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Vilella-Arribas L, García-Melchor M, Balcells D, Lledós A, López JA, Sancho S, Villarroya BE, del Río MP, Ciriano MA, Tejel C. Rhodium Complexes Promoting C−O Bond Formation in Reactions with Oxygen: The Role of Superoxo Species. Chemistry 2017; 23:5232-5243. [DOI: 10.1002/chem.201605959] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Laia Vilella-Arribas
- Departament de Química; Universitat Autònoma de Barcelona; Cerdanyola del Vallès 08193 Barcelona Spain
| | - Max García-Melchor
- School of Chemistry; Trinity College Dublin; College Green Dublin 2 Ireland
| | - David Balcells
- Centre for Theoretical and Computational Chemistry (CTCC) and Department of Chemistry; University of Oslo; P.O. Box 1033, Blindern 0315 Oslo Norway
| | - Agustí Lledós
- Departament de Química; Universitat Autònoma de Barcelona; Cerdanyola del Vallès 08193 Barcelona Spain
| | - José A. López
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálsis Homogénea (ISQCH); CSIC Universidad de Zaragoza; Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Sofía Sancho
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálsis Homogénea (ISQCH); CSIC Universidad de Zaragoza; Pedro Cerbuna 12 50009 Zaragoza Spain
| | - B. Eva Villarroya
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálsis Homogénea (ISQCH); CSIC Universidad de Zaragoza; Pedro Cerbuna 12 50009 Zaragoza Spain
| | - M. Pilar del Río
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálsis Homogénea (ISQCH); CSIC Universidad de Zaragoza; Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Miguel A. Ciriano
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálsis Homogénea (ISQCH); CSIC Universidad de Zaragoza; Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Cristina Tejel
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálsis Homogénea (ISQCH); CSIC Universidad de Zaragoza; Pedro Cerbuna 12 50009 Zaragoza Spain
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Baumgarth H, Braun T, Braun B, Laubenstein R, Herrmann R. Synthesis of an Iridium Peroxido Complex and Its Reactivity Towards Brønsted Acids. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201500384] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Hanna Baumgarth
- Humboldt‐Universität zu Berlin, Department of Chemistry, Brook‐Taylor‐Straße 2, 12489 Berlin, Germany, http://www2.hu‐berlin.de/chemie/braun
| | - Thomas Braun
- Humboldt‐Universität zu Berlin, Department of Chemistry, Brook‐Taylor‐Straße 2, 12489 Berlin, Germany, http://www2.hu‐berlin.de/chemie/braun
| | - Beatrice Braun
- Humboldt‐Universität zu Berlin, Department of Chemistry, Brook‐Taylor‐Straße 2, 12489 Berlin, Germany, http://www2.hu‐berlin.de/chemie/braun
| | - Reik Laubenstein
- Humboldt‐Universität zu Berlin, Department of Chemistry, Brook‐Taylor‐Straße 2, 12489 Berlin, Germany, http://www2.hu‐berlin.de/chemie/braun
| | - Roy Herrmann
- Humboldt‐Universität zu Berlin, Department of Chemistry, Brook‐Taylor‐Straße 2, 12489 Berlin, Germany, http://www2.hu‐berlin.de/chemie/braun
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Feller M, Ben-Ari E, Diskin-Posner Y, Carmieli R, Weiner L, Milstein D. O2 Activation by Metal–Ligand Cooperation with IrI PNP Pincer Complexes. J Am Chem Soc 2015; 137:4634-7. [DOI: 10.1021/jacs.5b01585] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Moran Feller
- Departments
of †Organic Chemistry and ‡Chemical Research
Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Eyal Ben-Ari
- Departments
of †Organic Chemistry and ‡Chemical Research
Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yael Diskin-Posner
- Departments
of †Organic Chemistry and ‡Chemical Research
Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Raanan Carmieli
- Departments
of †Organic Chemistry and ‡Chemical Research
Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Lev Weiner
- Departments
of †Organic Chemistry and ‡Chemical Research
Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - David Milstein
- Departments
of †Organic Chemistry and ‡Chemical Research
Support, Weizmann Institute of Science, Rehovot 76100, Israel
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Thomsen JM, Huang DL, Crabtree RH, Brudvig GW. Iridium-based complexes for water oxidation. Dalton Trans 2015; 44:12452-72. [DOI: 10.1039/c5dt00863h] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Activation of organometallic Ir precatalysts can yield either homogeneous or heterogeneous water-oxidation catalysts with very high activity.
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Ghosh S, Baik MH. Mechanism of Redox-Active Ligand-Assisted Nitrene-Group Transfer in a ZrIVComplex: Direct Ligand-to-Ligand Charge Transfer Preferred. Chemistry 2014; 21:1780-9. [DOI: 10.1002/chem.201405738] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Indexed: 11/11/2022]
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Walters AJC, Reek JN, de Bruin B. Computed Propagation and Termination Steps in [(Cycloocta-2,6-dien-1-yl)RhIII(polymeryl)]+ Catalyzed Carbene Polymerization Reactions. ACS Catal 2014. [DOI: 10.1021/cs500160c] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Annemarie J. C. Walters
- Van ‘t Hoff Institute
for Molecular Sciences (HIMS), Homogeneous and Supramolecular Catalysis
group, Universiteit van Amsterdam (UvA), P.O. Box 94720, 1090 GS Amsterdam, The Netherlands
| | - Joost N.H. Reek
- Van ‘t Hoff Institute
for Molecular Sciences (HIMS), Homogeneous and Supramolecular Catalysis
group, Universiteit van Amsterdam (UvA), P.O. Box 94720, 1090 GS Amsterdam, The Netherlands
| | - Bas de Bruin
- Van ‘t Hoff Institute
for Molecular Sciences (HIMS), Homogeneous and Supramolecular Catalysis
group, Universiteit van Amsterdam (UvA), P.O. Box 94720, 1090 GS Amsterdam, The Netherlands
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Dauth A, Rigling C, Tsoung J, Love JA. Formation of Substituted Oxa- and Azarhodacyclobutanes. Chemistry 2013; 19:17180-91. [DOI: 10.1002/chem.201302421] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Indexed: 11/06/2022]
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Liu Z, Deeth RJ, Butler JS, Habtemariam A, Newton ME, Sadler PJ. Reduction of Quinones by NADH Catalyzed by Organoiridium Complexes. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201300747] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Liu Z, Deeth RJ, Butler JS, Habtemariam A, Newton ME, Sadler PJ. Reduction of quinones by NADH catalyzed by organoiridium complexes. Angew Chem Int Ed Engl 2013; 52:4194-7. [PMID: 23471835 PMCID: PMC3660790 DOI: 10.1002/anie.201300747] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Zhe Liu
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
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Ghosh S, Baik MH. Redox Properties of Tanaka’s Water Oxidation Catalyst: Redox Noninnocent Ligands Dominate the Electronic Structure and Reactivity. Inorg Chem 2011; 50:5946-57. [DOI: 10.1021/ic102427g] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Soumya Ghosh
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Mu-Hyun Baik
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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Dzik WI, Zhang XP, de Bruin B. Redox noninnocence of carbene ligands: carbene radicals in (catalytic) C-C bond formation. Inorg Chem 2011; 50:9896-903. [PMID: 21520926 DOI: 10.1021/ic200043a] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In this Forum contribution, we highlight the radical-type reactivities of one-electron-reduced Fischer-type carbenes. Carbene complexes of group 6 transition metals (Cr, Mo, and W) can be relatively easily reduced by an external reducing agent, leading to one-electron reduction of the carbene ligand moiety. This leads to the formation of "carbene-radical" ligands, showing typical radical-type reactivities. Fischer-type carbene ligands are thus clearly redox-active and can behave as so-called "redox noninnocent ligands". The "redox noninnocence" of Fischer-type carbene ligands is most clearly illustrated at group 9 transition metals in the oxidation state II+ (Co(II), Rh(II), and Ir(II)). In such carbene complexes, the metal effectively reduces the carbene ligand by one electron in an intramolecular redox process. As a result, the thus formed "carbene radicals" undergo a variety of radical-type C-C and C-H bond formations. The redox noninnocence of Fischer-type carbene ligands is not just a chemical curiosity but, in fact, plays an essential role in catalytic cyclopropanation reactions by cobalt(II) porphyrins. This has led to the successful development of new chiral cobalt(II) porphyrins as highly effective catalysts for asymmetric cyclopropanation with unprecedented reactivity and stereocontrol. The redox noninnocence of the carbene intermediates results in the formation of carbene-radical ligands with nucleophilic character, which explains their effectiveness in the cyclopropanation of electron-deficient olefins and their reduced tendency to mediate carbene dimerization. To the best of our knowledge, this represents the first example in which the redox noninnocence of a reacting ligand plays a key role in a catalytic organometallic reaction. This Forum contribution ends with an outlook on further potential applications of one-electron-activated Fischer-type carbenes in new catalytic reactions.
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Affiliation(s)
- Wojciech I Dzik
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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12
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Dauth A, Love JA. Reactivity by Design—Metallaoxetanes as Centerpieces in Reaction Development. Chem Rev 2011; 111:2010-47. [DOI: 10.1021/cr100388p] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexander Dauth
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
| | - Jennifer A. Love
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
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Meier G, Braun T. A Rhodium Peroxido Complex in Mono-, Di-, and Peroxygenation Reactions. Angew Chem Int Ed Engl 2011; 50:3280-4. [DOI: 10.1002/anie.201007315] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2010] [Indexed: 11/08/2022]
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Meier G, Braun T. A Rhodium Peroxido Complex in Mono-, Di-, and Peroxygenation Reactions. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201007315] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Annen S, Zweifel T, Ricatto F, Grützmacher H. Catalytic Aerobic Dehydrogenative Coupling of Primary Alcohols and Water to Acids Promoted by a Rhodium(I) Amido N-Heterocyclic Carbene Complex. ChemCatChem 2010. [DOI: 10.1002/cctc.201000100] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Popp BV, Morales CM, Landis CR, Stahl SS. Electronic Structural Comparison of the Reactions of Dioxygen and Alkenes with Nitrogen-Chelated Palladium(0). Inorg Chem 2010; 49:8200-7. [DOI: 10.1021/ic100806w] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Brian V. Popp
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706
| | - Christine M. Morales
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706
| | - Clark R. Landis
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706
| | - Shannon S. Stahl
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706
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van der Vlugt J, Reek J. Neutral Tridentate PNP Ligands and Their Hybrid Analogues: Versatile Non-Innocent Scaffolds for Homogeneous Catalysis. Angew Chem Int Ed Engl 2009; 48:8832-46. [DOI: 10.1002/anie.200903193] [Citation(s) in RCA: 380] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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van der Vlugt J, Reek J. Neutrale dreizähnige PNP-Liganden und deren Hybrid-Analoga: vielseitige Liganden für die kooperative homogene Katalyse. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200903193] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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del Río M, Ciriano M, Tejel C. From Olefins to Ketones via a 2-Rhodaoxetane Complex. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200705802] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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del Río M, Ciriano M, Tejel C. From Olefins to Ketones via a 2-Rhodaoxetane Complex. Angew Chem Int Ed Engl 2008; 47:2502-5. [DOI: 10.1002/anie.200705802] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Shul'pin GB, Muratov DV, Shul'pina LS, Kudinov AR, Strelkova TV, Petrovskiy PV. Oxygenation of aromatic hydrocarbons with hydrogen peroxide catalyzed by rhodium carbonyl complexes. Appl Organomet Chem 2008. [DOI: 10.1002/aoc.1459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Reddy PM, Prasad AVSS, Reddy CK, Ravinder V. Synthesis of new macrocyclic rhodium(III) compounds and their utility as catalysts for the oxidation of ascorbic acid. TRANSIT METAL CHEM 2007. [DOI: 10.1007/s11243-007-9037-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Feller M, Ben-Ari E, Gupta T, Shimon LJW, Leitus G, Diskin-Posner Y, Weiner L, Milstein D. Mononuclear Rh(II) PNP-Type Complexes. Structure and Reactivity. Inorg Chem 2007; 46:10479-90. [PMID: 17902648 DOI: 10.1021/ic701044b] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Rh(II) mononuclear complexes [(PNPtBu)RhCl][BF4] (2), [(PNPtBu)Rh(OC(O)CF3)][OC(O)CF3] (4), and [(PNPtBu)Rh(acetone)][BF4]2 (6) were synthesized by oxidation of the corresponding Rh(I) analogs with silver salts. On the other hand, treatment of (PNPtBu)RhCl with AgOC(O)CF3 led only to chloride abstraction, with no oxidation. 2 and 6 were characterized by X-ray diffraction, EPR, cyclic voltammetry, and dipole moment measurements. 2 and 6 react with NO gas to give the diamagnetic complexes [(PNPtBu)Rh(NO)Cl][BF4] (7) and [(PNPtBu)Rh(NO)(acetone)][BF4]2 (8) respectively. 6 is reduced to Rh(I) in the presence of phosphines, CO, or isonitriles to give the Rh(I) complexes [(PNPtBu)Rh(PR3)][BF4] (11, 12) (R = Et, Ph), [(PNPtBu)Rh(CO)][BF4] (13) and [(PNPtBu)Rh(L)][BF4] (15, 16) (L = tert-butyl isonitrile or 2,6-dimethylphenyl isonitrile), respectively. On the other hand, 2 disproportionates to Rh(I) and Rh(III) complexes in the presence of acetonitrile, isonitriles, or CO. 2 is also reduced by triethylphosphine and water to Rh(I) complexes [(PNPtBu)RhCl] (1) and [(PNPtBu)Rh(PEt3)][BF4] (11). When triphenylphosphine and water are used, the reduced Rh(I) complex reacts with a proton, which is formed in the redox reaction, to give a Rh(III) complex with a coordinated BF4, [(PNPtBu)Rh(Cl)(H)(BF4)] (9).
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Affiliation(s)
- Moran Feller
- Department of Organic Chemistry and Unit of Chemical Research Support, The Weizmann Institute of Science, Rehovot 76100, Israel
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Cui W, Li S, Wayland BB. Factors contributing to one-electron metalloradical activation of ethene and carbon monoxide illustrated by reactions of Co(II), Rh(II), and Ir(II) porphyrins. J Organomet Chem 2007. [DOI: 10.1016/j.jorganchem.2007.01.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Hetterscheid DGH, Klop M, Kicken RJNAM, Smits JMM, Reijerse EJ, de Bruin B. Hydrogen-Atom Transfer in Open-Shell Organometallic Chemistry: The Reactivity of RhII(cod) and IrII(cod) Radicals. Chemistry 2007; 13:3386-405. [PMID: 17219454 DOI: 10.1002/chem.200600711] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A series of new metalloradical rhodium and iridium complexes [M(II)(cod)(N-ligand)](2+) in the uncommon oxidation state +II were synthesized by one-electron oxidation of their [M(I)(cod)(N-ligand)](+) precursors (M=Rh, Ir; cod=(Z,Z)-1,5-cyclooctadiene; and N-ligand is a podal bis(pyridyl)amine ligand: N,N-bis(2-pyridylmethyl)amine (dpa), N-(2-pyridylmethyl)-N-(6-methyl-2-pyridylmethyl)amine (pla), or N-benzyl-N,N-bis(6-methyl-2-pyridylmethyl)amine (Bn-dla). EPR spectroscopy, X-ray diffraction, and DFT calculations reveal that each of these [M(II)(cod)(N-ligand)](2+) species adopts a square-pyramidal geometry with the two cod double bonds and the two pyridine fragments in the basal plane and the N(amine) donor at the apical position. The unpaired electron of these species mainly resides at the metal center, but the apical N(amine) donor also carries a considerable fraction of the total spin density (15-18 %). Density functional calculations proved a valuable tool for the analysis and simulation of the experimental EPR spectra. Whereas the M(II)(olefin) complexes are quite stable as solids, in solution they spontaneously transform into a 1:1 mixture of M(III)(allyl) species and protonated M(I)(olefin) complexes (in the forms [M(I)(olefin)(protonated N-ligand)](2+) for M=Rh and [M(III)(H)(olefin)(N-ligand)](2+) for M=Ir). Similar reactions were observed for the related propene complex [M(II)(propene)(Me(2)tpa)](2+) (Me(2)tpa=N,N,N-tris(6-methyl-2-pyridylmethyl)amine). The decomposition rate of the [M(II)(cod)(N-ligand)](2+) species decreases with increasing N-ligand bulk in the following order: dpa>pla>Bn-dla. Decomposition of the most hindered [M(II)(cod)(Bn-dla)](2+) complexes proceeds by a second-order process. The kinetic rate expression v=k(obs)[M(II)](2) in acetone with k(obs)=k'[H(+)][S], where [S] is the concentration of additional coordinating reagents (MeCN), is in agreement with ligand-assisted dissociation of one of the pyridine donors. Solvent coordination results in formation of more open, reactive species. Protonation of the noncoordinating pyridyl group increases the concentration of this species, and thus [H(+)] appears in the kinetic rate expression. The kinetic data are in agreement with bimolecular hydrogen-atom transfer from M(II)(cod) to another M(II) species (DeltaH( not equal)=11.5+/-2 kcal mol(-1), DeltaS( not equal)=-27+/-10 cal K(-1) mol(-1), and DeltaG( not equal)(298 K)=19.5+/-5 kcal mol(-1)).
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de Bruin B, Hetterscheid DGH. Paramagnetic (Alkene)Rh and (Alkene)Ir Complexes: Metal or Ligand Radicals? Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200600923] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Bas de Bruin
- University of Amsterdam, Van't Hoff Institute for Molecular Chemistry (HIMS), Department of Homogeneous and Supramolecular Catalysis, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Fax: +31‐20‐525‐6422
| | - Dennis G. H. Hetterscheid
- Radboud University Nijmegen, Institute for Molecules and Materials (IMM), Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
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