Sciencemadness Discussion Board

Dimethylamine From Dimethylformamide

chemisch - 3-11-2012 at 16:00

I'm trying to think of the practical issues of the synthesis of dimethylamine as it is a gas obviously soluble in water. Using hydrochloric would work i would assume not sure the concentration 12M or less. Formic acid is also a product and how would i deal with purifying?
thanks in advance

kristofvagyok - 3-11-2012 at 17:49

Basic organic chemistry rule 1: a strong acid will make a salt more readily with a base than a weak acid.

So if you add HCl to the HNMe2, then HNMe2.HCl will be formed and the excess HCl and the formic acid could be distilled out.

Method no2 is to add some NaOH to the methylamine and formic acid solution and here the formic acid will react to give sodium formate and the dimethylamine could be distilled out.

I would recommend the method no1 and convert back the base.HCl with some solid NaOH/KOH and distill the dimethylamine to a dry ice cooled flask (it has a horrible smell, so be careful).

Shouldn't this fit in the beginnings section?

chemisch - 3-11-2012 at 19:30

that makes a ton of sense. thank you.

chemisch - 3-11-2012 at 20:29

Oh, one more quick question how would one attempt to concentrate? because attempting to make a 40% aqs solution sounds difficult

Nicodem - 4-11-2012 at 03:36

The preparation of dimethylamine from DMF has already been described. UTFSE before opening new threads and open threads without references only in the Beginnings section.

chemrox - 24-12-2013 at 00:43

Quote: Originally posted by Nicodem  
The preparation of dimethylamine from DMF has already been described. UTFSE before opening new threads and open threads without references only in the Beginnings section.

I ran multiple searches for this method and got only brief mentions.

Mr_Magnesium - 24-12-2013 at 04:13

Quote: Originally posted by chemrox  
Quote: Originally posted by Nicodem  
The preparation of dimethylamine from DMF has already been described. UTFSE before opening new threads and open threads without references only in the Beginnings section.

I ran multiple searches for this method and got only brief mentions.


http://www.sciencemadness.org/talk/viewthread.php?tid=11634

i was planning on making the compound which pantone posted about :) scroll down a bit and you'll see it.

Which leads to: DMF + NaOH

Heat the solution till gas evolves which leads to another flask and the dimethylamine dissolves in there.

http://www.sciencemadness.org/talk/viewthread.php?tid=9139

http://www.sciencemadness.org/talk/viewthread.php?tid=20361

Just look for the big paragraphs in the threads, there is a write up if you would like to read.




[Edited on 25-12-2013 by Mr_Magnesium]