Ruthenium-Catalyzed Synthesis of Phthalides in Water via C-H Alkenylation

Significance

Reported is a concise synthesis of phthalides from benzoic acids and α,β-unsaturated nitriles or esters, involving ruthenium-catalyzed cross-dehydrogenative alkenylation and subsequent intramolecular oxa-Michael reaction. Remarkably, the process is accomplished in water under mild conditions to afford the phthalides in moderate to excellent yields. However, the reaction scope and limitations were not well investigated.