Synthesis of 2-Arylquinazolin-4(3H)-ones by N-Aryl Benzamidines with Aromatic Carbonates

摘要

The reaction of N-aryl benzamidines 1a–n with diphenyl carbonate 2a or ethyl phenyl carbonate 2b synthesized 2-arylquinazolin-4(3H)-ones 3a–n in simple and safe process with good yields (71–90%). It was suggested that different electron-donating substituent in N-aryl benzamidines 1a–n afforded similar effect to the yields of 2-arylquinazolin-4(3H)-ones 3a–n. In these reactions, N-aryl benzamidines 1a–n built up intermediate compounds by nucleophilic addition to carbonates 2 to give annulation products 3a–n, following to cyclization involving the elimination of ethanol/phenol.