Nitroalkanes from Me/EtCl and aq. NaNO2!

[Antoncho]

Hi, guys!

Just in case anyone is still interested in making EtNO2 or MeNO2 some easy OTC way ...

I found a patent (2,105,581) on uspto.gov that describes preparation of nitromethane from CH3Cl and aq. NaNO2. Methyl chloride is bubbled into vigorously boiling sat. NaNO2 soln. at pH 6-10 (CaCO3 used as buffer) with stirring (it says "suitable means of securing intimate contact between gas and the soln.") and preferrably a foaming agent (any form of soap) to increase the rxn surface. Nitromethane is continuously fractionally distilled from the rxn as its azeotrope w/water (bp 82 C) - it slows down the rxn if it's not. Additional water and NaNO2 should be periodically added to the rxn mixtr.
The patent says the invention may be applied for production of any other alkylnitrate as well. It doesn't state the yield specifically, but it's been my impression that it's high since a) the proc. was developed as an industrial process of MeNO2 manufctring b) only 10% of methyl nitrite is formed. So... Here you go, my beloved fellow bees. As easy as it gets. That is, if it works - i tend to cross my fingers lately when i say smth like this  
SWIM won't be around for 2 or maybe three weeks so he can't check it right now. Maybe some people you met (esp. the ones possessing stirrer hotplates ) can do a trial run or two of this inexpensive and promising procedure?

Here's the link to the full patent image (AlternaTiff plug-in required): 

http://patimg2.uspto.gov/.piw?Docid=02105581&homeurl=http%3A//164.195.100.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=%272%2C105%2C581%27.WKU.&OS=PN/2%2C105%2C581&RS=PN/2%2C105%2C581&PageNum=&Rtype=&SectionNum=&idkey=1B10F8A8CC23

(jesus is it supposed to be that long???)
and the .tiff plug-in (190 Kb):

http://www.mieweb.com/alternatiff/distribution/alternatiff-1_3_7.exe

Thank you all in advance,
Antoncho

[PrimoPyro]

ummm im confused. what i know about nomenclature makes me think i detect an error, but on the other hand i trust the findings of such experienced ppl.......

my problem: CH3Cl  +  NaNO2  --> CH3NO2  +  NaCl
Thats fine. BUT CH3NO2 produced this way is methyl nitrite, NOT nitromethane.

NaNO2 = Na-O-N=O
methyl nitrite = CH3-O-N=O meaning N valency = 3
nitromethane = CH3-N=O;=O meaning N valency = 5

See the difference? am i missing something everyone else understands and i don't? right now i don't think so. enlighten me.

sorry im not being clear: i mean why in the world would only 10% methyl nitrite be formed? why would ANY nitromethane be formed at all? its just a simple electrophilic substitution right?
Of COURSE we don't know what we're doing! That's why it's called research!  (boom...)    

[obituary]

that all depends on rxn conditions and the solvent- depending on solvent you can change whether the Oxygen or Nitrogen attacks the carbon.  therfore, a different product can be obtained by the different use of solvent.

[PrimoPyro]

ic. thanx. can u either explain how that mechanism works, or give me a search criteria? im not above doing my own research, but i didnt know this at all and i dont know WHAT to search for? im just asking what would u look for? thanx. i really appreciate ur time.
Of COURSE we don't know what we're doing! That's why it's called research!  (boom...)    

[obituary]

obit wishes that obit could find that link again- there is a page that describes the formation of nitrates and nitrites (organic) and a little bit about the mechanism- mostly just search for those two key words and maybe something like "synthesis of...." or "formation of...."  and you'll probably find it

[Rhodium]

The only difference between making an alkyl nitrite and an alkyl nitrate is if the alkylation happens on oxygen or nitrogen. There is no real valency difference here. In nitrates, the nitrogen is mostly R-N⁺(O)-O^-, which don't imply an oxidaton compared to R-N=O.

[terbium]

between making an alkyl nitrite and an alkyl nitrate

Don't you mean nitroalkane (RNO₂) rather than alkyl nitrate (RNO₃)?

[Rhodium]

Of course, I'm just tired right now

[jim]

The usual nitroalkane synthesis from organohalides and NaNO2 is with DMF or DMSO, and they have rather high yields, so why use this method?

[Rhodium]

Because it does not make use of the aforementioned solvents, just water, and thus makes the aquisition of the needed chemicals easier. Also, this seems to be more easily scaleable than the DMF/DMSO routes, as the products are more easily separated from water, and water is free.

[obituary]

DMF may be a pain to get but DMSO seems to be "somewhat" readily available- in the right places anyway.

[PrimoPyro]

Thanx guys for the info, I appreciate it.
Of COURSE we don't know what we're doing! That's why it's called research!  (boom...)