Olefin Metathesis

2 R–CH=CH–R' ⇌ R–CH=CH–R + R'–CH=CH–R'

Overview

Olefin metathesis exchanges substituents around carbon-carbon double bonds using a ruthenium or molybdenum carbene catalyst. The mechanism involves [2+2] cycloaddition to form a metallacyclobutane, followed by cycloreversion. Chauvin, Grubbs, and Schrock shared the 2005 Nobel Prize for this reaction.

Everyday Example

Ring-closing metathesis is used to produce macrocyclic drug molecules like the hepatitis C drug simeprevir.

Industrial Importance

Shell's SHOP process uses cross-metathesis to produce alpha-olefins for detergents. Metathesis is transforming pharmaceutical synthesis.

Properties

Type: Organic
Reversible: Yes
Energy: Exothermic
ΔH: -5.0 kJ/mol
Catalyst: Grubbs catalyst (Ru-based)

Related Reactions

Aldol Condensation of Acetaldehyde Amide Formation (Acetic Acid + Ammonia) Baeyer-Villiger Oxidation Beckmann Rearrangement (Cyclohexanone Oxime) Bromination of Ethylene Buchwald-Hartwig Amination Cannizzaro Reaction of Formaldehyde Catalytic Hydrogenation of Ethylene Claisen Condensation (Ethyl Acetate) Condensation Polymerization (Nylon 6,6)

Frequently Asked Questions

What is the equation for Olefin Metathesis?

The balanced equation is: 2 R–CH=CH–R' ⇌ R–CH=CH–R + R'–CH=CH–R'.

What type of reaction is Olefin Metathesis?

Olefin Metathesis is a organic reaction. It is reversible under certain conditions.

Is Olefin Metathesis exothermic or endothermic?

Olefin Metathesis is exothermic (releases energy). The enthalpy change (ΔH) is -5.0 kJ/mol.

What conditions are needed for Olefin Metathesis?

This reaction requires a catalyst (Grubbs catalyst (Ru-based)).