3-Chloro-2-methylaniline
[CAS# 87-60-5]

Identification

• Classification: Biochemical >> Carbohydrate >> Monosaccharide
• Name: 3-Chloro-2-methylaniline
• Synonyms: 3-Chloro-o-toluidine; 3-chloro-o-toluidine; Azoic Diazo Component 46; Fast Scarlet TR Base; 3-Chloro-2-Methylbenzenamine
• Molecular Formula: C₇H₈ClN
• Molecular Weight: 141.60
• CAS Registry Number: 87-60-5
• EC Number: 201-756-6
• SMILES: CC1=C(C=CC=C1Cl)N

Properties

• Density: 1.171
• Melting point: 2-3 °C
• Boiling point: 115-117 °C
• Refractive index: 1.588-1.59
• Flash point: 112.8 °C

Safety Data

• Hazard Symbols: GHS05;GHS06;GHS07;GHS08;GHS09 Danger
• Risk Statements: H301-H311-H314-H317-H318-H334-H373-H411
• Safety Statements: P233-P260-P261-P262-P264-P264+P265-P270-P271-P272-P273-P280-P284-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P319-P321-P330-P333+P317-P342+P316-P361+P364-P362+P364-P363-P391-P403-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	3	H311
Skin sensitization	Skin Sens.	1B	H317
Serious eye damage	Eye Dam.	1	H318
Skin corrosion	Skin Corr.	1B	H314
Respiratory sensitization	Resp. Sens.	1	H334
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Specific target organ toxicity - single exposure	STOT SE	3	H335
Specific target organ toxicity - repeated exposure	STOT RE	1	H372
Specific target organ toxicity - single exposure	STOT SE	1	H370

• Transport Information: UN 2239

Discovery and Applications

3-Chloro-2-methylaniline, also known as 2-amino-3-chlorotoluene, is an aromatic amine with the chemical formula C7H8ClN. Structurally, it consists of a benzene ring substituted with an amino group (–NH2) at the 2-position, a methyl group (–CH3) at the 3-position, and a chlorine atom at the adjacent 4-position. This chemical has gained significance due to its reactivity and utility as an intermediate in the synthesis of various organic compounds, including pharmaceuticals, agrochemicals, and dyes.

The discovery of 3-chloro-2-methylaniline was largely driven by the need for versatile building blocks in the development of aromatic compounds. It can be synthesized by the chlorination of 2-methylaniline, a process that introduces the chlorine atom into the aromatic ring. Chlorination is typically achieved using reagents like thionyl chloride (SOCl2) or chlorine gas (Cl2), under controlled conditions to direct the substitution to the desired position.

One of the primary applications of 3-chloro-2-methylaniline is in the pharmaceutical industry, where it is used as an intermediate in the synthesis of active pharmaceutical ingredients (APIs). The amino, chloro, and methyl groups on the benzene ring make the compound reactive towards various chemical transformations, enabling the formation of complex molecular structures. It has been employed in the development of drugs for treating conditions such as cardiovascular diseases and neurological disorders.

In the agrochemical sector, 3-chloro-2-methylaniline serves as a key intermediate in the production of herbicides and fungicides. Its reactivity allows for the creation of molecules that are effective in controlling weeds and fungal pathogens, contributing to improved crop yields and agricultural productivity.

Additionally, the compound is used in the dye industry for the synthesis of azo dyes and pigments. The presence of both electron-donating (amino) and electron-withdrawing (chloro) groups on the aromatic ring makes it suitable for undergoing diazotization reactions, which are essential in the production of vibrant and stable dyes used in textiles, plastics, and inks.

Despite its utility, 3-chloro-2-methylaniline is classified as a hazardous substance. It can cause skin and eye irritation upon contact, and inhalation of its vapors may lead to respiratory issues. Proper safety protocols are required when handling the compound in industrial and laboratory settings to minimize exposure risks.

In conclusion, 3-chloro-2-methylaniline has become an important chemical in modern organic synthesis. Its discovery and development have expanded the capabilities of pharmaceutical, agrochemical, and dye industries, demonstrating its value as a versatile intermediate.

References

2023. Multimodal action of KRP203 on phosphoinositide kinases in vitro and in cells. Biochemical and Biophysical Research Communications, 680.
DOI: 10.1016/j.bbrc.2023.08.050

2022. A quantitative high-throughput screen identifies compounds that lower expression of the SCA2-and ALS-associated gene ATXN2. The Journal of biological chemistry, 298(8).
DOI: 10.1016/j.jbc.2022.102228

1992. Mineralization of 3-chloro-4-methylaniline via an ortho-cleavage pathway by Pseudomonas cepacia strain CMA1. Applied Microbiology and Biotechnology, 37(6).
DOI: 10.1007/bf00170098