Triethylamine → N-(4-tert-butylphenyl)-6-(3-chloropyridin-2-yl)-1,2-benzisothiazol-3-amine 1,1-dioxide

Participants

Reaction Conditions

Reaction Steps

A suspension of the product of Example 1B (0.1507 g, 0.51 mmol) in POCl3 (4.0 mL, 42.9 mmol) was stirred at 90° C. for 90 minutes, cooled to room temperature and excess POCl3 was removed under vacuum. The resulting residue was treated with 4-tert-butylaniline (0.1027 g, 0.69 mmol) in tetrahydrofuran (3 mL), followed by the addition of a solution of triethylamine (0.25 mL, 1.79 mmol) in tetrahydrofuran (2 mL), and stirred at room temperature for 16 hours. The reaction mixture was quenched with saturated NaHCO3 (5 mL) and diluted with dichloromethane (5 mL). The isolated aqueous phase was extracted with dichloromethane (2×10 mL). The combined organic fractions were dried (MgSO4), filtered and concentrated. The residue was purified by silica gel column chromatography, eluted with ethyl acetate/dichloromethane to afford the title compound. MS (ESI+) m/z 426 (M+H)+; (ESI−) m/z 424 (M−H)−; 1H NMR (300 MHz, DMSO-d6) δ 1.32 (s, 9H), 7.55 (m, 3H), 7.79 (m, 2H), 8.16 (dd, J=8.3, 1.5 Hz, 1H), 8.22 (d, J=8.1 Hz, 1H), 8.30 (s, 1H), 8.60 (d, J=8.1 Hz, 1H), 8.71 (dd, J=4.7, 1.4 Hz, 1H), 10.94 (s, 1H).

Provenance & Evidence