Substance profile
2,4-DB (ISO)
2,4-DB (ISO) is white crystals with a slightly phenolic odor.
01 · Identification
What 2,4-DB (ISO) is
2,4-DB (ISO) is white crystals with a slightly phenolic odor. Its molecular formula is C10H10Cl2O3 and its molecular weight is 249.09 g/mol. It melts at 119 °C.
Under the GHS it carries the signal word Warning.
Other names for 2,4-DB (ISO)
- 4-(2,4-dichlorophenoxy)butyric acid
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H302 | Harmful if swallowed. |
| H411 | Toxic to aquatic life with long lasting effects. |
Precautionary statements: P270, P273, P301, P312, P330, P391, P501
03 · Physical and chemical properties
2,4-DB (ISO) properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 119 °C (246.2 °F) | range, midpoint shown | HSDB |
| Solubility | Readily soluble in acetone, ethanol, and diethyl ether. Slightly soluble in benzene, toluene, and kerosene. | HSDB | |
| Water solubility: 46 ppm at 25 °C. | at 25 °C | HSDB | |
| Vapor pressure | 0.0000111 mmHg | Haz-Map | |
| Corrosivity | The acid is slightly corrosive to iron. | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling 2,4-DB (ISO)
Incompatible materials
In an altered process to prepare 2,4-dichlorophenoxybutyric acid, the lactone /butyrolactone/ was added to the other components, and soon after, the reaction temperature reached 165 °C, higher than the usual 160 °C. Application of cooling failed to check the thermal runaway, and soon after reaching 180 °C the vessel began to fail and an explosion and fire occurred.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
2,4-DB is an organic acid. Neutralizes bases in exothermic reactions. Forms water soluble metal and amine salts. Hard water precipitates the calcium and magnesium salts from aqueous solutions of such salts.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check 2,4-DB (ISO) in the storage compatibility matrix →