To improve a widely and generally usable method for cross coupling a carbon electrophile and a carbon nucleophile by using a catalyst, which method forms in-situ the carbon nucleophile by removing a carboxyl group from a metal carboxylate.

This method includes forming a carbon-carbon bonding by reacting a carboxylate and a carbon electrophile while decarboxylating them in the presence of a catalyst of a transition metal or transition metal compound. Also there is provided such a catalytic system for a carbon-carbon bonding involving a decarboxylation, namely a carbon-carbon bonding of a carboxylate and a carbon electrophile, as includes a palladium compound, a copper compound, and a chelatable cyclic amine or a substituted compound thereof selected from the group consisting of phenanthroline, dipyridine, and terpyridine.