N-(4-Aminophenyl)-1,4-benzenediamine
[CAS# 537-65-5]

Identification

• Classification: Organic raw materials >> Amino compound >> Cycloalkylamines, aromatic monoamines, aromatic polyamines and derivatives and salts
• Name: N-(4-Aminophenyl)-1,4-benzenediamine
• Synonyms: 4,4'-Iminodianiline
• Molecular Formula: C₁₂H₁₃N₃
• Molecular Weight: 199.25
• CAS Registry Number: 537-65-5
• EC Number: 208-673-4
• SMILES: C1=CC(=CC=C1N)NC2=CC=C(C=C2)N

Properties

• Density: 1.2±0.1 g/cm³ Calc.^*
• Boiling point: 410.7±20.0 °C 760 mmHg (Calc.)^*
• Flash point: 239.2±25.4 °C (Calc.)^*
• Index of refraction: 1.733 (Calc.)^*

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

Discovery and Applications

N-(4-Aminophenyl)-1,4-benzenediamine is an aromatic diamine with the molecular formula C₁₂H₁₃N₃. Structurally, it consists of a 1,4-diaminobenzene (para-phenylenediamine) core in which one of the amino groups is substituted with a 4-aminophenyl group through a nitrogen–carbon bond. This arrangement results in three amino functionalities distributed across two linked aromatic rings, combining high nucleophilicity with rigidity from the aromatic system. The compound is typically a solid at room temperature, exhibiting pale yellow coloration and good solubility in polar organic solvents such as ethanol, dimethylformamide, and acetone, but limited solubility in water.

N-(4-Aminophenyl)-1,4-benzenediamine is primarily used as a building block in polymer synthesis and dye chemistry. Its amino groups can undergo condensation reactions with dianhydrides, diacid chlorides, or aldehydes to form polyimides, polyamides, or Schiff base derivatives. The presence of three amino groups provides multiple sites for crosslinking, allowing the formation of highly functionalized polymers with enhanced mechanical strength, thermal stability, and chemical resistance.

In addition, the compound serves as a precursor for the synthesis of azo and heterocyclic dyes. The aromatic amino groups can be diazotized and coupled to other aromatic compounds, forming conjugated chromophores with diverse optical properties. This makes it valuable in the production of colorants, pigments, and functional dyes for industrial applications.

Synthetically, N-(4-Aminophenyl)-1,4-benzenediamine can be prepared via selective amination of 1,4-diaminobenzene with 4-nitrochlorobenzene, followed by reduction of the nitro group to the amino group. Careful control of reaction conditions ensures selective substitution and minimizes formation of undesired byproducts. The purified compound is typically obtained through recrystallization or chromatographic techniques.

Overall, N-(4-Aminophenyl)-1,4-benzenediamine is a multifunctional aromatic diamine with three reactive amino groups and a rigid bis-phenyl framework. Its combination of nucleophilic sites, structural rigidity, and ability to undergo crosslinking and functionalization makes it a versatile intermediate for high-performance polymers, dyes, and other aromatic amine-based materials.

References

2020. Springer Lexikon Kosmetik und Körperpflege. Springer Lexikon Kosmetik und Körperpflege.
DOI: 10.1007/978-3-662-59127-7_4

2019. Differential pulse voltammetric determination of the carcinogenic diamine 4,4′-oxydianiline by electrochemical preconcentration on a MoS2 based sensor. Microchimica Acta, 186(12).
DOI: 10.1007/s00604-019-3906-7