785-30-8

6333-15-9

785-30-8

1. 30 g of 4,4'-dinitrobenzanilide obtained in step 1, 150 mL of N,N'-dimethylformamide and 0.8 g of 3 wt% palladium-carbon catalyst were added to an autoclave. The hydrogenation reaction was carried out at a hydrogen pressure of 0.8±0.1 MPa and a temperature of 100±1 °C until the reaction was complete. Upon completion of the reaction, the reaction mixture was filtered and the solvent was evaporated under vacuum to obtain the crude 4,4'-diaminobenzanilide. 2. The crude 4,4'-diaminobenzanilide obtained in step 2 was added to an autoclave with 100 g of n-butanol and 0.96 g of activated carbon, and nitrogen was passed through for three times to ensure that a positive pressure was maintained in the autoclave. Subsequently, the temperature was raised to 135±1 °C and stirred for 20 min. The filtrate was filtered under nitrogen protection, the filtrate was cooled to 25±1 °C, filtered again and dried. Finally, 22.8 g of electronic grade 4,4'-diaminobenzanilide in the form of white crystalline powder was obtained in 96.1% yield and 99.7% purity (HPLC).