Abstract Hydrozirconation reaction of alkynylsilanes 1 followed by Michael addition to α, β- unsaturated ketones in the presence of CuBr· Me 2 S complex produced (Z)-γ-silyl-γ, δ- unsaturated ketones 3 stereoselectively. 1, 4-Diketones were prepared via epoxidation and hydrolysis of 3.