Oxidizing and Transformable Directing Groups in CH Functionalization

Abstract

Transition metal‐catalyzed direct CH activation has been developed as a powerful strategy for the rapid construction of molecular complexity. The ubiquity and strength of CH bonds present major challenges toward the realization of CH transformations: selectivity and efficiency. The directing groups (DGs) resolved the regioselectivity and improved the catalytic activity of metal. However, they always left a chemical trace in the products, which limited the structural diversity. Hence, the development of multifunctional DGs in CH transformations comprised a central issue recently. This article focuses on the recent progress on the multifunctional DGs in transition metal‐catalyzed CH transformations, including oxidizing, migratable, and transformable DGs, which realize a highly atom‐economical process, incorporate the DGs in the final products, and enrich structural diversity of the products. We expect that these strategies will stimulate further innovative studies thought modifying DGs and developing a novel function of DGs, resulting in the discovery of efficient methods for the synthesis of complex molecules.