THE REACTION OF METHYL -AMINO-4-CYANO-5-METHYLTHIOTHIOPHENE-2-CARBOXYLATE WITH DMAD - A NEW SYNTHESIS OF POLYFUNCTIONALIZED QUINOLINES

The reaction of methyl -amino-4-cyano-5-methylthiothiophene-2-carboxyl ate (2), which was prepared by the reaction of bis(methylthio)methylen epropanedinitrile (1) with methyl thioglycolate followed by dimethyl a cetylenedicarboxylate (DMAD) in the presence of potassium carbonate in dimethyl sulfoxide gave the polyfunctionalized quinoline, pentamethyl ino-5-mercaptoquinoline-2,3,6,7,8-pentacarboxylate (3). The oxidation of 3 with iodine in DMSO provided the novel ring system in the form o f the derivative, pentamethyl zolo[3,4,5-de]quinoline-3,4,6,7,8-pentac arboxylate (4).