2-Bromothiophene → 2,2'-Bithiophene

Participants

Reaction Steps

Gringard reagent 2-thiophenylmanesium bromide was prepared from 60 g of 2-bromothiophene (0.368 mole) and magnesium (9.7 g, 0.404 mole). Magnesium was slowly added to a mixture of 2-bromothiophene (50 g, 0.307 mole), Ni(dppp)Cl2 (1.66 g, 3 mmol) in 150 mL dry ether at 0° C. The mixture was warmed to RT for 20 h before being quenched by diluted HCl. The aqueous layer was extracted with ether and all organic layers were combined. The solvent was evaporated after drying over MgSO4. The crude liquid product was redistilled under reduced pressure to afford 40 g (80%) of a low melting solid of the tilled compound. Mp 32-33° C. 1H-NMR (300 MHz, CDCl3) δ 7.19 (dd, 4H), 7.04 (t, 2H).

Provenance & Evidence