scholarly journals In tandem or alone: a remarkably selective transfer hydrogenation of alkenes catalyzed by ruthenium olefin metathesis catalysts

2015 ◽  
Vol 13 (9) ◽  
pp. 2684-2688 ◽  
Author(s):  
Grzegorz Krzysztof Zieliński ◽  
Cezary Samojłowicz ◽  
Tomasz Wdowik ◽  
Karol Grela
Keyword(s):  
Olefin Metathesis ◽  
Transfer Hydrogenation ◽  
Selective Transfer ◽  
Metathesis Reaction ◽  
Metathesis Catalyst ◽  
Selective System ◽  
Metathesis Catalysts

A remarkably selective system for transfer hydrogenation of alkenes, composed of Grubbs’ ruthenium metathesis catalyst and HCOONa/HCOOH, is presented. This system can also be formed directly after a metathesis reaction to effect hydrogenation in a single-pot.

ChemInform Abstract: In Tandem or Alone: A Remarkably Selective Transfer Hydrogenation of Alkenes Catalyzed by Ruthenium Olefin Metathesis Catalysts.

ChemInform ◽  
2015 ◽  
Vol 46 (26) ◽  
pp. no-no
Author(s):  
Grzegorz Krzysztof Zielinski ◽  
Cezary Samojlowicz ◽  
Tomasz Wdowik ◽  
Karol Grela
Keyword(s):  
Olefin Metathesis ◽  
Transfer Hydrogenation ◽  
Selective Transfer ◽  
Metathesis Catalysts

Quest for the ideal olefin metathesis catalyst

2008 ◽  
Vol 80 (1) ◽  
pp. 31-43 ◽  
Author(s):  
Anna Michrowska ◽  
Karol Grela
Keyword(s):  
Oxygen Atom ◽  
Quaternary Ammonium ◽  
Olefin Metathesis ◽  
Amino Group ◽  
Sulfonated Polystyrene ◽  
Grubbs Catalyst ◽  
Metathesis Catalyst ◽  
Metathesis Catalysts ◽  
Novel Strategy ◽  
The Ideal

Attempts were made to create a catalyst that approaches Gladysz's vision of an "ideal catalyst". Modifications of the Hoveyda-Grubbs catalyst were carried out with the aim to increase its activity and broaden the scope of its applicability to challenging metathesis reactions. This was done by introduction of an electron-withdrawing substituent on the isopropoxybenzylidene group in order to diminish the donor properties of the oxygen atom. The resulting stable and easily accessible nitro-substituted Hoveyda-Grubbs catalyst has found a number of successful applications in various research and industrial laboratories. Also, a new concept for noncovalent immobilization of a ruthenium olefin metathesis catalyst is presented. The 2-isopropoxybenzylidene ligand of Hoveyda-Grubbs carbene is further modified by an additional amino group, and immobilization is achieved by treatment with sulfonated polystyrene, forming the corresponding ammonium salt. In this novel strategy for the immobilization of ruthenium-based metathesis catalysts, the amino group plays a dual role, being first an active anchor for immobilization and secondly, after protonation, activating the catalysts by electron-donating to -withdrawing switch. The same concept has been used in the preparation of a quaternary ammonium catalyst for aqueous olefin metathesis.

scholarly journals Preparation of Ruthenium Olefin Metathesis Catalysts Immobilized on MOF, SBA-15, and 13X for Probing Heterogeneous Boomerang Effect

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 438 ◽  
Author(s):  
Artur Chołuj ◽  
Wojciech Nogaś ◽  
Michał Patrzałek ◽  
Paweł Krzesiński ◽  
Michał J. Chmielewski ◽  
...  
Keyword(s):  
Olefin Metathesis ◽  
Metal Organic Framework ◽  
Chemical Production ◽  
Metathesis Reaction ◽  
Solid Supports ◽  
13X Zeolite ◽  
Boomerang Effect ◽  
Metal Organic ◽  
Metathesis Catalysts ◽  
First Time

Promoted by homogeneous Ru-benzylidene complexes, the olefin metathesis reaction is a powerful methodology for C-C double bonds formation that can find a number of applications in green chemical production. A set of heterogeneous olefin metathesis pre-catalysts composed of ammonium-tagged Ru-benzylidene complexes 4 (commercial FixCat™ catalyst) and 6 (in-house made) immobilized on solid supports such as 13X zeolite, metal-organic framework (MOF), and SBA-15 silica were obtained and tested in catalysis. These hybrid materials were doped with various amounts of ammonium-tagged styrene derivative 5—a precursor of a spare benzylidene ligand—in order to enhance pre-catalyst regeneration via the so-called release-return “boomerang effect”. Although this effect was for the first time observed inside the solid support, we discovered that non-doped systems gave better results in terms of the resulting turnover number (TON) values, and the most productive were hybrid catalysts composed of 4@MOF, 4@SBA-15, and 6@SBA-15.

scholarly journals MOF Encapsulation of Ru Olefin Metathesis Catalysts to Block Catalyst Decomposition

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 687
Author(s):  
Gerard Pareras ◽  
Davide Tiana ◽  
Albert Poater
Keyword(s):  
Olefin Metathesis ◽  
Density Functional ◽  
Metal Organic Framework ◽  
Functional Theory ◽  
Ammonium N ◽  
Metathesis Catalyst ◽  
Metal Organic ◽  
Non Covalent Interactions ◽  
Metathesis Catalysts

In the present work, a catalyst variation of the second-generation Hoveyda–Grubbs catalyst, particularly the ammonium-tagged Ru-alkylidene metathesis catalyst AquaMetTM, is under study, not simply to increase the efficiency in olefin metathesis but also the solubility in polar solvents. Moreover, this ionic catalyst was combined with the metal organic framework (MOF) (Cr)MIL-101-SO3−(Na·15-crown-5)+. We started from the experimental results by Grela et al., who increased the performance when the ruthenium catalyst was confined inside the cavities of the MOF, achieving non-covalent interactions between both moieties. Here, using density functional theory (DFT) calculations, the role of the ammonium N-heterocyclic carbene (NHC) tagged and the confinement effects are checked. The kinetics are used to compare reaction profiles, whereas SambVca steric maps and NCI plots are used to characterize the role of the MOF structurally and electronically.

Vortex Fluidic Ethenolysis, Integrating a Rapid Quench of Ruthenium Olefin Metathesis Catalysts

2020 ◽  
Vol 73 (12) ◽  
pp. 1138
Author(s):  
Scott J. Pye ◽  
Justin M. Chalker ◽  
Colin L. Raston
Keyword(s):  
Thin Film ◽  
Olefin Metathesis ◽  
Continuous Flow ◽  
Rapid Quenching ◽  
Flow Process ◽  
Rapid Quench ◽  
Metathesis Catalyst ◽  
Fluidic Device ◽  
Continuous Flow Process ◽  
Metathesis Catalysts

Ruthenium-catalysed ethenolysis occurs in a vortex fluidic device (VFD) – a scalable, thin-film microfluidic continuous flow process. This process takes advantage of the efficient mass transfer of gaseous reagents into the dynamic thin film of liquid. Also reported is the rapid quenching of the ruthenium-based olefin metathesis catalyst by the addition of a saturated solution of N-acetyl-l-cysteine in MeCN, as a convenient alternative to previously reported quenching methods.

scholarly journals Decomposition of Ruthenium Olefin Metathesis Catalyst

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 887
Author(s):  
Magdalena Jawiczuk ◽  
Anna Marczyk ◽  
Bartosz Trzaskowski
Keyword(s):  
Olefin Metathesis ◽  
Decomposition Rates ◽  
Detailed Review ◽  
Mechanism Of Decomposition ◽  
External Agents ◽  
Metathesis Catalyst ◽  
Metathesis Catalysts

Ruthenium olefin metathesis catalysts are one of the most commonly used class of catalysts. There are multiple reviews on their uses in various branches of chemistry and other sciences but a detailed review of their decomposition is missing, despite a large number of recent and important advances in this field. In particular, in the last five years several new mechanism of decomposition, both olefin-driven as well as induced by external agents, have been suggested and used to explain differences in the decomposition rates and the metathesis activities of both standard, N-heterocyclic carbene-based systems and the recently developed cyclic alkyl amino carbene-containing complexes. Here we present a review which explores the last 30 years of the decomposition studied on ruthenium olefin metathesis catalyst driven by both intrinsic features of such catalysts as well as external chemicals.

Olefin Metathesis: Catalyst Development, Microwave Catalysis, and Domino Applications

2005 ◽  
Vol 58 (1) ◽  
pp. 3 ◽  
Author(s):  
Steven G. Aitken ◽  
Andrew D. Abell
Keyword(s):  
Olefin Metathesis ◽  
Historical Development ◽  
Metathesis Reaction ◽  
Reaction Conditions ◽  
Catalyst Development ◽  
Metathesis Catalyst ◽  
Convenient Route ◽  
The Way

Olefin metathesis, a process by which alkylidene groups on alkenes are exchanged, is reviewed with reference to the historical development of functional catalysts and microwave catalysis. The advent of new catalysts and improved reaction conditions has paved the way for the development of new and versatile domino processes that combine either different metathesis events or a key metathesis reaction with another reaction in a particularly atom economic and ‘green’ sense. We review this area as a convenient route to some otherwise difficult to prepare systems.

scholarly journals The activity of indenylidene derivatives in olefin metathesis catalysts

2018 ◽  
Vol 14 ◽  
pp. 2956-2963 ◽  
Author(s):  
Maria Voccia ◽  
Steven P Nolan ◽  
Luigi Cavallo ◽  
Albert Poater
Keyword(s):  
Olefin Metathesis ◽  
Density Functional ◽  
Bond Orders ◽  
Metathesis Reaction ◽  
Functional Theory ◽  
New Family ◽  
Sterically Demanding ◽  
Electronic Parameters ◽  
Metathesis Catalysts ◽  
Dissociation Step

The first turnover event of an olefin metathesis reaction using a new family of homogenous Ru-based catalysts bearing modified indenylidene ligands has been investigated, using methoxyethylene as a substrate. The study is carried out by means of density functional theory (DFT). The indenylidene ligands are decorated with ortho-methyl and isopropyl groups at both ortho positions of their phenyl ring. DFT results highlight the more sterically demanding indenylidenes have to undergo a more exothermic first phosphine dissociation step. Overall, the study emphasises advantages of increased steric hindrance in promoting the phosphine release, and the relative stability of the corresponding metallacycle over classical ylidene ligands. Mayer bond orders and steric maps provide structural reasons for these effects, whereas NICS aromaticity and conceptual DFT confirm that the electronic parameters do not play a significant role.

Sign in / Sign up

Export Citation Format

Share Document