945557-04-0

573675-27-1

945557-04-0

The general procedure for the synthesis of 5-bromo-3-chloro-2-pyridinecarbonitrile from 3-amino-5-bromo-2-pyridinecarbonitrile was as follows: to a suspension of 3-amino-5-bromo-2-cyano pyridine (198 mg, 1.00 mmol) in 37% hydrochloric acid (2.00 ml) and water (0.5 ml) at 0°C, sodium nitrite (83.0 mg, 1.20 mmol) and the reaction was stirred for 1 hour. Subsequently, copper powder (15 mg) was added and the mixture was refluxed for 30 minutes. After completion of the reaction, the mixture was cooled, the reaction was quenched with ice water and alkalized with 5N sodium hydroxide solution. The reaction mixture was extracted with ethyl acetate and the organic phase was washed with brine and dried over anhydrous magnesium sulfate. The crude product was purified by silica gel column chromatography with 0-30% ethyl acetate/hexane as eluent to give 110 mg of 5-bromo-2-cyano-3-chloropyridine in 50% yield.