Author Topic: What can be done to improve the performance of clandestine nitroethane synth?  (Read 10992 times)

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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.