Misplaced Pages

Benzyl bromide

Names
Preferred IUPAC name (Bromomethyl)benzene
Other names α-Bromotoluene Benzyl bromide
Identifiers
CAS Number	100-39-0
3D model (JSmol)	Interactive image Interactive image
ChEBI	CHEBI:59858
ChEMBL	ChEMBL1085946
ChemSpider	13851576
ECHA InfoCard	100.002.589
IUPHAR/BPS	6294
PubChem CID	7498
UNII	XR75BS721D
CompTox Dashboard (EPA)	DTXSID8024658
InChI InChI=1S/C7H7Br/c8-6-7-4-2-1-3-5-7/h1-5H,6H2Key: AGEZXYOZHKGVCM-UHFFFAOYSA-N InChI=1/C7H7Br/c8-6-7-4-2-1-3-5-7/h1-5H,6H2Key: AGEZXYOZHKGVCM-UHFFFAOYAM
SMILES BrCc1ccccc1 c1ccc(cc1)CBr
Properties
Chemical formula	C7H7Br
Molar mass	171.037 g·mol
Appearance	Colorless liquid
Odor	Sharp and pungent
Density	1.438 g/cm
Melting point	−3.9 °C (25.0 °F; 269.2 K)
Boiling point	201 °C (394 °F; 474 K)
Solubility	organic solvents
log P	2.92
Refractive index (nD)	1.5752
Hazards
GHS labelling:
Pictograms
Flash point	70 °C (158 °F; 343 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). N verify (what is  ?) Infobox references

Benzyl bromide is an organic compound with the formula C₆H₅CH₂Br. The molecule consists of a benzene ring substituted with a bromomethyl group. It is a colorless liquid with lachrymatory properties. The compound is a reagent for introducing benzyl groups.

Synthesis and structure

Benzyl bromide can be synthesized by the bromination of toluene under conditions suitable for a free radical halogenation:

The structure has been examined by electron diffraction.

Applications

Benzyl bromide is used in organic synthesis for the introduction of the benzyl groups when the less expensive benzyl chloride is insufficiently reactive. Benzylations are often achieved in the presence of catalytic amounts of sodium iodide, which generates the more reactive benzyl iodide in situ. In some cases, benzyl serves as protecting group for alcohols and carboxylic acids.

Safety

Benzyl bromide is a strong lachrymator and is also intensely irritating to skin and mucous membranes. Because of these properties, it has been used in chemical warfare, both in combat and in training due to its irritating yet non-lethal nature.

See also

• Benzyl chloride
• Benzyl fluoride
• Benzyl iodide
• Xylyl bromide

References

1. Merck Index (11th ed.). p. 1142.
2. "Benzyl bromide_msds".
3. ^ William E. Bauta (2001). "Benzyl Bromide". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rb047. ISBN 0-471-93623-5.
4. "Benzyl bromide". Sigma Aldrich. sigmaaldrich.com. Retrieved 8 June 2017.
5. Vilkov, L. V.; Sadova, N. I. (March 1976). "Electron diffraction study on the molecular structure of benzyl chloride and benzyl bromide in the vapour phase". Journal of Molecular Structure. 31 (1): 131–142. Bibcode:1976JMoSt..31..131S. doi:10.1016/0022-2860(76)80124-X.
6. Andrew G. Myers; Bryant H. Yang (2000). "Synthesis and Diastereoselective Alkylation of Pseudoephenedrine Amides". Org. Synth. 77: 22. doi:10.15227/orgsyn.077.0022.
7. Harry Heaney; Steven V. Ley (1974). "1-Benzylindole". Org. Synth. 54: 58. doi:10.15227/orgsyn.054.0058.
8. "Benzyl bromide". chemicalbook.com. Retrieved 8 June 2017.

• Organobromides
• Benzyl compounds
• Lachrymatory agents