B(C6F5)3-Catalyzed transfer hydrogenation of esters and organic carbonates towards alcohols with ammonia borane

Abstract

Herein, we report an efficient metal-free system for the transfer hydrogenation of esters and carbonates by-passing the otherwise ubiquitous formation of transesterification side-products. The Lewis acid B(C₆F₅)₃ is used as catalyst and ammonia borane as hydrogen donor. This methodology shows broad substrate scope and functional group tolerance in excellent yields at very mild conditions.