3-Amino-2-chloro-6-methylphenol
[CAS# 84540-50-1]

Identification

• Classification: Chemical reagent >> Organic reagent >> Phenols
• Name: 3-Amino-2-chloro-6-methylphenol
• Synonyms: 2-Methyl-5-amino-6-chlorophenol; 2-Chloro-3-amino-6-methylphenol; 6-Chloro-5-amino-o-cresol; CAOC
• Molecular Formula: C₇H₈ClNO
• Molecular Weight: 157.60
• CAS Registry Number: 84540-50-1
• EC Number: 283-144-9
• SMILES: CC1=C(C(=C(C=C1)N)Cl)O

Properties

• Density: 1.3±0.1 g/cm³ Calc.^*
• Melting point: 80-83 °C (Expl.)
• Boiling point: 262.7±35.0 °C 760 mmHg (Calc.)^*
• Flash point: 112.6±25.9 °C (Calc.)^*
• Index of refraction: 1.63 (Calc.)^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H302-H315-H319-H335-H411
• Safety Statements: P261-P264-P264+P265-P270-P271-P273-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P319-P321-P330-P332+P317-P337+P317-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Eye irritation	Eye Irrit.	2	H319
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	4	H332
Acute hazardous to the aquatic environment	Aquatic Acute	2	H401
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Skin sensitization	Skin Sens.	1	H317
Acute toxicity	Acute Tox.	4	H312
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400

Discovery and Applications

3-Amino-2-chloro-6-methylphenol is an aromatic compound characterized by a benzene ring substituted with an amino group (–NH₂) at the 3-position, a chlorine atom (–Cl) at the 2-position, and a methyl group (–CH₃) at the 6-position, as well as a hydroxyl group (–OH) attached to the phenolic ring. The molecular structure combines electron-donating and electron-withdrawing substituents, influencing the compound’s chemical reactivity and properties.

The synthesis of 3-amino-2-chloro-6-methylphenol typically involves selective substitution reactions on appropriately substituted phenol precursors. Common routes include the chlorination of 3-amino-6-methylphenol or nitration followed by reduction, enabling the introduction of the chlorine and amino functionalities in a regioselective manner. Alternative synthetic strategies may start from chlorinated methylphenol derivatives with subsequent amination steps. The precise control of reaction conditions is essential to obtain the desired substitution pattern without overreaction or isomer formation.

This compound is utilized as an intermediate in the synthesis of dyes, pharmaceuticals, agrochemicals, and specialty chemicals. The presence of the amino and hydroxyl groups provides reactive sites for further functionalization, such as acylation, sulfonation, or coupling reactions, facilitating the preparation of complex molecules. The chloro substituent often serves as a leaving group or modulates electronic properties to influence reaction outcomes.

In dye chemistry, 3-amino-2-chloro-6-methylphenol is valuable for producing azo dyes and other colorants, where its substituents affect hue, stability, and binding properties. The compound’s reactivity also supports its use in medicinal chemistry for developing compounds with biological activity, including antimicrobial and anti-inflammatory agents.

Analytical characterization of 3-amino-2-chloro-6-methylphenol employs nuclear magnetic resonance (NMR) spectroscopy to confirm the positions of substituents on the aromatic ring. Infrared (IR) spectroscopy detects functional groups such as amino, hydroxyl, and chloro substituents. Mass spectrometry (MS) is used to determine molecular weight and fragmentation patterns. Chromatographic methods such as high-performance liquid chromatography (HPLC) are applied for purity assessment.

Safety considerations include handling the compound with care due to potential irritant effects on skin and mucous membranes. Aromatic amines and chlorinated phenols can pose toxicity risks; therefore, use of personal protective equipment, including gloves and eye protection, and working in well-ventilated environments is advised.

In summary, 3-amino-2-chloro-6-methylphenol is a multifunctional aromatic phenol derivative used primarily as an intermediate in dye and pharmaceutical synthesis. Its well-established synthetic routes, combined with diverse reactivity owing to the amino, chloro, methyl, and hydroxyl groups, facilitate its role in producing advanced chemical products. Analytical techniques and safety practices support its effective and responsible use in industrial and research settings.

References

2022. Analytical method development and dermal absorption of 2-amino-5-nitrophenol (2A5NP), a hair dye ingredient under oxidative condition. Toxicological Research, 39(2).
DOI: 10.1007/s43188-022-00159-9

2004. Final Report on the Safety Assessment of 6-Amino-m-Cresol, 6-Amino-o-Cresol, 4-Amino-m-Cresol, 5-Amino-4-Chloro-o-Cresol, 5-Amino-6-Chloro-o-Cresol, and 4-Chloro-2-Aminophenol. International Journal of Toxicology, 23(Suppl. 2).
DOI: 10.1080/10915810490499037

2018. The Chemical and Products Database, a resource for exposure-relevant data on chemicals in consumer products. Scientific Data, 5.
DOI: 10.1038/sdata.2018.125