Biphenyl
Names | |
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Preferred IUPAC name
1,1′-Biphenyl | |
Other names
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Identifiers | |
3D model (
JSmol ) |
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3DMet | |
1634058 | |
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard
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100.001.967 |
EC Number |
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E number | E230 (preservatives) |
3808 | |
KEGG | |
PubChem CID
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RTECS number
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UNII | |
UN number | 3077 |
CompTox Dashboard (EPA)
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Properties | |
C12H10 | |
Molar mass | 154.212 g·mol−1 |
Appearance | Colorless to pale-yellow crystals |
Odor | pleasant[1] |
Density | 1.04 g/cm3[2] |
Melting point | 69.2 °C (156.6 °F; 342.3 K)[2] |
Boiling point | 255 °C (491 °F; 528 K)[2] |
4.45 mg/L[2] | |
Vapor pressure | 0.005 mmHg (20°C)[1] |
−103.25·10−6 cm3/mol | |
Hazards | |
GHS labelling: | |
Warning | |
H315, H319, H335, H410 | |
P261, P264, P271, P273, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P391, P403+P233, P405, P501 | |
NFPA 704 (fire diamond) | |
Flash point | 113 °C (235 °F; 386 K)[2] |
540 °C (1,004 °F; 813 K)[2] | |
Explosive limits
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0.6–5.8%[1] |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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2400 mg/kg (oral, rabbit) 3280 mg/kg (oral, rat) 1900 mg/kg (oral, mouse) 2400 mg/kg (oral, rat)[3] |
NIOSH (US health exposure limits): | |
PEL (Permissible)
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TWA 1 mg/m3 (0.2 ppm)[1] |
REL (Recommended)
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TWA 1 mg/m3 (0.2 ppm)[1] |
IDLH (Immediate danger) |
100 mg/m3[1] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Biphenyl (also known as diphenyl, phenylbenzene, 1,1′-biphenyl, lemonene[4] or BP) is an organic compound that forms colorless crystals. Particularly in older literature, compounds containing the functional group consisting of biphenyl less one hydrogen (the site at which it is attached) may use the prefixes xenyl or diphenylyl.[5]
It has a distinctively pleasant smell. Biphenyl is an
Biphenyl is also an intermediate for the production of a host of other
Properties and occurrence
Biphenyl is a solid at room temperature, with a melting point of 69.2 °C (156.6 °F). In the gas phase the molecule exists in two
Biphenyl occurs naturally in
- C6H5CH3 + C6H6 → C6H5−C6H5 + CH4
The other principal route is by the oxidative dehydrogenation of benzene:
- 2 C6H6 + 1/2 O2 → C6H5−C6H5 + H2O
Annually 40,000,000 kg are produced by these routes.[9]
In the laboratory, biphenyl can also be synthesized by treating phenylmagnesium bromide with copper(II) salts.
It can also be prepared using diazonium salts. When aniline is treated with NaNO2+dilute HCl at 5°C, it yields benzene diazonium chloride. When this is further reacted with benzene, biphenyl is formed. This is known as the Gomberg–Bachmann reaction.
Reactions and uses
Lacking functional groups, biphenyl is fairly non-reactive, which is the basis of its main application: its use as a heat transfer agent as a
Biphenyl does undergo
Li biphenyl radical
Lithium biphenyl contains the radical anion, which is highly reducing (-3.1 V vs Fc+/0). Several solvates of alkali metal salts of biphenyl anion have been characterized by X-ray crystallography.[10] These salts, usually prepared in situ, are versatile reducing agents.[11] Lithium biphenyl offers some advantages relative to the related lithium naphthene.[12] Related to Li/biphenyl is the derivative with tert-butyl groups on the biphenyl.[13]
Stereochemistry
Rotation about the single bond in biphenyl, and especially its
Biphenyl compounds
Substituted biphenyls have many uses. They are prepared by various
Safety and bioactivity
Biphenyl prevents the growth of
Biphenyl is mildly toxic, but can be degraded biologically by conversion into nontoxic compounds. Some bacteria are able to hydroxylate biphenyl and its polychlorinated biphenyls (PCBs).[17]
See also
- Naphthalene, where the rings are fused
- Terphenyl, three ringed analog
- Bithiophene
Notes
- ^ a b c d e f NIOSH Pocket Guide to Chemical Hazards. "#0239". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b c d e f Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
- ^ "Diphenyl". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH). 4 December 2014. Retrieved 17 March 2015.
- ^ "Biphenyl". NIST Chemistry WebBook. US National Institute of Standards and Technology. An obscure name, according to "Limonene". Molecule of the Week Archive. American Chemical Society. Nov 1, 2021.
- ^ "Beilsteins Handbuch der organischen Chemie, Volume 5".
- .
- ISSN 0947-6539.
- ^
- .
- .
- .
- .
- PMID 26621432.
- ^ B. Testa (1982). "The geometry of molecules: basic principles and nomenclatures". In Christoph Tamm (ed.). Stereochemistry. Elsevier. p. 18.
- S2CID 97514765.
- ^ "Biphenyl degradation - Streptomyces coelicolor, at GenomeNet Database". genome.jp.
References
- "Isolation and Identification of Biphenyls from West Edmond Crude Oil". N. G. Adams and D. M. Richardson. Analytical Chemistry 1953 25 (7), 1073–1074.
- Biphenyl (1,1-Biphenyl). Wiley/VCH, Weinheim (1991), ISBN 3-527-28277-7.