Olefincontaining

Olefin-containing refers to chemical compounds that bear one or more carbon–carbon double bonds. The term emphasizes unsaturation and the chemical reactivity associated with C=C bonds, which distinguish these molecules from fully saturated hydrocarbons. Olefins occur across simple feedstocks, natural products, and functionalized compounds, ranging from small molecules such as ethene and propene to internal and conjugated alkenes like trans-2-butene, 1,3-butadiene, and isoprene. They may appear as pure hydrocarbons or as substructures within larger molecules such as polymers, terpenes, or pharmaceuticals.

Structural features of olefin-containing compounds include terminal (monosubstituted) and internal alkenes, as well as conjugated or isolated double bonds. The geometry of an alkene (cis or trans) can influence physical properties and reactivity. Conjugated olefins often display distinct spectroscopic behavior and reactivity patterns compared with nonconjugated ones.

Characterization and properties: the carbon–carbon double bond imparts characteristic signals in spectroscopy. Infrared spectroscopy shows C=C stretches around 1640–1680 cm−1, while nuclear magnetic resonance reveals vinylic protons typically in the 4.5–6.5 ppm range. Conjugation can shift absorption in UV–visible spectra. The presence of a double bond also makes these molecules reactive toward additions, oxidations, and polymerization, while leaving the possibility of remaining unsaturation for further functionalization in polymers.

Reactions and applications: olefins undergo a wide range of additions (hydrogenation, halogenation, hydrofunctionalization), oxidation to epoxides or carbonyls, and ozonolysis. They are central to polymer chemistry, serving as monomers for polyethylene, polypropylene (through various polymerization mechanisms), and other plastics; residual or pendant double bonds enable crosslinking and curing. Olefin metathesis enables strategic rearrangement of alkene fragments, expanding synthetic routes. Safety and handling considerations reflect typical flammability and reactivity of unsaturated hydrocarbons.