Hydrochloric Acid → tert-butyl (5-(2-(4-(N-(1,2,4-thiadiazol-5-yl)sulfamoyl)-2,5-difluorophenoxy)-5-chlorophenyl)benzo[d]isoxazol-3-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl (5-(5-chloro-2-(4-(N-(2,4-dimethoxybenzyl)-N-(1,2,4-thiadiazol-5-yl)sulfamoyl)-2,5-difluorophenoxy)phenyl)benzo[d]isoxazol-3-yl)carbamate (0.150 g, 0.19 mmol) in dichloromethane (2 mL) was added trifluoroacetic acid (0.1 mL) at 0° C. The reaction mixture was stirred for 20 minutes at 0° C. and saturated aqueous sodium bicarbonate (5 mL) was added. The mixture was allowed to warm to ambient temperature, diluted with dichloromethane (50 mL), and acidified to pH 5 with 1 N hydrochloric acid. The organic phase was washed with brine (10 mL), dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was purified by column chromatography, eluting with a 0-100% ethyl acetate in hexanes, followed by a 0-10% gradient of methanol in ethyl acetate, to afford tert-butyl (5-(2-(4-(N-(1,2,4-thiadiazol-5-yl)sulfamoyl)-2,5-difluorophenoxy)-5-chlorophenyl)benzo[d]isoxazol-3-yl)carbamate in 59% yield (0.071 g) as a colorless solid: 1H NMR (300 MHz, DMSO-d6) δ10.52 (s, 1H), 8.27 (s, 1H), 8.24 (d, J=1.5 Hz, 1H), 7.77 (dd, J=8.8, 1.6 Hz, 1H), 7.69 (d, J=8.7 Hz, 1H), 7.67 (dd, J=6.8, 3.3 Hz, 1H), 7.63 (d, J=2.5 Hz, 1H), 7.48 (dd, J=8.8, 2.6 Hz, 1H), 7.22 (d, J=8.9 Hz, 1H), 7.22-7.16 (m, 1H), 1.44 (s, 9H), (NH not observed); MS (ES+) m/z 657.6 (M+23), 659.5 (M+23).

Provenance & Evidence