1-Bromobutane

1-Bromobutane
Skeletal formula of 1-bromobutane with some implicit hydrogens shown
Skeletal formula of 1-bromobutane with some implicit hydrogens shown
Ball and stick model of 1-bromobutane
Ball and stick model of 1-bromobutane
Names
Preferred IUPAC name
1-Bromobutane[1]
Other names
Butyl bromide
Identifiers
CAS Number
3D model (JSmol)
Beilstein Reference
1098260
ChEMBL
ChemSpider
ECHA InfoCard 100.003.357
EC Number
  • 203-691-9
MeSH butyl+bromide
PubChem CID
RTECS number
  • EJ6225000
UNII
UN number 1126
CompTox Dashboard (EPA)
InChI
  • InChI=1S/C4H9Br/c1-2-3-4-5/h2-4H2,1H3 checkY
    Key: MPPPKRYCTPRNTB-UHFFFAOYSA-N checkY
SMILES
  • CCCCBr
Properties
Chemical formula
C4H9Br
Molar mass 137.020 g·mol−1
Appearance Colourless liquid
Density 1.2676 g mL−1
Melting point −112.5 °C; −170.4 °F; 160.7 K
Boiling point 101.4 to 102.9 °C; 214.4 to 217.1 °F; 374.5 to 376.0 K
log P 2.828
Vapor pressure 5.3 kPa
Henry's law
constant (kH)
140 nmol Pa kg−1
Refractive index (nD)
1.439
Thermochemistry
Heat capacity (C)
162.2 J K−1 mol−1
Std molar
entropy (S298)
327.02 J K−1 mol−1
Std enthalpy of
formation fH298)
−148 kJ mol−1
Std enthalpy of
combustion cH298)
−2.7178–−2.7152 MJ mol−1
Hazards
GHS labelling:
Pictograms
GHS02: Flammable GHS07: Exclamation mark GHS09: Environmental hazard
Signal word
Danger
Hazard statements
H225, H315, H319, H335, H411
Precautionary statements
P210, P261, P273, P305+P351+P338
Flash point 10 °C (50 °F; 283 K)
Autoignition
temperature
265 °C (509 °F; 538 K)
Explosive limits 2.8–6.6%
Lethal dose or concentration (LD, LC):
LD50 (median dose)
2.761 g kg−1 (oral, rat)
Related compounds
Related alkanes
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)
Infobox references

1-Bromobutane is the organobromine compound with the formula CH3(CH2)3Br. It is a colorless liquid, although impure samples appear yellowish. It is insoluble in water, but soluble in organic solvents. It is primarily used as a source of the butyl group in organic synthesis. It is one of several isomers of butyl bromide.

Synthesis

Most 1-bromoalkanes are prepared by free-radical addition of hydrogen bromide to the 1-alkene. These conditions lead to the anti-Markovnikov addition, i.e. give the 1-bromo derivatives.[2]

1-Bromobutane can also be prepared from butanol by treatment with hydrobromic acid:[3]

CH3(CH2)3OH + HBr → CH3(CH2)3Br + H2O

Reactions

As a primary haloalkane, it is prone to SN2 type reactions. It is commonly used as an alkylating agent. When combined with magnesium metal in dry ether, it gives the corresponding Grignard reagent. Such reagents are used to attach butyl groups to various substrates.

1-Bromobutane is the precursor to n-butyllithium:[4]

2 Li + C4H9X → C4H9Li + LiX
where X = Cl, Br

The lithium for this reaction contains 1-3% sodium. When bromobutane is the precursor, the product is a homogeneous solution, consisting of a mixed cluster containing both LiBr and LiBu.

1-Fluorobutane can be obtained by reacting 1-bromobutane with potassium fluoride in ethylene glycol.[5]

See also

References

  1. ^ "butyl bromide - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 27 March 2005. Identification. Retrieved 17 June 2012.
  2. ^ Dagani, M. J.; Barda, H. J.; Benya, T. J.; Sanders, D. C. "Bromine Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a04_405. ISBN 978-3-527-30673-2.
  3. ^ Oliver Kamm, C. S. Marvel, R. H. Goshorn, Thomas Boyd, And E. F. Degering "Alkyl And Alkylene Bromides" Org. Synth. 1921, volume 1, p. 3. doi:10.15227/orgsyn.001.0003
  4. ^ Brandsma, L.; Verkraijsse, H. D. (1987). Preparative Polar Organometallic Chemistry I. Berlin: Springer-Verlag. ISBN 3-540-16916-4.
  5. ^ "1-Fluorobutane". Journal of the Chemical Society. The Society: 1322. 1964. Retrieved 6 August 2024.