cyclopentane

Cyclopentane
IUPAC name	Cyclopentane
Other names	pentamethylene
Identifiers
CAS number	[287-92-3]
PubChem	9253
RTECS number	GY2390000
SMILES	C1CCCC1
Properties
Molecular formula	C5H10
Molar mass	70.1 g/mol
Appearance	clear, colorless liquid
Density	0.751 g/cm3
Melting point	−94 °C
Boiling point	49 °C, 322 K, 120 °F
Acidity (pKa)	~45
Related compounds
Related compounds	cyclopropane, cyclobutane, cyclohexane
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references

Cyclopentane is a highly flammable alicyclic hydrocarbon with chemical formula C₅H₁₀ and CAS number 287-92-3, consisting of a ring of five carbon atoms each bonded with two hydrogen atoms above and below the plane. It occurs as a colorless liquid with a petrol-like odor. Its melting point is −94 °C and its boiling point is 49 °C.

The typical structure of cyclopentane is the "envelope" conformation.

Industrial usage

Cyclopentane is used in the manufacture of synthetic resins and rubber adhesives and also as a blowing agent in the manufacture of polyurethane insulating foam, as found in may domestic appliances such as refrigerators and freezers, replacing environmentally damaging alternatives such as CFC-11 and HCFC-141b^[1]

More advanced technologies, such as computer hard drives and outerspace equipment employ multiply-alkylated cyclopentane (MAC) lubricants because of their extremely low volatility.^[2]

The United States produces more than half a million kilograms of this chemical per year.

Formulation of cycloalkanes

Cycloalkanes can be formulated via a process known as catalytic reforming.

For example, 2-methylbutane can be reformed into cyclopentane, by use of a platinum catalyst. This is particularly well known in automobiles, as branched alkanes will burn much more readily.

References