4-Aminophenol hydrochloride
Chemical Additives 2025-03-19
4-Aminophenol hydrochloride is an organic compound with the chemical formula C₆H₈ClNO. It consists of a phenol ring with an amino group (-NH₂) at the 4-position and a hydrochloride salt (-HCl) attached to the amino group. This structure makes it a water-soluble derivative of 4-aminophenol, combining the properties of phenols and amines.
Product Overview
4-Aminophenol hydrochloride (CAS 51-78-5) is an organic compound widely used as an intermediate in pharmaceutical synthesis, particularly in the production of analgesics and dyes. It is a white to light brown crystalline powder with good solubility in water and polar solvents.
Basic Physicochemical Properties
| Property | Specification | Test Method |
|---|---|---|
| Chemical Name | 4-Aminophenol hydrochloride | IUPAC nomenclature |
| Molecular Formula | C₆H₈ClNO | Elemental analysis |
| Molecular Weight | 145.59 g/mol | Mass spectrometry |
| Appearance | White to light brown crystalline powder | Visual inspection |
| Solubility (20°C) | Soluble in water (>100 mg/mL), ethanol, methanol | USP <911> |
| Melting Point | 280-284°C (decomposes) | DSC/TGA analysis |
Key Applications
| Industry | Primary Use | Function |
|---|---|---|
| Pharmaceuticals | Intermediate for paracetamol synthesis | Precursor for APIs |
| Dye Manufacturing | Coupling agent for azo dyes | Color development |
| Photographic Chemicals | Developer in black-and-white films | Reducing agent |
| Rubber Industry | Antioxidant and stabilizer | Prevents degradation |
| Organic Synthesis | Building block for fine chemicals | Multifunctional intermediate |
Quality Specifications
| Parameter | Acceptance Criteria | Test Method |
|---|---|---|
| Purity (HPLC) | ≥98.0% | USP <621> |
| Loss on Drying | ≤0.5% | USP <731> |
| Heavy Metals (Pb) | ≤10 ppm | ICP-MS |
| Residual Solvents | Meets ICH Q3C Class 3 limits | GC-FID |
| Chloride Content | 23.5–24.5% | Argentometric titration |
Safety & Handling
| Parameter | Specification |
|---|---|
| Storage Conditions | 2–8°C, dry, inert atmosphere |
| Shelf Life | 24 months in sealed container |
| Hazard Classification | Harmful if swallowed/inhaled |
| PPE Requirements | Gloves, goggles, lab coat |
| Incompatibilities | Strong oxidizers, bases |
Regulatory Compliance
| Standard | Status |
|---|---|
| REACH Registered | Yes (EC 200-753-8) |
| FDA IIG Database | Listed for pharmaceutical use |
| EP/BP Compliance | Meets general monograph |
| TSCA Listed | Yes (US) |
| China Inventory | IECSC Listed |
Conclusion
4-Aminophenol hydrochloride is a versatile chemical intermediate with critical applications in pharmaceuticals, dyes, and specialty chemicals. Its high purity and stability make it suitable for GMP manufacturing processes.


