CHEMICAL AND PHYSICAL PROPERTIES
| Physical Description | 3,3'-dichlorobenzidine is a gray to purple crystalline powder. Insoluble in water. Very toxic. Used in the dye industry, curing agent for isocyanate terminated resins. |
|---|---|
| Color/Form | Needles from alcohol or benzene |
| Boiling Point | 788 °F at 760 mmHg (NIOSH, 2023) |
| Melting Point | 270 to 271 °F (NTP, 1992) |
| Solubility | 0.07 % at 59 °F (NIOSH, 2023) |
| LogP | log Kow = 3.51 |
| Autoignition Temperature | 350 °C |
| Decomposition | When heated to decomposition it emits very high toxic fumes of /hydrogen chloride and nitrogen oxides./ |
| pH | Weak base |
| Dissociation Constants | pKa1 = 1.6; pKa2 = 3.2 |
| Kovats Retention Index | 2416.64 2406.1 |
| Other Experimental Properties | Undergoes usual reactions of benzidine derivatives, e.g., formation of diazonium salts and alkyl derivatives |
| Chemical Classes | Nitrogen Compounds -> Benzidine and Derivatives |
SAFETY INFORMATION
| Signal word | Danger |
|---|---|
| Pictogram(s) |
 Exclamation Mark Irritant GHS07  Health Hazard GHS08  Environment GHS09 |
| GHS Hazard Statements |
H312:Acute toxicity,dermal H317:Sensitisation, Skin H350:Carcinogenicity H410:Hazardous to the aquatic environment, long-term hazard |
| Precautionary Statement Codes |
P201:Obtain special instructions before use. P202:Do not handle until all safety precautions have been read and understood. P273:Avoid release to the environment. P280:Wear protective gloves/protective clothing/eye protection/face protection. P308+P313:IF exposed or concerned: Get medical advice/attention. |
COMPUTED DESCRIPTORS
| Molecular Weight | 253.12 g/mol |
|---|---|
| XLogP3 | 3.5 |
| Hydrogen Bond Donor Count | 2 |
| Hydrogen Bond Acceptor Count | 2 |
| Rotatable Bond Count | 1 |
| Exact Mass | 252.0221037 g/mol |
| Monoisotopic Mass | 252.0221037 g/mol |
| Topological Polar Surface Area | 52 Ų |
| Heavy Atom Count | 16 |
| Formal Charge | 0 |
| Complexity | 213 |
| Isotope Atom Count | 0 |
| Defined Atom Stereocenter Count | 0 |
| Undefined Atom Stereocenter Count | 0 |
| Defined Bond Stereocenter Count | 0 |
| Undefined Bond Stereocenter Count | 0 |
| Covalently-Bonded Unit Count | 1 |
| Compound Is Canonicalized | Yes |
PRODUCT INTRODUCTION
description
3,3'-Dichlorobenzidine is a gray-to-purple colored crystalline solid. It changes from a solid to a gas very slowly. 3,3'-Dichlorobenzidine salt is the major form in actual use. It is a stable, off-white colored crystalline solid that does not evaporate. Neither 3,3'-dichlorobenzidine nor its salt are found naturally in the environment. They are manufactured for pigments for printing inks, textiles, plastics and enamels, paint, leather, and rubber.