反应详情

Part A. 3-chloro-4-fluorophenyl hydrazine (5.00 g, 31.14 mol) and 1-(4-iodophenyl)-4-(trifluoroacetyl)-2,3-piperidinedione (12.8 g, 31.14 mmol) were added together with 120 mL of ethanol and 4 mL of hydrochloric acid (12 M). The mixture was stirred at reflux under N2 for overnight. The reaction was cooled down to rt. The solvents were removed, and the residue was dissolved in EtOAc (200 mL) and washed with water (100 mL×2) and brine (50 mL). It was then dried over Na2SO4 and concentrated. The residue was purified via flash chromatography on silica gel using 4:1 hexane:ethylacetate to give 1-(3-chloro-4-fluorophenyl)-6-[4-iodophenyl]-3-(trifluoromethyl)-1,4,5,6-tetrahydro-7H-pyrazolo[3,4-c]pyridine-7-one as a brown solid (12.5 g, 75% yield). LRMS (AP+): 536.1 (M+H)+. 1H NMR (CDCl3) δ 7.72 (d, 2H), 7.67-7.64 (m, 1H), 7.49-7.44 (m, 1H), 7.19 (t, 3H), 7.06 (d, 2H), 4.12 (t, 2H), 3.17 (t, 2H).

1. temperatureat reflux under N2 for overnight
2. customThe solvents were removed
3. dissolutionthe residue was dissolved in EtOAc (200 mL)
4. washwashed with water (100 mL×2) and brine (50 mL)
5. dry with materialIt was then dried over Na2SO4
6. concentrationconcentrated
7. customThe residue was purified via flash chromatography on silica gel using 4:1 hexane