Utilization of 2-Ylidene-4-thiazolidinones in Synthesis of Heterocyclic Compounds Part (II): Transformation of (4-Oxo-3-phenyl-1,3-thiazolidin-2-ylidene)malononitrile to 3-Aminothiophene Derivatives

摘要

Alkyl 3-aminothiophene carboxylates derivatives (3a-d) were prepared via reaction of (4-oxo-3-phenyl-1,3-thiazolidin-2-yhdene)malononitrile (2) with alcohols. Compound 3a was allowed to react with acetic anhydride, chloroacetyl chloride and nitrous acid to afford N,N,N-triacetylthiophene, 3-chloro-acetamidothiophene and 3-diazothiophene derivatives (6,7 and 8), respectively. Compound 8 was allowed to react with sodium azide to afford the 3-azidothiophene derivative (9). On the other hand, 3-amino-2-carboxamidothiophene derivatives (10a-c) were prepared via reaction of compound 2 with a variety of amines. Compound 10a was allowed to react with acetic anhydride to afford thieno[3,2d]oxazinone (12).