Hydrogen Bromide → 5-Bromo-2-methylbenzonitrile

Temperature

40 °C

Keep the solution of 5-amino-2-methylbenzonitrile (2.0 g, 15.1 mmol) dissolved in water (24 mL) and HBr (74%, 14.4 mL) stirring for 20 min, then the mixture was cooled to 0˜5° C., and the solution of NaNO2 (1.2 g, 17.4 mmol) in water (13.5 mL) 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 it was stirred for 2 h. The mixture was extracted with AcOEt, and the organic layer was washed with saturated NaHCO3 solution, 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, 1 H), 7.59 (d, J=8.0 Hz, 1 H), 7.19 (d, J=8.0 Hz, 1 H), 2.51 (s, 3 H).

1. temperaturethe mixture was cooled to 0˜5° C.
2. stirringwas stirred for 2 h
3. extractionThe mixture was extracted with AcOEt
4. washthe organic layer was washed with saturated NaHCO3 solution, brine
5. dry with materialdried over Na2SO4
6. customThe crude product was purified by flask chromatograph (PE:EA=50:1)

ORD record

ord-c5764757e1854e49b52d1943cee3ec50

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08067408B2