Ru(II)-Catalyzed C-H bond activation/annulation of N -iminopyridinium ylides with sulfoxonium ylides.

A Ru(II)-catalyzed C-H bond activation/annulation of N -iminopyridinium ylides with sulfoxonium ylides has been developed for the synthesis of diverse functionalized isocoumarin derivatives. This method features broad substrate scope, high functional group tolerance, simple operation and silver salt-free conditions. Furthermore, the synthetic utility of this method is demonstrated by the alkenylation of the product and efficient synthesis of biologically active thunberginol A.