Direct synthesis of γ‐substituted phthalides <i>via ortho</i>‐aryl benzoic acid mediated benzyl radical cyclization

Abstract

Abstract Direct synthesis of γ‐substituted phthalids from related ortho ‐aryl benzoic acids with 48–85% yield are covered. The direct oxidation in the presence of peroxydisulphate‐copper (II) chloride in aqueous medium was applied. The reaction is highly regioselective and leads exclusively to γ‐butyrolactone, through very stable benzylic radical intermediate.