Cyclopentanone is also called AdipicKetono. It is a colorless, transparent, oily liquid. It has a special ethereal and slightly minty smell. The relative molecular mass is 84.12. The relative density is 0.9487. The melting point is -51.3℃. The boiling point is 130.6℃, 23～24℃ (1.333×103Pa). The refractive index is 1.4366. The flash point is 30℃. It is insoluble in water, but soluble in ethanol, ether and acetone. It has anesthetic properties at high concentrations. It can be obtained by oxidation of cyclopentanol. Or it can be obtained by heating adipic acid in the presence of barium hydroxide. Cyclopentanone is easy to polymerize, especially in the presence of acid. Under heating, the following dehydration reactions can be carried out to generate 2-cyclopentylidenecyclopentanone and 2′-cyclopentylidene-2-cyclopentylidenecyclopentanone respectively.