1
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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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2
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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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3
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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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4
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Das M, Hogan C, Zielinski R, Kubicki M, Koy M, Kosbab C, Brozzesi S, Das A, Nehring MT, Balfanz V, Brühne J, Dähne M, Franz M, Esser N, Glorius F. N-Heterocyclic Olefins on a Silicon Surface. Angew Chem Int Ed Engl 2023; 62:e202314663. [PMID: 37849449 DOI: 10.1002/anie.202314663] [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: 07/05/2023] [Revised: 10/13/2023] [Accepted: 10/17/2023] [Indexed: 10/19/2023]
Abstract
The adsorption of N-heterocyclic olefins (NHOs) on silicon is investigated in a combined scanning tunneling microscopy, X-ray photoelectron spectroscopy, and density functional theory study. We find that both of the studied NHOs bind covalently, with ylidic character, to the silicon adatoms of the substrate and exhibit good thermal stability. The adsorption geometry strongly depends on the N-substituents: for large N-substituents, an upright adsorption geometry is favored, while a flat-lying geometry is found for the NHO with smaller wingtips. These different geometries strongly influence the quality and properties of the obtained monolayers. The upright geometry leads to the formation of ordered monolayers, whereas the flat-lying NHOs yield a mostly disordered, but denser, monolayer. The obtained monolayers both show large work function reductions, as the higher density of the flat-lying monolayer is found to compensate for the smaller vertical dipole moments. Our findings offer new prospects in the design of tailor-made ligand structures in organic electronics and optoelectronics, catalysis, and material science.
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Affiliation(s)
- Mowpriya Das
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
| | - Conor Hogan
- Istituto di Struttura della Materia-CNR (ISM-CNR), Via del Fosso del Cavaliere 100, 00133, Rome, Italy
- Dipartimento di Fisica, Università di Roma 'Tor Vergata', Via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Robert Zielinski
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Milan Kubicki
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Maximilian Koy
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
| | - Canan Kosbab
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Simone Brozzesi
- Dipartimento di Fisica, Università di Roma 'Tor Vergata', Via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Ankita Das
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
| | - Mike Thomas Nehring
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Viktoria Balfanz
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Juls Brühne
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Mario Dähne
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Martin Franz
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
| | - Norbert Esser
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstrasse 36, D-10623, Berlin, Germany
- Leibniz-Institut für Analytische Wissenschaften - ISAS e.V., Schwarzschildstrasse 8, 12489, Berlin, Germany
| | - Frank Glorius
- Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany
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5
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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: 4] [Impact Index Per Article: 4.0] [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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6
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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: 5] [Impact Index Per Article: 5.0] [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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7
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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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8
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Wang S, Zhang C, Li D, Zhou Y, Su Z, Feng X, Dong S. New chiral N-heterocyclic olefin bifunctional organocatalysis in α-functionalization of β-ketoesters. Sci China Chem 2022. [DOI: 10.1007/s11426-022-1458-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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9
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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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10
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Ito S, Fujimoto H, Tobisu M. Non-Stabilized Vinyl Anion Equivalents from Styrenes by N-Heterocyclic Carbene Catalysis and Its Use in Catalytic Nucleophilic Aromatic Substitution. J Am Chem Soc 2022; 144:6714-6718. [PMID: 35404600 DOI: 10.1021/jacs.2c02579] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A protocol for the catalytic nucleophilic activation of unactivated styrenes is reported, which enables the generation of a non-stabilized alkenyl anion equivalent as a transient intermediate. In the reaction, N-heterocyclic carbenes add across styrenes to generate ylide intermediates, which can then be used in intramolecular nucleophilic aromatic substitution reactions of aryl fluorides, chlorides, and methyl ethers. The method allows for straightforward access to complex polyaromatic compounds.
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Affiliation(s)
- Sora Ito
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hayato Fujimoto
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Mamoru Tobisu
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Osaka 565-0871, Japan
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11
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Wu T, Tatton MR, Greaney MF. NHC Catalysis for Umpolung Pyridinium Alkylation via Deoxy-Breslow Intermediates. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 134:e202117524. [PMID: 38504766 PMCID: PMC10947523 DOI: 10.1002/ange.202117524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 11/09/2022]
Abstract
Umpolung N-heterocyclic carbene (NHC) catalysis of non-aldehyde substrates offers new pathways for C-C bond formation, but has proven challenging to develop in terms of viable substrate classes. Here, we demonstrate that pyridinium ions can undergo NHC addition and subsequent intramolecular C-C bond formation through a deoxy-Breslow intermediate. The alkylation demonstrates, for the first time, that deoxy-Breslow intermediates are viable for catalytic umpolung of areniums.
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Affiliation(s)
- Terence Wu
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Matthew R. Tatton
- Early Chemical DevelopmentPharmaceutical SciencesR&D, AstraZenecaMacclesfieldSK10 2NAUK
| | - Michael F. Greaney
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
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12
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Wu T, Tatton MR, Greaney MF. NHC Catalysis for Umpolung Pyridinium Alkylation via Deoxy-Breslow Intermediates. Angew Chem Int Ed Engl 2022; 61:e202117524. [PMID: 35103381 PMCID: PMC9306516 DOI: 10.1002/anie.202117524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 12/24/2022]
Abstract
Umpolung N-heterocyclic carbene (NHC) catalysis of non-aldehyde substrates offers new pathways for C-C bond formation, but has proven challenging to develop in terms of viable substrate classes. Here, we demonstrate that pyridinium ions can undergo NHC addition and subsequent intramolecular C-C bond formation through a deoxy-Breslow intermediate. The alkylation demonstrates, for the first time, that deoxy-Breslow intermediates are viable for catalytic umpolung of areniums.
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Affiliation(s)
- Terence Wu
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
| | - Matthew R. Tatton
- Early Chemical DevelopmentPharmaceutical SciencesR&D, AstraZenecaMacclesfieldSK10 2NAUK
| | - Michael F. Greaney
- School of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUK
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13
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Zhen G, Jiang K, Yin B. Progress in Organocatalytic Dearomatization Reactions Catalyzed by Heterocyclic Carbenes. ChemCatChem 2022. [DOI: 10.1002/cctc.202200099] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Guangjin Zhen
- South China University of Technology School of Chemistry and Chemical Engineering CHINA
| | - Kai Jiang
- South China University of Technology School of Chemistry and Chemical Engineering CHINA
| | - Biaolin Yin
- South China University of Technology Dept. of Chenistry and chemical engineering Wushan Street 510640 Guangzhou CHINA
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14
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Guthardt R, Mellin J, Bruhn C, Siemeling U. 1,1′‐Ferrocenylene‐Bridged Bis(N‐Heterocyclic Olefin) Derivatives. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100903] [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)
- Robin Guthardt
- Institut für Chemie Universität Kassel Heinrich-Plett-Straße 40 34132 Kassel Germany
| | - Johanna Mellin
- Institut für Chemie Universität Kassel Heinrich-Plett-Straße 40 34132 Kassel Germany
| | - Clemens Bruhn
- Institut für Chemie Universität Kassel Heinrich-Plett-Straße 40 34132 Kassel Germany
| | - Ulrich Siemeling
- Institut für Chemie Universität Kassel Heinrich-Plett-Straße 40 34132 Kassel Germany
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15
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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: 9] [Impact Index Per Article: 3.0] [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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16
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Shyam A, Pradhan AK, Mondal P. A density functional theory investigation on bis(diethylamino)cyclopropenylidene catalyzed synthesis of 1,4‐bifunctional compounds. J PHYS ORG CHEM 2021. [DOI: 10.1002/poc.4219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Abhijit Shyam
- Department of Chemistry Assam University Silchar India
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17
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Yasui K, Kamitani M, Fujimoto H, Tobisu M. N-Heterocyclic Carbene-Catalyzed Truce-Smiles Rearrangement of N-Arylacrylamides via the Cleavage of Unactivated C(aryl)-N Bonds. Org Lett 2021; 23:1572-1576. [PMID: 33577343 DOI: 10.1021/acs.orglett.0c04281] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report on the N-heterocyclic carbene (NHC)-catalyzed Truce-Smiles rearrangement of aniline derivatives, in which an unactivated C(aryl)-N bond is cleaved, leading to the formation of a new C(aryl)-C bond. The key to the success of this reaction is the utilization of a highly nucleophilic NHC, which enables the formation of a highly nucleophilic ylide intermediate that is generated from an α,β-unsaturated amide.
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Affiliation(s)
- Kosuke Yasui
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Miharu Kamitani
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Hayato Fujimoto
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Mamoru Tobisu
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
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18
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Li Z, Ji P, Cheng JP. Brönsted Basicities and Nucleophilicities of N-Heterocyclic Olefins in Solution: N-Heterocyclic Carbene versus N-Heterocyclic Olefin. Which Is More Basic, and Which Is More Nucleophilic? J Org Chem 2021; 86:2974-2985. [PMID: 33464082 DOI: 10.1021/acs.joc.0c02838] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A Brönsted basicity scale comprising nine representative N-heterocyclic olefins (NHOs) was established by measuring the equilibrium acidities of their corresponding precursors in DMSO using an ultraviolet-visible spectroscopic method. The basicities (pKaHs) of the investigated NHOs cover a range from 14.7 to 24.1. The basicities of unsaturated NHOs are stronger than those of their N-heterocyclic carbene (NHC) analogues; however, the basicities for the saturated ones are much weaker than those of their NHC analogues, which is largely due to the aromatization effect that intrinsically influences the acidic dissociations of NHC and NHO precursors. The nucleophilicities of four NHOs were measured photometrically by monitoring the kinetics of reactions of these NHOs with common reference electrophiles for quantifying nucleophilic reactivities. In general, the nucleophilicity of the NHOs is much stronger than that of commonly used Lewis bases such as Ph3P or DMAP [4-(dimethylamino)pyridine] but weaker than that of their NHC analogues; however, caution should be taken when generalizing this conclusion to a wide range of electrophiles with distinctively electronic and structural properties.
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Affiliation(s)
- Zhen Li
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Pengju Ji
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Jin-Pei Cheng
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China.,State Key Laboratory of Elemento-organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
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19
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Tan H, Wang S, Yan Z, Liu J, Wei J, Song S, Jiao N. N‐Heterocyclic Carbene Catalyzed Ester Synthesis from Organic Halides through Incorporation of Oxygen Atoms from Air. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202011039] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Hui Tan
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Shen‐An Wang
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Zixi Yan
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Jianzhong Liu
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Jialiang Wei
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Song Song
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Ning Jiao
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
- State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences Shanghai 200032 China
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20
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Tan H, Wang S, Yan Z, Liu J, Wei J, Song S, Jiao N. N‐Heterocyclic Carbene Catalyzed Ester Synthesis from Organic Halides through Incorporation of Oxygen Atoms from Air. Angew Chem Int Ed Engl 2020; 60:2140-2144. [DOI: 10.1002/anie.202011039] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/23/2020] [Indexed: 11/09/2022]
Affiliation(s)
- Hui Tan
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Shen‐An Wang
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Zixi Yan
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Jianzhong Liu
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Jialiang Wei
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Song Song
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Ning Jiao
- State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China
- State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences Shanghai 200032 China
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21
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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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22
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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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23
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Shyam A, Pradhan AK, Mondal P. Mechanistic Insights into the N‐Heterocyclic Carbene Catalyzed Synthesis of α,δ‐Diketones: A DFT Approach. ChemistrySelect 2020. [DOI: 10.1002/slct.202002811] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Abhijit Shyam
- Department of Chemistry Assam University Silchar 788011, Assam India
| | - Amit K. Pradhan
- Department of Chemistry Assam University Silchar 788011, Assam India
| | - Paritosh Mondal
- Department of Chemistry Assam University Silchar 788011, Assam India
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24
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Gulia N, Pigulski B, Szafert S. Base‐Promoted Double Amination of 1‐Haloalkynes: Direct Synthesis of Ene‐1,1‐diamines. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Nurbey Gulia
- Faculty of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
| | - Bartłomiej Pigulski
- Faculty of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
| | - Sławomir Szafert
- Faculty of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
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25
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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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26
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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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27
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von Seggern N, Schindler T, Naumann S. Dual Catalytic Ring-Opening Polymerization of Ethylene Carbonate for the Preparation of Degradable PEG. Biomacromolecules 2020; 21:2661-2669. [DOI: 10.1021/acs.biomac.0c00360] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Nils von Seggern
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Tamara Schindler
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Stefan Naumann
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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28
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Buzsáki D, Kelemen Z, Nyulászi L. Stretching the P-C Bond. Variations on Carbenes and Phosphanes. J Phys Chem A 2020; 124:2660-2671. [PMID: 32159965 PMCID: PMC7307921 DOI: 10.1021/acs.jpca.0c00641] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/10/2020] [Indexed: 11/28/2022]
Abstract
The stability and the structure of adducts formed between four substituted phosphanes (PX3, X:H, F, Cl, and NMe2) and 11 different carbenes have been investigated by DFT calculations. In most cases, the structure of the adducts depends strongly on the stability of the carbene itself, exhibiting a linear correlation with the increasing dissociation energy of the adduct. Carbenes of low stability form phosphorus ylides (F), which can be described as phosphane → carbene adducts supported with some back-bonding. The most stable carbenes, which have high energy lone pair, do not form stable F-type structures but carbene → phosphane adducts (E-type structure), utilizing the low-lying lowest unoccupied molecular orbital (LUMO) of the phosphane (with electronegative substituents), benefiting also from the carbene-pnictogen interaction. Especially noteworthy is the case of PCl3, which has an extremely low energy LUMO in its T-shaped form. Although this PCl3 structure is a transition state of rather high energy, the large stabilization energy of the complex makes this carbene-phosphane adduct stable. Most interestingly, in case of carbenes with medium stability both F- and E-type structures could be optimized, giving rise to bond-stretch isomerism. Likewise, for phosphorus ylides (F), the stability of the adducts G formed from carbenes with hypovalent phosphorus (PX-phosphinidene) is in a linear relationship with the stabilization of the carbene. Adducts of carbenes with hypervalent phosphorus (PX5) are the most stable when X is electronegative, and the carbene is highly nucleophilic.
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Affiliation(s)
- Dániel Buzsáki
- Department
of Inorganic and Analytical Chemistry, Budapest
University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary
| | - Zsolt Kelemen
- Department
of Inorganic and Analytical Chemistry, Budapest
University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary
| | - László Nyulászi
- Department
of Inorganic and Analytical Chemistry, Budapest
University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary
- MTA-BME
Computation Driven Chemistry Research Group, Szent Gellért tér 4, H-1111 Budapest, Hungary
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29
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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: 47] [Impact Index Per Article: 11.8] [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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30
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Konstandaras N, Dunn MH, Luis ET, Cole ML, Harper JB. The pK a values of N-aryl imidazolinium salts, their higher homologues, and formamidinium salts in dimethyl sulfoxide. Org Biomol Chem 2020; 18:1910-1917. [PMID: 32095802 DOI: 10.1039/d0ob00036a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A series of imidazolinium salts, their six-, seven- and eight-membered homologues, and the related formamidinium salts were prepared, and their pKa values were determined in DMSO at 25 °C using the bracketing indicator method. The effect of each type of structural variation on the acidity of each salt was considered, particularly noting the importance of ring size and the effect of the steric and electronic nature of the N-aryl substituents. The effect of a cyclic structure was also probed through comparing the cyclic systems with the corresponding formamidinium salts, noting the importance of conformational flexibility in the latter cases. Along with allowing choice of appropriate bases for deprotonation of these species, it is anticipated that the data presented will aid in the understanding of the nucleophilicity, and potentially catalytic efficacy, of the corresponding carbenes.
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Affiliation(s)
- Nicholas Konstandaras
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Michelle H Dunn
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Ena T Luis
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Marcus L Cole
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
| | - Jason B Harper
- School of Chemistry, University of New South Wales, UNSW Sydney, NSW 2052, Australia.
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31
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Shyam A, Mondal P. Theoretical Insight towards Mechanism, Role of NHC and DBU in the Synthesis of Substituted Quinolines. ChemistrySelect 2020. [DOI: 10.1002/slct.201903697] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Abhijit Shyam
- Department of ChemistryAssam University, Silchar, Silchar Assam 788011 India
| | - Paritosh Mondal
- Department of ChemistryAssam University, Silchar, Silchar Assam 788011 India
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32
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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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33
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Satyam K, Harish B, Nanubolu JB, Suresh S. N-Heterocyclic carbene (NHC)-catalyzed tandem imine umpolung–aza-Michael addition–oxidation of β-carboline cyclic imines. Chem Commun (Camb) 2020; 56:2803-2806. [DOI: 10.1039/d0cc00321b] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N-Heterocyclic carbene (NHC)-catalyzed tandem imine umpolung–aza-Michael addition–oxidation of cyclic imines for the synthesis of a wide range of biologically relevant β-carboline-1-one derivatives has been disclosed.
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Affiliation(s)
- Killari Satyam
- Department of Organic Synthesis and Process Chemistry
- CSIR-Indian Institute of Chemical Technology (CSIR-IICT)
- Hyderabad 500 007
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Battu Harish
- Department of Organic Synthesis and Process Chemistry
- CSIR-Indian Institute of Chemical Technology (CSIR-IICT)
- Hyderabad 500 007
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Jagadeesh Babu Nanubolu
- Laboratory of X-Ray Crystallography
- Department of Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology (CSIR-IICT)
- Hyderabad 500 007
- India
| | - Surisetti Suresh
- Department of Organic Synthesis and Process Chemistry
- CSIR-Indian Institute of Chemical Technology (CSIR-IICT)
- Hyderabad 500 007
- India
- Academy of Scientific and Innovative Research (AcSIR)
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34
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Naumann S. Synthesis, properties & applications of N-heterocyclic olefins in catalysis. Chem Commun (Camb) 2019; 55:11658-11670. [PMID: 31517349 DOI: 10.1039/c9cc06316a] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N-Heterocyclic olefins (NHOs), a recently (re-)discovered type of electron-rich, polar alkene, are comprehensively presented. Along with synthetic aspects and chemical properties, special emphasis is put on the multi-faceted impact NHOs already have had on catalysis. This is discussed along the lines of small molecule organocatalysis, organo- and metal-assisted polymerization and of the understanding and application of NHO-ligated organometallic complexes. Highlighted are the strong basicity of NHOs ("superbases"), their high nucleophilicity and the design principles to tailor NHO (organo-)catalysts. It is demonstrated that NHOs can complement, and in many cases out-perform, the much better established N-heterocyclic carbene-based systems. Examples include among others CO2-sequestration, the polymerization of lactones and epoxides or the transfer hydrogenation of carbonyls. Further, the unique ability to selectively address basic or nucleophilic reaction pathways via NHO-mediation is detailed, as is the bonding situation in NHO-metal complexes and the ability of the olefin to act as an electronically flexible ligand.
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Affiliation(s)
- Stefan Naumann
- University of Stuttgart, Institute of Polymer Chemistry, 70569 Stuttgart, Germany.
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35
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Nguyen XB, Nakano Y, Duggan NM, Scott L, Breugst M, Lupton DW. N‐Heterocyclic Carbene Catalyzed (5+1) Annulations Exploiting a Vinyl Dianion Synthon Strategy. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201905475] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xuan B. Nguyen
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Yuji Nakano
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | | | - Lydia Scott
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Martin Breugst
- Department für Chemie Universität zu Köln Greinstraße 4 50939 Köln Germany
| | - David W. Lupton
- School of Chemistry Monash University Clayton 3800 Victoria Australia
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36
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Zhang X, Wang L, Wang Q, Ge F, Wang X. Synthesis, Characterization of Pyridyl Heterocyclic Olefins (PHOs) and Activation of Heterocumulenes. ChemistrySelect 2019. [DOI: 10.1002/slct.201902563] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Xianhui Zhang
- Key Laboratory of Biobased MaterialsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences 189 Songling Road Qingdao 266101 China
- Center of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of Sciences Beijing 10049 China
| | - Liang Wang
- Key Laboratory of Biobased MaterialsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences 189 Songling Road Qingdao 266101 China
| | - Qinggang Wang
- Key Laboratory of Biobased MaterialsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences 189 Songling Road Qingdao 266101 China
| | - Fang Ge
- College of Chemistry and Chemical EngineeringQingdao University Shandong 266071 China
| | - Xiaowu Wang
- Key Laboratory of Biobased MaterialsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences 189 Songling Road Qingdao 266101 China
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37
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Nguyen XB, Nakano Y, Duggan NM, Scott L, Breugst M, Lupton DW. N‐Heterocyclic Carbene Catalyzed (5+1) Annulations Exploiting a Vinyl Dianion Synthon Strategy. Angew Chem Int Ed Engl 2019; 58:11483-11490. [DOI: 10.1002/anie.201905475] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Xuan B. Nguyen
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Yuji Nakano
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | | | - Lydia Scott
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Martin Breugst
- Department für Chemie Universität zu Köln Greinstraße 4 50939 Köln Germany
| | - David W. Lupton
- School of Chemistry Monash University Clayton 3800 Victoria Australia
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38
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Walther P, Krauß A, Naumann S. Lewis Pair Polymerization of Epoxides via Zwitterionic Species as a Route to High-Molar-Mass Polyethers. Angew Chem Int Ed Engl 2019; 58:10737-10741. [PMID: 31099454 DOI: 10.1002/anie.201904806] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Indexed: 11/08/2022]
Abstract
A dual catalytic setup based on N-heterocyclic olefins (NHOs) and magnesium bis(hexamethyldisilazide) (Mg(HMDS)2 ) was used to prepare poly(propylene oxide) with a molar mass (Mn ) >500 000 g mol-1 , in some cases even >106 g mol-1 , as determined by GPC/light scattering. This is achieved by combining the rapid polymerization characteristics of a zwitterionic, Lewis pair type mechanism with the efficient epoxide activation by the MgII species. Transfer-to-monomer, traditionally frustrating attempts at synthesizing polyethers with a high degree of polymerization, is practically removed as a limiting factor by this approach. NMR and MALDI-ToF MS experiments reveal key aspects of the proposed mechanism, whereby the polymerization is initiated via nucleophilic attack by the NHO on the activated monomer, generating a zwitterionic species. This strategy can also be extended to other epoxides, including functionalized monomers.
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Affiliation(s)
- Patrick Walther
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Annabelle Krauß
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Stefan Naumann
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
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39
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Walther P, Krauß A, Naumann S. Darstellung von hochmolekularen Polyethern durch die zwitterionische Lewis‐Paar‐Polymerisation von Epoxiden. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201904806] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Patrick Walther
- Institut für PolymerchemieUniversität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Annabelle Krauß
- Institut für PolymerchemieUniversität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Stefan Naumann
- Institut für PolymerchemieUniversität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
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40
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Transition-metal-free insertion of benzyl bromides into 2-(1H-benzo[d]imidazol-1-yl)benzaldehyde: One-pot switchable syntheses of benzo[4,5]imidazo[1,2-a]quinolin-5(7H)-ones and 3-arylquinolin-4-ones mediated by base. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.03.058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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41
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Singh T, George A, Parameswaran P, Bharatam PV. Enols, Diamino Enols, and Breslow Intermediates: A Comparative Quantum Chemical Analysis. European J Org Chem 2019. [DOI: 10.1002/ejoc.201801817] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tejender Singh
- Department of Medicinal Chemistry; National Institute of Pharmaceutical Education and Research (NIPER), Sector 67; 160 062 S.A.S. Nagar - Punjab India
| | - Anjana George
- Department of Chemistry; National Institute of Technology Calicut; NIT Calicut Campus P.O. 673 601 Kozhikode - Kerala India
| | - Pattiyil Parameswaran
- Department of Chemistry; National Institute of Technology Calicut; NIT Calicut Campus P.O. 673 601 Kozhikode - Kerala India
| | - Prasad V. Bharatam
- Department of Medicinal Chemistry; National Institute of Pharmaceutical Education and Research (NIPER), Sector 67; 160 062 S.A.S. Nagar - Punjab India
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42
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Schuldt R, Kästner J, Naumann S. Proton Affinities of N-Heterocyclic Olefins and Their Implications for Organocatalyst Design. J Org Chem 2019; 84:2209-2218. [DOI: 10.1021/acs.joc.8b03202] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Robin Schuldt
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Johannes Kästner
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Stefan Naumann
- Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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43
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Patra A, James A, Das TK, Biju AT. Oxidative NHC Catalysis for the Generation of Imidoyl Azoliums: Synthesis of Benzoxazoles. J Org Chem 2018; 83:14820-14826. [DOI: 10.1021/acs.joc.8b02598] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Atanu Patra
- Organic Chemistry Division, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune 411008, India
| | - Anjima James
- Organic Chemistry Division, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune 411008, India
| | - Tamal Kanti Das
- Organic Chemistry Division, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune 411008, India
| | - Akkattu T. Biju
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
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44
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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: 175] [Impact Index Per Article: 29.2] [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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45
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Scott L, Nakano Y, Zhang C, Lupton DW. Enantioselective N‐Heterocyclic Carbene Catalyzed Cyclopentene Synthesis via the β‐Azolium Ylide. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804271] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Lydia Scott
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Yuji Nakano
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Changhe Zhang
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - David W. Lupton
- School of Chemistry Monash University Clayton 3800 Victoria Australia
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46
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Scott L, Nakano Y, Zhang C, Lupton DW. Enantioselective N‐Heterocyclic Carbene Catalyzed Cyclopentene Synthesis via the β‐Azolium Ylide. Angew Chem Int Ed Engl 2018; 57:10299-10303. [DOI: 10.1002/anie.201804271] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 05/30/2018] [Indexed: 01/04/2023]
Affiliation(s)
- Lydia Scott
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Yuji Nakano
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - Changhe Zhang
- School of Chemistry Monash University Clayton 3800 Victoria Australia
| | - David W. Lupton
- School of Chemistry Monash University Clayton 3800 Victoria Australia
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47
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Wang Q, Zhao W, Zhang S, He J, Zhang Y, Chen EYX. Living Polymerization of Conjugated Polar Alkenes Catalyzed by N-Heterocyclic Olefin-Based Frustrated Lewis Pairs. ACS Catal 2018. [DOI: 10.1021/acscatal.8b00333] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Qianyi Wang
- State Key Laboratory
of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, China
| | - Wuchao Zhao
- State Key Laboratory
of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, China
| | - Sutao Zhang
- State Key Laboratory
of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, China
| | - Jianghua He
- State Key Laboratory
of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, China
| | - Yuetao Zhang
- State Key Laboratory
of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, China
| | - Eugene Y.-X. Chen
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
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48
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Patra A, Gelat F, Pannecoucke X, Poisson T, Besset T, Biju AT. Synthesis of 4-Difluoromethylquinolines by NHC-Catalyzed Umpolung of Imines. Org Lett 2018; 20:1086-1089. [DOI: 10.1021/acs.orglett.7b04055] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Atanu Patra
- Organic
Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi
Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110020, India
| | - Fabien Gelat
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | - Xavier Pannecoucke
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | - Thomas Poisson
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
- Institut Universitaire de France, 103 boulevard Saint-Michel, 75005 Paris, France
| | - Tatiana Besset
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | - Akkattu T. Biju
- Organic
Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi
Bhabha Road, Pune 411008, India
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49
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Li W, Huang D, Lyu Y. A comparative computational study of N-heterocyclic olefin and N-heterocyclic carbene mediated carboxylative cyclization of propargyl alcohols with CO 2. Org Biomol Chem 2018; 14:10875-10885. [PMID: 27812589 DOI: 10.1039/c6ob01901c] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The carboxylative cyclization of a propargyl alcohol with CO2 mediated by a N-heterocyclic olefin (NHO) or N-heterocyclic carbene (NHC) has been comparatively studied using density functional theory (DFT) calculations. The calculations show that the advantageous catalytic performance of the NHO in the title reaction can be attributed to two aspects: (i) the active site of the NHO extends outside the imidazolium ring, which enhances the reactivity and stability of the [NHOH]+[carbonate]- ionic pair intermediate. Thus, the turnover frequency (TOF)-determining intramolecular cyclization step is kinetically more favorable in the NHO system. (ii) As the basicity of the NHO is weaker than the NHC, deprotonation of the propargyl alcohol by the NHO is relatively more difficult. Consequently, the side reaction of ring-opening transesterification of the α-alkylidene cyclic carbonate with the nucleophilic [NHOH]+[alkoxide]- ionic pair intermediate can be inhibited using the NHO system. The present mechanistic study provides a basis for further application of these promising organocatalysts in more organic transformations.
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Affiliation(s)
- Weiyi Li
- School of Science, Xihua University, Chengdu, 610039, Sichuan, P. R. China.
| | - Dongfeng Huang
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan 455000, P. R. China
| | - Yajing Lyu
- School of Science, Xihua University, Chengdu, 610039, Sichuan, P. R. China.
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50
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Feroci M, Chiarotto I, Orsini M, Pandolfi F, Zane D, Inesi A. Electrogenerated N-Heterocyclic Olefins: Stability and Catalytic Ability. ChemElectroChem 2017. [DOI: 10.1002/celc.201700992] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marta Feroci
- Dept. Fundamental and Applied Sciences for Engineering (SBAI); Sapienza University of Rome; via Castro Laurenziano, 7 00161 Rome Italy
| | - Isabella Chiarotto
- Dept. Fundamental and Applied Sciences for Engineering (SBAI); Sapienza University of Rome; via Castro Laurenziano, 7 00161 Rome Italy
| | - Monica Orsini
- Dept. of Engineering; Università RomaTre; via V. Volterra, 62 00146 Rome Italy
| | - Fabiana Pandolfi
- Dept. Fundamental and Applied Sciences for Engineering (SBAI); Sapienza University of Rome; via Castro Laurenziano, 7 00161 Rome Italy
| | - Daniela Zane
- CNR SMN Istituto per lo Studio dei Materiali Nanostrutturati UOS Sapienza; Via del Castro Laurenziano 7 00161 Roma Italy
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