Friedel-Crafts Acylation

The electrophilic aromatic substitution by an acyl group derived from carboxylic acid derivatives in the presence of a Lewis acid or Brønsted acid is generally known as the Friedel–Crafts acylation. The nitrobenzene is used as the solvent and several acylating agents have been summarized for Friedel–Crafts acylation. Besides this, Lewis acid has also been used in this reaction to increase the electrophilicity of acylating agents. Several catalysts have been found effective when acyl anhydrides are used as acylating agents. The direction of acylation has been reported to follow the Crum–Brown–Gibson substitution rule. Other developments for the Friedel–Crafts acylation have also been discussed.