olefiinin

Olefiinin is a term historically used to refer to alkenes, which are unsaturated hydrocarbons containing at least one carbon-carbon double bond. The name "olefiin" originates from the Latin phrase "oleum pabulum," meaning "oil-producing food," due to the tendency of early discovered alkenes, like ethylene, to react with halogens to form oily liquids. While the term "alkene" is now the standard and preferred nomenclature in modern organic chemistry, "olefiin" may still be encountered in older literature or certain industrial contexts.

The defining characteristic of an olefiin is the presence of a pi bond within the carbon-carbon double bond. This pi bond is weaker than the sigma bond and is more accessible for chemical reactions, making alkenes highly reactive. Common reactions involving olefiins include addition reactions, such as halogenation, hydrohalogenation, hydration, and hydrogenation. These reactions are fundamental to many synthetic processes.

Ethylene (ethene) is the simplest olefiin and a crucial industrial chemical, serving as a building block for polymers like polyethylene, a widely used plastic. Propylene (propene) is another important olefiin, used in the production of polypropylene and other chemicals. The study and understanding of olefiins have been central to the development of organic chemistry and the petrochemical industry.