| 1,2-Dibromoethane |
|---|
 1,2-Dibromoethane  1,2-Dibromoethane |
| General | |
|---|---|
| Systematic name | 1,2-dibromoethane |
| Other names | ethylene dibromide ethylene bromide EDB glycol bromide ethylene bromide, Bromofume (trade name), Dowfume (trade name) |
| Molecular formula | C2H4Br2 |
| SMILES | C(Br)CBr |
| Molar mass | 187.86 g/mol |
| Appearance | colorless liquid |
| CAS number | [106-93-4] |
| Properties |
|---|
| Density and phase | 2.17 g/cm³, liquid |
| Solubility in water | 1 part in 250 |
| Melting point | 9-10 °C (? K) |
| Boiling point | 131-132 °C (? K) |
| Hazards |
|---|
| MSDS | External MSDS |
| Main hazards | ? |
| NFPA 704 | |
| Flash point | >104 °C |
| R/S statement | R: , , , S: , , |
| RTECS number | KH9275000 |
| Related compounds |
|---|
| Related organobromides | bromoethane 1,1-dibromoethane |
| Related compounds | 1,2-dichloroethane |
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
|
'1,2-Dibromoethane' is the
chemical compound with the formula BrCH
2CH
2Br. Although trace amounts occurs naturally in the
ocean where it is formed, probably by
algae and
kelp, it is mainly a synthetic. It is a colorless liquid with a mild, sweaty odor.
Preparation and structure
It is manufactured by the reaction of
ethylene with
bromine:
:CH
2=CH
2 + Br
2 → BrCH
2CH
2Br
Uses
1,2-Dibromoethane is used in
organic synthesis as an "entrainment reagent" to activate
magnesium for certain
Grignard reagents. In this process, the 1,2-dibromoethane is converted to ethylene and magnesium bromide, exposing a freshly etched portion of magnesium to the substrate.
[1]
1,2-Dibromoethane is a precursor to many 1,2-disubstituted ethane derivatives, e.g.
1,2-ethanedithiol.
In some cases, 1,2-dibromoethane is used to brominate carbanions.
Another major use, although one that is fading in importance, is as an additive in leaded
gasoline.
As a pesticide and fumigant
1,2-Dibromoethane has been used as a
pesticide in
soil, and on
citrus,
vegetable, and
cereal crops. Most of these uses have been stopped by the
United States Environmental Protection Agency (EPA) since 1984. Uses today include a
fumigant for treatment of logs for
termites and
beetles, control of
moths in
beehives, and as a preparation for
dyes and
waxes.
Health effects
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.
[2]
Redness and
inflammation, including
skin blisters and
mouth and
stomach ulcers, can occur if large amounts are swallowed. One accidental swallowing caused death in a woman. 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.
[2]
References
1. Maynard, G. D. "1,2-Dibromoethane" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. DOI: 10.1002/047084289.
2. ToxFAQs for 1,2-Dibromoethane
3. ToxFAQs for 1,2-Dibromoethane
External links
★
National Pollutant Inventory 1,2-Dibromoethane Fact Sheet
★
Congressional Research Service (CRS) Reports regarding Ethylene Dibromide