Six new ruthenium complexes bearing a bidentate (κ(2)O,C)-isopropoxy-indenylidene and PPh(3) or PCy(3) ligands have been synthesized and characterized by (1)H, (13)C NMR spectroscopy and X-ray crystallography. Some of these complexes were synthesized in dimethyl carbonate, a green solvent that was recently shown to be suitable for several catalytic transformations including olefin metathesis. The thermal stability and catalytic efficiency of the PCy(3)-containing complexes have been evaluated in a series of test reactions.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c2dt12271e | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Depolymerization of vulcanized poly(cyclopentene), poly(norbornene--cyclopentene) and poly(-dicyclopentadiene--cyclopentene) rubbers ring-closing metathesis depolymerization for monomer recycling.
RSC Adv
November 2024
Zeon Corporation R&D Center 1-2-1 Yako, Kawasaki-ward Kawasaki-city Kanagawa-pref. 210-9507 Japan +81-44-276-3957 +81-80-1006-7136.
Herein, we report a study on the preparation, properties, and depolymerization of pristine and vulcanized poly(cyclopentene) (poly(CP)), poly(norbornene--cyclopentene) (poly(NB--CP)) and poly(-dicyclopentadiene--cyclopentene) (poly (DCP--CP)). First, poly(CP), poly(NB--CP) and poly(DCP--CP) were prepared with high molecular weight control ( = 200 000-500 000) using dichloro(3-phenyl-1-inden-1-ylidene)bis(tricyclohexylphosphine)ruthenium(ii). Next, carbon black, zinc oxide and other additives were blended into the pristine polymers using a mixer and twin roll rubber mills at 50 °C, followed by vulcanization in metal molds at 160 °C for 10 min, resulting in molded black rubber specimens.
View Article and Find Full Text PDFB(CF) Co-Catalyst Promotes Unconventional Halide Abstraction from Grubbs I to Enhance Reactivity and Limit Decomposition.
Organometallics
November 2024
Department of Chemistry and Biochemistry, Old Dominion University, 4501 Elkhorn Avenue, Norfolk, Virginia 23529, United States.
Ruthenium based Grubbs metathesis has become a commonplace reaction for synthetic chemists. Development of new generations of catalysts evolving from Grubbs I (GI) have led to greater stability, functional group compatibility, and superior reactivities. However, these advancements lead to increased costs.
View Article and Find Full Text PDFThe Tetrafluoroethylene-Mediated Ring-Closing Metathesis: Enabling Unfavored Reactions.
J Am Chem Soc
November 2024
Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Tokyo 113-0032, Japan.
While ring-closing metathesis (RCM) is a powerful method for constructing medium and large cyclic alkenes, its application to the synthesis of heterocycles faces considerable limitations. For instance, RCM of divinyloxyalkanes does not proceed under the conventional conditions of RCM. The challenge lies in the formation of stable Fischer-type carbene intermediates with heteroatom(s) bound to the carbene carbon, impeding subsequent metathesis.
View Article and Find Full Text PDFCatalytic Syntheses of Thiol-End-Functionalized ROMP Polymers.
ACS Macro Lett
December 2024
Department of Chemistry, University of Fribourg, CH-1700 Fribourg, Switzerland.
Article Synopsis
- Thiol-functionalized polymers are important due to their unique chemical properties and various applications, prompting research into their synthesis.
- The study details an easy method for creating thiol-end-functionalized polymers using ring-opening metathesis polymerization (ROMP) and catalytic mechanisms with chain transfer agents.
- Characterization techniques confirmed the successful synthesis and presence of thiol groups, potentially impacting materials science and biochemistry positively by using less ruthenium in the process.
Mechanistic Insights into the -Selective Catalytic Ring-Opening Metathesis Polymerization.
J Am Chem Soc
November 2024
Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
-selective ring-opening metathesis polymerization (ROMP) with the commercial Grubbs "nitrato catalyst" has shown promise for synthesizing stereoregular materials, but it comes with the drawback of losing control over the molecular weight due to the poor initiation rate of the catalyst and the need for stoichiometric ruthenium complex loading. To address these issues, we developed a chain transfer polymerization method that allows for the catalytic synthesis of polymers while controlling the degree of polymerization. This allowed us to produce shorter polymers with exceptional chain-end control.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!