Highly Stereoselective Synthesis of 2,2-Disubstituted Vinylphosphonates via Aryl to Vinyl 1,4-Palladium Migration

Vinylphosphates play an important role in the fields of synthetic chemistry,pharmaceuticals and material science.It is a long-standing challenge to control the geometry of multi-substituted vinylphosphates.Herein,an efficient method for the synthesis of 2,2-disubstituted vinylphosphonates has been reported.The reaction proceeded via aryl to vinyl 1,4-palladium migration progress,in which two difficulties that the deactivation of palladium catalyst by the coordination of excess secondary phosphine oxide and the competitive cross-coupling to form arylphosphonates are successfully overcome.The judicious selection of phosphine ligand is the key to success.This protocol features excellent regio-and stereoselectivitiy,generally excellent reaction yields and broad substrate socpe.