Ir(III)-Catalyzed Mono-Olefination of Aryl C–H Bonds Using −SCF3 as a Weak Directing Group
摘要:
The trifluoromethylthionyl group (-SCF3) is an efficient weak directing group for Ir(III)-catalyzed aryl C-H olefination. Various trifluoromethylthioethers provide high levels of mono-olefination products in good to excellent yields under mild conditions with a 2,2'-bipyridine ligand or AgBF4 as an additive. Mechanistic studies indicate the C-H cleavage is the rate-determining step. The directing group ability of the -SCF3 group is benchmarked against several other weak directing groups by competition experiments under Ir(III)-catalyzed conditions.
Ir(III)-Catalyzed Mono-Olefination of Aryl C–H Bonds Using −SCF3 as a Weak Directing Group
摘要:
The trifluoromethylthionyl group (-SCF3) is an efficient weak directing group for Ir(III)-catalyzed aryl C-H olefination. Various trifluoromethylthioethers provide high levels of mono-olefination products in good to excellent yields under mild conditions with a 2,2'-bipyridine ligand or AgBF4 as an additive. Mechanistic studies indicate the C-H cleavage is the rate-determining step. The directing group ability of the -SCF3 group is benchmarked against several other weak directing groups by competition experiments under Ir(III)-catalyzed conditions.
The nudeophilic trifluoromethylthiolation of benzyl bromides using (bpy)Cu(SCF3) gave the desired products of benzyl trifluoromethyl sulfides in good to excellent yields. A diverse set of important functional groups including cyano, nitro, ester, alkoxy, halide, and heterocyclic groups can be well tolerated in the protocol. (C) 2013 Elsevier Ltd. All rights reserved.
Ir(III)-Catalyzed Mono-Olefination of Aryl C–H Bonds Using −SCF<sub>3</sub> as a Weak Directing Group
作者:Rui-Peng Bao、Xian Chen、Chen Li、Dong-Hui Wang
DOI:10.1021/acs.orglett.9b03125
日期:2019.10.4
The trifluoromethylthionyl group (-SCF3) is an efficient weak directing group for Ir(III)-catalyzed aryl C-H olefination. Various trifluoromethylthioethers provide high levels of mono-olefination products in good to excellent yields under mild conditions with a 2,2'-bipyridine ligand or AgBF4 as an additive. Mechanistic studies indicate the C-H cleavage is the rate-determining step. The directing group ability of the -SCF3 group is benchmarked against several other weak directing groups by competition experiments under Ir(III)-catalyzed conditions.