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Abstract This work describes reaction of Pyrazols 3a-d with 2a-d in sodium ethoxide to afford one of the two expected products namely 2,7-diamino-3-arylazo-pyrazolo[1,5-a]pyrimidines 6a-g or its isomer 2,5-diamino -3-arylazo-pyrazolo[1,5-a]pyrimidines 7a-g .Through intermediacy structure of 4a-g and 5a-g, the structure of 6a-g was confirmed by elemental analysis, spectral data [IR, Mass and H1 NMR ] .The reaction seemed to proceed via the intial elimination of ethyl alcohol by the exocyclic amino group, followed by cyclization through Michael addition reaction since NH group of pyrazole added to cyano group and cyclization occurred leading formation of the product 6a-g (fig 1). In an extension of this work the present papers describe a new synthesis of N-aryl-2-pyridone 10a-j by the reaction of compound 2a-d with active methylene compound 8a-c in sodium ethoxide solution, The structures of the reaction products 10a-j were established and confirmed by their elemental analysis and spectral data (MS, IR, and 1H NMR). The formation of 10a-j from 2 and 8 is assumed to proceed via intermediacy of 9, which were cyclized to the final N-aryl-2-pyridone derivatives 10 a-j (fig 2). |