Hydrochloric Acid → 1-(4-Bromo-2-thienyl)ethan-1-one

Temperature

7.5 °C

2-Acetylthiophene (21.6 ml, 0.20 mol) was dissolved in 200 ml CHCl3 at 0° C. AlCl3 (40 g, 0.30 mol) was added in small portions at such a rate as to maintain the temperature at 5-10° C. The reaction mixture was then cooled to 0° C. and bromine, Br2 (11.34 ml, 0.22 mol) was added quickly. The reaction mixture was refluxed for two hours, then was allowed to cool and was poured into a mixture of 400 ml ice water and 50 ml concentrated HCl and stirred for 30 minutes. The organic layer was separated, dried over Na2SO4, and concentrated under vacuum. The crude product was distilled under vacuum to yield pure 4-bromo-2-acetylthiophene (27.6 g, 67%). MS (M−H)−: 204.85; 1H NMR (300 MHz, CDCl3) δ7.58 (1H, d, J=1.3 Hz), 7.53 (1H, d, J=1.3 Hz), 2.55 (3H, s).

1. temperatureThe reaction mixture was then cooled to 0° C.
2. temperatureThe reaction mixture was refluxed for two hours
3. temperatureto cool
4. customThe organic layer was separated
5. dry with materialdried over Na2SO4
6. concentrationconcentrated under vacuum
7. distillationThe crude product was distilled under vacuum

ORD record

ord-3d739821529540e6b2bd6dda05eed86a

Source dataset

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06613786B2