Friedel-Crafts acylation with amides.
Friedel-Crafts acylation has been known since the 1870s, and it is an important organic synthetic reaction leading to aromatic ketone products. Friedel-Crafts acylation is usually performed with carboxylic acid chlorides or anhydrides, while amides are generally not useful substrates in these reactions. Despite being the least reactive carboxylic acid derivative, we have found a series of amides capable of providing aromatic ketones in good yields (55-96%, 17 examples). We propose a mechanism involving diminished C-N resonance through superelectrophilic activation and subsequent cleavage to acyl cations.
Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, USA.
Erum K
EK
Raja
Daniel J
DJ
DeSchepper
Sten O Nilsson
SO
Lill
Douglas A
DA
Klumpp
D000215:Acylation; D000577:Amides / Q000737:chemistry*; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
D000577:Amides; D007659:Ketones