Visible-Light-Activated Nickel Thiolates for C–S Couplings
作者:Guohua Wang、Lei Gao、Yunhui Feng、Luqing Lin
DOI:10.1021/acs.orglett.3c01474
日期:2023.6.16
Thiolates are known as the inhibitors of metal catalysis due to their strong coordination with the metal. Herein, we reported visible-light-induced homolysis of the Ni–S bond to activate the nickel(II) thiolates for the C–S coupling, obviating the use of exogenous photocatalysts and other additives. Various aryl bromides/iodides can efficiently couple with thiols with a wide range of functional groups
Condensation of nitrobenzaldehydes 3 and alpha-[o-(p-methoxybenzylthio)benzoyl] sulfoxide 4 gave alpha-sulfinyl enones 5. Treatment of 5 with formic acid caused cyclization followed by debenzylation to afford 3-(methylsulfinyl)thioflavanones 6. Double-bond formation with elimination of methanesulfenic acid was performed by refluxing 6 in benzene, and, finally, the nitro group of 2-phenyl-4H-1-benzothiopyran-4-one