Vicinal dianions of diethyl α-aroylsuccinates: a general synthetic route to α-aroyl- and α-arylidene-γ-butyrolactones

Vicinal dianions derived from diethyl α-aroylsuccinates were found to react with carbonyl compounds β-regioselectively to afford α-aroyl-γ-butyrolactones, which were converted into α-arylidene-γ-butyrolactones by reduction with H2/Pd–C followed by elimination employing methanesulfonyl chloride in pyridine. The method provides a general and convenient route to α-aroyl- and α-arylidene-γ-butyrolactones.