Metal-free C–H borylation of heterocycles by merging photoredox and hydrogen atom transfer catalysis

Abstract

Reported herein is a method that merges organophotoredox and hydrogen atom transfer catalysis to enable the C–H borylation of heterocycles using O₂ as an environmentally friendly oxidant. This straightforward approach exhibits an extensive substrate scope, allowing for the direct utilization of a wide range of heterocycles, including quinoxaline-2(1H)-ones, chromones, quinazolinones, azauracils, and quinoxalines. The synthetic utility of this approach is underscored by its applicability in the late-stage modifications of complex molecules with medicinal relevance.