Advanced Topic 846 of 1102 Organic Chemistry
Olefin Metathesis
Catalytic exchange of alkene substituents using ruthenium carbene catalysts.
In-depth explanation of Olefin Metathesis
Olefin metathesis is a catalytic reaction that exchanges the alkylidene groups between two alkenes, breaking and reforming carbon-carbon double bonds. It proceeds through metallacyclobutane intermediates formed with ruthenium carbene catalysts such as Grubbs catalysts or with molybdenum catalysts. Ring-closing metathesis is used to form rings, including large macrocycles, while ring-opening metathesis polymerization makes polymers. The 2005 Nobel Prize in Chemistry recognized the development of this method.
Going deeper: Olefin Metathesis
Key ideas: Redistribution of C=C bonds, catalysed by Grubbs (ruthenium) or Schrock (molybdenum) carbenes through a metallacyclobutane intermediate (Chauvin mechanism). Types: ring-closing (RCM, releasing ethene to give rings of 5 to 30 members), cross metathesis and ring-opening polymerisation (ROMP). Driven by loss of volatile ethene. Awarded the 2005 Nobel Prize.
Common mistakes and connections: Students think the double bond is broken by acid or radical routes; it proceeds via metal carbene. Another error is forgetting the by-product for RCM, usually ethene. Links to polymerization, natural product synthesis and organometallic catalysis.
Visualization of Olefin Metathesis
The metal carbene and an alkene form a four-membered metallacyclobutane that opens to swap alkylidene groups between alkenes. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Ring-closing metathesis of a diene with a Grubbs catalyst gives a cyclic alkene and releases ethene.
Frequently asked questions about Olefin Metathesis
What is Olefin Metathesis?
Catalytic exchange of alkene substituents using ruthenium carbene catalysts.
Is Olefin Metathesis a beginner, intermediate or advanced topic?
Olefin Metathesis is a advanced topic in Organic Chemistry. It builds on beginner and intermediate topics, so review those first if needed.
What should I learn before Olefin Metathesis?
Study these earlier topics in Organic Chemistry first: Pericyclic Reactions, Woodward-Hoffmann Rules, Cross-Coupling Reactions.
What comes after Olefin Metathesis?
The next topics in Organic Chemistry are Asymmetric Synthesis and Green Chemistry Principles.
Can I practise Olefin Metathesis with quizzes?
Yes. The interactive lesson includes a self-check question on Olefin Metathesis, and the Organic Chemistry quiz draws on every topic in this area.
Where Olefin Metathesis fits in Organic Chemistry
Olefin Metathesis is topic 118 of 148 in Organic Chemistry.