Transition-Metal-Catalyzed Directed C8–H Carbon–Carbon Bond Formation in Quinolines and 1,2,3,4-Tetrahydroquinolines

Abstract

C8-Substituted quinoline (QN) and 1,2,3,4-tetrahydroquinoline (THQ) scaffolds are featured largely in a plethora of bio-active compounds and natural products. Appreciable efforts have thus been made towards the development of elegant techniques to functionalize the C8-H bond of QNs and THQs. Transition-metal-catalyzed chelation assisted C-H activation strategy has emerged as an effective synthetic tool among existing methods. This review focuses on the recent advances in the transition-metal-catalyzed directed carbon-carbon bond forming reactions for the C8-H functionalization of QNs and THQs (till February 2023). The discussion has been summarized categorically on the type of reactions.