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Transition Metal-(μ-Cl)-Aluminum Bonding in α-Olefin and Diene Chemistry. Molecules 2022; 27:molecules27217164. [PMID: 36363991 PMCID: PMC9654437 DOI: 10.3390/molecules27217164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/19/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022] Open
Abstract
Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M−(μ-Cl)−Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M−(μ-Cl)−Al bonding in Ziegler−Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M−(μ-Cl)−Al species into catalytic cycles. In the present review, we have compiled data on the formation of M−(μ-Cl)−Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler−Natta processes and beyond.
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2
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George GM, Wolczanski PT, Cundari TR, MacMillan SN. Reactivity of 1.1.1-Propellane with (silox) 3M (M = Ti, V, Cr): Structures of (silox) 3V═( cC 4H 4)═CH 2 and [(silox) 3Cr–(1.1.1-C 5H 6)−] 2. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gregory M. George
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University Ithaca, New York 14853, United States
| | - Peter T. Wolczanski
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University Ithaca, New York 14853, United States
| | - Thomas R. Cundari
- Department of Chemistry, CasCam University of North Texas Denton, Texas 76201, United States
| | - Samantha N. MacMillan
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University Ithaca, New York 14853, United States
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3
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Suslick BA, Grubbs RB, Waymouth RM, Moore JS. The legacy of Robert H. Grubbs: Scientific brilliance with humble empathy. Chem 2022. [DOI: 10.1016/j.chempr.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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4
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George GM, Wolczanski PT, MacMillan SN. Attempts at Generating Metathesis-Active Fe(IV) and Co(IV) Complexes via the Reactions of (silox)2M(THF)2, [(silox)3M][Na(THF)2] (M = Fe, Co), and Related Species with Propellanes and Triphenylboron. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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5
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Law JA, Bartfield NM, Frederich JH. Site-Specific Alkene Hydromethylation via Protonolysis of Titanacyclobutanes. Angew Chem Int Ed Engl 2021; 60:14360-14364. [PMID: 33871123 DOI: 10.1002/anie.202103278] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Indexed: 11/09/2022]
Abstract
Methyl groups are ubiquitous in biologically active molecules. Thus, new tactics to introduce this alkyl fragment into polyfunctional structures are of significant interest. With this goal in mind, a direct method for the Markovnikov hydromethylation of alkenes is reported. This method exploits the degenerate metathesis reaction between the titanium methylidene unveiled from Cp2 Ti(μ-Cl)(μ-CH2 )AlMe2 (Tebbe's reagent) and unactivated alkenes. Protonolysis of the resulting titanacyclobutanes in situ effects hydromethylation in a chemo-, regio-, and site-selective manner. The broad utility of this method is demonstrated across a series of mono- and di-substituted alkenes containing pendant alcohols, ethers, amides, carbamates, and basic amines.
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Affiliation(s)
- James A Law
- Department of Chemistry and Biochemistry, Florida State University, 95 Cheiftan Way, Tallahassee, FL, 32306, USA
| | - Noah M Bartfield
- Department of Chemistry and Biochemistry, Florida State University, 95 Cheiftan Way, Tallahassee, FL, 32306, USA
| | - James H Frederich
- Department of Chemistry and Biochemistry, Florida State University, 95 Cheiftan Way, Tallahassee, FL, 32306, USA
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6
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Law JA, Bartfield NM, Frederich JH. Site‐Specific Alkene Hydromethylation via Protonolysis of Titanacyclobutanes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- James A. Law
- Department of Chemistry and Biochemistry Florida State University 95 Cheiftan Way Tallahassee FL 32306 USA
| | - Noah M. Bartfield
- Department of Chemistry and Biochemistry Florida State University 95 Cheiftan Way Tallahassee FL 32306 USA
| | - James H. Frederich
- Department of Chemistry and Biochemistry Florida State University 95 Cheiftan Way Tallahassee FL 32306 USA
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7
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Belov DS, Tejeda G, Bukhryakov KV. Olefin Metathesis by First-Row Transition Metals. Chempluschem 2021; 86:924-937. [PMID: 34160903 DOI: 10.1002/cplu.202100192] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/07/2021] [Indexed: 11/06/2022]
Abstract
Catalytic olefin metathesis based on the second- and third-row transition metals has become one of the most powerful transformations in modern organic chemistry. The shift to first-row metals to produce fine and commodity chemicals would be an important achievement to complement existing methods with inexpensive and greener alternatives. In addition, those systems can offer unusual reactivity based on the unique electronic structure of the base metals. In this Minireview, we summarize the progress of the development of alkylidenes and metallacycles of first-row transition metals from scandium to nickel capable of performing cycloaddition and cycloreversion steps, crucial reactions in olefin metathesis. In addition, we will discuss systems capable of performing olefin metathesis; however, the nature of active species is not yet known.
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Affiliation(s)
- Dmitry S Belov
- Chemistry and Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL, 33199, USA
| | - Gabriela Tejeda
- Chemistry and Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL, 33199, USA
| | - Konstantin V Bukhryakov
- Chemistry and Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL, 33199, USA
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8
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Kurogi T, Kuroki K, Moritani S, Takai K. Structural elucidation of a methylenation reagent of esters: synthesis and reactivity of a dinuclear titanium(iii) methylene complex. Chem Sci 2021; 12:3509-3515. [PMID: 34163624 PMCID: PMC8179466 DOI: 10.1039/d0sc06366e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Transmetallation of a zinc methylene complex [ZnI(tmeda)]2(μ-CH2) with a titanium(iii) chloride [TiCl3(tmeda)(thf)] produced a titanium methylene complex. The X-ray diffraction study displayed a dinuclear methylene structure [TiCl(tmeda)]2(μ-CH2)(μ-Cl)2. Treatment of an ester with the titanium methylene complex resulted in methylenation of the ester carbonyl to form a vinyl ether. The titanium methylene complex also reacted with a terminal olefin, resulting in olefin-metathesis and olefin-homologation. Cyclopropanation by methylene transfer from the titanium methylene proceeded by use of a 1,3-diene. The mechanistic study of the cyclopropanation reaction by the density functional theory calculations was also reported. Transmetallation of a zinc methylene complex [ZnI(tmeda)]2(μ-CH2) with a titanium(iii) chloride [TiCl3(tmeda)(thf)] produced a titanium methylene complex.![]()
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Affiliation(s)
- Takashi Kurogi
- Division of Applied Chemistry, Graduate School of National Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
| | - Kaito Kuroki
- Division of Applied Chemistry, Graduate School of National Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
| | - Shunsuke Moritani
- Division of Applied Chemistry, Graduate School of National Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
| | - Kazuhiko Takai
- Division of Applied Chemistry, Graduate School of National Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
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9
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Birkelbach VM, Kracht F, Dietrich HM, Stuhl C, Maichle-Mössmer C, Anwander R. A Rare-Earth-Metal Ensemble of the Tebbe Reagent: Scope of Coligands and Carbonyl Olefination. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00447] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Verena M. Birkelbach
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Felix Kracht
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - H. Martin Dietrich
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Christoph Stuhl
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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10
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George GM, Wolczanski PT, MacMillan SN, Cundari TR. Unrealized concepts of masked alkylidenes in (PNP)FeXY systems and alternative approaches to LnXmFe(IV)=CHR. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114460] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Bazarova ZB, Soroka LS, Lyapkov AA, Yusubov МS, Verpoort F. Synthesis of polydicyclopentadiene using the Cp 2TiCl 2/Et 2AlCl catalytic system and thin-layer oxidation of the polymer in air. Beilstein J Org Chem 2019; 15:733-745. [PMID: 30992721 PMCID: PMC6444398 DOI: 10.3762/bjoc.15.69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 03/04/2019] [Indexed: 11/30/2022] Open
Abstract
The polymerization process of dicyclopentadiene using a multicomponent catalytic system based on bis(cyclopentadienyl)titanium dichloride and diethylaluminum chloride was studied. It was demonstrated that the application of an excess of the aluminum component leads to the formation of stable charged complexes of blue discoloration, which initiate cationic polymerization of dicyclopentadiene. Unstabilized thin layers of obtained polydicyclopentadiene undergo oxidation and structuring under atmospheric oxygen. Oxidation of polydicyclopentadiene films in air occurs slowly during several weeks and can be determined by the increase of carbonyl and hydroxyl adsorption bands in infrared spectra. Along with oxidation, cross-linking processes occur in polymers, which lead to a change in physical parameters of the layers, and more precisely to a decrease in the permeability of atmospheric oxygen through the layers. Consequently, this leads to the transition of the oxidation from a kinetic mode into a diffusive mode. Such structural changes do not occur in a polymer that was stabilized by adding an antioxidant.
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Affiliation(s)
- Zhargolma B Bazarova
- National Research Tomsk Polytechnic University, Tomsk, 634050, Russian Federation
| | - Ludmila S Soroka
- National Research Tomsk Polytechnic University, Tomsk, 634050, Russian Federation
| | - Alex A Lyapkov
- National Research Tomsk Polytechnic University, Tomsk, 634050, Russian Federation
| | - Мekhman S Yusubov
- National Research Tomsk Polytechnic University, Tomsk, 634050, Russian Federation
| | - Francis Verpoort
- National Research Tomsk Polytechnic University, Tomsk, 634050, Russian Federation.,Laboratory of Organometallics, Catalysis and Ordered Materials, State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, China.,College of Arts and Sciences, Khalifa University of Science and Technology, PO Box 127788, Abu Dhabi, UAE.,Ghent University, Global Campus Songdo, 119 Songdomunhwa-Ro, Yeonsu-Gu, Incheon 406-840, South Korea
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12
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Gordon C, Yamamoto K, Liao WC, Allouche F, Andersen RA, Copéret C, Raynaud C, Eisenstein O. Metathesis Activity Encoded in the Metallacyclobutane Carbon-13 NMR Chemical Shift Tensors. ACS CENTRAL SCIENCE 2017; 3:759-768. [PMID: 28776018 PMCID: PMC5532720 DOI: 10.1021/acscentsci.7b00174] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Indexed: 06/02/2023]
Abstract
Metallacyclobutanes are an important class of organometallic intermediates, due to their role in olefin metathesis. They can have either planar or puckered rings associated with characteristic chemical and physical properties. Metathesis active metallacyclobutanes have short M-Cα/α' and M···Cβ distances, long Cα/α'-Cβ bond length, and isotropic 13C chemical shifts for both early d0 and late d4 transition metal compounds for the α- and β-carbons appearing at ca. 100 and 0 ppm, respectively. Metallacyclobutanes that do not show metathesis activity have 13C chemical shifts of the α- and β-carbons at typically 40 and 30 ppm, respectively, for d0 systems, with upfield shifts to ca. -30 ppm for the α-carbon of metallacycles with higher d n electron counts (n = 2 and 6). Measurements of the chemical shift tensor by solid-state NMR combined with an orbital (natural chemical shift, NCS) analysis of its principal components (δ11 ≥ δ22 ≥ δ33) with two-component calculations show that the specific chemical shift of metathesis active metallacyclobutanes originates from a low-lying empty orbital lying in the plane of the metallacyclobutane with local π*(M-Cα/α') character. Thus, in the metathesis active metallacyclobutanes, the α-carbons retain some residual alkylidene character, while their β-carbon is shielded, especially in the direction perpendicular to the ring. Overall, the chemical shift tensors directly provide information on the predictive value about the ability of metallacyclobutanes to be olefin metathesis intermediates.
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Affiliation(s)
- Christopher
P. Gordon
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Keishi Yamamoto
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Wei-Chih Liao
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Florian Allouche
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Richard A. Andersen
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Christophe Copéret
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Christophe Raynaud
- Institut
Charles
Gerhardt, UMR 5253 CNRS-Université de Montpellier, Université de Montpellier, 34095 Montpellier, France
| | - Odile Eisenstein
- Institut
Charles
Gerhardt, UMR 5253 CNRS-Université de Montpellier, Université de Montpellier, 34095 Montpellier, France
- Centre
for Theoretical and Computational Chemistry (CTCC), Department of
Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
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14
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Roscales S, Plumet J. Ring Rearrangement Metathesis in 7-Oxabicyclo[2.2.1]heptene (7-Oxanorbornene) Derivatives. Some Applications in Natural Product Chemistry. Nat Prod Commun 2017. [DOI: 10.1177/1934578x1701200517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Metathesis reactions is firmly established as a valuable synthetic tool in organic chemistry, clearly comparable with the venerable Diels-Alder and Wittig reactions and, more recently, with the metal-catalyzed cross-coupling reactions. Metathesis reactions can be considered as a fascinating synthetic methodology, allowing different variants regarding substrate (alkene and alkyne metathesis) and type of metathetical reactions. On the other hand, tandem metathesis reactions such Ring Rearrangement Metathesis (RRM) and the coupling of metathesis reaction with other reactions of alkenes such as Diels-Alder or Heck reactions, makes metathesis one of the most powerful and reliable synthetic procedure.In particular, Ring-Rearrangement Metathesis (RRM) refers to the combination of several metathesis transformations into a domino process such as ring-opening metathesis (ROM)/ring-closing metathesis (RCM) and ROM-cross metathesis (CM) in a one-pot operation. RRM delivers complex frameworks that are difficult to assemble by conventional methods constitutingan atom economic process. RRM is applicable to mono- and polycyclic systems of varying ring sizes such as cyclopropene, cyclobutene, cyclopentene, cyclohexene, pyran systems, bicyclo[2.2.1]heptene derivatives, bicyclo[2.2.2]octene derivatives, bicyclo[3.2.1]octene derivatives and bicyclo[3.2.1]octene derivatives.In this review our attention has focused on the RRM reactions in 7-oxabicyclo[2.2.1]heptene derivatives and on their application in the synthesis of natural products or significant subunits of them.
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Affiliation(s)
- Silvia Roscales
- Technological Institute Pet, 10 Manuel Bartolomé Cossio St, 28040 Madrid, Spain
| | - Joaquín Plumet
- Complutense University, Faculty of Chemistry, Organic Chemistry Department, Ciudad Universitaria, 28040, Madrid, Spain
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Synthesis and Reaction Chemistry of Alkylidene Complexes With Titanium, Zirconium, Vanadium, and Niobium: Effective Catalysts for Olefin Metathesis Polymerization and Other Organic Transformations. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2017. [DOI: 10.1016/bs.adomc.2017.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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16
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Grant LN, Ahn S, Manor BC, Baik MH, Mindiola DJ. Structural elucidation of a mononuclear titanium methylidene. Chem Commun (Camb) 2017; 53:3415-3417. [DOI: 10.1039/c7cc00654c] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The first example of a structurally characterized titanium methylidene, (PN)2TiCH2, has been prepared via one-electron oxidation of (PN)2Ti(CH3) followed by deprotonation with an ylide or by H-atom abstraction using an aryloxyl radical.
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Affiliation(s)
- Lauren N. Grant
- Department of Chemistry
- University of Pennsylvania
- Philadelphia PA
- USA
| | - Seihwan Ahn
- Department of Chemistry
- Korea Advanced Institute of Science and Technology
- Daejeon
- South Korea
- Institute for Basic Science
| | - Brian C. Manor
- Department of Chemistry
- University of Pennsylvania
- Philadelphia PA
- USA
| | - Mu-Hyun Baik
- Department of Chemistry
- Korea Advanced Institute of Science and Technology
- Daejeon
- South Korea
- Institute for Basic Science
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Singh J, Ghosh S, Deb M, Elias AJ. Reactions of Cp2TiMe2 with ferrocene and (ɳ5-Cp)Co(ɳ4-C4Ph4) derived esters and amides: A new route for 1-methylvinyl and methyl ketone derived metal sandwich compounds. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.05.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Tuba R, Xi Z, Bazzi HS, Gladysz JA. Phase‐Transfer Activation of Transition Metal Catalysts. Chemistry 2015; 21:15894-906. [DOI: 10.1002/chem.201502403] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Robert Tuba
- Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha (Qatar)
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, PO Box 286, 1519 Budapest (Hungary)
| | - Zhenxing Xi
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, Texas 77842‐3012 (USA)
| | - 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, PO Box 30012, College Station, Texas 77842‐3012 (USA)
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19
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Synthesis and carbonylation of oxotitanocyclobutanes derived from allene cycloaddition to a monomeric titanocene oxide. Polyhedron 2014. [DOI: 10.1016/j.poly.2014.06.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Sattler A, VanderVelde DG, Labinger JA, Bercaw JE. Lewis Acid Promoted Titanium Alkylidene Formation: Off-Cycle Intermediates Relevant to Olefin Trimerization Catalysis. J Am Chem Soc 2014; 136:10790-800. [PMID: 25007394 DOI: 10.1021/ja5055687] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Aaron Sattler
- Arnold and Mabel Beckman
Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, United States
| | - David G. VanderVelde
- Arnold and Mabel Beckman
Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, United States
| | - Jay A. Labinger
- Arnold and Mabel Beckman
Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, United States
| | - John E. Bercaw
- Arnold and Mabel Beckman
Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, United States
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21
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Pappas I, Chirik PJ. Alkyne Cycloaddition to a Titanocene Oxide as a Route to Cyclopentadienyl Modification. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Pappas I, Chirik PJ. Alkyne Cycloaddition to a Titanocene Oxide as a Route to Cyclopentadienyl Modification. Angew Chem Int Ed Engl 2014; 53:6241-4. [DOI: 10.1002/anie.201403584] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Indexed: 11/07/2022]
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23
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Sauty NF, da Silva LC, Schulz MD, Few CS, Wagener KB. Acyclic diene metathesis polymerization and precision polymers. APPLIED PETROCHEMICAL RESEARCH 2014. [DOI: 10.1007/s13203-014-0045-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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24
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Zhou Y, Chen C, Yan X, Xi C. Chemoselective Phosphination of Titanacyclobutene: A Convenient Method for Synthesis of Allylphosphine Derivatives. Organometallics 2014. [DOI: 10.1021/om500084j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yiqing Zhou
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China
| | - Chao Chen
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China
| | - Xiaoyu Yan
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China
| | - Chanjuan Xi
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China
- State Key Laboratory
of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
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Searles K, Keijzer K, Chen CH, Baik MH, Mindiola DJ. Binary role of an ylide in formation of a terminal methylidene complex of niobium. Chem Commun (Camb) 2014; 50:6267-9. [DOI: 10.1039/c4cc01404a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The methylidene complex can be prepared readily in high yield from the reaction of [(Ar′O)2Nb(CH3)2Cl] (Ar′ = (2,6-CHPh2)2-4-tBu-C6H2) and two equivalents of H2CPPh3. The nucleophilic methylidene of [(Ar′O)2NbCH2(CH3)(H2CPPh3)] can undergo Wittig-like or protonation chemistry to form structurally similar molecules.
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Affiliation(s)
- Keith Searles
- Department of Chemistry
- University of Pennsylvania
- Philadelphia, USA
| | - Karlijn Keijzer
- Department of Chemistry and Molecular Structure Center
- Indiana University
- Bloomington, USA
| | - Chun-Hsing Chen
- Department of Chemistry and Molecular Structure Center
- Indiana University
- Bloomington, USA
| | - Mu-Hyun Baik
- Department of Chemistry and Molecular Structure Center
- Indiana University
- Bloomington, USA
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Thompson R, Nakamaru-Ogiso E, Chen CH, Pink M, Mindiola DJ. Structural Elucidation of the Illustrious Tebbe Reagent. Organometallics 2013. [DOI: 10.1021/om401108b] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rick Thompson
- Department of Chemistry and the Molecular Structure
Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Eiko Nakamaru-Ogiso
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, 295 John Morgan Building, 3620 Hamilton
Walk, Philadelphia, Pennsylvania 19104, United States
| | - Chun-Hsing Chen
- Department of Chemistry and the Molecular Structure
Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Maren Pink
- Department of Chemistry and the Molecular Structure
Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Daniel J. Mindiola
- Department of Chemistry and the Molecular Structure
Center, Indiana University, Bloomington, Indiana 47405, United States
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Zhu S, Liang R, Jiang H, Wu W. An Efficient Route to Polysubstituted Tetrahydronaphthols: Silver-Catalyzed [4+2] Cyclization of 2-Alkylbenzaldehydes and Alkenes. Angew Chem Int Ed Engl 2012; 51:10861-5. [DOI: 10.1002/anie.201204798] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 08/07/2012] [Indexed: 11/08/2022]
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Zhu S, Liang R, Jiang H, Wu W. An Efficient Route to Polysubstituted Tetrahydronaphthols: Silver-Catalyzed [4+2] Cyclization of 2-Alkylbenzaldehydes and Alkenes. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204798] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Eyrisch KK, Müller BK, Herzig C, Nuyken O. Ethenolysis of functionalized cycloolefins. Des Monomers Polym 2012. [DOI: 10.1163/1568555042474194] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Ma G, Ferguson MJ, McDonald R, Cavell RG. Actinide metals with multiple bonds to carbon: synthesis, characterization, and reactivity of U(IV) and Th(IV) bis(iminophosphorano)methandiide pincer carbene complexes. Inorg Chem 2011; 50:6500-8. [PMID: 21667978 DOI: 10.1021/ic102537q] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Treatment of ThCl(4)(DME)(2) or UCl(4) with 1 equiv of dilithiumbis(iminophosphorano) methandiide, [Li(2)C(Ph(2)P═NSiMe(3))(2)] (1), afforded the chloro actinide carbene complexes [Cl(2)M(C(Ph(2)P═NSiMe(3))(2))] (2 (M = Th) and 3 (M = U)) in situ. Stable PCP metal-carbene complexes [Cp(2)Th(C(Ph(2)P═NSiMe(3))(2))] (4), [Cp(2)U(C(Ph(2)P═NSiMe(3))(2))] (5), [TpTh(C(Ph(2)P═NSiMe(3))(2))Cl] (6), and [TpU(C(Ph(2)P═NSiMe(3))(2))Cl] (7) were generated from 2 or 3 by further reaction with 2 equiv of thallium(I) cyclopentadienide (CpTl) in THF to yield 4 or 5 or with 1 equiv of potassium hydrotris(pyrazol-1-yl) borate (TpK) also in THF to give 6 or 7, respectively. The derivative complexes were isolated, and their crystal structures were determined by X-ray diffraction. All of these U (or Th)-carbene complexes (4-7) possess a very short M (Th or U)═carbene bond with evidence for multiple bond character. Gaussian 03 DFT calculations indicate that the M═C double bond is constructed by interaction of the 5f and 6d orbitals of the actinide metal with carbene 2p orbitals of both π and σ character. Complex 3 reacted with acetonitrile or benzonitrile to cyclo-add C≡N to the U═carbon double bond, thereby forming a new C-C bond in a new chelated quadridentate ligand in the bridged dimetallic complexes (9 and 10). A single carbon-U bond is retained. The newly coordinated uranium complex dimerizes with one equivalent of unconverted 3 using two chlorides and the newly formed imine derived from the nitrile as three connecting bridges. In addition, a new crystal structure of [CpUCl(3)(THF)(2)] (8) was determined by X-ray diffraction.
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Affiliation(s)
- Guibin Ma
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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Pinkas J, Gyepes R, Kubišta J, Horáček M, Mach K. Ethene Elimination during Thermolysis of Bis(3-butenyltetramethylcyclopentadienyl)dimethyltitanium. Organometallics 2011. [DOI: 10.1021/om2001487] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jiří Pinkas
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Róbert Gyepes
- J. Selye University, Pedagogical Faculty, Bratislavská cesta 3322, 945 01 Komárno, Slovak Republic
| | - Jiří Kubišta
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Michal Horáček
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Karel Mach
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, 182 23 Prague 8, Czech Republic
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Lozano-Vila AM, Monsaert S, Bajek A, Verpoort F. Ruthenium-Based Olefin Metathesis Catalysts Derived from Alkynes. Chem Rev 2010; 110:4865-909. [PMID: 20392041 DOI: 10.1021/cr900346r] [Citation(s) in RCA: 175] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Ana M. Lozano-Vila
- Department of Inorganic and Physical Chemistry, Laboratory of Organometallic Chemistry and Catalysis, Ghent University, Krijgslaan 281 (S-3), 9000 Ghent, Belgium, Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, Liaoning University, Shenyang 110036, People’s Republic of China, and College of Chemistry, Liaoning University, Shenyang 110036, People’s Republic of China
| | - Stijn Monsaert
- Department of Inorganic and Physical Chemistry, Laboratory of Organometallic Chemistry and Catalysis, Ghent University, Krijgslaan 281 (S-3), 9000 Ghent, Belgium, Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, Liaoning University, Shenyang 110036, People’s Republic of China, and College of Chemistry, Liaoning University, Shenyang 110036, People’s Republic of China
| | - Agata Bajek
- Department of Inorganic and Physical Chemistry, Laboratory of Organometallic Chemistry and Catalysis, Ghent University, Krijgslaan 281 (S-3), 9000 Ghent, Belgium, Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, Liaoning University, Shenyang 110036, People’s Republic of China, and College of Chemistry, Liaoning University, Shenyang 110036, People’s Republic of China
| | - Francis Verpoort
- Department of Inorganic and Physical Chemistry, Laboratory of Organometallic Chemistry and Catalysis, Ghent University, Krijgslaan 281 (S-3), 9000 Ghent, Belgium, Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, Liaoning University, Shenyang 110036, People’s Republic of China, and College of Chemistry, Liaoning University, Shenyang 110036, People’s Republic of China
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Wallace MA, Dean DC, Melillo DG. [14C]Dimethyltitanocene and [14C]Methyl(methyltrimethylsilyl) titanocene-Reagents for the [14C]olefination of carbonyl compounds: synthesis of [14C]Aprepitant. J Labelled Comp Radiopharm 2009. [DOI: 10.1002/jlcr.1667] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Affiliation(s)
- Richard R Schrock
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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Yatsumonji Y, Atake Y, Tsubouchi A, Takeda T. Regio- and stereoselective formation of conjugated dienes by titanocene(ii)-promoted alkylation of propargyl carbonates. Chem Commun (Camb) 2009:3375-7. [PMID: 19503875 DOI: 10.1039/b905782j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conjugated dienes were produced with complete regio- and stereoselectivity by the titanocene(ii)-promoted alkylation of propargyl carbonates via the formation of 2,3,4-trisubstituted titanacyclobutenes.
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Affiliation(s)
- Yasutaka Yatsumonji
- Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
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Abstract
The last one hundred years have witnessed a dramatic increase in the power and reach of total synthesis. The pantheon of accomplishments in the field includes the total synthesis of molecules of unimaginable beauty and diversity such as the four discussed in this article: endiandric acids (1982), calicheamicin gamma(1)(I) (1992), Taxol (1994), and brevetoxin B (1995). Chosen from the collection of the molecules synthesized in the author's laboratories, these structures are but a small fraction of the myriad constructed in laboratories around the world over the last century. Their stories, and the background on which they were based, should serve to trace the evolution of the art of chemical synthesis to its present sharp condition, an emergence that occurred as a result of new theories and mechanistic insights, new reactions, new reagents and catalysts, and new synthetic technologies and strategies. Indeed, the advent of chemical synthesis as a whole must be considered as one of the most influential developments of the twentieth century in terms of its impact on society.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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Scott J, Mindiola DJ. A tribute to Frederick Nye Tebbe. Lewis acid stabilized alkylidyne, alkylidene, and imides of 3d early transition metals. Dalton Trans 2009:8463-72. [DOI: 10.1039/b908684f] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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40
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Friesen DM, Piers WE, Parvez M. Selective Catalytic Dimerization of Neohexene by [Cp*Ti(NPtBu3)Me][B(C6F5)4]. Organometallics 2008. [DOI: 10.1021/om800790d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dawn M. Friesen
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Warren E. Piers
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Masood Parvez
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
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41
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Rowley CN, van der Eide EF, Piers WE, Woo TK. DFT Study of the Isomerization and Spectroscopic/Structural Properties of Ruthenacyclobutane Intermediates Relevant to Olefin Metathesis. Organometallics 2008. [DOI: 10.1021/om8008519] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christopher N. Rowley
- Centre for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada, and Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Edwin F. van der Eide
- Centre for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada, and Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Warren E. Piers
- Centre for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada, and Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Tom K. Woo
- Centre for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada, and Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
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42
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Nicolaou K, Frederick M, Aversa R. Die Entdeckung und Synthese von marinen Polyethern. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200801696] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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43
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Nikiforov GB, Roesky HW, Heisen BC, Grosse C, Oswald RB. Formation of a Titanium Complex with a Ti═CHAl2 Structural Unit from LTiMe3 and Trimethylaluminum. Organometallics 2008. [DOI: 10.1021/om800144v] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Grigory B. Nikiforov
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077, Göttingen, Germany
| | - Herbert W. Roesky
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077, Göttingen, Germany
| | - Burkhard C. Heisen
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077, Göttingen, Germany
| | - Christian Grosse
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077, Göttingen, Germany
| | - Rainer B. Oswald
- Institut für Anorganische Chemie, Universität Göttingen, Tammannstrasse 4, D-37077, Göttingen, Germany
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Abstract
The unprecedented structure of the marine natural product brevetoxin B was elucidated by the research group of Nakanishi and Clardy in 1981. The ladderlike molecular architecture of this fused polyether molecule, its potent toxicity, and fascinating voltage-sensitive sodium channel based mechanism of action immediately captured the imagination of synthetic chemists. Synthetic endeavors resulted in numerous new methods and strategies for the construction of cyclic ethers, and culminated in several impressive total syntheses of this molecule and some of its equally challenging siblings. Of the marine polyethers, maitotoxin is not only the most complex and most toxic of the class, but is also the largest nonpolymeric natural product known to date. This Review begins with a brief history of the isolation of these biotoxins and highlights their biological properties and mechanism of action. Chemical syntheses are then described, with particular emphasis on new methods developed and applied to the total syntheses. The Review ends with a discussion of the, as yet unfinished, story of maitotoxin, and projects into the future of this area of research.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Syatkovskii AI, Babitskii BD. The Reactions of Carbene Complexes of Transition Metals with Unsaturated Hydrocarbons. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc1984v053n07abeh003087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Babushkin DE, Brintzinger HH. Modification of Methylaluminoxane-Activatedansa-Zirconocene Catalysts with Triisobutylaluminum—Transformations of Reactive Cations Studied by NMR Spectroscopy. Chemistry 2007; 13:5294-9. [PMID: 17385201 DOI: 10.1002/chem.200601801] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
When triisobutylaluminum (AliBu(3)) is added to solutions containing methylaluminoxane (MAO) and rac-[Me(2)Si(ind)(2)ZrCl(2)] (ind: indenyl) in C(6)D(6), NMR spectra show that methyl-bridged mixed-alkylaluminum dimers Al(mu-Me)(2)Me(4-x)iBu(x) predominate. These dimers react with MAO under partial transfer of isobutyl groups and induce a conversion of the initially prevailing cationic trimethylaluminum adduct rac-[Me(2)Si(ind)(2)Zr(mu-Me)(2)AlMe(2) (+)] to rac-[Me(2)Si(ind)(2)Zr(mu-Me)(2)AlMeiBu(+)] and rac-[Me(2)Si(ind)(2)Zr(mu-Me)(2)AliBu(2) (+)]. These species are unstable and release isobutene under formation of zirconocene hydrides.
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Affiliation(s)
- Dmitrii E Babushkin
- Boreskov Institute of Catalysis, Russian Academy of Science, Prospekt Akad.Lavrent'eva 5, 630090 Novosibirsk, Russia
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Feldman J, Schrock RR. Recent Advances in the Chemistry of “ d0” Alkylidene and Metallacyclobutane Complexes. PROGRESS IN INORGANIC CHEMISTRY 2007. [DOI: 10.1002/9780470166406.ch1] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Shono T, Kurashige R, Mukaiyama R, Tsubouchi A, Takeda T. Titanacyclobutenes or titanium vinyl carbene complexes? Reactivity of organotitanium species generated by the reaction of gamma-chloroallyl sulfides with a titanocene(II) reagent. Chemistry 2007; 13:4074-80. [PMID: 17330313 DOI: 10.1002/chem.200601418] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The reactivity of the organotitanium species generated by the reductive titanation of gamma-chloroallyl sulfides with the titanocene(II) reagent [Cp(2)Ti{P(OEt)(3)}(2)] was studied. The organotitanium species formed from alpha-monosubstituted gamma-chloroallyl sulfides reacted with 1,5-diphenylpentan-3-one and styrene to produce conjugated dienes and vinyl cyclopropanes as major products, thus suggesting the formation of vinyl carbene complexes as intermediates. On the contrary, the organotitanium species generated from acyclic beta,gamma-disubstituted gamma-chloroallyl sulfides revealed titanacyclobutene-like reactivity, and their reaction with 1,5-diphenylpentan-3-one produced homoallyl alcohols. These organotitanium species did not react with styrene, but did react with dichlorophenylphosphine to afford phosphacyclobutenes. In the case of beta-monosubstituted, gamma-monosubstituted, and alpha,gamma-disubstituted gamma-chloroallyl sulfides, the organotitanium species reacted with both 1,5-diphenylpentan-3-one and styrene. The former reaction produced homoallyl alcohols and the latter gave vinyl cyclopropanes or unconjugated dienes. These results suggest that titanacyclobutenes and/or titanium vinyl carbene complexes are produced by the reductive titanation of gamma-chloroallyl sulfides depending on their substitution patterns.
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Affiliation(s)
- Tomohiro Shono
- Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
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Grubbs R. Olefin-Metathesis Catalysts for the Preparation of Molecules and Materials (Nobel Lecture 2005). Adv Synth Catal 2007. [DOI: 10.1002/adsc.200600523] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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