Acetic Acid → 3,3'-Dibromo-2,2'-bithiophene

Temperature

0 °C

Zn powder (31.7 g, 0.485 mol) was added in portions to a vigorously stirred refluxing mixture of bithiophene (1) (77.9 g, 0.162 mol) in 400 mL of ethanol containing 40 mL of water, 100 mL of glacial acetic acid, and 8 mL of 3 M HCl (aq). After refluxing for 2 h, the mixture was filtered hot and upon cooling to 0° C., yellow crystals were collected by filtration. The crystals were dissolved in diethyl ether, washed three times with 200 mL of water, once with 100 mL of brine, and dried over anhydrous MgSO4. The organic solution was filtered and the solvent was removed by evaporation to give 49.4 g (94% yield) of a light yellow powder. Anal. Calcd. for C8H4Br2S2: C, 29.65; H, 1.24. Found: C, 29.59; H, 1.14; 1H NMR (CDCl3): 7.41 (d, J=5.3 Hz, 2H), 7.09 (d, J=5.3 Hz, 2H) ppm.

1. temperaturerefluxing
2. temperatureAfter refluxing for 2 h
3. filtrationthe mixture was filtered hot
4. filtrationyellow crystals were collected by filtration
5. dissolutionThe crystals were dissolved in diethyl ether
6. washwashed three times with 200 mL of water
7. dry with materialonce with 100 mL of brine, and dried over anhydrous MgSO4
8. filtrationThe organic solution was filtered
9. customthe solvent was removed by evaporation

ORD record

ord-2e3691d9b5c64fdcb9a8967f8a5d03a8

Source dataset

uspto-grants-2014_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08859714B1