3-Bromo-4-chlorobenzonitrile is a pharmaceutical intermediate obtained by bromination of 4-chlorobenzonitrile. 3-Bromo-4-chlorobenzonitrile can be used to prepare 2-(3-cyano-4-(4-cyanophenyl)phenyl)-4-methyl-1,3-seleno-5-carboxylic acid, a compound used for the treatment and/or prevention of hyperuricemia, as well as for treating gout, arthritis, or heart failure caused by hyperuricemia.
General procedure for the synthesis of 3-bromo-4-chlorobenzonitrile from p-chlorobenzonitrile: 5-chlorobenzonitrile (5 g, 3.63 mmol) was added to 100 mL of 70% sulfuric acid solution, and potassium bromate (6.5 g, 5.98 mmol) was added slowly under stirring conditions. After the addition was completed, the reaction was continued with stirring at room temperature for 4 hours. At the end of the reaction, the product was collected by filtration and dried to give a white solid (5.5 g). The product was analyzed by gas chromatography (GC) with 98% purity and 70% yield.
