1
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Lassalle S, Petit J, Falconer RL, Hérault V, Jeanneau E, Thieuleux C, Camp C. Reactivity of Tantalum/Iridium and Hafnium/Iridium Alkyl Hydrides with Alkyl Lithium Reagents: Nucleophilic Addition, Alpha-H Abstraction, or Hydride Deprotonation? Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sébastien Lassalle
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128 CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, ESCPE Lyon 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Julien Petit
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128 CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, ESCPE Lyon 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Rosalyn L. Falconer
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128 CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, ESCPE Lyon 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Valentin Hérault
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128 CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, ESCPE Lyon 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Erwann Jeanneau
- Centre de Diffractométrie Henri Longchambon Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, 5 Rue de la Doua, 69100 Villeurbanne, France
| | - Chloé Thieuleux
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128 CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, ESCPE Lyon 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Clément Camp
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128 CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Claude Bernard Lyon 1, ESCPE Lyon 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
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2
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Escomel L, Soulé N, Robin E, Del Rosal I, Maron L, Jeanneau E, Thieuleux C, Camp C. Rational Preparation of Well-Defined Multinuclear Iridium–Aluminum Polyhydride Clusters and Comparative Reactivity. Inorg Chem 2022; 61:5715-5730. [DOI: 10.1021/acs.inorgchem.1c03120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Léon Escomel
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128, CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Lyon 1, ESCPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Naïme Soulé
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128, CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Lyon 1, ESCPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Emmanuel Robin
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128, CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Lyon 1, ESCPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Iker Del Rosal
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, F-31077 Toulouse, France
| | - Laurent Maron
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, F-31077 Toulouse, France
| | - Erwann Jeanneau
- Université de Lyon, Centre de Diffractométrie Henri Longchambon, 5 Rue de la Doua, 69100 Villeurbanne, France
| | - Chloé Thieuleux
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128, CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Lyon 1, ESCPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
| | - Clément Camp
- Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128, CNRS, Université de Lyon, Institut de Chimie de Lyon, Université Lyon 1, ESCPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France
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3
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Affiliation(s)
- Robin N. Perutz
- Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Barbara Procacci
- Department of Chemistry, University of York, York YO10 5DD, United Kingdom
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4
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Ikeda Y, Takano K, Kodama S, Ishii Y. 1,4- and 1,3-Metal Migration in a Cp*IrIII Complex: Experimental Evidence of Direct 1,3-Metal Migration. Organometallics 2014. [DOI: 10.1021/om5005258] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yousuke Ikeda
- Department
of Applied Chemistry,
Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
| | - Koichi Takano
- Department
of Applied Chemistry,
Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
| | - Shintaro Kodama
- Department
of Applied Chemistry,
Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
| | - Youichi Ishii
- Department
of Applied Chemistry,
Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
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5
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Photochemical C–H activation and subsequent aerobic oxidation reactions of benzene with Cp*Ir(CO)2. J Organomet Chem 2013. [DOI: 10.1016/j.jorganchem.2013.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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6
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Kwak J, Ohk Y, Jung Y, Chang S. Rollover cyclometalation pathway in rhodium catalysis: dramatic NHC effects in the C-H bond functionalization. J Am Chem Soc 2012; 134:17778-88. [PMID: 23013604 DOI: 10.1021/ja308205d] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Organometallic chelates are readily obtained upon coordination of metal species to multidentate ligands. Because of the robust structural nature, chelation frequently serves as a driving force in the molecular assembly and chemical architecture, and they are used also as an efficient catalyst in numerous reactions. Described herein is the development of a Rh(NHC) catalytic system for the hydroarylation of alkenes and alkynes with 2,2'-bipyridines (bipy) and 2,2'-biquinolines; the most representative chelating molecules. Initially generated (bipy)Rh(NHC) chelates become labile because of the strong trans-effect of N-heterocyclic carbenes, thus weakening a rhodium-pyridyl bond, which is trans to the bound NHC. Subsequent rollover cyclometalation leads to the C-H bond activation, eventually giving rise to double functionalization of chelate molecules. Density functional calculations are in good agreement with our mechanistic proposal based on the experimental data. The present study elucidated for the first time the dramatic NHC effects on the rollover cyclometalation pathway enabling highly efficient and selective bisfunctionalization of 2,2'-bipyridines and 2,2'-biquinolines.
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Affiliation(s)
- Jaesung Kwak
- Molecular-Level Interface Research Center and Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea
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7
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Gómez-Gallego M, Sierra MA. Kinetic isotope effects in the study of organometallic reaction mechanisms. Chem Rev 2011; 111:4857-963. [PMID: 21545118 DOI: 10.1021/cr100436k] [Citation(s) in RCA: 527] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mar Gómez-Gallego
- Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense, 28040 Madrid, Spain.
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8
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Fooladi E, Krapp A, Sekiguchi O, Tilset M, Uggerud E. Mechanism for C-H bond activation in ethylene in the gas phase vs. in solution - vinylic or agostic? Revisiting the case of protonated Cp*Rh(C(2)H(4))(2). Dalton Trans 2010; 39:6317-26. [PMID: 20523951 DOI: 10.1039/b926542b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
When Cp*Rh(C(2)H(4))(2)H(+) (2) is exposed to C(2)H(4) in the gas phase, inside the cell of an FT-ICR mass spectrometer, the most notable feature is the lack of any bimolecular reactivity. Collisional activation of 2 leads to ethylene loss and formation of Cp*Rh(C(2)H(4)-mu-H)(+) (3). In contrast to the reactivity of 2 in solution, ethylene dimerisation is negligible in the gas phase. Coordinatively unsaturated 3, rather than 2, is the major species in which reactivity is observed to occur. Compound 3 reacts with ethylene in three parallel processes: (a) Slow addition of ethylene to give 2; (b) rapid, intermolecular hydrogen atom exchange (monitored in separate reactions with free C(2)D(4) to give 3-d(1-5)); (c) ligand substitution of ethylene in 3. DFT calculations reproduce these observations, showing low barriers for hydrogen scrambling, high barrier to ligand loss in 2, and even higher barriers to elimination of either H(2) or ethane. Mechanistic models for the elimination and scrambling processes are discussed.
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Affiliation(s)
- Erik Fooladi
- Department of Chemistry and Centre for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315, Oslo, Norway
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Ghosh MK, Tilset M, Venugopal A, Heyn RH, Swang O. Ping-Pong at Gold: Proton Jump Between Coordinated Phenyl and η1-Benzene Ligands, A Computational Study. J Phys Chem A 2010; 114:8135-41. [DOI: 10.1021/jp1040508] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Manik Kumer Ghosh
- Department of Hydrocarbon Process Chemistry, SINTEF Materials and Chemistry, P.O. Box 124 Blindern, N-0314 Oslo, Norway and Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Mats Tilset
- Department of Hydrocarbon Process Chemistry, SINTEF Materials and Chemistry, P.O. Box 124 Blindern, N-0314 Oslo, Norway and Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Ajay Venugopal
- Department of Hydrocarbon Process Chemistry, SINTEF Materials and Chemistry, P.O. Box 124 Blindern, N-0314 Oslo, Norway and Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Richard H. Heyn
- Department of Hydrocarbon Process Chemistry, SINTEF Materials and Chemistry, P.O. Box 124 Blindern, N-0314 Oslo, Norway and Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Ole Swang
- Department of Hydrocarbon Process Chemistry, SINTEF Materials and Chemistry, P.O. Box 124 Blindern, N-0314 Oslo, Norway and Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
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10
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Parmene J, Ivanović-Burmazović I, Tilset M, van Eldik R. Combined Low Temperature Rapid Scan and 1H NMR Mechanistic Study of the Protonation and Subsequent Benzene Elimination from a (Diimine)platinum(II) Diphenyl Complex Relevant to Arene C−H Activation. Inorg Chem 2009; 48:9092-103. [DOI: 10.1021/ic9005746] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jerome Parmene
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Ivana Ivanović-Burmazović
- Inorganic Chemistry, Department of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstrasse 1, D-91058 Erlangen, Germany
| | - Mats Tilset
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Rudi van Eldik
- Inorganic Chemistry, Department of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstrasse 1, D-91058 Erlangen, Germany
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11
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Eguillor B, Esteruelas MA, García-Raboso J, Oliván M, Oñate E. Stoichiometric and Catalytic Deuteration of Pyridine and Methylpyridines by H/D Exchange with Benzene-d6 Promoted by an Unsaturated Osmium Tetrahydride Species. Organometallics 2009. [DOI: 10.1021/om900335b] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Beatriz Eguillor
- Departamento de Química Inorgánica−Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Miguel A. Esteruelas
- Departamento de Química Inorgánica−Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Jorge García-Raboso
- Departamento de Química Inorgánica−Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Montserrat Oliván
- Departamento de Química Inorgánica−Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Enrique Oñate
- Departamento de Química Inorgánica−Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
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12
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Bengali AA, Fan WY, Abdulrazak KT. Trends in the Reactivity of the CpMn(CO)2(η2-arene) Bond [arene = benzene, toluene, o-xylene, m-xylene, p-xylene, and mesitylene]: An Experimental and Theoretical Investigation. Organometallics 2009. [DOI: 10.1021/om801185t] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Ashfaq A. Bengali
- Department of Chemistry, Texas A&M University Qatar, P.O. Box 23874, Doha, Qatar, and Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore 117543
| | - Wai Yip Fan
- Department of Chemistry, Texas A&M University Qatar, P.O. Box 23874, Doha, Qatar, and Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore 117543
| | - Khaldoon T. Abdulrazak
- Department of Chemistry, Texas A&M University Qatar, P.O. Box 23874, Doha, Qatar, and Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore 117543
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13
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Synthesis and characterization of Cp∗MCl(PR3)(S or W-η1-butadienesulfonyl) compounds of rhodium and iridium. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2008.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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Ito JI, Miyakawa T, Nishiyama H. Amine-Assisted C−Cl Bond Activation of Aryl Chlorides by a (Phebox)Rh-Chloro Complex. Organometallics 2008. [DOI: 10.1021/om8002174] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jun-ichi Ito
- Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan
| | - Takeshi Miyakawa
- Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan
| | - Hisao Nishiyama
- Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan
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15
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Herrmann C, Kehr G, Fröhlich R, Erker G. Chemical Behavior of a Pair of (COD)CpRh and −Ir Complexes with Pendant Peripheral −B(C6F5)2 Groups. Organometallics 2008. [DOI: 10.1021/om800195d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christoph Herrmann
- Organisch-Chemisches Institut der Universität Münster, Corrensstrasse 40, 48149 Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut der Universität Münster, Corrensstrasse 40, 48149 Münster, Germany
| | - Roland Fröhlich
- Organisch-Chemisches Institut der Universität Münster, Corrensstrasse 40, 48149 Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut der Universität Münster, Corrensstrasse 40, 48149 Münster, Germany
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16
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Li JL, Geng CY, Huang XR, Zhang X, Sun CC. Theoretical Elucidation of the Platinum-Mediated Arene C−H Activation Reactions. Organometallics 2007. [DOI: 10.1021/om070039d] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ji-Lai Li
- State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People's Republic of China, and State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Cai-Yun Geng
- State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People's Republic of China, and State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Xu-Ri Huang
- State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People's Republic of China, and State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Xiang Zhang
- State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People's Republic of China, and State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Chia-Chung Sun
- State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People's Republic of China, and State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
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Knight LK, Piers WE, McDonald R. β-Diketiminato Scandium Chemistry: Attempted Deprotonation of Cationic Amido Complexes. Organometallics 2006. [DOI: 10.1021/om060197p] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lisa K. Knight
- Departments of Chemistry, University of Calgary, 2500 University Drive, N.W., Calgary, Alberta, Canada T2N 1N4, and University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Warren E. Piers
- Departments of Chemistry, University of Calgary, 2500 University Drive, N.W., Calgary, Alberta, Canada T2N 1N4, and University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Robert McDonald
- Departments of Chemistry, University of Calgary, 2500 University Drive, N.W., Calgary, Alberta, Canada T2N 1N4, and University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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Wik BJ, Lersch M, Krivokapic A, Tilset M. Adding a new dimension to the investigation of platinum-mediated arene C-H activation reactions using 2D NMR exchange spectroscopy. Dynamics of Pt(II) phenyl/benzene site exchange. J Am Chem Soc 2006; 128:2682-96. [PMID: 16492055 DOI: 10.1021/ja056694z] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Protonation of (N-N)PtPh(2) (1; N-N = diimine ArN=CMe-CMe=NAr with Ar = 2,6-Me(2)C(6)H(3) (a), 2,4,6-Me(3)C(6)H(2) (b), 4-Br-2,6-Me(2)C(6)H(2) (c), 3,5-Me(2)C(6)H(3) (d), and 4-CF(3)C(6)H(4) (e)) in the presence of MeCN at ambient temperature generates (N-N)Pt(Ph)(NCMe)(+) (2). At -78 degrees C, protonation of 1a yielded (N-N)PtPh(2)(H)(NCMe)(+) (3a), which produced benzene and 2a at ca. -40 degrees C. Protonation of 1a-e in CD(2)Cl(2)/Et(2)O-d(10) furnished (N-N)Pt(C(6)H(5))(eta(2)-C(6)H(6))(+) (4a-e). The pi-benzene complexes 4a-c, sterically protected at Pt, eliminate benzene at ca. 0 degree C. The sterically less protected 4d-e lose benzene already at -30 degrees C. SST and 2D EXSY NMR demonstrate that phenyl and pi-benzene ligand protons undergo exchange with concomitant symmetrization of the diimine ligand, most likely via oxidative insertion of Pt into a C-H bond of coordinated benzene. The kinetics of the exchange processes for 4a-c were probed by quantitative EXSY spectroscopy, resulting in DeltaH() of 70-72 kJ mol(-1) and DeltaS of 37-48 J K(-1) mol(-1). A large, strongly temperature-dependent H/D kinetic isotope effect (9.7 at -34 degrees C; 6.9 at -19 degrees C) was measured for the dynamic behavior of 4a versus 4a-d(10), consistent with the proposed pi-benzene C-H bond cleavage. The fact that the pi-benzene complex 4a is thermally more robust in the absence of MeCN than is the Pt(IV) hydridodiphenyl complex 3a in the presence of MeCN agrees with the notion that arene elimination from Pt(IV) hydridoaryl complexes occurs via Pt(II) pi-arene intermediates that eliminate the hydrocarbon associatively, in this case, promoted by MeCN. Compounds 1a, 1b, 1d, 2a, and 2b have been crystallographically characterized.
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19
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Fan L, Parkin S, Ozerov OV. Halobenzenes and Ir(I): Kinetic C−H Oxidative Addition and Thermodynamic C−Hal Oxidative Addition. J Am Chem Soc 2005; 127:16772-3. [PMID: 16316208 DOI: 10.1021/ja0557637] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A (PNP)Ir fragment undergoes facile, room-temperature oxidative addition of C-H bonds in arenes and haloarenes in preference to aromatic carbon-halogen bonds. This preference, however, is determined to be kinetic in nature. Oxidative addition of C-Cl and C-Br is preferred thermodynamically. The products of the C-Cl or C-Br oxidative addition are separated from the C-H oxidative addition products by a high activation barrier and are only accessible at >100 degrees C. Of the C-H oxidative addition products of chlorobenzene, the isomer with the o-ClC6H4 ligand has the lowest energy.
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Affiliation(s)
- Lei Fan
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454, USA
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21
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Yung CM, Skaddan MB, Bergman RG. Stoichiometric and Catalytic H/D Incorporation by Cationic Iridium Complexes: A Common Monohydrido-Iridium Intermediate. J Am Chem Soc 2004; 126:13033-43. [PMID: 15469302 DOI: 10.1021/ja046825g] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A mechanistic study of the stoichiometric and catalytic H/D exchange reactions involving cationic iridium complexes is presented. Strong evidence suggests that both stoichiometric and catalytic reactions proceed via a monohydrido-iridium species. Stoichiometric deuterium incorporation reactions introduce multiple deuterium atoms into the organic products when aryliridium compounds CpPMe(3)Ir(C(6)H(4)X)(OTf) (X = H, o-CH(3), m-CH(3), p-CH(3)) react with D(2). Multiple deuteration occurs at the unhindered positions (para and meta) of toluene, when X = CH(3). The multiple-deuteration pathway is suppressed in the presence of an excess of the coordinating ligand, CH(3)CN. The compound CpPMe(3)IrH(OTf) (1-OTf) is observed in low-temperature, stoichiometric experiments to support a monohydrido-iridium intermediate that is responsible for catalyzing multiple deuteration in the stoichiometric system. When paired with acetone-d(6)(), [CpPMe(3)IrH(3)][OTf] (4) catalytically deuterates a wide range of substrates with a variety of functional groups. Catalyst 4 decomposes to [CpPMe(3)Ir(eta(3)-CH(2)C(OH)CH(2))][OTf] (19) in acetone and to [CpPMe(3)IrH(CO)][OTf] (1-CO) in CH(3)OH. The catalytic H/D exchange reaction is not catalyzed by simple H(+) transfer, but instead proceeds by a reversible C-H bond activation mechanism.
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Affiliation(s)
- Cathleen M Yung
- Contribution from Pfizer Global Research and Development, Pfizer Inc., 301 Henrietta Street, Kalamazoo, MI 49007, USA
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Reinhold M, McGrady JE, Perutz RN. A comparison of C-F and C-H bond activation by zerovalent ni and pt: a density functional study. J Am Chem Soc 2004; 126:5268-76. [PMID: 15099111 DOI: 10.1021/ja0396908] [Citation(s) in RCA: 177] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Density functional theory indicates that oxidative addition of the C-F and C-H bonds in C6F6 and C6H6 at zerovalent nickel and platinum fragments, M(H2PCH2CH2PH2), proceeds via initial exothermic formation of an eta2-coordinated arene complex. Two distinct transition states have been located on the potential energy surface between the eta2-coordinated arene and the oxidative addition product. The first, at relatively low energy, features an eta3-coordinated arene and connects two identical eta2-arene minima, while the second leads to cleavage of the C-X bond. The absence of intermediate C-F or C-H sigma complexes observed in other systems is traced to the ability of the 14-electron metal fragment to accommodate the eta3-coordination mode in the first transition state. Oxidative addition of the C-F bond is exothermic at both nickel and platinum, but the barrier is significantly higher for the heavier element as a result of strong 5dpi-ppi repulsions in the transition state. Similar repulsive interactions lead to a relatively long Pt-F bond with a lower stretching frequency in the oxidative addition product. Activation of the C-H bond is, in contrast, exothermic only for the platinum complex. We conclude that the nickel system is better suited to selective C-F bond activation than its platinum analogue for two reasons: the strong thermodynamic preference for C-F over C-H bond activation and the relatively low kinetic barrier.
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Affiliation(s)
- Meike Reinhold
- Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
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23
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Fujita KI, Nakaguma H, Hamada T, Yamaguchi R. Inter- and Intramolecular Activation of Aromatic C−H Bonds by Diphosphine and Hydrido-Bridged Dinuclear Iridium Complexes. J Am Chem Soc 2003; 125:12368-9. [PMID: 14531654 DOI: 10.1021/ja036929b] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reactions of [(Cp*Ir)2(mu-dmpm)(mu-H)2]2+ (1) with NaOtBu in aromatic solvent at room temperature give [(Cp*Ir)(H)(mu-dmpm)(mu-H)(Cp*Ir)(Ar)]+ [Ar = Ph (3), p-Tol (4a), m-Tol (4b), 2-furanyl (5a), 3-furanyl (5b)] via intermolecular aromatic C-H activation. Treatment of [(Cp*Ir)2(mu-dppm)(mu-H)2]2+ (2) with base (Et2NH) results in intramolecular C-H activation of the phenyl group in the dppm ligand to give [(Cp*Ir)(H){mu-PPh(C6H4)CH2PPh2}(mu-H)(Cp*Ir)]+ (6). The structures of 3, 5a, and 6 have been determined by X-ray diffraction methods.
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Affiliation(s)
- Ken-Ichi Fujita
- Graduate School of Human and Environmental Studies, and Graduate School of Global Environmental Studies, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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24
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Rybtchinski B, Cohen R, Ben-David Y, Martin JML, Milstein D. Aromatic vs aliphatic C-H bond activation by rhodium(I) as a function of agostic interactions: catalytic H/D exchange between olefins and methanol or water. J Am Chem Soc 2003; 125:11041-50. [PMID: 12952486 DOI: 10.1021/ja029197g] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aryl-PC type ligand 3, benzyl(di-tert-butyl)phosphane, reacts with [Rh(coe)(2)(solv)(n)()]BF(4) (coe = cyclooctene, solv = solvent), producing the C-H activated complexes 4a-c (solv = (a). acetone, (b). THF, (c). methanol). Complexes 4a-c undergo reversible arene C-H activation (observed by NMR spin saturation transfer experiments, SST) and H/D exchange into the hydride and aryl ortho-H with ROD (R = D, Me). They also promote catalytic H/D exchange into the vinylic C-H bond of olefins, with deuterated methanol or water utilized as D-donors. Unexpectedly, complex 2, based on the benzyl-PC type ligand 1 (analogous to 3), di-tert-butyl(2,4,6-trimethylbenzyl)phosphane, shows a very different reversible C-H activation pattern as observed by SST. It is not active in H/D exchange with ROD and in catalytic H/D exchange with olefins. To clarify our observations regarding C-H activation/reductive elimination in both PC-Rh systems, density functional theory (DFT) calculations were performed. Both nucleophilic (oxidative addition) and electrophilic (H/D exchange) C-H activation proceed through eta(2)-C,H agostic intermediates. In the aryl-PC system the agostic interaction causes C-H bond acidity sufficient for the H/D exchange with water or methanol, which is not the case in the benzyl PC-Rh system. In the latter system the C-H coordination pattern of the methyl controls the reversible C-H oxidative addition leading to energetically different C-H activation processes, in accordance with the experimental observations.
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Affiliation(s)
- Boris Rybtchinski
- Department of Organic Chemistry, The Weizmann Institute of Science, 76100 Rehovot, Israel
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25
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Churchill DG, Janak KE, Wittenberg JS, Parkin G. Normal and inverse primary kinetic deuterium isotope effects for C-H bond reductive elimination and oxidative addition reactions of molybdenocene and tungstenocene complexes: evidence for benzene sigma-complex intermediates. J Am Chem Soc 2003; 125:1403-20. [PMID: 12553844 DOI: 10.1021/ja027670k] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The overall reductive elimination of RH from the ansa-molybdenocene and -tungstenocene complexes [Me(2)Si(C(5)Me(4))(2)]Mo(Ph)H and [Me(2)Si(C(5)Me(4))(2)]W(R)H (R = Me, Ph) is characterized by an inverse primary kinetic isotope effect (KIE) for the tungsten system but a normal KIE for the molybdenum system. Oxidative addition of PhH to [[Me(2)Si(C(5)Me(4))(2)]M] also differs for the two systems, with the molybdenum system exhibiting a substantial intermolecular KIE, while no effect is observed for the tungsten system. These differences in KIEs indicate a significant difference in the reactivity of the hydrocarbon adducts [Me(2)Si(C(5)Me(4))(2)]M(RH) for the molybdenum and tungsten systems. Specifically, oxidative cleavage of [Me(2)Si(C(5)Me(4))(2)]M(RH) is favored over RH dissociation for the tungsten system, whereas RH dissociation is favored for the molybdenum system. A kinetics analysis of the interconversion of [Me(2)Si(C(5)Me(4))(2)]W(CH(3))D and [Me(2)Si(C(5)Me(4))(2)]W(CH(2)D)H, accompanied by elimination of methane, provides evidence that the reductive coupling step in this system is characterized by a normal KIE. This observation demonstrates that the inverse KIE for overall reductive elimination is a result of an inverse equilibrium isotope effect (EIE) and is not a result of an inverse KIE for a single step. A previous report of an inverse kinetic isotope effect of 0.76 for C-H reductive coupling in the [Tp]Pt(CH(3))H(2) system is shown to be erroneous. Finally, a computational study provides evidence that the reductive coupling of [Me(2)Si(C(5)Me(4))(2)]W(Ph)H proceeds via the initial formation of a benzene sigma-complex, rather than an eta(2)-pi-benzene complex.
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Affiliation(s)
- David G Churchill
- Department of Chemistry, Columbia University, New York, New York 10027, USA
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26
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Clot E, Oelckers B, Klahn AH, Eisenstein O, Perutz RN. cis–trans Isomerisation of CpRe(CO)2(H)(ArF) (ArF= C6FnH5−n; n = 0–5) is the rate determining step in C–H activation of fluoroarenes: a DFT study. Dalton Trans 2003. [DOI: 10.1039/b305064e] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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DENSITY FUNCTIONAL STUDIES OF IRIDIUM CATALYZED ALKANE DEHYDROGENATION. ADVANCES IN INORGANIC CHEMISTRY 2003. [DOI: 10.1016/s0898-8838(03)54006-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Norris CM, Reinartz S, White PS, Templeton JL. Barriers for Arene C−H Bond Activation in Platinum(II) η2-Arene Intermediates. Organometallics 2002. [DOI: 10.1021/om020526n] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cynthia M. Norris
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290
| | - Stefan Reinartz
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290
| | - Peter S. White
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290
| | - Joseph L. Templeton
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290
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29
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Krogh-Jespersen K, Czerw M, Goldman AS. Computational and experimental studies of the mechanism of (PCP)Ir-catalyzed acceptorless dehydrogenation of alkanes. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1381-1169(02)00199-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Density functional studies of catalytic alkane dehydrogenation by an iridium pincer complex with and without a hydrogen acceptor. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1381-1169(02)00198-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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31
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Krogh-Jespersen K, Czerw M, Summa N, Renkema KB, Achord PD, Goldman AS. On the mechanism of (PCP)Ir-catalyzed acceptorless dehydrogenation of alkanes: a combined computational and experimental study. J Am Chem Soc 2002; 124:11404-16. [PMID: 12236755 DOI: 10.1021/ja012460d] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pincer complexes of the type ((R)PCP)IrH(2), where ((R)PCP)Ir is [eta(3)-2,6-(R(2)PCH(2))(2)C(6)H(3)]Ir, are the most effective catalysts reported to date for the "acceptorless" dehydrogenation of alkanes to yield alkenes and free H(2). We calculate (DFT/B3LYP) that associative (A) reactions of ((Me)PCP)IrH(2) with model linear (propane, n-PrH) and cyclic (cyclohexane, CyH) alkanes may proceed via classical Ir(V) and nonclassical Ir(III)(eta(2)-H(2)) intermediates. A dissociative (D) pathway proceeds via initial loss of H(2), followed by C-H addition to ((Me)PCP)Ir. Although a slightly higher energy barrier (DeltaE(+ +)) is computed for the D pathway, the calculated free-energy barrier (DeltaG(+ +)) for the D pathway is significantly lower than that of the A pathway. Under standard thermodynamic conditions (STP), C-H addition via the D pathway has DeltaG(o)(+ +) = 36.3 kcal/mol for CyH (35.1 kcal/mol for n-PrH). However, acceptorless dehydrogenation of alkanes is thermodynamically impossible at STP. At conditions under which acceptorless dehydrogenation is thermodynamically possible (for example, T = 150 degrees C and P(H)2 = 1.0 x 10(-7) atm), DeltaG(+ +) for C-H addition to ((Me)PCP)Ir (plus a molecule of free H(2)) is very low (17.5 kcal/mol for CyH, 16.7 kcal/mol for n-PrH). Under these conditions, the rate-determining step for the D pathway is the loss of H(2) from ((Me)PCP)IrH(2) with DeltaG(D)(+ +) approximately DeltaH(D)(+ +) = 27.2 kcal/mol. For CyH, the calculated DeltaG(o)(+ +) for C-H addition to ((Me)PCP)IrH(2) on the A pathway is 35.2 kcal/mol (32.7 kcal/mol for n-PrH). At catalytic conditions, the calculated free energies of C-H addition are 31.3 and 33.7 kcal/mol for CyH and n-PrH addition, respectively. Elimination of H(2) from the resulting "seven-coordinate" Ir-species must proceed with an activation enthalpy at least as large as the enthalpy change of the elimination step itself (DeltaH approximately 11-13 kcal/mol), and with a small entropy of activation. The free energy of activation for H(2) elimination (DeltaG(A)(+ +)) is hence found to be greater than ca. 36 kcal/mol for both CyH and n-PrH under catalytic conditions. The overall free-energy barrier of the A pathway is calculated to be higher than that of the D pathway by ca. 9 kcal/mol. Reversible C-H(D) addition to ((R)PCP)IrH(2) is predicted to lead to H/D exchange, because the barriers for hydride scrambling are extremely low in the "seven-coordinate" polyhydrides. In agreement with calculation, H/D exchange is observed experimentally for several deuteriohydrocarbons with the following order of rates: C(6)D(6) > mesitylene-d(12) > n-decane-d(22) >> cyclohexane-d(12). Because H/D exchange in cyclohexane-d(12) solution is not observed even after 1 week at 180 degrees C, we estimate that the experimental barrier to cyclohexane C-D addition is greater than 36.4 kcal/mol. This value is considerably greater than the experimental barrier for the full catalytic dehydrogenation cycle for cycloalkanes (ca. 31 kcal/mol). Thus, the experimental evidence, in agreement with calculation, strongly indicates that the A pathway is not kinetically viable as a segment of the "acceptorless" dehydrogenation cycle.
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Affiliation(s)
- Karsten Krogh-Jespersen
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08903, USA.
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32
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Adams CS, Legzdins P, Tran E. C−H Activation of Substituted Arenes by Tungsten Alkylidene Complexes: Products, Selectivity, and Mechanism. Organometallics 2002. [DOI: 10.1021/om011000q] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Craig S. Adams
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Peter Legzdins
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Elizabeth Tran
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
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33
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34
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Reinartz S, White PS, Brookhart M, Templeton JL. Structural characterization of an intermediate in arene C-H bond activation and measurement of the barrier to C-H oxidative addition: a platinum(II) eta(2)-benzene adduct. J Am Chem Soc 2001; 123:12724-5. [PMID: 11741456 DOI: 10.1021/ja011765p] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S Reinartz
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, USA
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35
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Hughes RP, Kovacik I, Lindner DC, Smith JM, Willemsen S, Zhang D, Guzei IA, Rheingold AL. Unusual Reactivity of “Proton Sponge” as a Hydride Donor to Transition Metals: Synthesis and Structural Characterization of Fluoroalkyl(hydrido) Complexes of Iridium(III) and Rhodium(III). Organometallics 2001. [DOI: 10.1021/om0102347] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Ivan Kovacik
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Danielle C. Lindner
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Jeremy M. Smith
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Stefan Willemsen
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Donghui Zhang
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Ilia A. Guzei
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
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