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

A solution of Intermediate 62 (1.29 g) in chloroform (12 ml) was added dropwise with a solution of bromine (272 μl, WAKO) in chloroform (1.5 ml), refluxed with heating for 2.5 hours and then 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 63, 609 mg).

1. temperaturerefluxed
2. temperaturewith heating for 2.5 hours
3. concentrationThe reaction mixture was concentrated under reduced pressure
4. additionadded with water (50 ml) and methylene chloride (150 ml) for extraction
5. customThe organic layer was dried
6. customthe solvent was evaporated under reduced pressure
7. customThe residue was purified by column chromatography (Quad, hexane:ethyl acetate=2:1)

ORD record

ord-7ab3c645bb234779bf09289e3d7e8b0a

Source dataset

uspto-grants-2005_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06867320B2