1-Bromo-3-chloropropane → 1-(1-(3-chloropropyl)-1H-indazol-5-yl)-4-(4-(trifluoromethyl)phenyl)pyridin-2(1H)-one

Participants

Reaction Steps

To a solution of 1-(1H-indazol-5-yl)-4-(4-(trifluoromethyl)phenyl)pyridin-2(1H)-one (278 mg, 0.783 mmol) in DMSO (4.0 mL) was added 3-bromo-1-chloropropane (1.23 g, 7.83 mmol) and Cs2CO3 (765 mg, 2.35 mmol), and the reaction was stirred at ambient temperature for 18 h. The reaction was diluted with H2O (25 mL) and extracted with EtOAc (3×25 mL). The extracts were washed with brine (25 mL), dried over Na2SO4, and concentrated. Flash chromatography (silica gel, CH2Cl2/MeOH, 100:1) yielded 1-(1-(3-chloropropyl)-1H-indazol-5-yl)-4-(4-(trifluoromethyl)phenyl)pyridin-2(1H)-one. To a solution of 1-(1-(3-chloropropyl)-1H-indazol-5-yl)-4-(4-(trifluoromethyl)phenyl)pyridin-2(1H)-one (84 mg, 0.19 mmol) in DMF (1.0 mL) was added K2CO3 (0.13 g, 0.97 mmol), dimethylamine (1.94 mL, 3.88 mmol, 2.0 M in THF) and KI (32 mg, 0.19 mmol), and the reaction was heated to 45° C. for 18 h. The reaction mixture was cooled, diluted with H2O (25 mL) and extracted with EtOAc (3×25 mL). The combined organic extracts were washed with brine (25 mL), dried over Na2SO4, filtered and concentrated. Flash chromatography (Biotage 25+M column, CH2Cl2/MeOH/NH4OH, 50:1:0 to 20:1:0.1) provided the title compound (54 mg, 63%): 1H NMR (500 MHz, CDCl3) δ 8.06 (s, 1H), 7.75-7.70 (m, 5H), 7.60-7.43 (m, 3H), 6.92-6.91 (m, 1H), 6.53-6.51 (m, 1H), 4.49 (t, J=6.8 Hz, 2H), 2.29 (t, J=6.8 Hz, 2H), 2.23 (s, 6H), 2.13-2.08 (m, 2H).

Provenance & Evidence