Grubbs' Catalyst

Grubbs' Catalyst is named after the chemist by whom it was first synthesized, Robert H. Grubbs. There are two generations of the catalyst, as shown on the right. In contrast to other olefin metathesis catalysts, Grubbs' Catalysts tolerate other functional groups in the alkene and are compatible with a wide range of solvents4. For these reasons, Grubbs' Catalysts are extraordinarily versatile.

Related Topics:
Robert H. Grubbs - Olefin metathesis - Functional groups - Alkene

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The 1st Generation Catalyst is often used in organic synthesis to achieve olefin cross-metathesis (see below), ring-opening metathesis polymerization (ROMP), and ring-closing metathesis2. It is easily synthesized from RuCl2(PPh3)3, phenyldiazomethane, and tricyclohexylphosphine in a one-pot synthesis 1. Grubbs' Catalyst is a relatively stable compound in air, which makes handling very easy. The IUPAC name of the 1st Generation Catalyst is benzylidene-bis(tricyclohexylphosphine)dichlororuthenium.

Related Topics:
Catalyst - Organic synthesis - Olefin cross-metathesis - Ring-opening metathesis polymerization - Ring-closing metathesis - Phenyldiazomethane - One-pot synthesis - IUPAC

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Olefin metathesis, shown below, is a reaction between two molecules containing double bonds. The groups bonded to the carbon atoms of the double bond are exchanged between molecules, to produce two new molecules containing double bonds with swapped groups. Whether a cis or trans isomer is formed in this type of reaction is determined by the orientation the molecules assume when they coordinate to the catalyst, as well as the sterics of the substituents on the double bond of the newly forming molecule. Other catalysts are effective for this reaction, notably those developed by Richard R. Schrock (Schrock carbene).

Related Topics:
Olefin metathesis - Cis - Trans - Isomer - Sterics - Substituent - Richard R. Schrock - Schrock carbene

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The Second Generation Catalyst has the same uses in organic synthesis as the First Generation Catalyst, but has a higher activity. This catalyst is also air stable and is easily synthesized from the combination of the 1st Generation Catalyst and alkoxy-protected 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene3. The IUPAC name of the Second Generation Catalyst is benzylidenedichloro(tricyclohexylphosphine)ruthenium. Both generations of the catalyst are commercially available through Aldrich.

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An interesting application of Grubbs' Catalyst is in the aerospace industry. A spaceship's hull is a necessarily very strong material, but over time small microcracks in the structure can form. A new material used in the construction of spaceship hulls contains Grubbs' Catalyst, as well as capsules of dicyclopentadiene, which can undergo ROMP. When a crack in the hull forms, the capsules are ruptured and come into contact with Grubbs' Catalyst, which polymerizes dicyclopentadiene and seals the crack5.

Related Topics:
Hull - Microcrack - Dicyclopentadiene - Polymerizes

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On October 5, 2005, Robert H. Grubbs, Richard R. Schrock and Yves Chauvin won the Nobel Prize in Chemistry in recognition of their contributions to the development of this widely used process.

Related Topics:
October 5 - 2005 - Robert H. Grubbs - Richard R. Schrock - Yves Chauvin - Nobel Prize in Chemistry

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