Synthesis
General procedure for the synthesis of 4-(chlorodifluoromethoxy)aniline from 1-(chlorodifluoromethoxy)-4-nitrobenzene: 167 g of 1-(chlorodifluoromethoxy)-4-nitrobenzene was added to an autoclave, followed by the addition of 200 g of ethyl acetate and 15 g of nickel Nguyenne. After changing to a nitrogen atmosphere, hydrogen was introduced and the pressure in the autoclave was maintained at 2~3 MPa, and the reaction temperature was controlled at 30-40 °C. After the system pressure was stabilized and no longer decreased, the reaction was continued for 1 hour. Upon completion of the reaction, samples were taken and analyzed to ensure that the residual nitro compounds in the hydrogenation reaction solution were less than 0.5%. Subsequently, the catalyst was removed by filtration, and most of the solvent was firstly recovered by distillation at atmospheric pressure, and then purified by decompression distillation, finally 92.6 g of 4-(chlorodifluoromethoxy)aniline was obtained with a yield of 64.2%.
References
[1] Russian Journal of Organic Chemistry, 2002, vol. 38, # 2, p. 269 - 271
[2] Green Chemistry, 2018, vol. 20, # 1, p. 130 - 135
[3] Patent: CN104119238, 2016, B. Location in patent: Paragraph 0018; 0032; 0033; 0037; 0038
