Photo-Induced Difluoromethylation-Cyclization and Domino Amination-Defluorination to 4-(Aminomethyl)-3-fluoro-quinolinones
Xin Wang, Dongyang Zhao, Jia-Bo Huang, Gangqing Shi, Er‐Jun Hao, Shao‐Fei Ni, Kai Sun
Abstract
Herein, we report a visible light-induced difluoromethylation cyclization and subsequent amination-defluorination reaction. This protocol allows efficient to valuable 3-fluoro-quinolinones in moderate to excellent yields. A sequential difluoromethylation-cyclization-amination-defluorination mechanism was proposed based on a mechanism study. Further density functional theory (DFT) calculations revealed that the base K 2 HPO 4 could lower the energy due to the C═O···K + electrostatic interaction to assist the elimination process, while the six-membered transition state located in situ was essential for the cleavage of N–H and C–F bonds during this S N 2′-type process.