Application
2-Methyl-5-aminophenol is a well-known intermediate among many phenol derivatives. Due to its good biological activity, it is often used as an important raw material or intermediate in the synthesis of pharmaceuticals and pesticides, playing an important role in the synthesis of phenolic drugs.
Chemical Properties
Beige crystals
Uses
The spectrophotometric course of the reaction of 5-amino-2-methylphenol with
p-benzoquinone di-imine was studied
.
General Description
Brown powder.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
5-Amino-o-cresol reacts with strong oxidizing agents.
Fire Hazard
Flash point data are not available for 5-Amino-o-cresol, but 5-Amino-o-cresol is probably combustible.
Flammability and Explosibility
Not classified
Synthesis
General procedure for the synthesis of 2-methyl-5-aminophenol from 3-chloro-4-methylaniline: 1700 kg of 50% sodium hydroxide solution was added to a 4800 L autoclave, followed by 1850 kg of ethanol solution containing 1000 kg of 3-chloro-4-methylaniline. Then 50kg of cuprous chloride and 15kg of copper powder were added as catalyst. The reaction vessel was sealed and replaced with nitrogen five times to ensure an oxygen-free environment. The reaction mixture was heated to 175°C and maintained at this temperature for 4 hours, during which time it was sampled and analyzed to monitor the progress of the reaction. Upon completion of the reaction, the mixture was cooled to room temperature. Ethanol was recovered under reduced pressure and then the reaction mixture was filtered and transferred to an 8000 L tank. The pH was adjusted to weak acidity by adding 1450 kg of industrial hydrochloric acid to the filtrate. Extraction was carried out with 2000L of ethyl acetate for three times. The organic phases were combined and the ethyl acetate was recovered by distillation under reduced pressure to obtain the crude product. To the crude product, 1000kg of ethanol was added, heated to 60°C to dissolve, and then 50kg of activated carbon was added to decolorize. After stirring for 1 hour, the activated carbon was removed by hot filtration and the filtrate was cooled to 5°C for crystallization. Finally, 707kg of 2-methyl-5-aminophenol was obtained with a yield of 85.36% and a purity of 99.8%.
References
[1] Patent: CN107963974, 2018, A. Location in patent: Paragraph 0030-0032; 0036; 0037
