Synthesis
The general procedure for the synthesis of 4-bromo-2-nitro-N-acetylaniline from 4-bromo-2-nitroaniline and acetic anhydride was as follows: 4-bromo-2-nitroaniline (30.3 g, 138 mmol) was dissolved in 240 mL of acetic acid, followed by the addition of acetic anhydride (22.44 g, 220.2 mmol). The reaction mixture was heated to 95 °C and maintained at this temperature for 7.5 hours. Upon completion of the reaction, the reaction solution was cooled to room temperature and slowly poured into 600 mL of ice water. After the ice was completely melted, it was extracted with dichloromethane (90 mL x 3). The resulting solid was dissolved in 600 mL of dichloromethane, and all organic phases were combined and dried with anhydrous sodium sulfate. Finally, the target product N-(4-bromo-2-nitrophenyl)acetamide (35.4 g, orange solid) was obtained in 99.1% yield by concentrating the organic phase.
References
[1] Patent: CN108264511, 2018, A. Location in patent: Paragraph 0243; 0246-0249
[2] European Journal of Organic Chemistry, 2009, # 32, p. 5647 - 5652
[3] Patent: US6369232, 2002, B1. Location in patent: Page column 60
[4] Patent: CN107400092, 2017, A. Location in patent: Paragraph 0393; 0396-0399
[5] Journal of the Chemical Society. Perkin Transactions 1, 2001, # 21, p. 2754 - 2756
