Pauson‐Khand Reaction

Abstract

The dicobalt octacarbonyl [Co 2 (CO) 8 ] mediated or promoted one‐step synthesis of α,β‐unsaturated cyclopentenone from the [2+2+1] cycloaddition of alkyne, alkene and carbon monoxide, through an intermediate of alkynedicobalt hexacarbonyl complex is generally known as the Pauson–Khand reaction. For the purpose of stereochemical control, many Pauson–Khand reactions have been designed as intramolecular reactions or using cyclic alkenes, such as norbornene. This reaction has some drawbacks and the original protocol of the Pauson–Khand reaction has been extensively modified by the use of different catalysts or reaction conditions. The study finds that besides Co 2 (CO) 8 , many other transition metal complexes are effective for promoting this reaction. This reaction has wide application in organic synthesis.