A facile and general method for copper-catalyzeddecarboxylative alkylcarboxylation of cinnamic acids with dimethyl 2,2′-azobis(2-methylpropionate) has been developed. The scope and versatility of the reaction was demonstrated, and a broad range of substrates bearing electron-donating and -withdrawing groups on the aromatic rings were all compatible with this reaction to provide desired β,γ-unsaturated