Carbon tetrabromide → 4-Bromo-1-(bromomethyl)-2-methylbenzene

Participants

Reaction Conditions

Reaction Steps

(4-Bromo-2-methylphenyl)methanol (10.4 g, 51.6 mmol) is dissolved in anhydrous CH2Cl2 (150 mL) and CBr4 (18.8 g, 56.8 mmol) added. The reaction mixture is cooled to 0-5° C. and PPh3 (14.9 g, 56.8 mmol) is added. The reaction mixture is stirred overnight then hexane/EtOAc (9:1) (250 mL) is added with vigorous stirring. The triphenylphosphine oxide that forms during the reaction is filtered off and the filtrates are concentrated in vacuo. The resulting oil is purified on a silica gel pad with hexane/EtOAc (8:2). The solvent are removed on a rotary evaporator and the bromoform is removed by vacuum distillation (15 mm Hg, bp: 40-50° C.) to provide the expected product 1-Bromo-4-(bromomethyl)-3-methylbenzene (13.23 g, 97%) as a yellow oil. 1H NMR (300 MHz, CHLOROFORM-D): δ 7.37-7.27 (2H, m), 7.17 (1H, d, J=8.1 Hz), 4.45 (2H, s), 2.39 (3H, s).

Provenance & Evidence