Metathesis

About: Metathesis is a research topic. Over the lifetime, 9246 publications have been published within this topic receiving 250828 citations.

Olefin Metathesis and Beyond

Abstract: The advent of well-defined catalysts for olefin metathesis which combine high activity, durability, and excellent tolerance towards polar functional groups has revolutionized the field. The past decade has seen the rapid embrace of these reagents as tools for advanced organic and polymer chemistry and the success of this development is witnessed by a plethora of elegant applications to the synthesis of natural and nonnatural products. This review article provides an overview of these developments and intends to familiarize the reader with some very recent advances which hold the promise to expand the scope of the reaction even further. Moreover, the positive impact of metathesis on the fundamental logic of retrosynthetic planning is demonstrated by means of typical examples. Finally, it will be shown that metathesis is by no means restricted to alkenes as substrates, and some comments on metathesis reactions following unconventional mechanistic pathways will also be presented.

Handbook of metathesis

Abstract: Preface.CATALYST DEVELOPMENTS.Introduction.The Role of the "Tebbe Complex" in Olefin Metathesis.The Discovery and Development of High Oxidation State Mo and W Imido Alkylidene Complexes for Alkene Metathesis.From ill-defined to well-defined W alkylidene complexes.Discovery of Well-defined Ruthenium Olefin Metathesis Catalysts.Synthesis of Ruthenium Carbene Complexes.ynthesis of Rhodium and Ruthenium Carbene Complexes with a 16-Electron Count.Mechanism of Ruthenium-Catalyzed Olefin Metathesis Reactions.Intrinsic Reactivity of Ruthenium Carbenes.The Discovery and Development of High Oxidation State Alkylidyne Complexes for Alkyne Metathesis.Well-defined Metallocarbenes and Metallocarbynes Supported on Oxide Support prepared via Surface Organometallic Chemistry.APPLICATIONS IN ORGANIC SYNTHESIS.Introduction.General Ring-Closing Metathesis.Catalytic Asymmetric Olefin Metathesis.Tandem RCM.Ene-Yne Metathesis.Ring Opening Cross Metathesis.Ring Expansion Metathesis Reactions.Olefin Cross-Metathesis.The Olefin Metathesis Reaction in Complex Molecule Construction.Applications of Ring Closing Metathesis to Alkaloid Synthesis.Radicicol and the Epothilones: Total Synthesis of Novel Anti Cancer Agents Using Ring Closing Metathesis.The Use of Olefin Metathesis in Combinatorial Chemistry: Supported and Chromatography-Free Syntheses.Metal-Catalyzed Olefin Metathesis in Metal Coordination Spheres.Alkyne Metathesis.Metathesis of silicon-containing olefins.Commercial Applications of Ruthenium Metathesis Processes.POLYMER SYNTHESIS.Introduction.Living Ring-Opening Olefin Metathesis Polymerization.Synthesis of Copolymers.Conjugated polymers.Stereochemistry of ROMP.Syntheses and Applications of Bioactive Polymers Generated by the Ring-Opening Metathesis Polymerization (ROMP).Metathesis Polymerization: A Versatile Tool for the Synthesis of Surface-Functionalized Supports and Monolithic Materials.Telechelic Polymers from Olefin Metathesis Methodologies.ADMET Polymerization.Acyclic Diyne Metathesis Utilizing in Situ Transition Metal Catalysts: An Efficient Access to Alkyne-Bridged Polymers.Polymerization of Substituted Acetylenes.Commercial Applications.

A General Model for Selectivity in Olefin Cross Metathesis

Abstract: In recent years, olefin cross metathesis (CM) has emerged as a powerful and convenient synthetic technique in organic chemistry; however, as a general synthetic method, CM has been limited by the lack of predictability in product selectivity and stereoselectivity. Investigations into olefin cross metathesis with several classes of olefins, including substituted and functionalized styrenes, secondary allylic alcohols, tertiary allylic alcohols, and olefins with α-quaternary centers, have led to a general model useful for the prediction of product selectivity and stereoselectivity in cross metathesis. As a general ranking of olefin reactivity in CM, olefins can be categorized by their relative abilities to undergo homodimerization via cross metathesis and the susceptibility of their homodimers toward secondary metathesis reactions. When an olefin of high reactivity is reacted with an olefin of lower reactivity (sterically bulky, electron-deficient, etc.), selective cross metathesis can be achieved using fee...

Molybdenum and tungsten imido alkylidene complexes as efficient olefin-metathesis catalysts.

Abstract: Catalytic olefin metathesis has quickly emerged as one of the most often-used transformations in modern chemical synthesis. One class of catalysts that has led the way to this significant development are the high-oxidation-state alkylidene complexes of molybdenum. In this review key observations that resulted in the discovery and development of molybdenum- and tungsten-based metathesis catalysts are outlined. An account of the utility of molybdenum catalysts in the synthesis of biologically significant molecules is provided as well. Another focus of the review is the use of chiral molybdenum complexes for enantioselective synthesis. These highly efficient catalysts provide unique access to materials of exceptional enantiomeric purity and often without generating solvent waste.