Stereoselective preparation of Z-trisubstituted alkylidene cyclic carbonates via palladium-catalyzed carboncarbon bond formation

Alkylidene cyclic carbonates bearing a Z-trisubstituted exocyclic double bond have been stereoselectively prepared in good yields for the first time from methylene cyclic carbonates, resistant to the classical Heck reaction, on treatment with aryl iodides, CF3CO2Ag and palladium catalyst, under conditions which tolerate (sp2)CBr bonds.