C(sp3)–H Carboxylation via Carbene/Photoredox Cooperative Catalysis

C(sp3)–H bond functionalization is a powerful strategy for the synthesis of organic compounds due their abundance in simple starting materials. Photoredox catalysis has led to a diverse array of enabling C(sp3)–H activation strategies; however, a general platform for the direct functionalization of C(sp3)–H to carboxylic acid derivatives remains elusive. Disclosed herein is the development of a cooperative NHC/photoredox-catalyzed C(sp3)–H esterification transformation. This method enables access to benzylic, α-heteroatom, and formal β-esterification products in moderate to high yields under mild reaction conditions.