Sciencemadness Discussion Board

Synth or Source of 2-Nitropropane

Darkfire - 14-6-2004 at 21:32

Im gonna be in need of some iso-nitropropane. I've checked the Hive and Rhodium but i cant find anything and im afraid to ask there. Can anybody body here hook me up with a link?

Polverone - 14-6-2004 at 22:00

Isopropyl bromide + silver nitrite?

thunderfvck - 14-6-2004 at 22:06

Would this work?

Isopropyl alcohol and nitric acid with concentrated sulfuric acid..

(CH3)2CHOH + HNO3 --conc. H2SO4--> (CH3)2CHNO2 + H2O

or maybe with any nitrate salt?

Edit, what kind of catalyst doesn't have its protons regenrated! With this pathway that I've proposed, 2 H2SO4's will lose a proton, one in dropping off the H2O from the isopropyl and the other in forming the nitro electrophile. Even worse with the nitrate salt, three!

Hmmm?

[Edited on 15-6-2004 by thunderfvck]

[Edited on 15-6-2004 by thunderfvck]

Darkfire - 14-6-2004 at 23:48

I think that gives isopropal nitrate, ^^^?

thunderfvck - 14-6-2004 at 23:53

Fuck.

[Edited on 15-6-2004 by thunderfvck]

I am a fish - 14-6-2004 at 23:54

Quote:
Originally posted by thunderfvck
(CH3)2CHOH + HNO3 --conc. H2SO4--> (CH3)2CHNO2 + H2O


That equation isn't balanced. There are 4 oxygen atoms on the left hand side, but only 3 on the right.

Such a reaction would yield isopropyl nitrate.

(CH3)2CHOH + HNO3 --conc. H2SO4--> (CH3)2CHONO2 + H2O

thunderfvck - 14-6-2004 at 23:55

Sorry, TWO waters...and I'm at loss about the hydrogens. Hence my confusion.

But yeah, isopropyl nitrate. Gotcha.

[Edited on 15-6-2004 by thunderfvck]

Darkfire - 15-6-2004 at 00:10

I can see poleverons method working, but i could use KNO2 and expect like 50/50 yeilds of 2-nitropropane and 2-isopropal nitrite?

This should happen with both Ag and K nitrites although Ag gives slighty better yeilds. So how are these gonna be seperated? I dont think distilation would work.

thunderfvck - 15-6-2004 at 00:17

How about this slice of pineapple?

(CH3)2CH2OH --conc. H2SO4--> (CH2)2CH3 + H2O

(CH2)2CH3 + HNO3 --conc. H2SO4--> (CH3)2CHNO2 + H2O

BUT, the hydrogens don't balance for the latter equation..You'd have to seperate isomers as well. AND methylethene is a gas, a flammable gas which isn't very soluble in water...

I don't know! But I am having fun trying..!:D

Polverone - 15-6-2004 at 09:24

Quote:
Originally posted by Darkfire
I can see poleverons method working, but i could use KNO2 and expect like 50/50 yeilds of 2-nitropropane and 2-isopropal nitrite?

This should happen with both Ag and K nitrites although Ag gives slighty better yeilds. So how are these gonna be seperated? I dont think distilation would work.


Hmm, I thought that KNO2 would give very little of the nitro compound, unless you ran the reaction in DMF or DMSO. KNO2 is a real pain to try to make on your own with any sort of purity, so you probably have to buy it, and it seems rather more expensive/hard to find than NaNO2. So I'm not sure how much easier/cheaper it is to use KNO2 than AgNO2. The silver nitrite can easily be made from silver metal, HNO3 (to make AgNO3) and NaNO2 (to double-exchange and form far-less-soluble AgNO2). Silver salts are pretty easy to recover and recycle.

Isopropyl nitrite has a much lower BP than nitropropane. They should easily separate by distillation.

Edit: If you're really ambitious (crazy), you can also pass propane through 99% HNO3, heat the vapor mixture in a tube, and produce a mixture of nitromethane, nitroethane, and nitropropanes (like it's done industrially).

[Edited on 6-15-2004 by Polverone]

Darkfire - 15-6-2004 at 10:03

I meant NaNO2, my o-cem book, shows 60% yeilds, and AgnO2 shows 80%.

S.C. Wack - 15-6-2004 at 12:26

Are those yields for this cpd? I would love to know any reference it gives if it is.

Kornblum got a 19-26% yield of 2-nitropropane using the Victor Meyer (Ag nitrite) in JACS 77, 5528 (1955), from isopropyl bromide. He's had a few articles published on nitro cpds, so I am inclined to believe him.

The yields of secondary nitroalkane are generally better with the modified version, using the Na or Li nitrite/DMF or DMSO route. Although this cpd. is not in these papers, for illustration:
https://www.rhodium.ws/pdf/nitroethane.kornblum.dmf.pdf
https://www.rhodium.ws/pdf/nitroethane.kornblum.dmso.pdf

I didn't think that you or anyone else would be interested in the original prep (in German) so I didn't paste it, but might as well mention that it is Meyer and Chojnacki, Ber., 5, 1034 (1872)

Darkfire - 15-6-2004 at 15:16

Whats cpd?

I read my yeilds on page 732 ofthe third edition or Organic Chemistry by Clayton Heathcock and Andrew Steitwieser Jr.

Whoopsie daisy.

Polverone - 15-6-2004 at 16:01

I went back and looked at a review article, and my suggestion to use AgNO2 was off. It fares very poorly with secondary alkyl halides.

Darkfire: your chem book's figures appear to be for saturated primary alkyl halides. The use of DMF or DMSO as a solvent when employing NaNO2 and alkyl halide is necessary, because both the alkyl halide and the NaNO2 need to be dissolved in relatively high concentrations for the reaction to work reasonably.

With secondary alkyl halides (especially), nitrosation can take place, decreasing yields of the nitro compound unless workup is prompt. Adding a nitrite scavenger like phloroglucinol stops this reaction and makes reaction/workup easy.

The article I'm reading this information from is "The Synthesis of Aliphatic and Alicyclic Nitro Compounds" by Nathan Kornblum, found as Chapter 3 of Volume 12 in Wiley's "Organic Reactions" series.

Darkfire - 15-6-2004 at 18:01

Thanks for the help, whats the sugested amount of DSMO relitive to the IsoPropylBromide and NaNO2 in that book?

[Edited on 16-6-2004 by Darkfire]

2 stage

Turel - 15-6-2004 at 23:39

1.Acetone and hydroxylamine reduction with zinc and acid.

2.Oxidation of 2-aminopropane with DMDO in acetone, yielding 2-nitropropane.

t_Pyro - 16-6-2004 at 00:58

The following method might work:
nitromethane+NaOH+chloromethane->nitroethane
nitroethane+conc NaOH+chloromethane-> 2-nitropropane

The first step takes place easily, but the second step will be less spontaneous.

kaboom

Turel - 16-6-2004 at 01:29

1.Tendency for substitution increases with each consecutive substitution, and you will end up with 2-nitro-tert-butane.

2.NaOH forms dangerous explosive salts with nitroalkanes......

Darkfire - 16-6-2004 at 10:46

I was thinking similar Turel, but

1. Reductive amination of acetone with Hg/Al and an amine source (NH4OH?)

2. Oxydation with KMnO4

Interesting

Turel - 16-6-2004 at 14:45

1.You will need an anhydrous ammonia source, and will need to saturate the solution with ammonia before adding your ketone, or you will run into multiple issues.

2.Im not sure how well or not well this will work. KMnO4 concatonates nitrogens from primary amines so that 2RNH2 ---> R-N=N-R but I see no reason that KMnO4 would not further oxidize the diimide to nitroso intermediates, well on their way to nitro compounds. I don't know.

Darkfire - 16-6-2004 at 14:47

I just saw a little tidbit metioning that on rhodium so i though id bring it up.

unionised - 17-6-2004 at 12:05

Can you get nitropropane by methylating nitromethane twice?

franklyn - 27-10-2013 at 19:04

I have the thought that producing 2-nitropropane can be achieved under milder conditions than refluxing a toxic sulfate ester with a nitrite salt by using instead this addition compound of Acetone and Sodium bisulfite ( NaHSO3 )
www.citychemical.com/acetone-sodium-bisulfite.html ( can't understand why it's so expensive )
made as described here _
http://www.erowid.org/archive/rhodium/chemistry/eleusis/bisu...
http://en.wikipedia.org/wiki/Sodium_bisulfite
https://worldwidejanitor.com/marine-products-c-84/sodium-bisulfite-p-210
This can be reacted in solution with Sodium Nitrite , NaNO2 + C3H7NaSO4 => Na2SO4 + CH3.CH(NO2).CH3
and possibly get 2-nitropropane or perhaps only nitrite ? Both salts have good solubility in water.

.