Hydrochloric Acid → 2-[(2,1,3-Benzothiadiazol-4-ylsulfonyl)amino]-5-chlorobenzoic acid

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Reaction Steps

LiOH.H2O (0.68 g, 16.2 mmol) was added to a stirred solution of 2-(benzo[1,2,5]thiadiazole-4-sulfonylamino)-5-chloro-benzoic acid methyl ester (1.56 g, 4.06 mmol) in THF (15 mL) and water (5 mL). After 18 h, the solution was acidified to pH 2 with conc. HCl, diluted with water, and extracted with DCM (3×). The combined organic layers were dried (MgSO4), and concentrated to provide the title compound (1.50 g, 100%). HPLC: RT=9.48 min. MS (ESI−): mass calcd. for C13H8ClN3O4S2, 368.96; m/z found, 368/370 [M−H]. 1H NMR (500 MHz, CDCl3): 11.07 (s, 1H), 8.38 (dd, J=7.0, 1.0, 1H), 8.24 (dd, J=8.8, 1.0, 1H), 7.92 (d, J=2.5, 1H), 7.75 (d, J=9.0, 1H), 7.71-7.69 (m, 1H), 7.40 (dd, J=9.0, 2.6, 1H).

Provenance & Evidence