1
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Kinugawa T, Matsuo T. Reactivity regulation for olefin metathesis-catalyzing ruthenium complexes with sulfur atoms at the terminal of 2-alkoxybenzylidene ligands. Dalton Trans 2023. [PMID: 37368438 DOI: 10.1039/d3dt01471a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
For regulating the olefin metathesis (OM) activity of the Hoveyda-Grubbs second-generation complex (HG-II), the structural modification of the benzylidene ligand is a useful strategy. This paper reports the effect of a chalcogen atom placed at the end of the benzylidene group on the catalytic properties of HG-II derivatives, using complexes with a thioether or ether component in the benzylidene ligand (ortho-Me-E-(CH2)2O-styrene; E = S, O). Nuclear magnetic resonance and X-ray crystallographic analyses of the complex with a thioether moiety (E = S) proved the (O,S)-bidentate and trans-dichlorido coordination for the complex. A stoichiometric ligand exchange between HG-II and the benzylidene ligand (E = S) produced the corresponding complex with an 86% yield, confirming higher stability of the complex (E = S) than that of HG-II. Despite the bidentate chelation, the complex (E = S) exhibited OM catalytic activity, indicating the exchangeability of the S-chelating ligand with an olefinic substrate. The green solution color, a characteristic of HG-II derivatives, was retained after the complex (E = S)-mediated OM reactions, indicating high catalyst durability. Conversely, the complex (E = O) rapidly initiated OM reactions; however, it showed low catalyst durability. In the OM reactions conducted in the presence of methanol, the complex (E = S) exhibited higher yields than the complex (E = O) and HG-II: the S-coordination increased the catalyst tolerance to methanol. A coordinative atom (such as sulfur) placed at the terminal of the benzylidene ligand can precisely regulate the reactivity of HG-II derivatives.
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Affiliation(s)
- Tsubasa Kinugawa
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology (NAIST), Ikoma, Nara 630-0192, Japan.
| | - Takashi Matsuo
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology (NAIST), Ikoma, Nara 630-0192, Japan.
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2
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Thangavel M, Chin SY. Valorization of palm oil via cross-metathesis reaction using 1-octene. CHEM ENG COMMUN 2022. [DOI: 10.1080/00986445.2022.2111555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- M. Thangavel
- Department of Chemical Engineering, College of Engineering, University Malaysia Pahang, Gambang, Malaysia
| | - S. Y. Chin
- Department of Chemical Engineering, College of Engineering, University Malaysia Pahang, Gambang, Malaysia
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3
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Eivgi O, Phatake RS, Nechmad NB, Lemcoff NG. Light-Activated Olefin Metathesis: Catalyst Development, Synthesis, and Applications. Acc Chem Res 2020; 53:2456-2471. [PMID: 32990427 PMCID: PMC7584343 DOI: 10.1021/acs.accounts.0c00495] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Indexed: 12/30/2022]
Abstract
The most important means for tuning and improving a catalyst's properties is the delicate exchange of the ligand shell around the central metal atom. Perhaps for no other organometallic-catalyzed reaction is this statement more valid than for ruthenium-based olefin metathesis. Indeed, even the simple exchange of an oxygen atom for a sulfur atom in a chelated ruthenium benzylidene about a decade ago resulted in the development of extremely stable, photoactive catalysts. This Account presents our perspective on the development of dormant olefin metathesis catalysts that can be activated by external stimuli and, more specifically, the use of light as an attractive inducing agent.The insight gained from a deeper understanding of the properties of cis-dichlororuthenium benzylidenes opened the doorway for the systematic development of new and efficient light-activated olefin metathesis catalysts and catalytic chromatic-orthogonal synthetic schemes. Following this, ways to disrupt the ligand-to-metal bond to accelerate the isomerization process that produced the active precatalyst were actively pursued. Thus, we summarize herein the original thermal activation experiments and how they brought about the discoveries of photoactivation in the sulfur-chelated benzylidene family of catalysts. The specific wavelengths of light that were used to dissociate the sulfur-ruthenium bond allowed us to develop noncommutative catalytic chromatic-orthogonal processes and to combine other photochemical reactions with photoinduced olefin metathesis, including using external light-absorbing molecules as "sunscreens" to achieve novel selectivities. Alteration of the ligand sphere, including modifications of the N-heterocyclic carbene (NHC) ligand and the introduction of cyclic alkyl amino carbene (CAAC) ligands, produced more efficient light-induced activity and special chemical selectivity. The use of electron-rich sulfoxides and, more prominently, phosphites as the agents that induce latency widened the spectrum of light-induced olefin metathesis reactions even further by expanding the colors of light that may now be used to activate the catalysts, which can be used in applications such as stereolithography and 3D printing of tough metathesis-derived polymers.
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Affiliation(s)
- Or Eivgi
- Department
of Chemistry, Ben-Gurion University of the
Negev, Beer-Sheva 84105, Israel
| | - Ravindra S. Phatake
- Department
of Chemistry, Ben-Gurion University of the
Negev, Beer-Sheva 84105, Israel
| | - Noy B. Nechmad
- Department
of Chemistry, Ben-Gurion University of the
Negev, Beer-Sheva 84105, Israel
| | - N. Gabriel Lemcoff
- Department
of Chemistry, Ben-Gurion University of the
Negev, Beer-Sheva 84105, Israel
- Ilse
Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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4
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Planer S, Małecki P, Trzaskowski B, Kajetanowicz A, Grela K. Sterically Tuned N-Heterocyclic Carbene Ligands for the Efficient Formation of Hindered Products in Ru-Catalyzed Olefin Metathesis. ACS Catal 2020; 10:11394-11404. [PMID: 33123411 PMCID: PMC7587146 DOI: 10.1021/acscatal.0c02770] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 09/03/2020] [Indexed: 11/28/2022]
Abstract
Formation of tetrasubstituted C-C double bonds via olefin metathesis is considered very challenging for classical Ru-based complexes. In the hope to improve this condition, three ruthenium olefin metathesis catalysts bearing sterically reduced N-heterocyclic carbene (NHC) ligands with xylyl "arms" were synthesized, characterized using both computational and experimental techniques, and tested in a number of challenging reactions. The catalysts are predicted to initiate much faster than the analogue with mesityl N-substituents. We also foreboded the rotation of xylyl side groups at ambient temperature and the existence of all four atropoisomers in the solution, which was in agreement with experimental data. These catalysts exhibited high activity at relatively low temperatures (45-60 °C) and at reduced catalyst loadings in various reactions of sterically hindered alkenes, including complex polyfunctional substrates of pharmaceutical interest, such as yangonin precursors, chrysantemic acid derivatives, analogues of cannabinoid agonists, α-terpineol, and finally a thermally unstable peroxide.
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Affiliation(s)
- Sebastian Planer
- Biological
and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Paweł Małecki
- Biological
and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Bartosz Trzaskowski
- Centre
of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Anna Kajetanowicz
- Biological
and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Karol Grela
- Biological
and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
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5
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Pieczykolan M, Czaban-Jóźwiak J, Malinska M, Woźniak K, Dorta R, Rybicka A, Kajetanowicz A, Grela K. The Influence of Various N-Heterocyclic Carbene Ligands on Activity of Nitro-Activated Olefin Metathesis Catalysts. Molecules 2020; 25:E2282. [PMID: 32408688 PMCID: PMC7287594 DOI: 10.3390/molecules25102282] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/06/2020] [Accepted: 05/08/2020] [Indexed: 01/13/2023] Open
Abstract
A set of nitro-activated ruthenium-based Hoveyda-Grubbs type olefin metathesis catalysts bearing sterically modified N-hetero-cyclic carbene (NHC) ligands have been obtained, characterised and studied in a set of model metathesis reactions. It was found that catalysts bearing standard SIMes and SIPr ligands (4a and 4b) gave the best results in metathesis of substrates with more accessible C-C double bonds. At the same time, catalysts bearing engineered naphthyl-substituted NHC ligands (4d-e) exhibited high activity towards formation of tetrasubstituted C-C double bonds, the reaction which was traditionally Achilles' heel of the nitro-activated Hoveyda-Grubbs catalyst.
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Affiliation(s)
- Michał Pieczykolan
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland; (M.P.); (J.C.-J.)
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland; (M.M.); (K.W.); (A.R.)
| | - Justyna Czaban-Jóźwiak
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland; (M.P.); (J.C.-J.)
| | - Maura Malinska
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland; (M.M.); (K.W.); (A.R.)
| | - Krzysztof Woźniak
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland; (M.M.); (K.W.); (A.R.)
| | - Reto Dorta
- Department of Chemistry, School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Perth 6009, Australia;
| | - Anna Rybicka
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland; (M.M.); (K.W.); (A.R.)
| | - Anna Kajetanowicz
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland; (M.M.); (K.W.); (A.R.)
| | - Karol Grela
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland; (M.P.); (J.C.-J.)
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland; (M.M.); (K.W.); (A.R.)
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6
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Eivgi O, Vaisman A, Nechmad NB, Baranov M, Lemcoff NG. Latent Ruthenium Benzylidene Phosphite Complexes for Visible-Light-Induced Olefin Metathesis. ACS Catal 2019. [DOI: 10.1021/acscatal.9b05079] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Or Eivgi
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Anna Vaisman
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Noy B. Nechmad
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Mark Baranov
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - N. Gabriel Lemcoff
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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7
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Bousquet L, Nicholas KM. In search of alkene-diazene cross metathesis. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2019.120909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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8
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Bidal YD, Urbina-Blanco CA, Poater A, Cordes DB, Slawin AMZ, Cavallo L, Cazin CSJ. Electronic effects in mixed N-heterocyclic carbene/phosphite indenylidene ruthenium metathesis catalysts. Dalton Trans 2019; 48:11326-11337. [PMID: 31273362 DOI: 10.1039/c9dt01811e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Five new complexes [RuCl2(SIMes)(Ind)(O-pXC5H4)] bearing different para-substituted triphenylphosphites (X = H, OCH3, CF3, Cl, SF5 and CN) were synthesised and used to study the effect of the electronic properties of the phosphite on olefin metathesis activity. Investigations of the physical properties of the new ligands and complexes were performed using physicochemical and DFT calculations. The catalytic activity of the complexes was benchmarked in challenging ring closing metathesis transformations featuring the formation of tetra-substituted double bonds. Complex [RuCl2(SIMes)(Ind)P(O-pCF3C5H4)3] (3c) exhibited a particularly high catalytic activity, superior to state-of-the-art catalysts, and was further tested on a wide range of substrates.
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Affiliation(s)
- Yannick D Bidal
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - César A Urbina-Blanco
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK and Laboratory for Chemical Technology, Ghent University, Technologiepark 125, B-9052 Gent, Belgium
| | - Albert Poater
- Institut de Química Computacional i Catàlisi, Departament de Química, University of Girona, Girona 17003, Catalonia, Spain
| | - David B Cordes
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Alexandra M Z Slawin
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Luigi Cavallo
- KAUST Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Catherine S J Cazin
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK and Centre for Sustainable Chemistry, Department of Chemistry, Ghent University, Krijgslaan 281 - S3, 9000 Gent, Belgium.
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9
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Ageshina AA, Sterligov GK, Rzhevskiy SA, Topchiy MA, Chesnokov GA, Gribanov PS, Melnikova EK, Nechaev MS, Asachenko AF, Bermeshev MV. Mixed er-NHC/phosphine Pd(ii) complexes and their catalytic activity in the Buchwald–Hartwig reaction under solvent-free conditions. Dalton Trans 2019; 48:3447-3452. [DOI: 10.1039/c9dt00216b] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A single catalyst for solvent-free Buchwald–Hartwig amination with both primary and secondary amines.
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10
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Voccia M, Nolan SP, Cavallo L, Poater A. The activity of indenylidene derivatives in olefin metathesis catalysts. Beilstein J Org Chem 2018; 14:2956-2963. [PMID: 30546480 PMCID: PMC6278753 DOI: 10.3762/bjoc.14.275] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/15/2018] [Indexed: 12/26/2022] Open
Abstract
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.
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Affiliation(s)
- Maria Voccia
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, c/ Mª Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain
| | - Steven P Nolan
- Department of Chemistry and Center for Sustainable Chemistry, Ghent University, Krijgslaan 281, S-3, B-9000 Ghent, Belgium
- Department of Chemistry, College of Science King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Luigi Cavallo
- King Abdullah University of Science & Technology, KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia
| | - Albert Poater
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, c/ Mª Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain
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11
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Eivgi O, Guidone S, Frenklah A, Kozuch S, Goldberg I, Lemcoff NG. Photoactivation of Ruthenium Phosphite Complexes for Olefin Metathesis. ACS Catal 2018. [DOI: 10.1021/acscatal.8b01637] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Or Eivgi
- Department of Chemistry, Ben Gurion University of the Negev, Beer-Sheva, Israel, 84105
| | - Stefano Guidone
- Department of Chemistry, Ben Gurion University of the Negev, Beer-Sheva, Israel, 84105
| | - Alexander Frenklah
- Department of Chemistry, Ben Gurion University of the Negev, Beer-Sheva, Israel, 84105
| | - Sebastian Kozuch
- Department of Chemistry, Ben Gurion University of the Negev, Beer-Sheva, Israel, 84105
| | - Israel Goldberg
- School of Chemistry, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - N. Gabriel Lemcoff
- Department of Chemistry, Ben Gurion University of the Negev, Beer-Sheva, Israel, 84105
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel, 84105
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12
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Metathesis of renewable polyene feedstocks – Indirect evidences of the formation of catalytically active ruthenium allylidene species. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2017.04.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Robertson ID, Dean LM, Rudebusch GE, Sottos NR, White SR, Moore JS. Alkyl Phosphite Inhibitors for Frontal Ring-Opening Metathesis Polymerization Greatly Increase Pot Life. ACS Macro Lett 2017; 6:609-612. [PMID: 35650845 DOI: 10.1021/acsmacrolett.7b00270] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Frontal ring-opening metathesis polymerization (FROMP) has potential for use in rapid fabrication of structural polymers. However, the high activity of the ruthenium catalyst used for FROMP has limited the working time to <1 h. We report the use of alkyl phosphites as inhibitors for Grubbs' type catalysts to substantially extend working time. Subtle changes in alkyl phosphite structure are shown to impact both pot life and frontal velocity. Specifically, by varying phosphite structure and concentration, we are able to control pot life between 0.25 and 30 h while still allowing FROMP to proceed at velocities between 1 and 8 cm/min to yield fully cured thermoset polymers. These results are of interest for conventional ROMP synthesis and may open the way to new FROMP-based manufacturing possibilities.
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Affiliation(s)
- Ian D. Robertson
- Departments
of Chemistry, ‡Materials Science and Engineering, §Aerospace Engineering, and the ⊥Beckman
Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Leon M. Dean
- Departments
of Chemistry, ‡Materials Science and Engineering, §Aerospace Engineering, and the ⊥Beckman
Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Gabriel E. Rudebusch
- Departments
of Chemistry, ‡Materials Science and Engineering, §Aerospace Engineering, and the ⊥Beckman
Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Nancy R. Sottos
- Departments
of Chemistry, ‡Materials Science and Engineering, §Aerospace Engineering, and the ⊥Beckman
Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Scott R. White
- Departments
of Chemistry, ‡Materials Science and Engineering, §Aerospace Engineering, and the ⊥Beckman
Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Jeffrey S. Moore
- Departments
of Chemistry, ‡Materials Science and Engineering, §Aerospace Engineering, and the ⊥Beckman
Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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14
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Olefin Metathesis with Ru-Based Catalysts Exchanging the Typical N-Heterocyclic Carbenes by a Phosphine–Phosphonium Ylide. Catalysts 2017. [DOI: 10.3390/catal7030085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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15
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Mikus MS, Torker S, Xu C, Li B, Hoveyda AH. Pentacoordinate Ruthenium(II) Catecholthiolate and Mercaptophenolate Catalysts for Olefin Metathesis: Anionic Ligand Exchange and Ease of Initiation. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00773] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Malte S. Mikus
- Department of Chemistry,
Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Sebastian Torker
- Department of Chemistry,
Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Chaofan Xu
- Department of Chemistry,
Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Bo Li
- Department of Chemistry,
Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Amir H. Hoveyda
- Department of Chemistry,
Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
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16
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Balla Á, Al-Hashimi M, Hlil A, Bazzi HS, Tuba R. Ruthenium-Catalyzed Metathesis of Conjugated Polyenes. ChemCatChem 2016. [DOI: 10.1002/cctc.201600479] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Áron Balla
- Institute of Materials and Environmental Chemistry; Research Centre for Natural Sciences; Hungarian Academy of Sciences; Magyar tudósok körútja 2., P.O. Box 286 1519 Budapest Hungary
| | - Mohammed Al-Hashimi
- Department of Chemistry; Texas A&M University at Qatar; P.O. Box 23874 Doha Qatar
| | - Antisar Hlil
- Department of Chemistry; Texas A&M University at Qatar; P.O. Box 23874 Doha Qatar
| | - Hassan S. Bazzi
- Department of Chemistry; Texas A&M University at Qatar; P.O. Box 23874 Doha Qatar
| | - Robert Tuba
- Institute of Materials and Environmental Chemistry; Research Centre for Natural Sciences; Hungarian Academy of Sciences; Magyar tudósok körútja 2., P.O. Box 286 1519 Budapest Hungary
- Department of Chemistry; Texas A&M University at Qatar; P.O. Box 23874 Doha Qatar
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17
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Ivry E, Ben-Asuly A, Goldberg I, Lemcoff NG. Amino acids as chiral anionic ligands for ruthenium based asymmetric olefin metathesis. Chem Commun (Camb) 2015; 51:3870-3. [PMID: 25656548 DOI: 10.1039/c5cc00052a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Several amino acid ligands were introduced into the Hoveyda-Grubbs 2nd generation complex by a facile anionic ligand exchange. The chiral pre-catalysts obtained displayed enantioselectivity in asymmetric ring-closing and ring-opening cross-metathesis reactions. Reduction of the lability of the carboxylate ligands was found to be cardinal for improving the observed enantiomeric product enrichment.
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Affiliation(s)
- Elisa Ivry
- Chemistry Department, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
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18
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Lummiss JAM, Higman CS, Fyson DL, McDonald R, Fogg DE. The divergent effects of strong NHC donation in catalysis. Chem Sci 2015; 6:6739-6746. [PMID: 29861923 PMCID: PMC5947514 DOI: 10.1039/c5sc02592c] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/05/2015] [Indexed: 11/30/2022] Open
Abstract
The inverse relationship between NHC donicity and catalyst initiation.
Strong σ-donation from NHC ligands (NHC = N-heterocyclic carbene) is shown to have profoundly conflicting consequences for the reactivity of transition-metal catalysts. Such donation is regarded as central to high catalyst activity in many contexts, of which the second-generation Grubbs metathesis catalysts (RuCl2(NHC)(PCy3)(
Created by potrace 1.16, written by Peter Selinger 2001-2019
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CHPh), GII) offer an early, prominent example. Less widely recognized is the dramatically inhibiting impact of NHC ligation on initiation of GII, and on re-entry into the catalytic cycle from the resting-state methylidene species RuCl2(NHC)(PCy3)(
Created by potrace 1.16, written by Peter Selinger 2001-2019
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CH2), GIIm. Both GII and the methylidene complexes are activated by dissociation of PCy3. The impact of NHC donicity on the rate of PCy3 loss is explored in a comparison of s-GIIm, vs.u-GIIm, in which the NHC ligand is saturated H2IMes or unsaturated IMes, respectively. PCy3 loss is nearly an order of magnitude slower for the IMes derivative (a difference that is replicated, albeit smaller, for the benzylidene precatalysts GII). Proposed as an overlooked contributor to these rate differences is an increase in the Ru–PCy3 bond strength arising from π-back-donation onto the phosphine ligand. Strong σ-donation from the IMes ligand, coupled with the inability of this unsaturated NHC to participate in significant π-backbonding, amplifies Ru → PCy3 π-back-donation. The resulting increase in Ru–P bond strength greatly inhibits entry into the active cycle. For s-GII, in contrast, the greater π-acceptor capacity of the NHC ligand enables competing Ru → H2IMes back-donation (as confirmed by NOE experiments, which reveal restricted rotation about the Ru–NHC bond for H2IMes, but not IMes). Ru → PCy3 back-donation is thus attenuated in the H2IMes complexes, accounting for the greater lability of the PCy3 ligand in s-GIIm and s-GII. Similarly inhibited initiation is predicted for other metal–NHC catalysts in which a π-acceptor ligand L must be dissociated to permit substrate binding. Conversely, enhanced reactivity can be expected where such L ligands are pure σ-donors. These effects are expected to be particularly dramatic where the NHC ligand has minimal π-acceptor capacity (as in the unsaturated Arduengo carbenes), and in geometries that maximize NHC–M–L orbital interactions.
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Affiliation(s)
- Justin A M Lummiss
- Center for Catalysis Research & Innovation and Department of Chemistry , University of Ottawa , Ottawa , K1N 6N5 , Canada .
| | - Carolyn S Higman
- Center for Catalysis Research & Innovation and Department of Chemistry , University of Ottawa , Ottawa , K1N 6N5 , Canada .
| | - Devon L Fyson
- Center for Catalysis Research & Innovation and Department of Chemistry , University of Ottawa , Ottawa , K1N 6N5 , Canada .
| | - Robert McDonald
- Department of Chemistry , University of Alberta , Edmonton , T6G 2G2 , AB , Canada
| | - Deryn E Fogg
- Center for Catalysis Research & Innovation and Department of Chemistry , University of Ottawa , Ottawa , K1N 6N5 , Canada .
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Guidone S, Nahra F, Slawin AMZ, Cazin CSJ. Ruthenium indenylidene "1(st) generation" olefin metathesis catalysts containing triisopropyl phosphite. Beilstein J Org Chem 2015; 11:1520-7. [PMID: 26425210 PMCID: PMC4578444 DOI: 10.3762/bjoc.11.166] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/05/2015] [Indexed: 11/23/2022] Open
Abstract
The reaction of triisopropyl phosphite with phosphine-based indenylidene pre-catalysts affords “1st generation” cis-complexes. These have been used in olefin metathesis reactions. The cis-Ru species exhibit noticeable differences with the trans-Ru parent complexes in terms of structure, thermal stability and reactivity. Experimental data underline the importance of synergistic effects between phosphites and L-type ligands.
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Affiliation(s)
- Stefano Guidone
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, UK, KY16 9ST, UK
| | - Fady Nahra
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, UK, KY16 9ST, UK
| | - Alexandra M Z Slawin
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, UK, KY16 9ST, UK
| | - Catherine S J Cazin
- EaStCHEM School of Chemistry, University of St Andrews, St Andrews, UK, KY16 9ST, UK
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20
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Poater A, Cavallo L. A comprehensive study of olefin metathesis catalyzed by Ru-based catalysts. Beilstein J Org Chem 2015; 11:1767-80. [PMID: 26664596 PMCID: PMC4660983 DOI: 10.3762/bjoc.11.192] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/04/2015] [Indexed: 01/02/2023] Open
Abstract
During a Ru-catalyzed reaction of an olefin with an alkylidene moiety that leads to a metallacycle intermediate, the cis insertion of the olefin can occur from two different directions, namely side and bottom with respect to the phosphine or N-heterocyclic ligand (NHC), depending on the first or second generation Grubbs catalyst. Here, DFT calculations unravel to which extent the bottom coordination of olefins with respect is favored over the side coordination through screening a wide range of catalysts, including first and second generation Grubbs catalysts as well as the subsequent Hoveyda derivatives. The equilibrium between bottom and side coordination is influenced by sterics, electronics, and polarity of the solvent. The side attack is favored for sterically less demanding NHC and/or alkylidene ligands. Moreover the generation of a 14-electron species is also discussed, with either pyridine or phosphine ligands to dissociate.
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Affiliation(s)
- Albert Poater
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Campus Montilivi, 17071 Girona, Catalonia, Spain
| | - Luigi Cavallo
- KAUST Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
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21
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Borguet Y, Zaragoza G, Demonceau A, Delaude L. Ruthenium catalysts bearing a benzimidazolylidene ligand for the metathetical ring-closure of tetrasubstituted cycloolefins. Dalton Trans 2015; 44:9744-55. [PMID: 25734488 DOI: 10.1039/c5dt00433k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Deprotonation of 1,3-di(2-tolyl)benzimidazolium tetrafluoroborate with a strong base afforded 1,3-di(2-tolyl)benzimidazol-2-ylidene (BTol), which dimerized progressively into the corresponding dibenzotetraazafulvalene. The complexes [RhCl(COD)(BTol)] (COD is 1,5-cyclooctadiene) and cis-[RhCl(CO)2(BTol)] were synthesized to probe the steric and electronic parameters of BTol. Comparison of the percentage of buried volume (%VBur) and of the Tolman electronic parameter (TEP) of BTol with those determined previously for 1,3-dimesitylbenzimidazol-2-ylidene (BMes) revealed that the two N-heterocyclic carbenes displayed similar electron donicities, yet the 2-tolyl substituents took a slightly greater share of the rhodium coordination sphere than the mesityl groups, due to a more pronounced tilt. The anti,anti conformation adopted by BTol in the molecular structure of [RhCl(COD)(BTol)] ensured nonetheless a remarkably unhindered access to the metal center, as evidenced by steric maps. Second-generation ruthenium-benzylidene and isopropoxybenzylidene complexes featuring the BTol ligand were obtained via phosphine exchange from the first generation Grubbs and Hoveyda-Grubbs catalysts, respectively. The atropisomerism of the 2-tolyl substituents within [RuCl2(=CHPh)(PCy3)(BTol)] was investigated by using variable temperature NMR spectroscopy, and the molecular structures of all four possible rotamers of [RuCl2(=CH-o-O(i)PrC6H4)(BTol)] were determined by X-ray crystallography. Both complexes were highly active at promoting the ring-closing metathesis (RCM) of model α,ω-dienes. The replacement of BMes with BTol was particularly beneficial to achieve the ring-closure of tetrasubstituted cycloalkenes. More specifically, the stable isopropoxybenzylidene chelate enabled an almost quantitative RCM of two challenging substrates, viz., diethyl 2,2-bis(2-methylallyl)malonate and N,N-bis(2-methylallyl)tosylamide, within a few hours at 60 °C.
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Affiliation(s)
- Yannick Borguet
- Laboratory of Organometallic Chemistry and Homogeneous Catalysis, Institut de Chimie (B6a), Université de Liège, Sart-Tilman par 4000, Liège, Belgium.
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Nelson DJ, Manzini S, Urbina-Blanco CA, Nolan SP. Key processes in ruthenium-catalysed olefin metathesis. Chem Commun (Camb) 2015; 50:10355-75. [PMID: 24931143 DOI: 10.1039/c4cc02515f] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
While the fundamental series of [2+2]cycloadditions and retro[2+2]cycloadditions that make up the pathways of ruthenium-catalysed metathesis reactions is well-established, the exploration of mechanistic aspects of alkene metathesis continues. In this Feature Article, modern mechanistic studies of the alkene metathesis reaction, catalysed by well-defined ruthenium complexes, are discussed. Broadly, these concern the processes of pre-catalyst initiation, propagation and decomposition, which all have a considerable impact on the overall efficiency of metathesis reactions.
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Affiliation(s)
- David J Nelson
- EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, UK.
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Guidone S, Songis O, Falivene L, Nahra F, Slawin AMZ, Jacobsen H, Cavallo L, Cazin CSJ. Ruthenium Olefin Metathesis Catalysts Containing Fluoride. ACS Catal 2015. [DOI: 10.1021/acscatal.5b00219] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stefano Guidone
- EaStCHEM
School of Chemistry, University of St Andrews, St. Andrews KY16 9ST, United Kingdom
| | - Olivier Songis
- EaStCHEM
School of Chemistry, University of St Andrews, St. Andrews KY16 9ST, United Kingdom
| | - Laura Falivene
- Physical
Sciences and Engineering, Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Fady Nahra
- EaStCHEM
School of Chemistry, University of St Andrews, St. Andrews KY16 9ST, United Kingdom
| | - Alexandra M. Z. Slawin
- EaStCHEM
School of Chemistry, University of St Andrews, St. Andrews KY16 9ST, United Kingdom
| | - Heiko Jacobsen
- KemKom, 1215 Ursulines
Avenue, New
Orleans, Louisiana 70116, United States
| | - Luigi Cavallo
- Physical
Sciences and Engineering, Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Catherine S. J. Cazin
- EaStCHEM
School of Chemistry, University of St Andrews, St. Andrews KY16 9ST, United Kingdom
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Guidone S, Songis O, Nahra F, Cazin CSJ. Conducting Olefin Metathesis Reactions in Air: Breaking the Paradigm. ACS Catal 2015. [DOI: 10.1021/acscatal.5b00197] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stefano Guidone
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, KY16 9ST, United Kingdom
| | - Olivier Songis
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, KY16 9ST, United Kingdom
| | - Fady Nahra
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, KY16 9ST, United Kingdom
| | - Catherine S. J. Cazin
- EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews, KY16 9ST, United Kingdom
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26
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Torker S, Khan RKM, Hoveyda AH. The influence of anionic ligands on stereoisomerism of Ru carbenes and their importance to efficiency and selectivity of catalytic olefin metathesis reactions. J Am Chem Soc 2014; 136:3439-55. [PMID: 24533571 DOI: 10.1021/ja410606b] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Investigations detailed herein provide insight regarding the mechanism of stereochemical inversion of stereogenic-at-Ru carbene complexes through a nonolefin metathesis-based polytopal rearrangement pathway. Computational analyses (DFT) reveal that there are two key factors that generate sufficient energy barriers that are responsible for the possibility of isolation and characterization of high-energy, but kinetically stable, intermediates: (1) donor-donor interactions that involve the anionic ligands and the strongly electron donating carbene groups and (2) dipolar effects arising from the syn relationship between the anionic groups (iodide and phenoxide). We demonstrate that a Brønsted acid lowers barriers to facilitate isomerization, and that the positive influence of a proton source is the result of its ability to diminish the repulsive electronic interactions originating from the anionic ligands. The implications of the present studies regarding a more sophisticated knowledge of the role of anionic units on the efficiency of Ru-catalyzed olefin metathesis reactions are discussed. The electronic basis for the increased facility with which allylic alcohols participate in olefin metathesis processes will be presented as well. Finally, we illustrate how a better understanding of the role of anionic ligands has served as the basis for successful design of Ru-based Z-selective catalysts for alkene metathesis.
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Affiliation(s)
- Sebastian Torker
- Department of Chemistry, Merkert Chemistry Center, Boston College , Chestnut Hill, Massachusetts 02467, United States
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The Influence of Structure on Reactivity in Alkene Metathesis. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2014. [DOI: 10.1016/b978-0-12-800256-8.00002-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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28
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Herndon JW. The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2011. Coord Chem Rev 2013. [DOI: 10.1016/j.ccr.2013.05.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Urbina-Blanco CA, Bantreil X, Wappel J, Schmid TE, Slawin AMZ, Slugovc C, Cazin CSJ. Mixed N-Heterocyclic Carbene/Phosphite Ruthenium Complexes: The Effect of a Bulkier NHC. Organometallics 2013. [DOI: 10.1021/om4004362] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
| | - Xavier Bantreil
- EaStCHEM
School of Chemistry, University of St Andrews, St Andrews KY16 9ST, U.K
| | - Julia Wappel
- Institute
for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Thibault E. Schmid
- EaStCHEM
School of Chemistry, University of St Andrews, St Andrews KY16 9ST, U.K
| | | | - Christian Slugovc
- Institute
for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
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Skowerski K, Kasprzycki P, Bieniek M, Olszewski TK. Efficient, durable and reusable olefin metathesis catalysts with high affinity to silica gel. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.06.056] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Czaban J, Schertzer BM, Grela K. Low Catalyst Loadings in Self-Metathesis of 1-Dodecene. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201200713] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Schmid TE, Jones DC, Songis O, Diebolt O, Furst MRL, Slawin AMZ, Cazin CSJ. Mixed phosphine/N-heterocyclic carbene palladium complexes: synthesis, characterization and catalytic use in aqueous Suzuki–Miyaura reactions. Dalton Trans 2013; 42:7345-53. [DOI: 10.1039/c2dt32858e] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Bantreil X, Poater A, Urbina-Blanco CA, Bidal YD, Falivene L, Randall RAM, Cavallo L, Slawin AMZ, Cazin CSJ. Synthesis and Reactivity of Ruthenium Phosphite Indenylidene Complexes. Organometallics 2012. [DOI: 10.1021/om300703p] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Xavier Bantreil
- EaStCHEM
School of Chemistry, University of St Andrews, St Andrews KY16 9ST, U.K
| | - Albert Poater
- Institut de Quı́mica
Computacional, Departament de Quı́mica, Universitat de Girona, Campus de Montilivi,
E-17071 Girona, Spain
| | | | - Yannick D. Bidal
- EaStCHEM
School of Chemistry, University of St Andrews, St Andrews KY16 9ST, U.K
| | - Laura Falivene
- Dipartimento di Chimica e Biologia, Università di Salerno, Via Ponte don Melillo, I-84084 Fisciano
(SA), Italy
| | | | - Luigi Cavallo
- Dipartimento di Chimica e Biologia, Università di Salerno, Via Ponte don Melillo, I-84084 Fisciano
(SA), Italy
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Guidone S, Blondiaux E, Samojłowicz C, Gułajski Ł, Kędziorek M, Malińska M, Pazio A, Woźniak K, Grela K, Doppiu A, Cazin CSJ. Catalytic and Structural Studies of Hoveyda-Grubbs Type Pre-Catalysts Bearing Modified Ether Ligands. Adv Synth Catal 2012. [DOI: 10.1002/adsc.201200385] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Tuba R, Brothers EN, Reibenspies JH, Bazzi HS, Gladysz JA. Crystal Structure and Computational Investigation of an Analogue of Grubbs’ Second Generation Catalyst with a Fluorous Phosphine. Inorg Chem 2012; 51:9943-9. [DOI: 10.1021/ic301434g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Robert Tuba
- Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar
| | - Edward N. Brothers
- Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar
| | - Joseph H. Reibenspies
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Hassan S. Bazzi
- Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
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Peeck LH, Savka RD, Plenio H. Fast Olefin Metathesis at Low Catalyst Loading. Chemistry 2012; 18:12845-53. [DOI: 10.1002/chem.201201010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 06/22/2012] [Indexed: 11/06/2022]
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Songis O, Slawin AMZ, Cazin CSJ. An unusual cationic Ru(ii) indenylidene complex and its Ru(iii) derivative—efficient catalysts for high temperature olefinmetathesis reactions. Chem Commun (Camb) 2012; 48:1266-8. [DOI: 10.1039/c2cc15903a] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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