Sciencemadness Discussion Board

2-butylamine

Mik229 - 12-8-2010 at 08:59

Hello

I was wondering if following synthesis would work for 2-butylamine:

Chloromagnesiumethane + Acetaldehyde -> 2-chloromagnesiumbutoxide

2-chloromagnesiumbutoxide + Ammoniumhydroxide -> 2-butylamine + side products

Could this work or will oxygen react with only hydrogen forming 2-butanol + ammonia?



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Satan - 12-8-2010 at 09:56

No, it would give secondary alcohol. To make amine from "2-chloromagnesiumbutoxide" you need anhydrous ammonia.

And on this forum topics without references are opened in beginnings forum.

Arrhenius - 13-8-2010 at 00:56

No, this won't work, and neither will treating a secondary alcohol with ammonia as suggested by 'Satan'. Think about it. You're suggesting displacing an alcohol with ammonia. Alcohols are not good leaving groups and ammonia is not a very strong nucleophile. You're partly correct, however. The alkoxide will deprotonate the ammonium hydroxide to give the alcohol, a metal hydroxide and ammonia, which will not easily react to give 2-butylamine. This product could be more easily be prepared - conceptually - from methyl ethyl ketone by reductive amination, or by Gabriel synthesis from a 2-halobutane.

Ephoton - 13-8-2010 at 01:36

talk about going the hard way to a compound what a waist of time.

MEK + hydroxylamine in alcohol made freebase by caustic or carbonate.

reduce oxime with acetic acid Al/Hg.

should get around 70 too 80% yeild.

to easy why go the hard way.

Satan - 13-8-2010 at 01:48

Mik229 is trying to simplify something like in this patent: GB782887. And I never said that he should make amine from alcohol with ammonia, but its possible under pressure.

I meant that alkoxide intermediate will react with anhydrous ammonia to give amine and Mg(OH)Cl, according to patent mentioned above.

And talking about waste of time, he never asked about possible routes to make this particular amine :) He asked if hes proposed reaction would work...

Mik229 - 13-8-2010 at 05:50

Thanks for the answers. Reason for my proposed synthesis (if it would have worked) was no need for expensive/hard to obtain reduction agents.

chemrox - 13-8-2010 at 20:11

Hard to obtain? Al foil, acetic acid & HgCl2? and you could reduce that oxime with Zn NH4Cl in MeOH imho

Ephoton - 14-8-2010 at 04:32

yes I belive your right there chemrox.

I have played with a realy nice synth of hydroxylamine that

is posted on wetdreams I sugest if you have an account

you take a look it uses only sulfuric acid and nitromethane

and the yeild is stella. like I can make well over half a kilo

in a day in a 500ml flask.

I think what chemrox has said about the zinc reduction will

work as its a simple alphatic oxime.

OTC chem is not just reading patents its realy

digging into the shops and seeing what chems you can make

extract or buy.

then its all about ways that work reliably and safely as most

people (there are a few on here that are not like this)

are not able to work safely with a lot of compounds and

reaction.

the way that I have stated will not have you working with

realy dangerous chems.

but hey its up to you in the end.