1,4-Dibromobenzene → 2-(4-Bromophenyl)pyridine

Participants

Reaction Conditions

Reaction Steps

1,4-Dibromobenzene (5.90 g, 25.0 mmol) was dissolved in anhydrous diethyl ether (40 mL) and flushed with argon before the solution was cooled to −78° C. and n-butyl lithium (2.5M in hexanes, 10.2 mL, 25.6 mmol) was added dropwise at a rate that maintained the temperature below −70° C. The reaction mixture was stirred at this temperature for 30 minutes then 2-fluoropyridine (1.72 mL, 20.0 mmol) was added dropwise and stirring continued at −78° C. for 1 h then the reaction mixture was allowed to warm to room temperature and stirred for 1 h. The reaction mixture was poured onto water (50 mL) and extracted with diethyl ether (3×50 mL). The combined organic layers were washed with 5% HCl (3×200 mL) then the pH of the aqueous phase was adjusted to 10 by the addition of potassium hydroxide and the aqueous phase was extracted with diethyl ether (3×200 mL). The combined organic phase was dried over sodium sulfate, filtered and evaporated to afford the title compound (2.7 g, 58%). 1H NMR (CDCl3, 300 MHz): 8.71-8.66 (m, 1H), 7.91-7.85 (m, 2H), 7.79-7.67 (m, 2H), 7.64-7.57 (m, 2H), 7.28-7.22 (m, 1H).

Provenance & Evidence