Selective reductive annulation reaction for direct synthesis of functionalized quinolines by a cobalt nanocatalyst

Due to the extensive applications of quinolines, the search for selective construction of such products has long been an attractive subject in scientific community. Herein, by developing a new N-doped ZrO2@C supported cobalt nanomaterial, it has been successfully applied as an efficient catalyst for the reductive annulation of 2-nitroaryl carbonyls with alkynoates and alkynones. The catalytic transformation allows synthesizing a wide array of funcitonalized quinolines with the merits of broad substrate scope, good functional group tolerance, excellent hydrogen transfer selectivity, reusable earth-abundant metal catalyst, and operational simplicity. The developed chemistry paves the ways for further design of hydrogen transfer-mediated coupling reactions by developing heterogeneous catalysts with suitable supports. (C) 2020 Elsevier Inc. All rights reserved.