Inside-out core-shell architecture: controllable fabrication of Cu2O@Cu with high activity for the Sonogashira coupling reaction.

Inside-out core-shell architectures (Cu(2)O@Cu) with a Cu(2)O core and a Cu shell, which are in contrast to the normally reported Cu(2)O-outside structure (Cu@Cu(2)O), were fabricated. This strategy can also be applied to construct square and hexapod Cu(2)O@Cu. The obtained Cu(2)O@Cu composite exhibits excellent catalytic activity for the Sonogashira coupling reactions.