Under nitrogen atmosphere, 1,3,5-trimethylbenzene (0.7 mL, 5 mmol) was added to the reaction vial, followed by the sequential addition of acetic acid (2.6 mL) and 33% wt solution of hydrobromic acid acetic acid (3.5 mL). Next, paraformaldehyde (570 mg, 18.8 mmol, 3.7 equiv) was added. The reaction mixture was stirred at 95 °C. After 3 h, the solid was observed to start precipitating. Stirring of the reaction mixture was continued for 9 h, followed by cooling to room temperature. The reaction mixture was poured into ice water and the solid product was collected by filtration and dried. Recrystallization by mixed solvent recrystallization of dichloromethane and petroleum ether afforded the target compound 2,4,6-tribromomethyltrimethylbenzene as white needle-like crystals (1.99 g, 5 mmol, 99% yield).1H NMR (500 MHz, CDCl3) δ 4.61 (s, 6H), 2.50 (s, 9H).13C NMR (126 MHz, CDCl3) δ 137.84, 133.18, 29.93, 15.38.
