Hydrochloric Acid → 4-Bromobenzo[b]thiophene

Temperature

185 °C

A mixture of 4-bromobenzo[b]thiophene-2-carboxylic acid (21.05 g), copper powder (7.0 g) and quinoline (170 ml) was stirred at 180-190° C. for 1 hour, allowed to cool to ambient temperature and poured into 2M hydrochloric acid (900 ml). Ethyl acetate (500 ml) was added, the mixture was stirred for 15 minutes, then it was filtered through Celite. The aqueous phase was separated and shaken with ethyl acetate (200 ml), then the combined ethyl acetate solutions were washed with water (500 ml) and saturated aqueous sodium chloride solution (500 ml), dried (Na2SO4), and the solvents were removed in vacuo. The residue was purified by flash chromatography over silica using petroleum ether (b.p. 60-80° C.) as eluant. Appropriate fractions were combined and the solvents removed in vacuo to give 4-bromobenzo[b]thiophene (9.55 g) as a colourless oil which was used without further purification.

1. temperatureto cool to ambient temperature
2. stirringthe mixture was stirred for 15 minutes
3. filtrationit was filtered through Celite
4. customThe aqueous phase was separated
5. stirringshaken with ethyl acetate (200 ml)
6. washthe combined ethyl acetate solutions were washed with water (500 ml) and saturated aqueous sodium chloride solution (500 ml)
7. dry with materialdried (Na2SO4)
8. customthe solvents were removed in vacuo
9. customThe residue was purified by flash chromatography over silica
10. customthe solvents removed in vacuo

ORD record

ord-31e3fc62b787439fb51dd428d806c671

Source dataset

uspto-grants-2005_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06900216B2