2,4,5-Trichlorophenol
Chemical Additives 2025-03-19
2.4.5-Trichlorophenol Technical Profile
| Category |
Specifications |
| Chemical Name |
2.4.5-Trichlorophenol |
| CAS Number |
95-95-4 |
| Molecular Formula |
C₆H₃Cl₃O |
| Molecular Weight |
197.45 g/mol |
| Appearance |
Gray to brown crystalline solid |
| Melting Point |
68-70°C |
| Boiling Point |
253°C |
| Solubility |
Slightly soluble in water (0.12 g/L at 20°C), soluble in organic solvents |
| Density |
1.678 g/cm³ |
Chemical Properties
| Property |
Characteristics |
| Acidity (pKa) |
6.9-7.2 |
| Stability |
Stable under normal conditions |
| Decomposition |
Releases HCl when heated above 300°C |
| Reactivity |
Forms salts with bases, undergoes electrophilic substitution |
Production Methods
| Process |
Description |
| Chlorination |
Direct chlorination of phenol |
| Hydrolysis |
Hydrolysis of 1.2.4.5-tetrachlorobenzene |
Applications
| Industry |
Use |
| Agriculture |
Formerly used as pesticide intermediate |
| Chemical Synthesis |
Precursor for herbicides and preservatives |
| Pharmaceuticals |
Intermediate for certain drugs (historical) |
Safety & Handling
| Parameter |
Value/Requirement |
| OSHA PEL |
0.5 mg/m³ (8-hour TWA) |
| LD50 (oral, rat) |
820 mg/kg |
| Environmental Impact |
Persistent organic pollutant |
| Storage Requirements |
Cool, dry, ventilated area |
| Personal Protection |
Gloves, goggles, respirator required |
Regulatory Status
| Regulation |
Status |
| Stockholm Convention |
Listed as POP |
| EPA Classification |
Priority pollutant |
| EU REACH |
Restricted substance |
Note: This compound has been largely phased out due to toxicity concerns, particularly regarding dioxin contamination in its derivatives. Current applications are extremely limited and subject to strict regulations.
2,4,5-Trichlorophenol
Chemical Formula: C₆H₃Cl₃O
Structure: Chlorinated phenol with:
- A hydroxyl group (-OH) and three chlorine atoms (-Cl) at the 2, 4, and 5 positions on a benzene ring.
- Asymmetrical substitution pattern.
Physical Properties
- Appearance: White to pale yellow crystalline solid.
- Odor: Strong phenolic odor.
Applications
- Chemical Synthesis:
- Precursor for pesticides, herbicides, and disinfectants.
- Intermediate in dyes, pharmaceuticals, and wood preservatives.
- Specialty Chemicals:
- Production of flame retardants and industrial additives.
Safety Considerations ⚠️
- Toxicity:
- Toxic via inhalation, ingestion, or skin contact; causes severe irritation to skin, eyes, and respiratory tract.
- Handling:
- Use PPE (gloves, goggles, respirator) and work in a well-ventilated area.
- Storage:
- Store in a cool, dry place away from heat and incompatible materials (e.g., strong oxidizers).
Summary:
2,4,5-Trichlorophenol’s chlorinated phenolic structure and asymmetrical reactivity make it critical in agrochemical, disinfectant, and flame-retardant production. Its role in industrial and pharmaceutical synthesis underscores its versatility, but strict safety protocols are essential due to its toxicity and irritant hazards.
