反应详情

6-Amino-1H-indazole-7-carboxylic acid methyl ester (formula 14, obtained according to Example IV) (1.35 g, 7.0 m-mol) was heated with formamide (4.2 ml) at 140° for a period of 4 hours and again at 180° for a period of 1.5 hours. The product that formed on cooling was collected and washed with a small amount of cold water to yield 555 mg of the formula 2 target compound. Additional amounts of the target compound were obtained by working-up the mother liquor. The cumulative product yield was 965 mg (74%), m.p. 325°-327° (decomp.); ir (KBr): 1570, 1620, 1685 cm-1 (aromatic, C=C, C=N, CO); pmr (DMSO-d6): δ 7.45 and 8.22 (2 d, 2, J=9 Hz, H4 and H5), 8.30 and 8.32 (2s, 2, H3 and H7), 13.44 (broad m, 2, D2O-exchangeable N1 --H and N8 --H); ms (70 eV): m/e 186 (100%, M+), 158 (16%, M+--CO).

1. customThe product that formed
2. temperatureon cooling
3. customwas collected
4. washwashed with a small amount of cold water