Trifluoroacetic acid → 4-nitrophenyl 7-(N-(thiazol-2-yl)sulfamoyl)-2H-benzo[b][1,4]oxazine-4(3H)-carboxylate

Participants

Reaction Steps

To a solution of 4-nitrophenyl 7-(N-(4-methoxybenzyl)-N-(thiazol-2-yl)sulfamoyl)-2H-benzo[b][1,4]oxazine-4(3H)-carboxylate (0.050 g, 0.086 mmol) in DCM (0.172 ml) was added trifluoroacetic acid (0.165 ml, 2.146 mmol). The reaction was stirred at RT for 15 minutes until complete deprotection. The reaction was concentrated in vacuo and purified via 500-mg SCX column (product eluted cleanly with methanol wash) to yield, after concentration, 4-nitrophenyl 7-(N-(thiazol-2-yl)sulfamoyl)-2H-benzo[b][1,4]oxazine-4(3 H)-carboxylate (0.036 g, 0.078 mmol, 91% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.73 (br. s., 1 H) 8.28-8.38 (m, 2 H) 8.06 (d, J=8.71 Hz, 1 H) 7.55-7.64 (m, 2 H) 7.34 (dd, J=8.75, 2.20 Hz, 1 H) 7.22-7.30 (m, 2 H) 6.83 (d, J=4.60 Hz, 1 H) 4.36-4.48 (m, 2 H) 4.02-4.11 (m, 2 H). m/z (ESI) 462.9 (M+H)+.

Provenance & Evidence