Water → N-(2-aminobenzothiazol-6-yl)-4-trifluoromethoxybenzamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 6-aminobenzothiazol-2-yl tert-butyl carbamate (Intermediate 4, 0.900 g, 3.39 mmol) in pyridine (8 mL), 4-trifluoromethoxybenzoyl chloride (0.535 mL, 3.39 mmol) was added. After stirring for 2 h at 60° C., the solution was poured into water (100 mL). The resulting precipitate was filtered off, washed with water and dried. The so obtained solid was dissolved in dichloromethane (20 mL) and trifluoroacetic acid (20 mL) was added. After stirring for 3 h at r.t., the volatiles were removed in vacuo and dimethyl-formamide (100 mL) was added to the residue. The solution was neutralised by adding saturated sodium hydrogencarbonate solution. Water (400 mL) was added and the mixture was stirred overnight. The precipitated N-(2-aminobenzothiazol-6-yl)-4-trifluoromethoxy-benzamide was filtered off, washed with water and dried (grey solid, 1.16 g, 3.27 mmol, 84%). LC/ESI-MS: m/z=354 [M+H]+; m/z=352 [M−H]−; Rt=3.20 min.

Provenance & Evidence