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Zafar M, Subramaniyan V, Tibika F, Tulchinsky Y. Cationic ligands - from monodentate to pincer systems. Chem Commun (Camb) 2024; 60:9871-9906. [PMID: 38920056 DOI: 10.1039/d4cc01489h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2024]
Abstract
For a long time, the small group of cationic ligands stood out as obscure systems within the general landscape of coordinative chemistry. However, this situation has started to change rapidly during the last decade, with more and more examples of metal-coordinated cationic species being reported. The growing interest in these systems is not only of purely academic nature, but also driven by accumulating evidence of their high catalytic utility. Overcoming the inherently poor coordinating ability of cationic species often required additional structural stabilization. In numerous cases this was realized by functionalizing them with a pair of chelating side-arms, effectively constructing a pincer-type scaffold. This comprehensive review aims to encompass all cationic ligands possessing such pincer architecture reported to date. Herein every cationic species that has ever been embedded in a pincer framework is described in terms of its electronic structure, followed by an in-depth discussion of its donor/acceptor properties, based on computational studies (DFT) and available experimental data (IR, NMR or CV). We then elaborate on how the positive charge of these ligands affects the spectroscopic and redox properties, as well as the reactivity, of their complexes, compared to those of the structurally related neutral ligands. Among other systems discussed, this review also surveys our own contribution to this field, namely, the introduction of sulfonium-based pincer ligands and their complexes, recently reported by our group.
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Affiliation(s)
- Mohammad Zafar
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
| | | | - Françoise Tibika
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
| | - Yuri Tulchinsky
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
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2
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Siwatch RK, Yang MC, Su MD, So CW. A Digermanium(III) 1,2-Dication Stabilized by Amidinate and cAAC-Phosphinidenide Ligands. Inorg Chem 2024; 63:8511-8515. [PMID: 38687917 DOI: 10.1021/acs.inorgchem.4c00471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
A digermanium(III) 1,2-dication comprises two cationic centers located at two interconnected Ge atoms. The strong Coulombic repulsion between two positively charged germanium cations hinders their bond formation. Balancing these two oppositions was achieved by using amidinate and cyclic (alkyl)amino carbene (cAAC)-phosphinidenide ligands, where an amidinato cAAC-phosphinidenidogermylene complex, [LGeP(cAACMe)] (2, where L = PhC(NtBu)2, cAACMe = :C{C(Me)2CH2C(Me)2NAr}, and Ar = 2,6-iPr2C6H3), underwent one-electron oxidation with a bis(phosphinidene) radical cation, [(cAACMe)P]2•+, to form a digermanium(III) 1,2-dication, [LGeP(cAACMe)]22+, in compound 4.
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Affiliation(s)
- Rahul Kumar Siwatch
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371 Singapore
| | - Ming-Chung Yang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Cheuk-Wai So
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371 Singapore
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3
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Rana SS, Choudhury J. Unveiling N-Fused Nitreniums as Potent Catalytic Photooxidants. J Am Chem Soc 2024; 146:3603-3608. [PMID: 38293737 DOI: 10.1021/jacs.3c12606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
The first example of a hitherto-unknown facet of catalytic photooxidant capability of nitrenium cations is reported herein. The fundamental limitation of inability of the traditional and reported nitreniums to achieve the excited-state redox potential beyond +2.0 V (vs Ag/AgCl), the primary requirement for a powerful photooxidant, is addressed in this work by developing a structurally unique class of N-fused nitrenium cations, with the required structural engineering involving extensive π-conjugation through ring fusion at the nitrenium site, which enabled significant lowering of the LUMO energy and easy reduction at the excited state (excited-state redox potential up to +2.5 V vs Ag/AgCl), facilitated by effective delocalization/stabilization of the generated radical. This finding opens a new way to discover novel and useful (photo)catalytic properties of nitrenium cations beyond just Lewis acidity.
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Affiliation(s)
- Samim Sohel Rana
- Organometallics & Smart Materials Laboratory, Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462 066, India
| | - Joyanta Choudhury
- Organometallics & Smart Materials Laboratory, Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462 066, India
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4
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Li R, Zafar M, Danovich D, Subramaniyan V, Tibika F, Tulchinsky Y. Sulfonium Cation in the Service of π-Acid Catalysis. Angew Chem Int Ed Engl 2024; 63:e202314997. [PMID: 38009835 DOI: 10.1002/anie.202314997] [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: 10/06/2023] [Revised: 11/17/2023] [Accepted: 11/27/2023] [Indexed: 11/29/2023]
Abstract
While still rare, cationic ligands offer much promise as tunable electron-withdrawing ligands for π-acid catalysis. Recently, we introduced pincer-type sulfonium cations into the list of available strongly π-acidic ancillary ligands. However, the M-S bond in sulfonium complexes of these ligands was found highly labile, precluding their catalytic applications. Herein we demonstrate that this obstacle can be overcome by increasing the rigidity of the sulfonium pincer scaffold. X-ray analyses confirm that despite bearing a formal positive charge, the sulfur atom of this newly designed sulfonium ligand maintains its coordination to the Pt(II)-center, while DFT calculations indicate that by doing so it strongly enhances the electrophilic character of the metal. Kinetic studies carried out on three model cycloisomerization reactions prove that such a tris-cationic sulfonium-Pt(II) complex is highly reactive, compared to its thioether-based analogue. This proof-of-concept study presents the first example of employing sulfonium-based ligands in homogeneous catalysis.
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Affiliation(s)
- Ruiping Li
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Mohammad Zafar
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - David Danovich
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | | | - Françoise Tibika
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Yuri Tulchinsky
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
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5
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Avigdori I, Singh K, Fridman N, Gandelman M. Nitrenium ions as new versatile reagents for electrophilic amination. Chem Sci 2023; 14:12034-12040. [PMID: 37969608 PMCID: PMC10631241 DOI: 10.1039/d3sc04268e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 09/25/2023] [Indexed: 11/17/2023] Open
Abstract
Herein we report the utilization of N-heterocyclic nitrenium ions - easily prepared, bench-stable and non-oxidating nitrogen sources for the efficient electrophilic amination of aliphatic and aromatic organometallic nucleophiles, towards the facile and general preparation of primary amines. To this end, a plethora of abundant organolithium and organomagnesium reagents were combined with nitrenium salts to generate a variety of previously unexplored N-alkyl and N-aryl triazanes. Through the simple hydrogenolysis of these relatively stable triazanes, we have prepared a diverse scope of primary amines, including linear and branched aliphatic as well as (hetero)aromatic amines possessing various stereo-electronic substituents. Furthermore, we present the facile synthesis of valuable 15N-labelled primary amines from easily prepared 15N-labelled nitrenium salts, as well as a one-pot approach to biologically relevant primary amines. Finally, a recyclable variant of the nitrenium precursor was prepared and a simple recovery protocol was developed to improve the atom-economy of this procedure.
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Affiliation(s)
- Idan Avigdori
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Kuldeep Singh
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Technion City Haifa 32000 Israel
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6
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Ren XJ, Liao PW, Sheng H, Wang ZX, Chen XY. N-Heterocyclic Nitrenium-Catalyzed Photohomolysis of CF 3SO 2Cl for Alkene Trifluoromethylation. Org Lett 2023; 25:6189-6194. [PMID: 37578296 DOI: 10.1021/acs.orglett.3c02380] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
N-Heterocyclic nitreniums (NHNs) have been utilized as Lewis acid catalysts to activate substrates with lone pairs. Alternative to their conventional applications, we have discovered that NHNs can also serve as charge transfer complex catalysts. Herein, we present another potential of NHNs by utilizing a weak interaction between NHNs and CF3SO2Cl. The method promotes CF3SO2Cl to undergo photohomolysis, resulting in the CF3 radical. Mechanistic studies suggested that the weak interaction could be due to the π-hole effect of NHNs.
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Affiliation(s)
- Xiao-Jian Ren
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng-Wei Liao
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - He Sheng
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi-Xiang Wang
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou, Shandong Province 256606, China
| | - Xiang-Yu Chen
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou, Shandong Province 256606, China
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7
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Li R, Barel N, Subramaniyan V, Tibika F, Hoffman R, Tulchinsky Y. Sulfonium-Pincer Ligands Flexibility in Pt(II) Complexes. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Ruiping Li
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Nitsan Barel
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | | | - Françoise Tibika
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Roy Hoffman
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
| | - Yuri Tulchinsky
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
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8
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Koronatov A, Mauda A, Tumansky B, Kaushansky A, Fridman N, Bravo-Zhivotovskii D, Gandelman M. Multimodal Reactivity of N-H Bonds in Triazanes and Isolation of a Triazinyl Radical. J Am Chem Soc 2022; 144:23642-23648. [PMID: 36525645 DOI: 10.1021/jacs.2c11113] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The employment of nitrogen Lewis acids based on nitrenium cations has been increasingly featured in the fields of main group chemistry and catalysis. A formally reduced form of nitrenium D─cyclic triazanes E─are intriguing chemical compounds, the chemistry of which is completely unexplored. In this work, we reveal that N-H-triazanes exhibit unusual N-H bond properties; namely, they can serve as protons, hydrides, or hydrogen atom donors. This unique multimodal reactivity provides an N-cation, N-anion, or N-radical from the same species. It allowed us to isolate, for the first time, a stable naphto[1,2,3]triazinyl radical, which was fully characterized both computationally and experimentally, including its monomeric X-ray structure. Moreover, this radical can be prepared directly from the nitrenium cation by a single electron reduction (E = -0.46 V), and this process is reversible. We envision versatile uses of this radical in synthetic and materials chemistry.
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Affiliation(s)
- Aleksandr Koronatov
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Assaf Mauda
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Boris Tumansky
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Alexander Kaushansky
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Dmitry Bravo-Zhivotovskii
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion─Israel Institute of Technology, Technion City, Haifa 32000, Israel
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9
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Chen KQ, Zhang BB, Wang ZX, Chen XY. N-Heterocyclic Nitreniums Can Be Employed as Photoredox Catalysts for the Single-Electron Reduction of Aryl Halides. Org Lett 2022; 24:4598-4602. [PMID: 35709368 DOI: 10.1021/acs.orglett.2c01702] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
N-Heterocyclic nitrenium (NHN) salts, the analogues of N-heterocyclic carbenes, have attracted considerable interest. However, relatively little is known about their catalytic ability beyond their Lewis acid catalysis. Herein, we describe that NHNs can serve as catalytic electron acceptors for charge transfer complex photoactivations. We showcase that, under blue light irradiation, the NHN salts could catalyze the generation of aryl radicals from aryl halides.
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Affiliation(s)
- Kun-Quan Chen
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bei-Bei Zhang
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi-Xiang Wang
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiang-Yu Chen
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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10
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Ranolia D, Avigdori I, Singh K, Koronatov A, Fridman N, Gandelman M. Triazolium Salts as Lewis Acid Catalysts. Org Lett 2022; 24:3915-3919. [PMID: 35617625 DOI: 10.1021/acs.orglett.2c01108] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We describe a new type of nitrenium-based Lewis acids: tetraaryl-1,2,3-triazolium salts. These were fully characterized by NMR and X-ray crystallography. The Gutmann-Beckett acidity numbers were determined to be up to 35.6, which is high compared to those of previously studied nitrenium salts. These salts catalyze the facile hydrosilylation-deoxygenation of ketones, aldehydes, acetals, alcohols, ethers, and silyl ethers under mild conditions in excellent yields. To our knowledge, this represents a first example of triazolium ions used as Lewis acid catalysts.
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Affiliation(s)
- Deepak Ranolia
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Idan Avigdori
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Kuldeep Singh
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Aleksandr Koronatov
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
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11
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Singh K, Avigdori I, Kaushansky A, Fridman N, Toledano D, Gandelman M. New Generation of Nitrenium Salts: Catalytic Hydrosilylation of Imines and a Mechanism of Action of Nitrogen Lewis Acids. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01297] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Kuldeep Singh
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Idan Avigdori
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Alexander Kaushansky
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Dor Toledano
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel
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12
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Li R, Barel N, Subramaniyan V, Cohen O, Tibika F, Tulchinsky Y. Sulfonium cations as versatile strongly π-acidic ligands. Chem Sci 2022; 13:4770-4778. [PMID: 35655889 PMCID: PMC9067576 DOI: 10.1039/d2sc00588c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 03/14/2022] [Indexed: 01/31/2023] Open
Abstract
More than a century old, sulfonium cations are still intriguing species in the landscape of organic chemistry. On one hand they have found broad applications in organic synthesis and materials science, but on the other hand, while isoelectronic to the ubiquitous tertiary phosphine ligands, their own coordination chemistry has been neglected for the last three decades. Here we report the synthesis and full characterization of the first Rh(i) and Pt(ii) complexes of sulfonium. Moreover, for the first time, coordination of an aromatic sulfonium has been established. A thorough computational analysis of the exceptionally short S-Rh bonds obtained attests to the strongly π-accepting nature of sulfonium cations and places them among the best π-acceptor ligands available today. Our calculations also show that embedding within a pincer framework enhances their π-acidity even further. Therefore, in addition to the stability and modularity that these frameworks offer, our pincer complexes might open the way for sulfonium cations to become powerful tools in π-acid catalysis.
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Affiliation(s)
- Ruiping Li
- Institute of Chemistry, The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | - Nitsan Barel
- Institute of Chemistry, The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | | | - Orit Cohen
- Institute of Chemistry, The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | - Françoise Tibika
- Institute of Chemistry, The Hebrew University of Jerusalem Jerusalem 9190401 Israel
| | - Yuri Tulchinsky
- Institute of Chemistry, The Hebrew University of Jerusalem Jerusalem 9190401 Israel
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13
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Maser L, Vogt M, Langer R. Cationic ligands between σ-donation and hydrogen-bridge-bond-stabilisation of ancillary ligands in coinage metal complexes with protonated carbodiphosphoranes. Dalton Trans 2022; 51:17397-17404. [DOI: 10.1039/d2dt02338e] [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
Protonated carbodiphosphoranes are demonstrated to act as σ- or hydrogen-bridge-bond donors in a series of copper and silver complexes.
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Affiliation(s)
- Leon Maser
- Institute of Chemistry, Faculty of Natural Sciences II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle (Saale), Germany
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35043 Marburg, Germany
| | - Matthias Vogt
- Institute of Chemistry, Faculty of Natural Sciences II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle (Saale), Germany
| | - Robert Langer
- Institute of Chemistry, Faculty of Natural Sciences II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle (Saale), Germany
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35043 Marburg, Germany
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14
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Zhang ZF, Su MD. Theoretical investigations in the reactions of group 15 analogues of the monocationic five-membered N-heterocyclic carbenes: interplay of electrophilicity, basicity, and aromaticity governing the reactivity. NEW J CHEM 2022. [DOI: 10.1039/d1nj04631d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The nature of the group 15 analogs of the five-membered N-heterocyclic carbenes (G15-Rea; G15 = N, P, As, Sb, and Bi) was investigated by using various methodologies.
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Affiliation(s)
- Zheng-Feng Zhang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
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15
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Wang W, Zheng X, Zhang L, Li S, Zhao Y, Wang X. Cyclic (Amino)(Aryl)Nitrenium Cations with Lewis Acidity Controlled by Remote Substituents. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202100690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Wenqing Wang
- College of Chemistry and Material Science, Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule‐Based Materials Anhui Normal University Wuhu Anhui 241002 China
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210023 China
| | - Xin Zheng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210023 China
- College of Science Henan Agricultural University Zhengzhou Henan 450002 China
| | - Leran Zhang
- College of Chemistry and Material Science, Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule‐Based Materials Anhui Normal University Wuhu Anhui 241002 China
| | - Shunjie Li
- College of Chemistry and Material Science, Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule‐Based Materials Anhui Normal University Wuhu Anhui 241002 China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210023 China
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210023 China
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16
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Zhu D, Qu Z, Zhou J, Stephan DW. The Reactivity of Isomeric Nitrenium Lewis Acids with Phosphines, Carbenes, and Phosphide. Chemistry 2021; 27:2861-2867. [PMID: 33137240 PMCID: PMC7898612 DOI: 10.1002/chem.202004798] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Indexed: 11/25/2022]
Abstract
Alkylation of spiro[fluorene-9,3'-indazole] at N(1) and N(2) with tBuCl affords the nitrenium cations [C6 H4 N2 (tBu)C(C12 H8 )][BF4 ], 1 and 2, respectively. Compound 1 converts to 2 over the temperature range 303-323 K with a free energy barrier of 28±5 kcal mol-1 . Reaction of 1 with PMe3 afforded the N-bound phosphine adduct [C6 H4 N(tBu)N(PMe3 )C(C12 H8 )]BF4 ] 3. However, phosphines attack 2 at the para-carbon atom of the aryl group with concurrent cleavage of N(2)-C(1) bond and proton migration to C(1) affording [(R3 P)C6 H3 NN(tBu)CH(C12 H8 )][BF4 ] (R=Me 4, nBu 5). Analogous reactions of 1 and 2 with the carbene SIMes prompt attack at the para-carbon with concurrent loss of H. affording the radical cation salts [(SIMes)C6 H3 N(tBu)NC(C12 H8 ). ][BF4 ] 6 and [(SIMes)C6 H3 NN(tBu)C(C12 H8 ). ][BF4 ] 7, whereas reaction of 2 with BAC gives the Lewis acid-base adduct, [C6 H4 N(BAC)N(tBu)C(C12 H8 )][BF4 ] 8. Finally, reactions of 1 and 2 with KPPh2 result in electron transfer affording (PPh2 )2 and the persistent radicals C6 H4 N(tBu)NC(C12 H8 ). and C6 H4 NN(tBu)C(C12 H8 ). . The detailed reaction mechanisms are also explored by extensive DFT calculations.
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Affiliation(s)
- Diya Zhu
- Department of ChemistryUniversity of Toronto80 St George StTorontoOntarioM5S3H6Canada
| | - Zheng‐Wang Qu
- Mulliken Center for Theoretical ChemistryInstitut für Physikalische und Theoretische ChemieRheinische Friedrich-Wilhelms-Universität BonnBeringstrasse 453115BonnGermany
| | - Jiliang Zhou
- Department of ChemistryUniversity of Toronto80 St George StTorontoOntarioM5S3H6Canada
| | - Douglas W. Stephan
- Department of ChemistryUniversity of Toronto80 St George StTorontoOntarioM5S3H6Canada
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17
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Sun X, Zhu C. Synthesis, characterization and reactivity of a neutral antimony(III) complex. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2020.07.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Avigdori I, Pogoreltsev A, Kaushanski A, Fridman N, Gandelman M. Frustrated Lewis Pairs Comprising Nitrogen Lewis Acids for Si–H Bond Activation. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008798] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Idan Avigdori
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Alla Pogoreltsev
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Alexander Kaushanski
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
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Avigdori I, Pogoreltsev A, Kaushanski A, Fridman N, Gandelman M. Frustrated Lewis Pairs Comprising Nitrogen Lewis Acids for Si–H Bond Activation. Angew Chem Int Ed Engl 2020; 59:23476-23479. [DOI: 10.1002/anie.202008798] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/05/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Idan Avigdori
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Alla Pogoreltsev
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Alexander Kaushanski
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry Technion—Israel Institute of Technology Technion City Haifa 32000 Israel
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20
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Hassin A, Fridman N, Gandelman M. Bidentate Triazolate-Based Ligand System: Synthesis, Coordination Modes, and Cooperative Bond Activation. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00775] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Asaf Hassin
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
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Radhakrishna L, Kunchur HS, Namdeo PK, Butcher RJ, Balakrishna MS. New 1,2,3-triazole based bis- and trisphosphine ligands: synthesis, transition metal chemistry and catalytic studies. Dalton Trans 2020; 49:3434-3449. [DOI: 10.1039/c9dt04302k] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This paper describes a novel synthetic methodology for the preparation of 1,2,3-triazole based phosphines and their transition metal chemistry and preliminary catalytic studies.
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Affiliation(s)
| | - Harish S. Kunchur
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Powai
- India
| | - Pavan K. Namdeo
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Powai
- India
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22
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Levy Vahav H, Pogoreltsev A, Tulchinsky Y, Fridman N, Börner A, Gandelman M. Synthesis and Characteristics of Iridium Complexes Bearing N-Heterocyclic Nitrenium Cationic Ligands. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00220] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Heroot Levy Vahav
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Alla Pogoreltsev
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Yuri Tulchinsky
- Institute of Chemistry, The Hebrew University, Edmond Safra Campus, Jerusalem 91904, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Armin Börner
- Leibniz-Institut für Katalyse e.V., A.-Einstein-Strasse 29a, 18059 Rostock, Germany
- Institut für Chemie, Universität Rostock, A.-Einstein-Strasse 3a, 18059 Rostock, Germany
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
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23
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Yadav S, Deka R, Raju S, Singh HB. Synthesis of N-heterocyclic nitrenium (NHN) ions and related donor systems: Coordination with d10-metal ions. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.01.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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24
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Falvey DE. Discrete Existence of Singlet Nitrenium Ions Revisited: Computational Studies of Non-Aryl Nitrenium Ions and Their Rearrangements. ACS OMEGA 2018; 3:10418-10432. [PMID: 31459169 PMCID: PMC6645317 DOI: 10.1021/acsomega.8b01038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 08/08/2018] [Indexed: 06/10/2023]
Abstract
Nitrenium ion species are examined using computational methods (DFT, MP2, coupled-cluster, and a composite method, CBS-APNO) with a particular emphasis on nonaromatic species (i.e., those lacking an aromatic or heteroaromatic ring in direct conjugation with the formal nitrenium ion center.) The substitution of the N+ center with alkyl, alkoxy, vinyl, acyl, and sulfonyl, among others, was evaluated. For these species, three properties are considered. (1) The stability of the nitrenium ions to unimolecular isomerizations such as 1,2 alkyl or H shifts; to the extent that the singlet states could be characterized as discrete minima on the potential energy surface (PES), (2) the effect of the substituents on singlet-triplet energy splitting as well as (3) the relative stabilities of the nitrenium ions as defined by N-hydration enthalpies (RR'N+ + H2O → RR'NOH2 +). Nearly all simple alkyl and di-alkyl nitrenium ion singlet states are predicted to rearrange without detectable barriers, largely through 1,2 H or alkyl shifts. Methyl and N,N-dimethylnitrenium ion singlet states could be characterized as formal minima on the PES. However, these species show small or insignificant barriers to isomerization. Disubstituted nitrenium ions that include an alkyl group and a conjugating substituent such as alkoxyl, vinyl, or phenyl show meaningful barriers to isomerization and are thus predicted to possess nontrivial lifetimes in solution. Alkyl groups substantially stabilize the singlet state relative to the situation in the parent nitrenium ion NH2 + to the point where the two states are nearly degenerate. Other groups that interact with the nitrenium ion center decrease the ΔE st in the order formoyl < vinyl < phenyl < alkoxy ∼ sulfonyl < cyclopropyl ∼ cyclobutyl. The latter two substituents interact strongly with the (singlet) nitrenium ion center through the formation of a nonclassical bonding reminiscent of the bisected cyclopropylcarbinyl ion case for carbocations. When singlet-state stability is evaluated in the context of N-hydration enthalpies, it is found that the ordering is acyl < vinyl < alkoxyl < phenyl < cyclopropyl and cyclobutyl.
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Affiliation(s)
- Daniel E. Falvey
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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25
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Ullah SS, Kashyap C, Guha AK. Moving towards Nitrogen-Based Lewis Acids: A Theoretical Study. ChemistrySelect 2018. [DOI: 10.1002/slct.201801145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Sabnam S. Ullah
- Department of Chemistry; Cotton University, Panbazar; Guwahati, Assam INDIA - 781001
| | - Chayanika Kashyap
- Department of Chemistry; Cotton University, Panbazar; Guwahati, Assam INDIA - 781001
| | - Ankur K. Guha
- Department of Chemistry; Cotton University, Panbazar; Guwahati, Assam INDIA - 781001
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26
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Zhou J, Liu LL, Cao LL, Stephan DW. An umpolung of Lewis acidity/basicity at nitrogen by deprotonation of a cyclic (amino)(aryl)nitrenium cation. Chem Commun (Camb) 2018. [PMID: 29527605 DOI: 10.1039/c8cc01331d] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A cyclic (amino)(aryl)nitrenium cation 2 has been achieved by treatment of spiro[fluorene-9,3'-indazole] (1) with Ph2CHCl and AgBF4. This cation 2 is Lewis acidic at nitrenium N1, reacting with PMe3 affording a Lewis acid/base adduct 3. In contrast, deprotonation of 2 with other bases provides a neutral compound 4 which is Lewis basic at N1, reacting with electrophiles including GaCl3, MeOTf and PhNCO.
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Affiliation(s)
- Jiliang Zhou
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario M5S 3H6, Canada.
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Thomas CM, Hatzis GP, Pepi MJ. Examining the effects of variations in ligand framework and pnictogen substitution on the geometry and electronic structure of metal complexes of N-heterocyclic phosphido ligands incorporated into a diphosphine pincer ligand framework. Polyhedron 2018. [DOI: 10.1016/j.poly.2017.11.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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Zhou J, Liu LL, Cao LL, Stephan DW. Nitrogen-Based Lewis Acids: Synthesis and Reactivity of a Cyclic (Alkyl)(Amino)Nitrenium Cation. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201713118] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Jiliang Zhou
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | - Liu Leo Liu
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | - Levy L. Cao
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
| | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George St. Toronto Ontario M5S3H6 Canada
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Zhou J, Liu LL, Cao LL, Stephan DW. Nitrogen-Based Lewis Acids: Synthesis and Reactivity of a Cyclic (Alkyl)(Amino)Nitrenium Cation. Angew Chem Int Ed Engl 2018; 57:3322-3326. [PMID: 29397010 DOI: 10.1002/anie.201713118] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 02/01/2018] [Indexed: 01/08/2023]
Abstract
A room-temperature-stable crystalline cyclic (alkyl)(amino)nitrenium cation 2 features cationic nitrogen atom with a smaller HOMO-LUMO gap compared to that of a 1,2,3-triazolium 5 (an N-heterocyclic nitrenium cation). The low-lying LUMO of 2 results in an enhanced electrophilicity, which allowed for the formation of Lewis adducts with neutral Lewis bases, such as Me3 P, nBu3 P, and IiPr. The N-based Lewis acid 2 also forms an FLP with tBu3 P but subsequently reacts with (PrS)2 to cleave the S-S bond. Both experimental and theoretical results suggest that the Lewis acidity of 2 is stronger than its N3 analogues.
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Affiliation(s)
- Jiliang Zhou
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada
| | - Liu Leo Liu
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada
| | - Levy L Cao
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada
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31
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Iglesias-Sigüenza J, Izquierdo C, Díez E, Fernández R, Lassaletta JM. N-Heterotricyclic cationic carbene ligands. Synthesis, reactivity and coordination chemistry. Dalton Trans 2018. [PMID: 29528072 DOI: 10.1039/c8dt00213d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal complexes based on cationic N-heterotricyclic carbenes have been synthesized and the impact of charge delocalization on their electronic properties has been analysed.
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Affiliation(s)
- Javier Iglesias-Sigüenza
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - Cristina Izquierdo
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - Elena Díez
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - Rosario Fernández
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - José M. Lassaletta
- Instituto Investigaciones Químicas (CSIC-USe) and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41092 Sevilla
- Spain
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32
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Gu L, Wolf LM, Zieliński A, Thiel W, Alcarazo M. α-Dicationic Chelating Phosphines: Synthesis and Application to the Hydroarylation of Dienes. J Am Chem Soc 2017; 139:4948-4953. [PMID: 28322057 DOI: 10.1021/jacs.7b01441] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A series of new P^P-chelating ligands constituted by a dicationic -[P(H2Im)2]+2 unit (H2Im = 1,3-dimethyl-4,5-dihydroimidazol-2-ylidene) and a -PPh2 group connected through structurally different backbones have been synthesized. Evaluation of their reactivity toward different metal centers provides evidence that the dicationic fragment, otherwise reluctant to coordinate metals, readily participates in the formation of chelates when embedded into such a scaffold. Moreover, it significantly enhances the Lewis acidity of the metals to which it coordinates. This property has been used to develop a Rh catalyst that efficiently triggers the hydroarylation of dienes with electron-rich aromatic molecules. Kinetic studies and deuterium-labeling experiments, as well as density functional theory calculations, were performed in order to rationalize these findings.
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Affiliation(s)
- Lianghu Gu
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen , Tammannstraße 2, 37077 Göttingen, Germany
| | - Lawrence M Wolf
- Department of Chemistry, University of Massachusetts Lowel , Lowell, Massachusetts 01854, United States
| | - Adam Zieliński
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen , Tammannstraße 2, 37077 Göttingen, Germany
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Manuel Alcarazo
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen , Tammannstraße 2, 37077 Göttingen, Germany
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Abstract
Being a major conception of chemistry, Lewis acids have found countless applications throughout chemical enterprise. Although many chemical elements can serve as the central atom of Lewis acids, nitrogen is usually associated with Lewis bases. Here, we report on the first example of robust and modifiable Lewis acids centered on the nitrogen atom, which provide stable and well-characterized adducts with various Lewis bases. On the basis of the reactivity of nitrogen Lewis acids, we prepared, for the first time, cyclic triazanes, a class of cyclic organic compounds sequentially bearing three all-saturated nitrogen atoms (N-N-N motif). Reactivity abilities of these N-Lewis acids were explained by theoretical calculations. Properties and future applications of nitrogen Lewis acids are intriguing.
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Affiliation(s)
- Alla Pogoreltsev
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology , Technion City, Haifa 32000, Israel
| | - Yuri Tulchinsky
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology , Technion City, Haifa 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology , Technion City, Haifa 32000, Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology , Technion City, Haifa 32000, Israel
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Campos J, López-Serrano J, Peloso R, Carmona E. Methyl Complexes of the Transition Metals. Chemistry 2016; 22:6432-57. [PMID: 26991740 DOI: 10.1002/chem.201504483] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Indexed: 01/11/2023]
Abstract
Organometallic chemistry can be considered as a wide area of knowledge that combines concepts of classic organic chemistry, that is, based essentially on carbon, with molecular inorganic chemistry, especially with coordination compounds. Transition-metal methyl complexes probably represent the simplest and most fundamental way to view how these two major areas of chemistry combine and merge into novel species with intriguing features in terms of reactivity, structure, and bonding. Citing more than 500 bibliographic references, this review aims to offer a concise view of recent advances in the field of transition-metal complexes containing M-CH3 fragments. Taking into account the impressive amount of data that are continuously provided by organometallic chemists in this area, this review is mainly focused on results of the last five years. After a panoramic overview on M-CH3 compounds of Groups 3 to 11, which includes the most recent landmark findings in this area, two further sections are dedicated to methyl-bridged complexes and reactivity.
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Affiliation(s)
- Jesús Campos
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Joaquín López-Serrano
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain
| | - Riccardo Peloso
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain
| | - Ernesto Carmona
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain.
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Pazio A, Woźniak K, Grela K, Trzaskowski B. Nitrenium ions and trivalent boron ligands as analogues of N-heterocyclic carbenes in olefin metathesis: a computational study. Dalton Trans 2015; 44:20021-6. [PMID: 26525899 DOI: 10.1039/c5dt03446a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We used the density functional theory to evaluate the suitability of nitrenium ions and trivalent boron ligands as analogues of N-heterocyclic carbenes in ruthenium-based metathesis catalysts. We demonstrate that these analogues induce only minor structural changes in Hoveyda-Grubbs-like precatalysts, but have major impact on precatalyst initiation. Nitrenium ion-modified precatalysts are characterized by a weak Ru-N bond resulting in a relatively strong Ru-O bond and large free energy barriers for initiation, making them good candidates for efficient latent Ru-based catalysts. On the other hand the trivalent boron ligand, bearing a formal -1 charge, binds strongly to the ruthenium ion, weakening the Ru-O bond and facilitating its dissociation, to promote fast reaction initiation. We show that the calculated bond dissociation energy of the Ru-C/N/B bond may serve as an accurate indicator of the Ru-O bond strength and the rate of metathesis initiation.
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Affiliation(s)
- A Pazio
- Centre of New Technologies, University of Warsaw, 02-097 Warszawa, Poland. and Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, 02-093 Warszawa, Poland
| | - K Woźniak
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, 02-093 Warszawa, Poland
| | - K Grela
- Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, 02-093 Warszawa, Poland
| | - B Trzaskowski
- Centre of New Technologies, University of Warsaw, 02-097 Warszawa, Poland.
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36
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Coordination Chemistry of N-Heterocyclic Nitrenium-Based Ligands. Chemistry 2015; 21:7099-110. [DOI: 10.1002/chem.201405526] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Indexed: 11/07/2022]
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Petronilho A, Llobet A, Albrecht M. Ligand Exchange and Redox Processes in Iridium Triazolylidene Complexes Relevant to Catalytic Water Oxidation. Inorg Chem 2014; 53:12896-901. [DOI: 10.1021/ic501894u] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Ana Petronilho
- School of Chemistry
and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland
| | - Antoni Llobet
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Martin Albrecht
- School of Chemistry
and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland
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Petronilho A, Woods JA, Mueller-Bunz H, Bernhard S, Albrecht M. Iridium Complexes Containing Mesoionic C Donors: Selective C(sp3)H versus C(sp2)H Bond Activation, Reactivity Towards Acids and Bases, and Catalytic Oxidation of Silanes and Water. Chemistry 2014; 20:15775-84. [PMID: 25302630 DOI: 10.1002/chem.201404776] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Ana Petronilho
- School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4 (Ireland)
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39
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Albrecht M. Normal and Abnormal N-Heterocyclic Carbene Ligands. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2014. [DOI: 10.1016/b978-0-12-800976-5.00002-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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