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Benzonitrile, the simplest cyanoaromatic, is a clear liquid with an almond-like odor. Methods for synthesizing it include
- heating sodium benzenesulfonate with NaCN,
- adding benzenediazonium chloride to a hot aqueous solution of NaCN and CuSO4,
- oxidizing toluene in the presence of ammonia,
- dehydrating benzamide, and
- treating bromobenzene with CuCN or NaCN.
Despite these many synthetic methods, the only uses for benzonitrile are as a solvent or a precursor to benzoguanamine, a derivative of melamine. But recently, the molecule was the subject of a 鈥渟tellar鈥� discovery.
Brett A. McGuire, at the National Radio Astronomy Observatory in Charlottesville, VA, and collaborators . They estimate that the dust cloud is 430 light-years away. This is the first aromatic molecule to be discovered in space, even though astrochemists estimate that 10% of all interstellar carbon consist of polynuclear aromatics.
Benzonitrile聽hazard information
GHS classification*: flammable liquids, category 4. | |
H227鈥擟ombustible liquid | ![]() |
GHS classification: acute toxicity, oral, category 4 | |
H302鈥擧armful if swallowed | ![]() |
GHS classification: acute toxicity, dermal, category 4 | |
H312鈥� Harmful in contact with skin | ![]() |
GHS classification: hazardous to the aquatic environment, acute hazard, category 3 | |
H402鈥擧armful to aquatic life聽 | ![]() |
*Globally Harmonized System of Classification and Labeling of Chemicals.聽.
Benzonitrile聽fast facts
CAS Reg. No. | 100-47-0 |
Molar mass | 103.12 g/mol聽 |
Empirical formula | C7H5N |
Appearance | Colorless liquid |
Boiling point | 191 掳C |
Water solubility | <5 g/L |

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