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Updated: Jun 20, 2026

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Chemodivergent metathesis of dienynes catalyzed by ruthenium-indenylidene complexes: an experimental and
Hervé Clavier1, Andrea Correa, Eduardo C Escudero-Adán
1School of Chemistry, University of St-Andrews, North Haugh, St Andrews, KY16 9ST, UK.
Abstract:
A study on the enyne metathesis reaction leading to the formation cyclic compounds using ruthenium-indenylidene complexes is presented. Several 1,11-dien-6-ynes have been subjected to ruthenium metathesis cyclization by using ruthenium-indenylidene complexes bearing various phosphine and N-heterocyclic carbene (NHC) ligands. Interestingly, for some substrates chemodivergent metathesis occurs and is a function of the catalyst employed. This led us to investigate the competing "ene-then-yne" or "yne-then-ene" reaction pathways apparently at play in these systems using both experimental observations and DFT calculations. Experimental and computational studies were found in good agreement and permit to conclude that for phosphine-containing catalysts, the "ene-then-yne" pathway is exclusively adopted. On the other hand, for catalysts bearing NHC ligands, both pathways are possible.
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