One‐Pot Synthesis of 3‐Alkylidenephthalides from Benzoic Acids by a Rhodium‐Catalyzed ortho‐CH Acylation Process

CH functionalization: A [Rh(cod)Cl]2/CsF (cod=1,5-cyclooctadiene) catalyst system was found to promote the straightforward synthesis of 3-alkylidenephthalides from benzoic acids and aliphatic acids or anhydrides through a one-pot CH acylation/acylalization/elimination cascade (see scheme).