Bromoacetonitrile → 4-(5-Chloro-2-hydroxy-phenyl)-4-oxo-butyronitrile

A solution of 1-(5-chloro-2-hydroxy-phenyl)-ethanone (1.0 g, 5.86 mmol) and magnesium methylcarbonate (13 mL, 32.5 mmol, 2.5 M solution in DMF) was stirred at 120° C. for 3 hours. The mixture was cooled to ambient temperature followed by the addition of bromoacetonitrile (1.22 mL, 17.6 mmol). The resulting solution was stirred at 90° C. for 3 hours. The reaction was cooled to ambient temperature then slowly poured into 1 M hydrochloric acid (200 mL). This was extracted with ethyl acetate, washed with brine, dried over magnesium sulfate, filtered and concentrated. Flash chromatography on silica gel gave the title compound (0.72 g).