The general procedure for the synthesis of 7-bromoquinoline-4-carboxylic acid from the compound (CAS:1219834-21-5) was as follows: compound 1 (1 g) was dissolved in 10 mL of nitrobenzene and heated to reflux overnight for decarboxylation reaction. After completion of the reaction, the reaction mixture was concentrated under reduced pressure and the resulting solid was purified by recrystallization from hexane to give the final brown solid product in 67% (570 mg) yield.