Reactions of some benzofuran derivatives with amides,nitriles and hydrazines

When 6-acetoacetyl-5-methoxy- ( 1b ) and 5-acetoacetyl-6-methoxy-2,3-diphenylbenzofuran ( 2b ) were treated with cyanoacetamide, the corresponding pyridinecarbonitriles were obtained. Compounds 1b and 2b reacted with ethyl cyanoacetate in the presence of ammonium acetate to give the benzofuranyl-pyrone derivatives. This reaction, when carried out in presence of diethylamine, led to the formation of furochromones. Hydrazine hydrate, phenylhydrazine and semicarbazide hydrochloride reacted with 1b and 2b with the formation of the corresponding pyrazoles. The corresponding isoxazole derivatives were formed by the reaction of 1b and 2b with hydroxylamine hydrochloride.