Benzonitrile
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Names | |||
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Preferred IUPAC name
Benzonitrile | |||
Systematic IUPAC name
Benzenecarbonitrile | |||
Other names | |||
Identifiers | |||
3D model (JSmol)
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ChEBI | |||
ChEMBL | |||
ChemSpider | |||
ECHA InfoCard | 100.002.596 | ||
KEGG | |||
PubChem CID
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RTECS number |
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UNII | |||
CompTox Dashboard (EPA)
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Properties | |||
C7H5N | |||
Molar mass | 103.12 g/mol | ||
Density | 1.0 g/ml | ||
Melting point | −13 °C (9 °F; 260 K) | ||
Boiling point | 188 to 191 °C (370 to 376 °F; 461 to 464 K) | ||
<0.5 g/100 ml (22 °C) | |||
-65.19·10−6 cm3/mol | |||
Refractive index (nD)
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1.5280 | ||
Hazards | |||
NFPA 704 (fire diamond) | |||
Flash point | 75 °C (167 °F; 348 K) | ||
550 °C (1,022 °F; 823 K) | |||
Explosive limits | 1.4–7.2% | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Benzonitrile is the chemical compound with the formula C6H5CN, abbreviated PhCN. This aromatic organic compound is a colorless liquid with a sweet almond odour. It is mainly used as a precursor to the resin benzoguanamine.
Production
It is prepared by ammoxidation of toluene, that is its reaction with ammonia and oxygen (or air) at 400 to 450 °C.[1]
- C6H5CH3 + 3/2 O2 + NH3 → C6H5CN + 3 H2O
In the laboratory it can be prepared by the dehydration of benzamide or by the Rosenmund-von Braun reaction using cuprous cyanide or NaCN/DMSO and bromobenzene.
Applications
Laboratory uses
Benzonitrile is a useful solvent and a versatile precursor to many derivatives. It reacts with amines to afford N-substituted benzamides after hydrolysis.[2] It is a precursor to Ph2C=NH (b.p. 151 °C, 8 mm Hg) via reaction with phenylmagnesium bromide followed by methanolysis.[3]
Benzonitrile forms coordination complexes with transition metals that are both soluble in organic solvents and conveniently labile. One example is PdCl2(PhCN)2. The benzonitrile ligands are readily displaced by stronger ligands, making benzonitrile complexes useful synthetic intermediates.[4]
History
Benzonitrile was reported by Hermann Fehling in 1844. He found the compound as a product from the thermal dehydration of ammonium benzoate. He deduced its structure from the already known analogue reaction of ammonium formate yielding formonitrile. He also coined the name benzonitrile which gave the name to all the group of nitriles.[5]
References
- ^ Takao Maki, Kazuo Takeda "Benzoic Acid and Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a03_555.
- ^ Cooper, F.C.; Partridge, M. W. (1963). "N-Phenylbenzamidine". Organic Syntheses; Collected Volumes, vol. 4, p. 769.
- ^ Pickard, P. L.; Tolbert, T. L. (1973). "Diphenyl Ketimine". Organic Syntheses; Collected Volumes, vol. 5, p. 520.
- ^ Gordon K. Anderson; Minren Lin (1990). "Bis(Benzonitrile)Dichloro Complexes of Palladium and Platinum". Inorganic Syntheses. Inorganic Syntheses. 28: 60–63. doi:10.1002/9780470132593.ch13. ISBN 978-0-470-13259-3.
- ^ Hermann Fehling (1844). "Ueber die Zersetzung des benzoësauren Ammoniaks durch die Wärme". Annalen der Chemie und Pharmacie. 49 (1): 91–97. doi:10.1002/jlac.18440490106.