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Bromoethane - Wikipedia

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Bromoethane
Skeletal formula of bromoethane
Skeletal formula of bromoethane
Skeletal formula of bromoethane with all explicit hydrogens added
Skeletal formula of bromoethane with all explicit hydrogens added
Ball and stick model of bromoethane
Ball and stick model of bromoethane
Spacefill model of bromoethane
Spacefill model of bromoethane
Names
Preferred IUPAC name

Bromoethane[2]

Other names

Ethyl bromide[1]
Monobromoethane[1]

Identifiers

3D model (JSmol)
1209224
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.751 Edit this at Wikidata
EC Number
  • 200-825-8
KEGG
MeSH bromoethane
RTECS number
  • KH6475000
UNII
UN number 1891

  • InChI=1S/C2H5Br/c1-2-3/h2H2,1H3 check

    Key: RDHPKYGYEGBMSE-UHFFFAOYSA-N check

  • CCBr

Properties
C2H5Br
Molar mass 108.966 g·mol−1
Appearance Colorless liquid
Odor ether-like
Density 1.46 g mL−1
Melting point −120 to −116 °C; −184 to −177 °F; 153 to 157 K
Boiling point 38.0 to 38.8 °C; 100.3 to 101.8 °F; 311.1 to 311.9 K
1.067 g/100 mL (0 °C)
0.914 g/100 mL (20 °C)
0.896 g/100 mL (30 °C)
Solubility miscible with ethanol, ether, chloroform, organic solvents
log P 1.809
Vapor pressure 51.97 kPa (at 20 °C)
1.3 μmol Pa−1 kg−1
-54.70·10−6 cm3/mol
1.4225
Viscosity 402 Pa.s (at 20 °C)
Thermochemistry
105.8 J K−1 mol−1
−97.6–93.4 kJ mol−1
Hazards
GHS labelling:
GHS02: Flammable GHS06: Toxic GHS08: Health hazard
Danger
H225, H302, H332, H351
P210, P281
NFPA 704 (fire diamond)
NFPA 704 four-colored diamond

3

1

0

Flash point −23 °C (−9 °F; 250 K)
511 °C (952 °F; 784 K)
Explosive limits 6.75–11.25%
Lethal dose or concentration (LD, LC):
1.35 g kg−1 (oral, rat)
26,980 ppm (rat, 1 hr)
16,230 ppm (mouse, 1 hr)
4681 ppm (rat)
2723 ppm (mouse)[3]
3500 ppm (mouse)
24,000 ppm (guinea pig, 30 min)
7000 ppm (guinea pig, >4.5 hr)[3]
NIOSH (US health exposure limits):

PEL (Permissible)

 TWA 200 ppm (890 mg/m3)[1]

REL (Recommended)

 None established[1]

IDLH (Immediate danger)

 2000 ppm[1]
Related compounds

Related alkanes

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

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Bromoethane, also known as ethyl bromide, is a chemical compound of the haloalkanes group. It is abbreviated by chemists as EtBr (which is also used as an abbreviation for ethidium bromide). This volatile compound has an ether-like odor.

The preparation of EtBr stands as a model for the synthesis of bromoalkanes in general. It is usually prepared by the addition of hydrogen bromide to ethene:

H2C=CH2 + HBr → H3C-CH2Br

Bromoethane is inexpensive and would rarely be prepared in the laboratory. A laboratory synthesis includes reacting ethanol with a mixture of hydrobromic and sulfuric acids. An alternate route involves refluxing ethanol with phosphorus and bromine; phosphorus tribromide is generated in situ.[4]

In organic synthesis, EtBr is the synthetic equivalent of the ethyl carbocation (Et+) synthon.[5] In reality, such a cation is not actually formed. For example, carboxylates salts are converted to ethyl esters,[6] carbanions to ethylated derivatives, thiourea into ethylisothiouronium salts,[7] and amines into ethylamines.[8]

Short chain monohalocarbons in general are potentially dangerous alkylating agents. Bromides are better alkylating agents than chlorides, thus exposure to them should be minimized.

  1. ^ a b c d e NIOSH Pocket Guide to Chemical Hazards. "#0265". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ "bromoethane - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 26 March 2005. Identification. Retrieved 15 June 2012.
  3. ^ a b "Ethyl bromide". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. ^ Oliver Kamm & C. S. Marvel (1941). "Alkyl and alkylene bromides". Organic Syntheses; Collected Volumes, vol. 1, p. 25.
  5. ^ Makosza, M.; Jonczyk, A. "Phase-Transfer Alkylation of Nitriles: 2-Phenylbutyronitrile". Organic Syntheses. 55: 91; Collected Volumes, vol. 6, p. 897.
  6. ^ Petit, Y.; Larchevêque, M. "Ethyl Glycidate from (S)-Serine: Ethyl (R)-(+)-2,3-Epoxypropanoate". Organic Syntheses. 75: 37; Collected Volumes, vol. 10, p. 401.
  7. ^ E. Brand; Brand, F. C. "Guanidodacetic Acid". Organic Syntheses. 22: 440; Collected Volumes, vol. 3.
  8. ^ Brasen, W. R; Hauser, C. R. "o-Methylethylbenzyl Alcohol". Organic Syntheses. 34: 58; Collected Volumes, vol. 4, p. 582.