5-Amino-o-cresol

5-Amino-o-cresol Property

Melting point:

160-162 °C(lit.)

Boiling point:

229.26°C (rough estimate)

Density 

1.0877 (rough estimate)

vapor pressure 

0.002Pa at 25℃

refractive index 

1.5380 (estimate)

storage temp. 

Keep in dark place,Inert atmosphere,Room temperature

solubility 

DMSO (Slightly), Methanol (Slightly)

pka

10.36±0.10(Predicted)

form 

Powder

color 

Pale brown

Water Solubility 

4.11g/L at 20℃

BRN 

2802317

InChIKey

DBFYESDCPWWCHN-UHFFFAOYSA-N

LogP

0.53 at 20℃

CAS DataBase Reference

2835-95-2(CAS DataBase Reference)

EPA Substance Registry System

5-Amino-2-methylphenol (2835-95-2)

Safety

Hazard Codes 

Xi,Xn

Risk Statements 

36/37/38-20/21/22

Safety Statements 

26-36-37/39

WGK Germany 

1

RTECS 

SJ6090000

TSCA 

Yes

HS Code 

29222990

Hazardous Substances Data

2835-95-2(Hazardous Substances Data)

Toxicity

bird - domestic,LD50,oral,562mg/kg (562mg/kg),Archives of Environmental Contamination and Toxicology. Vol. 12, Pg. 355, 1983.

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

5-Amino-o-cresol Chemical Properties,Usage,Production

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

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