To a 10 mL glass tube aryl halide (1 mmol), K4FeCN6 (0.6 mmol,220 mg), K2CO3 (1.5 mmol, 207 mg), catalyst (10 mg), and 2 mL DMF were added and the mixture was stirred for appropriate reaction time at 120 ℃ under argon atmosphere. The progress of the reaction was monitored by GC analysis. After completion of the reaction, the reaction mixture was washed with 5 mL water, and the crude product was isolated using dichloromethane (5× 1 mL). Organic extracts were combined, evaporated, and purified by flash chromatography using hexane/EtOAc to give 4-Bromobenzonitrile.