Olefin metathesis

Olefin metathesis or transalkylidenation (in some literature, a disproportionation) is an organic reaction which involves redistribution of olefinic (alkene) bonds. Since its discovery, olefin metathesis has gained widespread use in research and industry for making products ranging from medicines and polymers to enhanced fuels. Its advantages include the creation of fewer sideproducts and hazardous wastes. Yves Chauvin, Robert H. Grubbs, Richard R. Schrock shared the 2005 Nobel Prize in Chemistry for "the development of the metathesis method in organic synthesis".

Overview

One basic example is the cyclodimerization of ethylene 1 to cyclobutane 2 by a triphenylphosphine nickel catalyst.

Related Topics:
Ethylene - Cyclobutane - Triphenylphosphine

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Olefin metathesis was first used in petroleum reformation for the synthesis of higher olefins in the Shell higher olefin process (SHOP) under high pressure and high temperatures. Many traditional catalysts are derived from a reaction of the metal halides with alkylation agents for example WCl6-EtOH-EtAlCl2. A metathesis reaction is a chain reaction involving a metal-carbene. This carbene reacts with a olefine to a metallacyclobutane intermediate.

Related Topics:
Petroleum - Shell higher olefin process - Carbene

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A metal carbene based on ruthenium is Grubbs' Catalyst{{ref|dragutan}}, a Schrock carbene is a molybdenum catalyst.

Related Topics:
Grubbs' Catalyst - Schrock carbene

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