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Friedel-Crafts acylation with amides.

ABSTRACT: 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.

SUBMITTER: Raja EK

PROVIDER: S-EPMC3402163 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Friedel-Crafts acylation with amides.

Raja Erum K EK DeSchepper Daniel J DJ Lill Sten O Nilsson SO Klumpp Douglas A DA

The Journal of organic chemistry 20120621 13

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 in ...[more]

PMID: 22690740

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