Diethyl Ether → 2-Bromo-5-hydroxybenzonitrile

Temperature

19 °C

To a stirred solution of 3-cyanophenol (2.00 g, 18.0 mmol) in anhydrous acetonitrile (20 mL) under N2 at −30° C. was added dropwise 54% HBF4.Et2O (2.48 mL, 18.0 mmol). The temperature was maintained below −20° C. during addition. To this stirred solution was added NBS (3.27 g, 18.0 mmol) portion wise keeping the temperature below −10° C. After the addition was complete, the solution was allowed to warm to 19° C. The reaction mixture was diluted with 38% NaHSO3 (10 mL) and extracted with MTBE (2×25 mL). The organic layer was washed with H2O (2×25 mL) and brine (25 mL), dried (MgSO4), filtered, and concentrated to give a white solid (3.15 g). Purification of a portion of this product (1.0 g) by radial chromatography (30% EtOAc/hexane) gave 0.51 g of the title compound as a white solid. mp 183-184° C. Anal. Calculated for C7H4BrNO: C, 42.46; H, 2.04; N, 7.07. Found: C, 42.44; H, 1.93; N, 6.90.

1. temperatureThe temperature was maintained below −20° C. during addition
2. customthe temperature below −10° C
3. additionAfter the addition
4. extractionextracted with MTBE (2×25 mL)
5. washThe organic layer was washed with H2O (2×25 mL) and brine (25 mL)
6. dry with materialdried (MgSO4)
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-86dfb30e73e34b0cb6c6cfa48d4d99c2

Source dataset

uspto-grants-2007_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07282501B2