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Ževart T, Pinter B, Lozinšek M, Urankar D, Jansen-van Vuuren RD, Košmrlj J. Towards structurally versatile mesoionic N-heterocyclic olefin ligands and their coordination to palladium, gold, and boron hydride. Dalton Trans 2024; 53:8915-8925. [PMID: 38590282 DOI: 10.1039/d4dt00195h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
We have developed an efficient and versatile approach for the synthesis of a family of 1,2,3-triazole-based mesoionic N-heterocyclic olefin (mNHO) ligands and investigated their coordination to palladium, gold, and boron hydride experimentally and computationally. We reacted mNHOs obtained through deprotonation of the corresponding methylated and ethylated 1,3,4-triaryl-1,2,3-triazolium salts with [Pd(allyl)Cl]2 to give the corresponding [Pd(η3-allyl)Cl(mNHO)] coordination complexes. 13C NMR data revealed the strong σ-donor character of the mNHO ligands, consistent with the calculated bond orders and atom-condensed charges. Furthermore, we also synthesized [AuCl(mNHO)] and a BH3-mNHO adduct by reacting the triazolium salts with AuCl(SMe2) and BH3·THF, respectively. The BH3-mNHO adduct was tested in the reduction of select aldehydes and ketones to alcohols.
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Affiliation(s)
- Tisa Ževart
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI 1000 Ljubljana, Slovenia.
| | - Balazs Pinter
- The University of Texas at El Paso, 500 West University Avenue, El Paso, TX 79968, USA
| | - Matic Lozinšek
- Jožef Stefan Institute, Jamova cesta 39, SI 1000 Ljubljana, Slovenia
| | - Damijana Urankar
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI 1000 Ljubljana, Slovenia.
| | - Ross D Jansen-van Vuuren
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI 1000 Ljubljana, Slovenia.
| | - Janez Košmrlj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI 1000 Ljubljana, Slovenia.
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2
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Medvedko S, Wagner JP. From Criegee to Breslow: How π-Donors Steer the Route of Olefin Ozonolysis. Chemistry 2024; 30:e202400026. [PMID: 38501221 DOI: 10.1002/chem.202400026] [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: 01/03/2024] [Revised: 03/16/2024] [Accepted: 03/19/2024] [Indexed: 03/20/2024]
Abstract
While π-bonds typically undergo cycloaddition with ozone, resulting in the release of much-noticed carbonyl O-oxide Criegee intermediates, lone-pairs of electrons tend to selectively accept a single oxygen atom from O3, producing singlet dioxygen. We questioned whether the introduction of potent electron-donating groups, akin to N-heterocyclic olefins, could influence the reactivity of double bonds - shifting from cycloaddition to oxygen atom transfer or generating lesser-known, yet stabilized, donor-substituted Criegee intermediates. Consequently, we conducted a comparative computational study using density functional theory on a series of model olefins with increasing polarity due to (asymmetric) π-donor substitution. Reaction path computations indicate that highly polarized double bonds, instead of forming primary ozonides in their reaction with O3, exhibit a preference for accepting a single oxygen atom, resulting in a zwitterionic species formally identified as a carbene-carbonyl adduct. This previously unexplored reactivity potentially introduces aldehyde umpolung chemistry (Breslow intermediate) through olefin ozonolysis. Considering solvent effects implicitly reveals that increased solvent polarity further directs the trajectories toward a single oxygen atom transfer reactivity by stabilizing the zwitterionic character of the transition state. The competing modes of chemical reactivity can be explained by a bifurcation of the reaction valley in the post-transition state region.
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Affiliation(s)
- Serhii Medvedko
- Institut für Organische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
- Department of Organic Chemistry, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Peremohy Ave. 37, 03056, Kyiv, Ukraine
| | - J Philipp Wagner
- Institut für Organische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
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3
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Rudolf R, Batman D, Mehner N, Walter RRM, Sarkar B. Redox-Active Triazole-Derived Mesoionic Imines with Ferrocenyl Substituents and their Metal Complexes: Directed Hydrogen-Bonding, Unusual C-H Activation and Ion-Pair Formation. Chemistry 2024:e202400730. [PMID: 38634285 DOI: 10.1002/chem.202400730] [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: 02/22/2024] [Revised: 04/17/2024] [Accepted: 04/17/2024] [Indexed: 04/19/2024]
Abstract
We present herein the synthesis, characterization and complexation of ferrocenyl-substituted MIIs (mesoionic imines) and their metal complexes. In the free MIIs, strong hydrogen bonding interactions are observed between the imine-N and the C-H bonds of the ferrocenyl substituents both in the solid state and in solution. The influence of this hydrogen bonding is so strong that complexation of the MIIs with [IrCp*Cl2]2 yields unique six-membered iridacycles via C-H-activation of the corresponding C-H-site at the Fc-substituent and not the Ph-substituent. This result is in contrast to previous reports in which always a preferential C-H activation at the phenyl substituent is observed in competitive reactions in the presence of ferrocenyl substituents. The corresponding Ir complexes formed after in-situ halide exchange reaction exist in either [Ir-I] contact or as [Ir]+I- solvent separated ion-pairs depending on the solvent polarity. The iodide coordinated and solvent separated ion-pairs display drastically different physical properties. The TEP (Tolman-electronic-parameter) of these ligands was determined and lines up with previously reported MII-ligands. The redox properties were investigated by a combination of electrochemical and spectroelectrochemical methods. We show here how non-covalent interactions can have a drastic influence on the physical and chemical properties of these new class of compounds.
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Affiliation(s)
- Richard Rudolf
- Universität Stuttgart, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569, Stuttgart
| | - Derman Batman
- Universität Stuttgart, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569, Stuttgart
| | - Niklas Mehner
- Universität Stuttgart, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569, Stuttgart
| | - Robert R M Walter
- Universität Stuttgart, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569, Stuttgart
| | - Biprajit Sarkar
- Universität Stuttgart, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569, Stuttgart
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4
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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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5
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Haug I, Reitz J, Ziane C, Buchmeiser MR, Hansmann MM, Naumann S. Mesoionic N-Heterocyclic Olefins as Initiators for the Lewis Pair Polymerization of Epoxides. Macromol Rapid Commun 2024:e2300716. [PMID: 38497903 DOI: 10.1002/marc.202300716] [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: 12/11/2023] [Revised: 03/14/2024] [Indexed: 03/19/2024]
Abstract
Mesoionic N-heterocyclic olefins (mNHOs) have recently emerged as a novel class of highly nucleophilic and super-basic σ-donor compounds. Making use of these properties in synthetic polymer chemistry, it is shown that a combination of a specific mNHO and a Mg-based Lewis acid (magnesium bis(hexamethyldisilazide), Mg(HMDS)2) delivers poly(propylene oxide) in quantitative yields from the polymerization of the corresponding epoxide (0.1 mol% mNHO loading). The initiation mechanism involves monomer activation by the Lewis acid and direct ring-opening of the monomer by nucleophilic attack of the mNHO, forming a zwitterionic propagating species. Modulation of the mNHO properties is thereby a direct tool to impact initiation efficiency, revealing a sterically unencumbered triazole-derivative as particularly useful. The joint application of mNHOs together with borane-type Lewis acids is also outlined, resulting in high conversions and fast polymerization kinetics. Importantly, while molar mass distributions remain relatively broad, indicating faster propagation than initiation, the overall molar masses are significantly lower than found in the case of regular NHOs, underlining the increased nucleophilicity and ensuing improved initiation efficiency of mNHOs.
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Affiliation(s)
- Iris Haug
- University of Stuttgart, Institute of Polymer Chemistry, 70569, Stuttgart, Germany
| | - Justus Reitz
- TU Dortmund, Faculty for Chemistry and Chemical Biology, 44227, Dortmund, Germany
| | - Célia Ziane
- University of Stuttgart, Institute of Polymer Chemistry, 70569, Stuttgart, Germany
| | - Michael R Buchmeiser
- University of Stuttgart, Institute of Polymer Chemistry, 70569, Stuttgart, Germany
| | - Max M Hansmann
- TU Dortmund, Faculty for Chemistry and Chemical Biology, 44227, Dortmund, Germany
| | - Stefan Naumann
- University of Stuttgart, Institute of Polymer Chemistry, 70569, Stuttgart, Germany
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6
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Sun Q, Eitzinger A, Esken R, Antoni PW, Mayer RJ, Ofial AR, Hansmann MM. Pyridinium-Derived Mesoionic N-Heterocyclic Olefins (py-mNHOs). Angew Chem Int Ed Engl 2024; 63:e202318283. [PMID: 38153170 DOI: 10.1002/anie.202318283] [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: 11/29/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 12/29/2023]
Abstract
Mesoionic polarization allows access to electron-rich olefins that have found application as organocatalysts, ligands, or nucleophiles. Herein, we report the synthesis and characterization of a series of 3-methylpyridinium-derived mesoionic olefins (py-mNHOs). We used a DFT-supported design concept, which showed that the introduction of aryl groups in the 1-, 2-, 4-, and 6-positions of the heterocyclic core allowed the kinetic stabilization of the novel mesoionic compounds. Tolman electronic parameters indicate that py-mNHOs are remarkably strong σ-donor ligands toward transition metals and main group Lewis acids. Additionally, they are among the strongest nucleophiles on the Mayr reactivity scale. In reactions of py-mNHOs with electron-poor π-systems, a gradual transition from the formation of zwitterionic adducts via stepwise to concerted 1,3-dipolar cycloadditions was observed experimentally and analyzed by quantum-chemical calculations.
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Affiliation(s)
- Qiu Sun
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Andreas Eitzinger
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 (Haus F), 81377, München, Germany
| | - Robin Esken
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Patrick W Antoni
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Robert J Mayer
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 Allée Gaspard Monge, 67000, Strasbourg, France
| | - Armin R Ofial
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 (Haus F), 81377, München, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
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7
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Rajendran NM, Lu Q, Bouffard J. A Facile Preparation of N-Heterocyclic Olefins: Ring-Opening Polymerization of β-Butyrolactone and Frustrated Lewis Pair Reactivity. Chemistry 2024; 30:e202303358. [PMID: 38109087 DOI: 10.1002/chem.202303358] [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: 10/12/2023] [Indexed: 12/19/2023]
Abstract
A direct synthesis of N-heterocyclic olefins (NHOs) and their mesoionic congeners (mNHOs) from N-heterocyclic carbenes and N-aziridinylimines is reported. The reaction provided diverse functionalized (m)NHOs and π-extended analogues. The prepared NHOs initiated the ring-opening polymerization of β-butyrolactone, and insertion of aldehyde and nitrile into an NHO-B(C6 F5 )3 adduct was demonstrated.
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Affiliation(s)
| | - Qi Lu
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, 03760, Korea
| | - Jean Bouffard
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, 03760, Korea
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8
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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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9
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Eitzinger A, Reitz J, Antoni PW, Mayr H, Ofial AR, Hansmann MM. Pushing the Upper Limit of Nucleophilicity Scales by Mesoionic N-Heterocyclic Olefins. Angew Chem Int Ed Engl 2023; 62:e202309790. [PMID: 37540606 DOI: 10.1002/anie.202309790] [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: 07/10/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 08/06/2023]
Abstract
A series of mesoionic, 1,2,3-triazole-derived N-heterocyclic olefins (mNHOs), which have an extraordinarily electron-rich exocyclic CC-double bond, was synthesized and spectroscopically characterized, in selected cases by X-ray crystallography. The kinetics of their reactions with arylidene malonates, ArCH=C(CO2 Et)2 , which gave zwitterionic adducts, were investigated photometrically in THF at 20 °C. The resulting second-order rate constants k2 (20 °C) correlate linearly with the reported electrophilicity parameters E of the arylidene malonates (reference electrophiles), thus providing the nucleophile-specific N and sN parameters of the mNHOs according to the correlation lg k2 (20 °C)=sN (N+E). With 21
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Affiliation(s)
- Andreas Eitzinger
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 (Haus F), 81377, München, Germany
| | - Justus Reitz
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Patrick W Antoni
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Herbert Mayr
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 (Haus F), 81377, München, Germany
| | - Armin R Ofial
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13 (Haus F), 81377, München, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
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10
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Hansmann MM. Diazoalkenes: From an Elusive Intermediate to a Stable Substance Class in Organic Chemistry. Angew Chem Int Ed Engl 2023; 62:e202304574. [PMID: 37095063 DOI: 10.1002/anie.202304574] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 04/26/2023]
Abstract
Over decades diazoalkenes (R2 C=C=N2 ) were postulated as reactive intermediates in organic chemistry even though their direct spectroscopic detection proved very challenging. In the 1970/80ies several groups probed their existence mainly indirectly by trapping experiments or directly by matrix-isolation studies. In 2021, our group and the Severin group reported independently the synthesis and characterization of the first room-temperature stable diazoalkenes, which initiated a rapidly expanding research field. Up to now four different classes of N-heterocyclic substituted room-temperature stable diazoalkenes have been reported. Their properties and unique reactivity, such as N2 /CO exchange or utilization as vinylidene precursors in organic and transition metal chemistry are presented. This review summarizes the early discoveries of diazoalkenes from their initial postulation as transient, elusive species up to the recent findings of the room-temperature stable derivatives.
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Affiliation(s)
- Max M Hansmann
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 6, Dortmund, Germany
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11
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G M, Sharma D, Dandela R, Dhayalan V. Synthetic Strategies of N-Heterocyclic Olefin (NHOs) and Their Recent Application of Organocatalytic Reactions and Beyond. Chemistry 2023:e202302106. [PMID: 37605950 DOI: 10.1002/chem.202302106] [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: 07/03/2023] [Revised: 08/21/2023] [Accepted: 08/22/2023] [Indexed: 08/23/2023]
Abstract
N-heterocyclic olefin (NHO) derivatives have an electron-rich as well as highly polarized carabon-carbon (C=C) double bond because of the electron-donating nature of nitrogen and sulphur atoms. While NHOs have been developing as novel organocatalysts and ligands for transition-metal complexes in various organic compound syntheses, different research groups are currently interested in preparing imidazole and triazolium-based chiral NHO catalysts. Some of them have been used for enantioselective organic transformations, but were still elusive. N-heterocyclic olefins, the alkylidene derivatives of N-heterocyclic carbenes (NHC), have shown promising results as effective promoters for numerous organic syntheses such as asymmetric catalysis, hydroborylation, hydrosilylation, reduction, CO2 sequestration, alkylation, cycloaddition, polymerization and the ring-opening reaction of aziridine and epoxides, esterification, C-F bond functionalization, amine coupling, trifluoromethyl thiolation, amination etc. NHOs catalysts with suitable structures can serve as a novel class of Lewis/Bronsted bases with strong basicity and high nucleophilicity properties.These facts strongly suggest their enormous chemical potential as sustainable catalysts for a wide variety of reactions in synthetic chemistry. The synthesis of NHOs and their properties are briefly reviewed in this article, along with a summary of the imidazole and triazole core of NHOs' most recent catalytic uses.
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Affiliation(s)
- Mahantesh G
- Department of Chemistry, National Institute of Technology Puducherry, Karaikal, 609609, Union Territory Puducherry, India
| | - Deepika Sharma
- Department of Industrial and Engineering Chemistry, Institute of Chemical Technology, Indian oil Odisha Campus, IIT, Kharagpur extension Centre Mouza Samantpuri, Bhubaneswar, 751013, Odisha, India
| | - Rambabu Dandela
- Department of Industrial and Engineering Chemistry, Institute of Chemical Technology, Indian oil Odisha Campus, IIT, Kharagpur extension Centre Mouza Samantpuri, Bhubaneswar, 751013, Odisha, India
| | - Vasudevan Dhayalan
- Department of Chemistry, National Institute of Technology Puducherry, Karaikal, 609609, Union Territory Puducherry, India
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12
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Nakata M, Hirashita T, Konishi Y, Araki S. Synthesis of stable class 5 mesoionic benzo[ c]tetrazolo[2,3- a]cinnolinium thiolate, dicyanomethylide, and amides. Org Biomol Chem 2023; 21:4282-4289. [PMID: 37158001 DOI: 10.1039/d3ob00362k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Although class 5 mesoionic compounds show interesting electrical behaviour, they are generally unstable, readily undergoing ring-opening reactions. We designed and synthesized a bridged mesoionic derivative, benzo[c]tetrazolo[2,3-a]cinolinium (BTC), as a stable class 5 mesoionic compound, which was further transformed to the corresponding thiolate, cicyanomethylide, and amide. The intramolecular bridging imparted stability to the BTC thiolates and amides: the BTC thiolates were unsusceptible to ring-opening at high temperatures, and the BTC amides were stable in the absence of electron-withdrawing groups on the amide nitrogen. The properties of the BTC thiolate were compared with those of 2,3-diphenyltetrazolium derivatives based on UV-Vis absorption spectroscopy, single-crystal X-ray diffraction and quantum calculations.
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Affiliation(s)
- Mirai Nakata
- Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
| | - Tsunehisa Hirashita
- Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
| | - Yoshikazu Konishi
- Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
| | - Shuki Araki
- Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
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13
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Kooij B, Varava P, Fadaei-Tirani F, Scopelliti R, Pantazis DA, Van Trieste GP, Powers DC, Severin K. Copper Complexes with Diazoolefin Ligands and their Photochemical Conversion into Alkenylidene Complexes. Angew Chem Int Ed Engl 2023; 62:e202214899. [PMID: 36445783 DOI: 10.1002/anie.202214899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/28/2022] [Accepted: 11/28/2022] [Indexed: 11/30/2022]
Abstract
Homometallic copper complexes with alkenylidene ligands are discussed as intermediates in catalysis but the isolation of such complexes has remained elusive. Herein, we report the structural characterization of copper complexes with bridging and terminal alkenylidene ligands. The compounds were obtained by irradiation of CuI complexes with N-heterocyclic diazoolefin ligands. The complex with a terminal alkenylidene ligand required isolation in a crystalline matrix, and its structural characterization was enabled by in crystallo photolysis at low temperature.
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Affiliation(s)
- Bastiaan Kooij
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Paul Varava
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | | | | | - David C Powers
- Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
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14
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Das A, Sarkar P, Maji S, Pati SK, Mandal SK. Mesoionic N-Heterocyclic Imines as Super Nucleophiles in Catalytic Couplings of Amides with CO 2. Angew Chem Int Ed Engl 2022; 61:e202213614. [PMID: 36259383 DOI: 10.1002/anie.202213614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Indexed: 11/07/2022]
Abstract
An extended class of stable mesoionic N-heterocyclic imines (mNHIs), containing a highly polarized exocyclic imine moiety, were synthesized. The calculated proton affinities (PA) and experimentally determined Tolman electronic parameters (TEPs) reveal that these synthesized mNHIs have the highest basicity and donor ability among NHIs reported so far. The superior nucleophilicity of newly designed mNHIs was utilized in devising a strategy to incorporate CO2 as a bridging unit under reductive conditions to couple inert primary amides. This strategy was further extended to hetero-couplings between amide and amine using CO2 . These hitherto unknown catalytic transformations were introduced in the diversification of various biologically active drug molecules under metal-free conditions. The underlying mechanism was explored by performing a series of control experiments, characterizing key intermediates using spectroscopic and crystallographic techniques.
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Affiliation(s)
- Arpan Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, Nadia, India
| | - Pallavi Sarkar
- Department Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, 560064, India
| | - Subir Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, Nadia, India
| | - Swapan K Pati
- Department Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, 560064, India
| | - Swadhin K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, Nadia, India
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15
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Abstract
This Perspective article highlights the recent development of mesoionic N-heterocyclic olefins (mNHOs), where the exo-cyclic olefinic carbon is not bonded to strongly electron-withdrawing groups. The unquenched basicity and nucleophilicity of the exo-cyclic olefinic carbon make mNHOs strong σ-donors and enable unique reactivity patterns.
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Affiliation(s)
- Qiuming Liang
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6.
| | - Datong Song
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6.
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16
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Rudolf R, Neuman NI, Walter RRM, Ringenberg MR, Sarkar B. Mesoionic Imines (MIIs): Strong Donors and Versatile Ligands for Transition Metals and Main Group Substrates. Angew Chem Int Ed Engl 2022; 61:e202200653. [PMID: 35286004 PMCID: PMC9322014 DOI: 10.1002/anie.202200653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Indexed: 11/08/2022]
Abstract
We report the synthesis and the reactivity of 1,2,3‐triazolin‐5‐imine type mesoionic imines (MIIs). The MIIs are accessible by a base‐mediated cycloaddition between a substituted acetonitrile and an aromatic azide, methylation by established routes and subsequent deprotonation. C=O‐stretching frequencies in MII−CO2 and −Rh(CO)2Cl complexes were used to determine the overall donor strength. The MIIs are stronger donors than the N‐heterocyclic imines (NHIs). MIIs are excellent ligands for main group elements and transition metals in which they display substituent‐induced fluorine‐specific interactions and undergo C−H activation. DFT calculations gave insights into the frontier orbitals of the MIIs. The calculations predict a relatively small HOMO–LUMO gap compared to other related ligands. MIIs are potentially able to act as both π‐donor and π‐acceptor ligands. This report highlights the potential of MIIs to display exciting properties with a huge potential for future development.
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Affiliation(s)
- Richard Rudolf
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Nicolás I. Neuman
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
- Instituto de Desarrollo Tecnológico para la Industria Química INTEC, UNL-CONICET Predio CONICET Santa Fe “Dr. Alberto Cassano” Colectora Ruta Nacional 168, Km 0 Paraje El Pozo S3000ZAA) Santa Fe Argentina
| | - Robert R. M. Walter
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Mark. R. Ringenberg
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
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17
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Qu ZW, Zhu H, Streubel R, Grimme S. Catalytic Isomerization of Unprotected Mesoionic N‐heterocyclic Olefins and Their Lewis Adducts. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Zheng-Wang Qu
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Mulliken Center for Theoretical Chemistry Beringstr. 4 D-53115 Bonn GERMANY
| | - Hui Zhu
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Mulliken Center for Theoretical Chemistry Bonn GERMANY
| | - Rainer Streubel
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Institut für Anorganische Chemie Bonn GERMANY
| | - Stefan Grimme
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Mulliken Center for Theoretical Chemistry Bonn GERMANY
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18
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Huang S, Wu Y, Huang L, Hu C, Yan X. Synthesis, Characterization and Photophysical Properties of Mesoionic N-Heterocyclic Imines. Chem Asian J 2022; 17:e202200281. [PMID: 35502454 DOI: 10.1002/asia.202200281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/19/2022] [Indexed: 11/09/2022]
Abstract
N -heterocyclic imines are widely used in transition-metal chemistry, main-group chemistry as well as catalysis, due to their enhanced basicity and nucleophilicity which benefit from their ylidic form. As their analogs, mesoionic N -heterocyclic imines, which feature more highly ylidic form, is still in its infancy though excellent works also achieved. Here we reported the synthesis, characterization and photophysical properties of mesoionic N -heterocyclic imines. TD-DFT are employed to get deeper insight into the mechanism of the photophysical behaviors. The unsubstituted mesoionic N-heterocyclic imines ( 1-3 ) displayed considerable quantum yields (QY: up to 43.8%) and could be potentially applied as luminescent materials.
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Affiliation(s)
| | - Yixin Wu
- Renmin University of China, Chemistry, CHINA
| | | | - Chubin Hu
- Renmin University of China, Chemistry, CHINA
| | - Xiaoyu Yan
- Renmin University of China, Department of Chemistry, Renmin University of China, Beijing 100872, China, 100872, Beijing, CHINA
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19
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Qu ZW, Zhu H, Streubel R, Grimme S. C‐H Deprotonation and C=C Hydrogenation of N‐heterocyclic Olefin with Calcium Hydride Complexes: Cooperative Ca‐H‐Ca Bridge versus Terminal Ca‐H bond. ChemCatChem 2022. [DOI: 10.1002/cctc.202200508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Zheng-Wang Qu
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Mulliken Center for Theoretical Chemistry Beringstr. 4 D-53115 Bonn GERMANY
| | - Hui Zhu
- Rheinische Friedrich-Wilhelms-Universitat Bonn Mulliken Center for Theoretical Chemsitry Bonn GERMANY
| | - Rainer Streubel
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Institut für Anorganische Chemie Bonn GERMANY
| | - Stefan Grimme
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Mulliken Center for Theoretical Chemistry Bonn GERMANY
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20
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Rudolf R, Neuman NI, Walter RRM, Ringenberg MR, Sarkar B. Mesoionische Imine (MIIs): Starke Donoren und vielseitige Liganden für Übergangsmetalle und Hauptgruppensubstrate. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Richard Rudolf
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Nicolás I. Neuman
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
- Instituto de Desarrollo Tecnológico para la Industria Química CINTEC, VUNL-CONICET VPredio CONICET Santa Fe “Dr. Alberto Cassano“ Colectora Ruta Nacional 168, Km 0 Paraje El Pozo S3000ZAA) Santa Fe Argentinien
| | - Robert R. M. Walter
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Mark. R. Ringenberg
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
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21
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Kooij B, Dong Z, Varava P, Fadaei-Tirani F, Scopelliti R, Piveteau L, Severin K. Vanadium complexes with N-heterocyclic vinylidene ligands. Chem Commun (Camb) 2022; 58:4204-4207. [PMID: 35274647 DOI: 10.1039/d2cc00768a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The preparation and the structural characterization of vanadium complexes with terminal and bridging N-heterocyclic vinylidene ligands is reported. The synthesis of the complexes was enabled by utilization of diazoolefins as ligand precursors. Structural data and theoretical results show that N-heterocyclic vinylidenes can act as 6e- donor ligands, leading to strong metal-carbon interactions.
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Affiliation(s)
- Bastiaan Kooij
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Zhaowen Dong
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Paul Varava
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Laura Piveteau
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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22
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Maity R, Sarkar B. Chemistry of Compounds Based on 1,2,3-Triazolylidene-Type Mesoionic Carbenes. JACS AU 2022; 2:22-57. [PMID: 35098220 PMCID: PMC8790748 DOI: 10.1021/jacsau.1c00338] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Indexed: 05/04/2023]
Abstract
Mesoionic carbenes (MICs) of the 1,2,3-triazolylidene type have established themselves as a popular class of compounds over the past decade. Primary reasons for this popularity are their modular synthesis and their strong donor properties. While such MICs have mostly been used in combination with transition metals, the past few years have also seen their utility together with main group elements. In this paper, we present an overview of the recent developments on this class of compounds that include, among others, (i) cationic and anionic MIC ligands, (ii) the donor/acceptor properties of these ligands with a focus on the several methods that are known for estimating such donor/acceptor properties, (iii) a detailed overview of 3d metal complexes and main group compounds with these MIC ligands, (iv) results on the redox and photophysical properties of compounds based on MIC ligands, and (v) an overview on electrocatalysis, redox-switchable catalysis, and small-molecule activation to highlight the applications of compounds based on MIC ligands in contemporary chemistry. By discussing several aspects from the synthetic, spectroscopic, and application point of view of these classes of compounds, we highlight the state of the art of compounds containing MICs and present a perspective for future research in this field.
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Affiliation(s)
- Ramananda Maity
- Dr.
R. Maity Department of Chemistry, University
of Calcutta, 92, A. P.
C. Road, Kolkata 700009, India
| | - Biprajit Sarkar
- Prof.
Dr. B. Sarkar Lehrstuhl für Anorganische Koordinationschemie,
Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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23
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Merschel A, Vishnevskiy YV, Neumann B, Stammler G, Ghadwal RS. Crystalline phosphino-functionalized mesoionic olefins (p-MIOs). Dalton Trans 2022; 51:8217-8222. [DOI: 10.1039/d2dt01314b] [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
Phosphino-functionalized mesoionic olefins (p-MIOs), (iMIC)CHR (iMIC = PhC{N(Dipp)}2C(PPh2)C, Dipp = 2,6-iPr2C6H3; R = H 4a or Ph 4b) derived from a 1,3-imidazole based mesoionic carbene (iMIC) are reported. The p-MIOs...
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24
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Kutin Y, Reitz J, Antoni PW, Savitsky A, Pantazis DA, Kasanmascheff M, Hansmann MM. Characterization of a Triplet Vinylidene. J Am Chem Soc 2021; 143:21410-21415. [PMID: 34898204 PMCID: PMC8704171 DOI: 10.1021/jacs.1c11062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
![]()
Singlet vinylidenes
(R2C=C:) are proposed as
intermediates in a series of organic reactions, and very few have
been studied by matrix isolation or gas-phase spectroscopy. Triplet
vinylidenes, however, featuring two unpaired electrons at a monosubstituted
carbon atom are thus far only predicted as electronically excited-state
species and represent an unexplored class of carbon-centered diradicals.
We report the photochemical generation and low-temperature EPR/ENDOR
characterization of the first ground-state high-spin (triplet) vinylidene.
The zero-field splitting parameters (D = 0.377 cm–1 and |E|/D = 0.028)
were determined, and the 13C hyperfine coupling tensor
was obtained by 13C-ENDOR measurements. Most strikingly,
the isotropic 13C hyperfine coupling constant (50 MHz)
is far smaller than the characteristic values of triplet carbenes,
demonstrating a unique electronic structure which is supported by
quantum chemical calculations.
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Affiliation(s)
- Yury Kutin
- Department of Chemistry and Chemical Biology, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Justus Reitz
- Department of Chemistry and Chemical Biology, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Patrick W Antoni
- Department of Chemistry and Chemical Biology, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Anton Savitsky
- Department of Physics, Technische Universität Dortmund, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Müge Kasanmascheff
- Department of Chemistry and Chemical Biology, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Max M Hansmann
- Department of Chemistry and Chemical Biology, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
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25
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Hu C, Huang S, Zhang Z, Yao H, Wu Y, Huang L, Yan X. Experimental and Computational Study on Photophysical Properties of Mesoionic Chalcogenones. Chem Asian J 2021; 16:4165-4170. [PMID: 34729937 DOI: 10.1002/asia.202101157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/30/2021] [Indexed: 12/14/2022]
Abstract
N-Heterocyclic carbene adducts with main group elements (NHC=E) have aroused great interest and have been widely investigated in coordination chemistry. Among them, N-heterocyclic carbene adducts with chalcogens (NHC=Ch) have been known for a long time. Their investigations mostly focused on synthesis, coordination chemistry and electrochemistry. Their photophysical properties still remain unexplored. In this work, the photophysical properties of mesoionic carbene adducts with sulfur and selenium have been investigated both in solution and solid state. These compounds showed blue fluorescence in dichloromethane. While in solid state, orange to red room-temperature phosphorescence can be observed, and dual emission was found in mesoionic thiones. Furthermore, time-dependent density functional theory (TD-DFT) calculations were used to obtain insights into the luminescent mechanism.
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Affiliation(s)
- Chubin Hu
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Shiqing Huang
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Zengyu Zhang
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Haidan Yao
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Yixin Wu
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Linwei Huang
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Xiaoyu Yan
- Key Laboratory of Advanced Light Conversion Materials and Biophotonics, Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
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26
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Liang Q, Hayashi K, Li L, Song D. Dioxygenation of unprotected mesoionic N-heterocyclic olefins. Chem Commun (Camb) 2021; 57:10927-10930. [PMID: 34596194 DOI: 10.1039/d1cc04695k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We report the dioxygenation of mesoionic N-heterocyclic olefins (mNHOs) using molecular dioxygen. For 1,2,3-triazole-derived mNHOs possessing a vinyl proton and at least one acidic C-H group, they are oxidized into the corresponding triazolium benzoate salts, whereas those without vinyl proton or an acidic C-H group are oxidized into triazolium oxide and ketones/aldehydes.
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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.
| | - Longfei Li
- College of Pharmacy, Hebei University, Baoding 071002, Hebei, P. R. China
| | - 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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27
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Dubey G, Awari S, Singh T, Sahoo SC, Bharatam PV. Mesoionic and N-Heterocyclic Carbenes Coordinated N + Center: Experimental and Computational Analysis. Chempluschem 2021; 86:1416-1420. [PMID: 34636173 DOI: 10.1002/cplu.202100281] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/17/2021] [Indexed: 11/07/2022]
Abstract
N-Heterocyclic carbenes, carbocyclic carbenes, remote N-heterocyclic carbenes and N-heterocyclic silylenes are known to form L→N+ coordination bonds. However, mesoionic carbenes (MICs) are not reported to form coordination bonds with cationic nitrogen. Herein, synthesis and quantum chemical studies were performed on 1,2,3-triazol-5-ylidene stabilized N+ center. Six compounds with MIC→N+ ←NHC were synthesized. Density functional theory calculations and energy decomposition analysis were carried out to explore the bonding situation between MIC and N+ center. The C→N+ bond lengths were in the range of 1.295-1.342 Å and bond dissociation energies were <400 kcal/mol. Natural bond orbital analysis supported the presence of excess electron density (>3 electrons) at the N+ center. The computational and X-ray diffraction analysis results confirmed the presence of divalent NI character of center nitrogen and MIC→N+ ←NHC coordination interactions.
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Affiliation(s)
- Gurudutt Dubey
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, 160062, Punjab, India
| | - Shruti Awari
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, 160062, Punjab, India
| | - Tejender Singh
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, 160062, Punjab, India
| | - Subash C Sahoo
- Department of Chemistry, Panjab University, Sector 14, Chandigarh, 160014, India
| | - Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, 160062, Punjab, India
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28
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Maji S, Das A, Mandal SK. Mesoionic N-heterocyclic olefin catalysed reductive functionalization of CO 2 for consecutive N-methylation of amines. Chem Sci 2021; 12:12174-12180. [PMID: 34667583 PMCID: PMC8457391 DOI: 10.1039/d1sc02819g] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 08/02/2021] [Indexed: 11/21/2022] Open
Abstract
A mesoionic N-heterocyclic olefin (mNHO) was introduced as a metal-free catalyst for the reductive functionalization of CO2 leading to consecutive double N-methylation of primary amines in the presence of 9-borabicyclo[3.3.1]nonane (9-BBN). A wide range of secondary amines and primary amines were successfully methylated under mild conditions. The catalyst sustained over six successive cycles of N-methylation of secondary amines without compromising its activity, which encouraged us to check its efficacy towards double N-methylation of primary amines. Moreover, this method was utilized for the synthesis of two commercially available drug molecules. A detailed mechanistic cycle was proposed by performing a series of control reactions along with the successful characterisation of active catalytic intermediates either by single-crystal X-ray study or by NMR spectroscopic studies in association with DFT calculations.
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Affiliation(s)
- Subir Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata Mohanpur-741246 India
| | - Arpan Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata Mohanpur-741246 India
| | - Swadhin K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata Mohanpur-741246 India
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29
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Kundu A, Chandra S, Mandal D, Neuman NI, Mahata A, Anga S, Rawat H, Pal S, Schulzke C, Sarkar B, Chandrasekhar V, Jana A. Twisted Push-Pull Alkenes Bearing Geminal Cyclicdiamino and Difluoroaryl Substituents. J Org Chem 2021; 86:12683-12692. [PMID: 34473501 DOI: 10.1021/acs.joc.1c01201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The systematic combination of N-heterocyclic olefins (NHOs) with fluoroarenes resulted in twisted push-pull alkenes. These alkenes carry electron-donating cyclicdiamino substituents and two electron-withdrawing fluoroaryl substituents in the geminal positions. The synthetic method can be extended to a variety of substituted push-pull alkenes by varying the NHO as well as the fluoroarenes. Solid-state molecular structures of these molecules reveal a notable elongation of the central C-C bond and a twisted geometry in the alkene motif. Absorption properties were investigated with UV-vis spectroscopy. The redox properties of the twisted push-pull alkenes were probed with electrochemistry as well as UV-vis/NIR and EPR spectroelectrochemistry, while the electronic structures were computationally evaluated and validated.
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Affiliation(s)
- Abhinanda Kundu
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Shubhadeep Chandra
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Debdeep Mandal
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Nicolás I Neuman
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.,Instituto de Desarrollo Tecnológico para la Industria Química, CCT Santa Fe CONICET-UNL, Colectora Ruta Nacional 168, Paraje El Pozo, 3000 Santa Fe, Argentina
| | - Alok Mahata
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Srinivas Anga
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Hemant Rawat
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Sudip Pal
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489 Greifswald, Germany
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | | | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
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30
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Abstract
Structurally authenticated free B-alkyl boroles are presented and electronic implications of alkyl substitution were assessed. Deprotonation of a boron-bound exocyclic methyl group in a B-methyl borole yields the first 5-boratafulvene anion-an isomer to boratabenzene. Boratafulvene was structurally characterized and its electronic structure probed by DFT calculations. The pKa value of the exocyclic B-CH3 in a set of boroles was computationally approximated and confirmed a pronounced acidic character caused by the boron atom embedded in an anti-aromatic moiety. The non-aromatic boratafulvene reacts as a C-centered nucleophile with the mild electrophile Me3 SnCl to give a stannylmethyl borole, regenerating the anti-aromaticity. As nucleophilic synthons for boroles, boratafulvenes thus open an entirely new avenue for synthetic strategies toward this highly reactive class of heterocycles. Boratafulvene reacts as a methylene transfer reagent in a bora-Wittig-type reaction generating a borole oxide.
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Affiliation(s)
- Tobias Heitkemper
- Institut für Anorganische ChemieGeorg-August-Universität GöttingenTammannstrasse 437077GöttingenGermany
| | - Leonard Naß
- Institut für Anorganische ChemieGeorg-August-Universität GöttingenTammannstrasse 437077GöttingenGermany
| | - Christian P. Sindlinger
- Institut für Anorganische ChemieGeorg-August-Universität GöttingenTammannstrasse 437077GöttingenGermany
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31
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Heitkemper T, Naß L, Sindlinger CP. Ein Boratafulven. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Tobias Heitkemper
- Institut für Anorganische Chemie Georg-August-Universität Göttingen Tammannstraße 4 37077 Göttingen Deutschland
| | - Leonard Naß
- Institut für Anorganische Chemie Georg-August-Universität Göttingen Tammannstraße 4 37077 Göttingen Deutschland
| | - Christian P. Sindlinger
- Institut für Anorganische Chemie Georg-August-Universität Göttingen Tammannstraße 4 37077 Göttingen Deutschland
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32
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Antoni PW, Reitz J, Hansmann MM. N 2/CO Exchange at a Vinylidene Carbon Center: Stable Alkylidene Ketenes and Alkylidene Thioketenes from 1,2,3-Triazole Derived Diazoalkenes. J Am Chem Soc 2021; 143:12878-12885. [PMID: 34348463 DOI: 10.1021/jacs.1c06906] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We present a new class of room-temperature stable diazoalkenes featuring a 1,2,3-triazole backbone. Dinitrogen of the diazoalkene moiety can be thermally displaced by an isocyanide and carbon monoxide. The latter alkylidene ketenes are typically considered as highly reactive compounds, traditionally only accessible by flash vacuum pyrolysis. We present a new and mild synthetic approach to the first structurally characterized alkylidene ketenes by a substitution reaction. Density functional theory calculations suggest the substitution with isocyanides to take place via a stepwise addition/elimination mechanism. In the case of carbon monoxide, the reaction proceeds through an unusual concerted exchange at a vinylidene carbon center. The vinylidene ketenes react with carbon disulfide via a four-membered thiete intermediate to give vinylidene thioketenes under release of COS. We present spectroscopic as well as structural data for the complete isoelectronic series (R2C═C═X; X = N2, CO, CNR, CS) including 1J(13C-13C) data. As N2, CO, and isocyanides belong to the archetypical ligands in transition-metal chemistry, this process can be interpreted in analogy to coordination chemistry as a ligand exchange reaction at a vinylidene carbon center.
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Affiliation(s)
- Patrick W Antoni
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Justus Reitz
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
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33
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Huang S, Wang Y, Hu C, Yan X. Nucleophilic Activation of Sulfur Hexafluoride by N-Heterocyclic Carbenes and N-Heterocyclic Olefins: A Computational Study. Chem Asian J 2021; 16:2687-2693. [PMID: 34320272 DOI: 10.1002/asia.202100770] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/26/2021] [Indexed: 11/10/2022]
Abstract
Sulfur hexafluoride (SF6 ) is considered as a potent greenhouse gas, whose effective degradation is challenging. Here we report a computational study on the nucleophilic activation of sulfur hexafluoride by N-heterocyclic carbenes and N-heterocyclic olefins. The result shows that the activation of SF6 is both thermodynamically and kinetically favorable at mild condition using NHOs with fluoro-substituted azolium and sulfur pentafluoride anion being formed. The Gibbs free energy barrier during the activation of SF6 has a linear relationship with the energy of HOMO of substrates, which could be a guideline for applying those compounds that feature higher energy in HOMO to activate SF6 in high efficiency.
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Affiliation(s)
- Shiqing Huang
- Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Yedong Wang
- Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Chubin Hu
- Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
| | - Xiaoyu Yan
- Department of Chemistry, Renmin University of China, Beijing, 100872, P. R. China
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34
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Abstract
AbstractBased on structures determined by X-ray crystallography, ab initio MP2 calculations on type A mesoionic rings give geometries in good agreement with observed values. A study of four mesoionic ring systems, each with exocyclic oxygen, nitrogen or carbon groups, shows that the presence and configuration of exocyclic lone pairs significantly influences the geometry and configurational preference. Using a localised bond model and NBO analysis, these effects are rationalised in terms of an anomeric interaction of lone pairs with the antibonding orbitals of adjacent σ bonds. In agreement with experiment, similar effects are calculated for pyran-2-imines.
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35
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Liang Q, Hayashi K, Zeng Y, Jimenez-Santiago JL, Song D. Constructing fused N-heterocycles from unprotected mesoionic N-heterocyclic olefins and organic azides via diazo transfer. Chem Commun (Camb) 2021; 57:6137-6140. [PMID: 34042131 DOI: 10.1039/d1cc02245h] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mesoionic N-heterocyclic olefins (mNHOs) were first reported last year and their reactivity remains largely unexplored. Herein we report the reaction of unprotected mNHOs and organic azides as a novel synthetic route to a variety of pyrazolo[3,4-d][1,2,3]triazoles, an important structural motif in drug candidates and energetic materials. The only byproduct aniline can be easily recycled and converted back to the starting organic azide, in compliance with the green chemistry principle. The reaction mechanism has been explored through experimental and computational studies.
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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.
| | - Yimin Zeng
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
| | - Jose L Jimenez-Santiago
- 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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36
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Mono‐ and Di‐Mesoionic Carbene‐Boranes: Synthesis, Structures and Utility as Reducing Agents. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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37
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Isolation and reactivity of an elusive diazoalkene. Nat Chem 2021; 13:587-593. [PMID: 33927373 DOI: 10.1038/s41557-021-00675-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 03/05/2021] [Indexed: 01/05/2023]
Abstract
Most functional groups, especially those consisting of the abundant elements of organic matter-carbon, nitrogen and oxygen-have been extensively studied and only very few remain speculative due to their high intrinsic reactivity. In contrast to the well-explored chemistry of diazoalkanes (R2C=N2), diazoalkenes (R2C=C=N2) have been postulated in several organic transformations, but remain elusive long-sought intermediates. Here, we present a room-temperature stable diazoalkene, utilizing a dinitrogen transfer from nitrous oxide. This functional group shows dual-site nucleophilicity (C and N atoms) and features a bent C-C-N entity (124°) and a long N-N bond together with a remarkable low infrared absorption (1,944 cm-1). Substitution of N2 by an isocyanide leads to a vinylidene ketenimine. Furthermore, photochemically triggered loss of dinitrogen might proceed through a transient triplet vinylidene. We anticipate the existence of a stable diazoalkene functional group to pave an exciting avenue into the chemistry of low-valent carbon and unsaturated carbenes.
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38
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Sawaguchi D, Hayakawa S, Sakuma M, Niitsuma K, Kase D, Michii S, Ozawa M, Sakai Y, Sakamaki K, Ueyama K, Haraguchi R. Improved Synthesis of 1,2,3‐Triazolium Salts via Oxidative [3+2] Cycloaddition of Triazenes with Alkynes and Their Deprotonative Functionalization. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Daiki Sawaguchi
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Shunsuke Hayakawa
- Department of Applied Chemistry Graduate School of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Masaaki Sakuma
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Kenta Niitsuma
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Daiya Kase
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Shota Michii
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Miyuki Ozawa
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Yusuke Sakai
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Kentaro Sakamaki
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Kyohei Ueyama
- Department of Applied Chemistry Graduate School of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
| | - Ryosuke Haraguchi
- Department of Applied Chemistry Faculty of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
- Department of Applied Chemistry Graduate School of Engineering Chiba Institute of Technology 2-17-1 Tsudanuma Narashino, Chiba 275-0016 Japan
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39
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Gupta P, Siewert JE, Wellnitz T, Fischer M, Baumann W, Beweries T, Hering-Junghans C. Reactivity of phospha-Wittig reagents towards NHCs and NHOs. Dalton Trans 2021; 50:1838-1844. [PMID: 33471018 DOI: 10.1039/d1dt00071c] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Phospha-Wittig reagents, RPPMe3 (R = Mes* 2,4,6-tBu3-C6H2; MesTer 2,6-(2,4,6-Me3C6H2)-C6H3; DipTer 2,6-(2,6-iPr2C6H3)-C6H3), can be considered as phosphine-stabilized phosphinidenes. In this study we show that PMe3 can be displaced by NHCs or NHOs. Interestingly, phosphinidene-like reactivity results in a subsequent C(sp2)-H activation of the exocyclic CH2 group in NHOs. This concept was further extended to allyl-apended NHOs, which resulted in phosphine-substituted allyl species.
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Affiliation(s)
- Priyanka Gupta
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
| | - Jan-Erik Siewert
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
| | - Tim Wellnitz
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
| | - Malte Fischer
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
| | - Wolgang Baumann
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
| | - Torsten Beweries
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
| | - Christian Hering-Junghans
- Leibniz-Institut für Katalyse e.V. (LIKAT Rostock), Albert-Einstein-Straße 29a, 18059 Rostock, Germany.
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40
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Guthardt R, Bruhn C, Siemeling U. N-heterocyclic olefins as dative carbon donor ligands for diaminoplumbylenes: Syntheses and crystal structures of adducts with 1,3,4,5-tetramethyl-2-methyleneimidazoline. Polyhedron 2021. [DOI: 10.1016/j.poly.2020.114959] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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41
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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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42
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Wang Z, Niu QH, Xue XS, Ji P. The Brönsted Basicities of N-Heterocyclic Olefins in DMSO: An Effective Way to Evaluate the Stability of NHO-CO 2 Adducts. J Org Chem 2020; 85:13204-13210. [PMID: 32900190 DOI: 10.1021/acs.joc.0c01987] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A Brönsted basicity scale (∼24 pK units) for 85 commonly seen imidazole-, imidazoline-, triazole-, and thiazole-based N-heterocyclic olefins (NHOs) in DMSO was established using a well-examined computational model. The influence of substituents on the Brönsted basicities of these NHOs was investigated through basicity comparisons and rationalized by geometric analyses. The Gibbs energy (ΔGr) of the reaction between NHO and CO2 was also calculated, which linearly correlates with the basicity of the corresponding NHO, suggesting that the stability of NHO-CO2 adducts can be evaluated by the basicity of NHOs and a stronger basicity leads to a more stable NHO-CO2 adduct.
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Affiliation(s)
- Zhen Wang
- Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China
| | - Qian-Hang Niu
- Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China
| | - Xiao-Song Xue
- Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China.,State Key Laboratory on Elemento-Organic Chemistry, Department of Chemistry, Nankai University, Tianjin 300071, China
| | - Pengju Ji
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
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43
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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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44
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Wang D, He Y, Dai H, Huang C, Yuan X, Xie J. Manganese‐Catalyzed
Hydrocarbofunctionalization of Internal Alkenes
†. CHINESE J CHEM 2020. [DOI: 10.1002/cjoc.202000376] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dongping Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University Nanjing Jiangsu 210023 China
| | - Yijie He
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University Nanjing Jiangsu 210023 China
| | - Haotian Dai
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University Nanjing Jiangsu 210023 China
| | - Congcong Huang
- School of Chemistry and Chemical Engineering, Qufu Normal University Qufu Shandong 273165 China
| | - Xiang‐Ai Yuan
- School of Chemistry and Chemical Engineering, Qufu Normal University Qufu Shandong 273165 China
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University Nanjing Jiangsu 210023 China
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45
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Delaude L. The Chemistry of Azolium‐Carboxylate Zwitterions and Related Compounds: a Survey of the Years 2009–2020. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000639] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Lionel Delaude
- Laboratory of CatalysisMolSys Research UnitInstitut de Chimie Organique (B6a)Université de Liège Allée du six Août 13 4000 Liège Belgium
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46
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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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