Quinoline as an Intramolecular Hydride Shuttle in the Deoxygenative Coupling Reaction of Alcohol and the Inert Methyl C(sp3)-H Bond

J Org Chem. 2024 Dec 20;89(24):18406-18411. doi: 10.1021/acs.joc.4c02269. Epub 2024 Dec 9.

Abstract

Reported herein is the C(sp3)-C(sp3) bond-forming at an unactivated C(sp3)-H bond via hydride transfer-initiated deoxygenative coupling reactions. Various polycyclic hydroquinolines were provided under metal-free conditions with excellent diastereoselectivity. Mechanistic study revealed that quinoline served as an intramolecular hydride shuttle to achieve the hydride abstraction and release in order. This methodology not only provides a practical strategy for direct deoxygenative coupling for the C(sp3)-C(sp3) bond-forming but also develops a new reaction type involving quinoline-enabled hydride transfer.