1-Aryl-5-methoxypyrrolones as synthons for fused heterocycles

3-Di(methylsulfonyl)methylene-pyrrol-2-one and 2-(1-aryl-5-methoxy-2-oxo-2,3-dihydro-1H-3-pyrrolylidene)malononitrile were obtained from 1-aryl-5-methoxypyrrolones. Aziridine and hydroxylamine reacted with pyrrol-2-one to afford 2,7-diazaspiro[4.4]nona-3,6-diene and oxime derivatives, respectively. Pyrrolo[2,3-c]isoxazoles or pyrrolo[2,3-c]isothiazole were formed in high yield from oximes depending upon the reaction conditions employed for ring closure. Treatment of pyrrolylidene malononitrile with N1,N2-di(4-chlorophenyl)acetamidine in ethyl acetate furnished azepine derivatives in 70–75% yield.