Ethyl bromoacetate

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Ethyl bromoacetate
Skeletal formula of ethyl bromoacetate
Ball-and-stick model of ethyl bromoacetate
IUPAC name Ethyl bromoacetate
Other names Bromoacetic acid
ethyl ester, Antol,
(Ethoxycarbonyl)-
methyl bromide
Identifiers
CAS number [105-36-2]
RTECS number AF6000000
SMILES BrC(CO)OCC
Properties
Molecular formula C4H7O2Br
Molar mass 167.01 g/mol
Appearance colourless to yellow liquid
Density 1.51 g/cm3, liquid
Melting point

-38 °C (199 K)

Boiling point

158 °C (431 K)

Solubility in water Insoluble
Hazards
EU classification Very toxic (T+)
NFPA 704
0
3
0
 
R-phrases R26/27/28
S-phrases (S1/2), S7/9, S26, S45
Flash point 47 °C
Related compounds
Other anions Ethyl acetoacetate
Ethyl iodoacetate
Related esters Methyl bromoacetate
Related compounds Pepper spray
Chloropicrin
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Ethyl 2-bromoacetate is the chemical compound with the formula CH2BrCO2C2H5. It is the ethyl ester of bromoacetic acid and is prepared in two steps from acetic acid[1]

[edit] Applications

In World War I, ethyl bromoacetate was used as a lachrymatory agent and tear gas agent for chemical warfare under the German code Weisskreuz (White Cross), and later as odorant or warning agent in odourless, toxic gases. It is listed by the WHO as a riot control agent, and was first employed for that purpose by French police in 1912. The French may have employed gas grenades of this substance in 1914 during World War I. The German army then used this attack to justify their subsequent employment of chemical weapons in 1915.[2]

In organic synthesis, it is a versatile alkylating agent. Its major application involves the Reformatskii reaction, wherein it reacts with zinc to form a zinc enolate. The resulting BrZnCH2CO2Et condenses with carbonyl compounds to give a β-hydroxy-esters.

It is also the starting point for the preparation of several other reagents. For example, the related Wittig reagent (prepared by reaction with triphenylphosphine) is commonly used to prepare alpha,beta-unsaturated esters from carbonyl compounds such as benzaldehyde:[1]

Ethyl bromoacetate as the starting point for a Wittig reaction sequence


[edit] References

  1. ^ Natelson, S.; Gottfried, S. "Ethyl Bromoacetate" Organic Syntheses, Collected Volume 3, p.381 (1955). http://www.orgsyn.org/orgsyn/pdfs/CV3P0381.pdf (this procedure describes the conversion of acetic acid into bromoacetic acid).
  2. ^ Heller, Charles E. (September 1984). Chemical Warfare in World War I: The American Experience, 1917-1918. Combat Studies Institute. Retrieved on 2007-08-02.
  1. Chemicalland properties database
  2. Environmental Health & Safety dept, Northeastern University
  3. Public health response to biological and chemical weapons, Chapter 3 Biological and Chemical agents, WHO Guidance
  4. ^  A student lab procedure for the Wittig sequence shown, only using the related methyl ester.