Also known as: Perkin condensation
The Perkin reaction is an organic reaction used to convert an aromatic aldehyde and an anhydride to an α,β-unsaturated carboxylic acid using sodium acetate, a base, and an acid work-up. The regiochemistry of the reaction, the relative position of the carboxylic acid and aromatic ring in the final product, can be either E or Z. The mechanism goes through numerous steps including several additions and eliminations.
Perkin, W. H. J. Chem. Soc. 1868, 21, 181