Synthesis
In a 1000 mL autoclave, 100 g of 2,4-dinitrophenol, 405 mL of methanol, and 6 g of Pd/C catalyst were sequentially added, and the mixture was stirred at room temperature for 5 min, followed by system displacement with nitrogen. After ensuring that the autoclave was well sealed, the temperature was gradually increased to 65 °C, while the hydrogen inlet valve was opened to maintain the reaction system pressure at 0.48 MPa, and the reaction lasted for 1 hour. Subsequently, the hydrogen inlet valve was adjusted to increase the pressure to 0.85 MPa, and the reaction was continued for 0.5 hours. Upon completion of the reaction, the system temperature was lowered to 40°C and replaced three times with nitrogen to remove residual hydrogen. The reaction mixture was separated by filtration to recover the Pd/C catalyst, and the filtrate was treated under nitrogen protection to give 64.8 g of 2,4-diaminophenol in 96.16% yield and 99.2% purity.
References
[1] Synthetic Communications, 2006, vol. 36, # 18, p. 2699 - 2704
[2] Applied Organometallic Chemistry, 2017, vol. 31, # 12,
[3] Patent: CN108440333, 2018, A. Location in patent: Paragraph 0037-0046
[4] Synthetic Communications, 2003, vol. 33, # 2, p. 281 - 289
[5] Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2009, vol. 48, # 9, p. 1315 - 1318
