| 1,2-Dibromoethane | |
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1,2-dibromoethane |
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Other names
ethylene dibromide |
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| Identifiers | |
| CAS number | 106-93-4 |
| ChemSpider | 7551 |
| KEGG | C11088 |
| ChEBI | CHEBI:28534 |
| ChEMBL | CHEMBL452370 |
| RTECS number | KH9275000 |
| Jmol-3D images | Image 1 |
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| Properties | |
| Molecular formula | C2H4Br2 |
| Molar mass | 187.86 g/mol |
| Appearance | colorless liquid |
| Density | 2.17 g/cm³, liquid |
| Melting point |
9-10 °C |
| Boiling point |
131-132 °C |
| Solubility in water | 1 part in 250 |
| Hazards | |
| R-phrases | R45, R23/24/25, R36/37/38, R51/53 |
| S-phrases | S53, S45, S61 |
| NFPA 704 |
0
3
0
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| Flash point | >104 °C |
| Related compounds | |
| Related organobromides | bromoethane 1,1-Dibromoethane |
| Related compounds | 1,2-dichloroethane |
| (verify) (what is: /?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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| Infobox references | |
1,2-Dibromoethane, also known as ethylene dibromide (EDB), is the chemical compound with the formula BrCH2CH2Br. Although trace amounts occur naturally in the ocean, where it is formed probably by algae and kelp, it is mainly a synthetic. This a colorless liquid with a sweet odor, detectable at 10 ppm, is a widely used and sometimes-controversial fumigant.
Contents |
It is manufactured by the reaction of ethylene with bromine, in a classic halogen addition reaction:
The once-dominant use, although one that has faded, is as an additive in leaded gasoline. 1,2-Dibromoethane reacts with lead residues to generate volatile lead bromides. It has been used as a pesticide in soil and on various crops. The applications were initiated after the forced retirement of 1,2-dibromo-3-chloropropane (DBCP). Most of these uses have been stopped in the U.S. It continues to be used as a fumigant for treatment of logs for termites and beetles, for control of moths in beehives, and as a preparation for dyes and waxes.[1]
1,2-Dibromoethane is used in organic synthesis as a source of bromine, e.g., to brominate carbanions and to activate magnesium for certain Grignard reagents. In the latter process, the 1,2-dibromoethane is converted to ethylene and magnesium bromide, exposing a freshly etched portion of magnesium to the substrate.[2]
Historically, 1,2-dibromoethane was used as an anti-knock additive in leaded fuels.[3]
The effects on people of breathing high levels are not known, but animal studies with short-term exposures to high levels caused depression and collapse, indicating effects on the brain.[4]
Redness and inflammation, including skin blisters and mouth and stomach ulcers, can occur if large amounts are swallowed. Swallowing has caused death at 40 mL doses[1]. It is highly unlikely that there would be a risk of death to people from low-level exposure.
Although very little is known about the effects from breathing 1,2-dibromoethane over a long period of time, some male workers had reproductive effects including damage to their sperm.
In rats, death occurred from breathing high levels for a short time. Lower levels caused liver and kidney damage. When rats breathed air or ate food containing 1,2-dibromoethane for short or long periods of time, they were less fertile or had abnormal sperm.
Changes in the brain and behavior were also seen in young rats whose male parents had breathed 1,2-dibromoethane, and birth defects were observed in the young of animals that were exposed while pregnant. 1,2-Dibromoethane is not known to cause birth defects in humans.[4]
It is a known carcinogen, with pre-1977 exposure levels ranking it as the most carcinogenic substance on the HERP Index.[5]
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