Benzonitrile is the chemical compound with the formula C6H5(CN), abbreviated PhCN. This aromatic organic compound is a colorless liquid with a sweet bitter almond odour. It is mainly used as a precursor to the resin benzoguanamine.
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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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| 3DMet | |||
| 506893 | |||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.002.596 | ||
| EC Number |
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| 2653 | |||
| KEGG | |||
PubChem CID
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| RTECS number |
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| UNII | |||
| UN number | 2224 | ||
CompTox Dashboard (EPA)
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| Properties | |||
| C6H5(CN) | |||
| 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 | |||
| GHS labelling: | |||
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| Warning | |||
| H302, H312 | |||
| P264, P270, P280, P301+P312, P302+P352, P312, P322, P330, P363, P501 | |||
| 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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Production
editIt is prepared by ammoxidation of toluene, that is its reaction with ammonia and oxygen (or air) at 400 to 450 °C (752 to 842 °F).[1]
- C6H5CH3 + 3/2 O2 + NH3 → C6H5(CN) + 3 H2O
In the laboratory it can be prepared by the dehydration of benzamide or benzaldehyde oxime[2] or by the Rosenmund–von Braun reaction using cuprous cyanide or NaCN/DMSO and bromobenzene.
Applications
editLaboratory uses
editBenzonitrile is a useful solvent and a versatile precursor to many derivatives. It reacts with amines to afford N-substituted benzamides after hydrolysis.[3] It is a precursor to diphenylmethanimine via reaction with phenylmagnesium bromide followed by methanolysis.[4]
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.[5]
History
editBenzonitrile 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 hydrogen cyanide (formonitrile). He also coined the name benzonitrile which gave the name to all the group of nitriles.[6]
In 2018, benzonitrile was reported to be detected in the interstellar medium.[7]
References
edit- ^ Maki, Takao; Takeda, Kazuo (June 2000). "Benzoic Acid and Derivatives". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a03_555. ISBN 3527306730.
- ^ Loupy, André; Régnier, Serge (August 1999). "Solvent-free microwave-assisted Beckmann rearrangement of benzaldehyde and 2-hydroxyacetophenone oximes". Tetrahedron Letters. 40 (34): 6221–6224. doi:10.1016/S0040-4039(99)01159-4. ISSN 0040-4039.
- ^ 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.
- ^ Anderson, Gordon K.; Lin, Minren (1990). "Bis(Benzonitrile)Dichloro Complexes of Palladium and Platinum". Reagents for Transition Metal Complex and Organometallic Syntheses. Inorganic Syntheses. Vol. 28. John Wiley & Sons. pp. 60–63. doi:10.1002/9780470132593.ch13. ISBN 978-0-470-13259-3.
- ^ Fehling, Hermann (1844). "Ueber die Zersetzung des benzoësauren Ammoniaks durch die Wärme". Annalen der Chemie und Pharmacie. 49 (1): 91–97. doi:10.1002/jlac.18440490106.
- ^ McGuire, Brett A.; et al. (January 2018). "Detection of the aromatic molecule benzonitrile (c\sC6H5CN) in the interstellar medium". Science. 359 (6372): 202–205. arXiv:1801.04228. Bibcode:2018Sci...359..202M. doi:10.1126/science.aao4890. PMID 29326270. S2CID 206663501.