Author Topic: question about Nitroethane-synths  (Read 7758 times)

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evil_emma

  • Guest
question about Nitroethane-synths
« on: December 04, 2003, 01:52:00 AM »
After reading a whole lot in here about the synthesis of Nitroethan, I still have a couple of questions that I need you bees to help me out with  :) .

The synth wich interests me the most (both due to the yield & the chems used) is #3 in Aurelius compilation. It uses sodium nitrit & ehtyl bromide in DMSO. The reading is great but has anyone here any experience with this synth? I read in Total Synthesis II that this synth doesn´t work out without using Phloroglucinol as nitrite scavenger? Does it, or does it not? If it has to be used, can urea (as said in Aurelius #3) be used as nitrite scavenger as well as Phloroglucinol? Urea is alot easier to obtain than Phloroglucionol.

Aurelius #3 tells us urea can be used when using DMF as solvent, but I guess that if it CAN be used -it would work out i DMSO as well? (DMF not available where swim lives).

Also, has anyone tried performing this in ethylene glycol instead of DMSO/DMF? This synth uses ALOT of solvent, so it would be cheaper to be able to use it.

And what is really the appropriate volume of solvent (DMSO)? Aurelius #3 uses 600ml DMSO/36,5g ethylbromide/36g sodium nitrite & Ritter uses almost exactly the same amount of ethyl bromide/sodium nitrite, but only 250ml DMSO (+52g. Phloroglucinol). Using 600 ml DMSO (wich by my knowledge is not possible to recycle out of this solution) is going to be VERY expensive when synthesising liters of Nitroethane! So what is really the minimum amount that could be used?

I would really appreciate all help I can get on this one!

Rhodium

  • Guest
original nitroethane literature
« Reply #1 on: December 04, 2003, 08:55:00 AM »
It seems like you need to read the original literature on this topic. The limiting factor is the solubility of sodium nitrite in the solvent used.

A New Method for the Synthesis of Aliphatic Nitro Compounds (in DMF)
N.Kornblum, H.O. Larson, R.K. Blackwood, D.D. Mooberry, E.P. Oliveto, G.E. Graham

J. Am. Chem. Soc. 78, 1497-1501 (1956)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/nitroethane.kornblum.dmf.pdf)
____ ___ __ _

Synthesis of Aliphatic Nitro Compounds (in DMSO)
Nathan Kornblum, Jack Powers

J. Org. Chem. 22, 455-456 (1957)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/nitroethane.kornblum.dmso.pdf)



Bonus: Nitroethane from propyl nitrate (the goods is in part III, but it references the other two).

The Thermal Decomposition of Nitrate Esters. I. Ethyl Nitrate
Joseph B. Levy

J. Am. Chem. Soc. 76, 3254-3257 (1954)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/nitroethane.propylnitrate-1.pdf)
____ ___ __ _

The Thermal Decomposition of Nitrate Esters. II. The Effect of Additives on the Thermal Decomposition of Ethyl Nitrate
Joseph B. Levy

J. Am. Chem. Soc. 76, 3790-3793 (1954)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/nitroethane.propylnitrate-2.pdf)
____ ___ __ _

The Thermal Decomposition of Nitrate Esters. III. n-Propyl Nitrate
Joseph B. Levy, Frank J. Adrian

J. Am. Chem. Soc. 77, 2015-2016 (1955)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/nitroethane.propylnitrate-3.pdf)

Daphuk_up

  • Guest
Hmm
« Reply #2 on: March 30, 2004, 01:13:00 AM »
SWID apologizes for bumbing this old thread, but he has a few questions and comments he would like to put forth.

First, although SWID is far from a competant chemist, he examined the mechanistics and came to understand how it was actually working.  Then he played with Isopropyl Nitrate, and decided that it would probably produce nitromethane or something else entirely.  He saw one possible route, but doesn't know enough about radical formation and reaction to postulate on the probability.

SWID is thinking that all that is moot anyways, since this is actually pretty unpractical for any sort of clandestine nitroethane production.  He thinks this way because of the low pressures they use...at first he thought they meant 54.2mm above atmospheric.  At 54.2mm total pressure, a 1L container will only be holding 3mmol (according to the ideal gas law).  50% conversion would leave a whopping ~.113g of nitroethane.  Of course, SWID realizes that these posts aren't necessarily intended to cater to the OTC types, but SWID is saying the article is more interesting for the mechanistics than any sort of practical application.

Just for the hell of it, SWID is going to guess that the main intermediaries from isopropyl nitrate, following the formation of NO2 and the CH3CH2(O*)CH3 radical is acetaldehyde and methyl radical.  The methyl radical could then combine with the NO2 to form nitromethane.

SWID also finds it interesting that he can find no mention of the final pressure in the container after "decomposition".  The term is misleading to those (such as SWID) who are still newbees.  What they are really doing is heating the propyl nitrate till it explodes...except at very low pressures so the reaction is still manageable.  "Explosives Research Department, U.S. Naval Ordinance Lab" pretty much says it all.

SWID had high hopes for this...nitroethane with using the ever-so-precious sodium nitrite. :(


Antibody2

  • Guest
huh?
« Reply #3 on: March 30, 2004, 07:27:00 PM »
ever-so-precious sodium nitrite.
25kgs bags of sodium nitrite can be purchased for $50.


Disciple

  • Guest
Ozone
« Reply #4 on: March 31, 2004, 06:39:00 AM »
Does anyone have any experience or literature with the ozone oxidation of ethylamine. It has been hinted at but...

armageddon

  • Guest
nitrite availability
« Reply #5 on: April 16, 2004, 07:00:00 AM »
AB2: there are also countries where sodium nitrite is as hard to get as nitroethane itself. I think it's because they're afraid that people would use it for making explosives.
..or drugs.. ;D


moo

  • Guest
Explosives? Are you sure you are not mistaking
« Reply #6 on: April 16, 2004, 01:14:00 PM »
Explosives? Are you sure you are not mistaking nitrate for nitrite?


armageddon

  • Guest
not sure
« Reply #7 on: April 16, 2004, 04:44:00 PM »
Moo: No, not sure about nitrate/nitrite, but I know that many NOx-things like HNO3, N2O (although for different reasons), ammonium nitrate and yes (I know for sure) even NaNO2 are restricted in european countries due to the many bad things u could do with them.. :)

..or did I miss something important?  :o  (pssst, is there a place where euro bees could get this stuff otc in multiple kilo quantities? ..maybe pottery supplies? please tell me then!  ;) )


moo

  • Guest
You did miss something important, I already...
« Reply #8 on: April 17, 2004, 12:58:00 AM »
You did miss something important, I already told you what it is. It is your own problem if you don't know what you actually need. Read up or miss the goodies.


armageddon

  • Guest
nitrite/nitrate?
« Reply #9 on: April 17, 2004, 03:04:00 AM »
Moo: the only thing you told me so far is that I perhaps may have mistaken nitrate for nitrite... 
this is not the case. I meant NaNO2 being not available OTC. And I surely have no problems with knowing what I need...

(btw what should I read up?)


karl

  • Guest
Some time ago I tried making EtNO2 via the...
« Reply #10 on: April 17, 2004, 05:03:00 PM »
Some time ago I tried making EtNO2 via the EtBr/NaNO2/DMSO route on two occaisions, Only the EtBr was prepared by myself which was distilled before use, and damn me the entire bloody thing set to a solid crystalline mass just before all the EtBr was added. None of the desired product was isolated, complete and utter failure. The DMSO appeared to have been consumed by this reaction. I never worked out went wrong.
Has anyone any suggestion as to what potentially can go wrong with that reaction to give a result like that. If not I can only assume I was sold some mislabelled product.

SpicyBrown

  • Guest
Re: Some time ago I tried making EtNO2 via the
« Reply #11 on: April 21, 2004, 07:38:00 PM »

Some time ago I tried making EtNO2 via the EtBr/NaNO2/DMSO route on two occaisions, Only the EtBr was prepared by myself which was distilled before use, and damn me the entire bloody thing set to a solid crystalline mass just before all the EtBr was added. None of the desired product was isolated, complete and utter failure. The DMSO appeared to have been consumed by this reaction. I never worked out went wrong.




I had very similar results... I also tried this route twice.  The first time I had results very similar to yours, though I produced an incredibly foul smelling product in the course of things.. I'd bet it was a nasty sulfur compound by the horrific stench of it - that smell stuck around the room I tried that reaction in for quite a while as well  :(  I tried it again some time later in the presence of catechol.  Didn't get the unworkable solid, and no horrific smell, but out of the funky brown stew resulting from the attempt came no nitroethane.

Next time I try to make nitroethane damnit, I'm going to give the destructive distillation of 2-chloropropionic acid in the presence of sodium nitrite a try..

-SpicyBrown


Daphuk_up

  • Guest
There is a doc...
« Reply #12 on: April 22, 2004, 05:08:00 PM »
Somewhat recently there was a document (or "technical bulletin") posted on the hive with a large amount of information regarding DMSO.  On page 16 on the left hand side of the table it states that ethyl bromide is miscible with DMSO, but that it reacts.  It doesn't say how though.  SWID suspects that saying that DMSO may be substituted for DMF is another case of logical extrapolation without proper experimentation being reported as fact.  SWID is pretty sure he has had success using DMF (only pretty sure because he roasted the supposed ethylnitronate with concentrated HCl by accident), but using the procedure as stated wastes the DMF...he is looking into recovering it by salting the solution with NaCl, and extracting several times with IPA.  Results will be posted if he gets around to it before it all evaporates. :-[


hest

  • Guest
Nitroethane
« Reply #13 on: April 23, 2004, 04:16:00 AM »
My eksperiment's look likes SpicyBrown's. In my hand the DMSO synt just end's up with a chunk of solid material and no nitroethane (with an without cathecol. all chemicals from Aldrich,fluka ect.) My eksperimet's with DMF as an solvent is the same storie.

karel

  • Guest
Nitroethane synthesis
« Reply #14 on: April 25, 2004, 10:31:00 AM »
I also attepted to synth nitroethane from EtBr and NaNO2 in DMSO with bad yield. I can recommend reaction of EtBr with dry AgNO2 in dry Et2O, which fully satisfied SWIM and gave him about 80 % yield.
It's not difficult to transform AgBr back to AgNO2 (you need zinc wire, HNO3, and NaNO2), SWIM made about a liter of EtNO2 from several hundred grams of AgNO3 (from which AgNO2 is produced).

hest

  • Guest
Nitroethane
« Reply #15 on: April 25, 2004, 10:59:00 AM »
Hey Karel, I would love to hear some more info on your nitroethane synth.

karel

  • Guest
Nitroethane synthesis
« Reply #16 on: April 25, 2004, 04:29:00 PM »
The procedure in

Org. Synth., Coll. Vol. 4, 724

(http://www.orgsyn.org/orgsyn/prep.asp?prep=cv4p0724) was followed with 2 mol EtBr and 2 mol AgNO2. Distillation of the reaction mixture at atmospheric pressure gave ether contamined with EtONO and NOx as a forerun and then 75-80 % yield of EtNO2 boiling at 108-112 C.

Ether containing EtONO was attempted to purify by shaking with dilute HCl and water. Drying with NaOH and then with metallic Na led to reduction of leftovers of nitrogen impurities to ammonia, which was precipitated with concd H2SO4. Ether was after drying with NaOH and then with Na suitable for using in the reaction.
I assume that low-boiling petroleum ether could be good substute for ether, but I didn't try it.

The AgBr precipitate*, which was filtered from the reaction mixture, was allowed to dry in air and suspended in 1000 ml hot water. Diluted H2SO4 was added to destroy nonreacted AgNO2 and NOx were allowed to escape. The addition of H2SO4 was repeated at times to maintain the solution acidic. To slightly acidic hot solution was then added zinc wire** of diameter 3-5 mm. It is advantageous to use this wire as a stirring rod. Immediately after the wire reached the AgBr precipitate, the reduction of black Ag occured at the point of contact. After several hours the reaction was finished; it was necessary to keep solution acidic by occasional addition of H2SO4. Reduced Ag formed characteristic light gray precipitate, which was dried in air.
This Ag was dissoved in cca 20 % HNO3, solution was shortly boiled to remove NOx and excess acid was carefully neutralized with diluted NaOH. The neutral solution was suitable for production of next batch of AgNO2 (see Org. Synth. procedure).

* The mother liquor and washing liquors from AgNO2 preparation were collected and excess of NaCl solution was added to them. Precipitated AgCl was then added to AgBr, so the overall lost of Ag at this 2 molar scale was lower than 1 g.

** Zinc wire was used in excess. It was found to be much better than zinc powder. If slight contamination of Ag with carbon doesn't matter, the steel wire could be also used, but I didn't try it.

SpicyBrown

  • Guest
Karl!
« Reply #17 on: April 25, 2004, 11:23:00 PM »
Holy shit karl, this seems to be a very promising procedure you've just tossed into the mix... Will have to get some AgNO3 and get started on the inorganic side of things..

Why does this work so much better? Is silver nitrite more reactive than sodium nitrite? Something to do with the rather insoluble AgBr formed as a product (as a driving force)? Anybody?

The shitty thing is, I spent hours one day scouring OrgSyn looking for stuff on making nitroalkanes, and managed to miss this entry entirely...

Thanks karl!

-SpicyBrown

xxxxx

  • Guest
nitrostyrene to nitropropene with naoet +ch3cl ?
« Reply #18 on: April 26, 2004, 09:46:00 AM »

xxxxx

  • Guest
nitromethane to nitroethane using naoc2h5 + ch3cl
« Reply #19 on: April 26, 2004, 12:06:00 PM »