BINOLates as potent reducing photocatalysts for inert bond activation and reduction of unsaturated systems

Abstract

Phenolates are increasingly studied as photocatalysts because of their abundance and easy accessibility. However, their potential as potent and broadly applicable reducing photoredox catalysts is hindered by the high electronegativity of oxygen and the reactivity of phenoxy radicals. Herein, we discovered that renowned 1,1′-Bi-2-naphtholate derivatives (BINOLates) are potent reducing photocatalysts. These catalysts are effective for the activation of inert bonds and the reduction of unsaturated bonds, including selective CF activation of activated –CF₃,–CF₂H, –C₂F₅, and aryl fluoride, activation of alkyl and aryl chlorides, detosylation, Birch reduction, and alkene reduction, demonstrating potent reducing ability and catalytic versatility. Defluoroalkylation using PhCF₃ as a limiting reagent, a challenging substrate for reported catalysts, proceeded smoothly. BINOLates were applicable as photoredox catalysts even under green light. This work introduces a new catalytic application for the renowned BINOLates, suggesting the potential for future expansion of their applications in the realm of photocatalysis.