cyclopentanes

Cyclopentane is the cycloalkane with the molecular formula C5H10. It comprises a five-membered ring of sp3-hybridized carbon atoms and is the simplest saturated ring beyond cyclopropane and cyclobutane. The ring adopts a puckered envelope conformation, which reduces angle strain relative to a planar pentagon.

Physically, cyclopentane is a colorless, flammable liquid at room temperature. Its boiling point is about 49 °C and its melting point is around −94 °C. It is insoluble in water and soluble in nonpolar organic solvents.

Chemically, it behaves as a typical alkane: relatively unreactive under ordinary conditions, but it can undergo combustion and radical halogenation under UV light or heat to form cyclopentyl halides. It is not aromatic and does not exhibit stereoisomerism.

Occurrence and production: Cyclopentane occurs in small amounts in fossil fuels. Industrially, it is produced by hydrogenation of cyclopentene or by refining and cracking of larger hydrocarbons, and it can be isolated by standard purification techniques.

Applications: It serves as a solvent in chemical synthesis and as a starting material for cyclopentyl derivatives. It is also used as a blowing agent in polyurethane foams and as a reference compound in physical organic studies. Safety considerations include its flammability and the need to avoid ignition sources in handling and storage.