Catalytic Borylative Opening of Propargyl Cyclopropane, Epoxide, Aziridine, and Oxetane Substrates: Ligand Controlled Synthesis of Allenyl Boronates and Alkenyl Diboronates

Abstract

Anew copper-catalyzed reaction for the stereo-and regioselective synthesis of alkenyl diboronates and allenyl boronates is presented. In this process propargyl derivatives of strained three/four-membered rings were employed as substrates and B 2 pin 2 was used as the boronate source.S elective formation of the alkenyl diboronate versus the allenyl boronate products was controlled by the choice of phosphine ligand.