alpha- and beta-substituted N,N-diethylacrylamides undergo copper-mediated direct beta-trifluoromethylation. The amide moiety acts as a directing group for the regio- and the stereo-controlled introduction of the trifluoromethyl group. The reaction is carried out under acidic conditions in the presence of Umemoto's reagent. This method does not require prefunctionalized substrates and delivers excellent stereoselectivity.
Rhenium‐Catalyzed Decarboxylative Tri‐/Difluoromethylation of Styrenes with Fluorinated Carboxylic Acid‐Derived Hypervalent Iodine Reagents
作者:Yin Wang、Yunhui Yang、Congyang Wang
DOI:10.1002/cjoc.201900296
日期:2019.12
Herein, unprecedented rhenium‐catalyzed decarboxylative oxytri‐/difluoromethylation and Heck‐type trifluoromethylation of styrenes have been developed by using hypervalent iodine(III) reagents derived from cheap, stable, and easy‐handling fluorinated carboxylic acids. Mechanistic studies revealed a radical decarboxylative trifluoromethylation pathway occurring in these reactions.