The Cu 2 O-catalyzed reaction of α, β-unsaturated isonitrile with active methylene compound is described. Vinyl isocyanide (VIC) and propenyl isocyanide (PPIC) were employed as the isocyanide components. In addition, allyl isocyanide (AIC), which has been known to be rearranged readily to PPIC by Cu 2 O, was also used as a precursor of PPIC. Five types of products were isolated and identified. These products were explained by a scheme ...