1,3-Dibromobenzene → 3-(3-Bromophenyl)pyridine

Participants

Reaction Conditions

Reaction Steps

A mixture of 1,3-dibromobenzene (105.0 g, 0.45 mol), diethyl(3-pyridyl)borane (30.0 g, 0.204 mol) and tetrabutylammonium hydroxide (2 ml of a 40 wt % solution in water) in 1,2-dimethoxyethane (200 ml) and sodium carbonate (100 ml of a 2M solution) was degassed with nitrogen for 15 min before addition of tetrakis(triphenylphosphine)palladium(0) (4.5 g, 3.9 mmol). The mixture was heated at 80° C. for 18 h, cooled to room temperature, diluted with ethyl acetate and extracted with 1M hydrochloric acid (4×250 ml). The combined aqueous phases were made basic with solid sodium hydroxide and then extracted with diethyl ether. The organic layer was washed with water, brine, dried over sodium sulphate and concentrated to give a yellow oil. Purification by silica gel chromatography eluting with isohexane on a gradient of diethyl ether (10% to 50%) gave 3-(3-bromophenyl)pyridine (33.5 g, 70%) as a colourless oil. 1H NMR (400 MHz, CDCl3) δH 7.28-7.40 (2H, m), 7.48-7.57 (2H, m), 7.73 (1H, t, J 2), 7.82-7.87 (1H, m), 8.62 (1H, s), 8.80 (1H, s).

Provenance & Evidence