Also known as: Pauson-Khand cycloaddition
The Pauson-Khand reaction is an organic reaction used to convert an alkyne and alkene to a substituted cyclopentenone under an atmosphere of carbon monoxide and a dicobalt complex catalyst. This 2+2+1 cycloaddition reaction begins with the addition of the alkyne to the metal complex followed by ligand substitution of the alkene to expel a CO molecule. Alkene insertion follows and a subsequent CO insertion results in the formation of a carbonyl group. A series of reductive eliminations then yield the final cyclopentenone product and regenerates the cobalt catalyst.
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