RhIII-Catalyzed Regioselective Synthesis of Phthalides with Water as the Solvent

Under rhodium(III)-catalyzed conditions, a broad range of benzoic acids reacted with acrylates successfully to provide phthalides through the direct functionalization of a CH bond followed by beta-hydride elimination and intramolecular Michael addition. The reaction provides an alternative strategy for the construction of diverse and useful phthalide derivatives from readily available starting materials. In most cases, high regioselectivity was obtained, and this is the first report of the rhodium-catalyzed synthesis of phthalides in water.