Bromoacetone

Bromoacetone[1]
IUPAC name 1-Bromoacetone
Other names Bromoacetone 1-Bromo-2-propanone α-Bromoacetone Acetonyl bromide Acetyl methyl bromide Bromomethyl methyl ketone Monobromoacetone Martonite BA UN 1569
Identifiers
CAS number	598-31-2 Y
PubChem	11715
ChemSpider	11223 Y
ChEBI	CHEBI:51845 Y
ChEMBL	CHEMBL1085947 Y
RTECS number	UC0525000
Jmol-3D images	Image 1
SMILES BrCC(=O)C
InChI InChI=1S/C3H5BrO/c1-3(5)2-4/h2H2,1H3 Y Key: VQFAIAKCILWQPZ-UHFFFAOYSA-N Y InChI=1/C3H5BrO/c1-3(5)2-4/h2H2,1H3 Key: VQFAIAKCILWQPZ-UHFFFAOYAC
Properties
Molecular formula	C3H5BrO
Molar mass	136.98 g mol−1
Appearance	Colorless lachrymator
Density	1.634 g/cm³
Melting point	-36.5 °C, 237 K, -34 °F
Boiling point	137 °C, 410 K, 279 °F
Vapor pressure	1.1 kPa (20 °C)
Hazards
MSDS	MSDS at ILO
Flash point	51.1 °C
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

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

Bromoacetone was first prepared in the 19th century.^[2] 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 Due to its toxicity, it is obsolete as a riot control agent and is not used anymore.

Occurrence

Bromoacetone is naturally present (less than 1%) in the essential oil of a seaweed from the vicinity of the Hawaiian Islands.^[3] In atmosphere it is degraded by the photochemically produced hydroxyl radicals.

Synthesis

Bromoacetone is available commercially, sometimes stabilized with magnesium oxide.

Bromoacetone is prepared by reacting bromine and acetone,^[4] with catalytic acid. If you use a base you will obtain bromoform instead. H₃ C(O)CH₃ + Br₂ → CH₃C(O)CH₂Br + HBr

As with all ketones, acetone enolizes in the presence of acids or bases. The alpha carbon then undergoes electrophilic substitution with bromine.^[5] The main difficulty with this method is over-bromination, resulting in di- and tribrominated products.

Applications

Bromoacetone is a versatile reagent in organic synthesis. It is, for example, the precursor to hydroxyacetone (b.p. 35–47°/12 mm, CAS #116-09-6).^[6]

See also

• Use of poison gas in World War I

References

1. ^ Merck Index, 11th Edition, 1389
2. ^ Sokolowsky, Berichte volume 9, pp. 1687 (1876).
3. ^ B. Jay Burreson, Richard E. Moore, and Peter P. Roller (1976). "Volatile halogen compounds in the alga Asparagopsis taxiformis (Rhodophyta)". Journal of Agricultural and Food Chemistry 24 (4): 856–861. doi:10.1021/jf60206a040. 
4. ^ Levene, P. A. (1943), "Bromoacetone", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv2p0088 ; Coll. Vol. 2: 88 
5. ^ William Reusch. "Carbonyl Reactivity". VirtualText of Organic Chemistry. http://www.cem.msu.edu/~reusch/VirtualText/aldket2.htm. Retrieved 2007-10-27. 
6. ^ Levene, P. A.; Walti, A. (1943), "Acetol", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv2p0005 ; Coll. Vol. 2: 5