Conjugate Addition of Phosphine-Complexed Organocopper Reagents to α,β-Unsaturated Ketones

Organocopper reagents formed from equimolar amounts of copper(I) iodide and organolithiums and 2 to 3 equiv of tri-n-butylphosphine undergo smooth reaction with α,β-unsaturated ketones, and after aqueous quenching afford β-substituted ketones in high yields. This method is economical (enone/organolithium=1:1.05 to 1:1.25) and applicable to a wide variety of entering groups and enone substrates, and compares well with the existing procedures.