J. Xu, C. Shen, X.L. Zhu, P.F. Zhang, M.J. Ajitha, K.W. Huang, Z.F. An, X.G. Liu
Volume 11, Issue 6, 882-892, (2016)
Achieving site selectivity in carbon–hydrogen (C−H) functionalization reactions is a formidable challenge in organic chemistry. Herein, we report a novel approach to activating remote C−H bonds at the C5 position of 8-aminoquinoline through copper-catalyzed sulfonylation under mild conditions. Our strategy shows high conversion efficiency, a broad substrate scope, and good toleration with different functional groups. Furthermore, our mechanistic investigations suggest that a single-electron-transfer process plays a vital role in generating sulfonyl radicals and subsequently initiating C−S cross-coupling. Importantly, our copper-catalyzed remote functionalization protocol can be expanded for the construction of a variety of chemical bonds, including C−O, C−Br, C−N, C−C, and C−I. These findings provide a fundamental insight into the activation of remote C−H bonds, while offering new possibilities for rational design of drug molecules and optoelectronic materials requiring specific modification of functional groups.