1
|
|
2
|
Azpíroz R, Greger I, Oro LA, Passarelli V, Castarlenas R, Pérez‐Torrente JJ. Preparation of Butadienylpyridines by Iridium-NHC-Catalyzed Alkyne Hydroalkenylation and Quinolizine Rearrangement. Chemistry 2021; 27:11868-11878. [PMID: 33998070 PMCID: PMC8453560 DOI: 10.1002/chem.202101414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Indexed: 11/08/2022]
Abstract
Iridium(I) N-heterocyclic carbene complexes of formula Ir(κ2 O,O'-BHetA)(IPr)(η2 -coe) [BHetA=bis-heteroatomic acidato, acetylacetonate or acetate; IPr=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-carbene; coe=cyclooctene] have been prepared by treating Ir(κ2 O,O'-BHetA)(η2 -coe)2 complexes with IPr. These complexes react with 2-vinylpyridine to afford the hydrido-iridium(III)-alkenyl cyclometalated derivatives IrH(κ2 O,O'-BHetA)(κ2 N,C-C7 H6 N)(IPr) through the iridium(I) intermediate Ir(κ2 O,O'-BHetA)(IPr)(η2 -C7 H7 N). The cyclometalated IrH(κ2 O,O'-acac)(κ2 N,C-C7 H6 N)(IPr) complex efficiently catalyzes the hydroalkenylation of aromatic and aliphatic terminal alkynes and enynes with 2-vinylpyridine to afford 2-(4R-butadienyl)pyridines with Z,E configuration as the major reaction products (yield up to 89 %). In addition, unprecedented (Z)-2-butadienyl-5R-pyridine derivatives have been obtained as minor reaction products (yield up to 21 %) from the elusive 1Z,3gem-butadienyl hydroalkenylation products. These compounds undergo a thermal 6π-electrocyclization to afford bicyclic 4H-quinolizine derivatives that, under catalytic reaction conditions, tautomerize to 6H-quinolizine to afford the (Z)-2-(butadienyl)-5R-pyridine by a retro-electrocyclization reaction.
Collapse
Affiliation(s)
- Ramón Azpíroz
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea-ISQCHUniversidad de Zaragoza-CSIC, Facultad de Ciencias50009ZaragozaSpain
| | - Ingo Greger
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea-ISQCHUniversidad de Zaragoza-CSIC, Facultad de Ciencias50009ZaragozaSpain
- CLARIANT, Gendorf Site84508BurgkirchenGermany
| | - Luis A. Oro
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea-ISQCHUniversidad de Zaragoza-CSIC, Facultad de Ciencias50009ZaragozaSpain
| | - Vincenzo Passarelli
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea-ISQCHUniversidad de Zaragoza-CSIC, Facultad de Ciencias50009ZaragozaSpain
| | - Ricardo Castarlenas
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea-ISQCHUniversidad de Zaragoza-CSIC, Facultad de Ciencias50009ZaragozaSpain
| | - Jesús J. Pérez‐Torrente
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea-ISQCHUniversidad de Zaragoza-CSIC, Facultad de Ciencias50009ZaragozaSpain
| |
Collapse
|
3
|
van Vuuren E, Malan FP, Landman M. Multidentate NHC complexes of group IX metals featuring carbon-based tethers: Synthesis and applications. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213731] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
4
|
Lenczyk C, Roy DK, Nitsch J, Radacki K, Rauch F, Dewhurst RD, Bickelhaupt FM, Marder TB, Braunschweig H. Steric Effects Dictate the Formation of Terminal Arylborylene Complexes of Ruthenium from Dihydroboranes. Chemistry 2019; 25:13566-13571. [PMID: 31433081 PMCID: PMC7079023 DOI: 10.1002/chem.201902890] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Indexed: 11/08/2022]
Abstract
The steric and electronic properties of aryl substituents in monoaryl borohydrides (Li[ArBH3 ]) and dihydroboranes were systematically varied and their reactions with [Ru(PCy3 )2 HCl(H2 )] (Cy: cyclohexyl) were studied, resulting in bis(σ)-borane or terminal borylene complexes of ruthenium. These variations allowed for the investigation of the factors involved in the activation of dihydroboranes in the synthesis of terminal borylene complexes. The complexes were studied by multinuclear NMR spectroscopy, mass spectrometry, X-ray diffraction analysis, and density functional theory (DFT) calculations. The experimental and computational results suggest that the ortho-substitution of the aryl groups is necessary for the formation of terminal borylene complexes.
Collapse
Affiliation(s)
- Carsten Lenczyk
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Dipak Kumar Roy
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Discipline of Chemistry, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore, 453552, M.P., India
| | - Jörn Nitsch
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Krzysztof Radacki
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Florian Rauch
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Rian D Dewhurst
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - F Matthias Bickelhaupt
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM), Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, (The Netherlands), and Institute for Molecules and Materials (IMM), Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
| | - Todd B Marder
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg (Germany), and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| |
Collapse
|
5
|
Ramasamy B, P PA, Gangwar MK, Ghosh P. Asymmetric Transfer Hydrogenation ofα,β-Unsaturated Carbonyl Compounds to Saturated Alcohols as Catalyzed by Iridium Complexes of Tricyclic Bioxazoline-Fused Imidazole-Derived N-Heterocyclic Carbene Ligands. ChemistrySelect 2019. [DOI: 10.1002/slct.201803293] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Balasubramaniyam Ramasamy
- BASF Chemicals India Pvt. Ltd; Innovation campus, Navi; Mumbai 400 705
- Department of Chemistry; Indian Institute of Technology Bombay, Powai; Mumbai 400 076
| | - Prakasham. A. P
- Department of Chemistry; Indian Institute of Technology Bombay, Powai; Mumbai 400 076
| | - Manoj Kumar Gangwar
- Department of Chemistry; Indian Institute of Technology Bombay, Powai; Mumbai 400 076
| | - Prasenjit Ghosh
- Department of Chemistry; Indian Institute of Technology Bombay, Powai; Mumbai 400 076
| |
Collapse
|
6
|
|
7
|
Weinstein CM, Junor GP, Tolentino DR, Jazzar R, Melaimi M, Bertrand G. Highly Ambiphilic Room Temperature Stable Six-Membered Cyclic (Alkyl)(amino)carbenes. J Am Chem Soc 2018; 140:9255-9260. [PMID: 29954178 DOI: 10.1021/jacs.8b05518] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cyclic (alkyl)(amino)carbenes with a six-membered backbone were prepared. Compared to their five-membered analogues, they feature increased % Vbur and enhanced donor and acceptor properties, as evidenced by the observed n → π* transition trailing into the visible region. The high ambiphilic character even allows for the intramolecular insertion of the carbene into an unactivated C(sp3)-H bond. When used as ligands, they outcompete the five-membered analogues in the palladium-mediated α-arylation of ketones with aryl chlorides.
Collapse
Affiliation(s)
- Cory M Weinstein
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0358 , United States
| | - Glen P Junor
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0358 , United States
| | - Daniel R Tolentino
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0358 , United States
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0358 , United States
| | - Mohand Melaimi
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0358 , United States
| | - Guy Bertrand
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0358 , United States
| |
Collapse
|
8
|
Babón JC, Esteruelas MA, Fernández I, López AM, Oñate E. Evidence for a Bis(Elongated σ)-Dihydrideborate Coordinated to Osmium. Inorg Chem 2018; 57:4482-4491. [DOI: 10.1021/acs.inorgchem.8b00155] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juan C. Babón
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Miguel A. Esteruelas
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Israel Fernández
- Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Ana M. López
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Enrique Oñate
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| |
Collapse
|
9
|
Adams GM, Colebatch AL, Skornia JT, McKay AI, Johnson HC, Lloyd−Jones GC, Macgregor SA, Beattie NA, Weller AS. Dehydropolymerization of H3B·NMeH2 To Form Polyaminoboranes Using [Rh(Xantphos-alkyl)] Catalysts. J Am Chem Soc 2018; 140:1481-1495. [DOI: 10.1021/jacs.7b11975] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gemma M. Adams
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Annie L. Colebatch
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Joseph T. Skornia
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Alasdair I. McKay
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Heather C. Johnson
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Guy C. Lloyd−Jones
- School
of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Stuart A. Macgregor
- Institute
of Chemical Sciences, Heriot Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Nicholas A. Beattie
- Institute
of Chemical Sciences, Heriot Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Andrew S. Weller
- Chemistry Research Laboratories, Mansfield Road, Oxford OX1 3TA, United Kingdom
| |
Collapse
|
10
|
Bailey GA, Lummiss JAM, Foscato M, Occhipinti G, McDonald R, Jensen VR, Fogg DE. Decomposition of Olefin Metathesis Catalysts by Brønsted Base: Metallacyclobutane Deprotonation as a Primary Deactivating Event. J Am Chem Soc 2017; 139:16446-16449. [DOI: 10.1021/jacs.7b08578] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gwendolyn A. Bailey
- Center
for Catalysis Research and Innovation, and Department of Chemistry
and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
| | - Justin A. M. Lummiss
- Center
for Catalysis Research and Innovation, and Department of Chemistry
and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
| | - Marco Foscato
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Giovanni Occhipinti
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Robert McDonald
- X-Ray
Crystallography Laboratory, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Vidar R. Jensen
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Deryn E. Fogg
- Center
for Catalysis Research and Innovation, and Department of Chemistry
and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5, Canada
| |
Collapse
|
11
|
Agnew DW, Moore CE, Rheingold AL, Figueroa JS. Controlled cis Labilization of CO from Manganese(I) Mixed Carbonyl/Isocyanide Complexes: An Entry Point to Coordinatively Unsaturated Metallo-Lewis Acids. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00792] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Douglas W. Agnew
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093, United States
| | - Curtis E. Moore
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093, United States
| | - Arnold L. Rheingold
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093, United States
| | - Joshua S. Figueroa
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093, United States
| |
Collapse
|
12
|
Wurm T, Mulks F, Böhling CRN, Riedel D, Zargaran P, Rudolph M, Rominger F, Hashmi ASK. Synthesis of Different Classes of Six-Membered Gold(I) NHC Complexes by the Isonitrile Route. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | | | | | | | | | | | | | - A. Stephen K. Hashmi
- Chemistry
Department, King Abdulaziz University (KAU), Jeddah 21589, Saudi Arabia
| |
Collapse
|
13
|
Koppaka A, Yempally V, Zhu L, Fortman GC, Temprado M, Hoff CD, Captain B. Synthesis of [Pt(SnBut3)(IBut)(μ-H)]2, a Coordinatively Unsaturated Dinuclear Compound which Fragments upon Addition of Small Molecules to Form Mononuclear Pt–Sn Complexes. Inorg Chem 2015; 55:307-21. [DOI: 10.1021/acs.inorgchem.5b02441] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anjaneyulu Koppaka
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| | - Veeranna Yempally
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| | - Lei Zhu
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| | - George C. Fortman
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| | - Manuel Temprado
- Department of Analytical Chemistry, Physical
Chemistry and Chemical Engineering, Universidad de Alcalá, Madrid 28801, Spain
| | - Carl D. Hoff
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| | - Burjor Captain
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| |
Collapse
|
14
|
Arnold N, Mozo S, Paul U, Radius U, Braunschweig H. Aryldihydroborane Coordination to Iridium and Osmium Hydrido Complexes. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00788] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicole Arnold
- Institut für
Anorganische
Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Silvia Mozo
- Institut für
Anorganische
Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Ursula Paul
- Institut für
Anorganische
Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Udo Radius
- Institut für
Anorganische
Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Holger Braunschweig
- Institut für
Anorganische
Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| |
Collapse
|
15
|
Affiliation(s)
- Alexey V. Polukeev
- Centre
for Analysis and Synthesis,
Department of Chemistry, Lund University, P.O. Box 124, S-22100 Lund, Sweden
| | - Ola F. Wendt
- Centre
for Analysis and Synthesis,
Department of Chemistry, Lund University, P.O. Box 124, S-22100 Lund, Sweden
| |
Collapse
|
16
|
Riddlestone IM, Abdalla JA, Aldridge S. Coordination and Activation of EH Bonds (E=B, Al, Ga) at Transition Metal Centers. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2015. [DOI: 10.1016/bs.adomc.2015.02.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
17
|
Xu S, Manna K, Ellern A, Sadow AD. Mixed N-Heterocyclic Carbene–Bis(oxazolinyl)borato Rhodium and Iridium Complexes in Photochemical and Thermal Oxidative Addition Reactions. Organometallics 2014. [DOI: 10.1021/om500891h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Songchen Xu
- U.S. Department
of Energy Ames Laboratory and Department of Chemistry, Iowa State University, 1605 Gilman Hall, Ames, Iowa 50011, United States
| | - Kuntal Manna
- U.S. Department
of Energy Ames Laboratory and Department of Chemistry, Iowa State University, 1605 Gilman Hall, Ames, Iowa 50011, United States
| | - Arkady Ellern
- U.S. Department
of Energy Ames Laboratory and Department of Chemistry, Iowa State University, 1605 Gilman Hall, Ames, Iowa 50011, United States
| | - Aaron D. Sadow
- U.S. Department
of Energy Ames Laboratory and Department of Chemistry, Iowa State University, 1605 Gilman Hall, Ames, Iowa 50011, United States
| |
Collapse
|
18
|
Phillips N, Dodson T, Tirfoin R, Bates JI, Aldridge S. Expanded-ring N-heterocyclic carbenes for the stabilization of highly electrophilic gold(I) cations. Chemistry 2014; 20:16721-31. [PMID: 25336057 DOI: 10.1002/chem.201404939] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Indexed: 12/31/2022]
Abstract
Strategies for the synthesis of highly electrophilic Au(I) complexes from either hydride- or chloride-containing precursors have been investigated by employing sterically encumbered Dipp-substituted expanded-ring NHCs (Dipp=2,6-iPr2 C6 H3 ). Thus, complexes of the type (NHC)AuH have been synthesised (for NHC=6-Dipp or 7-Dipp) and shown to feature significantly more electron-rich hydrides than those based on ancillary imidazolylidene donors. This finding is consistent with the stronger σ-donor character of these NHCs, and allows for protonation of the hydride ligand. Such chemistry leads to the loss of dihydrogen and to the trapping of the [(NHC)Au](+) fragment within a dinuclear gold cation containing a bridging hydride. Activation of the hydride ligand in (NHC)AuH by B(C6 F5 )3 , by contrast, generates a species (at low temperatures) featuring a [HB(C6 F5 )3 ](-) fragment with spectroscopic signatures similar to the "free" borate anion. Subsequent rearrangement involves BC bond cleavage and aryl transfer to the carbophilic metal centre. Under halide abstraction conditions utilizing Na[BAr(f) 4 ] (Ar(f) =C6 H3 (CF3 )2 -3,5), systems of the type [(NHC)AuCl] (NHC=6-Dipp or 7-Dipp) generate dinuclear complexes [{(NHC)Au}2 (μ-Cl)](+) that are still electrophilic enough at gold to induce aryl abstraction from the [BAr(f) 4 ](-) counterion.
Collapse
Affiliation(s)
- Nicholas Phillips
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR (UK)
| | | | | | | | | |
Collapse
|
19
|
Ortuño MA, Vidossich P, Conejero S, Lledós A. Orbital-Like Motion of Hydride Ligands around Low-Coordinate Metal Centers. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201407572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
20
|
Ortuño MA, Vidossich P, Conejero S, Lledós A. Orbital-like motion of hydride ligands around low-coordinate metal centers. Angew Chem Int Ed Engl 2014; 53:14158-61. [PMID: 25327539 DOI: 10.1002/anie.201407572] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/30/2014] [Indexed: 11/06/2022]
Abstract
Hydrogen atoms in the coordination sphere of a transition metal are highly mobile ligands. Here, a new type of dynamic process involving hydrides has been characterized by computational means. This dynamic event consists of an orbital-like motion of hydride ligands around low-coordinate metal centers containing N-heterocyclic carbenes. The hydride movement around the carbene-metal-carbene axis is the lowest energy mode connecting energy equivalent isomers. This understanding provides crucial information for the interpretation of NMR spectra.
Collapse
Affiliation(s)
- Manuel A Ortuño
- Departament de Química, Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona, Campus UAB, 08193 Cerdanyola del Vallès (Spain)
| | | | | | | |
Collapse
|