Cyclopentadiene and Dicyclopentadiene

Abstract Cyclopentadiene is the most widely studied, conjugated cyclodiene in the history of organic chemistry. The more stable form, dicyclopentadiene, has a multitude of applications. This article discusses the physical properties of these compounds, chemical reactions, derivatives, manufacturing processes, and applications. Cyclopentadiene undergoes the Diels‐Alder reaction with itself and with a wide variety of olefins and diolefins. In addition, it can be functionalized to many derivatives and can be polymerized with itself and other olefins. The derivatives are used in polyesters, perfumes, elastomers, and pesticides. Metallocene complexes of cyclopentadiene have been extensively studied and are useful as catalysts. Dicyclopentadiene is used in polymers with itself and with other hydrocarbons, in polyester resins, bodied oils, elastomers, polycarbonates, and pharmaceuticals. Total worldwide recoverable dicyclopentadiene capacity exceeds 175,000 metric tons per year.