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Part-IISynthesis of PyrimidinesNNHNNR 112jNH 2+R 2 CNdry HClR 1 28NNHR 2R 1 = C 6 H 5 , R 2 = NH 2R 1 = CH (CH 3 )C 6 H 5 , R 2 = NH 2R 1 = CH (CH 3 )C 6 H 5 , R 2 = CH 31.4.4 Synthesis of Condensed 4-ChloropyrimidinesIn some of the reactions of o-aminonitriles with nitriles in presence of dry hydrogenchloride, interestingly 4-chloropyrimidine IV has been found to be the sole productformed.NCl+ RCNdry HClN12NH 2NIVRFor example, the reaction of chloroacetonitrile and dichloroacetonitrile withanthranilonitrile 12a in presence of excess of dry hydrogen chloride gas has been found toyield 4-chloro-2-chloromethylquinazolines in 85% yield. Surprisingly the expected 4-amino-2-chloromethylquinazoline was found to be totally absent. 29,61 Similarly, thishydrogen chloride catalysed condensation of active nitriles, especially, chloroacetonitrileand dichloroacetonitrile with thiophene o-aminonitriles 12b and furan o-aminonitriles 12chas been found to give the corresponding 2-substituted condensed 4-chloropyrimidinesderivatives in good yields. 29R 1+NRCNdry HClR 2R 1ClNR 2 NH 2XXNR12 R 1 = R 2 = H, X = -CH=CH-; R 1 = R 2 = CH 3, X = S; R = CH 2 Cl, CHCl 2R 1 , R 2 = -(CH 2 ) 4 -, X = S; R = CH 2 Cl, CHCl 2 ;R 1 = R 2 =C 6 H 5 , X = O; R = CH 2 ClInterestingly, when chloroacetonitrile and dichloroacetinitrile are reacted withanthranilonitrile 12a, thiophene o-aminonitriles 12b, furan o-amino nitrile 12c, as well as,3-amino-2-cyanopyridothiophene 12k, in presence of dry HBr gas. The correspondingcondensed 4-bromo-2-substitutedpyrimidine is the sole product. 63251