4-Phenylbutyronitrile, bearing the CAS number 2046-18-6, is a chemical compound widely recognized for its significance in organic synthesis and pharmaceutical applications. A comprehensive understanding of its chemical properties, alongside adherence to strict safety protocols, is paramount for its effective and safe utilization in both research and industrial settings.

The compound's molecular formula is C10H11N, with a molecular weight of approximately 145.20 g/mol. Its physical state at room temperature is typically described as a clear liquid, with variations in color ranging from colorless to greenish or reddish tints, often indicative of purity levels or minor oxidation. Key physicochemical properties include a boiling point around 129-131 °C at 10 mmHg, a density of 0.976 g/mL at 25°C, and a refractive index of 1.5143. Its solubility profile shows good solubility in common organic solvents like ethanol, ether, and benzene, while its water solubility is limited.

From a safety perspective, 4-phenylbutyronitrile is classified as harmful. Hazard statements such as H302+H312+H332 (Harmful if swallowed, in contact with skin, or if inhaled), H315 (Causes skin irritation), H319 (Causes serious eye irritation), and H335 (May cause respiratory irritation) highlight the need for careful handling. Consequently, appropriate personal protective equipment (PPE) such as gloves, eye protection, and respiratory protection should be used when working with this substance. Precautionary statements like P261 (Avoid breathing dust/fume/gas/mist/vapours/spray) and P280 (Wear protective gloves/protective clothing/eye protection/face protection) are critical guidance for safe laboratory and industrial practices.

The chemical reactivity of 4-phenylbutyronitrile is largely dictated by its nitrile functional group (-C≡N), which can undergo various transformations like hydrolysis to carboxylic acids or reduction to amines. This inherent reactivity makes it a valuable building block in complex organic synthesis pathways. By understanding these properties and strictly following the safety guidelines, chemists and manufacturers can effectively leverage 4-phenylbutyronitrile for its intended applications while ensuring a safe working environment.