1
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Werner L, Radius U. NHC aluminum chemistry on the rise. Dalton Trans 2024. [PMID: 39225565 DOI: 10.1039/d4dt01660b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
This perspective highlights recent developments of the use of N-heterocyclic carbenes (NHCs) and cyclic (alkyl)(amino)carbenes (cAACs) in alane and aluminum organyl chemistry. Especially in the last few years this flourishing research field led to some remarkable discoveries including various substitution patterns at the central aluminum atom, different oxidation states, neutral and charged compounds with varying coordination numbers and unique reactivities. Thereby NHCs play a vital role in the stabilization of these otherwise highly reactive compounds, which would not be realizable without the use of this intriguing class of ligands. Nevertheless, main group hydrides and especially NHC ligated alanes also tend to undergo NHC decomposition reactions, which are part of ongoing research and provide important information for NHC research in general.
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Affiliation(s)
- Luis Werner
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Udo Radius
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
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2
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Madron du Vigné A, Cramer N. Streamlined synthetic assembly of α-chiral CAAC ligands and catalytic performance of their copper and ruthenium complexes. Chem Sci 2024:d4sc04278f. [PMID: 39129771 PMCID: PMC11306997 DOI: 10.1039/d4sc04278f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Accepted: 07/23/2024] [Indexed: 08/13/2024] Open
Abstract
The unique electronic and steric parameters of chiral cyclic alkyl amino carbene (CAAC) ligands render them appealing steering ligands for enantioselective transition-metal catalyzed transformations. Due to the lack of efficient synthetic strategies to access particularly attractive α-chiral CAACs assessment and exploitation of their full synthetic potential remain difficult. Herein, we report a streamlined strategy to assemble a library of diastereo- and enantiomerically pure CAAC ligands featuring the notoriously difficult to access α-quaternary stereogenic centers. A tailored Julia-Kocienski olefination reagent allows the Claisen-rearrangement to be leveraged as an expedient route to form the synthetically pivotal racemic α-chiral methallyl aldehydes. Subsequent condensation with chiral amines and further cyclization provided a library of diastereomeric mixtures of the targeted ligand precursors. The CAAC salts as well as their corresponding metal complexes are conveniently separable by standard silica gel flash chromatography closing a long-standing accessibility gap in chiral CAAC ligands with proximal α-chirality. The rapid availability of both diastereomers enables testing of the relevance and synergistic effects of two chiral centers on the ligand in catalytic applications. A broad range of metal complexes with copper, gold, rhodium and ruthenium were obtained and structurally analyzed. The catalytic performances of the corresponding chiral CAAC copper and ruthenium complexes were assessed in enantioselective conjugate borylations and asymmetric ring closing metathesis, displaying selectivities of up 95 : 5 er.
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Affiliation(s)
- Adrien Madron du Vigné
- Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Nicolai Cramer
- Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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3
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Talcik J, Serrato MR, Del Vecchio A, Colombel-Rouen S, Morvan J, Roisnel T, Jazzar R, Melaimi M, Bertrand G, Mauduit M. Cyclic (amino)(barrelene)carbene Ru-complexes: synthesis and reactivity in olefin metathesis. Dalton Trans 2024; 53:5346-5350. [PMID: 38450432 DOI: 10.1039/d4dt00102h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
The synthesis of ruthenium-complexes with cyclic (amino)(barrelene)carbenes (namely CABCs) as ligands is reported. Isolated in moderate to good yields, these new complexes showed impressive thermal stability at 110 °C over several days. Good catalytic performances were demonstrated in various ring-closing metathesis (RCM), macrocyclic-RCM, ring-closing enyne metathesis (RCEYM), cross-metathesis (CM), and ring-opening cross metathesis (ROCM) reactions.
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Affiliation(s)
- Jakub Talcik
- Univ. Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France.
| | - Melinda R Serrato
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, USA.
| | - Antonio Del Vecchio
- Univ. Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France.
| | - Sophie Colombel-Rouen
- Univ. Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France.
| | - Jennifer Morvan
- Univ. Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France.
| | - Thierry Roisnel
- Univ. Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France.
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, USA.
| | - Mohand Melaimi
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, USA.
| | - Guy Bertrand
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, USA.
| | - Marc Mauduit
- Univ. Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France.
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4
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Vermersch F, Wang VT, Abdellaoui M, Jazzar R, Bertrand G. Ambiphilicity of ring-expanded N-heterocyclic carbenes. Chem Sci 2024; 15:3707-3710. [PMID: 38455021 PMCID: PMC10915854 DOI: 10.1039/d3sc04543a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 01/18/2024] [Indexed: 03/09/2024] Open
Abstract
N-heterocyclic carbenes, such as imidazole-2-ylidenes and imidazolin-2-ylidenes, the popular class of singlet carbenes introduced by Arduengo in 1991 have not been shown to be ambiphilic owing to the two σ-withdrawing, π-donating amino groups flanking the carbene centre. However, our experimental data suggest that ring-expanded N-heterocyclic carbenes (RE-NHCs), especially the seven and eight membered rings, are significantly ambiphilic. Our results also show that the steric environment in RE-NHCs can become a determining factor for controlling the E-H bond activation.
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Affiliation(s)
- François Vermersch
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Victor T Wang
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Mehdi Abdellaoui
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
| | - Guy Bertrand
- UCSD-CNRS Joint Research Chemistry Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California La Jolla San Diego California 92093-0358 USA
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5
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Zhao Q, Rahman MM, Zhou T, Yang S, Lalancette R, Szostak R, Szostak M. Wingtip-Flexible N-Heterocyclic Carbenes: Unsymmetrical Connection between IMes and IPr. Angew Chem Int Ed Engl 2024; 63:e202318703. [PMID: 38135660 PMCID: PMC10922840 DOI: 10.1002/anie.202318703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 12/24/2023]
Abstract
IMes (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) and IPr (IPr=1,3- bis(2,6-diisopropylphenyl)imidazol-2-ylidene) represent by far the most frequently used N-heterocyclic carbene ligands in homogeneous catalysis, however, despite numerous advantages, these ligands are limited by the lack of steric flexibility of catalytic pockets. We report a new class of unique unsymmetrical N-heterocyclic carbene ligands that are characterized by freely-rotatable N-aromatic wingtips in the imidazol-2-ylidene architecture. The combination of rotatable N-CH2 Ar bond with conformationally-fixed N-Ar linkage results in a highly modular ligand topology, entering the range of geometries inaccessible to IMes and IPr. These ligands are highly reactive in Cu(I)-catalyzed β-hydroboration, an archetypal borylcupration process that has had a transformative impact on the synthesis of boron-containing compounds. The most reactive Cu(I)-NHC in this class has been commercialized in collaboration with MilliporeSigma to enable broad access of the synthetic chemistry community. The ligands gradually cover %Vbur geometries ranging from 37.3 % to 52.7 %, with the latter representing the largest %Vbur described for an IPr analogue, while retaining full flexibility of N-wingtip. Considering the modular access to novel geometrical space in N-heterocyclic carbene catalysis, we anticipate that this concept will enable new opportunities in organic synthesis, drug discovery and stabilization of reactive metal centers.
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Affiliation(s)
- Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Tongliang Zhou
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Shiyi Yang
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383 (Poland)
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102 (United States)
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6
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Ohashi M, Ando K, Murakami S, Michigami K, Ogoshi S. N-Heterocyclic Carbenes with Polyfluorinated Groups at the 4- and 5-Positions from [3 + 2] Cycloadditions between Formamidinates and cis-1,2-Difluoroalkene Derivatives. J Am Chem Soc 2023; 145:23098-23108. [PMID: 37749910 DOI: 10.1021/jacs.3c06331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/27/2023]
Abstract
We herein report the formation of fluorinated N-heterocyclic carbenes (NHCFs) that bear fluorine atoms at the 4- and 5-positions of the imidazol-2-ylidene ring. Treatment of sodium N,N'-bis(aryl)formamidinates with tetrafluoroethylene followed by the addition of LiBF4 induced a [3 + 2] cycloaddition to afford 4,5-difluorinated imidazolium salts, which served as the precursors for 4,5-difluorinated NHCs. A key feature of this procedure is its applicability to other perfluorinated compounds, which enabled us to incorporate polyfluorinated functional groups at 4- and 5-positions on the imidazol-2-ylidene skeleton. Thus, employing octafluorocyclopentene and hexafluorobenzene led to the formation of 4,4,5,5,6,6-hexafluoro-1,3-diaryl-3,4,5,6-tetrahydrocyclopenta[d]imidazolium (CypIPrF·HBF4) and 4,5,6,7-tetrafluoro-1,3-diarylbenzimidazolium (BIPrF·HBF4) salts, respectively. A thorough NMR analysis of these NHCFs, their selenium adducts, and their tricarbonyl nickel complexes, (NHCF)Ni(CO)3, demonstrated that the fluorine substituents, contrary to expectations, tend to act as electron donors owing to the considerable positive mesomeric effect, while the perfluorocyclopentene-fused and tetrafluorobenzo-fused rings are pure electron acceptors due to their strong negative inductive effect. The unique and increased π-accepting character of the perfluorocyclopentene-fused and tetrafluorobenzo-fused NHCFs in both stoichiometric and catalytic reactions is further demonstrated by employing (NHCF)Ni(CO)3 and (NHCF)AuCl species, respectively. Moreover, an analysis of the % buried volume (%Vbur) values clearly suggests that the modification of the NHC backbone with polyfluorinated groups can drastically alter the electronic properties of the NHC ligand without substantially changing its steric properties. Our experimental results were further corroborated by a series of computational calculations.
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Affiliation(s)
- Masato Ohashi
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, Sakai 599-8531 Osaka, Japan
| | - Kota Ando
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita 565-0871 Osaka, Japan
| | - Shoichi Murakami
- Department of Chemistry, Faculty of Science, Osaka Prefecture University, Sakai 599-8531 Osaka, Japan
| | - Kenichi Michigami
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, Sakai 599-8531 Osaka, Japan
| | - Sensuke Ogoshi
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita 565-0871 Osaka, Japan
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7
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Horrer G, Luff MS, Radius U. N-Heterocyclic carbene and cyclic (alkyl)(amino)carbene ligated half-sandwich complexes of chromium(II) and chromium(I). Dalton Trans 2023; 52:13244-13257. [PMID: 37667868 DOI: 10.1039/d3dt02123h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
The synthesis and characterization of a series of Cr(II) N-Heterocyclic Carbene (NHC) complexes of the type [{Cr(NHC)Cl(μ-Cl)}2] and [(Cyp)Cr(NHC)X] (Cyp = η5-C5H5, cyclopentadienyl; η5-C5Me5, pentamethylcyclopentadienyl; X = Cl, η3-C3H5; NHC = IMeMe, IiPrMe, IMes, IDipp) as well as the cyclic (alkyl)(amino)carbene cAACMe ligated complexes [(η5-C5H5)Cr(cAACMe)X] (X = Cl, NPh2), [(η5-C9H7)Cr(cAACMe)Cl] (C9H7 = Ind, indenyl) and [(η5-C13H9)Cr(cAACMe)Cl] (C13H9 = Fl, fluorenyl) are reported. The reduction of [(η5-C5Me5)Cr(IMeMe)Cl] with KC8 in the presence of CO afforded the NHC ligated Cr(I) metallo-radical [(η5-C5Me5)Cr(IMeMe)(CO)2]. Quantum chemical calculations performed on [(η5-C5Me5)Cr(IMeMe)(CO)2] confirm for this complex a predominantly chromium centered radical.
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Affiliation(s)
- Günther Horrer
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Martin S Luff
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Udo Radius
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
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8
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Rahman M, Gao P, Zhao Q, Lalancette R, Szostak R, Szostak M. [Au(Np #)Cl]: Highly Reactive and Broadly Applicable Au(I)─NHC Catalysts for Alkyne π-Activation Reactions. Catal Sci Technol 2023; 13:5131-5139. [PMID: 38464950 PMCID: PMC10923537 DOI: 10.1039/d3cy00717k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Cationic Au(I)─NHC (NHC = N-heterocyclic carbene) complexes have become an important class of catalysts for alkyne π-activation reactions in organic synthesis. In particular, these complexes are characterized by high stability of catalytic species engendered by strong σ-donation and metal backbonding. Herein, we report the synthesis and characterization of well-defined [Au(NHC)Cl] complexes featuring recently discovered IPr# family of ligands that hinge upon modular peralkylation of aniline. These ligands have been commercialized in collaboration with MilliporeSigma (IPr#: 915653; Np#: 915912; BIAN-IPr#: 916420). Evaluation of the [Au(NHC)Cl] complexes in a series of Au(I)─NHC-catalyzed π-functionalizations of alkynes, such as hydrocarboxylation, hydroamination and hydration, resulted in the identification of wingtip-flexible [Au(Np#)Cl] as a highly reactive and broadly applicable catalyst with the re-activity outperforming the classical [Au(IPr)Cl] and [Au(IPr*)Cl] complexes. The utility of this catalyst has been demonstrated in the direct late-stage derivatization of complex pharmaceuticals. Structural and computational studies were conducted to determine steric effects, frontier molecular orbitals and bond orders of this class of catalysts. Considering the attractive features of well-defined Au(I)─NHC complexes, we anticipate that this class of bulky and wingtip-flexible Au(I)─NHCs based on the modular peralkylated naphthylamine scaffold will find broad application in π-functionalization of alkynes in various areas of organic synthesis and catalysis.
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Affiliation(s)
- Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, United States
| | - Pengcheng Gao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, United States
| | - Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, United States
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, United States
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9
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Thangavadivale VG, Tendera L, Bertermann R, Radius U, Beweries T, Perutz RN. Solution and solid-state studies of hydrogen and halogen bonding with N-heterocyclic carbene supported nickel(II) fluoride complexes. Faraday Discuss 2023; 244:62-76. [PMID: 37097153 DOI: 10.1039/d2fd00171c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Nickel fluoride complexes of the type [Ni(F)(L)2(ArF)] (L = phosphine, ArF = fluorinated arene) are well-known to form strong halogen and hydrogen bonds in solution and in the solid state. A comprehensive study of such non-covalent interactions using bis(carbene) complexes as acceptors and suitable halogen and hydrogen bond donors is presented. In solution, the complex [Ni(F)(iPr2Im)2(C6F5)] forms halogen and hydrogen bonds with iodopentafluorobenzene and indole, respectively, which have formation constants (K300) an order of magnitude greater than those of structurally related phosphine supported nickel fluorides. Co-crystallisation of this complex and its backbone-methylated analogue [Ni(F)(iPr2Me2Im)2(C6F5)] with 1,4-diiodotetrafluorobenzene produces halogen bonding adducts which were characterised by X-ray analysis and 19F MAS solid state NMR analysis. Differences in the chemical shifts between the nickel fluoride and its halogen bonding adduct are well in line with data that were obtained from titration studies in solution.
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Affiliation(s)
| | - Lukas Tendera
- Institut für Anorganische Chemie, Julius-Maximilians-Universität, Am Hubland, 97074 Würzburg, Germany.
| | - Rüdiger Bertermann
- Institut für Anorganische Chemie, Julius-Maximilians-Universität, Am Hubland, 97074 Würzburg, Germany.
| | - Udo Radius
- Institut für Anorganische Chemie, Julius-Maximilians-Universität, Am Hubland, 97074 Würzburg, Germany.
| | - Torsten Beweries
- Leibniz-Institut für Katalyse, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
| | - Robin N Perutz
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
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10
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Marigo N, Morgenstern B, Biffis A, Munz D. (CAAC)Pd(py) Catalysts Disproportionate to Pd(CAAC) 2. Organometallics 2023; 42:1567-1572. [PMID: 37448536 PMCID: PMC10337258 DOI: 10.1021/acs.organomet.3c00150] [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: 03/21/2023] [Indexed: 07/15/2023]
Abstract
Palladium complexes with one N-heterocyclic carbene (NHC) and a pyridine ancillary ligand are powerful cross-coupling precatalysts. Herein, we report such complexes with a cyclic (alkyl)(amino)carbene (CAAC) ligand replacing the NHC. We find that the alleged reduced form, (CAAC)Pd(py), disproportionates to the (CAAC)2Pd0 complex and palladium nanoparticles. This notwithstanding, they are potent catalysts in the Buchwald-Hartwig amination with aryl chlorides under mild conditions (60 °C). In the presence of dioxygen, these complexes catalyze the formation of diazenes from anilines. The catalytic activities of the NHC- and CAAC-supported palladium(0) and palladium(II) complexes are similar in the cross-coupling reaction, yet the CAAC complexes are superior for diazene formation.
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Affiliation(s)
- Nicola Marigo
- Coordination
Chemistry, Saarland University, Campus C4.1, Saarbrücken D-66123, Germany
- Department
of Chemical Sciences, University of Padova, Via Marzolo 1, Padova I-35131, Italy
| | - Bernd Morgenstern
- Coordination
Chemistry, Saarland University, Campus C4.1, Saarbrücken D-66123, Germany
| | - Andrea Biffis
- Department
of Chemical Sciences, University of Padova, Via Marzolo 1, Padova I-35131, Italy
| | - Dominik Munz
- Coordination
Chemistry, Saarland University, Campus C4.1, Saarbrücken D-66123, Germany
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11
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Rahman MM, Meng G, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. I tOct (I tOctyl) - pushing the limits of I tBu: highly hindered electron-rich N-aliphatic N-heterocyclic carbenes. Chem Sci 2023; 14:5141-5147. [PMID: 37206400 PMCID: PMC10189875 DOI: 10.1039/d3sc01006f] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 04/15/2023] [Indexed: 05/21/2023] Open
Abstract
ItBu (ItBu = 1,3-di-tert-butylimidazol-2-ylidene) represents the most important and most versatile N-alkyl N-heterocyclic carbene available in organic synthesis and catalysis. Herein, we report the synthesis, structural characterization and catalytic activity of ItOct (ItOctyl), C2-symmetric, higher homologues of ItBu. The new ligand class, including saturated imidazolin-2-ylidene analogues has been commercialized in collaboration with MilliporeSigma: ItOct, 929 298; SItOct, 929 492 to enable broad access of the academic and industrial researchers within the field of organic and inorganic synthesis. We demonstrate that replacement of the t-Bu side chain with t-Oct results in the highest steric volume of N-alkyl N-heterocyclic carbenes reported to date, while retaining the electronic properties inherent to N-aliphatic ligands, such as extremely strong σ-donation crucial to the reactivity of N-alkyl N-heterocyclic carbenes. An efficient large-scale synthesis of imidazolium ItOct and imidazolinium SItOct carbene precursors is presented. Coordination chemistry to Au(i), Cu(i), Ag(i) and Pd(ii) as well as beneficial effects on catalysis using Au(i), Cu(i), Ag(i) and Pd(ii) complexes are described. Considering the tremendous importance of ItBu in catalysis, synthesis and metal stabilization, we anticipate that the new class of ItOct ligands will find wide application in pushing the boundaries of new and existing approaches in organic and inorganic synthesis.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Guangrong Meng
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Elwira Bisz
- Department of Chemistry, Opole University 48 Oleska Street Opole 45-052 Poland
| | - Błażej Dziuk
- Department of Chemistry, Wroclaw University of Science and Technology Norwida 4/6 14 Wroclaw 50-373 Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University F. Joliot-Curie 14 Wroclaw 50-383 Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
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12
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Termühlen S, Dutschke PD, Hepp A, Hahn FE. Synthesis of CAAC Complexes by Oxidative Addition of 2-Chloro-3,3-dimethyl- N-ethylindoleninium Cations to Carbonylmetalates and Subsequent Transmetalation. Organometallics 2023. [DOI: 10.1021/acs.organomet.3c00043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Affiliation(s)
- Sebastian Termühlen
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 30, D-48149 Münster, Germany
| | - Patrick D. Dutschke
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 30, D-48149 Münster, Germany
| | - Alexander Hepp
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 30, D-48149 Münster, Germany
| | - F. Ekkehardt Hahn
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 30, D-48149 Münster, Germany
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13
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Mulks FF, Melaimi M, Yan X, Baik MH, Bertrand G. How To Enhance the Efficiency of Breslow Intermediates for SET Catalysis. J Org Chem 2023; 88:2535-2542. [PMID: 36719963 DOI: 10.1021/acs.joc.2c02978] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Oxidative carbene organocatalysis, which proceeds via single electron transfer (SET) pathways, has been limited by the moderately reducing properties of deprotonated Breslow intermediates BI-s derived from thiazol-2-ylidene 1 and 1,2,4-triazolylidene 2. Using computational methods, we assess the redox potentials of BI-s based on ten different types of known stable carbenes and report our findings concerning the key parameters influencing the steps of the catalytic cycle. From the calculated values of the first oxidation potential of BI-s derived from carbenes 1 to 10, it appears that, apart from the diamidocarbene 7, all the others are more reducing than thiazol-2-ylidene 1 and the 1,2,4-triazolylidene 2. We observed that while the reducing power of BI-s significantly decreases with increasing solvent polarity, the redox potential of the oxidant can increase at a greater rate, thus facilitating the reaction. The cation, associated with the base, also plays an important role when a nonpolar solvent is used; large and weakly coordinating cations such as Cs+ are beneficial. The radical-radical coupling step is probably the most challenging step due to both electronic and steric constraints. Based on our results, we predict that mesoionic carbene 3 and abnormal NHC 4 are the most promising candidates for oxidative carbene organocatalysis.
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Affiliation(s)
- Florian F Mulks
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea.,Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,UCSD-CNRS Joint Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Mohand Melaimi
- UCSD-CNRS Joint Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Xiaoyu Yan
- Department of Chemistry, Renmin University of China, Beijing 100872, People's Republic of China
| | - Mu-Hyun Baik
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea.,Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Guy Bertrand
- UCSD-CNRS Joint Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
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14
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Philipp MSM, Bertermann R, Radius U. Activation of Ge-H and Sn-H Bonds with N-Heterocyclic Carbenes and a Cyclic (Alkyl)(amino)carbene. Chemistry 2023; 29:e202202493. [PMID: 36177710 PMCID: PMC10100474 DOI: 10.1002/chem.202202493] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Indexed: 01/14/2023]
Abstract
A study of the reactivity of several N-heterocyclic carbenes (NHCs) and the cyclic (alkyl)(amino)carbene 1-(2,6-di-iso-propylphenyl)-3,3,5,5-tetramethyl-pyrrolidin-2-ylidene (cAACMe ) with the group 14 hydrides GeH2 Mes2 and SnH2 Me2 (Me=CH3 , Mes=1,3,5-(CH3 )3 C6 H2 ) is presented. The reaction of GeH2 Mes2 with cAACMe led to the insertion of cAACMe into one Ge-H bond to give cAACMe H-GeHMes2 (1). If 1,3,4,5-tetramethyl-imidazolin-2-ylidene (Me2 ImMe ) was used as the carbene, NHC-mediated dehydrogenative coupling occurred, which led to the NHC-stabilized germylene Me2 ImMe ⋅GeMes2 (2). The reaction of SnH2 Me2 with cAACMe also afforded the insertion product cAACMe H-SnHMe2 (3), and reaction of two equivalents Me2 ImMe with SnH2 Me2 gave the NHC-stabilized stannylene Me2 ImMe ⋅SnMe2 (4). If the sterically more demanding NHCs Me2 ImMe , 1,3-di-isopropyl-4,5-dimethyl-imidazolin-2-ylidene (iPr2 ImMe ) and 1,3-bis-(2,6-di-isopropylphenyl)-imidazolin-2-ylidene (Dipp2 Im) were employed, selective formation of cyclic oligomers (SnMe2 )n (5; n=5-8) in high yield was observed. These cyclic oligomers were also obtained from the controlled decomposition of cAACMe H-SnHMe2 (3).
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Affiliation(s)
- Michael S. M. Philipp
- Institute of Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Rüdiger Bertermann
- Institute of Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Udo Radius
- Institute of Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
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15
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Rahman MM, Zhao Q, Meng G, Szostak R, Szostak M. [Ni(Np#)(η5-Cp)Cl]: Flexible, Sterically Bulky, Well-Defined, Highly Reactive Complex for Nickel-Catalyzed Cross-Coupling. Organometallics 2022; 41:2597-2604. [PMID: 38031540 PMCID: PMC10686542 DOI: 10.1021/acs.organomet.2c00316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ni-NHCs (NHC = N-heterocyclic carbene) have become an increasingly important class of complexes in catalysis and organometallic chemistry owing to the beneficial features of nickel as an abundant 3d metal. However, the development of well-defined and air-stable Ni-NHC complexes for cross-coupling has been more challenging than with Pd-NHC catalysis because of less defined reactivity trends of NHC ancillary ligands coordinated to Ni. Herein, we report the synthesis and catalytic activity of well-defined [Ni(NHC)(η5-Cp)Cl] complexes bearing recently commercialized IPr# family of ligands (Sigma Aldrich) and versatile cyclopentadienyl throw-away ligand. The NHC ligands, IPr#, Np# and BIAN-IPr#, are prepared by robust and modular peralkylation of anilines. Most crucially, we identified [Ni(Np#)(η5-Cp)Cl] as a highly reactive [Ni(NHC)(η5-Cp)Cl] complex, with the reactivity outperforming the classical [Ni(IPr)(η5-Cp)Cl] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene). These [Ni(NHC)(η5-Cp)Cl] precatalysts were employed in the Suzuki and Kumada cross-coupling of aryl chlorides and aryl bromides. Computational studies were conducted to determine steric effect and bond order analysis. Considering the attractive features of well-defined Ni-NHCs, we anticipate that this class of bulky and flexible Ni-NHC catalysts will find broad application in organic synthesis and catalysis.
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Affiliation(s)
- Md Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Guangrong Meng
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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16
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Madron du Vigné A, Cramer N. Chiral Cyclic Alkyl Amino Carbene (CAAC) Transition-Metal Complexes: Synthesis, Structural Analysis, and Evaluation in Asymmetric Catalysis. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Adrien Madron du Vigné
- Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), SB-ISIC, BCH 4305, 1015 Lausanne, Switzerland
| | - Nicolai Cramer
- Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), SB-ISIC, BCH 4305, 1015 Lausanne, Switzerland
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17
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Breitwieser K, Bahmann H, Weiss R, Munz D. Gauging Radical Stabilization with Carbenes. Angew Chem Int Ed Engl 2022; 61:e202206390. [PMID: 35796423 PMCID: PMC9545232 DOI: 10.1002/anie.202206390] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Indexed: 11/29/2022]
Abstract
Carbenes, including N-heterocyclic carbene (NHC) ligands, are used extensively to stabilize open-shell transition metal complexes and organic radicals. Yet, it remains unknown, which carbene stabilizes a radical well and, thus, how to design radical-stabilizing C-donor ligands. With the large variety of C-donor ligands experimentally investigated and their electronic properties established, we report herein their radical-stabilizing effect. We show that radical stabilization can be understood by a captodative frontier orbital description involving π-donation to- and π-donation from the carbenes. This picture sheds a new perspective on NHC chemistry, where π-donor effects usually are assumed to be negligible. Further, it allows for the intuitive prediction of the thermodynamic stability of covalent radicals of main group- and transition metal carbene complexes, and the quantification of redox non-innocence.
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Affiliation(s)
- Kevin Breitwieser
- Coordination ChemistrySaarland UniversityCampus C4.166123SaarbrückenGermany
| | - Hilke Bahmann
- Physical and Theoretical ChemistrySaarland UniversityCampus B2.266123SaarbrückenGermany
| | - Robert Weiss
- Organische ChemieFriedrich-Alexander-Universität (FAU) Erlangen-NürnbergHenkestr. 4291054ErlangenGermany
| | - Dominik Munz
- Coordination ChemistrySaarland UniversityCampus C4.166123SaarbrückenGermany
- Inorganic and General ChemistryFriedrich-Alexander-Universität (FAU) Erlangen-NürnbergEgerlandstr. 191058ErlangenGermany
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18
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Volk J, Heinz M, Leibold M, Bruhn C, Bens T, Sarkar B, Holthausen MC, Siemeling U. A crystalline cyclic (alkyl)(amino)carbene with a 1,1'-ferrocenylene backbone. Chem Commun (Camb) 2022; 58:10396-10399. [PMID: 36039867 DOI: 10.1039/d2cc03871d] [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
Cyclic (alkyl)(amino)carbenes with a 1,1'-ferrocenylene backbone (fcCAACs) are established as an original family by the preparation of a crystalline congener. The Ccarbene bond angle is unprecedentedly wide for a CAAC, causing an exceptionally pronounced ambiphilicity. The redox-active backbone opens the door to unconventional metalloradicals and oligoradicals.
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Affiliation(s)
- Julia Volk
- Institut für Chemie, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
| | - Myron Heinz
- Institut für Anorganische und Analytische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Michael Leibold
- 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.
| | - Tobias Bens
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 50659 Stuttgart, Germany
| | - Biprajit Sarkar
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 50659 Stuttgart, Germany
| | - Max C Holthausen
- Institut für Anorganische und Analytische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Ulrich Siemeling
- Institut für Chemie, Universität Kassel, Heinrich-Plett-Straße 40, 34132 Kassel, Germany.
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19
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Théry V, Molton F, Sirach S, Tillet N, Pécaut J, Tomás-Mendivil E, Martin D. The curious case of a sterically crowded Stenhouse salt. Chem Sci 2022; 13:9755-9760. [PMID: 36091895 PMCID: PMC9400627 DOI: 10.1039/d2sc01895k] [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: 04/01/2022] [Accepted: 07/27/2022] [Indexed: 11/23/2022] Open
Abstract
We report a peculiar Stenhouse salt. It does not evolve into cyclopentenones upon basification, due to the steric hindrance of its bulky stable carbene patterns. This allowed for the observation and characterization of the transient open-chain neutral derivative, which was isolated as its cyclized form. The latter features an unusually long reactive C-O bond (150 pm) and a rich electrochemistry, including oxidation into an air-persistent radical cation.
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Affiliation(s)
| | | | - Selim Sirach
- Univ. Grenoble Alpes, CNRS, DCM Grenoble 38000 France
| | - Neven Tillet
- Univ. Grenoble Alpes, CNRS, DCM Grenoble 38000 France
| | - Jacques Pécaut
- Univ. Grenoble Alpes, CEA, CNRS, INAC-SyMMES, UMR 5819 Grenoble 38000 France
| | | | - David Martin
- Univ. Grenoble Alpes, CNRS, DCM Grenoble 38000 France
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20
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Tendera L, Krummenacher I, Radius U. Cationic Nickel d9‐Metalloradicals [Ni(NHC)2]+. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Lukas Tendera
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Anorganische Chemie GERMANY
| | - Ivo Krummenacher
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Anorganische Chemie GERMANY
| | - Udo Radius
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Institut für Anorganische Chemie Am Hubland 97074 Würzburg GERMANY
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21
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Philipp MSM, Bertermann R, Radius U. N‐Heterocyclic Carbene and Cyclic (Alkyl)(amino)carbene Adducts of Germanium(IV) and Tin(IV) Chlorides and Organyl Chlorides. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Michael S. M. Philipp
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Inorganic Chemistry GERMANY
| | - Rüdiger Bertermann
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Inorganic Chemistry GERMANY
| | - Udo Radius
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Institut für Anorganische Chemie Am Hubland 97074 Würzburg GERMANY
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22
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Horrer G, Krummenacher I, Mann S, Braunschweig H, Radius U. N-Heterocyclic carbene and cyclic (alkyl)(amino)carbene complexes of vanadium(III) and vanadium(V). Dalton Trans 2022; 51:11054-11071. [PMID: 35796195 DOI: 10.1039/d2dt01250b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
[VCl3(THF)3] offers a convenient entrance point into the chemistry of carbene stabilized V(III) complexes. Herein we report the paramagnetic mono- and biscarbene complexes [VCl3(cAACMe)] 1, [VCl3(cAACMe)(THF)] 1(thf), [VCl3(IMes)] 2, [{VCl2(IiPrMe)(μ-Cl)}2] 3, [VCl3(IDipp)] 4, [VCl3(SIDipp)] 5, [VCl3(SIDipp)(THF)] 5(thf), [VCl3(ItBu)] 6, [VCl3(cAACMe)2] 7 and [VCl3(IiPrMe)2] 8. Reaction of 1 with MesMgCl, MesLi and LiNPh2 afforded the complexes [VCl2(Mes)(cAACMe)] 9, [cAACMeH]+[VCl2Mes2]-10 and [VCl2(NPh2)(cAACMe)] 11. The V(V) complexes [V(O)Cl3(IDipp)] 12 and [V(O)Cl3(SIDipp)] 13 were selectively prepared from oxygen oxidation of 4 and 5. [V(O)Cl3(IDipp)] 12 and [V(O)Cl3(IMes)] react with isocyanates to yield the NHC-ligated imido complexes [V(N-p-CH3C6H4)Cl3(IDipp)] 14, [V(N-p-FC6H4)Cl3(IDipp)] 15, [V(N-p-CH3C6H4)Cl3(SIDipp)] 16, [V(N-p-FC6H4)Cl3(SIDipp)] 17, [V(N-p-CH3C6H4)Cl3(IMes)] 18 and [V(N-p-FC6H4)Cl3(IMes)] 19.
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Affiliation(s)
- Günther Horrer
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Sophie Mann
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. .,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Udo Radius
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
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23
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Zhang J, Rahman M, Zhao Q, Feliciano J, Bisz E, Dziuk B, Lalancette R, Szostak R, Szostak M. N-Heterocyclic Carbene Complexes of Nickel(II) from Caffeine and Theophylline: Sustainable Alternative to Imidazol-2-ylidenes. Organometallics 2022; 41:1806-1815. [PMID: 36213557 PMCID: PMC9534456 DOI: 10.1021/acs.organomet.2c00019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Xanthines, such as caffeine and theophylline, are abundant natural products that are often present in foods. Leveraging renewable and benign resources for ligand design in organometallic chemistry and catalysis is one of the major missions of green and sustainable chemistry. In this Special Issue on Sustainable Organometallic Chemistry, we report the first nickel-N-heterocyclic carbene complexes derived from Xanthines. Well-defined, air- and moisture-stable, half-sandwich, cyclopentadienyl [CpNi(NHC)I] nickel-NHC complexes are prepared from the natural products caffeine and theophylline. The model complex has been characterized by x-ray crystallography. The evaluation of steric, electron-donating and π-accepting properties is presented. High activity in the model Suzuki-Miyaura cross-coupling is demonstrated. The data show that nickel-N-heterocyclic carbenes derived from both Earth abundant 3d transition metal and renewable natural products represent a sustainable alternative to the classical imidazol-2-ylidenes.
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Affiliation(s)
- Jin Zhang
- College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi'an 710021, China
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Jessica Feliciano
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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24
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Breitwieser K, Bahmann H, Weiss R, Munz D. Gauging Radical Stabilization with Carbenes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kevin Breitwieser
- Saarland University: Universitat des Saarlandes Coordination Chemistry GERMANY
| | - Hilke Bahmann
- Saarland University: Universitat des Saarlandes Theoretical Chemistry GERMANY
| | - Robert Weiss
- FAU Erlangen Nuremberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Organic Chemistry GERMANY
| | - Dominik Munz
- Universitat des Saarlandes Inorganic Chemistry: Coordination Chemistry Campus C 4.1 66123 Saarbrücken GERMANY
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25
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26
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Occhipinti G, Nascimento DL, Foscato M, Fogg DE, Jensen VR. The Janus face of high trans-effect carbenes in olefin metathesis: gateway to both productivity and decomposition. Chem Sci 2022; 13:5107-5117. [PMID: 35655574 PMCID: PMC9093171 DOI: 10.1039/d2sc00855f] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/19/2022] [Indexed: 11/25/2022] Open
Abstract
Ruthenium–cyclic(alkyl)(amino)carbene (CAAC) catalysts, used at ppm levels, can enable dramatically higher productivities in olefin metathesis than their N-heterocyclic carbene (NHC) predecessors. A key reason is the reduced susceptibility of the metallacyclobutane (MCB) intermediate to decomposition via β-H elimination. The factors responsible for promoting or inhibiting β-H elimination are explored via density functional theory (DFT) calculations, in metathesis of ethylene or styrene (a representative 1-olefin) by Ru–CAAC and Ru–NHC catalysts. Natural bond orbital analysis of the frontier orbitals confirms the greater strength of the orbital interactions for the CAAC species, and the consequent increase in the carbene trans influence and trans effect. The higher trans effect of the CAAC ligands inhibits β-H elimination by destabilizing the transition state (TS) for decomposition, in which an agostic MCB Cβ–H bond is positioned trans to the carbene. Unproductive cycling with ethylene is also curbed, because ethylene is trans to the carbene ligand in the square pyramidal TS for ethylene metathesis. In contrast, metathesis of styrene proceeds via a ‘late’ TS with approximately trigonal bipyramidal geometry, in which carbene trans effects are reduced. Importantly, however, the positive impact of a strong trans-effect ligand in limiting β-H elimination is offset by its potent accelerating effect on bimolecular coupling, a major competing means of catalyst decomposition. These two decomposition pathways, known for decades to limit productivity in olefin metathesis, are revealed as distinct, antinomic, responses to a single underlying phenomenon. Reconciling these opposing effects emerges as a clear priority for design of robust, high-performing catalysts. In ruthenium catalysts for olefin metathesis, carbene ligands of high trans influence/effect suppress decomposition via β-H elimination, but increase susceptibility to bimolecular decomposition.![]()
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Affiliation(s)
- Giovanni Occhipinti
- Department of Chemistry, University of Bergen Allégaten 41 N-5007 Bergen Norway
| | - Daniel L Nascimento
- Center for Catalysis Research & Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa Ottawa Canada K1N 6N5
| | - Marco Foscato
- Department of Chemistry, University of Bergen Allégaten 41 N-5007 Bergen Norway
| | - Deryn E Fogg
- Department of Chemistry, University of Bergen Allégaten 41 N-5007 Bergen Norway .,Center for Catalysis Research & Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa Ottawa Canada K1N 6N5
| | - Vidar R Jensen
- Department of Chemistry, University of Bergen Allégaten 41 N-5007 Bergen Norway
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27
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Radius U, Philipp MS. A Versatile Route To Cyclic (Alkyl)(Amino)Carbene‐stabilized Stibinidenes. Z Anorg Allg Chem 2022. [DOI: 10.1002/zaac.202200085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Udo Radius
- Universität Würzburg Institut für Anorganische Chemie Am Hubland 97074 Würzburg GERMANY
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28
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Jędrzkiewicz D, Mai J, Langer J, Mathe Z, Patel N, DeBeer S, Harder S. Access to a Labile Monomeric Magnesium Radical by Ball-Milling. Angew Chem Int Ed Engl 2022; 61:e202200511. [PMID: 35108440 PMCID: PMC9306460 DOI: 10.1002/anie.202200511] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Indexed: 12/13/2022]
Abstract
In order to isolate a monometallic Mg radical, the precursor (Am)MgI⋅(CAAC) (1) was prepared (Am=tBuC(N-DIPP)2 , DIPP=2,6-diisopropylphenyl, CAAC=cyclic (alkyl)(amino)carbene). Reduction of a solution of 1 in toluene with the reducing agent K/KI led to formation of a deep purple complex that rapidly decomposed. Ball-milling of 1 with K/KI gave the low-valent MgI complex (Am)Mg⋅(CAAC) (2) which after rapid extraction with pentane and crystallization was isolated in 15 % yield. Although a benzene solution of 2 decomposes rapidly to give Mg(Am)2 (3) and unidentified products, the radical is stable in the solid state. Its crystal structure shows planar trigonal coordination at Mg. The extremely short Mg-C distance of 2.056(2) Å indicates strong Mg-CAAC bonding. Calculations and EPR measurements show that most of the spin density is in a π* orbital located at the C-N bond in CAAC, leading to significant C-N bond elongation. This is supported by calculated NPA charges in 2: Mg +1.73, CAAC -0.82. Similar metal-to-CAAC charge transfer was calculated for M0 (CAAC)2 and [MI (CAAC)2 + ] (M=Be, Mg, Ca) complexes in which the metal charges range from +1.50 to +1.70. Although the spin density of the radical is mainly located at the CAAC ligand, complex 2 reacts as a low-valent MgI complex: reaction with a I2 solution in toluene gave (Am)MgI⋅(CAAC) (1) as the major product.
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Affiliation(s)
- Dawid Jędrzkiewicz
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Jonathan Mai
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Jens Langer
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Zachary Mathe
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645472Mülheim an der RuhrGermany
| | - Neha Patel
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645472Mülheim an der RuhrGermany
| | - Sjoerd Harder
- Inorganic and Organometallic ChemistryUniversität Erlangen-NürnbergEgerlandstrasse 191058ErlangenGermany
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Jędrzkiewicz D, Mai J, Langer J, Mathe Z, Patel N, DeBeer S, Harder S. Access to a Labile Monomeric Magnesium Radical by Ball‐Milling. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dawid Jędrzkiewicz
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Jonathan Mai
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Jens Langer
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Zachary Mathe
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45472 Mülheim an der Ruhr Germany
| | - Neha Patel
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45472 Mülheim an der Ruhr Germany
| | - Sjoerd Harder
- Inorganic and Organometallic Chemistry Universität Erlangen-Nürnberg Egerlandstrasse 1 91058 Erlangen Germany
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Vermersch F, Oliveira L, Hunter J, Soleilhavoup M, Jazzar R, Bertrand G. Cyclic (Alkyl)(amino)carbenes: Synthesis of Iminium Precursors and Structural Properties. J Org Chem 2022; 87:3511-3518. [PMID: 35133152 DOI: 10.1021/acs.joc.1c03075] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Using readily available preallylated aldehydes, we report a simple and divergent synthesis of cyclic (alkyl)(amino)carbene (CAAC) iminium precursors. Using a combination of crystallographic data and steric maps, we further elaborate on the specific steric properties of CAAC ligands with respect to state-of-the-art phosphine and carbene ligands.
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Affiliation(s)
- François Vermersch
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Luana Oliveira
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Joseph Hunter
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Michele Soleilhavoup
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Rodolphe Jazzar
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Guy Bertrand
- UCSD-CNRS Joint Research Laboratory (IRL 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
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31
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Termühlen S, Dutschke PD, Hepp A, Hahn E. Steric and Electronic Properties of Indol‐Derived CAAC Ligands. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202101065] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sebastian Termühlen
- Westfälische Wilhelms-Universität Münster: Westfalische Wilhelms-Universitat Munster Chemistry GERMANY
| | - Patrick D. Dutschke
- Westfälische Wilhelms-Universität Münster: Westfalische Wilhelms-Universitat Munster Chemistry GERMANY
| | - Alexander Hepp
- Westfälische Wilhelms-Universität Münster: Westfalische Wilhelms-Universitat Munster Chemistry GERMANY
| | - Ekkehardt Hahn
- Westfalische Wilhelms Universitat Munster Department of Chemistry Corrensstraße 30 48149 Münster GERMANY
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32
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Cyclic (alkyl)(amino)carbene (CAAC) ligands: Electronic structure and application as chemically- and redox-non-innocent ligands and chromophores. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2022. [DOI: 10.1016/bs.adomc.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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33
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Ghosh B, Cabrera-Trujillo JJ, Fernández I, Phukan AK. Stable N-heterocyclic borylenes with promising ligand properties: a contribution from theory. Inorg Chem Front 2022. [DOI: 10.1039/d2qi01511k] [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
DFT calculations reveal the power of ylides in stabilizing neutral singlet cyclic borylenes that are found to be capable of activating a variety of small molecules having enthalpically strong bonds.
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Affiliation(s)
- Bijoy Ghosh
- Department of Chemical Sciences, Tezpur University, Napam 784028, Assam, India
| | - Jorge Juan Cabrera-Trujillo
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040-Madrid, Spain
| | - Israel Fernández
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040-Madrid, Spain
| | - Ashwini K. Phukan
- Department of Chemical Sciences, Tezpur University, Napam 784028, Assam, India
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34
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Byun S, Park DA, Kim S, Kim S, Ryu JY, Lee J, Hong S. Highly selective ethenolysis with acyclic-aminooxycarbene ruthenium catalysts. Inorg Chem Front 2022. [DOI: 10.1039/d1qi01132d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Acyclic carbene–ruthenium catalysts were developed for the ethenolysis. Remarkable catalytic efficiency (turnover numbers of 100 000) and excellent α-olefin selectivity (up to 98%) were exhibited.
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Affiliation(s)
- Seunghwan Byun
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
- Grubbs Center for Polymers and Catalysis, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Da-Ae Park
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Seyong Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Sunghyun Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Ji Yeon Ryu
- Department of Chemistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
| | - Junseong Lee
- Department of Chemistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
| | - Sukwon Hong
- Department of Chemistry, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
- Grubbs Center for Polymers and Catalysis, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
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35
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Zhou L, Yao C, Ma W, Hu J, Wu Y, Zhang Z, Hu X. CO2 hydrogenation to formate catalyzed by highly stable and recyclable carbene-iridium under mild condition. J CO2 UTIL 2021. [DOI: 10.1016/j.jcou.2021.101769] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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36
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37
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Kaufmann S, Köppe R, Roesky PW. A square planar silylene nickel four-membered ring. Dalton Trans 2021; 50:14105-14109. [PMID: 34607336 DOI: 10.1039/d1dt02846d] [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
Herein the new nickel silylene [PhC(NtBu)2SiNi(C5Me5)]2, which features a square planar central ring motif consisting of two silicon and two nickel atoms is presented. The title compound was obtained by an insertion of the Ni(0) precursor [Ni(cod)2] (cod = 1,5-cyclooctadiene) in the Si-C bond of the silylene [PhC(NtBu)2Si(C5Me5)]. Analytic characterisation including mass spectrometry as well as IR and Raman spectroscopies was combined with quantum chemical calculations to get an insight on the bonding situation within the four-membered Si-Ni-ring.
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Affiliation(s)
- Sebastian Kaufmann
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131 Karlsruhe, Germany.
| | - Ralf Köppe
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131 Karlsruhe, Germany.
| | - Peter W Roesky
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131 Karlsruhe, Germany.
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38
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Philipp MSM, Krahfuss MJ, Radacki K, Radius U. N‐Heterocyclic Carbene and Cyclic (Alkyl)(amino)carbene Adducts of Antimony(III). Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100632] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Michael S. M. Philipp
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Mirjam J. Krahfuss
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Krzysztof Radacki
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Udo Radius
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
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39
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Gao Y, Yazdani S, Kendrick A, Junor GP, Kang T, Grotjahn DB, Bertrand G, Jazzar R, Engle KM. Cyclic (Alkyl)(amino)carbene Ligands Enable Cu‐Catalyzed Markovnikov Protoboration and Protosilylation of Terminal Alkynes: A Versatile Portal to Functionalized Alkenes**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Yang Gao
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
| | - Sima Yazdani
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
- Department of Chemistry and Biochemistry San Diego State University 5500 Campanile Drive San Diego CA 92182-1030 USA
| | - Aaron Kendrick
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
| | - Glen P. Junor
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
| | - Taeho Kang
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
| | - Douglas B. Grotjahn
- Department of Chemistry and Biochemistry San Diego State University 5500 Campanile Drive San Diego CA 92182-1030 USA
| | - Guy Bertrand
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
| | - Rodolphe Jazzar
- Department of Chemistry and Biochemistry University of California, San Diego UCSD-CNRS Joint Research Laboratory (IRL 3555) La Jolla CA 92093-0358 USA
| | - Keary M. Engle
- Department of Chemistry The Scripps Research Institute 10550 N Torrey Pines Road La Jolla CA 92037-1000 USA
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40
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Francisco MAS, Fantuzzi F, Cardozo TM, Esteves PM, Engels B, Oliveira RR. Taming the Antiferromagnetic Beast: Computational Design of Ultrashort Mn-Mn Bonds Stabilized by N-Heterocyclic Carbenes. Chemistry 2021; 27:12126-12136. [PMID: 34114702 PMCID: PMC8456913 DOI: 10.1002/chem.202101116] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Indexed: 12/26/2022]
Abstract
The development of complexes featuring low-valent, multiply bonded metal centers is an exciting field with several potential applications. In this work, we describe the design principles and extensive computational investigation of new organometallic platforms featuring the elusive manganese-manganese bond stabilized by experimentally realized N-heterocyclic carbenes (NHCs). By using DFT computations benchmarked against multireference calculations, as well as MO- and VB-based bonding analyses, we could disentangle the various electronic and structural effects contributing to the thermodynamic and kinetic stability, as well as the experimental feasibility, of the systems. In particular, we explored the nature of the metal-carbene interaction and the role of the ancillary η6 coordination to the generation of Mn2 systems featuring ultrashort metal-metal bonds, closed-shell singlet multiplicities, and positive adiabatic singlet-triplet gaps. Our analysis identifies two distinct classes of viable synthetic targets, whose electrostructural properties are thoroughly investigated.
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Affiliation(s)
- Marcos A. S. Francisco
- Instituto de QuímicaUniversidade Federal do Rio de JaneiroAv. Athos da Silveira Ramos 14921941909Rio de JaneiroBrazil
| | - Felipe Fantuzzi
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität WürzburgEmil-Fischer-Straße 4297074WürzburgGermany
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Thiago M. Cardozo
- Instituto de QuímicaUniversidade Federal do Rio de JaneiroAv. Athos da Silveira Ramos 14921941909Rio de JaneiroBrazil
| | - Pierre M. Esteves
- Instituto de QuímicaUniversidade Federal do Rio de JaneiroAv. Athos da Silveira Ramos 14921941909Rio de JaneiroBrazil
| | - Bernd Engels
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität WürzburgEmil-Fischer-Straße 4297074WürzburgGermany
| | - Ricardo R. Oliveira
- Instituto de QuímicaUniversidade Federal do Rio de JaneiroAv. Athos da Silveira Ramos 14921941909Rio de JaneiroBrazil
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41
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Dong Z, Blaskovits JT, Fadaei-Tirani F, Scopelliti R, Sienkiewicz A, Corminboeuf C, Severin K. Tuning the π-Accepting Properties of Mesoionic Carbenes: A Combined Computational and Experimental Study. Chemistry 2021; 27:11983-11988. [PMID: 34105837 PMCID: PMC8456875 DOI: 10.1002/chem.202101742] [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: 05/17/2021] [Indexed: 02/02/2023]
Abstract
Mesoionic imidazolylidenes are recognized as excellent electron‐donating ligands in organometallic and main group chemistry. However, these carbene ligands typically show poor π‐accepting properties. A computational analysis of 71 mesoionic imidazolylidenes that bear different aryl or heteroaryl substituents in C2 position was performed. The study has revealed that a diphenyltriazinyl (Dpt) substituent renders the corresponding carbene particularly π‐acidic. The computational results could be corroborated experimentally. A mesoionic imidazolylidene with a Dpt substituent was found to be a better σ‐donor and a better π‐acceptor compared to an Arduengo‐type N‐heterocyclic carbene. To demonstrate the utility of the new carbene, the ligand was used to stabilize a low‐valent paramagnetic tin compound.
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Affiliation(s)
- Zhaowen Dong
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - J Terence Blaskovits
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Andrzej Sienkiewicz
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.,ADSresonances Sarl, Route de Genève 60B, 1028, Préverenges, Switzerland
| | - Clémence Corminboeuf
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
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42
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Zhao Q, Meng G, Li G, Flach C, Mendelsohn R, Lalancette R, Szostak R, Szostak M. IPr# - highly hindered, broadly applicable N-heterocyclic carbenes. Chem Sci 2021; 12:10583-10589. [PMID: 34447551 PMCID: PMC8356752 DOI: 10.1039/d1sc02619d] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 06/28/2021] [Indexed: 12/15/2022] Open
Abstract
IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) represents the most important NHC (NHC = N-heterocyclic carbene) ligand throughout the field of homogeneous catalysis. Herein, we report the synthesis, catalytic activity, and full structural and electronic characterization of novel, sterically-bulky, easily-accessible NHC ligands based on the hash peralkylation concept, including IPr#, Np# and BIAN-IPr#. The new ligands have been commercialized in collaboration with Millipore Sigma: IPr#HCl, 915653; Np#HCl; 915912; BIAN-IPr#HCl, 916420, enabling broad access of the academic and industrial researchers to new ligands for reaction optimization and screening. In particular, the synthesis of IPr# hinges upon cost-effective, modular alkylation of aniline, an industrial chemical that is available in bulk. The generality of this approach in ligand design is demonstrated through facile synthesis of BIAN-IPr# and Np#, two ligands that differ in steric properties and N-wingtip arrangement. The broad activity in various cross-coupling reactions in an array of N–C, O–C, C–Cl, C–Br, C–S and C–H bond cross-couplings is demonstrated. The evaluation of steric, electron-donating and π-accepting properties as well as coordination chemistry to Au(i), Rh(i) and Pd(ii) is presented. Given the tremendous importance of NHC ligands in homogenous catalysis, we expect that this new class of NHCs will find rapid and widespread application. We report novel, sterically-bulky, easily-accessible NHC ligands based on the hash peralkylation concept. The new ligands have been commercialized in collaboration with Millipore Sigma: IPr#HCl, 915653; Np#HCl; 915912; BIAN-IPr#HCl, 916420.![]()
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Affiliation(s)
- Qun Zhao
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Guangrong Meng
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Guangchen Li
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Carol Flach
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Richard Mendelsohn
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Roger Lalancette
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University F. Joliot-Curie 14 Wroclaw 50-383 Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University 73 Warren Street Newark NJ 07102 USA
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43
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Gao Y, Yazdani S, Kendrick A, Junor GP, Kang T, Grotjahn DB, Bertrand G, Jazzar R, Engle KM. Cyclic (Alkyl)(amino)carbene Ligands Enable Cu-Catalyzed Markovnikov Protoboration and Protosilylation of Terminal Alkynes: A Versatile Portal to Functionalized Alkenes*. Angew Chem Int Ed Engl 2021; 60:19871-19878. [PMID: 34159696 DOI: 10.1002/anie.202106107] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/11/2021] [Indexed: 12/19/2022]
Abstract
Regioselective hydrofunctionalization of alkynes represents a straightforward route to access alkenyl boronate and silane building blocks. In previously reported catalytic systems, high selectivity is achieved with a limited scope of substrates and/or reagents, with general solutions lacking. Herein, we describe a selective copper-catalyzed Markovnikov hydrofunctionalization of terminal alkynes that is facilitated by strongly donating cyclic (alkyl)(amino)carbene (CAAC) ligands. Using this method, both alkyl- and aryl-substituted alkynes are coupled with a variety of boryl and silyl reagents with high α-selectivity. The reaction is scalable, and the products are versatile intermediates that can participate in various downstream transformations. Preliminary mechanistic experiments shed light on the role of CAAC ligands in this process.
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Affiliation(s)
- Yang Gao
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
| | - Sima Yazdani
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA.,Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA
| | - Aaron Kendrick
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
| | - Glen P Junor
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA
| | - Taeho Kang
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
| | - Douglas B Grotjahn
- Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-1030, USA
| | - Guy Bertrand
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA
| | - Rodolphe Jazzar
- Department of Chemistry and Biochemistry, University of California, San Diego, UCSD-CNRS Joint Research Laboratory (IRL 3555), La Jolla, CA, 92093-0358, USA
| | - Keary M Engle
- Department of Chemistry, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA, 92037-1000, USA
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44
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Nascimento D, Foscato M, Occhipinti G, Jensen VR, Fogg DE. Bimolecular Coupling in Olefin Metathesis: Correlating Structure and Decomposition for Leading and Emerging Ruthenium-Carbene Catalysts. J Am Chem Soc 2021; 143:11072-11079. [PMID: 34270895 PMCID: PMC8397316 DOI: 10.1021/jacs.1c04424] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Indexed: 12/19/2022]
Abstract
Bimolecular catalyst decomposition is a fundamental, long-standing challenge in olefin metathesis. Emerging ruthenium-cyclic(alkyl)(amino)carbene (CAAC) catalysts, which enable breakthrough advances in productivity and general robustness, are now known to be extraordinarily susceptible to this pathway. The details of the process, however, have hitherto been obscure. The present study provides the first detailed mechanistic insights into the steric and electronic factors that govern bimolecular decomposition. Described is a combined experimental and theoretical study that probes decomposition of the key active species, RuCl2(L)(py)(═CH2) 1 (in which L is the N-heterocyclic carbene (NHC) H2IMes, or a CAAC ligand: the latter vary in the NAr group (NMes, N-2,6-Et2C6H3, or N-2-Me,6-iPrC6H3) and the substituents on the quaternary site flanking the carbene carbon (i.e., CMe2 or CMePh)). The transiently stabilized pyridine adducts 1 were isolated by cryogenic synthesis of the metallacyclobutanes, addition of pyridine, and precipitation. All are shown to decompose via second-order kinetics at -10 °C. The most vulnerable CAAC species, however, decompose more than 1000-fold faster than the H2IMes analogue. Computational studies reveal that the key factor underlying accelerated decomposition of the CAAC derivatives is their stronger trans influence, which weakens the Ru-py bond and increases the transient concentration of the 14-electron methylidene species, RuCl2(L)(═CH2) 2. Fast catalyst initiation, a major design goal in olefin metathesis, thus has the negative consequence of accelerating decomposition. Inhibiting bimolecular decomposition offers major opportunities to transform catalyst productivity and utility, and to realize the outstanding promise of olefin metathesis.
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Affiliation(s)
- Daniel
L. Nascimento
- Center
for Catalysis Research & Innovation, and Department of Chemistry
and Biomolecular Sciences, University of
Ottawa, Ottawa, Canada K1N 6N5
| | - Marco Foscato
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Giovanni Occhipinti
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Vidar R. Jensen
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
| | - Deryn E. Fogg
- Center
for Catalysis Research & Innovation, and Department of Chemistry
and Biomolecular Sciences, University of
Ottawa, Ottawa, Canada K1N 6N5
- Department
of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway
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45
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Collado A, Nelson DJ, Nolan SP. Optimizing Catalyst and Reaction Conditions in Gold(I) Catalysis-Ligand Development. Chem Rev 2021; 121:8559-8612. [PMID: 34259505 DOI: 10.1021/acs.chemrev.0c01320] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This review considers phosphine and N-heterocyclic carbene complexes of gold(I) that are used as (pre)catalysts for a range of reactions in organic synthesis. These are divided according to the structure of the ligand, with the narrative focusing on studies that offer a quantitative comparison between the ligands and readily available or widely used existing systems.
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Affiliation(s)
- Alba Collado
- Departamento de Química Inorgánica, Universidad Autónoma de Madrid, C/Francisco Tomás y Valiente, 7, 28049 Madrid, Spain
| | - David J Nelson
- WestCHEM Department of Pure & Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, Scotland
| | - Steven P Nolan
- Department of Chemistry and Center for Sustainable Chemistry, Ghent University, Krijgslaan 281 - S3, 9000 Gent, Belgium
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46
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Romine AM, Demer MJ, Gembicky M, Rheingold AL, Engle KM. Ligand Rearrangement Leads to Tetrahydrothiophene-Functionalized N,S-Heterocyclic Carbene Palladium(II) Complexes. Organometallics 2021; 40:2311-2319. [PMID: 34433997 DOI: 10.1021/acs.organomet.1c00041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tetrahydrothiophene-functionalized N,S-heterocyclic carbene palladium(II) complexes are synthesized through an unexpected rearrangement that proceeds with palladium(II) trifluoroacetate and not with palladium(II) acetate, palladium(II) bromide, or palladium(II) chloride. A series of these complexes were isolated and characterized by X-ray crystallography. The mechanism of formation of these [3.2.1]-palladabicycles was explored, and the catalytic capabilities of these complexes were demonstrated in representative C-C coupling reactions.
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Affiliation(s)
- Andrew M Romine
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Matthew J Demer
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Milan Gembicky
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093, United States
| | - Arnold L Rheingold
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093, United States
| | - Keary M Engle
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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47
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Zhou L, Zhang D, Hu J, Wu Y, Geng J, Hu X. Thermal Dehydrogenation and Hydrolysis of BH3NH3 Catalyzed by Cyclic (Alkyl)(amino)carbene Iridium Complexes under Mild Conditions. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00302] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Lei Zhou
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Dejin Zhang
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Jinling Hu
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Youting Wu
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Jiao Geng
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Xingbang Hu
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
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48
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Gorantla SMNVT, Parameswaran P, Mondal KC. Stabilization of group 14 elements E = C, Si, Ge by hetero-bileptic ligands cAAC, MCO n with push-pull mechanism. J Comput Chem 2021; 42:1159-1177. [PMID: 33856693 DOI: 10.1002/jcc.26530] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/19/2021] [Accepted: 03/09/2021] [Indexed: 11/05/2022]
Abstract
The stability and bonding of a series of hetero-diatomic molecules with general formula (cAAC)EM(CO)n , where cAAC = cyclic alkyl(amino) carbene; E = group 14 elements (C, Si, and Ge); M = transition metal (Ni, Fe, and Cr) have been studied by quantum chemical calculations using density functional theory (DFT) and energy decomposition analysis-natural orbital chemical valence (EDA-NOCV). The equilibrium geometries were calculated at the BP86/def2-TZVPP level of theory. The tri-coordinated group 14 complex (1a, 4a, and 7a) in which one of the CO groups is migrated to the central group 14 element from adjacent metal is theoretically found to be more stable when the central atom (E) is carbon. On the other hand, the two-coordinate group 14 element containing metal-complexes (2, 5, 8, 3, 6, and 9) are found to be more stable with their corresponding heavier analogues. The electronic structures of all the molecules have been analyzed by molecular orbital, topological analysis of electron density and natural bond orbital (NBO) analysis at the M06/def2-TZVPP//BP86/def2-TZVPP level of theory. The nature of the cAACE and EM bonds has been studied by EDA-NOCV calculations at BP86-D3(BJ)/TZ2P level of theory. The EDA analysis suggests that the bonding of cAACC(CO) can be best represented by electron sharing σ and π interactions, whereas, C(CO)M(CO)n-1 by dative σ and π interactions. On the other hand, EDA-NOCV calculations suggests both dative σ and π interactions for cAACE and EM(CO)n bonds of the corresponding Si and Ge analogues having stronger σ- and relatively weaker π-bonds. The topological analysis of electron density supports the closed-shell interaction for the Si and Ge complexes and open-shell interaction for the carbon complexes. The calculated proton affinity and hydride affinity values corroborated well with the present bonding description. This class of complexes might act as efficient future catalysts for different organic transformations due to the presence of electron rich group 14 element and metal carbonyl.
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49
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Rajendran NM, Gautam N, Sarkar P, Ahmed J, Das A, Das S, Pati SK, Mandal SK. Bicyclic (alkyl)(amino)carbene stabilized zinc(0) complex with singlet biradicaloid ground state. Chem Commun (Camb) 2021; 57:5282-5285. [PMID: 33942839 DOI: 10.1039/d1cc01298c] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A storable bicyclic (alkyl)(amino)carbene (BICAAC) stabilized two coordinate zinc(0) complex [(BICAAC)2Zn] (2) was synthesized. DFT calculations reveal that BICAAC plays a decisive role in imparting the stability to 2. This complex activates the C(sp3)-Cl bond of trityl chloride generating the Gomberg's free radical with greater efficiency than metallic Zn powder.
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Affiliation(s)
- N M Rajendran
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
| | - Nimisha Gautam
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
| | - Pallavi Sarkar
- Theoretical Sciences Unit, Jawaharlal Nehru Centre For Advanced Scientific Research, Bangalore 560064, India.
| | - Jasimuddin Ahmed
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
| | - Arpan Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
| | - Shubhajit Das
- Theoretical Sciences Unit, Jawaharlal Nehru Centre For Advanced Scientific Research, Bangalore 560064, India.
| | - Swapan K Pati
- Theoretical Sciences Unit, Jawaharlal Nehru Centre For Advanced Scientific Research, Bangalore 560064, India.
| | - Swadhin K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
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50
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Föhrenbacher SA, Zeh V, Krahfuss MJ, Ignat'ev NV, Finze M, Radius U. Tris(pentafluoroethyl)difluorophosphorane and
N
‐Heterocyclic Carbenes: Adduct Formation and Frustrated
Lewis
Pair Reactivity. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100183] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Steffen A. Föhrenbacher
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Vivien Zeh
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Mirjam J. Krahfuss
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Nikolai V. Ignat'ev
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Consultant Merck KGaA Frankfurter Straße 250 64293 Darmstadt Germany
| | - Maik Finze
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Udo Radius
- Institute of Inorganic Chemistry Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
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