反应详情

To a stirred solution of methyl 1-acetyl-1H-indazole-5-carboxylate (1.16 g, 5.31 mmol) in methanol (10 mL) is added HCl (10 mL of a 6.0 M aqueous solution). The mixture is stirred at rt overnight. The methanol is removed in vacuo, and the remaining aqueous solution is basified with 30% aqueous NH4OH to pH=8. The resulting precipitate is collected by filtration, washed with water and dried in vacuo to afford 900 mg (96%) of methyl 1H-indazole-5-carboxylate as a light yellow solid: 1H NMR (400 MHz, DMSO-d6) δ 13.4, 8.5, 8.3, 7.9, 7.6, 3.9.

1. customThe methanol is removed in vacuo
2. filtrationThe resulting precipitate is collected by filtration
3. washwashed with water
4. customdried in vacuo