Bromine → 5-Bromo-1,3-benzothiazol-2-amine

Participants

Reaction Steps

A solution of Intermediate 74 (1.29 g) in chloroform (12 ml) was added dropwise with a solution of bromine (272 μl, WAKO) in chloroform (1.5 ml), refluxed by heating for 2.5 hours, and stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure, neutralized with 5% aqueous ammonia, and then added with water (50 ml) and methylene chloride (150 ml) for extraction. The organic layer was dried, and then the solvent was evaporated under reduced pressure. The residue was purified by column chromatography (Quad, hexane:ethyl acetate=2:1) to obtain the title compound (Intermediate 75, 609 mg).

Provenance & Evidence