Light‐Driven <i>gem</i> Hydrogenation: An Orthogonal Entry into “Second‐Generation” Ruthenium Carbene Catalysts for Olefin Metathesis
Raphael J. Zachmann, Alois Fürstner
Abstract
The newly discovered light-driven gem hydrogenation of alkynes opens an unconventional yet efficient entry into five-coordinate Grubbs-type ruthenium carbene complexes with cis-disposed chloride ligands. Representatives of this class featuring a chelate substructure formed by an iodo-substituted benzylidene unit react with (substituted) 2-isopropoxystyrene to give prototypical "second-generation" Grubbs-Hoveyda complexes for olefin metathesis. The new approach to this venerable catalyst family is safe and versatile as it uses a triple bond rather than phenyldiazomethane as the ultimate carbene source and does not require any sacrificial phosphines.
Topics & Concepts
CarbeneRutheniumMetathesisOlefin metathesisTransition metal carbene complexCatalysisAcyclic diene metathesisChemistryOlefin fiberSalt metathesis reactionCombinatorial chemistryOrganic chemistryPolymerizationPolymerSynthetic Organic Chemistry MethodsCatalytic Cross-Coupling ReactionsCyclopropane Reaction Mechanisms