Sciencemadness Discussion Board

formaldehyde methylamine and formic acid

Wolf8312 - 25-12-2015 at 02:26

Guys I have been looking at this problem for a while and can’t get my head round it I think it’s one of those mechanisms that I am never going to work out on my own, so could someone point me in the direction of a mechanism?


How does Methyleneimine, water and formaldehyde react to form methylamine and formic acid?


I understand the wider (Formaldehyde/ammonium chloride) synthesis I just don’t understand the mechanism for how the formic acid is produced.

Formic acid acting as a hydride was something I could never have guessed so I am thinking this too will be pretty difficult and although I've jotted down a few ideas I have no idea of knowing if I am right or not.

Many thanks in advance.

Marcelo F - 25-12-2015 at 05:07

The mechanism is the Eschweiler–Clarke reaction

http://www.organic-chemistry.org/namedreactions/eschweiler-c...

Wolf8312 - 25-12-2015 at 06:34

Thanks but that link leaves me with the same problem I am afraid. Like I said in the OP I understand the overall reaction I just don’t understand the exact mechanism in which Methyleneimine, water and formaldehyde react together to form formic acid.

It’s the production of the formic acid that I am wondering about and not the methylamine.

As you can see in the link you provided the exact mechanism for the production of the formic acid isn’t shown. I believe it is created by H20 reacting with another molecule of formaldehyde to create formic acid but am unsure if this is correct or exactly how this happens.

Nicodem - 25-12-2015 at 06:44

Quote: Originally posted by Marcelo F  
The mechanism is the Eschweiler–Clarke reaction

http://www.organic-chemistry.org/namedreactions/eschweiler-c...

No, it is not. I have no clue why he did not use any reference, but I assume he is asking about this OS synthesis:
http://www.orgsyn.org/demo.aspx?prep=CV1P0347
...or its variation using hexamine directly, which is the same thing, more or less.
Quote: Originally posted by Wolf8312  
It’s the production of the formic acid that I am wondering about and not the methylamine.

Formic acid is the stoichiometric by-product and forms as a result of the redox reaction.

The mechanism was never researched as far as I know, though I did not bother actually searching the literature. It is obviously some sort of a disproportionation, kind of like the Cannizzaro reaction, but I the mechanism could be anything. Why do you ask?

Welcome to the forum, but please open beginnings topics only in the Beginnings section. Read the forum guidelines for more information.

Bert - 25-12-2015 at 07:05

The whole pattern of asking a question, claiming to not understand the answer while admitting to knowing about the standard reference/chemistry/physics already & etc. are like a fingerprint- "Oh, it's the "I can't get my head around it" troll guy again".

Do you actually masturbate while doing these, or is the story about your wearing crotchless lederhosen while using the computer apocryphal?

Could you at least come up with slightly different wording?

Wolf8312 - 25-12-2015 at 07:40


Nicodem:
Quote:

The mechanism was never researched as far as I know, though I did not bother actually searching the literature. It is obviously some sort of a disproportionation, kind of like the Cannizzaro reaction, but I the mechanism could be anything. Why do you ask?


So its not that well understood then? Seems to be one of those reactions one has to memorize rather than understand.

No particular reason why I ask dude just couldnt find an answer. I was reading through the methylamine synthesis and the first problem I had was with exactly how the reduction of the imine (Methyleneimine) would occur giving that the reagents did not seem to be sources of hydride or common hydrogen nucleophiles.

I discovered that in fact formic acid was the source of hydride for this reaction and was happy, but then realized that I didn’t have a clue how this formic acid was created and sitting down with a pen and paper to work it all out didn’t help matters much and only increased my frustration.

I just felt without understanding how the formic acid was formed I couldnt really understand the whole reaction.

I searched around the internet for answers and then finally decided to register here to see if I could get some help. Appologies for not being clearer though I just didnt want my intentions to be misunderstood as I am not intending to carry out this synthesis and am just trying to learn.



Bert siad:
Quote:

The whole pattern of asking a question, claiming to not understand the answer while admitting to knowing about the standard reference/chemistry/physics already & etc. are like a fingerprint- "Oh, it's the "I can't get my head around it" troll guy again".Do you actually masturbate while doing these, or is the story about your wearing crotchless lederhosen while using the computer apocryphal?Could you at least come up with slightly different wording?



Sorry dude?





[Edited on 25-12-2015 by Wolf8312]