Hydrogen Bromide → 5-Bromo-2-methylbenzonitrile

Participants

Reaction Conditions

Reaction Steps

Water (13.5 mL), HBr (74%, 14.4 mL) and 5-amino-2-methylbenzonitrile (2.0 g, 15.1 mmol) dissolved in water (24 mL) was added to a flask and heated to 50° C. for 20 min. Then the mixture was cooled to 0˜5° C., and a solution of NaNO2 (1.2 g, 17.4 mmol) in water was added. The reaction mixture was stirred for 10 min at 0˜5° C., then was warmed to 40° C. A solution of CuBr (6.5 g, 45.1 mmol) in water (36 mL) and HBr (7.2 mL) was added to the mixture, and refluxed for 2 h. The mixture was extracted with AcOEt, and the organic layer was washed by saturated NaHCO3 solution and brine, and dried over Na2SO4. The crude product was purified by flask chromatograph (PE:EA=50:1), obtaining 2.3 g of 5-bromo-2-methylbenzonitrile as a white solid (yield: 77%). 1H NMR (400 MHz, CDCl3) δ 7.72 (s, 1H), 7.59 (d, J=8.0 Hz, 1H), 7.19 (d, J=8.0 Hz, 1H), 2.51 (s, 3H).

Provenance & Evidence