Sciencemadness Discussion Board

Amide N-alkylation?

MeshPL - 20-9-2015 at 00:17

Can amides be N-alkylated? If not, why?

If yes, would the following chain of reactions make any sense?

Benzoyl chloride -ammonia-> Benzamide -2*ethyl chloride/ethyl sulphate-> Diethylbenzamide -LiAlH4-> Benzyldiethylamine

Not that I have required aparature or reagents.

CuReUS - 20-9-2015 at 09:18

Amides can be N-alkylated,but its not easy.IIRC a Boron reagent is needed.
but this paper is interesting
http://www.mdpi.net/molecules/papers/41100333.pdf

Crowfjord - 20-9-2015 at 09:30

That paper does look interesting. Might make for a more amateur-friendly approach to amide alkylation. I've never heard of a boron reagent for that sort of thing. Normally a very strong base like sodium hydride or sodamide is used.

PHILOU Zrealone - 20-9-2015 at 14:05

N alkylation can be done with formaldehyde...
Depending on reaction condition and réactants ratio...
R-CO-NH2 + CH2=O --> R-CO-NH-CH2OH <==> R-CO-N=CH2 + H2O
R-CO-NH2 + 2 CH2=O --> R-CO-N(-CH2OH)2
2 R-CO-NH2 + CH2=O --> R-CO-NH-CH2-NH-CO-R

CuReUS - 21-9-2015 at 10:03

see pg 39 of this books(sadly pg 37-38 cannot be viewed)
https://books.google.co.in/books?id=wPa-s7FgmZ8C&pg=PA84...
Quote:
I've never heard of a boron reagent for that sort of thing

I saw it a few months back so I might have forgotten,I think I saw this(first reaction under "recent literature")
S. A. Rossi, K. W. Shimkin, Q. Xu, L. M. Mori-Quiroz, D. A. Watson, Org. Lett., 2013, 15, 2314-2317.
http://www.organic-chemistry.org/synthesis/C1N/amides2.shtm