Hydrochloric Acid → 2,4-Dibromobenzonitrile

Temperature

45 °C

A solution of copper(I) cyanide (2.32 g, 25.9 mmol) in anhydrous dimethylsulfoxide (50 mL) is stirred at 60° C., and to this solution is added tert-butylnitrite (7.1 mL, 59.7 mmol) all at once. A solution of 2,4-dibromoaniline (5.0 g, 19.9 mmol) in anhydrous dimethylsulfoxide (30 mL) is added dropwise, via cannula, to the mixture. After the addition is complete the reaction mixture is stirred for 1 hr, cooled to 45° C., and then treated slowly with 5N HCl (50 mL). Five minutes later, the reaction mixture is cooled to ambient temperature and extracted with 1:1 ethyl acetate:hexane (2×300 mL). The combined organic layers are washed with water (100 mL) and saturated aqueous sodium chloride (100 mL), dried, concentrated under reduced pressure and the residue subjected to silica gel chromatography, eluting with hexane containing from 0–5% ethyl acetate. Fractions containing product are combined and concentrated under reduced pressure to provide the title compound (1.61 g, 31% yield).

1. additionAfter the addition
2. temperatureFive minutes later, the reaction mixture is cooled to ambient temperature
3. extractionextracted with 1:1 ethyl acetate
4. washThe combined organic layers are washed with water (100 mL) and saturated aqueous sodium chloride (100 mL)
5. customdried
6. concentrationconcentrated under reduced pressure
7. washeluting with hexane containing from 0–5% ethyl acetate
8. additionFractions containing product
9. concentrationconcentrated under reduced pressure

ORD record

ord-5cf74bb57cac43d5aa914d918d27dd6f

Source dataset

uspto-grants-2007_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07183320B2