A bifunctional boronic acid/phosphorus(V) organocatalyst for the direct room-temperature amidation of carboxylic acids

Abstract

The sustainable synthesis of amide bonds under mild conditions is a key green chemistry target for the pharmaceutical process industry and is highlighted as one of the ten goals of the American Chemical Society’s Green Chemistry Institute Pharmaceutical Roundtable. Here, we report an organocatalyst that can achieve the synthesis of amides at room temperature. The catalyst includes both boronic acid and phosphine oxide functionalities, which operate in concert to facilitate substrate activation. Unlike that of other arylboronic acid catalysts, the monomeric mechanism proceeds via a redox-neutral phosphorus(V) cycle, where the adjacent boronic acid is key to room-temperature activity.