反应详情

To a stirred solution of sodium bicarbonate (1.67 g, 19.8 mmol) in water (4.65 mL) and ethanol (9.3 mL) was added 7-ethyl-1H-indazole (771 mg, 5.27 mmol) followed by iodine (1.87 g, 7.38 mmol). After 16 h the reaction mixture was quenched with sodium thiosulfate, diluted with ethyl acetate and washed with water. The organic layer was collected and dried (MgSO4). Purification by chromatography (silica, 5-25% ethyl acetate/hexanes) gave 7-ethyl-3-iodo-1H-indazole (690 mg, 2.54 mmol, 48%) as an off-white solid. MS (M+H)+=272.9; 1H NMR (CDCl3) δ: 7.39 (d, J=8.1 Hz, 1H), 7.30 (d, J=7.1 Hz, 1H), 7.22 (t, J=7.1 Hz, 1H), 2.95 (q, J=7.5 Hz, 2H), 1.41 (t, J=7.5 Hz, 3H).

1. customAfter 16 h the reaction mixture was quenched with sodium thiosulfate
2. additiondiluted with ethyl acetate
3. washwashed with water
4. customThe organic layer was collected
5. dry with materialdried (MgSO4)
6. customPurification by chromatography (silica, 5-25% ethyl acetate/hexanes)