Synthesis
A. To a reaction vessel was added 0.23 mol of 2-(4-chloro-3-nitrobenzoyl)benzoic acid, 300 mL of a 35% by mass sodium nitrate solution and 500 mL of a 24% by mass potassium carbonate solution. The temperature of the solution was raised to 60 °C, followed by the addition of 1.31 g of chlorobenzoic acid solution, 0.311 g of cuprous chloride and 0.211 g of potassium iodide. The stirring speed was controlled to 160 rpm and the temperature of the solution was raised to 70 °C and refluxed for 3 hours.
B. The reaction solution was cooled to 20 °C and filtered. The filter cake was washed with sodium bisulfite solution with a mass fraction of 52%, then the temperature of the washed solution was raised to 50 °C, 300 mL of ammonium chloride solution with a mass fraction of 37% was added, and stirred for 90 minutes.
C. The solution was cooled to 10 °C and filtered by pumping. The filter cake was washed with potassium bromide solution and subsequently dehydrated with anhydrous magnesium sulfate as dehydrating agent to finally obtain 2-(3-amino-4-chlorobenzoyl)benzoic acid (60.30 g, 95% yield).
References
[1] Russian Journal of Organic Chemistry, 2001, vol. 37, # 5, p. 673 - 676
[2] Patent: CN105906521, 2016, A. Location in patent: Paragraph 0019; 0020; 0021; 0022; 0023
[3] Angewandte Chemie - International Edition, 1999, vol. 38, # 18, p. 2777 - 2779
[4] Patent: DE148110,
[5] Journal of Medicinal Chemistry, 1965, vol. 8, p. 691 - 694
