3-ethyl-4-fluorobenzonitrile

557-20-0

79630-23-2

869299-63-8

3-Bromo-4-fluorobenzonitrile (200 g, 1 mol) and [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane complex (4.08 g, 5 mmol) were used as raw materials, which were dissolved in THF (1.2 L). A 1.0 M solution of diethylzinc hexane (600 mL, 0.6 mol) was slowly added at 40-50 °C, followed by heating the reaction mixture to 50-60 °C and maintaining the reaction for 4-5 hours. Complete reaction of the feedstock was confirmed by TLC monitoring. After completion of the reaction, the mixture was cooled to room temperature and quenched by addition of 5% dilute hydrochloric acid (1 L). The organic and aqueous layers were separated and the organic layer was washed twice with 500 mL of water followed by removal of solvent by concentration under reduced pressure. Hexane (600mL) and activated carbon (20g) were added to the concentrate and refluxed for 0.5 hours. After cooling to room temperature and filtration, activated carbon (10 g) was added to the filtrate and refluxing was repeated for 0.5 h. The filtrate was cooled and filtered. The filtrate was cooled to -50°C to -60°C and filtered to collect the solid. The resulting solid was dried under reduced pressure at 10-20 °C to give 3-ethyl-4-fluorobenzonitrile (112 g, 75% yield) as a white solid.