Cu-catalyzed carboboration of acetylene with Michael acceptors.

A copper-catalyzed three-component carboboration of acetylene with B 2 Pin 2 and Michael acceptors is reported. In this reaction, a cheap and abundant C2 chemical feedstock, acetylene, was used as a starting material to afford cis -alkenyl boronates bearing a homoallylic carbonyl group. The reaction was robust and could be reliably performed on the molar scale. Furthermore, the resulting cis -alkenyl boronates could be converted to diverse functionalized molecules with ease.