Perkin Reaction
Perkin Reaction or Perkin condensation
Perkin Reaction or Perkin condensation, is an organic reaction used for the synthesis of α,β-unsaturated aromatic acid by the condensation of an aromatic aldehyde and an acid anhydride, in the presence of an alkali salt of the acid corresponding to the anhydride acting as a weak base. The acid anhydride should have at least two α- hydrogen atoms, if one α- hydrogen atom is present in anhydride then no dehydration is possible and aldol type product is formed. Meta directing groups in the aromatic ring promotes the reaction.Besides simple aromatic aldehyde, their vinylogs, heterocyclic aldehydes and even phathalic anhydrides give this reaction.