反应详情

Indazole (3.5 g, 29.6 mmol) and acetic anhydride (35 ml) were heated at 60° C. under nitrogen for 3 h. Excess acetic anhydride was evaporated and the remaining oily residue partitioned between 3% aqueous NaHCO3 (20 ml) and EtOAc (30 ml). The organic layer was separated, dried (MgSO4) and evaporated to provide the title product (4.5 g, 96%); 1HNMR (400 MHz, CDCl3) δ: 2.80 (s, 3H), 7.37 (t, 1H), 7.58 (t, 1H), 7.75 (d, 1H), 8.46 (d, 1H).

1. customExcess acetic anhydride was evaporated
2. customthe remaining oily residue partitioned between 3% aqueous NaHCO3 (20 ml) and EtOAc (30 ml)
3. customThe organic layer was separated
4. dry with materialdried (MgSO4)
5. customevaporated