).
2. H.O. Larson in The Chemistry of the Nitro and Nitroso Groups, H. Feuer, Ed., J. Wiley and Sons. N.Y. 1969.
4. The concentration of,DMDO in acetone was determined by titrating an aliquot with phenyl methyl sulfide. The synthesis of DMDO has been described (5).
5. R.W. Murray and R. Jeyaraman, J. Org. Chem., (50) 2847 (1985).
Dioxiranes:  synthesis and reactions of methyldioxiranes.
J. Org. Chem.  (1985),  50(16),  2847-53.

Abstract
The peroxymonosulfate-acetone system produces dimethyldioxirane under conditions permitting distn. of the dioxirane from the synthesis vessel.  The same conditions were used to prep. other methyldioxiranes.  Solns. of dimethyldioxirane prepd. in this manner were used to study its chem. and spectroscopic properties.  The caroate-acetone system was also used to study the chem. of in situ generated dimethyldioxirane.  cis- And trans-stilbenes were converted stereospecifically to the corresponding epoxides with dimethyldioxirane in acetone

Method 9:  isomerization of ethyl nitrite to nitroethane over asbestos catalyst

   J. Chem. Soc. 109, 701 (1916)
   (pass over asbestos in a tube furnace @ 120-130*C for best results/best yield)

Method 10: ethyl bromide, DMSO, NaNO2 and phloroglucinol dihydrate

   By Ritter, in Strike’s book- TSII.

   32g or 26ml EtBr is poured into 250ml of DMSO with 36g NaNO2 and 52g phloroglucinol already present in solution.  (Pglucinol is expensive but can be recycled) put on good mag. stirring and stopper the flask.  Stir for two hours in emulsion form, then dump into a 600ml of ice water and extract twice with DCM. (2x200ml)   dry the extracts with  MgSO4 or CaCl2 the evap off the DCM.  Distill and collect the fraction from 113-116*C--- yields about 20g of nitroethane (80%)  (another ref say maybe over 90% consistently)

Other notes:  catechol and resorcinol have the same nitrite scavenging abilities as phloroglucinol.  And ethylene glycol can be used as a solvent.  A simple NaOH wash of the final solution (nitroethane removed) will give the sodium salt of your phloroglucinol catalyst.  Acidification of the solution will precip the catalyst for recovery by filtration.

JACS 79, 2507 (1957)
Tetrahedron vol 46, No 21, pp 7443-57 (1990)
Ber. 11, 1332 (1878)
Ber. 12, 417 (1879)
JACS, Vol 78, 1497-1501

Method 11:  3-chloropropionic acid sodium salt, and NaNO2

   ClCH2CH2COONa + NaNO2 ? NO2CH2CH2COONa + NaCl

   NO2CH2CH2COONa + H2O –heat?  NO2CH2CH3 + NaHCO3

Modification of Nitromethane synthesis from Organic Synthesis, Vol? Pg 401.

Method 12:  most complicated synth

   CH3CH=NOH  + Cl2 ? CH3CH (Cl)(NO)   (? gem-chloronitrosoethane)

   Gem-comp + O3 ? CH3CH (Cl)(NO2)

   CH3CH (Cl)(NO2) + NaOH + H2 + Pd/C ? nitroethane (50%) + HCl

JOCS, Vol 41, pg 733-735 (1976)

Method 13:  electrochemical oxidation ---- not possible by method below

   Ethyl amine is oxidized to methyl nitrile in anhydrous solvent.  In the presence of water it is oxidized to the imine, then acetaldehyde which is further oxidized to acetic acid.

Method 14:  Vapor Phase nitration of propane.

   The propane is bubbled through nitric acid heated to 108*C and lead into a reactor at 420*C.  the product is then condensed and fractionated.  (26% nitroethane formed)

Industrial and Engineering Chemistry, Vol 28, Mar, 1936. Pg 339-344.
JOC, Vol 17, pg 906-944.

Method 15:  Vapor Phase nitration of ethane.

Same as propane but at least 80% yields. 

Industrial and Engineering Chemistry, Vol 28, Mar, 1936. Pg 339-344.
JOC, Vol 17, pg 906-944.

Method 16:  Vapor Phase Nitration of Ethanol using Group II oxides or halides as a catalyst (works for methanol and propanol too)

US pat # 4431842

Method 17: Distillation of alpha-bromopropionic acids with NaNO2 in the presence of Magnesium Sulfate in DMSO

US pat # 4319059

(the alpha-bromo acid can be obtained using propionic acid in the procedure from Org. Synth. CV 1, 115.)


Method 18:  Oxidation of alanine with permanganate followed by decarboxylation

Nitroethane via oxidation of alanine? 
 
 Theory
------
MeCH(NH2).COOH + 3(O) --> MeCH(NO2).COOH + H2O.
MeCH(NO2).COOH + NaOH --> MeCH(NO2).COONa.
MeCH(NO2).COONa + H2O --> MeCH2(NO2) + NaHCO3.
Procedure
---------
A solution of potassium permanganate (0.3 mol) in water was made by dissolving 47.41 g KMnO4 in 400 mL hot water in a 1 L 3-necked flask fitted with a reflux condenser, a stirbar[note 1], thermometer, and a 100-mL addition funnel. As the solution cools to room temperature fine crystals of KMnO4 crystallise out of solution[note 2]. A solution of alanine (0.1 mol, 8.91 g) in 65 mL of water was placed in the addition funnel and added dropwise with stirring over a 20 minute period. The temperature slowly rose. When the addition was complete, the reaction mixture was heated to 60º over a period of approximately 2 hours. 40 mL of acetone was added [note 3] and then the reaction mixture maintained at 70-85º [the sludge was extremely viscous and the stirbar was of no use] for 2 hours. 0.1 mol sodium hydroxide in 20 mL of water was then added through the addition funnel.
Pause (to be completed).
-----
The flask showed no sign of heating up after addition of the NaOH. By now the black/brown sludge will not mix (with the stir-bar). The next step is to heat to 80-100C to decarboxylate any nitro-propionic acid and then to steam distil.
Notes:
------
1. An overhead stirrer is essential - the stirbar will get clogged with MnO2.
2. KMnO4 solubility is 1 in 3.5 parts of hot water and 1 in 14 parts of cold water.
3. The acetone was added to try to clear the sludge. I would have added more but I had second thoughts.
Refs:
1. Synthesis Of Aliphatic And Alicyclic Nitro Compounds; Org. Syn. p 131-132 [The Oxidation of Amines]
2. Organic Syntheses, Vol. 52, pp 77-82, 2-Metryl-2-Nitrosopropane and its Dimer, A. Calder, A. R. Forrester and S. P. Hepburn.
3. Vogel's Practical Organic Chemistry, 4th ed. P 564 'Nitromethane'.
Questions.
----------
1. Is it safe to heat this mixture to 90C without a stirrer? [the next step to make sure that nitro-propionic acid is decarboxylated]
2. Should I improvise an overhead stirrer to finish this off?
3. Nitroethane will steam distil won't it?
4. Should the permanganate have been buffered?
5. I think the NaOH should have been in there from the start. The sodium salt of alanine would have been a better idea?
6a. Would the reaction benefit from taking place in an organic solvent?
6b. If so, what solvents are suitable apart from acetone?
I will repeat this - with an overhead stirrer and the addition of sodium salt of alanine rather than alanine followed by NaOH.

Method 19:  Reduction of acetaldehyde oxime and oxidation of the product

Good work ! An alternative method to alanine amino oxidation and decarboxylation is the reaction : CH3CHO + NH2OH ==>> CH3CH=NOH,
Then carfully reduced to CH3CH2NHOH, and then oxidized as proposed by you above to get CH3CH2NO



Osmium

  • Guest
Rearrangement of ethyl nitrite.

Aurelius

  • Guest
BTW, Rhodium, you can place all those synths as a nitroethane FAQ- it's not quite complete, but with a little help, aurelius can complete it.  mostly, aurelius just lacks access to a few of the articles.  that and everything that's available on the hive and your site for nitroethane is on this so far.  (if aurelius missed something, please tell aurelius so it can be included)


joyman

  • Guest

Method 11:  3-chloropropionic acid sodium salt, and NaNO2

ClCH2CH2COONa + NaNO2 „³ NO2CH2CH2COONa + NaCl

NO2CH2CH2COONa + H2O ¡Vheat„³  NO2CH2CH3 + NaHCO3

Modification of Nitromethane synthesis from Organic Synthesis, Vol? Pg 401.




WizardX mentioned this a couple of times but didn't give the full reference - heres the ref.

From Organic Syntheses, Collective Vol. I, pp 401-403,

To 500 g of chloroacetic acid in 500 g cracked ice add enough 40% NaOH solution to make the resulting mixture slightly alkaline. Do not let the temperature rise above 20 degrees C. This solution is mixed with 365 g sodium nitrite dissolved in 500 ml water in a 3 liter round-bottom flask. This flask should then be equipped with a thermometer dipping into the liquid and a distillation condenser. The mixture is carefully heated until the first bubbles or carbon dioxide appear (at about 80 C). The heat is then withdrawn and the heat of the reaction keeps it warm. If the reaction becomes too vigorous, it should be cooled. After the reaction ceases, heat cautiously until 110 C is reached. Nitromethane will distill over during this heating and the previous spontaneous heating. Separation of the nitromethane / water mixture and redistillation will give approx. 35 % yield after drying and redistillation.


Aurelius

  • Guest
Joyman, your the greatest.  thanks


Marcus

Antoncho

  • Guest
Ethyl nitrite rearrangement doesn't work (at least, for any practical purpose).
If you carefully read the original article you'll see why - the rate of convertion is way too slow .

Antoncho

Aurelius

  • Guest
ok, aurelius is just collecting what's been posted through the years.  would somebody please state whether the ethyl nitrite route is rearrangement, isomerization or whatever.  the article (at least) is correct.  aurelius would like somebody (Antoncho-who has obviously seen the article) to post the article so that the rest can observe and aurelius can perhaps remove that method or include its experimental portions.


Aurelius

  • Guest

some stuff from a while back on the hive

rev drone
It makes sense. Thermodynamically, this is quite favorable. But the only references I can find to the isomerization of lower alkyl nitrites into lower nitoalkanes involve considerable heat and pressure -- not to mention the occasional asbestos catalyst.
So does anybody have any good ideas about any magical transition metal catalysts that could facilitate isomerization at more ambient conditions? It looks so good, so obtainable, yet somehow its so out-of reach.

------------------
-the good reverend drone

Ipsa scientia potestas est


Chem Guy
Not Fe, that's for sure. 
Intutively, I would say Lewis acid catalyzed rearrangement, but that is only a whim.  I don't know for sure. 


Acme
My magic 8-ball came up blank on this one.
I asked it (reactant)GH-CH2-CH2-O-N-O --->> (product)GH-CH2-CH2-NO2 and big fat goose egg was the reply, sadly

Osmium
Share the refs you already have Drone.
I've never heard something like that


rev drone
J.Chem.Soc.; 109; 1916; 701;
------------------
-the good reverend drone

Ipsa scientia potestas est

Aurelius

  • Guest
Here's the updated list:

Nitroethane synthesis: a compilation

Method 1: from sodium ethyl sulfate and a metal nitrite

1.5 mole sodium nitrite (103.5g) is intimately mixed with 1 mole of sodium ethyl sulfate (158g) and 0.0625 moles of K2CO3 (8.6g). The mixture is then heated to 125-130°C, at which temperature the nitroethane distills over as soon as it is formed. The heating is discontinued when the distillation flow slackens considerably, and the crude nitroethane is washed with an equal amount of water, dried over CaCl2, and if needed, decolorized with a little activated carbon. The nitroethane is then re-distilled, collecting the fraction between 114-116°C. Yield 46% of theory

(another ref says max. 42%)
Chemical Abstracts, Vol 49, pg 836.

Method 2: from diethyl sulfate and sodium nitrite

Initial run - Into a stoppered bottle was placed a mixture of diethyl sulfate (120g) and sodium nitrite solution (120g in 160ml of water.) The bottle was shaken mechanically for 20 hours, the pressure being released at intervals. The contents were then poured into a separating funnel, and the upper layer separated, dried over calcium chloride. and distilled at 14 mmHg, the distillate up to 60°C being collected (the residue, ca. 230g., consisted of ethyl sulphate and was used again). The distillate was fractionated at atmospheric pressure, and the fraction of bp 114-116°C collected. This was shaken with water, dried over calcium chloride, run through charcoal, and redistilled; bp 114-115.5°C. Yield, 17.7g. (31%, or allowing for recovered ethyl sulfate, 43.5%).

    Routine run - A second experiment was then carried out using the same quantity of ethyl sulfate as above. The recovered nitrite solution (lower layer) from the first run was concentrated by adding approximately 16 g. of sodium nitrite per 160ml of solution. Yield 26.4g (46%, or allowing for recovered ethyl sulphate, 65%). For each additional subsequent run approximately 16 g. of nitrite per 160 ml of solution were added, although this represents a rather diminishing concentration in view of the increased yield of nitroethane


Method 3: from ethyl bromide (iodide) and sodium nitrite (dmf)
32.5 grams of ethyl bromide (0.3 moles) was poured into a stirred solution of 600ml dimethylformamide and 36 grams dry NaNO2 (0.52 mole) in a beaker standing in a water bath keeping the solution at room temperature as the reaction is slightly exothermic. Always keep the solution out of direct sunlight. The stirring was continued for six hours. After that, the reaction mixture was poured into a 2500 ml beaker or flask, containing 1500 ml ice-water and 100 ml of petroleum ether. The petroleum ether layer was poured off and saved, and the aqueous phase was extracted four more times with 100 ml of petroleum ether each, where after the organic extracts were pooled, and in turn was washed with 4x75ml of water. The remaining organic phase was dried over magnesium sulfate, filtered, and the petroleum ether was removed by distillation under reduced pressure on a water bath, which temperature was allowed to slowly rise to about 65°C. The residue, consisting of crude nitroethane was distilled under ordinary pressure (preferably with a small distillation column) to give 60% of product, boiling at 114-116°C.
 
 The ethyl bromide reacts with NaNO2, forming nitroethane and ethyl nitrite.
This method can be varied in a few ways. Firstly, dimethyl sulfoxide (DMSO) can be substituted for the dimethylformamide (DMF) as solvent. Ethylene glycol also works as solvent, but the reaction proceeds pretty sluggishly in this medium, allowing for side reactions, such as this: RH-NO2 + R-ONO => R-(NO)NO2 + R-OH. KNO2 can also be used instead of NaNO2. If NaNO2 is used in DMF, 30g (0.5 mol) of urea can also be added as nitrite scavenger to minimize side reactions, as well as simultaneously increasing the solubility of the NaNO2 and thereby significantly speeding up the reaction.

           If the ethyl bromide is substituted with ethyl iodide, the required reaction time is decreased to only 2.5 h instead of 6 h. In case ethyl iodide is employed, a slight change in the above procedure needs to be done. The pooled pet ether extracts should be washed with 2x75ml 10% sodium thiosulfate, followed by 2x75ml water, instead of 4x75ml water as above. This to remove small amounts of free iodine

Method 4 : from ethyl halide and silver nitrite

Cool 100 g of silver nitrite (0.65 mol) in 150 ml of dry ether to 0°C in a 3 neck 500 ml flask (in a darkened room or using yellow light). Add 0.5 moles of ethyl halide (78g ethyl iodide or 55g of ethyl bromide) dropwise over a 2 hour period while stirring constantly and maintaining the temperature at 0°C and dark conditions. Stir for 24 hours at 0°C, then 24 hours at room temp if using ethyl bromide, and 48h if using ethyl bromide. (Test for halogens to see when the reaction is completed, through adding a few drops of the reaction mixture to a test tube containing an alcoholic solution of silver nitrate and note if a precipitate appears. If so, the reaction is not complete. The Beilstein test can also be used, it uses a small coil of copper wire in a test tube to which a small portion of the reaction mixture is added and it is noted if reaction occurs, where elemental silver will deposit on the surface of the copper coil.) Silver iodide (or bromide) will precipitate in the solution during the course of the reaction. Filter off the silver salt, and wash it with several portions of ether. Evaporate the ether at room temperature. (This may be substituted with distillation of the ether using a water bath at atmospheric pressure. A 2x45 cm column packed with 4 mm pyrex helices is used. A more efficient column is not used due to the instability of the ethyl nitrite formed as a by-product in the reaction. Maintain anhydrous conditions since the ethyl nitrite will hydrolyze to ethanol and will be difficult to separate.) Then vacuum distill the residue at about 5 mmHg. The ethyl nitrite will be the initial fraction, followed by an intermediate fraction, then the nitroethane will distill. The yield is about 83% of theory


Method 5: oxidation of ethyl amine with peracids  (m-perbenzoicacid)

General Procedure for the Oxidation of Primary & Secondary amines using m-chloroperbenzoic acid.

m-Chloroperbenzoic acid (4.1g, 0.02mol, 85% pure) is dissloved in 30 mls of 1,2-dichloroethane in a three-neck flask equipped with a condenser and a pressure-equalising dropping funnel. The amine (0.005 mol) in 3-5 mls of 1,2-dichloroethane solvent is added drop-wize to the refluxing m-Chloroperbenzoic acid/1,2-dichloroethane solution. Refluxing temperature 83oC for 3 hours.
After the addition of the amine and refluxing time, the reaction mixture is cooled, filtered and washed with three 50 ml portions of 1M sodium hydroxide solution and dried over anhydrous magnesium sulphate. The removal of the 1,2-dichloroethane solvent by distillation (rotary) gives a crude nitroalkane. Purification of the crude crude nitroalkane with vacuum distillation. Yields vary, approx 62 %.

Oxidation of n-propylamine and higher alkane amines give nitroalkane at approx 62 %.

[Note] Nitromethane and nitroethane form sodium water-soluable salts with 1M sodium hydroxide solution

Refs: W.D. Emmons, Am.Soc. 79, 5528 (1957)

Method 6: oxidation of ethyl amine with potassium permanganate
Perhaps by the method in Org Synth CV 5, 845. 

   REFS for methods 5 + 6:


Chem.Ber. (1902) 35, 4294
Eur.J.Med.Chem. (1991) 26, 2, 167-178
Eur.J.Org.Chem. (1998) 4, 679-682
Heterocycles (1998) 48, 1, 181-185
J.Amer.Chem.Soc. (1954) 76, 4494
J.Amer.Chem.Soc. (1956) 78, 4003
J.Amer.Chem.Soc. (1957) 79, 5528
J.Chem.Soc.Chem.Commun. (1995) 15, 1523-1524
J.Org.Chem. (1960) 25, 2114-2126
J.Org.Chem. (1979) 44, 659-661.
J.Org.Chem. (1992) 57, 25, 6759-6764
J.Org.Chem. (1993) 58, 5, 1118-1121
Magn.Reson.Chem. (1997) 35, 2, 131-140
Org.Synth. (1963) 43, 87
Tetrahedron (1991) 47, 28, 5173-5184
Tetrahedron (1995) 51, 41, 11305-11318
Tetrahedron Lett. (1981) 22, 18, 1655-1656
Tetrahedron Lett. (1986) 27, 21, 2335-2336
Tetrahedron Lett. (1996) 37, 6, 805-808
Z.Naturforsch.B (1989) 44, 11, 1475-1478

Method 7:  destructive distillation of alpha-bromopropionic acid with sodium nitrite

   K2CO3 + NaNO2 + H2O + a-br-propionic acid ? nitroethane 50%yield

   Add 20g of the acid to a solution of K2CO3 in the amount of base that causes the solution to be basic to phenolphthalein.  The add 20g of NaNO2—there should be approx. 100ml of solution.  Place in a 250ml rb flask and distill quickly- the first 100ml will come over before the rxn takes place.  Then the nitroethane comes over. Distill until no more product comes over.  (don’t distill to dryness) 

V. Auger. Bull. Soc. Chim. France  Post no. 3, 23, 333 (1900) by the kolbe method.

Method 8:  oxidation of ethyl amine to nitroethane with dimethyldioxirane

    A new synthesis of nitro compounds using dimethyldioxirane(DMDO)
Tetrahedron Letters,Vol.27,No.21,pp 2335-2336,1986

Abstract: Dimethyldioxirane oxidizes primary amines to nitro compounds in a facile, mild, high yield process.

Here we report that aliphatic and aromatic primary amines are rapidly and efficiently oxidized to nitro compounds by dimethyldioxirane, DMDO. Indeed a survey of some general methods for the preparation of nitro compounds (2) suggests to us that the use of DMDO may be the method of choice. The conditions used are exceedingly mild and give the nitro compound as a solution in acetone. Table 1 summarizes our results with some representative amines.

Table 1. Oxidation of amines with Dimethyldioxirane(DMDO).
Amine            Product           Yield    (Product m.p.(C)
~~~~~~~~~~~~~~~~~~~~~~~--~~~~~~--~---~~~~~~~~~~~--
Aniline           Nitrobenzene        91
p-Anisidine       p-Nitroanisole      94            54
n-Butylamine      1-Nitrobutane       84
sec-Butylamine    2-Nitrobutane       81
tert-Butylamine   2-Methyl-2-nitrobut 90
1-Aminoadamantane 1-Nitroadamsntane   95            159
Cyclohexylamine   Nitrocyclohexane    95
trans-Azobenzene  Axoxybenzene        96            36

In a typical reaction n-butylamine (0.052g; 0.7 mmol) in 5 ml of acetone was treated with 95 ml of DMDO, in acetone solution (ca 0.05M)(4) The solution was kept at room temperature for 30 min. with the exclusion of light. Analysis of the reaction mixture by capillary GC indicated the presence of l-nitrobutane only. The oxidations are believed to occur by means of successive oxidations by,1. In the aniline case the blue color of the nitroso conpound is observed immediately upon adding the solution of DMDO. In separate experiments we have shown that both phenylhydroxylamine and nitrosobenzene are readily oxidized to nitrobenzene by DMDO. The blue color of intermediate nitroso compound was observed in all of the amine oxidations.

Dimethyldioxirane is a powerful oxygen atom donor, which oxidizes a variety of substrates 'including hydrocarbons'. Work is continuing on the oxidation of nitrogen-containing compounds by DMDO.

1. Chemistry of Dioxiranes. 5. Paper 4 of this series is J. Am. Chem. Soc., in press (1986).
2. H.O. Larson in The Chemistry of the Nitro and Nitroso Groups, H. Feuer, Ed., J. Wiley and Sons. N.Y. 1969.
4. The concentration of,DMDO in acetone was determined by titrating an aliquot with phenyl methyl sulfide. The synthesis of DMDO has been described (5).
5. R.W. Murray and R. Jeyaraman, J. Org. Chem., (50) 2847 (1985).
Dioxiranes:  synthesis and reactions of methyldioxiranes.
J. Org. Chem.  (1985),  50(16),  2847-53.

Abstract
The peroxymonosulfate-acetone system produces dimethyldioxirane under conditions permitting distn. of the dioxirane from the synthesis vessel.  The same conditions were used to prep. other methyldioxiranes.  Solns. of dimethyldioxirane prepd. in this manner were used to study its chem. and spectroscopic properties.  The caroate-acetone system was also used to study the chem. of in situ generated dimethyldioxirane.  cis- And trans-stilbenes were converted stereospecifically to the corresponding epoxides with dimethyldioxirane in acetone

Other refs: Oxidation of primary amines by dimethyldioxirane:
Murray, R.W.,S.N. Rajadhyaksha, L. Mohan, J. Org. Chem., 1989, 54, 5783


Method 9:  isomerization of ethyl nitrite to nitroethane over asbestos catalyst

   J. Chem. Soc. 109, 701 (1916)
   (pass over asbestos in a tube furnace @ 120-130*C for best results/best yield)

Method 10: ethyl bromide, DMSO, NaNO2 and phloroglucinol dihydrate

   By Ritter, in Strike’s book- TSII.

   32g or 26ml EtBr is poured into 250ml of DMSO with 36g NaNO2 and 52g phloroglucinol already present in solution.  (Pglucinol is expensive but can be recycled) put on good mag. stirring and stopper the flask.  Stir for two hours in emulsion form, then dump into a 600ml of ice water and extract twice with DCM. (2x200ml)   dry the extracts with  MgSO4 or CaCl2 the evap off the DCM.  Distill and collect the fraction from 113-116*C--- yields about 20g of nitroethane (80%)  (another ref say maybe over 90% consistently)

Other notes:  catechol and resorcinol have the same nitrite scavenging abilities as phloroglucinol.  And ethylene glycol can be used as a solvent.  A simple NaOH wash of the final solution (nitroethane removed) will give the sodium salt of your phloroglucinol catalyst.  Acidification of the solution will precip the catalyst for recovery by filtration.

JACS 79, 2507 (1957)
Tetrahedron vol 46, No 21, pp 7443-57 (1990)
Ber. 11, 1332 (1878)
Ber. 12, 417 (1879)
JACS, Vol 78, 1497-1501

Method 11:  3-chloropropionic acid sodium salt, and NaNO2

   ClCH2CH2COONa + NaNO2 ? NO2CH2CH2COONa + NaCl

   NO2CH2CH2COONa + H2O –heat?  NO2CH2CH3 + NaHCO3

From Organic Syntheses, Collective Vol. I, pp 401-403

To 500 g of chloroacetic acid in 500 g cracked ice add enough 40% NaOH solution to make the resulting mixture slightly alkaline. Do not let the temperature rise above 20 degrees C. This solution is mixed with 365 g sodium nitrite dissolved in 500 ml water in a 3 liter round-bottom flask. This flask should then be equipped with a thermometer dipping into the liquid and a distillation condenser. The mixture is carefully heated until the first bubbles or carbon dioxide appear (at about 80 C). The heat is then withdrawn and the heat of the reaction keeps it warm. If the reaction becomes too vigorous, it should be cooled. After the reaction ceases, heat cautiously until 110 C is reached. Nitromethane will distill over during this heating and the previous spontaneous heating. Separation of the nitromethane / water mixture and redistillation will give approx. 35 % yield after drying and redistillation


Method 12:  most complicated synth

   CH3CH=NOH  + Cl2 ? CH3CH (Cl)(NO)   (? gem-chloronitrosoethane)

   Gem-comp + O3 ? CH3CH (Cl)(NO2)

   CH3CH (Cl)(NO2) + NaOH + H2 + Pd/C ? nitroethane (50%) + HCl

JOCS, Vol 41, pg 733-735 (1976)

Method 13:  electrochemical oxidation ---- not possible by method below

   Ethyl amine is oxidized to methyl nitrile in anhydrous solvent.  In the presence of water it is oxidized to the imine, then acetaldehyde which is further oxidized to acetic acid.

Method 14:  Vapor Phase nitration of propane.

   The propane is bubbled through nitric acid heated to 108*C and lead into a reactor at 420*C.  the product is then condensed and fractionated.  (26% nitroethane formed)

Industrial and Engineering Chemistry, Vol 28, Mar, 1936. Pg 339-344.
JOC, Vol 17, pg 906-944.

Method 15:  Vapor Phase nitration of ethane.

Same as propane but at least 80% yields. 

Industrial and Engineering Chemistry, Vol 28, Mar, 1936. Pg 339-344.
JOC, Vol 17, pg 906-944.

Method 16:  Vapor Phase Nitration of Ethanol using Group II oxides or halides as a catalyst (works for methanol and propanol too)

US pat # 4431842

Method 17: Distillation of alpha-bromopropionic acids with NaNO2 in the presence of Magnesium Sulfate in DMSO

US pat # 4319059

(the alpha-bromo acid can be obtained using propionic acid in the procedure from Org. Synth. CV 1, 115.)

This patent shows an easy route from alpha-bromopropionic acid to nitroethane in excellent yield. The patent also say that Magnesium chloride, bromide or sulfate may be used instead of the magnesium methoxide, but it doesn't say if this affects yields.

The reaction proceeds as follows: In the polar aprotic solvent DMSO, the alpha-bromopropionic acid reacts in an SN2 fashion with nitrite ion to give alpha-nitropropionic acid and bromide ion. The role of the Mg2+ ion in the reaction is to facilitate the decarboxylation (removal of CO2) from the intermediate nitro acid, as it forms a chelate between one of the oxygen atoms on the nitro group and the oxygen anion of the carboxylic acid. The electron-withdrawing nature of the nitro group makes the carboxylic acid group labile, and it can easily be given off as carbon dioxide. If magnesium methoxide is used in place of the other magnesium salts, the carboxylic acid is directly deprotonated, probably making the reaction go even faster.

There is no workup mentioned in the patent, but I'd suggest flooding with water (or using large amounts of dilute (5%) HCl in the hydrolysis step), and then extract the nitroethane with dichloromethane, ether or possibly petroleum ether. Then the combined organic layers are washed first with water and then with a concentrated NaCl solution, followed by drying the organic phase over anhydrous MgSO4, which is then filtered off. Then the solvent is removed distilled, and the residual crude nitroethane is fractionally distilled at 114-115°C.

alpha-Bromopropionic acid can be made from propionic acid and phosphorous tribromide (from red phosphorous and bromine, the Hell-Volhard-Zelinsky reaction,

http://www.geocities.com/chempen_software/reactions/RXN099.htm

or

http://www.orgsyn.org/orgsyn/default.asp?formgroup=base_form_group&dbname=orgsyn

), or by HBr bromination of lactic acid (alpha-hydroxypropionic acid).

Example 1

To a mixture of magnesium methoxide (0.11 mole) and dimethyl sulfoxide (50 ml) a-bromopropionic acid (0.11 mole) was added at 20°C. with stirring. To this mixture a solution of sodium nitrite (0.145 mole) in dimethyl sulfoxide (65 ml) was added at room temperature. Then, the reaction mixture was stirred at room temperature for 6 hours and was neutralized upon addition of diluted hydrochloric acid. Analysis of the reaction mixture indicated more than 99% conversion of alpha-bromopropionic acid and 94.5% yield of nitroethane.

Example 2

In the manner of Example 1, sodium nitrite, alpha-bromopropionic acid and magnesium methoxide were reacted in dimethyl sulfoxide as the aprotic solvent. The reaction time was 2 hours for one run and 22 hours for another. Reaction was conducted at room temperature. The run at 2 hours converted only 94.5% of the acid and yielded 72.7% nitroethane. The second run at 22 hours gave a conversion of > 99% and a yield of 100%.

At room temperature the reaction apparently takes about 4-5 hours to go to completion. At higher temperatures of 40°C. up to about 75°C. the reaction time is shorter. Thus, one or two hours or even less time at 75°C. will completely convert the bromoacid to the intermediate which can then be decomposed to the nitroalkane.

When using dimethyl sulfoxide as solvent temperatures approaching 100°C should be avoided since the solvent will volatilize and decompose at about 100°C. Other aprotic solvents may not have this disadvantage


Method 18:  Oxidation of alanine with permanganate followed by decarboxylation

Nitroethane via oxidation of alanine? 
 
 Theory
------
MeCH(NH2).COOH + 3(O) --> MeCH(NO2).COOH + H2O.
MeCH(NO2).COOH + NaOH --> MeCH(NO2).COONa.
MeCH(NO2).COONa + H2O --> MeCH2(NO2) + NaHCO3.
Procedure
---------
A solution of potassium permanganate (0.3 mol) in water was made by dissolving 47.41 g KMnO4 in 400 mL hot water in a 1 L 3-necked flask fitted with a reflux condenser, a stirbar[note 1], thermometer, and a 100-mL addition funnel. As the solution cools to room temperature fine crystals of KMnO4 crystallise out of solution[note 2]. A solution of alanine (0.1 mol, 8.91 g) in 65 mL of water was placed in the addition funnel and added dropwise with stirring over a 20 minute period. The temperature slowly rose. When the addition was complete, the reaction mixture was heated to 60º over a period of approximately 2 hours. 40 mL of acetone was added [note 3] and then the reaction mixture maintained at 70-85º [the sludge was extremely viscous and the stirbar was of no use] for 2 hours. 0.1 mol sodium hydroxide in 20 mL of water was then added through the addition funnel.
Pause (to be completed).
-----
The flask showed no sign of heating up after addition of the NaOH. By now the black/brown sludge will not mix (with the stir-bar). The next step is to heat to 80-100C to decarboxylate any nitro-propionic acid and then to steam distil.
Notes:
------
1. An overhead stirrer is essential - the stirbar will get clogged with MnO2.
2. KMnO4 solubility is 1 in 3.5 parts of hot water and 1 in 14 parts of cold water.
3. The acetone was added to try to clear the sludge. I would have added more but I had second thoughts.
Refs:
1. Synthesis Of Aliphatic And Alicyclic Nitro Compounds; Org. Syn. p 131-132 [The Oxidation of Amines]
2. Organic Syntheses, Vol. 52, pp 77-82, 2-Metryl-2-Nitrosopropane and its Dimer, A. Calder, A. R. Forrester and S. P. Hepburn.
3. Vogel's Practical Organic Chemistry, 4th ed. P 564 'Nitromethane'.
Questions.
----------
1. Is it safe to heat this mixture to 90C without a stirrer? [the next step to make sure that nitro-propionic acid is decarboxylated]
2. Should I improvise an overhead stirrer to finish this off?
3. Nitroethane will steam distil won't it?
4. Should the permanganate have been buffered?
5. I think the NaOH should have been in there from the start. The sodium salt of alanine would have been a better idea?
6a. Would the reaction benefit from taking place in an organic solvent?
6b. If so, what solvents are suitable apart from acetone?
I will repeat this - with an overhead stirrer and the addition of sodium salt of alanine rather than alanine followed by NaOH.

Method 19:  Reduction of acetaldehyde oxime and oxidation of the product

Good work ! An alternative method to alanine amino oxidation and decarboxylation is the reaction : CH3CHO + NH2OH ==>> CH3CH=NOH,
Then carfully reduced to CH3CH2NHOH, and then oxidized as proposed by you above to get CH3CH2NO

nitroethane from acetaldoxime
J.H. Boyer / H. Alul, Am.Soc. 81, 4237 (1959)

Method 20: Oxidation of ethyl amine with CrO3

Somewhere in Vogel’s (the oxidation)

Method 21:  Nitroethane from propyl nitrate

J.B. Levy / F.J. Adrian, Am.Soc. 77, 2015 (1954)

Method 22:   Nitroethane from nitroethene (and nitroethanol)

Nitromethane and formaldehyde will produce nitroethene in vapor phase, over silica-supported lead catalysts at 200o.  You can always use Baker's yeast. Nitroalkene in Pet. Ether with bakers yeast for a couple days will reduce it to the nitroalkane.

CH3NO2 + HCOH == NaOH ==>> HOCH2CH2NO2 Aldol Condensation.

HOCH2CH2NO2 == heat ==>> H2C=CH-NO2 + H2O

nitromethane and formaldehyde are reacted in alkaline solution, they give nitroethanol; this can bee dehydrated to nitroethene by concentrated acid, or again in vapor phase, passing over phosphoric acid or boric anhydride. Suppose one wanted to use such means to convert nitromethane, which is easy to get, to nitroethane, which is not. A selective reduction of the double bond, in the presence of the nitro group, would do the trick

As an alternative: in general, aldehydes and ketones will also react in the presence of alumina and KF ( at r.t.) to form beta-nitroalcohols, which typically dehydrate to nitroalkenes in very acidic conditions. See Tetrahedron Letters, Vol 27, 1986, p493. This article doesn't specifically use nitroethene as an example, but the other compounds tested (which are larger) gave yields of nitroalcohol around 70%. The conversion to the nitroalkene *should* be stoichiometric. I expect this method may also yield nitrostyrenes with a similar degree of success




Antoncho

  • Guest
i think Megamole has an interesting article on peracetic acid oxid'n of alkylamines...

Anyone wishes to ask him for it? ;D  ;D

Antoncho

Aurelius

  • Guest
newest method
« Reply #29 on: September 11, 2002, 10:09:00 PM »
here's what available on the hive, thus far:

Nitroethane synthesis: a compilation

Method 1: from sodium ethyl sulfate and a metal nitrite

1.5 mole sodium nitrite (103.5g) is intimately mixed with 1 mole of sodium ethyl sulfate (158g) and 0.0625 moles of K2CO3 (8.6g). The mixture is then heated to 125-130°C, at which temperature the nitroethane distills over as soon as it is formed. The heating is discontinued when the distillation flow slackens considerably, and the crude nitroethane is washed with an equal amount of water, dried over CaCl2, and if needed, decolorized with a little activated carbon. The nitroethane is then re-distilled, collecting the fraction between 114-116°C. Yield 46% of theory

(another ref says max. 42%)
Chemical Abstracts, Vol 49, pg 836.

Method 2: from diethyl sulfate and sodium nitrite

Initial run - Into a stoppered bottle was placed a mixture of diethyl sulfate (120g) and sodium nitrite solution (120g in 160ml of water.) The bottle was shaken mechanically for 20 hours, the pressure being released at intervals. The contents were then poured into a separating funnel, and the upper layer separated, dried over calcium chloride. and distilled at 14 mmHg, the distillate up to 60°C being collected (the residue, ca. 230g., consisted of ethyl sulphate and was used again). The distillate was fractionated at atmospheric pressure, and the fraction of bp 114-116°C collected. This was shaken with water, dried over calcium chloride, run through charcoal, and redistilled; bp 114-115.5°C. Yield, 17.7g. (31%, or allowing for recovered ethyl sulfate, 43.5%).

Routine run - A second experiment was then carried out using the same quantity of ethyl sulfate as above. The recovered nitrite solution (lower layer) from the first run was concentrated by adding approximately 16 g. of sodium nitrite per 160ml of solution. Yield 26.4g (46%, or allowing for recovered ethyl sulphate, 65%). For each additional subsequent run approximately 16 g. of nitrite per 160 ml of solution were added, although this represents a rather diminishing concentration in view of the increased yield of nitroethane


Method 3: from ethyl bromide (iodide) and sodium nitrite (dmf)
32.5 grams of ethyl bromide (0.3 moles) was poured into a stirred solution of 600ml dimethylformamide and 36 grams dry NaNO2 (0.52 mole) in a beaker standing in a water bath keeping the solution at room temperature as the reaction is slightly exothermic. Always keep the solution out of direct sunlight. The stirring was continued for six hours. After that, the reaction mixture was poured into a 2500 ml beaker or flask, containing 1500 ml ice-water and 100 ml of petroleum ether. The petroleum ether layer was poured off and saved, and the aqueous phase was extracted four more times with 100 ml of petroleum ether each, where after the organic extracts were pooled, and in turn was washed with 4x75ml of water. The remaining organic phase was dried over magnesium sulfate, filtered, and the petroleum ether was removed by distillation under reduced pressure on a water bath, which temperature was allowed to slowly rise to about 65°C. The residue, consisting of crude nitroethane was distilled under ordinary pressure (preferably with a small distillation column) to give 60% of product, boiling at 114-116°C.

The ethyl bromide reacts with NaNO2, forming nitroethane and ethyl nitrite.
This method can be varied in a few ways. Firstly, dimethyl sulfoxide (DMSO) can be substituted for the dimethylformamide (DMF) as solvent. Ethylene glycol also works as solvent, but the reaction proceeds pretty sluggishly in this medium, allowing for side reactions, such as this: RH-NO2 + R-ONO => R-(NO)NO2 + R-OH. KNO2 can also be used instead of NaNO2. If NaNO2 is used in DMF, 30g (0.5 mol) of urea can also be added as nitrite scavenger to minimize side reactions, as well as simultaneously increasing the solubility of the NaNO2 and thereby significantly speeding up the reaction.

           If the ethyl bromide is substituted with ethyl iodide, the required reaction time is decreased to only 2.5 h instead of 6 h. In case ethyl iodide is employed, a slight change in the above procedure needs to be done. The pooled pet ether extracts should be washed with 2x75ml 10% sodium thiosulfate, followed by 2x75ml water, instead of 4x75ml water as above. This to remove small amounts of free iodine

Method 4 : from ethyl halide and silver nitrite

Cool 100 g of silver nitrite (0.65 mol) in 150 ml of dry ether to 0°C in a 3 neck 500 ml flask (in a darkened room or using yellow light). Add 0.5 moles of ethyl halide (78g ethyl iodide or 55g of ethyl bromide) dropwise over a 2 hour period while stirring constantly and maintaining the temperature at 0°C and dark conditions. Stir for 24 hours at 0°C, then 24 hours at room temp if using ethyl bromide, and 48h if using ethyl bromide. (Test for halogens to see when the reaction is completed, through adding a few drops of the reaction mixture to a test tube containing an alcoholic solution of silver nitrate and note if a precipitate appears. If so, the reaction is not complete. The Beilstein test can also be used, it uses a small coil of copper wire in a test tube to which a small portion of the reaction mixture is added and it is noted if reaction occurs, where elemental silver will deposit on the surface of the copper coil.) Silver iodide (or bromide) will precipitate in the solution during the course of the reaction. Filter off the silver salt, and wash it with several portions of ether. Evaporate the ether at room temperature. (This may be substituted with distillation of the ether using a water bath at atmospheric pressure. A 2x45 cm column packed with 4 mm pyrex helices is used. A more efficient column is not used due to the instability of the ethyl nitrite formed as a by-product in the reaction. Maintain anhydrous conditions since the ethyl nitrite will hydrolyze to ethanol and will be difficult to separate.) Then vacuum distill the residue at about 5 mmHg. The ethyl nitrite will be the initial fraction, followed by an intermediate fraction, then the nitroethane will distill. The yield is about 83% of theory


Method 5: oxidation of ethyl amine with peracids  (m-perbenzoicacid)

General Procedure for the Oxidation of Primary & Secondary amines using m-chloroperbenzoic acid.

m-Chloroperbenzoic acid (4.1g, 0.02mol, 85% pure) is dissloved in 30 mls of 1,2-dichloroethane in a three-neck flask equipped with a condenser and a pressure-equalising dropping funnel. The amine (0.005 mol) in 3-5 mls of 1,2-dichloroethane solvent is added drop-wize to the refluxing m-Chloroperbenzoic acid/1,2-dichloroethane solution. Refluxing temperature 83oC for 3 hours.
After the addition of the amine and refluxing time, the reaction mixture is cooled, filtered and washed with three 50 ml portions of 1M sodium hydroxide solution and dried over anhydrous magnesium sulphate. The removal of the 1,2-dichloroethane solvent by distillation (rotary) gives a crude nitroalkane. Purification of the crude crude nitroalkane with vacuum distillation. Yields vary, approx 62 %.

Oxidation of n-propylamine and higher alkane amines give nitroalkane at approx 62 %.

[Note] Nitromethane and nitroethane form sodium water-soluable salts with 1M sodium hydroxide solution

Method 6: oxidation of ethyl amine with potassium permanganate
Perhaps by the method in Org Synth CV 5, 845. 

REFS for methods 5 + 6:


Chem.Ber. (1902) 35, 4294
Eur.J.Med.Chem. (1991) 26, 2, 167-178
Eur.J.Org.Chem. (1998) 4, 679-682
Heterocycles (1998) 48, 1, 181-185
J.Amer.Chem.Soc. (1954) 76, 4494
J.Amer.Chem.Soc. (1956) 78, 4003
J.Amer.Chem.Soc. (1957) 79, 5528
J.Chem.Soc.Chem.Commun. (1995) 15, 1523-1524
J.Org.Chem. (1960) 25, 2114-2126
J.Org.Chem. (1979) 44, 659-661.
J.Org.Chem. (1992) 57, 25, 6759-6764
J.Org.Chem. (1993) 58, 5, 1118-1121
Magn.Reson.Chem. (1997) 35, 2, 131-140
Org.Synth. (1963) 43, 87
Tetrahedron (1991) 47, 28, 5173-5184
Tetrahedron (1995) 51, 41, 11305-11318
Tetrahedron Lett. (1981) 22, 18, 1655-1656
Tetrahedron Lett. (1986) 27, 21, 2335-2336
Tetrahedron Lett. (1996) 37, 6, 805-808
Z.Naturforsch.B (1989) 44, 11, 1475-1478

Method 7:  destructive distillation of alpha-bromopropionic acid with sodium nitrite

K2CO3 + NaNO2 + H2O + a-br-propionic acid ? nitroethane 50%yield

Add 20g of the acid to a solution of K2CO3 in the amount of base that causes the solution to be basic to phenolphthalein.  The add 20g of NaNO2—there should be approx. 100ml of solution.  Place in a 250ml rb flask and distill quickly- the first 100ml will come over before the rxn takes place.  Then the nitroethane comes over. Distill until no more product comes over.  (don’t distill to dryness) 

V. Auger. Bull. Soc. Chim. France  Post no. 3, 23, 333 (1900) by the kolbe method.

Method 8:  oxidation of ethyl amine to nitroethane with dimethyldioxirane

A new synthesis of nitro compounds using dimethyldioxirane(DMDO)
Tetrahedron Letters,Vol.27,No.21,pp 2335-2336,1986

Abstract: Dimethyldioxirane oxidizes primary amines to nitro compounds in a facile, mild, high yield process.

Here we report that aliphatic and aromatic primary amines are rapidly and efficiently oxidized to nitro compounds by dimethyldioxirane, DMDO. Indeed a survey of some general methods for the preparation of nitro compounds (2) suggests to us that the use of DMDO may be the method of choice. The conditions used are exceedingly mild and give the nitro compound as a solution in acetone. Table 1 summarizes our results with some representative amines.

Table 1. Oxidation of amines with Dimethyldioxirane(DMDO).
Amine            Product           Yield    (Product m.p.(C)
~~~~~~~~~~~~~~~~~~~~~~~--~~~~~~--~---~~~~~~~~~~~--
Aniline           Nitrobenzene        91
p-Anisidine       p-Nitroanisole      94            54
n-Butylamine      1-Nitrobutane       84
sec-Butylamine    2-Nitrobutane       81
tert-Butylamine   2-Methyl-2-nitrobut 90
1-Aminoadamantane 1-Nitroadamsntane   95            159
Cyclohexylamine   Nitrocyclohexane    95
trans-Azobenzene  Axoxybenzene        96            36

In a typical reaction n-butylamine (0.052g; 0.7 mmol) in 5 ml of acetone was treated with 95 ml of DMDO, in acetone solution (ca 0.05M)(4) The solution was kept at room temperature for 30 min. with the exclusion of light. Analysis of the reaction mixture by capillary GC indicated the presence of l-nitrobutane only. The oxidations are believed to occur by means of successive oxidations by,1. In the aniline case the blue color of the nitroso conpound is observed immediately upon adding the solution of DMDO. In separate experiments we have shown that both phenylhydroxylamine and nitrosobenzene are readily oxidized to nitrobenzene by DMDO. The blue color of intermediate nitroso compound was observed in all of the amine oxidations.

Dimethyldioxirane is a powerful oxygen atom donor, which oxidizes a variety of substrates 'including hydrocarbons'. Work is continuing on the oxidation of nitrogen-containing compounds by DMDO.

1. Chemistry of Dioxiranes. 5. Paper 4 of this series is J. Am. Chem. Soc., in press (1986).
2. H.O. Larson in The Chemistry of the Nitro and Nitroso Groups, H. Feuer, Ed., J. Wiley and Sons. N.Y. 1969.
4. The concentration of,DMDO in acetone was determined by titrating an aliquot with phenyl methyl sulfide. The synthesis of DMDO has been described (5).
5. R.W. Murray and R. Jeyaraman, J. Org. Chem., (50) 2847 (1985).
Dioxiranes:  synthesis and reactions of methyldioxiranes.
J. Org. Chem.  (1985),  50(16),  2847-53.

Abstract
The peroxymonosulfate-acetone system produces dimethyldioxirane under conditions permitting distn. of the dioxirane from the synthesis vessel.  The same conditions were used to prep. other methyldioxiranes.  Solns. of dimethyldioxirane prepd. in this manner were used to study its chem. and spectroscopic properties.  The caroate-acetone system was also used to study the chem. of in situ generated dimethyldioxirane.  cis- And trans-stilbenes were converted stereospecifically to the corresponding epoxides with dimethyldioxirane in acetone

Method 9:  isomerization of ethyl nitrite to nitroethane over asbestos catalyst

J. Chem. Soc. 109, 701 (1916)
(pass over asbestos in a tube furnace @ 120-130*C for best results/best yield)

Method 10: ethyl bromide, DMSO, NaNO2 and phloroglucinol dihydrate

By Ritter, in Strike’s book- TSII.

32g or 26ml EtBr is poured into 250ml of DMSO with 36g NaNO2 and 52g phloroglucinol already present in solution.  (Pglucinol is expensive but can be recycled) put on good mag. stirring and stopper the flask.  Stir for two hours in emulsion form, then dump into a 600ml of ice water and extract twice with DCM. (2x200ml)   dry the extracts with  MgSO4 or CaCl2 the evap off the DCM.  Distill and collect the fraction from 113-116*C--- yields about 20g of nitroethane (80%)  (another ref say maybe over 90% consistently)

Other notes:  catechol and resorcinol have the same nitrite scavenging abilities as phloroglucinol.  And ethylene glycol can be used as a solvent.  A simple NaOH wash of the final solution (nitroethane removed) will give the sodium salt of your phloroglucinol catalyst.  Acidification of the solution will precip the catalyst for recovery by filtration.

JACS 79, 2507 (1957)
Tetrahedron vol 46, No 21, pp 7443-57 (1990)
Ber. 11, 1332 (1878)
Ber. 12, 417 (1879)
JACS, Vol 78, 1497-1501

Method 11:  3-chloropropionic acid sodium salt, and NaNO2

ClCH2CH2COONa + NaNO2 ? NO2CH2CH2COONa + NaCl

NO2CH2CH2COONa + H2O –heat?  NO2CH2CH3 + NaHCO3

Modification of Nitromethane synthesis from Organic Synthesis, Vol? Pg 401.

Method 12:  most complicated synth

CH3CH=NOH  + Cl2 ? CH3CH (Cl)(NO)   (? gem-chloronitrosoethane)

Gem-comp + O3 ? CH3CH (Cl)(NO2)

CH3CH (Cl)(NO2) + NaOH + H2 + Pd/C ? nitroethane (50%) + HCl

JOCS, Vol 41, pg 733-735 (1976)

Method 13:  electrochemical oxidation ---- not possible by method below

Ethyl amine is oxidized to methyl nitrile in anhydrous solvent.  In the presence of water it is oxidized to the imine, then acetaldehyde which is further oxidized to acetic acid.

Method 14:  Vapor Phase nitration of propane.

The propane is bubbled through nitric acid heated to 108*C and lead into a reactor at 420*C.  the product is then condensed and fractionated.  (26% nitroethane formed)

Industrial and Engineering Chemistry, Vol 28, Mar, 1936. Pg 339-344.
JOC, Vol 17, pg 906-944.

Method 15:  Vapor Phase nitration of ethane.

Same as propane but at least 80% yields. 

Industrial and Engineering Chemistry, Vol 28, Mar, 1936. Pg 339-344.
JOC, Vol 17, pg 906-944.

Method 16:  Vapor Phase Nitration of Ethanol using Group II oxides or halides as a catalyst (works for methanol and propanol too)

US pat # 4431842

Method 17: Distillation of alpha-bromopropionic acids with NaNO2 in the presence of Magnesium Sulfate in DMSO

US pat # 4319059

(the alpha-bromo acid can be obtained using propionic acid in the procedure from Org. Synth. CV 1, 115.)


Method 18:  Oxidation of alanine with permanganate followed by decarboxylation

Nitroethane via oxidation of alanine? 

Theory
------
MeCH(NH2).COOH + 3(O) --> MeCH(NO2).COOH + H2O.
MeCH(NO2).COOH + NaOH --> MeCH(NO2).COONa.
MeCH(NO2).COONa + H2O --> MeCH2(NO2) + NaHCO3.
Procedure
---------
A solution of potassium permanganate (0.3 mol) in water was made by dissolving 47.41 g KMnO4 in 400 mL hot water in a 1 L 3-necked flask fitted with a reflux condenser, a stirbar[note 1], thermometer, and a 100-mL addition funnel. As the solution cools to room temperature fine crystals of KMnO4 crystallise out of solution[note 2]. A solution of alanine (0.1 mol, 8.91 g) in 65 mL of water was placed in the addition funnel and added dropwise with stirring over a 20 minute period. The temperature slowly rose. When the addition was complete, the reaction mixture was heated to 60º over a period of approximately 2 hours. 40 mL of acetone was added [note 3] and then the reaction mixture maintained at 70-85º [the sludge was extremely viscous and the stirbar was of no use] for 2 hours. 0.1 mol sodium hydroxide in 20 mL of water was then added through the addition funnel.
Pause (to be completed).
-----
The flask showed no sign of heating up after addition of the NaOH. By now the black/brown sludge will not mix (with the stir-bar). The next step is to heat to 80-100C to decarboxylate any nitro-propionic acid and then to steam distil.
Notes:
------
1. An overhead stirrer is essential - the stirbar will get clogged with MnO2.
2. KMnO4 solubility is 1 in 3.5 parts of hot water and 1 in 14 parts of cold water.
3. The acetone was added to try to clear the sludge. I would have added more but I had second thoughts.
Refs:
1. Synthesis Of Aliphatic And Alicyclic Nitro Compounds; Org. Syn. p 131-132 [The Oxidation of Amines]
2. Organic Syntheses, Vol. 52, pp 77-82, 2-Metryl-2-Nitrosopropane and its Dimer, A. Calder, A. R. Forrester and S. P. Hepburn.
3. Vogel's Practical Organic Chemistry, 4th ed. P 564 'Nitromethane'.
Questions.
----------
1. Is it safe to heat this mixture to 90C without a stirrer? [the next step to make sure that nitro-propionic acid is decarboxylated]
2. Should I improvise an overhead stirrer to finish this off?
3. Nitroethane will steam distil won't it?
4. Should the permanganate have been buffered?
5. I think the NaOH should have been in there from the start. The sodium salt of alanine would have been a better idea?
6a. Would the reaction benefit from taking place in an organic solvent?
6b. If so, what solvents are suitable apart from acetone?
I will repeat this - with an overhead stirrer and the addition of sodium salt of alanine rather than alanine followed by NaOH.

Method 19:  Reduction of acetaldehyde oxime and oxidation of the product

Good work ! An alternative method to alanine amino oxidation and decarboxylation is the reaction : CH3CHO + NH2OH ==>> CH3CH=NOH,
Then carfully reduced to CH3CH2NHOH, and then oxidized as proposed by you above to get CH3CH2NO

NEWEST METHOD---
Method 20: reduction of nitroethene to nitroethane using 2-phenylbenzimidazoline

https://www.thevespiary.org/rhodium/Rhodium/chemistry/phenylbenzimidazoline.html



just thought aurelius would add it to the compilation for posterity and preservation

Bwiti

  • Guest
"A post showed up a few months ago here on the ...
« Reply #30 on: September 12, 2002, 05:00:00 AM »
"A post showed up a few months ago here on the boards describing the failure of NaNO2 and ethyl bromide in a polar aprotic solvent (DMF,DMSO and n-Methylpyrolidinone) to form nitroethane."

  A complete failure? Come on, please tell me you're joking! 

Love my country, fear my government.

SpicyBrown

  • Guest
Was a nitrite scavenger present?
« Reply #31 on: September 12, 2002, 10:20:00 AM »

"A post showed up a few months ago here on the boards describing the failure of NaNO2 and ethyl bromide in a polar aprotic solvent (DMF,DMSO and n-Methylpyrolidinone) to form nitroethane."

  A complete failure? Come on, please tell me you're joking! 




SWIM wonders, was a catechol-type nitrite scavenger used? Quite some time ago, a FOAF or what-not had a failure with EtBr/NaNO2 in DMSO, but not only was the DMSO shit-grade, no nitrite scavenger was used. The FOAF indicates soon the dream will be thought about again in either n,n-DMF or redistilled DMSO with catechol present. Any idea if propylene glycol will work as a solvent?

SpicyBrown


Bwiti

  • Guest
I assumed that since it was on Rhodium's page, ...
« Reply #32 on: September 13, 2002, 03:51:00 AM »
I assumed that since it was on Rhodium's page, then it would work without phlorogluc-whatever - Can't find a source for it that I'm comfortable buying from. I just can't see how one person can fail, then another can get a 60% yield? Is someone full of shit, or did someone fail because they accidentally urinated in the rxn while they were drunk? I don't think that the use of DMSO in place of dimethylformamide would be a problem, but I'm not a chemist. Fuck it, when I get the chems, I'll try it out and post it. What else do I have to lose besides throwing money out the window. :)

Love my country, fear my government.

starlight

  • Guest
Do methods 7 or 11 really work?
« Reply #33 on: October 29, 2002, 07:12:00 PM »
Methods 7 and 11 look very similar in that the salt of a halogenated propionic acid is destructively distilled with Sodium Nitrite.

In method 7 the alpha-halogenated acid is used. In method 11 the beta-halogenated acid is used.

Does anyone know if either of these reactions actually works?

Or do both work? - i.e. does it matter if you have a 2- or 3- halogenated propionic acid?

These reactions appear to be more volumetrically efficient than some of the others from readily easily sourced chemicals, so it would be good to know if anyone has actually had any success with either of these or if they are theoretical at this point.

RedMonn_16

  • Guest
Well, I just LOVE to TEACH !!!
« Reply #34 on: November 05, 2002, 12:45:00 AM »

sponsan

  • Guest
nitroethane is readilly available OTC in the USA
« Reply #35 on: November 08, 2002, 12:25:00 AM »
This is a little bit off topic, but i found three otc sources of nitroethane online in 98%+ concentrations (one was ~8% though).  This stuff is very widely used in many industries, if you know what to search for, you will find it.

The only problem with aquisition is that it is a hazardous class 3 chemical and shipping overseas costs a bomb.  It makes it unrealistic to ship inter-continentally.  But, if you live in the USA, it seems you can just walk into all of these suppliers and buy it.

But for Oz bees, i think the only option is to perform the synth, which is pretty much OTC as well as all the precusrsors are available from a local photo-chem supplier.

TrickEMethod

  • Guest
I would be quite excited if what you were saying ...
« Reply #36 on: November 09, 2002, 11:38:00 AM »
I would be quite excited if what you were saying proved to be the case, but I expect that you are somehow mistaken.  NitroEthane is a listed and more over a high priority item on their 24x7 radar screen.  You woun't find it in some wood restoration kit or as the solvent for some hign end brand of paint.

I think you might be confusing Nitroethane with something else, like maybe nitromethane.  Check the CAS numbers on the msds, that often resolves seemingly too good to be true finds.

If your right I appologize, and I hope I'm not being too much of a doubter, but I definitely doubt it.

It also might have been either a setup or a ripoff.  Both are more likely than a OTC product locatable via a web search, containing a 98% concentration of a primary methamphetamine precursor.

And on the eight day, God created Meth...
... and hasn't done much of anything usefull since!

sponsan

  • Guest
take a look at this product info snippet...
« Reply #37 on: November 10, 2002, 10:35:00 PM »
Could someone please confim if they have managed to successfully aquire the following product (i am sure you'll recognise the format of the doc):




If so, could you please drop me a PM - i'd love to know how you went.

Many Thanks!

El_Zorro

  • Guest
So is that product available on the shelf ...
« Reply #38 on: November 11, 2002, 12:04:00 AM »
So is that product available on the shelf somewhere?  It looks good to me, but if it has to be ordered, I don't think it'd be worth the risk.  But if it can be found on the shelf somewhere near me, I might just have to nut myself.

Who is that masked man?

RedMonn_16

  • Guest
On the Shelf Somewhere.
« Reply #39 on: November 11, 2002, 08:36:00 AM »
I'm sure it's on the shelf somewhere, but I also think that iMac's have this little Cut, Paste, & Post on the Internet feature somewhere on the shelf as well.  Maybe we should ask Libby?  Alternatively, when she lies about it, we could always burn her at the stake again I guess.

"If it's not love, then it's THE BOMB, the bomb, the bomb that will bring us together."--Stephen Morrissey

"Like some liars at a witch trial, ya'll look good for your age."--Courtney Love

sponsan

  • Guest
I shouldn't have used the word "OTC" - sorry my ...
« Reply #40 on: November 12, 2002, 02:03:00 AM »
I shouldn't have used the word "OTC" - sorry my mistake.  What i should have said is "The product was found to be available outside of chemical supply houses".

scram

  • Guest
Someone else mentioned a nitro-ethane reduction ...
« Reply #41 on: November 14, 2002, 09:17:00 PM »
Someone else mentioned a nitro-ethane reduction insitu of nitro-methane here once. I still have my doubts  that guy actually got the shit from his otc drag strip. I live near a major city and I scoured every hobby shop and drag race strip with the area and NONE even had nitromethane. Thanks to Bin Laden, the FBI was even asking local shops about anyone buying model rocket engines after that. Dont ask?! The only place I was able to find ethane was through industrial supply that have chem companies behind them with huge 3 letter names. I wasn't about to venture even trying to build an account with even their smaller distributer and pop off a liter of nitroethane as one of their "free samples." Sponsan if you can pm me and clue me in on how your pulling this off I can do some tricks for you too.

Aurelius

  • Guest
Rhodium
« Reply #42 on: November 22, 2002, 11:47:00 AM »
Hey Rhodium, just noticed that your page (and apparently this thread) lacks mention of US4319059.  please include it on the FAQ at your site.  thanks (if you need aurelius to type out the patent, yet aurelius know)


Rhodium

  • Guest
US Patent 4,319,059
« Reply #43 on: November 22, 2002, 01:44:00 PM »
I have it on my hard drive, but I didn't think it was useful to upload it there before I had collected a few methods on making 2-bromopropionic acid to go with it... I'm too much of a perfectionist.

SUMMARY OF THE INVENTION

An .alpha.-bromoalkanoic acid, e.g., .alpha.-bromopropionic acid, is reacted with an alkali metal nitrite, e.g., NaNO2 in the presence of Mg2+ ion provided by adding a magnesium salt, e.g., MgSO4, to the mixture, all in a solution of an aprotic solvent, e.g., dimethyl sulfoxide. This mixture is allowed to react with stirring at room temperature and then neutralized with a mineral acid, e.g., HCl. The product is a nitroalkane, which in the case of starting with .alpha.-bromopropionic acid is nitroethane.

DETAILED DESCRIPTION OF THE INVENTION

Without attempting to describe the mechanism, the following equation shows the reaction: ##STR1## wherein M is an alkali metal R is H or an alkyl group of 1-4 carbon atoms and the solvent is aprotic. After reacting the mixture it is neutralized with a mineral acid.

Thus, an .alpha.-bromoalkanoic acid reacted with an alkali metal nitrite in the presence of Mg.sup.++ ion in an aprotic solvent will yield a nitroalkane having one less carbon atom than the starting bromo-alkanoic acid. The alkali metal is converted to the salt of the mineral acid used to neutralize the mixture.

The .alpha.-bromo acids useful in the process are, for, example bromoalkanoic acids having from 2 to 6 carbon atoms. Thus, .alpha.-bromoacetic, .alpha.-bromopropionic, .alpha.-bromobutanoic, .alpha.bromopentanoic and the like acids maybe employed.

Alkali metal nitrites useful in the process are sodium and potassium nitrites. It is believed that the function of the magnesium ion is to form a chelate intermediate which can then be decomposed by the addition of a mineral acid, decarboxylating the alkanoic acid moiety. Ionizable magnesium compounds useful in the process are magnesium alkoxides, such as magnesium methoxide, magnesium sulfate, magnesium chloride or bromide.

Both the magnesium compound and the nitrite are employed in a molar equivalent amount based on the moles of bromo acid used. In order to insure complete reaction of the halo acid a slight excess of each of these is employed. The reaction to form the chelate is considered complete upon the substantial disappearance of the nitrite, i.e., the amount equivalent to the bromoacid.

Aprotic solvents employed are selected from amides and sulfoxides, e.g., dimethyl formamide and dimethyl sulfoxide.

EXAMPLE 1

To a mixture of magnesium methoxide (0.11 mole) and dimethyl sulfoxide (50 ml) .alpha.-bromopropionic acid (0.11 mole) ws added at 20°C. with stirring. To this mixture a solution of sodium nitrite (0.145 mole) in dimethyl sulfoxide (65 ml) was added at room temperature. Then, the reaction mixture was stirred at room temperature for 6 hours and was neutralized upon addition of diluted hydrochloric acid. Analysis of the reaction mixture indicated more than 99% conversion of .alpha.-bromopropionic acid and 94.5% yield of nitroethane.

EXAMPLE 2

In the manner of Example 1 sodium nitrite, .alpha.-bromopropionic acid and magnesium methoxide were reacted in dimethyl sulfoxide as the aprotic solvent. The reaction time was 2 hours for one run and 22 hours for another. Reaction was conducted at room temperature. The run at 2 hours converted only 94.5% of the acid and yielded 72.7% nitroethane. The second run at 22 hours gave a conversion of >99% and a yield of 100%.

At room temperature the reaction apparently takes about 4-5 hours to go to completion. At higher temperatures of 40°C. up to about 75°C. the reaction time is shorter. Thus, one or two hours or even less time at 75°C. will completely convert the bromoacid to the intermediate which can then be decomposed to the nitroalkane.

When using dimethyl sulfoxide as solvent temperatures approaching 100.degree. C. should be avoided since the solvent will volatilize and decompose at about 100.degree. C. Other aprotic solvents may not have this disadvantage.

RedMonn_16

  • Guest
Overseas suppliers.
« Reply #44 on: November 28, 2002, 01:23:00 PM »

roger2003

  • Guest
Method 2: from diethyl sulfate and sodium nitrite ...
« Reply #45 on: November 30, 2002, 08:47:00 AM »
Method 2: from diethyl sulfate and sodium nitrite

Initial run - Into a stoppered bottle was placed a mixture of diethyl sulfate (120g) and sodium nitrite solution (120g in 160ml of water.) The bottle was shaken mechanically for 20 hours, the pressure being released at intervals. The contents were then poured into a separating funnel, and the upper layer separated, dried over calcium chloride. and distilled at 14 mmHg, the distillate up to 60°C being collected (the residue, ca. 230g., consisted of ethyl sulphate and was used again). The distillate was fractionated at atmospheric pressure, and the fraction of bp 114-116°C collected. This was shaken with water, dried over calcium chloride, run through charcoal, and redistilled; bp 114-115.5°C. Yield, 17.7g. (31%, or allowing for recovered ethyl sulfate, 43.5%).

Routine run - A second experiment was then carried out using the same quantity of ethyl sulfate as above. The recovered nitrite solution (lower layer) from the first run was concentrated by adding approximately 16 g. of sodium nitrite per 160ml of solution. Yield 26.4g (46%, or allowing for recovered ethyl sulphate, 65%). For each additional subsequent run approximately 16 g. of nitrite per 160 ml of solution were added, although this represents a rather diminishing concentration in view of the increased yield of nitroethane



The bottle was "shaken mechanically" for 20 hours

Does this procedure also run, if the mixture is stirring in a stainlees steel vessel in larger amounts?


roger2003

Rhodium

  • Guest
Yes, it will run even if stirred, and not shaken.
« Reply #46 on: November 30, 2002, 10:14:00 AM »
Yes, it will run even if stirred, and not shaken. Just make sure you have vigorous stirring, and it won't be much different. I don't have the original article handy right now, but I think I remember the authors saying that the reaction could get out of hand if scaled up too much, pay attention to the second sentence about pressure building up! It might be necessary to run the reaction in a closed system though, I have a hunch that maybe the reaction will produce more ethyl nitrite gas and less nitroethane if run open to the atmosphere. Increased pressure favors the formation of nitroethane.

lugh

  • Guest
Phlorglucinol synthesis details
« Reply #47 on: December 04, 2002, 03:20:00 AM »
From Perkin:

Phlorglucinol is best prepared by fusing one part resorcinol with six parts sodium hydroxide for about twenty five minutes, or until the vigorous evolution of hydrogen has ceased; the chocolate colored melt is dissolved in water, acidified with sulfuric acid, extracted with ether, the ethereal extract evaporated, and the residue recrystallized from water  :)

senzualus

  • Guest
NO3 -> NO2 ?
« Reply #48 on: December 24, 2002, 09:49:00 PM »
I've just got my hands on some benzaldehyde and since I can't get or make Et-NO2(can't find anywhere DMF or DMSO or any of the reactives in the posts)things are getting a bit frustrating..so please give some sugestions:

-I belive that by nitration of ethanol (with HNO3 & H2SO4 analog nitroglycerine nitration)one should get Et-ONO2. Right?

-is it posible to reduce the -ONO2 group to -NO2 using the stoichiometric amount of reduced iron or hydrazine/HO[/sup]- to get nitroethane?

-there must be a way to get speed somewhat OTC other than the cinnamic acid route?


Polverone

  • Guest
careful
« Reply #49 on: December 24, 2002, 11:41:00 PM »
If my recollection of The Chemistry of Powder and Explosives is correct, ethanol can be nitrated only by using pure, nitrous acid-free nitric acid. Nitrous acid contamination or the use of mixed acid may both lead to explosive reactions. But that doesn't really matter, because I'm pretty sure that reduction of ethyl nitrate will lead to ethyl nitrite, not nitroethane. The oxygen that you want to remove is stuck between the nitrogen atom and a carbon, but you're going to end up removing one of the oxygens that's just dangling off of the nitrogen.

19th century digital boy

Rhodium

  • Guest
Nitroethane from ethanol
« Reply #50 on: December 26, 2002, 01:51:00 AM »
Treatment of ethanol with nitric acid will give ethyl nitrate (EtONO2), but this is a sensitive explosive similar to nitroglycerin, so please don't do that. Treatment of ethanol with NaNO2 and H2SO4 will give ethyl nitrite (EtONO)1 with then in turn can be isomerized to nitroethane (EtNO2)2.

1:

https://www.thevespiary.org/rhodium/Rhodium/chemistry/eleusis/nitrites20.html


2:

https://www.thevespiary.org/rhodium/Rhodium/chemistry/nitrite2nitro.html


Aurelius

  • Guest
Ethyl nitrite to Nitroethane
« Reply #51 on: December 26, 2002, 06:46:00 PM »
aurelius prefers this instead- much more efficient and less hassle than setting up a industrial reactor (furnace) and safer too (in aurelius' opinion, at least for newbees)

US Patent 4,319,059

Post 382212

(Rhodium: "US Patent  4,319,059", Chemistry Discourse)


senzualus

  • Guest
heterogenous reaction? (sorry 'bout the spelling)
« Reply #52 on: December 28, 2002, 03:15:00 PM »
What if someone would put in an Erlenmeyer flask some halogenated alkane (like Et-Cl or Et-Br) and then add an xs of NaNO2 and just let it sit there for a couple of days?

I think the reaction time would be somewhat long but probably some kind of (acid?) catalist may be used -like ZnCl2? or a little HCl or HBr?- to accelerate the transformation.

I don't know about any secondary reactions that may occur but I think the general idea is pretty good  :P  and may be worth trying.

I experimented once but by some reason (at that time I did not need any nitroethane) I flushed it down the toilet  ;D  !
Unfortunately,  now I'm waitin' to go to school since I don't have any NaNO2 left  ;) ...

If anyone tries this please post the results :) .

Rhodium

  • Guest
Result of Ethyl Halide & NaNO2
« Reply #53 on: December 29, 2002, 05:30:00 AM »
You would end up with a combination of "it didn't work" and "ethyl nitrite was formed"...

El_Zorro

  • Guest
So what about this? http://www.rhodium.ws/chemi...
« Reply #54 on: December 29, 2002, 05:53:00 AM »
So what about this?

https://www.thevespiary.org/rhodium/Rhodium/chemistry/alcohol2nitro.html



It said that they reported making several simple aliphatic nitroalkanes from nitrous acid and the alcohol via in situ generation of the nitrous by adding HCl to NaNO2.  Could it really be as simple as reacting EtOH with nitrous acid and getting the nitroethane?



Rhodium

  • Guest
wrong claim
« Reply #55 on: December 29, 2002, 06:08:00 AM »
I meant to remove that. Synlett published an article to refute the claims from that article. They were apparently mistaken, only the alkyl nitrites were formed, not the nitroalkanes.

https://www.thevespiary.org/rhodium/Rhodium/pdf/nitroalcohol.pdf




El_Zorro

  • Guest
Weeeeell, shit. It looked so easy....
« Reply #56 on: December 29, 2002, 06:28:00 AM »
Weeeeell, shit.  It looked so easy....  I guess I should have figured it was too good to be true.


senzualus

  • Guest
:-(
« Reply #57 on: December 29, 2002, 09:59:00 PM »

Aurelius

  • Guest
Patent References US patent 4319059
« Reply #58 on: January 09, 2003, 04:58:00 PM »
Hope these are appreciated, takes a while to type them.

US 4319059

Preparation of Nitroalkanes

Abstract:

A process for making nitroalkanes in which an alpha-bromoalkanoic acid is reacted with an alkali metal nitrite, e.g. NaNO2, in the presence of the magnesium ion (Mg++) in an aprotic solvent to form a chelate.  Neutralization of the chelate with a mineral acid produces a nitroalkane having one less carbon atom than the reactant bromoalkanoic acid.


Other related Patents
US 2117931
US 3014972
US 3038015

Notes on the Reaction

aprotic solvent is used.  e. g. dimethyl sulfoxide
Mg compound can be MgSO4 (Epsom salts)
Use alpha- bromopropionic acid to receive nitroethane as major product
Potassium or sodium nitrites may be used
The catalyst (Mg compound) and the nitrite are used in slight molar excess
When the nitrite has been consumed in a molar amount equal to the initial molar amount of the bromoacid, the reaction can be considered complete.

Example 1:

To a mixture of magnesium methoxide (0.11mole) and dimethyl sulfoxide (50ml), alpha-bromopropionic acid (0.11mole) was added at 20*C with stirring.  To this mixture a solution of sodium nitrite (0.145mol) in dimethyl sulfoxide (65ml) was added at room temperature.  Then, the reaction mixture was stirred at room temp for 6 hours and was neutralized upon addition of diluted HCl.  The product was analyzed on a 3’x3/16” Poropak Q Column for nitroethane at 150*C and on a 3’x3/16” column packed with 10% ethylene glycol adipate and 1% phosphoric acid on Chromosorb AW 80/100 mesh for alpha-bromopropionic acid at 150*C.  This analysis of the reaction mixture indicated more than 99% conversion of alpha-bromopropionic acid and 94.5% yield of nitroethane.

Example 2:

In the manner of Example 1, sodium nitrite, alpha-bromopropionic acid and magnesium methoxide were reacted in dimethyl sulfoxide as the aprotic solvent.  The reaction time was 2 hours for a single run and 22 hours for a separate single run.  Reaction was conducted at room temp.  The run at 2 hours converted only 94.5% of the acid to yield 72.7% nitroethane.  The second run at 22 hours gave a conversion of >99% and a yield of 100% (QUANTITATIVE!!!!!)

At room temp the reaction apparently takes about 4-5 hours to go to completion.  At higher temps of 40-70*C the reaction time is shorter.  Thus, one or two hours (or even less at 75*C) will completely convert the bromoacid to the chelate to be decomposed to nitroethane by acidification with HCl.

When using dimethyl sulfoxide as solvent temperatures reaching 100*C should be avoided.  The solvent tends to volatize and decompose (violently) at 100*C.  Other aprotic solvents may not have this disadvantage.

Aurelius

  • Guest
Patent References US patent
« Reply #59 on: January 09, 2003, 05:00:00 PM »
US Patent 4431842

Catalytic Preparation of Nitroalkanes

Abstract:

A process of making nitroalkanes which comprises reacting a lower alkanol, e.g. methanol, and nitric acid (HNO3) in the vapor phase in the presence of a catalyst which is an oxide or a salt of a metal of Group II of the periodic table, e.g. Calcium Chloride.


Other related patents
US 2844634
US 2905724
US 3272874 – uses vapor phase nitration with nitric acid or nitric oxides with oxygenated sulfur compounds such as SO2 and H2SO4.
US 3113975- same as US 3272874 but includes the use of ozone.
US 3780115- nitration of paraffins by nitrogen peroxide (NO2)2 in the presence of oxygen (air) under pressure at 150-330*C.
US 3706808- reacting an olefin with nitric acid in the presence of a lower aliphatic monocarboxylic acid anhydride to produce a nitroester, subsequently reducing it with an alkali borohydride to form the nitroalkane.
US 3113975- use of ozone on amines to form nitro compounds

Representative Preparation of Catalyst

A catalyst was made by immersing an alumina support* in an amount of aqueous CaCl2 solution sufficient to completely wet it.  Excess water was evaporated and the catalyst dried.  The amount of CaCl2 supplied was sufficient to provide a 21% by weight  loading on the support.  Portions were calcined under a nitrogen purge (oxygen excluded) at 150*C, 415*C, 500*C, 600*C and 700*C each for a period of 4 hours.

* This was low surface area (<1 m^2/g) spherical support of medium porosity manufactured by Norton and designated SA-5205.

Example 1:

The different portions of the above prepared catalysts were run in the four foot reactor system.  Methanol conversion differed only slightly, varying rom about 13%-22% for the reaction run at 245*C, 5.5 sec contact time with a MeOH/HNO3/N2 ratio of 4/1/24.  Selectivity varied considerably for the reaction under the above conditions as is shown below in tabular form.

--------------------------------------------------------------------------------------------------------------------------
   Calcination Temp (*C)         % Selectivity to CH3NO2                
150   27
415   35
500   40
600   44
700   67
-------------------------------------------------------------------------------------------------------------------------


Not suggested as a practical method of home production of nitroalkanes.  This method was only posted for posterity.



Aurelius

  • Guest
Other Patents
« Reply #60 on: January 09, 2003, 05:20:00 PM »
After having given an example of a vapor phase nitration/oxidation, aurelius sees no point in typing out the remainder of similar type patents as they (for the most part) have no practical side when compared to the other methods available.  However, here are more patents numbers for those interested in researching the area furthur. 

(all us patents)
1967667
2071122
2206813
2161475
2597698
2609401
3113975


Aurelius

  • Guest
Some Reference Materials in the Compilation
« Reply #61 on: January 16, 2003, 07:24:00 PM »
Nitroethane references:

The titles for these articles are not the actual titles, just brief explanations of the method.


JACS (1954) 76, 4494:

t-butylamine (100g) is added to a solution of KMnO4 (650g) in water (3L) over a period of 15 minutes.  The temperature rose to 45*C.  The mixture was stirred vigorously for 8 hours after which the heat was raised to 50-60*C for another 8 hours.  After the heating is over, the mixture is steam distilled.  The product is washed with dilute HCl acid then dH2O.  The residue is taken up in a non-polar solvent and dried with MgSO4 and the solvent removed under reduced pressure.  The mostly-pure product is then vacuum distilled to give t-nitrobutane (117g, 83% yield).  BP: 127-128*C; n28D=1.3980; MP: 25-26*C

(this article also makes mention of basic H2O2 as a possibility for the same reaction)


JACS 9(1956) 78, 4003:

Solvent mix is usually made as 80% acetone and 20% water with the pH being controlled using MgSO4.

258g of t-octylamine (0.2mol) is dissolved in 500ml of acetone.  Then 125ml of H2O is added.  The mixture is stirred to uniformity.  Then, 30g of MgSO4 is added to form a slurry.  The suspension must be stirred vigorously for best results.  Then, add 190g of KMnO4 over the course of 1 hour.  Stir the mixture for 48 hours at 25-30*C and then steam distill the product.  The blue colored (as a result of presence of nitroso compounds from side reactions) crude product is taken up in petroleum ether (35-37*C fraction), dried with MgSO4 and then fractionally distilled. The final yield of pure t-nitrooctane is 24.3g (yield 77%).  BP: 54*C; n28D= 1.4314


JACS (1957) 79, 5528:

Use of peracetic acid for oxidation of amines to the respective nitro compounds.

CH3COOOH + amine --> Nitro (for aliphatic and aromatics!)

Yields using this procedure from (amine oxidized listed):

Aniline                         83%
p-toluidine                   72%
o-toluidine                   70%
p-anisidine                   82%
t-octylamine                 87%
cyclohexylamine          70%
sec-butylamine             65%
n-hexylamine*             33%

*the low yield in this instance is reasoned to be a result of isomer/tautomerization of the various intermediates reacting in various ways.  This not expected in other primary amines.

Note: The stronger the acid being used to form the per-acid, the greater the need to use a buffer in the form of a base to prevent the adverse effects of full protonation of the amine.

A solution of 60.5ml (0.36mol) trifluoroacetic acid anhydride is placed into a cooled 8.2ml portion of 90% strength H2O2 (0.3mol) in 50ml of DCM.  This solution is stirred for 5 minutes and cooled to –25*C.  This solution is then added to a suspension of 85g (0.8mol) of Na2CO3 in 400ml of DCM at –25 to –35*C over the course of 30 minutes.  Then, add 5.0g (0.005mol) of n-hexylamine in 10 ml of DCM dropwise over another 30 minutes period.  While keeping the solution at –30*C, stir the solution mixture for another 30 minutes.  The pour the mixture into 500ml of H2O, shake, then separate off the organic layer.  The organic layer is then dried with MgSO4 and the solvent is removed.  The residue is distilled under reduced pressure to yield 7.9g (80%) n-hexyltrifluroacetic amide*.

*the formation of the amides is unique to the use of per-trifluroacetic acid for the oxidation.  If another acid, such as peracetic acid, is used, the nitro compound should be formed. 


JOC (1979) 44, 659-661:

General Procedure for the Oxidation of Amines Using m-Chloroperbenzoic acid:

4.1g of m-Chloroperbenzoic acid (0.02mol, 85% purity) is dissolved in 30 ml of solvent in a 3-neck flask fitted with a condensor and a pressure equalized addition funnel.  0.005 mol of the amine to be oxidized is dissolved in 3-5ml of the solvent and is added dropwise to the refluxing peracid solution.  The reaction is allowed to take place with refluxing for 0.5-3.0hours.  After the reaction time is finished, the solution is cooled and the mix is filtered.  Then, the solution is washed 3x50ml of 1 N NaOH and then once more with dH2O to remove traces of NaOH.  The solution is dried with MgSO4.  The solvent is removed under vacuum and the residue distilled under reduced pressure to give the nitro compound in high enough purity for most applications. 

The solvent may be CHCl3, DCM, or DCE in that order with respect to preference according to average yields using said solvents. 


JOC (1992) 57, 25, 6759-6764:

General Procedure for the oxidation of amines to their respective nitro compounds using DMDO in a buffered acetone solution:

0.05mol of the amine is placed in a slurry of 10g of NaHCO3, 30ml of H2O, 30ml Acetone and 30ml of DCM.  A slurry of DMDO in acetone is added in a very large excess until the amine has been consumed (checked with TLC).   The product is extracted from the filtered mixture using ether.  The ether is washed with H2O, then brine.  After the washings, the ether is dried with MgSO4, the solvent is evaporated and the residue distilled to give the Nitro compound. 

The DMDO must be used in large excess to effect the full oxidation to the nitro compound.  K2CO3 may be used in place of the NaHCO3 as a buffer. 


JOC (1985) 50, 16, 2849:

An oxidation of Pyridine to its oxide is included in the article, but that procedure will be posted in a separate thread.

General Preparation of Oxone/DMDO Slurries:

Oxone (28g, 45 mmol) is placed in acetone (100ml) and stirred at 50*C for 16 hours. The slurry is now ready for use. 

Oxidation Potential of the above Slurry:

Aldehydes to acids
Alcohols to Acids
Sulfides to Sulfones
Alkenes to Epoxides


Tetrahedron (1995) 51, 41, 11305-11318:

Preparation of CrS-2 (Chromium silicalite-2):

Gels of composition;  SiO2:xCr2O3:0.4TBAOH:30H2O are hydrothermally synthesized by crystallization at 443K for 90 hours followed by calcination at 773K for 5 hours.  This gave CrS-2 with a Si:Cr of 140:1.


General Procedure for oxidation of amines w/o phototropic rearrangement:

Aniline (0.93g, 10mmol) is added to CrS-2 (93mg, 10%wt/wt) and 70% TBHP (t-butylhydroperoxide)(4.5ml, 33mmol) in methanol (25ml) and was refluxed for 4 hours.  The progress was monitored with TLC.  The solution was filtered and then distilled to give nitrobenzene (1.13g, 92% yield).  (Works for aliphatics also; 1-aminobutane was oxidized in 80% yield to 1-nitrobutane.)


Tet. Lett. (1981) 22, 18, p 1655-1656:

NaMnO4-H2O in Hexane at 69*C for 24 hours is used to oxidize t-butylamine to t-nitrobutane in 76% yield.



Tet. Lett. Vol 27, No. 21, p 2335-2336 (1986):

Oxidation of n-butylamine using DMDO:

n-butylamine (0.052g, 0.7mmol) in 5 ml of acetone is treated with 95ml of 0.05M DMDO in acetone.  The mix is stirred for 30minutes at RT.  No light is permitted to enter the reaction for the extent of the oxidation.  The mix is filtered, washed with a dilute, weak base.  The solvent is dried with MgSO4, then the solvent is removed.  The residue is distilled under vacuum to give 87% 1-nitrobutane.


JOC 17 (1952) 906: Vapor-phase nitration of butane w/O2 present
                          pg 935: Effect of Br2 on Vapor-Phase Nitration of Propane
                          pg 942: Effect of Cl2 on Vapor-Phase nitration of Propane with HNO3



Aurelius

  • Guest
New stuff
« Reply #62 on: May 27, 2003, 10:12:00 PM »
This is totally sweet, I can't thank you enough for this addition.  It's great! Have you attempted any of these synths?  especially the acetaldehyde oxime?

Lego

  • Guest
Unfortunately not.....
« Reply #63 on: May 28, 2003, 01:13:00 AM »
Unfortunately none of these synthesis has been tried by Lego but she is pretty sure that they will work with acetaldehyde oxime, too. Perhaps one day a bee interested in new methods will try this.......

Some words on these methods:

The oxidation with acetonitrile as solvent has the disadvantage of not being OTC but on the workup would be easy. The formed nitroalkane can be destilled from the rest of the mixture.
Acetonitrile is, as far as Lego remembers, prepared from acetamide and oxone, so at least in theory still OTC.

The oxidation with perborate and acetic acid uses OTC chemicals but destillation is near to impossible because the boiling points of acetic acid (118°C) and nitroethan (115°C) are too close. Treating the acetic acid with base will dissolve enough of the formed nitroethane to make separation difficult.

As far as Lego can see these method still propose an interesting route to nitroethane which is hard to get for too many bees.


Aurelius

  • Guest
Sodium borate
« Reply #64 on: May 28, 2003, 03:53:00 AM »
why not partition the acetic acid/nitroethane between water and some organic solvent.  The acetic acid can be extracted from the nitroethane over the course of several washes. (recovered later as an acetate then distillation)

jimwig

  • Guest
No 436362 nitroethane revisited again too...
« Reply #65 on: June 04, 2003, 10:48:00 PM »

Post 436362

(jimwig: "nitroethane revisited again too", Chemistry Discourse)


found this - similar if not exactly like No.1 ---anywho here goes

Nitroethane
H.Krause

Patent CH75523


Aug l, 1917

A mixture of ethyl sulfate and a nitrite is heated with the addition of an agent promoting the formation of nitroethane. e.g. EtNaSO4 + H2O and 100 g. NaNO2 are mixed in a finely powdered state, and this mixt. is thoroughly moistened with a solution of about 7 g. anhydrous soda in about 30 g. H2O. The mixt. is liquefied by heating, and then storngly heated with stirring. At about 115-120 (degrees) nitroethane distils with the H2O with the silmultaneous production of EtNO2 and acetaldehyde. These latter escape, partly the gaseous form, in case the app. is not strongly cooled. After the salt mixt. is dry the heating is continued until oil no longer goes over. In order to expel the last traces of nitroethane, the of the salt mass is allowed to rise to about 200 (degrees). The distillate seps. into an oily and an aq. layer, the former consisting chiefly of nitroethane which, however, because of its content of specifically lighter compds., such acetadehyde and EtNO2 , usually floats upon the H2O........etc.

Abstrated in CA 12, p41, (1918)

the swiss patent is available on Espace in German -(I think its German)
 

translation por favor....???   
===================================================  
Sorry guess i posted this in the wrong place first.

Organikum

  • Guest
Translation
« Reply #66 on: June 05, 2003, 03:27:00 AM »
is found here:

Post 436963

(Organikum: "Patents on nitroethane - translation", Chemistry Discourse)


I believe it would have been sufficient to link and to start a new thread as these monsterthreads are quite unhandy. Aurelius will make a compendium on it sooner or later anyways. (I hope he will!  :) )


Aurelius

  • Guest
Aurelius' Compendiums
« Reply #67 on: June 05, 2003, 05:46:00 PM »
Compendium on what specifically?  I've already made one on nitroethane (needs a couple of recent additions, but not many) Are you talking about making the Compendium into a digest to be edited?  (thought about doing that so I can keep up with new additions)  A little clarification please. (BTW, I don't mind doing the work to make a new one, or revise an old one.)

Organikum

  • Guest
make one which can be found ?
« Reply #68 on: June 06, 2003, 03:10:00 PM »
Neither "compendium" nor "nitroethane" as subject with "aurelius" as poster came up with the "not linked in the post before" compendium.

buhuuu !


Airelius you post definitivly to much to go on further: LINK IT!
pleaze?


Aurelius

  • Guest
link
« Reply #69 on: June 06, 2003, 09:24:00 PM »

Post 355380

(Aurelius: "newest method", Chemistry Discourse)


or

https://www.thevespiary.org/rhodium/Rhodium/chemistry/nitroethane.html



Either works pretty well for me.

Rhodium

  • Guest
Digest
« Reply #70 on: June 07, 2003, 12:31:00 AM »
Yes, please make it into a digest - where you link to old posts containing different procedures instead of cutting and pasting them into the digest.

Aurelius

  • Guest
Rhodium
« Reply #71 on: June 09, 2003, 04:58:00 AM »
Give me a while and I'll make this one up.  I'm pretty busy the next couple of weeks.  Had some stuff come up.

Aurelius

  • Guest
Found in old post
« Reply #72 on: June 11, 2003, 02:48:00 AM »
Don't remember who posted it, but

Nitroethane from acetaldoxime:

J.H. Boyer / H. Alul, Am.Soc. 81, 4237 (1959)


Aurelius

  • Guest
Additional refs
« Reply #73 on: June 11, 2003, 02:51:00 AM »
For method 6:


Method 6
N.Kornblum / R.J. Clutter, Am.Soc. 76, 4494 (1954)

http://www.orgsyn.org/orgsyn/prep.asp?prep=cv5p0845


N.Kornblum / R.J. Clutter / W.J. Jones, Am.Soc. 78, 4003 (1956)

Also found in old post- not sure who though. (too lazy to look it back up)


carbon13

  • Guest
Method 6 should be removed.
« Reply #74 on: June 13, 2003, 05:57:00 AM »
Method 6 should be remove from the Compilation of Nitroethane Syntheses.  Permanganate will not oxidize ethylamine to nitroethane. This method only works with tert-carbinamines.  This is from the book "The Oxidation of Organic Compounds by Permanganate Ion and Hexavalent Chromium" by Donald G. Lee page 88. "If the primary amine contains a hydrogen on a carbon adjacent to the nitrogen, oxidation takes place at this point and instead of nitro compounds the products are aldehydes."  Based on this information, I would doubt that Method 18 would work either.

Aurelius

  • Guest
Post excerpt
« Reply #75 on: June 13, 2003, 07:22:00 PM »
I've personally read 90%+ of the references I've listed and I don't remember ever having a problem with any that made it onto this page.  I'm not claiming that your wrong, I'd just like to make sure before removing anything.


roger2003

  • Guest
German Patent
« Reply #76 on: June 14, 2003, 08:21:00 AM »

Organikum

  • Guest
wrong number
« Reply #77 on: June 14, 2003, 02:51:00 PM »
does not exist.

The posting of plain numbers without any comment in a for most bees not readable language is a major pain in the ass. Adding three lines comment isn´t to much demanded IMHO.

thanks.
O.


roger2003

  • Guest
Nazi Method
« Reply #78 on: June 15, 2003, 01:10:00 PM »
It was the Nazi Method for the production of nitroethane from  CH3CH3 and NO2 with tetraethyl-lead as catalyst

moo

  • Guest
:-S
« Reply #79 on: June 15, 2003, 01:58:00 PM »
::)


jimwig

  • Guest
nitroethane via silver and pottasium nitrite
« Reply #80 on: June 21, 2003, 11:47:00 PM »
Found this similar reaction for nitroethane as already posted but a little different. Also this is essentially the translation of the Berichst (sp?) publications which are in a language I am trying to understand.

======================================================
Organic Preparations --(engklish translation) Weygand
page 292

"A mixture prepared from seperate warm water solutions of 2400g of silver nitrate and 1500g of potassium nitrite is cooled and the crystal of silver nitrite are washed with water and dried. The silver nittrite (2090g) is placed in a large flask equipped with an efficient reflux condenser and dropping funnel, and 1700g of ethyl iodide are added slowly, without shaking, at such a rate that the reaction mixture continues to boil. The reaction is completed by heating the flask for a short time on a water bath. On fractionattion of the reaction mixture, a yield of 50% of the theoretical amount of nitroethane is obtained; it boils at 111 to 113C. Ethyl nitrite is presumably formed as a by-product, most of which escapes on account of it low boiling point (17c).

Kissel and Gotting slowly add the calculate amount of silver nitrite to ethyl iodide at a low temperature; any heating must be avoided. The mixture is allowed to stand for 1 day in cold water and is then fractionated in a current of carbon dioxide. The fractions boiling below 100c yield additional amounts of nitroethane if treated again with silver nitrite. No yield is given, but according to V Meyer it amounts 50% of the theoretical."

(originally from)
V. Meyer and Lockher Ber.,7,1510 (1874);9,539 (1876); ann.;180,140 (1876)

roger2003

  • Guest
Nitroethane from chloropropionic acid
« Reply #81 on: November 06, 2003, 03:50:00 AM »
The synthesis was dicussed

Post 236612

(malvaxman: "Nice nitroethane synth by WizardX", Methods Discourse)
:

also as method 11 in aurelius compilation

Post 438964

(Aurelius: "Compilation of Nitroethane Syntheses", Methods Discourse)
:

and by rhodium

https://www.thevespiary.org/rhodium/Rhodium/chemistry/nitroethane.html



and uemura

Post 236627

(uemura: "Re: Nice nitroethane synth by WizardX", Methods Discourse)
: works with yields from about 20%, because he thinks the corresponding Nitomethane synthesis yields 40%

If you start the synthesis with with 2-chloropropionic acid - CAS 598-78-7 - you get a better yield,  the corresponding nitromethane synthesis yields over 90% if you work with

Patent DE767509

, because the chloroacetic acid was neutralized with MgCO3


The synthesis with alpha bromopropionic acid (2-bromopropionic acid) yields also about 90% (Method 17) but the workup is not easy


Lego

  • Guest
Nitroalkanes from bromoalkanes with PTC
« Reply #82 on: December 02, 2003, 10:40:00 PM »
Thanks to Azole for copying, scanning and hosting this article!




Org. Prep. Proc. Int., 1988, 20(6), 598-599

Synthesis of nitroalkanes from bromoalkanes by phase-transfer catalysis



Submitted (07/30/87) by Pramodchandra V. Sane and Man Mohan Sharma
Department of Chemical Technology
University of Bombay, Matunga
Bombay 400019, India

1-Nitropropane, an intermediate for ethambutol, is usually manufactured by the vapour phase nitration of propane, which unfortunately is hazardous and leads to the formation of various side-products depending on the reaction conditions1. The recent use of nitrite form of basic anion exchange resin for the the synthesis of 1-nitropropane , from the corresponding bromide, involves long reaction periods and low selectivity2. A number of methods for the nitrite desplacement with phase-transfer catalyst (PTC), crown ethers, polyethylene glycols and tetraalkylammonium salts, have been reported; the selectivity for nitrooctane varied between 20% and 70% depending upon the reaction conditions and PTC employed3-5.

For the synthesis of nitroalkanes from bromoalkanes and sodium nitrite, using chloroform as solvent, the liquid-liquid rather than liquid-solid mode of operation was required and it was necessary to maintain alkaline conditions by the addition of 0.4 M sodium carbonate. Several PTC were tried and tetrabutylammonium hydrogen sulfate (TBAHS) worked best; of a number of solvents tried, chloroform was found to be the best. The main by-product formed was the alkyl nitrite and hydrolysis to the alcohol was negligible. Thus in 6 hrs, with TBAHS as PTC, the yield of 1-nitropropane was 62% and 23% of unreacted 1-bromopropane was revovered; propyl nitrite was detected to the extent of 14%. Under the same conditions as for 1-bromopropane, the yield of 1-nitrobutane was 57% with 26% recovery of unreacted 1-bromobutane. By contrast, with 1-chlorobutane, under similiar conditions as above, no reaction to 1-nitrobutane occured. 1-Nitrohexane was obtained in 45% yield and 39% of unreacted 1-bromohexane was recovered. Further, with 2-bromopropane the rate was relatively low and the yield of 2-nitropropane was 24% and the recovery of unreacted 2-bromopropane was 65%.

Experimental section

1-Nitropropane
The reaction was conducted in a fully baffled mechanically agitated glas contactor of 100 ml capacity provided with a glass impeller at 31°. To an aqueous phase solution (60 ml) of sodium nitrite (25 g, 0.36 mol) and sodium carbonate (2.55 g, 0.024 mol), an organic phase consisting of 1-bromopropane (10 ml, 0.11 mol) and TBAHS (tetrabutylammonium hydrogen sulfate) (1.12 g, 3.3 mmol) in chloroform (10 ml) was added. The reaction mixture was stirred at a constant speed of agitation of 1500 rev/min. The progress of the reaction was monitored by analysing samples from the organic phase by gas-liquid chromatography; an s.s. column, 3.2 mm dia. x 2 meter long, packed with 10% SE-30 on Chromosorb-W, was used with nitrogen, as a carrier, on a "Chemito" gas chromatograph. After 6 hrs, the reaction mixture was worked up and the residue distilled to yield 6.0 g (61% yield) of 1-nitropropane, bp. 55°/40 mm. The product ws structurally confirmed through an FT-IR (Bruker, IFS 88) and 1H-NMR (Varia EM-360L, 60 MHz).

1H-NMR-data: ...

Acknowledgement: ...


References
1. H. B. Hass, E. B. Hodge, B. M. Vanderbilt, Ind. Eng. Chem., 28, 339 (1936); H. B. Hass and H. Shechter, ibid., 39, 817 (1947)
2. G. Gelbard and S. Colonna, Synthesis, 113 (1977)
3. J. W. Zubrick, B. I. Dunbar and H. D. Durst, Tetrahedron Lett., 71 (1975)
4. K. Matsunaga and T. Yamashita, Kogyo Kayaku, 41, 3 (1980); C. A. 94, 3167g (1981)
5. C. Kimura, K. Kashiwaya and K. Murai, Asahi Garasu Kogyo Gijutsu Shoreikai Kenkyu Hokoku, 24, 59 (1974); C. A. 84, 121027 (1976)


Organikum

  • Guest
addon to jimwigs post
« Reply #83 on: December 03, 2003, 01:16:00 PM »
regarding the preparation of nitrites:

Post 458114

(gruns: "Preparation of Sodium Nitrite: Discussion", Chemicals & Equipment)

I sadly didnt find a proofen procedure for the preparation of nitrites from nitrates using starch - perhaps my searching skills.....

Lego

  • Guest
Primary alkyl halides to nitroalkanes in water
« Reply #84 on: September 25, 2004, 12:18:00 AM »
The First Conversion of Primary Alkyl Halides to Nitroalkanes under Aqueous Medium
Roberto Ballini, Luciano Barboni, Guido Giarlo
J. Org. Chem., 2004, 69(20), 6907-6908
DOI:

10.1021/jo049048b




Abstract: Primary nitroalkanes and alpha, omega-dinitroalkanes can be easily obtained in aqueous medium by reaction of the corresponding halo derivatives with silver nitrite. The procedure works well with both alkyl bomide and alkyl iodide and proceeds in satisfactory to good yields even in the presence of other functionalities, minimizing the formation of the undesired alkyl nitrites.




Experimental Section: To a water solution (2 mL) of the iodoalkane (1 mmol) was added AgNO2 (4 mmol) and the reaction flask was wrapped with silver paper to protect the reaction mixture from light. After being stirred at the appropriate temperature (see Table 1), the reaction mixture was filtered, extracted with EtOAc, and dried over Na2SO4 and the solved was evaporated under reduced pressure. The crude products were purified by column chromatography (hexane:EtOAc, 95:5). To verify the efficiency of the reaction in a larger scale, we tested, as a representative example, the conversion of 1h (20 mmol) to 2h, without significant changes of both the reaction time and yield. As a criterion of purity, 1H NMR or 13C NMR spectra of the compounds prepared are reported in the

Supporting Information

(http://pubs3.acs.org/acs/journals/supporting_information.page?in_manuscript=jo049048b).


azole

  • Guest
vapor phase nitration of paraffins (refs.)
« Reply #85 on: October 12, 2004, 08:15:00 AM »
Here is a collection of articles on the topic. Some of them are mentioned in this thread (e. g. methods 14 and 15 in

Post 355380

(Aurelius: "newest method", Chemistry Discourse)
); some were requested by Hex, who experimented with propane nitration in a tube furnace (

Post 534811 (missing)

(Hex: "Íèòðîïàðàôèíû äåñòðóêöèîííûì íèòðîâàíèåì ïðîïàíà", Russian HyperLab)
).


Nitration of Gaseous Paraffins
H. B. Hass, E. B. Hodge, and B. M. Vanderbilt
Ind. Eng. Chem., 1936, 28, 339-344.



Reaction Mechanism for Nitrating Paraffin Hydrocarbons
Rush Fox McCleary, Ed. F. Degering
Ind. Eng. Chem., 1938, 30, 64-67.



Nitration of n-Pentane
H. B. Hass and J. A. Patterson
Ind. Eng. Chem., 1938, 30, 67-69.



Vapor-Phase Nitration of Saturated Hydrocarbons
H. B. Hass and H. Shechter
Ind. Eng. Chem., 1947, 39, 817-821.



Nitration Studies. I. General Mechanism of Vapor Phase Nitration
G. B. Bachman, L. M. Addison, J. V. Hewett, L. Kohn, and A. Millikan
J. Org. Chem., 1952, 17, 906-913.



Nitration Studies. II. Effect of Oxygen on the Vapor Phase Nitration of Butane
G. B. Bachman, H. B. Hass, and L. M. Addison
J. Org. Chem., 1952, 17, 914-927.



Nitration Studies. III. Effect of Oxygen on the Vapor Phase Nitration of Propane with Nitrogen Dioxide
G. B. Bachman, H. B. Hass, and J. V. Hewett
J. Org. Chem., 1952, 17, 928-934.



Nitration Studies. IV. Effect of Bromine in the Vapor Phase Nitration of Propane
G. B. Bachman, J. V. Hewett, and A. G. Millikan
J. Org. Chem., 1952, 17, 935-941.



Nitration Studies. V. Effect of Chlorine in Vapor Phase Nitration with Nitric Acid
G. B. Bachman and L. Kohn
J. Org. Chem., 1952, 17, 942-954.


xxxxx

  • Guest
i once read somewhere...
« Reply #86 on: October 21, 2004, 06:38:00 AM »
i once read some where that the sodium salts of nitroparafins could be alkylated with alkyl halides, if a large excess of nitroparafin (5x) was used to prevent polyalkylation. maybe someone could verify this with nitromethane, sodium ethoxide and the methylating agent of their choice.