Furan-2-carbaldehyde dimethylhydrazone and maleic anhydride and N-substituted maleimides and fumaronitrile in chloroform at room temperature readily formed nonisolable 1: l cycloadducta which spontaneously lost water, giving 1, 2, 3-trisubstituted benzenes in good yield. With alkynic dienophiles no cycloaddition occurred, and with quinones Michael addition of the furan nucleus to the quinone was the preferred reaction.
