Pauson-Khand Reaction Mechanism, and Applications

Pauson-Khand Reaction, examples, mechanisms, and applications in organic chemistry have been discussed here:

Pauson-Khand Reaction

The ring formation reaction involves [2+2+1] cycloaddition between an alkyne, an alkene, and carbon monoxide to form α, β-cyclopentenone known as Pauson-Khand reaction. In other words, it is one step-synthesis α, β-unsaturated cyclopentenone from the [2+2+1] cycloaddition of alkyne, alkene, and carbon monoxide, via an intermediate of alkynedicobalt hexacarbonyl complex. Pauson-Khand reaction is also known as Pauson-Khand cyclization, Pauson-Khand cycloaddition, or Pauson-Khand annulation.

Several Pauson-Khand reactions are intended as intramolecular reactions in order to attain stereochemical control. In the case of intermolecular Pauson-Khand reaction, due to steric hindrance, an alkene is positioned next to the less bulky acetylenic substituent during coordination, and a subsequent C-C bond forms between an alkene carbon and the closer acetylenic carbon, leading to the formation of the larger group on alkyne being found at the α-position of the resulting cyclopentenone.

The Pauson-Khand reaction has also been performed under a variety of conditions, including the use of chiral ligands, aldehydes as a carbon monoxide source, solid-supported cobalt catalysts to improve purification, colloidal cobalt nanoparticles, and so on.

The pauson-Khand reaction can be represented as:

Pauson-khand reaction. pauson-khand reaction examples, pauson-khand reaction mechanism
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Pauson-Khand Reaction Mechanism

The mechanism of the Pauson-Khand reaction can be carried out in the following way:

Pauson-khand reaction mechanism, pauson-khand reaction, pauson-khand examples
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Applications of Pauson-Khand reaction

The Pauson–Khand reaction is commonly used to prepare cyclopentenones and their derivatives. This reaction also aids in the overall synthesis of a number of topologically complicated natural products with a variety of structural characteristics.

Pauson-Khand Reaction Video


What is Pauson-Khand reaction?

Pauson-Khand reaction is [2+2+1] cycloaddition between an alkyne, an alkene, and carbon monoxide to form α, β-cyclopentenone.

Uses of Pauson-Khand reaction

Pauson-Khand reaction is used to prepare cyclopentenone.


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