Transition-metal-free approach to quinolines via direct oxidative cyclocondensation reaction of N, N-dimethyl enaminones with o-aminobenzyl alcohols

Kairui Rao; Zhangmengjie Chai; Pan Zhou; Donghan Liu; Yulin Sun; Fuchao Yu

doi:10.3389/fchem.2022.1008568

Transition-metal-free approach to quinolines via direct oxidative cyclocondensation reaction of N, N-dimethyl enaminones with o-aminobenzyl alcohols

Front Chem. 2022 Sep 21:10:1008568. doi: 10.3389/fchem.2022.1008568. eCollection 2022.

Authors

Kairui Rao¹, Zhangmengjie Chai¹, Pan Zhou¹, Donghan Liu¹, Yulin Sun¹, Fuchao Yu¹

Affiliation

¹ Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China.

Abstract

A transition-metal-free method for the construction of 3-substituted or 3,4-disubstituted quinolines from readily available N,N-dimethyl enaminones and o-aminobenzyl alcohols is reported. The direct oxidative cyclocondensation reaction tolerates broad functional groups, allowing the efficient synthesis of various quinolines in moderate to excellent yields. The reaction involves a C (sp³)-O bond cleavage and a C=N bind and a C=C bond formation during the oxidative cyclization process, and the mechanism was proposed.

Keywords: N; N-dimethyl enaminones; o-aminobenzyl alcohols; oxidative cyclocondensation reaction; quinolines; transition-metal-free.