From Environmentally Friendly Reusable Ionic-Tagged Ruthenium-Based Complexes to Industrially Relevant Homogeneous Catalysts: Toward a Sustainable Olefin Metathesis
Abstract
This account describes our investigations, over the past decade, on the design of ruthenium-based complexes dedicated to sustainable olefin metathesis. An overview of different classes of catalysts, from reusable ionically tagged systems to industrially relevant homogeneous complexes, including latent catalysts, is disclosed. Challenging applications involving these robust complexes, including the valorization of olefin feedstock derived from biomass into valuable building blocks, are also discussed. 1 Introduction 2 Reusable Ionically Tagged Ruthenium Complexes for Olefin Metathesis in RTILs and Related SILP Processes 2.1 The First Generation: Olefin Metathesis in [BMIM]PF6 2.2 The Second Generation: Olefin Metathesis in Biphasic [BMIM]PF6/ Toluene Medium 2.3 Initiation Rates Versus Recyclability: The Linker Choice 2.4 Modulation of the NHC Unit: Toward the Optimum Reusable Catalytic System 2.5 Introduction of Aminocarbonyl-Based Linkers 2.6 The SILP Technology: Toward Olefin Metathesis in Continuous Flow 2.7 Catalysts Bearing an Ionically Tagged NHC Ligand 3 Structural Modifications Around the Styrenyl Ether Ligand for the Control of Initiation Rates: Toward a Library of Industrially Relevant Homogeneous Hoveyda-Type Complexes 3.1 Aminocarbonyl-Functionalized Complexes (M7) 3.1.1 Industrial-Scale Production of Complexes M71-SIPr and M73-SIPr 3.2 Aminosulfonyl-Tagged Ruthenium Complexes 3.3 Oxazine- and Oxazinone-Functionalized Ruthenium Complexes 3.4 Synthetic Applications 3.4.1 Production of High Added-Value Molecules 3.4.2 Valorization of Bio-Sourced Molecules 4 Ruthenium Complexes Bearing Unsymmetrical Cycloalkyl-NHCs: Efficient and Selective Catalysts for the Metathesis of α-Olefins 4.1 A Low-Cost Synthetic Route: The Arduengo Process Revisited Providing Unsymmetrical Unsaturated (U2)-NHCs and their Corresponding Ruthenium Complexes 4.2 Application in the Selective Metathesis of α-Olefins from Bio-Sourced Fischer-Tropsch Feeds 5 Design of Latent Ruthenium Complexes 5.1 A 'Dormant' Catalyst Bearing a Chelating Carboxylate Ligand 5.2 Ruthenium-Indenylidene Catalysts Bearing a Bidentate Picolinate Ligand 5.3 Serendipitous Discovery of Cationic Bis-NHC Hoveyda-Type Complexes 6 Conclusions and Outlook. © Georg Thieme Verlag Stuttgart · New York.