Electrochemical stereoselective synthesis of polysubstituted 1,4-dicarbonyl Z-alkenes via three-component coupling of sulfoxonium ylides and alkynes with water.

The first straightforward strategy for the synthesis of 1,4-dicarbonyl Z-alkenes has been developed via an electrochemical cross-coupling reaction of sulfoxonium ylides and alkynes with water. The metal-free protocol showed an easy-to-handle nature, good functional group tolerance, and high Z-stereoselectivity, which is rare in previous cases. The proposed reaction mechanism was convincingly established by carrying out a series of control experiments, cyclic voltammetry experiments, and density functional theory (DFT) studies.

C-H Fluoroalkylsulfinylation/Intramolecular Rearrangement for Precise Synthesis of Fluoroalkyl Sulfoxides.

An efficient methodology to access various fluoroalkyl sulfoxides bearing ortho/para-functionalized amine scaffolds from arylhydroxylamines is described. The transformation was featured with new electrophilic trifluoromethylthiolated reagents, good functional group tolerance, and late-stage modification of complex bioactive scaffolds, providing a rapid access to prepare numerous trifluoromethyl- and difluoromethyl-substituted sulfoxides. Mechanism studies and density functional theory calculations suggest this reaction goes through a nucleophilic trifluoromethylthiolation of arylhydroxylamine and subsequent internal 2,3-sigmatropic rearrangement involving a sulfur and oxygen transfer process.