Visible-Light-Induced Tandem Radical Brominative Addition/Cyclization of Activated Alkynes with CBr4 for the Synthesis of 3-Bromocoumarins

Base-promoted triple cleavage of CCl2Br: a direct one-pot synthesis of unsymmetrical oxalamide derivatives

We present a novel, eco-friendly and one-pot approach for synthesizing unsymmetrical oxalamides with the aid of dichloroacetamide and amine/amides in the presence of CBr4 in a basic medium. The use of water as a potent supplement for the oxygen atom source and the detailed mechanism have been disclosed. Moreover, the protocol involves triple cleavage of CCl2Br and the formation of new C-O/C-N bonds, with the advantage of achieving selective bromination using CBr4 with good to excellent yield under mild conditions. The method also demonstrates promise for industrial use, as proven by its effective implementation in gram-scale synthesis conducted in a batch process, along with its utilization in a continuous-flow system.

Synthesis of 1,1-Diarylvinylsulfides via Visible-Light-Promoted Cascade Reaction of Alkynoates with Phenyl Disulfides

Without any additives and photocatalysts, the visible-light-promoted radical cascade reaction between alkynoates and phenyl disulfides has been developed at room temperature. Through S-S bond photolysis and homolytic cleavage, addition of a sulfur radical, aryl migration, decarboxylation, and H atom abstraction, the cascade reaction provides an efficient and practical route to trisubstituted 1,1-diarylvinylsulfides with a wide scope of substrates and good to excellent yields.