Ag-Catalyzed Selective C-C Bond Activation of Cyclopropenones to Access α-Alkylidene Lactones.

A novel Ag-catalyzed ring opening of unsymmetric cyclopropenones for the stereoselective synthesis of a diverse range of α-alkylidene lactones has been developed. In this protocol, two different C-C(O) bonds were distinguished, demonstrating selective C-C bond activation. This reaction features a wide substrate scope, good functional group compatibility, and high atom economy, providing a versatile and general approach to the construction of α-alkylidene lactones.