Bromoacetone

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Bromoacetone[1]
Skeletal formula
Ball-and-stick model
Identifiers
CAS number 598-31-2 YesY
PubChem 11715
ChemSpider 11223 YesY
ChEBI CHEBI:51845 YesY
ChEMBL CHEMBL1085947 YesY
RTECS number UC0525000
Jmol-3D images Image 1
Properties
Molecular formula C3H5BrO
Molar mass 136.98 g mol−1
Appearance Colorless lachrymator
Density 1.634 g/cm³
Melting point −36.5 °C (−33.7 °F; 236.7 K)
Boiling point 137 °C (279 °F; 410 K)
Vapor pressure 1.1 kPa (20 °C)
Hazards
MSDS MSDS at ILO
Flash point 51.1 °C (124.0 °F; 324.2 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Bromoacetone is an organic compound with the formula CH3COCH2Br. This colorless liquid is a lachrymatory agent. It is a precursor to other organic compounds.

Occurrence[edit]

Bromoacetone is naturally present (less than 1%) in the essential oil of a seaweed from the vicinity of the Hawaiian Islands.[2]

Synthesis[edit]

Bromoacetone is available commercially, sometimes stabilized with magnesium oxide. It was first described in the 19th century, attributed to N. Sokolowsky.[3]

Acetone and bromine form bromoacetone.

Bromoacetone is prepared by combining bromine and acetone,[4] with catalytic acid. If you use a base you will obtain bromoform instead. CH3C(O)CH3 + Br2 → CH3C(O)CH2Br + HBr The main difficulty with this method is over-bromination, resulting in di- and tribrominated products. In terms of mechanism, as with all ketones, acetone enolizes in the presence of acids or bases. The alpha carbon then undergoes electrophilic substitution with bromine.[5]

Applications[edit]

It was used in World War I as a chemical weapon, called BA by British and B-Stoff (white cross) by Germans. Due to its toxicity, it is obsolete as a riot control agent and is not used anymore. Bromoacetone is a versatile reagent in organic synthesis. It is, for example, the precursor to hydroxyacetone (b.p. 40–43°/12 mm, CAS #116-09-6).[6]

See also[edit]

References[edit]

  1. ^ Merck Index, 11th Edition, 1389
  2. ^ Burreson, B. J.; Moore, R. E.; Roller, P. P. (1976). "Volatile halogen compounds in the alga Asparagopsis taxiformis (Rhodophyta)". Journal of Agricultural and Food Chemistry 24 (4): 856–861. doi:10.1021/jf60206a040. 
  3. ^ Wagner, G. (1876). "Sitzung der russischen chemischen Gesellschaft am 7./19. October 1876". Berichte der Deutschen Chemischen Gesellschaft 9 (2): 1687–1688. doi:10.1002/cber.187600902196. 
  4. ^ Levene, P. A. (1930), "Bromoacetone", Org. Synth. 10: 12 ; Coll. Vol. 2: 88 
  5. ^ Reusch, W. (2013-05-05). "Carbonyl Reactivity". Virtual Textbook of Organic Chemistry. Michigan State University. 
  6. ^ Levene, P. A.; Walti, A. (1930), "Acetol", Org. Synth. 10: 1 ; Coll. Vol. 2: 5