Pyridine → 1-Bromo-3-fluorobenzyl bromide

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-bromo-3-fluorobenzyl alcohol (1.61 kg, 7.85 mol) in chloroform (14 L) at 0° C. add pyridine (770 mL, 9.52 mol) in one portion (slight exotherm) and stir at 0° C. for 5 min. Add phosphorus tribromide (900 mL, 9.49) dropwise while maintaining the internal temperature below 20° C. and stir the resulting solution overnight while allowing to warm to room temperature. Cool the reaction to 0° C. and quench slowly with ice water (2 L). Transfer to a 50 L flask, separate the layers and then extract the aqueous layer with chloroform (1 L). Wash the combined organic phases with 5% sulfuric acid (2 L), saturated aqueous sodium bicarbonate (2 L), brine (2 L), dry over magnesium sulfate, filter, and concentrate to obtain the title compound as a yellow oil (1753 g, 83%). 1H NMR (CDCl3) δ 7.43 (d, 1H), 7.21 (m, 1H), 7.09 (t, 1H), 4.68 (s, 2H).

Provenance & Evidence