Sciencemadness Discussion Board

Coupling of amine to amide

bucketshop - 18-3-2009 at 10:36

Hi guys, I'm trying to couple a primary amine to a formamide group and I'm really struggling with the purification. I'm using phosphorous oxychloride and I cannot get the product pure.

Does anyone have any suggestions for other methods of coupling?

Thanks in advance

Donna

Coupling of amide to primary amine?

bucketshop - 18-3-2009 at 14:25

I posted this in general chemistry by accident, it'd probably get more more replies here!

Hi guys, I'm trying to couple a primary amine to a formamide group and I'm really struggling with the purification. I'm using phosphorous oxychloride and I cannot get the product pure.

Does anyone have any suggestions for other methods of coupling?

Thanks in advance

Donna

Ebao-lu - 18-3-2009 at 14:56

What you mean by coupling a primary amine to a formamide group? Formylation of amine, or making a formamidine R-N=CH(NR'R'')?
In you want to formylate amine, you can reflux it with ethylformiate.
Amidines can me made like amide + P2S5 = thioamide, thioamide + amine = amidine

[Edited on 18-3-2009 by Ebao-lu]

bucketshop - 18-3-2009 at 15:47

Joining the two together to make R-N-C=N-R, sorry if that wasn't clear.

chemrox - 18-3-2009 at 22:11

I turned this up on a brief search. I hope it is as helpful to you as it would seem to me.

[Edited on 18-3-2009 by chemrox]

Attachment: amide bonds & coupling reagents.pdf (1MB)
This file has been downloaded 5756 times

Ebao-lu - 19-3-2009 at 03:29

Here are some common routes http://img18.imageshack.us/img18/7196/amidine.jpg I think if you have same Rs, then it is preferable to use the last method with CH(OEt)3.


[Edited on 19-3-2009 by Ebao-lu]

Ebao-lu - 19-3-2009 at 03:43

Quote:
Why not tell what your target is and what your reactants are.

w-18?