1
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Ariai J, Ziegler M, Würtele C, Gellrich U. An N-Heterocyclic Quinodimethane: A Strong Organic Lewis Base Exhibiting Diradical Reactivity. Angew Chem Int Ed Engl 2024; 63:e202316720. [PMID: 38088219 DOI: 10.1002/anie.202316720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 12/11/2023] [Indexed: 01/19/2024]
Abstract
We report the preparation of a new organic σ-donor with a C6H4-linker between an N-heterocyclic carbene (NHC) and an exocyclic methylidene group, which we term N-heterocyclic quinodimethane (NHQ). The aromatization of the C6H4-linker provides a decisive driving force for the reaction of the NHQ with an electrophile and renders the NHQ significantly more basic than analogous NHCs or N-heterocyclic olefins (NHOs), as shown by DFT computations and competition experiments. In solution, the NHQ undergoes an unprecedented dehydrogenative head-to-head dimerization by C-C coupling of the methylidene groups. DFT computations indicate that this reaction proceeds via an open-shell singlet pathway revealing the diradical character of the NHQ. The product of this dimerization can be described as conjugated N-heterocyclic bis-quinodimethane, which according to cyclic voltammetry is a strong organic reducing agent (E1/2=-1.71 V vs. Fc/Fc+) and exhibits a remarkable small singlet-triplet gap of ΔES→T=4.4 kcal mol-1.
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Affiliation(s)
- Jama Ariai
- Institut für Organische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392, Gießen, Germany
| | - Maya Ziegler
- Institut für Organische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392, Gießen, Germany
| | - Christian Würtele
- Institut für Anorganische und Analytische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392, Gießen, Germany
| | - Urs Gellrich
- Institut für Organische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392, Gießen, Germany
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2
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LaPierre EA, Patrick BO, Manners I. Synthesis of Carbene-Stabilized PNPN Fragments and Their Carbene-Dependent Redox Properties. J Am Chem Soc 2024; 146:6326-6335. [PMID: 38408316 DOI: 10.1021/jacs.4c00148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Herein, we report the synthesis of carbene-stabilized 1,3-diaza-2,4-diphosphabutenes CAACMePNPNCAACMe 4CAAC (CAACMe = 1-[2,6-bis(isopropyl)phenyl]-3,3,5,5-tetramethyl-2-pyrrolidinylidene) and IPrPNPNIPr 4NHC (IPr = 1,3-Bis(2,6-diisopropylphenyl)-imidazol-2-ylidene). The bonding in both systems is defined by a delocalized polar covalent π-system, with 4NHC exhibiting increased conjugation relative to 4CAAC. The nature of the stabilizing carbene also influences the redox properties of the compound, with 4CAAC undergoing potassium-mediated reduction to the closed-shell P-P bonded dimer K252, which upon treatment with Kryptofix-2,2,2 converts to the transient radical anion [Kcrypt][5], the formal one-electron reduction product of 4CAAC. In contrast, 4NHC undergoes reversible one-electron oxidation to the stable radical cation [6NHC][SbF6]. Computational and spectroscopic analyses of both radical species are suggestive of unevenly delocalized spin, with the bulk of the spin density residing on phosphorus in both cases.
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Affiliation(s)
- Etienne A LaPierre
- Department of Chemistry, University of Victoria, 3800 Finnerty Rd, Victoria, British Columbia V8P 5C2, Canada
| | - Brian O Patrick
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Ian Manners
- Department of Chemistry, University of Victoria, 3800 Finnerty Rd, Victoria, British Columbia V8P 5C2, Canada
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3
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Berg I, Schio L, Reitz J, Molteni E, Lahav L, Bolaños CG, Goldoni A, Grazioli C, Fratesi G, Hansmann MM, Floreano L, Gross E. Self-Assembled Monolayers of N-Heterocyclic Olefins on Au(111). Angew Chem Int Ed Engl 2023; 62:e202311832. [PMID: 37743324 DOI: 10.1002/anie.202311832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/07/2023] [Accepted: 09/22/2023] [Indexed: 09/26/2023]
Abstract
Self-assembled monolayers (SAMs) of N-heterocyclic olefins (NHOs) have been prepared on Au(111) and their thermal stability, adsorption geometry, and molecular order were characterized by X-ray photoelectron spectroscopy, polarized X-ray absorption spectroscopy, scanning tunneling microscopy (STM), and density functional theory (DFT) calculations. The strong σ-bond character of NHO anchoring to Au induced high geometrical flexibility that enabled a flat-lying adsorption geometry via coordination to a gold adatom. The flat-lying adsorption geometry was utilized to further increase the surface interaction of the NHO monolayer by backbone functionalization with methyl groups that induced high thermal stability and a large impact on work-function values, which outperformed that of N-heterocyclic carbenes. STM measurements, supported by DFT modeling, identified that the NHOs were self-assembled in dimers, trimers, and tetramers constructed of two, three, and four complexes of NHO-Au-adatom. This self-assembly pattern was correlated to strong NHO-Au interactions and steric hindrance between adsorbates, demonstrating the crucial influence of the carbon-metal σ-bond on monolayer properties.
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Affiliation(s)
- Iris Berg
- Institute of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem, 91904, Israel
| | - Luca Schio
- CNR-IOM, Laboratorio TASC, Basovizza SS-14, Km 163.5, Trieste, 34012, Italy
| | - Justus Reitz
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Elena Molteni
- Dipartimento di Fisica "Aldo Pontremoli'' Università degli Studi di Milano, Via Celoria 16, 20133, Milano, Italy
| | - Linoy Lahav
- Institute of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem, 91904, Israel
| | | | - Andrea Goldoni
- Elettra-Sincrotrone Trieste S.C.p.A, Basovizza SS-14, Km 163.5, Trieste, 34149, Italy
| | - Cesare Grazioli
- CNR-IOM, Laboratorio TASC, Basovizza SS-14, Km 163.5, Trieste, 34012, Italy
| | - Guido Fratesi
- Dipartimento di Fisica "Aldo Pontremoli'' Università degli Studi di Milano, Via Celoria 16, 20133, Milano, Italy
| | - Max M Hansmann
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Luca Floreano
- CNR-IOM, Laboratorio TASC, Basovizza SS-14, Km 163.5, Trieste, 34012, Italy
| | - Elad Gross
- Institute of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem, 91904, Israel
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4
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Baird SR, Hupf E, Watson IC, Ferguson MJ, Rivard E. An indium(I) tetramer bound by anionic N-heterocyclic olefins: ambiphilic reactivity, transmetallation and a rare indium-imide. Chem Commun (Camb) 2023; 59:2903-2906. [PMID: 36752173 DOI: 10.1039/d2cc07006e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An organometallic tetrahedron-shaped indium(I) tetramer [(MeIPrCH)In]4 (MeIPrCH = [(MeCNDipp)2CCH]-; Dipp = 2,6-iPr2C6H3) supported by anionic N-heterocyclic olefin (aNHO) ligands is reported. The monomeric unit of this species exhibits both Lewis acidic and basic character at indium, while the steric profile of the aNHO ligand enables isolation of a rare monomeric imide, RInNR'.
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Affiliation(s)
- Samuel R Baird
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada.
| | - Emanuel Hupf
- Institut für Anorganische Chemie und Kristallographie, Universität Bremen, Leobener Str. 7, Bremen 28359, Germany
| | - Ian C Watson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada.
| | - Michael J Ferguson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada.
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta, T6G 2G2, Canada.
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5
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Watson I, Zhou Y, Ferguson M, Rivard E. Group 4 Transition Metal Complexes with Anionic N‐Heterocyclic Olefin Ligands. Z Anorg Allg Chem 2022. [DOI: 10.1002/zaac.202200082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
| | | | | | - Eric Rivard
- University of Alberta Deptm. of Chemistry 11227 Saskatchewan Dr. T6G 2G2 Edmonton CANADA
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6
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Fischer M, Roy MMD, Hüller S, Schmidtmann M, Beckhaus R. Reaction of a bis(pentafulvene)titanium complex with an N-heterocyclic olefin: C-H-activation leads to resonance between a titanium vinyl and titanium alkylidene complex. Dalton Trans 2022; 51:10690-10696. [PMID: 35166757 DOI: 10.1039/d2dt00014h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The N-heterocyclic olefin (NHO) ImMe4CH2 (2) (ImMe4CH2 = (MeCNMe)2CCH2) was employed for the synthesis of the titanium complex 3 derived from an NHO ligand precursor. By reacting 2 with the bis(π-η5:σ-η1-pentafulvene)titanium complex 1a, the terminal ylidic methylene unit of 2 is deprotonated by the quaternary exocyclic carbon atom of one pentafulvene ligand of 1a yielding the titanium complex 3 which bears an anionic NHO ligand (ImMe4CH-). 3 was characterized by NMR spectroscopy, single crystal X-ray diffraction and quantum chemical calculations. The latter highlight that 3 is best described as a titanium vinyl complex with significant contribution of the titanium alkylidene resonance structure.
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Affiliation(s)
- Malte Fischer
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK. .,Institut für Chemie, Fakultät für Mathematik und Naturwissenschaften, Carl von Ossietzky Universität Oldenburg, Postfach 2503, D-26111 Oldenburg, Germany.
| | - Matthew M D Roy
- Department of Chemistry, Catalysis Research Center and Institute for Silicon Chemistry, Technische Universität München, Germany
| | - Sascha Hüller
- Institut für Chemie, Fakultät für Mathematik und Naturwissenschaften, Carl von Ossietzky Universität Oldenburg, Postfach 2503, D-26111 Oldenburg, Germany.
| | - Marc Schmidtmann
- Institut für Chemie, Fakultät für Mathematik und Naturwissenschaften, Carl von Ossietzky Universität Oldenburg, Postfach 2503, D-26111 Oldenburg, Germany.
| | - Rüdiger Beckhaus
- Institut für Chemie, Fakultät für Mathematik und Naturwissenschaften, Carl von Ossietzky Universität Oldenburg, Postfach 2503, D-26111 Oldenburg, Germany.
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7
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Watson IC, Ferguson MJ, Rivard E. Zinc-Mediated Transmetalation as a Route to Anionic N-Heterocyclic Olefin Complexes in the p-Block. Inorg Chem 2021; 60:18347-18359. [PMID: 34738790 DOI: 10.1021/acs.inorgchem.1c02961] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Anionic N-heterocyclic olefins (aNHOs) are suited well for the stabilization of low-coordinate inorganic complexes, due to their steric tunability and strong σ- and π-electron donating abilities. In this study, the new two-coordinate zinc complex (MeIPrCH)2Zn (MeIPrCH = [(MeCNDipp)2C═CH]-, Dipp = 2,6-diisopropylphenyl) is shown to participate in a broad range of metathesis reactions with main group element-based halides and hydrides. In the case of the group 14 halides, Cl2E·dioxane (E = Ge and Sn), transmetalation occurs to form dinuclear propellane-shaped cations, [(MeIPrCHE)2(μ-Cl)]+, while the aNHO-capped phosphine ligand MeIPrCH-PPh2 is obtained when (MeIPrCH)2Zn is combined with ClPPh2. Lastly, ZnH2 elimination drives transmetalation between (MeIPrCH)2Zn and hydroboranes and hydroalumanes, leading to Lewis acidic aNHO-supported -boryl and -alane products.
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Affiliation(s)
- Ian C Watson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada, T6G 2G2
| | - Michael J Ferguson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada, T6G 2G2
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada, T6G 2G2
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8
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Roy MMD, Baird SR, Dornsiepen E, Paul LA, Miao L, Ferguson MJ, Zhou Y, Siewert I, Rivard E. A Stable Homoleptic Divinyl Tetrelene Series. Chemistry 2021; 27:8572-8579. [PMID: 33848023 PMCID: PMC8252546 DOI: 10.1002/chem.202100969] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Indexed: 12/16/2022]
Abstract
The synthesis of the new bulky vinyllithium reagent (Me IPr=CH)Li, (Me IPr=[(MeCNDipp)2 C]; Dipp=2,6-iPr2 C6 H3 ) is reported. This vinyllithium precursor was found to act as a general source of the anionic 2σ, 2π-electron donor ligand [Me IPr=CH]- . Furthermore, a high-yielding route to the degradation-resistant SiII precursor Me IPr⋅SiBr2 is presented. The efficacy of (Me IPr=CH)Li in synthesis was demonstrated by the generation of a complete inorganic divinyltetrelene series (Me IPrCH)2 E: (E=Si to Pb). (Me IPrCH)2 Si: represents the first two-coordinate acyclic silylene not bound by heteroatom donors, with dual electrophilic and nucleophilic character at the SiII center noted. Cyclic voltammetry shows this electron-rich silylene to be a potent reducing agent, rivalling the reducing power of the 19-electron complex cobaltocene (Cp2 Co).
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Affiliation(s)
- Matthew M. D. Roy
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
| | - Samuel R. Baird
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
| | - Eike Dornsiepen
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
| | - Lucas A. Paul
- Universität GöttingenInstitut für Anorganische ChemieTammannstr. 437077GöttingenGermany
| | - Linkun Miao
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
| | - Michael J. Ferguson
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
| | - Yuqiao Zhou
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
| | - Inke Siewert
- Universität GöttingenInstitut für Anorganische ChemieTammannstr. 437077GöttingenGermany
| | - Eric Rivard
- Department of ChemistryUniversity of Alberta11227 Saskatchewan Dr.EdmontonAlbertaT6G 2G2Canada
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9
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Affiliation(s)
- Qiuming Liang
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Kasumi Hayashi
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Datong Song
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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10
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Zhang Z, Huang S, Huang L, Xu X, Zhao H, Yan X. Synthesis of Mesoionic N-Heterocyclic Olefins and Catalytic Application for Hydroboration Reactions. J Org Chem 2020; 85:12036-12043. [DOI: 10.1021/acs.joc.0c00257] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Zengyu Zhang
- Department of Chemistry, Renmin University of China, Beijing 100872, China
| | - Shiqing Huang
- Department of Chemistry, Renmin University of China, Beijing 100872, China
| | - Linwei Huang
- Department of Chemistry, Renmin University of China, Beijing 100872, China
| | - Xingyu Xu
- Department of Chemistry, Renmin University of China, Beijing 100872, China
| | - Hongyan Zhao
- Department of Chemistry, Renmin University of China, Beijing 100872, China
| | - Xiaoyu Yan
- Department of Chemistry, Renmin University of China, Beijing 100872, China
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11
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Hansmann MM, Antoni PW, Pesch H. Stable Mesoionic N-Heterocyclic Olefins (mNHOs). Angew Chem Int Ed Engl 2020; 59:5782-5787. [PMID: 31863704 PMCID: PMC7154647 DOI: 10.1002/anie.201914571] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/16/2019] [Indexed: 01/07/2023]
Abstract
We report a new class of stable mesoionic N-heterocyclic olefins, featuring a highly polarized (strongly ylidic) double bond. The ground-state structure cannot be described through an uncharged mesomeric Lewis-structure, thereby structurally distinguishing them from traditional N-heterocyclic olefins (NHOs). mNHOs can easily be obtained through deprotonation of the corresponding methylated N,N'-diaryl-1,2,3-triazolium and N,N'-diaryl-imidazolium salts, respectively. In their reactivity, they represent strong σ-donor ligands as shown by their coordination complexes of rhodium and boron. Their calculated proton affinities, their experimentally derived basicities (competition experiments), as well as donor abilities (Tolman electronic parameter; TEP) exceed the so far reported class of NHOs.
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Affiliation(s)
- Max M. Hansmann
- Fakultät für Chemie und Chemische BiologieTechnische Universität DortmundOtto-Hahn-Str. 644227DortmundGermany
- Georg-August Universität GöttingenInstitut für Organische und Biomolekulare ChemieTammannstr. 237077GöttingenGermany
| | - Patrick W. Antoni
- Georg-August Universität GöttingenInstitut für Organische und Biomolekulare ChemieTammannstr. 237077GöttingenGermany
| | - Henner Pesch
- Georg-August Universität GöttingenInstitut für Organische und Biomolekulare ChemieTammannstr. 237077GöttingenGermany
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12
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Watson IC, Zhou Y, Ferguson MJ, Kränzlein M, Rieger B, Rivard E. Trialkylaluminum N‐Heterocyclic Olefin (NHO) Adducts as Catalysts for the Polymerization of Michael‐Type Monomers. Z Anorg Allg Chem 2020. [DOI: 10.1002/zaac.201900331] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Ian C. Watson
- Department of Chemistry University of Alberta 11227 Saskatchewan Drive T6G 2G2 Edmonton Alberta Canada
| | - Yuqiao Zhou
- Department of Chemistry University of Alberta 11227 Saskatchewan Drive T6G 2G2 Edmonton Alberta Canada
| | - Michael J. Ferguson
- Department of Chemistry University of Alberta 11227 Saskatchewan Drive T6G 2G2 Edmonton Alberta Canada
| | - Moritz Kränzlein
- Catalysis Research Center & WACKER‐Chair of Macromolecular Chemistry Technical University of Munich Lichtenbergstrasse 4 85748 Garching Germany
| | - Bernhard Rieger
- Catalysis Research Center & WACKER‐Chair of Macromolecular Chemistry Technical University of Munich Lichtenbergstrasse 4 85748 Garching Germany
| | - Eric Rivard
- Department of Chemistry University of Alberta 11227 Saskatchewan Drive T6G 2G2 Edmonton Alberta Canada
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13
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Hupf E, Kaiser F, Lummis PA, Roy MMD, McDonald R, Ferguson MJ, Kühn FE, Rivard E. Linking Low-Coordinate Ge(II) Centers via Bridging Anionic N-Heterocyclic Olefin Ligands. Inorg Chem 2020; 59:1592-1601. [PMID: 31247823 DOI: 10.1021/acs.inorgchem.9b01449] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
We introduce a large-scale synthesis of a sterically encumbered N-heterocyclic olefin (NHO) and illustrate the ability of its deprotonated form to act as an anionic four-electron bridging ligand. The resulting multicenter donating ability has been used to link two low oxidation state Ge(II) centers in close proximity, leading to bridging Ge-Cl-Ge and Ge-H-Ge bonding environments supported by Ge2C2 heterocyclic manifolds. Reduction of a dimeric [RGeCl]2 species (R = anionic NHO, [(MeCNDipp)2C═CH]-; Dipp = 2,6-iPr2C6H3) did not give the expected acyclic RGeGeR analogue of an alkyne, but rather ligand migration/disproportionation transpired to yield the known diorganogermylene R2Ge and Ge metal. This process was examined computationally, and the ability of the reported anionic NHO to undergo atom migration chemistry contrasts with what is typically found with bulky monoanionic ligands (such as terphenyl ligands).
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Affiliation(s)
- Emanuel Hupf
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Felix Kaiser
- Catalysis Research Center and Department of Chemistry , Technische Universität München , Lichtenbergstraβe 4 , 85748 Garching bei München , Germany
| | - Paul A Lummis
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Matthew M D Roy
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Robert McDonald
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Michael J Ferguson
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Fritz E Kühn
- Catalysis Research Center and Department of Chemistry , Technische Universität München , Lichtenbergstraβe 4 , 85748 Garching bei München , Germany
| | - Eric Rivard
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
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14
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Hansmann MM, Antoni PW, Pesch H. Stable Mesoionic N‐Heterocyclic Olefins (mNHOs). Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914571] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Max M. Hansmann
- Fakultät für Chemie und Chemische Biologie Technische Universität Dortmund Otto-Hahn-Str. 6 44227 Dortmund Germany
- Georg-August Universität Göttingen Institut für Organische und Biomolekulare Chemie Tammannstr. 2 37077 Göttingen Germany
| | - Patrick W. Antoni
- Georg-August Universität Göttingen Institut für Organische und Biomolekulare Chemie Tammannstr. 2 37077 Göttingen Germany
| | - Henner Pesch
- Georg-August Universität Göttingen Institut für Organische und Biomolekulare Chemie Tammannstr. 2 37077 Göttingen Germany
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15
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Watson IC, Schumann A, Yu H, Davy EC, McDonald R, Ferguson MJ, Hering‐Junghans C, Rivard E. N‐Heterocyclic Olefin‐Ligated Palladium(II) Complexes as Pre‐Catalysts for Buchwald–Hartwig Aminations. Chemistry 2019; 25:9678-9690. [DOI: 10.1002/chem.201901376] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Ian C. Watson
- Department of ChemistryUniversity of Alberta 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Canada
| | - André Schumann
- Leibniz Institute for CatalysisUniversity of Rostock Albert Einstein Strasse 29a 18059 Rostock Germany
| | - Haoyang Yu
- Department of ChemistryUniversity of Alberta 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Canada
| | - Emma C. Davy
- Department of Physical SciencesQuest University 3200 University Boulevard Squamish British Columbia V8B 0N8 Canada
| | - Robert McDonald
- Department of ChemistryUniversity of Alberta 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Canada
| | - Michael J. Ferguson
- Department of ChemistryUniversity of Alberta 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Canada
| | - Christian Hering‐Junghans
- Leibniz Institute for CatalysisUniversity of Rostock Albert Einstein Strasse 29a 18059 Rostock Germany
| | - Eric Rivard
- Department of ChemistryUniversity of Alberta 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Canada
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16
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Chen X, Li Z, Frenking G, Fernández I, Zhao L, Grützmacher H. Bent Phosphaallenes With "Hidden" Lone Pairs as Ligands. Chemistry 2019; 25:7912-7920. [PMID: 30927503 DOI: 10.1002/chem.201900645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Indexed: 11/11/2022]
Abstract
Phosphaheteroallenes R-P=C=L, with L = N-heterocyclic carbenes (NHCs), can be viewed to a certain extent as phosphaisonitriles stabilized with NHCs, R-P=C:←L. The suitability of these molecules as ligands for coinage-metal ions was investigated and coordination through the central carbon center was observed in most cases. A combination of experiments, spectroscopic methods, and DFT calculations indicates the presence of a hidden electron pair at the carbon center of R-P=C:←L. Remarkably, this lone pair also inserts intramolecularly in C-H bonds showing the carbene-type reactivity which is expected for phosphaisonitriles.
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Affiliation(s)
- Xiaodan Chen
- College of Chemistry and Materials Science, Jinan University, 510632, Guangzhou, P. R. China
| | - Zhongshu Li
- Lehn Institute of Functional Materials (LIFM), School of Chemistry, Sun Yat-Sen University, 510275, Guangzhou, P. R. China.,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, 30071, Tianjin, P. R. China
| | - Gernot Frenking
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35032, Marburg, Germany.,Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for, Advanced Materials, Nanjing Tech University, Nanjing, 211816, P. R. China
| | - Israel Fernández
- Departamento de Química Orgánica I,Centro de Innovación en, Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for, Advanced Materials, Nanjing Tech University, Nanjing, 211816, P. R. China
| | - Hansjörg Grützmacher
- Lehn Institute of Functional Materials (LIFM), School of Chemistry, Sun Yat-Sen University, 510275, Guangzhou, P. R. China.,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, 30071, Tianjin, P. R. China.,Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland
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17
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Rottschäfer D, Sharma MK, Neumann B, Stammler H, Andrada DM, Ghadwal RS. A Modular Access to Divinyldiphosphenes with a Strikingly Small HOMO–LUMO Energy Gap. Chemistry 2019; 25:8127-8134. [DOI: 10.1002/chem.201901204] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Indexed: 12/28/2022]
Affiliation(s)
- Dennis Rottschäfer
- Anorganische Molekülchemie und KatalyseLehrstuhl für Anorganische Chemie und StrukturchemieCentrum für Molekulare MaterialienFakultät für ChemieUniversität Bielefeld Universitätsstr. 25 33615 Bielefeld Germany
| | - Mahendra K. Sharma
- Anorganische Molekülchemie und KatalyseLehrstuhl für Anorganische Chemie und StrukturchemieCentrum für Molekulare MaterialienFakultät für ChemieUniversität Bielefeld Universitätsstr. 25 33615 Bielefeld Germany
| | - Beate Neumann
- Anorganische Molekülchemie und KatalyseLehrstuhl für Anorganische Chemie und StrukturchemieCentrum für Molekulare MaterialienFakultät für ChemieUniversität Bielefeld Universitätsstr. 25 33615 Bielefeld Germany
| | - Hans‐Georg Stammler
- Anorganische Molekülchemie und KatalyseLehrstuhl für Anorganische Chemie und StrukturchemieCentrum für Molekulare MaterialienFakultät für ChemieUniversität Bielefeld Universitätsstr. 25 33615 Bielefeld Germany
| | - Diego M. Andrada
- Allgemeine und Anorganische ChemieUniversität des Saarlandes Campus C4.1 66123 Saarbrücken Germany
| | - Rajendra S. Ghadwal
- Anorganische Molekülchemie und KatalyseLehrstuhl für Anorganische Chemie und StrukturchemieCentrum für Molekulare MaterialienFakultät für ChemieUniversität Bielefeld Universitätsstr. 25 33615 Bielefeld Germany
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18
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Hong M, Chen J, Chen EYX. Polymerization of Polar Monomers Mediated by Main-Group Lewis Acid-Base Pairs. Chem Rev 2018; 118:10551-10616. [PMID: 30350583 DOI: 10.1021/acs.chemrev.8b00352] [Citation(s) in RCA: 170] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The development of new or more sustainable, active, efficient, controlled, and selective polymerization reactions or processes continues to be crucial for the synthesis of important polymers or materials with specific structures or functions. In this context, the newly emerged polymerization technique enabled by main-group Lewis pairs (LPs), termed as Lewis pair polymerization (LPP), exploits the synergy and cooperativity between the Lewis acid (LA) and Lewis base (LB) sites of LPs, which can be employed as frustrated Lewis pairs (FLPs), interacting LPs (ILPs), or classical Lewis adducts (CLAs), to effect cooperative monomer activation as well as chain initiation, propagation, termination, and transfer events. Through balancing the Lewis acidity, Lewis basicity, and steric effects of LPs, LPP has shown several unique advantages or intriguing opportunities compared to other polymerization techniques and demonstrated its broad polar monomer scope, high activity, control or livingness, and complete chemo- or regioselectivity, as well as its unique application in materials chemistry. These advances made in LPP are comprehensively reviewed, with the scope of monomers focusing on heteroatom-containing polar monomers, while the polymerizations mediated by main-group LAs and LBs separately that are most relevant to the LPP are also highlighted or updated. Examples of applying the principles of the LPP and LP chemistry as a new platform for advancing materials chemistry are highlighted, and currently unmet challenges in the field of the LPP, and thus the suggested corresponding future research directions, are also presented.
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Affiliation(s)
- Miao Hong
- State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , Shanghai 200032 , China
| | - Jiawei Chen
- Department of Chemistry , Columbia University , 3000 Broadway , New York , New York 10027 , United States
| | - Eugene Y-X Chen
- Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523 , United States
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19
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Affiliation(s)
- Thomas Xaver Gentner
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Gerd Ballmann
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Jürgen Pahl
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Holger Elsen
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
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20
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Nesterov V, Reiter D, Bag P, Frisch P, Holzner R, Porzelt A, Inoue S. NHCs in Main Group Chemistry. Chem Rev 2018; 118:9678-9842. [PMID: 29969239 DOI: 10.1021/acs.chemrev.8b00079] [Citation(s) in RCA: 518] [Impact Index Per Article: 86.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Since the discovery of the first stable N-heterocyclic carbene (NHC) in the beginning of the 1990s, these divalent carbon species have become a common and available class of compounds, which have found numerous applications in academic and industrial research. Their important role as two-electron donor ligands, especially in transition metal chemistry and catalysis, is difficult to overestimate. In the past decade, there has been tremendous research attention given to the chemistry of low-coordinate main group element compounds. Significant progress has been achieved in stabilization and isolation of such species as Lewis acid/base adducts with highly tunable NHC ligands. This has allowed investigation of numerous novel types of compounds with unique electronic structures and opened new opportunities in the rational design of novel organic catalysts and materials. This Review gives a general overview of this research, basic synthetic approaches, key features of NHC-main group element adducts, and might be useful for the broad research community.
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Affiliation(s)
- Vitaly Nesterov
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Dominik Reiter
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Prasenjit Bag
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Philipp Frisch
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Richard Holzner
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Amelie Porzelt
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
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21
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Roy MM, Miao L, Ferguson MJ, McDonald R, Rivard E. An unexpected Staudinger reaction at an N-heterocyclic carbene-carbon center. CAN J CHEM 2018. [DOI: 10.1139/cjc-2017-0607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The previously unreported carbene-phosphine adduct (IPr)PCl2N3 [IPr = (HCNDipp)2C:; Dipp = 2,6-iPr2C6H3] was synthesized and used as a synthon toward the elusive dichlorophosphazene monomer unit, [Cl2P=N]. (IPr)PCl2N3 was found to undergo halide and azide abstraction when combined with various electrophiles and its thermolysis yielded the unexpected Staudinger reaction product (IPr=N)PCl2.
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Affiliation(s)
- Matthew M.D. Roy
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
| | - Linkun Miao
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
| | - Michael J. Ferguson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
| | - Robert McDonald
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB T6G 2G2, Canada
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22
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Paisley NR, Lui MW, McDonald R, Ferguson MJ, Rivard E. Structurally versatile phosphine and amine donors constructed from N-heterocyclic olefin units. Dalton Trans 2018; 45:9860-70. [PMID: 26924395 DOI: 10.1039/c6dt00299d] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A general strategy for the synthesis of hindered N- and P-based donors is presented whereby the strongly electron releasing N-heterocyclic olefin (NHO) unit, IPr[double bond, length as m-dash]CH-, (IPr[double bond, length as m-dash]CH- = [(HCNDipp)2C[double bond, length as m-dash]CH](-); Dipp = 3,6-(i)Pr2C6H2) is linked to terminally bound phosphine and amine donors. Preliminary coordination chemistry is presented involving phosphine (IPr[double bond, length as m-dash]CH)PR2 (R = (i)Pr and Ph) and amine (IPr[double bond, length as m-dash]CH)NMe2 ligands and the Lewis acids BH3 and AuCl. Interestingly, (IPr[double bond, length as m-dash]CH)NMe2 binds AuCl through an exocyclic olefin unit, while the softer phosphorus centers in (IPr[double bond, length as m-dash]CH)PR2 coordinate to yield Au-P linkages; thus the reported NHO-based ligands exhibit tunable binding modes to metals.
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Affiliation(s)
- Nathan R Paisley
- Department of Chemistry, University of Alberta 11227 Saskatchewan Drive, Edmonton, AB, T6G 2G2 Canada.
| | - Melanie W Lui
- Department of Chemistry, University of Alberta 11227 Saskatchewan Drive, Edmonton, AB, T6G 2G2 Canada.
| | - Robert McDonald
- Department of Chemistry, University of Alberta 11227 Saskatchewan Drive, Edmonton, AB, T6G 2G2 Canada.
| | - Michael J Ferguson
- Department of Chemistry, University of Alberta 11227 Saskatchewan Drive, Edmonton, AB, T6G 2G2 Canada.
| | - Eric Rivard
- Department of Chemistry, University of Alberta 11227 Saskatchewan Drive, Edmonton, AB, T6G 2G2 Canada.
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23
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Roy MMD, Rivard E. Pushing Chemical Boundaries with N-Heterocyclic Olefins (NHOs): From Catalysis to Main Group Element Chemistry. Acc Chem Res 2017; 50:2017-2025. [PMID: 28777537 DOI: 10.1021/acs.accounts.7b00264] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
N-Heterocyclic olefins (NHOs) have gone from the topic of a few scattered (but important) reports in the early 1990s to very recently being a ligand/reagent of choice in the far-reaching research fields of organocatalysis, olefin and heterocycle polymerization, and low oxidation state main group element chemistry. NHOs are formally derived by appending an alkylidene (CR2) unit onto an N-heterocyclic carbene (NHC), and their pronounced ylidic character leads to high nucleophilicity and soft Lewis basic character at the ligating carbon atom. These olefinic donors can also be structurally derived from imidazole, triazole, and thiazole-based heterocyclic carbenes and, as a result, have highly tunable electronic and steric properties. In this Account, we will focus on various synthetic routes to imidazole-2-ylidene derived NHOs (sometimes referred to as deoxy-Breslow intermediates) followed by a discussion of the electron-donor ability of this structurally tunable ligand group. It should be mentioned that NHOs have a close structural analogy with Breslow-type intermediates, N-heterocyclic ketene aminals, and β-azolium ylides; while these latter species play important roles in advancing synthetic organic chemistry, discussion in this Account will be confined mostly to imidazole-2-ylidene derived NHOs. In addition, we will cover selected examples from the literature where NHOs and their anionic counterparts, N-heterocyclic vinylenes, are used to access reactive main group species not attainable using traditional ligands. Added motivation for these studies comes from the emerging number of low coordinate main group element based compounds that display reactivity once reserved for precious metal complexes (such as H-H and C-H bond activation). Moreover, NHOs are versatile precursors to new mixed element (P/C and N/C), and potentially bidentate, ligand constructs of great potential in catalysis, where various metal oxidation states and coordination environments need to be stabilized during a catalytic cycle. The most active area of recent growth for NHOs is their use as nucleophiles to promote efficient organocatalytic transformations, including transesterification, carbonyl reduction, and the conversion of CO2 into value added products. Polyesters have also been generated through the NHO-promoted ring-opening polymerization of lactones, and the highly tunable nature of NHO organocatalysts allows for the rapid screening and enhancement of catalytic performance. Therefore, the growing utility of NHOs in the realm of organic and polymer chemistry can be viewed as evidence of the widespread impact of N-heterocyclic olefins on the chemical community. It is hoped that through this Account others will join this flourishing research domain and that the rapid recent growth of NHO chemistry is sustained for the foreseeable future.
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Affiliation(s)
- Matthew M. D. Roy
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta Canada, T6G 2G2
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, Alberta Canada, T6G 2G2
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24
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Causero A, Elsen H, Pahl J, Harder S. Calcium Hydride Reactivity: Formation of an Anionic N-Heterocyclic Olefin Ligand. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201703037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Andrea Causero
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
| | - Holger Elsen
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
| | - Jürgen Pahl
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
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25
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Causero A, Elsen H, Pahl J, Harder S. Calcium Hydride Reactivity: Formation of an Anionic N-Heterocyclic Olefin Ligand. Angew Chem Int Ed Engl 2017; 56:6906-6910. [DOI: 10.1002/anie.201703037] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Indexed: 01/07/2023]
Affiliation(s)
- Andrea Causero
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
| | - Holger Elsen
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
| | - Jürgen Pahl
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry; Universität Erlangen-Nürnberg; Egerlandstrasse 1 91058 Erlangen Germany
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26
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Hering-Junghans C, Andreiuk P, Ferguson MJ, McDonald R, Rivard E. Der Einsatz von N-heterocyclischen Vinylliganden zur Isolierung stabiler Divinylgermylene und eines Germylium-Kations. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201609100] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Christian Hering-Junghans
- Department of Chemistry; University of Alberta; 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Kanada
| | - Patricia Andreiuk
- Department of Chemistry; University of Alberta; 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Kanada
| | - Michael J. Ferguson
- Department of Chemistry; University of Alberta; 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Kanada
| | - Robert McDonald
- Department of Chemistry; University of Alberta; 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Kanada
| | - Eric Rivard
- Department of Chemistry; University of Alberta; 11227 Saskatchewan Drive Edmonton Alberta T6G 2G2 Kanada
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Hering-Junghans C, Andreiuk P, Ferguson MJ, McDonald R, Rivard E. Using N-Heterocyclic Vinyl Ligands to Access Stable Divinylgermylenes and a Germylium Cation. Angew Chem Int Ed Engl 2016; 56:6272-6275. [PMID: 28510351 DOI: 10.1002/anie.201609100] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Indexed: 11/11/2022]
Abstract
Two efficient methods are presented to install σ- and π-electron-donating N-heterocyclic vinyl groups onto main-group elements (E): halosilane elimination and base-induced E-C bond formation. Placement of two NHC=CH- ligands (NHC=N-heterocyclic carbene) onto a GeII center affords a two-coordinate germylene, a heavy congener of the elusive divinyl carbenes. The π-donating ability of this vinylic ligand scaffold was further demonstrated by the synthesis of a three-coordinate germylium cation R3 Ge+ .
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Affiliation(s)
- Christian Hering-Junghans
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Patricia Andreiuk
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Michael J Ferguson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Robert McDonald
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
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28
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Powers K, Hering-Junghans C, McDonald R, Ferguson MJ, Rivard E. Improved synthesis of N-heterocyclic olefins and evaluation of their donor strengths. Polyhedron 2016. [DOI: 10.1016/j.poly.2015.07.070] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Ochiai T, Franz D, Inoue S. Applications of N-heterocyclic imines in main group chemistry. Chem Soc Rev 2016; 45:6327-6344. [DOI: 10.1039/c6cs00163g] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A survey of the most recent progress in the applications of N-heterocyclic imines in main group compounds is given.
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Affiliation(s)
- Tatsumi Ochiai
- Institut für Chemie
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Daniel Franz
- Department of Chemistry
- Institute of Silicon Chemistry and Catalysis Research Center
- Technische Universität München
- 85748 Garching
- Germany
| | - Shigeyoshi Inoue
- Institut für Chemie
- Technische Universität Berlin
- 10623 Berlin
- Germany
- Department of Chemistry
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30
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Abstract
This Perspective article summarizes recent progress from our laboratory in the isolation of reactive main group species using a general donor-acceptor protocol. A highlight of this program is the use of carbon-based donors in combination with suitable Lewis acidic acceptors to yield stable complexes of parent Group 14 element hydrides (e.g. GeH2 and H2SiGeH2). It is anticipated that this strategy could be extended to include new synthetic targets from throughout the Periodic Table with possible applications in bottom-up materials synthesis and main group element catalysis envisioned.
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Affiliation(s)
- Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr, Edmonton, AB, CanadaT6G 2G2.
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31
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Ghadwal RS, Schürmann CJ, Engelhardt F, Steinmetzger C. Unprecedented Borylene Insertion into a C-N Bond. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402750] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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32
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Jia YB, Wang YB, Ren WM, Xu T, Wang J, Lu XB. Mechanistic Aspects of Initiation and Deactivation in N-Heterocyclic Olefin Mediated Polymerization of Acrylates with Alane as Activator. Macromolecules 2014. [DOI: 10.1021/ma500047d] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Yin-Bao Jia
- State Key Laboratory of Fine
Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Yan-Bo Wang
- State Key Laboratory of Fine
Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Wei-Min Ren
- State Key Laboratory of Fine
Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Tieqi Xu
- State Key Laboratory of Fine
Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Jing Wang
- State Key Laboratory of Fine
Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Xiao-Bing Lu
- State Key Laboratory of Fine
Chemicals, Dalian University of Technology, Dalian 116024, China
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33
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Berger CJ, He G, Merten C, McDonald R, Ferguson MJ, Rivard E. Synthesis and luminescent properties of Lewis base-appended borafluorenes. Inorg Chem 2014; 53:1475-86. [PMID: 24428809 DOI: 10.1021/ic402408t] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A series of Lewis base adducts of 9-bromo-9-borafluorene (BrBFl-LB, LB = IPr, IPrCH2, PPh3, and PCy3), parent borafluorenes (HBFl-IPr and HBFl-IPrCH2), and the bisadduct [(DMAP)2BFl]Br were prepared and structurally characterized (IPr = [(HCNDipp)2C:], IPrCH2 = [(HCNDipp)2C═CH2], Dipp = 2,6-i-Pr2C6H3, and DMAP = N,N-dimethylaminopyridine). The adducts BrBFl-IPr, BrBFl-PPh3, BrBFl-PCy3, [(DMAP)2BFl]Br, BrBFl-IPrCH2, and HBFl-IPrCH2 were found to exhibit bright blue luminescence with low to moderately high quantum efficiencies (19 to 63%). Selective irradiation at different excitation wavelengths revealed the presence of two distinct emission processes in the adducts BrBFl-LB, leading to a ligand-independent, presumably borafluorene-based, blue light emission at 435 nm and another less intense emission band in the ultraviolet region (315-324 nm); [(DMAP)2BFl]Br exhibits an emission profile that tails into the visible region. Time-dependent density functional theory studies are also included for representative borafluorene adducts. With a judicious choice of functional groups at boron, one can envisage the future generation of a whole library of 4-coordinate borafluorene-based luminogens that complement the efficient light-emitting behavior known for the widely studied boron-dipyrromethene analogues.
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Affiliation(s)
- Christopher J Berger
- Department of Chemistry, University of Alberta , 11227 Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2G2
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34
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Sabourin KJ, Malcolm AC, McDonald R, Ferguson MJ, Rivard E. Metal-free dehydrogenation of amine-boranes by an N-heterocyclic carbene. Dalton Trans 2013; 42:4625-32. [PMID: 23358571 DOI: 10.1039/c3dt32988g] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The dehydrogenation of primary and secondary amine-boranes (RNH(2)·BH(3) and R(2)NH·BH(3); R = alkyl groups) was studied using the bulky N-heterocyclic carbene IPr (IPr = [(HCNDipp)C:]; Dipp = 2,6-(i)Pr(2)C(6)H(3)) as a stoichiometric dehydrogenation agent. In the case of primary amine-boranes, carbene-bound adducts IPr·BH(2)-NH(R)-BH(3) were obtained in place of the desired polymers [RNH-BH(2)](n). The secondary amine-borane (i)Pr(2)NH·BH(3) participated in dehydrogenation chemistry with IPr to afford the aminoborane [(i)Pr(2)N=BH(2)] and the dihydroaminal IPrH(2) as products. Attempts to induce H(2) elimination from the arylamine-borane DippNH(2)·BH(3) yielded a reaction mixture containing the known species IPr·BH(2)NHDipp, IPr·BH(2)NH(Dipp)-BH(3), free DippNH(2) and IPrH(2). The new hindered aryl-amine borane adduct Ar*NH(2)·BH(3) [Ar* = 2,6-(Ph(2)CH)(2)-4-MeC(6)H(2)] underwent a reaction with IPr to give IPr·BH(3) and free Ar*NH(2), consistent with the presence of a weaker N-B dative bond in Ar*NH(2)·BH(3) relative to its less hindered amine-borane analogues.
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Affiliation(s)
- Kyle J Sabourin
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton, AB, Canada T6G 2G2
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Preparation of a stable disilane amidinium heterocycle and attempted syntheses of an inorganic N-heterocyclic carbene. J Organomet Chem 2013. [DOI: 10.1016/j.jorganchem.2013.04.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Ghadwal RS, Reichmann SO, Engelhardt F, Andrada DM, Frenking G. Facile access to silyl-functionalized N-heterocyclic olefins with HSiCl3. Chem Commun (Camb) 2013; 49:9440-2. [DOI: 10.1039/c3cc45652h] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Hounjet LJ, Caputo CB, Stephan DW. The Lewis acidity of fluorophosphonium salts: access to mixed valent phosphorus(iii)/(v) species. Dalton Trans 2013; 42:2629-35. [DOI: 10.1039/c2dt32711b] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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West JK, Fondong GL, Noll BC, Stahl L. Heavier carbene analogues and their derivatives as κ-El, κ2-El,N, and κ2-N,N′ ligands: different reactivity patterns for acyclic and cyclic diamidogermylenes and -stannylenes. Dalton Trans 2013; 42:3835-42. [DOI: 10.1039/c2dt32443a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Malcolm AC, Sabourin KJ, McDonald R, Ferguson MJ, Rivard E. Donor–Acceptor Complexation and Dehydrogenation Chemistry of Aminoboranes. Inorg Chem 2012; 51:12905-16. [DOI: 10.1021/ic3018997] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Adam C. Malcolm
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta,
Canada T6G 2G2
| | - Kyle J. Sabourin
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta,
Canada T6G 2G2
| | - Robert McDonald
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta,
Canada T6G 2G2
| | - Michael J. Ferguson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta,
Canada T6G 2G2
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta,
Canada T6G 2G2
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Al-Rafia SMI, McDonald R, Ferguson MJ, Rivard E. Preparation of Stable Low-Oxidation-State Group 14 Element Amidohydrides and Hydride-Mediated Ring-Expansion Chemistry of N-Heterocyclic Carbenes. Chemistry 2012; 18:13810-20. [DOI: 10.1002/chem.201202195] [Citation(s) in RCA: 126] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Indexed: 11/07/2022]
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