Cu^II-Catalyzed cis-Selective Synthesis of Ketoepoxides from Phenacyl Bromides and Water

A verityof & alpha;,& beta;-ketoepoxides was synthesizedusinga Cu-II-catalyzed oxidative C-C/O-C coupledcyclization strategy with high yield and cis-selectivity. Water isused as the source of oxygen and phenacyl bromide as the carbon inthe valuable epoxides. The self-coupling method was extended to cross-couplingbetween phenacyl bromides with benzyl bromides. A high cis-diastereoselectivitywas observed in all the synthesized ketoepoxides. Control experimentsand density functional theory (DFT) study were performed to understandthe Cu-II-Cu-I transition mechanism.