Base promoted regio- and stereoselective hydrophosphinylation of allenes

Abstract

A novel and transition-metal-free hydrophosphinylation of allenes with secondary phosphine oxides was developed. In the presence of the cheap and commercially available cesium carbonate, various hydrophosphinylation products were synthesized with exclusive regio- and stereoselectivity under mild conditions. This methodology provides simple and efficient access to (E)-alkenylphosphine oxides in moderate to excellent yields with a relatively broad substrate scope.