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Part-IISynthesis of PyrimidinesYZR 2R 1XOXNH 2H 2 N RSH 2 N RorNHR 2R 1XN NRROorNHRH 2 N RR 1 , R 2 = H, alkyl, aryl, cycloalkyl, aloxy, carboxy, heterocycloalkyl etc;X = HC=CH, NH, S, O, CH=N, N=NH, etc;Y = COOH, COOR 3 , CONH 2 , COR 3 , CHO,CN, etc;Z =OH, NH 2 ;R = alkyl, aryl,aralkyl, etc.R 3 = CH 3 , C 2 H 5 , alkyl, arylHowever, the direct use of a nitrile (RCN) as a reagent to cyclocondense with o-aminocarbonyl substrates to afford condensed pyrimidines has received rather scant attention.There are a few reports 3,4,5 available in the literature on such reactions under basicconditions. The major drawback of these reactions under basic conditions is poor productyields.OHCOOHNH 2+CH 3 CNNaOEtheatNOHNCOOHNH 2+RCNBase, 200 O Csealed tubeNNR1.3 Reactions of Nitriles Under Acidic ConditionsNitriles have played a major role in the synthesis of a variety of open chain andheterocyclic compounds 6 . The polar C≡N group of the nitrile is prone towardselectrophilic attack at the nitrogen and nucleophilic attack at the carbon.The enhanced electrophilicity of nitriles in the presence of halogen acids is known sincelong. The interaction of a nitrile 4, with an acid or its complexation with a Lewis acidresults in the formation of a species 5, with enhanced electrophilicity and therefore, manyof the reactions of nitriles with nucleophilic reagents are acid catalyzed. Halogen acids222