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Part-IISynthesis of PyrimidinesSimilarly, benzofuro[3,2-d]-4-oxopyrimidines 10c have been obtained by the reaction ofthe corresponding, ortho-aminocarboxamide derivative of the benzofuran, with nitriles(Table 23). 45,46NH 2NRO10cONH 2+ RCN dry HCl gasNHOOR = CH 3 , CH 2 Cl, CHCl 2 , etcThe plausible explanation and proof for the reaction mechanism has been discussed indetails in section V in the later part of this review.1.4.2 Synthesis of Condensed 4-ArylpyrimidinesThe hydrogen chloride catalyzed condensation has been found applicable to the synthesisof certain fully aromatic condensed pyrimidines by the reaction of ortho-aminoketoneswith nitriles. Thus, 2-amino-5-chlorobenzophenone 11a has been reacted with aliphaticand aromatic nitriles to obtain the corresponding 2-substituted 4-phenyl-6-chloroquinazolines (Table 28). 23,31OC 6 H 5Cl11aC 6 H 5NH 2+ RCNdry HClClNNRSimilarly, 4-phenylthienopyrimidines have been obtained through the reaction of 2-amino23, 313-benzoylthiophenes 11b with various nitriles.OC 6 H 5C 6 H 5S11bNH 2+RCNdry HCl gasSNNR242