1
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Patra J, Nair AM, Volla CMR. Expedient radical phosphonylations via ligand to metal charge transfer on bismuth. Chem Sci 2024; 15:7136-7143. [PMID: 38756813 PMCID: PMC11095378 DOI: 10.1039/d4sc00692e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 04/08/2024] [Indexed: 05/18/2024] Open
Abstract
Bismuth, in spite of its low cost and low toxicity, has found limited application in organic synthesis. Although the photoactivity of Bi(iii) salts has been well studied, this has not been effectively exploited in photocatalysis. To date, only a single report exists for the Bi-based photocatalysis, wherein carbon centered radicals were generated using ligand to metal charge transfer (LMCT) on bismuth. In this regard, expanding the horizon of bismuth LMCT catalysis for the generation of heteroatom centered radicals, we hereby report an efficient radical phosphonylation using BiCl3 as the LMCT catalyst. Phosphonyl radicals generated via visible-light induced LMCT of BiCl3 were subjected to a variety of transformations like alkylation, amination, alkynylation and cascade cyclizations. The catalytic system tolerated a wide range of substrate classes, delivering excellent yields of the scaffolds. The reactions were scalable and required low catalytic loading of bismuth. Detailed mechanistic studies were carried out to probe the reaction mechanism. Diverse radical phosphonylations leading to the formation of sp3-C-P, sp2-C-P, sp-C-P, and P-N bonds in the current work present the candidacy of bismuth as a versatile photocatalyst for small molecule activation.
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Affiliation(s)
- Jatin Patra
- Department of Chemistry, Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Akshay M Nair
- Department of Chemistry, Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Chandra M R Volla
- Department of Chemistry, Indian Institute of Technology Bombay Powai Mumbai 400076 India
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2
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Park M, Schmidt C, Türck S, Hanusch F, Hirmer SV, Ott I, Casini A, Inoue S. Potent Anticancer Activity of a Dinuclear Gold(I) bis-N-Heterocyclic Imine Complex Related to Thioredoxin Reductase Inhibition in Vitro. Chempluschem 2024; 89:e202300557. [PMID: 37937471 DOI: 10.1002/cplu.202300557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/09/2023]
Abstract
A dinuclear gold(I) complex featuring a strongly donating bis-N-heterocyclic imine ligand was synthesised and characterised by different methods, including single crystal X-ray diffraction (SC-XRD) analysis. The compound has been tested for its antiproliferative effects in a panel of human cancer cell lines in vitro, showing highly selective anticancer effects, particularly against human A549 non-small cell lung cancer cells (NSCLC), with respect to non-tumorigenic cells (VERO). The accumulation of the compound in A549 and VERO cells was studied by high-resolution continuum source atomic absorption spectrometry (HRCS-AAS), revealing that the anticancer effects are not particularly related to the different amounts of gold taken up by the cells over 72 h. Enzyme inhibition studies to evaluate the activity of the seleno-enzyme thioredoxin reductase (TrxR) in cancer cell extracts show that the gold(I) compound is a potent inhibitor (IC50=0.567±0.208 μM), while the free ligand is ineffective. This result correlates with the observed compound's selectivity towards A549 cells overexpressing the enzyme.
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Affiliation(s)
- Mihyun Park
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching b. München, Germany
| | - Claudia Schmidt
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching b. München, Germany
| | - Sebastian Türck
- Institute of Medicinal and Pharmaceutical Chemistry, Technische Universität Braunschweig, Beethovenstr. 55, 38106, Braunschweig, Germany
| | - Franziska Hanusch
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching b. München, Germany
| | - Simone V Hirmer
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching b. München, Germany
| | - Ingo Ott
- Institute of Medicinal and Pharmaceutical Chemistry, Technische Universität Braunschweig, Beethovenstr. 55, 38106, Braunschweig, Germany
| | - Angela Casini
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching b. München, Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching b. München, Germany
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3
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LaPierre EA, Patrick BO, Manners I. Synthesis of Carbene-Stabilized PNPN Fragments and Their Carbene-Dependent Redox Properties. J Am Chem Soc 2024; 146:6326-6335. [PMID: 38408316 DOI: 10.1021/jacs.4c00148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Herein, we report the synthesis of carbene-stabilized 1,3-diaza-2,4-diphosphabutenes CAACMePNPNCAACMe 4CAAC (CAACMe = 1-[2,6-bis(isopropyl)phenyl]-3,3,5,5-tetramethyl-2-pyrrolidinylidene) and IPrPNPNIPr 4NHC (IPr = 1,3-Bis(2,6-diisopropylphenyl)-imidazol-2-ylidene). The bonding in both systems is defined by a delocalized polar covalent π-system, with 4NHC exhibiting increased conjugation relative to 4CAAC. The nature of the stabilizing carbene also influences the redox properties of the compound, with 4CAAC undergoing potassium-mediated reduction to the closed-shell P-P bonded dimer K252, which upon treatment with Kryptofix-2,2,2 converts to the transient radical anion [Kcrypt][5], the formal one-electron reduction product of 4CAAC. In contrast, 4NHC undergoes reversible one-electron oxidation to the stable radical cation [6NHC][SbF6]. Computational and spectroscopic analyses of both radical species are suggestive of unevenly delocalized spin, with the bulk of the spin density residing on phosphorus in both cases.
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Affiliation(s)
- Etienne A LaPierre
- Department of Chemistry, University of Victoria, 3800 Finnerty Rd, Victoria, British Columbia V8P 5C2, Canada
| | - Brian O Patrick
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Ian Manners
- Department of Chemistry, University of Victoria, 3800 Finnerty Rd, Victoria, British Columbia V8P 5C2, Canada
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4
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Groll L, Kelly JA, Inoue S. Reactivity of NHI-Stabilized Heavier Tetrylenes towards CO 2 and N 2 O. Chem Asian J 2024; 19:e202300941. [PMID: 37996985 DOI: 10.1002/asia.202300941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/22/2023] [Accepted: 11/23/2023] [Indexed: 11/25/2023]
Abstract
A heteroleptic amino(imino)stannylene (TMS2 N)(It BuN)Sn: (TMS=trimethylsilyl, It Bu=C[(N-t Bu)CH]2 ) as well as two homoleptic NHI-stabilized tetrylenes, (It BuN)2 E: (NHI=N-heterocyclic imine, E=Ge, Sn) are presented. VT-NMR investigations of (It BuN)2 Sn: (2) reveal an equilibrium between the monomeric stannylene at room temperature and the dimeric form at -80 °C as well as in the solid state. Upon reaction of the homoleptic tetrylenes with CO2 , both compounds insert two equivalents of CO2 , however differing bonding modes can be observed. (It BuN)2 Sn: (2) inserts one equivalent of CO2 into each Sn-N bond, giving carbamato groups coordinated κ2 O,O' to the metal center. With (It BuN)2 Ge: (3), the Ge-N bonds stay intact upon activation, being bridged by one molecule of CO2 respectively, forming 4-membered rings. Furthermore, the reactivity of 2 towards N2 O was investigated, resulting in partial oxidation to form stannylene dimer [((It BuN)3 SnO)(It BuN)Sn:]2 (6).
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Affiliation(s)
- Lisa Groll
- TUM School of Natural Sciences, Department of Chemistry, Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany
| | - John A Kelly
- TUM School of Natural Sciences, Department of Chemistry, Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany
| | - Shigeyoshi Inoue
- TUM School of Natural Sciences, Department of Chemistry, Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany
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5
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Vasanthakumar A, Price JS, Emslie DJH. Rare earth dialkyl cations and monoalkyl dications supported by a rigid neutral pincer ligand: synthesis and ethylene polymerization. Chem Sci 2023; 14:8514-8523. [PMID: 37592999 PMCID: PMC10430518 DOI: 10.1039/d3sc01830j] [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: 04/10/2023] [Accepted: 07/15/2023] [Indexed: 08/19/2023] Open
Abstract
A palladium-catalyzed coupling reaction between 4,5-dibromo-2,7-di-tert-butyl-9,9-dimethylxanthene and 2 equiv. of 1,3-diisopropylimidazolin-2-imine afforded the rigid neutral 2,7-di-tert-butyl-4,5-bis(1,3-diisopropylimidazolin-2-imino)-9,9-dimethylxanthene (XII2) pincer ligand. Reaction of XII2 with YCl3(THF)3.5 provided [(XII2)YCl3] (1). However, compound 1 failed to react cleanly with 3 equiv. of LiCH2SiMe3, and the reaction of XII2 with [Y(CH2SiMe3)3(THF)2] afforded a complex mixture of products. To access group 3 alkyl complexes without the intermediacy of [(XII2)M(CH2SiMe3)3], the XII2 ligand was protonated using [H(OEt2)2][B(C6F5)4] to form [H(XII2)][B(C6F5)4], and subsequent reaction with [M(CH2SiMe3)3(THF)2] (M = Y, Sc) directly afforded the cationic scandium and yttrium dialkyl complexes [(XII2)M(CH2SiMe3)2][B(C6F5)4] {M = Y (2) and Sc (3)}. Reaction of 3 with B(C6F5)3 in C6D5Br afforded dicationic [(XII2)Sc(CH2SiMe2CH2SiMe3)][MeB(C6F5)3][B(C6F5)4] (4) featuring a CH2SiMe2CH2SiMe3 ligand, formed as a result of methyl anion abstraction from silicon, with concomitant migration of the neighbouring CH2SiMe3 group from scandium to silicon. The MeB(C6F5)3 anion in 4 forms a contact ion pair. By contrast, reaction of 1 with [CPh3][B(C6F5)3] in C6D5Br/toluene or o-C6H4F2/toluene afforded dicationic [(XII2)Sc(CH2SiMe3)(ηx-toluene)n][B(C6F5)4]2 (5). Compounds 2-4 showed negligible ethylene polymerization activity, whereas 5 is highly active (up to 870 kg mol-1 h-1 atm-1 in o-C6H4F2/toluene under 1 atm of ethylene at room temperature).
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Affiliation(s)
- Aathith Vasanthakumar
- Department of Chemistry, McMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - Jeffrey S Price
- Department of Chemistry, McMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - David J H Emslie
- Department of Chemistry, McMaster University 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
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6
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Krishnapriya VU, Suresh CH. Imidazolin-2-imine and Imidazolin-2-methylidene Substitutions to Benzene, Pyridine, Phosphine, and N-Heterocyclic Carbene Predict Highly Electron-rich Ligands. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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7
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Approaching the uniaxiality of magnetic anisotropy in single-molecule magnets. Sci China Chem 2023. [DOI: 10.1007/s11426-022-1423-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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8
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Thomas-Hargreaves LR, Liu YQ, Cui ZH, Pan S, Buchner MR. Bonding situations in tricoordinated beryllium phenyl complexes. J Comput Chem 2023; 44:397-405. [PMID: 35767185 DOI: 10.1002/jcc.26950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/01/2022] [Accepted: 06/03/2022] [Indexed: 12/31/2022]
Abstract
The bonding situation in the tricoordinated beryllium phenyl complexes [BePh3 ]- , [(pyridine)BePh2 ] and [(trimethylsilyl-N-heterocyclic imine)BePh2 ] is investigated experimentally and computationally. Comparison of the NMR spectroscopic properties of these complexes and of their structural parameters, which were determined by single crystal X-ray diffraction experiments, indicates the presence of π-interactions. Topology analysis of the electron density reveals elliptical electron density distributions at the bond critical points and the double bond character of the beryllium-element bonds is verified by energy decomposition analysis with the combination of natural orbital for chemical valence. The present beryllium-element bonds are highly polarized and the ligands around the central atom have a strong influence on the degree of π-delocalization. These results are compared to related triarylboranes.
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Affiliation(s)
| | - Yu-Qian Liu
- Institute of Atomic and Molecular Physics, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Jilin University, Changchun
| | - Zhong-Hua Cui
- Institute of Atomic and Molecular Physics, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Jilin University, Changchun
| | - Sudip Pan
- Fachbereich Chemie, Philipps-Universität Marburg, Marburg, Germany.,Institute of Atomic and Molecular Physics, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Jilin University, Changchun
| | - Magnus R Buchner
- Fachbereich Chemie, Philipps-Universität Marburg, Marburg, Germany
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9
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Wang N, Feng B, Cui P, Tamm M, Chen Y. Imidazolin-2-iminato Cerium(IV) Chlorides: Synthesis, Structure and Electrochemical Properties. Chem Asian J 2023; 18:e202201135. [PMID: 36445801 DOI: 10.1002/asia.202201135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/27/2022] [Accepted: 11/28/2022] [Indexed: 11/30/2022]
Abstract
The ligand field greatly affects the redox properties of cerium. Herein, cerium(III) and cerium(IV) complexes supported by imidazolin-2-iminato ligands were synthesized and structurally characterized, and their electrochemical properties were investigated. Silylamine elimination of cerium(III) amide Ce{N(SiMe3 )2 }3 with imidazolin-2-imine ImR NH (R=Mes, tBu, iPr) provided imidazolin-2-iminato cerium(III) complexes, [(ImMes N)(ImMes NH)Ce{N(SiMe3 )2 }2 ] (1), [(ImtBu N)2 (ImtBu NH)Ce{N(SiMe3 )2 }] (2) and [(ImiPr N)2 (ImiPr NH)Ce(μ-ImiPr N)]2 (4) in 71-85% yields. These cerium(III) complexes were successfully oxidized by Ph3 CCl or C2 Cl6 to afford imidazolin-2-iminato cerium(IV) chlorides, [(ImMes N)2 Ce{N(SiMe3 )2 }Cl] (5), [(ImtBu N)3 CeCl] (6) and [(ImiPr N)2 Ce(μ-ImiPr N)Cl]2 (7) in 70%-76% yields. All complexes were characterized by the single-crystal X-ray diffraction, which showed that 1, 2, 5 and 6 are monomers while 4 and 7 are dimers. The electrochemical studies indicated that the Ce(III/IV) couples for 5 and 6 are more negative than those of silylamido cerium(IV) complexes, and the Ce(III/IV) couples for 1 and 2 have a similar trend.
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Affiliation(s)
- Ning Wang
- Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, P. R. China.,State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Bin Feng
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Peng Cui
- Key Laboratory of Functional Molecular Solids Ministry of Education Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials ScienceAnhui Normal University, S189 Jiuhua Road, Wuhu, Anhui, 241002, P. R. China
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China.,Spin-X Institute School of Chemistry and Chemical Engineering Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, South China University of Technology, Guangzhou, 510641, P. R. China
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10
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Das A, Sarkar P, Maji S, Pati SK, Mandal SK. Mesoionic N-Heterocyclic Imines as Super Nucleophiles in Catalytic Couplings of Amides with CO 2. Angew Chem Int Ed Engl 2022; 61:e202213614. [PMID: 36259383 DOI: 10.1002/anie.202213614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Indexed: 11/07/2022]
Abstract
An extended class of stable mesoionic N-heterocyclic imines (mNHIs), containing a highly polarized exocyclic imine moiety, were synthesized. The calculated proton affinities (PA) and experimentally determined Tolman electronic parameters (TEPs) reveal that these synthesized mNHIs have the highest basicity and donor ability among NHIs reported so far. The superior nucleophilicity of newly designed mNHIs was utilized in devising a strategy to incorporate CO2 as a bridging unit under reductive conditions to couple inert primary amides. This strategy was further extended to hetero-couplings between amide and amine using CO2 . These hitherto unknown catalytic transformations were introduced in the diversification of various biologically active drug molecules under metal-free conditions. The underlying mechanism was explored by performing a series of control experiments, characterizing key intermediates using spectroscopic and crystallographic techniques.
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Affiliation(s)
- Arpan Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, Nadia, India
| | - Pallavi Sarkar
- Department Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, 560064, India
| | - Subir Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, Nadia, India
| | - Swapan K Pati
- Department Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, 560064, India
| | - Swadhin K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, Nadia, India
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11
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Synthesis, structural characterization and catalytic application of zinc and cadmium sulfur complexes with imidazol-2-ylidene-N’-phenylthiourea ligand scaffold. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.116055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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12
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Sarkar D, Groll L, Munz D, Hanusch F, Inoue S. Ligand Assisted CO2 Sequestration and Catalytic Valorization by an NHI‐Stabilized Stannylene. ChemCatChem 2022. [DOI: 10.1002/cctc.202201048] [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)
- Debotra Sarkar
- Technical University of Munich: Technische Universitat Munchen Department of Chemistry GERMANY
| | - Lisa Groll
- Technical University Munich: Technische Universitat Munchen Department of Chemistry GERMANY
| | - Dominik Munz
- Saarland University - Campus Saarbrucken: Universitat des Saarlandes Inorganic Chemistry GERMANY
| | - Franziska Hanusch
- Technical University of Munich: Technische Universitat Munchen Department of Chemistry GERMANY
| | - Shigeyoshi Inoue
- Technische Universität München Fakultät für Chemie Lichtenbergstraße 485748 Garching 85748 Garching bei München GERMANY
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13
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Koneczny M, Erol AB, Mauduit M, Eisen MS, Tamm M. Titanium complexes with unsymmetrically substituted imidazolin-2-iminato ligands. Dalton Trans 2022; 51:11448-11456. [PMID: 35822511 DOI: 10.1039/d2dt01740g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of the unsymmetrical N-heterocyclic carbenes 1-(2,4,6-trimethylphenyl)-3-(adamantyl)imidazolin-2-ylidene (IAdMes, 1a) and 1-(2,6-diisopropylphenyl)-3-(adamantyl)imidazolin-2-ylidene (IAdDipp, 1b) with trimethylsilyl azide furnished the 2-(trimethylsilylimino)imidazolines 2a (ImAdMesNSiMe3) and 2b (ImAdDippNSiMe3). Desilylation by stirring in methanol gave the corresponding imidazolin-2-imines 3a (ImAdMesNH) and 3b (ImAdDippNH). 2a and 2b were treated with [TiCl4(THF)2] (THF = tetrahydrofuran) and [CpTiCl3] (Cp = η5-C5H5) to form the mono- and bis(imidazolin-2-iminato) titanium(IV) complexes [(ImAdRN)TiCl3] (4, R = Mes, Dipp), [Cp(ImAdRN)TiCl2] (5, R = Mes, Dipp), and [(ImAdRN)2TiCl2] (6, R = Mes, Dipp). The crystal structures of all compounds except 2b were determined by X-ray diffraction analysis.
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Affiliation(s)
- Marvin Koneczny
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany.
| | - Arife Büsra Erol
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany.
| | - Marc Mauduit
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France
| | - Moris S Eisen
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, 32000 Haifa, Israel
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany.
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14
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Rudolf R, Neuman NI, Walter RRM, Ringenberg MR, Sarkar B. Mesoionic Imines (MIIs): Strong Donors and Versatile Ligands for Transition Metals and Main Group Substrates. Angew Chem Int Ed Engl 2022; 61:e202200653. [PMID: 35286004 PMCID: PMC9322014 DOI: 10.1002/anie.202200653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Indexed: 11/08/2022]
Abstract
We report the synthesis and the reactivity of 1,2,3‐triazolin‐5‐imine type mesoionic imines (MIIs). The MIIs are accessible by a base‐mediated cycloaddition between a substituted acetonitrile and an aromatic azide, methylation by established routes and subsequent deprotonation. C=O‐stretching frequencies in MII−CO2 and −Rh(CO)2Cl complexes were used to determine the overall donor strength. The MIIs are stronger donors than the N‐heterocyclic imines (NHIs). MIIs are excellent ligands for main group elements and transition metals in which they display substituent‐induced fluorine‐specific interactions and undergo C−H activation. DFT calculations gave insights into the frontier orbitals of the MIIs. The calculations predict a relatively small HOMO–LUMO gap compared to other related ligands. MIIs are potentially able to act as both π‐donor and π‐acceptor ligands. This report highlights the potential of MIIs to display exciting properties with a huge potential for future development.
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Affiliation(s)
- Richard Rudolf
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Nicolás I. Neuman
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
- Instituto de Desarrollo Tecnológico para la Industria Química INTEC, UNL-CONICET Predio CONICET Santa Fe “Dr. Alberto Cassano” Colectora Ruta Nacional 168, Km 0 Paraje El Pozo S3000ZAA) Santa Fe Argentina
| | - Robert R. M. Walter
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Mark. R. Ringenberg
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
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15
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Huang S, Wu Y, Huang L, Hu C, Yan X. Synthesis, Characterization and Photophysical Properties of Mesoionic N-Heterocyclic Imines. Chem Asian J 2022; 17:e202200281. [PMID: 35502454 DOI: 10.1002/asia.202200281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/19/2022] [Indexed: 11/09/2022]
Abstract
N -heterocyclic imines are widely used in transition-metal chemistry, main-group chemistry as well as catalysis, due to their enhanced basicity and nucleophilicity which benefit from their ylidic form. As their analogs, mesoionic N -heterocyclic imines, which feature more highly ylidic form, is still in its infancy though excellent works also achieved. Here we reported the synthesis, characterization and photophysical properties of mesoionic N -heterocyclic imines. TD-DFT are employed to get deeper insight into the mechanism of the photophysical behaviors. The unsubstituted mesoionic N-heterocyclic imines ( 1-3 ) displayed considerable quantum yields (QY: up to 43.8%) and could be potentially applied as luminescent materials.
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Affiliation(s)
| | - Yixin Wu
- Renmin University of China, Chemistry, CHINA
| | | | - Chubin Hu
- Renmin University of China, Chemistry, CHINA
| | - Xiaoyu Yan
- Renmin University of China, Department of Chemistry, Renmin University of China, Beijing 100872, China, 100872, Beijing, CHINA
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16
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Rudolf R, Neuman NI, Walter RRM, Ringenberg MR, Sarkar B. Mesoionische Imine (MIIs): Starke Donoren und vielseitige Liganden für Übergangsmetalle und Hauptgruppensubstrate. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Richard Rudolf
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Nicolás I. Neuman
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
- Instituto de Desarrollo Tecnológico para la Industria Química CINTEC, VUNL-CONICET VPredio CONICET Santa Fe “Dr. Alberto Cassano“ Colectora Ruta Nacional 168, Km 0 Paraje El Pozo S3000ZAA) Santa Fe Argentinien
| | - Robert R. M. Walter
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Mark. R. Ringenberg
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie Institut für Anorganische Chemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Deutschland
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17
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Deka H, Fridman N, Eisen MS. A Sacrificial Iminato Ligand in the Catalytic Cyanosilylation of Ketones Promoted by Organoactinide Complexes. Inorg Chem 2022; 61:3598-3606. [PMID: 35170954 DOI: 10.1021/acs.inorgchem.1c03646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Four new complexes containing the bis(pentamethylcyclopentadienyl)thorium(IV) moiety, Cp*2Th(L1)(Me) (Th2), Cp*2Th(L2)(Me) (Th3), Cp*2Th(L1)Cl (Th5), and Cp*2Th(L2)Cl (Th6), were synthesized in quantitative yields via the protonolysis reaction of the metallocene precursor complexes Cp*2Th(Me)2 (Th1) and Cp*2Th(Me)Cl (Th4) and the respective six- and seven-membered N-heterocyclic neutral imine ligands L1H and L2H. The molecular structures of all the complexes were established by single-crystal X-ray structure analyses. The synthesized complexes along with the precursor complexes were employed as catalysts for the cyanosilylation reaction of ketones with trimethylsilyl cyanide (Me3SiCN). The removal of the iminato ligand is necessary to trigger the reaction, allowing the formation of the active catalyst.
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Affiliation(s)
- Hemanta Deka
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa City 3200003, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa City 3200003, Israel
| | - Moris S Eisen
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa City 3200003, Israel
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18
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Karmakar H, Anga S, Panda TK, Chandrasekhar V. Aluminium alkyl complexes supported by imino-phosphanamide ligand as precursors for catalytic guanylation reactions of carbodiimides. RSC Adv 2022; 12:4501-4509. [PMID: 35425514 PMCID: PMC8981115 DOI: 10.1039/d2ra00242f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 01/13/2023] Open
Abstract
Herein, we report the synthesis, characterisation, and application of three aluminium alkyl complexes, [κ2-{NHIRP(Ph)NDipp}AlMe2] (R = Dipp (2a), Mes (2b); tBu (2c), Dipp = 2,6-diisopropylphenyl, Mes = mesityl, and tBu = tert-butyl), supported by unsymmetrical imino-phosphanamide [NHIRP(Ph)NDipp]− [R = Dipp (1a), Mes (1b), tBu (1c)] ligands as molecular precursors for the catalytic synthesis of guanidines using carbodiimides and primary amines. All the imino-phosphanamide ligands 1a, 1b and 1c were prepared in good yield from the corresponding N-heterocyclic imine (NHI) with phenylchloro-2,6-diisopropylphenylphosphanamine, PhP(Cl)NHDipp. The aluminium alkyl complexes 2a, 2b and 2c were obtained in good yield upon completion of the reaction between trimethyl aluminium and the protic ligands 1a, 1b and 1c in a 1 : 1 molar ratio in toluene via the elimination of methane, respectively. The molecular structures of the protic ligands 1b and 1c and the aluminium complexes 2a, 2b and 2c were established via single-crystal X-ray diffraction analysis. Complexes 2a, 2b and 2c were tested as pre-catalysts for the hydroamination/guanylation reaction of carbodiimides with aryl amines to afford guanidines at ambient temperature. All the aluminium complexes exhibited a high conversion with 1.5 mol% catalyst loading and broad substrate scope with a wide functional group tolerance during the guanylation reaction. We also proposed the most plausible mechanism, involving the formation of catalytically active three-coordinate Al species as the active pre-catalyst. Three aluminium alkyl complexes, [κ2-{ImRNP(Ph)NDipp}AlMe2] (2a–2c), supported by unsymmetrical imino-phosphanamide were synthesised and utilised as competent precatalysts for the hydroamination of carbodiimides under ambient conditions.![]()
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Affiliation(s)
- Himadri Karmakar
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, Telangana, India
| | - Srinivas Anga
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, 500107, Hyderabad, India
| | - Tarun K. Panda
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, Telangana, India
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, 500107, Hyderabad, India
- Department of Chemistry, IIT Kanpur, Kanpur 208016, India
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19
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Deka H, Fridman N, Koneczny M, Tamm M, Eisen MS. Base-free transfer hydrogenation of aldehydes and ketones catalyzed by imidazolin-2-iminato actinide complexes. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01362b] [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
A series of thorium and uranium complexes decorated with unsymmetrical imidazolin-2-iminato ligands were found to be effective as catalysts in the transfer hydrogenation of aldehydes and ketones with 2-propanol to form the corresponding alcohols.
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Affiliation(s)
- Hemanta Deka
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa, 3200008, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa, 3200008, Israel
| | - Marvin Koneczny
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Brauschweig, Germany
| | - Moris S. Eisen
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa, 3200008, Israel
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20
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Anga S, Karmakar H, Panda TK, Chandrasekhar V. Alkali metal complexes of an unsymmetrical imino–phosphanamidinate (N-P-N) ligand. J Organomet Chem 2021. [DOI: 10.1016/j.jorganchem.2021.122091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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21
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Synthesis of mono- and bis- benzimidazolin-2-iminato titanium complexes and their catalytic performances in ethylene homo- and co- polymerizations. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2021.111974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Xu S, Wang J, Zhai J, Wang F, Pan L, Shi X. Imidazoline-2-imine Functionalized Fluorenyl Rare-Earth Metal Complexes: Synthesis and Their Application in the Polymerization of ortho-Methoxystyrene. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00439] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Suting Xu
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
| | - Jixing Wang
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
| | - Jingjing Zhai
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
| | - Fei Wang
- Tianjin Key Lab of Composite & Functional Materials, School of Material Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Li Pan
- Tianjin Key Lab of Composite & Functional Materials, School of Material Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Xiaochao Shi
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
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23
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Weitkamp RF, Neumann B, Stammler H, Hoge B. Phosphorus-Containing Superbases: Recent Progress in the Chemistry of Electron-Abundant Phosphines and Phosphazenes. Chemistry 2021; 27:10807-10825. [PMID: 34032319 PMCID: PMC8362139 DOI: 10.1002/chem.202101065] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Indexed: 01/11/2023]
Abstract
The renaissance of Brønsted superbases is primarily based on their pronounced capacity for a large variety of chemical transformations under mild reaction conditions. Four major set screws are available for the selective tuning of the basicity: the nature of the basic center (N, P, …), the degree of electron donation by substituents to the central atom, the possibility of charge delocalization, and the energy gain by hydrogen bonding. Within the past decades, a plethora of neutral electron-rich phosphine and phosphazene bases have appeared in the literature. Their outstanding properties and advantages over inorganic or charged bases have now made them indispensable as auxiliary bases in deprotonation processes. Herein, an update of the chemistry of basic phosphines and phosphazenes is given. In addition, due to widespread interest, their use in catalysis or as ligands in coordination chemistry is highlighted.
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Affiliation(s)
- Robin F. Weitkamp
- Centrum für Molekulare MaterialienFakultät für ChemieUniversität BielefeldUniversitätsstraße 2533615BielefeldGermany
| | - Beate Neumann
- Centrum für Molekulare MaterialienFakultät für ChemieUniversität BielefeldUniversitätsstraße 2533615BielefeldGermany
| | - Hans‐Georg Stammler
- Centrum für Molekulare MaterialienFakultät für ChemieUniversität BielefeldUniversitätsstraße 2533615BielefeldGermany
| | - Berthold Hoge
- Centrum für Molekulare MaterialienFakultät für ChemieUniversität BielefeldUniversitätsstraße 2533615BielefeldGermany
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24
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Jin PB, Luo QC, Zhai YQ, Wang YD, Ma Y, Tian L, Zhang X, Ke C, Zhang XF, Lv Y, Zheng YZ. A study of cation-dependent inverse hydrogen bonds and magnetic exchange-couplings in lanthanacarborane complexes. iScience 2021; 24:102760. [PMID: 34278267 PMCID: PMC8271178 DOI: 10.1016/j.isci.2021.102760] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/07/2021] [Accepted: 06/18/2021] [Indexed: 11/25/2022] Open
Abstract
Ten lanthanacarborane complexes were synthesized to study the rare B-Hδ-∙∙∙Mn+ inverse hydrogen bonds (IHBs). The average bonding energy of B-Hδ-∙∙∙Ln3+ is theoretically determined to be larger than 24 kJ/mol, which is comparable to moderately strong hydrogen bonds (21-56 kJ/mol). In addition to NMR and IR, magnetometer was used to study the exchange-coupling interaction via such B-Hδ-∙∙∙Ln3+ IHBs in detail, and the coupling constant is determined to be -2.0 cm-1, which is strong enough to compare with single-atom bridged dysprosium(III) complexes. Two imidazolin-iminato incorporated complexes have shown energy barrier for magnetization reversal larger than 1000 K, and the exchange-biasing effects are evident. Moreover, the bonding strengths of B-Hδ-∙∙∙Mn+ IHBs are cation-dependent. If M = Na, the B-Hδ-∙∙∙Na+ bonding energy is reduced to 14 kJ/mol, and the dimerization process is no longer reversible. The exchange-biasing effect is also disappeared. We believe such a finding extends our knowledge of IHBs.
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Affiliation(s)
- Peng-Bo Jin
- Frontier Institute of Science and Technology (FIST), Xi'an Jiaotong University Shenzhen Research School, State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi, P.R. China
| | - Qian-Cheng Luo
- Frontier Institute of Science and Technology (FIST), Xi'an Jiaotong University Shenzhen Research School, State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi, P.R. China
| | - Yuan-Qi Zhai
- Frontier Institute of Science and Technology (FIST), Xi'an Jiaotong University Shenzhen Research School, State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi, P.R. China
| | - Yi-Dian Wang
- Frontier Institute of Science and Technology (FIST), Xi'an Jiaotong University Shenzhen Research School, State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi, P.R. China
| | - Yan Ma
- Frontier Institute of Science and Technology (FIST), Xi'an Jiaotong University Shenzhen Research School, State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi, P.R. China
| | - Lei Tian
- State Key Laboratory of Military Stomatology, National Clinical Research Center of Oral Diseases, Shaanxi Key Laboratory of Oral Diseases, Department of Cranio-facial Trauma and Orthognathic Surgery, School of Stomatology, The Fourth Military Medical University, Xi'an, No. 145, Changle Xi Road, 710032 Xi'an, Shaanxi, P.R. China
| | - Xinliang Zhang
- Department of Spine Surgery, Honghui Hospital, Xi'an Jiaotong University, 710054 Xi'an, Shaanxi, P.R. China
| | - Chao Ke
- Department of Orthopaedic Trauma, Honghui Hospital, College of Medicine, Xi'an Jiaotong University, 710054 Xi'an, Shaanxi, P.R. China
| | - Xu-Feng Zhang
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, 277 West Yanta Road, 710061 Xi'an, Shaanxi, P.R. China
| | - Yi Lv
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, 277 West Yanta Road, 710061 Xi'an, Shaanxi, P.R. China
| | - Yan-Zhen Zheng
- Frontier Institute of Science and Technology (FIST), Xi'an Jiaotong University Shenzhen Research School, State Key Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi, P.R. China
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25
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Denker L, Trzaskowski B, Frank R. "Give me five" - an amino imidazoline-2-imine ligand stabilises the first neutral five-membered cyclic triel(I) carbenoides. Chem Commun (Camb) 2021; 57:2816-2819. [PMID: 33605974 DOI: 10.1039/d1cc00010a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present the first cyclic five-membered triel(i) carbenoides E(AmIm) for E = Ga, In, Tl; AmIm = amido imidazoline-2-imine, which fill the current gap between four- and six-membered triel(i) carbenoides supported by HGiso and HNacNac. Ga(AmIm) can act as a strong σ-donor ligand in transition metal complexes, while the intermediacy of the Al(i) carbenoide Al(AmIm) is rationalised based on the isolation of an Al(iii) insertion product.
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Affiliation(s)
- Lars Denker
- Institute of Inorganic and Analytical Chemistry, Technische Universität Braunschweig, Hagenring 30, Braunschweig 38106, Germany.
| | - Bartosz Trzaskowski
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warszawa 02-097, Poland.
| | - René Frank
- Institute of Inorganic and Analytical Chemistry, Technische Universität Braunschweig, Hagenring 30, Braunschweig 38106, Germany.
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26
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Dolati H, Denker L, Trzaskowski B, Frank R. Superseding β-Diketiminato Ligands: An Amido Imidazoline-2-Imine Ligand Stabilizes the Exhaustive Series of B=X Boranes (X=O, S, Se, Te). Angew Chem Int Ed Engl 2021; 60:4633-4639. [PMID: 33283430 PMCID: PMC7986232 DOI: 10.1002/anie.202015553] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Indexed: 01/01/2023]
Abstract
Boron reluctantly forms B=X (X=O, S, Se, Te) moieties, which has stimulated the quest for such species in the past few years. Based on the N,N'-chelating β-diketiminato ligand (HNacNac), a new amido imidazoline-2-imine ligand system (HAmIm) is presented, giving rise to the isolation of an exhaustive series of Lewis acid free, monomeric chalcogen B=X boranes with documented π-bond character between boron and the chalcogen. The chalcogenoboranes are isoelectronic and isolobal to the respective ketones. The chemical behavior of the oxoborane (B=O) strongly resembles the classical carbonyl reactivity in C=O bonds. The improved stability provided by HAmIm arises from the formation of more-stable five-membered boron chelates versus the six-membered NacNac analogues and from the imidazoline-2-imine moiety providing enhanced σ- and π-donation. The HAmIm ligand class may supersede the widely employed NacNac system in certain applications.
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Affiliation(s)
- Hadi Dolati
- Institute of Inorganic and Analytical ChemistryTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Lars Denker
- Institute of Inorganic and Analytical ChemistryTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Bartosz Trzaskowski
- Centre of New TechnologiesUniversity of WarsawBanacha 2C02-097WarszawaPoland
| | - René Frank
- Institute of Inorganic and Analytical ChemistryTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
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27
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Anga S, Acharya J, Chandrasekhar V. An Unsymmetric Imino-Phosphanamidinate Ligand and its Y(III) Complex: Synthesis, Characterization, and Catalytic Hydroboration of Carbonyl Compounds. J Org Chem 2021; 86:2224-2234. [PMID: 33290079 DOI: 10.1021/acs.joc.0c02383] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An imino-phosphanamide ligand, [NHIiPr2Me2P(Ph)NH-2,6-iPr2C6H3] (LH), containing two different N-substituents was prepared by the direct reaction of the lithium salt of N-heterocyclic imine (NHI) with phenylchloro-2,6-diisopropylphenyl phosphanamine, PhP(Cl)NH-2,6-iPr2-C6H3. Reaction of LH with Y(N(SiMe3)2)3 afforded the heteroleptic complex, [{L}Y(N(SiMe3)2)2] (1), by elimination of HN(SiMe3)2. Compound 1 was characterized by multinuclear NMR and X-ray crystallography. In the complex, the Y(III) center was found to be tetracoordinate in a distorted tetrahedral geometry. The ligand, imino-phosphanamidinate, [L]-, functions in a chelating manner, and its coordination to Y(III) results in a distorted 4-membered YPN2 ring. As a proof of principle of its activity, 1 was used as a precatalyst for the hydroboration of various aldehydes and ketones using HBpin as the hydrogen source. The hydroboration reaction was rapid and clean even with low catalyst loadings (0.01-0.1 mol %). In addition, a very good functional group tolerance was observed in these reactions.
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Affiliation(s)
- Srinivas Anga
- Tata Institute of Fundamental Research Hyderabad, Gopanpally 500046, Hyderabad, India
| | - Joydev Acharya
- Tata Institute of Fundamental Research Hyderabad, Gopanpally 500046, Hyderabad, India.,Department of Chemistry, IIT Kanpur, Kanpur 208016, India
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research Hyderabad, Gopanpally 500046, Hyderabad, India.,Department of Chemistry, IIT Kanpur, Kanpur 208016, India
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28
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Dolati H, Denker L, Trzaskowski B, Frank R. Superseding β‐Diketiminato Ligands: An Amido Imidazoline‐2‐Imine Ligand Stabilizes the Exhaustive Series of B=X Boranes (X=O, S, Se, Te). Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202015553] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Hadi Dolati
- Institute of Inorganic and Analytical Chemistry Technische Universität Braunschweig Hagenring 30 38106 Braunschweig Germany
| | - Lars Denker
- Institute of Inorganic and Analytical Chemistry Technische Universität Braunschweig Hagenring 30 38106 Braunschweig Germany
| | - Bartosz Trzaskowski
- Centre of New Technologies University of Warsaw Banacha 2C 02-097 Warszawa Poland
| | - René Frank
- Institute of Inorganic and Analytical Chemistry Technische Universität Braunschweig Hagenring 30 38106 Braunschweig Germany
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29
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Anga S, Chandra S, Sarkar P, Das S, Mandal D, Kundu A, Rawat H, Schulzke C, Sarkar B, Pati SK, Chandrasekhar V, Jana A. Facile One‐Pot Assembly of Push–Pull Imines by a Selective C–F Substitution Process in Aryl Fluorides. European J Org Chem 2020. [DOI: 10.1002/ejoc.202001344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Srinivas Anga
- Gopanpally Tata Institute of Fundamental Research Hyderabad 500107 Hyderabad India
| | - Shubhadeep Chandra
- Institut für Chemie und Biochemie, Anorganische Chemie Freie Universität Berlin Fabeckstraße 34‐36 14195 Berlin Germany
- Fakultät Chemie Lehrstuhl für Anorganische Koordinationschemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Pallavi Sarkar
- Theoretical Sciences Unit Jawaharlal Nehru Centre for Advanced Scientific Research 560064 Bangalore India
| | - Shubhajit Das
- Theoretical Sciences Unit Jawaharlal Nehru Centre for Advanced Scientific Research 560064 Bangalore India
| | - Debdeep Mandal
- Gopanpally Tata Institute of Fundamental Research Hyderabad 500107 Hyderabad India
| | - Abhinanda Kundu
- Gopanpally Tata Institute of Fundamental Research Hyderabad 500107 Hyderabad India
| | - Hemant Rawat
- Gopanpally Tata Institute of Fundamental Research Hyderabad 500107 Hyderabad India
| | - Carola Schulzke
- Institut für Biochemie Universität Greifswald Felix‐Hausdorff‐Straße 4 17487 Greifswald Germany
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie Freie Universität Berlin Fabeckstraße 34‐36 14195 Berlin Germany
- Fakultät Chemie Lehrstuhl für Anorganische Koordinationschemie Universität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Swapan K. Pati
- Theoretical Sciences Unit Jawaharlal Nehru Centre for Advanced Scientific Research 560064 Bangalore India
| | - Vadapalli Chandrasekhar
- Gopanpally Tata Institute of Fundamental Research Hyderabad 500107 Hyderabad India
- Department of Chemistry Indian Institute of Technology Kanpur 208016 Kanpur India
| | - Anukul Jana
- Gopanpally Tata Institute of Fundamental Research Hyderabad 500107 Hyderabad India
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30
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Expedient Synthetic Identification of a P‐Stereogenic Ligand Motif for the Palladium‐Catalyzed Preparation of Isotactic Polar Polypropylenes. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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31
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Seidel FW, Tomizawa I, Nozaki K. Expedient Synthetic Identification of a P‐Stereogenic Ligand Motif for the Palladium‐Catalyzed Preparation of Isotactic Polar Polypropylenes. Angew Chem Int Ed Engl 2020; 59:22591-22601. [DOI: 10.1002/anie.202009027] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/01/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Falk William Seidel
- Department of Chemistry and Biotechnology Graduate School of Engineering The University of Tokyo 7-3-1- Hongo, Bunkyo-ku Tokyo 113-8656 Japan
| | - Izumi Tomizawa
- Department of Chemistry and Biotechnology Graduate School of Engineering The University of Tokyo 7-3-1- Hongo, Bunkyo-ku Tokyo 113-8656 Japan
| | - Kyoko Nozaki
- Department of Chemistry and Biotechnology Graduate School of Engineering The University of Tokyo 7-3-1- Hongo, Bunkyo-ku Tokyo 113-8656 Japan
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32
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Tschernuth FS, Hanusch F, Szilvási T, Inoue S. Isolation and Reactivity of Chlorotetryliumylidenes Using a Bidentate Bis(N-heterocyclic imine) Ligand. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00320] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Florian S. Tschernuth
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching bei München, Germany
| | - Franziska Hanusch
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching bei München, Germany
| | - Tibor Szilvási
- Department of Chemical and Biological Engineering, University of Wisconsin—Madison, 1415 Engineering Drive, Madison, Wisconsin 53706-1607, United States
| | - Shigeyoshi Inoue
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching bei München, Germany
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33
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Bockfeld D, Tamm M. Isolation of N‐Heterocyclic Carbene‐Stabilized Phosphorus and Arsenic Mononitride. Z Anorg Allg Chem 2020. [DOI: 10.1002/zaac.202000094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Dirk Bockfeld
- Institut für Anorganische und Analytische Chemie Technische Universität Braunschweig Hagenring 30 38106 Braunschweig Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie Technische Universität Braunschweig Hagenring 30 38106 Braunschweig Germany
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34
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Wilm LF, Mehlmann P, Buß F, Dielmann F. Synthesis and characterization of strongly electron-donating bidentate phosphines containing imidazolin-2-ylidenamino substituents and their electron-rich nickel(0), palladium(II) and gold(I) chelate complexes. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2019.121097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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35
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Goettel JT, Gao H, Dotzauer S, Braunschweig H. Me CAAC=N - : A Cyclic (Alkyl)(Amino)Carbene Imino Ligand. Chemistry 2020; 26:1136-1143. [PMID: 31777982 PMCID: PMC7027825 DOI: 10.1002/chem.201904715] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Indexed: 12/27/2022]
Abstract
A cyclic (alkyl)(amino)carbene (CAAC) has been shown to react with a covalent azide similar to the Staudinger reaction. The reaction of Me CAAC with trimethylsilyl azide afforded the N-silylated 2-iminopyrrolidine (Me CAAC=NSiMe3 ), which was fully characterized. This compound undergoes hydrolysis to afford the 2-iminopyrrolidine and trimethylsiloxane which co-crystallize as a hydrogen-bonded adduct. The N-silylated 2-iminopyrrolidine was used to transfer the novel pyrrolidine-2-iminato ligand onto both main-group and transition-metal centers. The reaction of the tetrabromodiborane bis(dimethyl sulfide) adduct with two equivalents of Me CAAC=NSiMe3 afforded the disubstituted diborane. The reaction of Me CAAC=NSiMe3 with TiCl4 and CpTiCl3 afforded Me CAAC=NTiCl3 and Me CAAC=NTiCl2 Cp, respectively.
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Affiliation(s)
- James T. Goettel
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Haopeng Gao
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Simon Dotzauer
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Holger Braunschweig
- Institute for Inorganic ChemistryJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
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36
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Ho LP, Körner L, Bannenberg T, Tamm M. Chalcogen complexes of anionic N-heterocyclic carbenes. Dalton Trans 2020; 49:13207-13217. [DOI: 10.1039/d0dt02392b] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Chalcogen complexes of anionic N-heterocyclic carbenes were isolated as lithium salts and their protonation and oxidation were studied.
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Affiliation(s)
- Luong Phong Ho
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Brauschweig
- Germany
| | - Lukas Körner
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Brauschweig
- Germany
| | - Thomas Bannenberg
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Brauschweig
- Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Brauschweig
- Germany
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37
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Peters M, Baabe D, Maekawa M, Bockfeld D, Zaretzke MK, Tamm M, Walter MD. Pogo-Stick Iron and Cobalt Complexes: Synthesis, Structures, and Magnetic Properties. Inorg Chem 2019; 58:16475-16486. [PMID: 31769666 DOI: 10.1021/acs.inorgchem.9b02411] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis, structures, and magnetic properties of monomeric half-sandwich iron and cobalt imidazolin-2-iminato complexes have been comprehensively investigated. Salt metathesis reactions of [Cp'M(μ-I)]2 (1-M, M = Fe, Co; Cp' = η5-1,2,4-tri-tert-butylcyclopentadienyl) with [ImDippNLi]2 (ImDippN = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-iminato) furnishes the terminal half-sandwich compounds [Cp'M(NImDipp)] (2-M, M = Fe, Co), which can be regarded as models for elusive half-sandwich iron and cobalt imido complexes. X-ray diffraction analysis confirmed the structure motif of a one-legged piano stool. Complex 2-Co can also be prepared by an acid-base reaction between [Cp'Co{N(SiMe3)2}] (3-Co) and ImDippNH. The electronic and magnetic properties of 2-M and 3-Co were probed by 57Fe Mössbauer spectroscopy (M = Fe), X-band EPR spectroscopy (M = Co), and solid-state magnetic susceptibility measurements. In particular, the central metal atom adopts a high-spin (S = 2) state in 2-Fe, while the cobalt complex 2-Co represents a rare example of a Co(II) species with a coordination number different from six displaying a low-spin to high-spin spin-crossover (SCO) behavior. The experimental observations are complemented by DFT calculations.
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Affiliation(s)
- Marius Peters
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
| | - Dirk Baabe
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
| | - Miyuki Maekawa
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
| | - Dirk Bockfeld
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
| | - Marc-Kevin Zaretzke
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
| | - Marc D Walter
- Institut für Anorganische und Analytische Chemie , Technische Universität Braunschweig , Hagenring 30 , 38106 Braunschweig , Germany
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38
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Isolation, characterization and reactivity of three-coordinate phosphorus dications isoelectronic to alanes and silylium cations. Nat Chem 2019; 11:1139-1143. [DOI: 10.1038/s41557-019-0348-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 08/30/2019] [Indexed: 11/08/2022]
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39
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Boom DHA, Jupp AR, Nieger M, Ehlers AW, Slootweg JC. New Insights in Frustrated Lewis Pair Chemistry with Azides. Chemistry 2019; 25:13299-13308. [PMID: 31497899 PMCID: PMC6851766 DOI: 10.1002/chem.201902710] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Indexed: 12/16/2022]
Abstract
The geminal frustrated Lewis pair (FLP) tBu2 PCH2 BPh2 (1) reacts with phenyl-, mesityl-, and tert-butyl azide affording, respectively, six, five, and four-membered rings as isolable products. DFT calculations revealed that the formation of all products proceeds via the six-membered ring structure, which is thermally stable with an N-phenyl group, but rearranges when sterically more encumbered Mes-N3 and tBu-N3 are used. The reaction of 1 with Me3 Si-N3 is believed to follow the same course, yet subsequent N2 elimination occurs to afford a four-membered heterocycle (5), which can be considered as a formal FLP-trimethylsilylnitrene adduct. Compound 5 reacts with hydrochloric acid or tetramethylammonium fluoride and showed frustrated Lewis pair reactivity towards phenylisocyanate.
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Affiliation(s)
- Devin H. A. Boom
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
| | - Andrew R. Jupp
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
| | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio 1, PO Box 5500014HelsinkiFinland
| | - Andreas W. Ehlers
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
- Department of Chemistry, Science FacultyUniversity of JohannesburgPO Box 254Auckland Park, JohannesburgSouth Africa
| | - J. Chris Slootweg
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamScience Park 9041090 GDAmsterdamThe Netherlands
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40
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Benaissa I, Pallova L, Morantin ME, Lafitte T, Huynh M, Barthes C, Vendier L, Lugan N, Bastin S, César V. N-Heterocyclic Carbenes as Key Intermediates in the Synthesis of Fused, Mesoionic, Tricyclic Heterocycles. Chemistry 2019; 25:13030-13036. [PMID: 31385630 DOI: 10.1002/chem.201903242] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Indexed: 01/16/2023]
Abstract
Coupling between 5-bromoimidazo[1,5-a]pyridinium salts and malonate or arylacetate esters leads to a facile and straightforward access to the new mesoionic, fused, tricyclic system of imidazo[2,1,5-cd]indolizinium-3-olate. Mechanistic studies show that the reaction pathway consists of nucleophilic aromatic substitution on the cationic, bicyclic heterocycle by an enolate-type moiety and in the nucleophilic attack of a transient free N-heterocyclic carbene (NHC) species on the ester group; the relative order of these two steps depends on the nature of the starting ester. This work highlights the valuable implementation of free NHC species as key intermediates in synthetic chemistry, beyond their classical use as stabilizing ligands or organocatalysts.
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Affiliation(s)
- Idir Benaissa
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | - Lenka Pallova
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | | | - Thomas Lafitte
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | - Mathieu Huynh
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | - Cécile Barthes
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | - Laure Vendier
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | - Noël Lugan
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
| | | | - Vincent César
- LCC-CNRS, Université de Toulouse, CNRS, Toulouse, 31077, France
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41
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Liu H, Khononov M, Fridman N, Tamm M, Eisen MS. (Benz)Imidazolin-2-iminato Aluminum, Zinc, and Magnesium Complexes and Their Applications in Ring Opening Polymerization of ε-Caprolactone. Inorg Chem 2019; 58:13426-13439. [PMID: 31556598 DOI: 10.1021/acs.inorgchem.9b02324] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Heng Liu
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Haifa City, 32000, Israel
| | - Maxim Khononov
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Haifa City, 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Haifa City, 32000, Israel
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Moris S. Eisen
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Haifa City, 32000, Israel
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42
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Liu BC, Ge N, Zhai YQ, Zhang T, Ding YS, Zheng YZ. An imido ligand significantly enhances the effective energy barrier of dysprosium(iii) single-molecule magnets. Chem Commun (Camb) 2019; 55:9355-9358. [PMID: 31314022 DOI: 10.1039/c9cc04687a] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report herein an imido ligand 1,3-bis(2,6-diisopropylphenyl) imidazolin-2-imine (ImDippNH) that can form a very short Dy-N bond (2.12 Å) with the dysprosium(iii) ion, which leads to a much larger effective energy barrier for magnetisation reversal (803 K) compared to the analogous alkoxide ligand (53 K). Moreover, we predict that a linear two-coordinate [Dy(ImDippN)2]+ complex may have an effective energy barrier larger than 4000 K.
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Affiliation(s)
- Bing-Cheng Liu
- Frontier Institute of Science and Technology (FIST), State Key Laboratory of Mechanical Behaviour for Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.
| | - Ning Ge
- Frontier Institute of Science and Technology (FIST), State Key Laboratory of Mechanical Behaviour for Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.
| | - Yuan-Qi Zhai
- Frontier Institute of Science and Technology (FIST), State Key Laboratory of Mechanical Behaviour for Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.
| | - Tao Zhang
- Frontier Institute of Science and Technology (FIST), State Key Laboratory of Mechanical Behaviour for Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.
| | - You-Song Ding
- Frontier Institute of Science and Technology (FIST), State Key Laboratory of Mechanical Behaviour for Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.
| | - Yan-Zhen Zheng
- Frontier Institute of Science and Technology (FIST), State Key Laboratory of Mechanical Behaviour for Materials, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy and Materials Chemistry and School of Science, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China. and Shenzhen Research School, Xian Jiaotong University, China
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43
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Doddi A, Peters M, Tamm M. N-Heterocyclic Carbene Adducts of Main Group Elements and Their Use as Ligands in Transition Metal Chemistry. Chem Rev 2019; 119:6994-7112. [PMID: 30983327 DOI: 10.1021/acs.chemrev.8b00791] [Citation(s) in RCA: 290] [Impact Index Per Article: 58.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
N-Heterocyclic carbenes (NHC) are nowadays ubiquitous and indispensable in many research fields, and it is not possible to imagine modern transition metal and main group element chemistry without the plethora of available NHCs with tailor-made electronic and steric properties. While their suitability to act as strong ligands toward transition metals has led to numerous applications of NHC complexes in homogeneous catalysis, their strong σ-donating and adaptable π-accepting abilities have also contributed to an impressive vitalization of main group chemistry with the isolation and characterization of NHC adducts of almost any element. Formally, NHC coordination to Lewis acids affords a transfer of nucleophilicity from the carbene carbon atom to the attached exocyclic moiety, and low-valent and low-coordinate adducts of the p-block elements with available lone pairs and/or polarized carbon-element π-bonds are able to act themselves as Lewis basic donor ligands toward transition metals. Accordingly, the availability of a large number of novel NHC adducts has not only produced new varieties of already existing ligand classes but has also allowed establishment of numerous complexes with unusual and often unprecedented element-metal bonds. This review aims at summarizing this development comprehensively and covers the usage of N-heterocyclic carbene adducts of the p-block elements as ligands in transition metal chemistry.
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Affiliation(s)
- Adinarayana Doddi
- Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany
| | - Marius Peters
- Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany
| | - Matthias Tamm
- Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany
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44
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Mehlmann P, Dielmann F. Switching the Electron-Donating Ability of Phosphines through Proton-Responsive Imidazolin-2-ylidenamino Substituents. Chemistry 2019; 25:2352-2357. [PMID: 30506604 DOI: 10.1002/chem.201805540] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Indexed: 11/06/2022]
Abstract
Stimuli-responsive ancillary ligands are valuable tools to control the activity and selectivity of transition-metal catalysts. The synthesis and characterization of a series of metal complexes containing phosphines with proton-responsive imidazolin-2-ylidenamino substituents are reported. Determination of the ligand-donor properties revealed that protonation of each substituent increases the Tolman electronic parameter (TEP) of the phosphine by 22 cm-1 , hence allowing for switching of the electron-donor power of phosphine 2 within an unprecedented range (ΔTEP=43.4 cm-1 ).
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Affiliation(s)
- Paul Mehlmann
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 30, 48149, Münster, Germany
| | - Fabian Dielmann
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 30, 48149, Münster, Germany
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45
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Peters M, Bannenberg T, Bockfeld D, Tamm M. Pentamethylcyclopentadienyl ruthenium “pogo stick” complexes with nitrogen donor ligands. Dalton Trans 2019; 48:4228-4238. [DOI: 10.1039/c9dt00577c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The preparation and reactivity of an imidazolin-2-iminato ruthenium complex with a rare one-legged piano-stool (“pogo stick”) geometry is reported.
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Affiliation(s)
- Marius Peters
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Braunschweig
- Germany
| | - Thomas Bannenberg
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Braunschweig
- Germany
| | - Dirk Bockfeld
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Braunschweig
- Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie
- Technische Universität Braunschweig
- 38106 Braunschweig
- Germany
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46
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Das S, Bhattacharjee J, Panda TK. An imidazolin-2-iminato ligand organozinc complex as a catalyst for hydroboration of organic nitriles. NEW J CHEM 2019. [DOI: 10.1039/c9nj04076e] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Catalytic hydroboration of nitriles with pinacolborane (HBpin) using the imidazolin-2-iminato zinc alkyl complex [{(ImtBuN)Zn(CH2CH3)}2] (1c) under mild and solvent-free conditions to afford corresponding diboronate esters in high yield is reported.
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Affiliation(s)
- Suman Das
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy 502285
- India
| | - Jayeeta Bhattacharjee
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy 502285
- India
| | - Tarun K. Panda
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy 502285
- India
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47
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Das S, Bhattacharjee J, Panda TK. Guanylation/cyclisation of amino acid esters using an imidazolin-2-iminato titanium initiator. Dalton Trans 2019; 48:7227-7235. [DOI: 10.1039/c8dt04630a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Catalytic hydroamination of amino acid esters with carbodiimides and isocyanates to furnish corresponding quinazolinone and urea derivatives using two TiIV complexes under mild conditions is reported.
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Affiliation(s)
- Suman Das
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy 502285
- India
| | - Jayeeta Bhattacharjee
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy 502285
- India
| | - Tarun K. Panda
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy 502285
- India
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48
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Naktode K, Das S, Nayek HP, Panda TK. Reactivity of titanium imidazolin-2-iminato complexes with 2,6-diisopropylaniline and 2-{(2,6-diisopropylphenyl)-iminomethyl}pyrrole. J COORD CHEM 2018. [DOI: 10.1080/00958972.2018.1544705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Kishor Naktode
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, India
- Department of Chemistry, Nevjabai Hitkarini College Bramhapuri, Chandrapur, India
| | - Suman Das
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, India
| | - Hari Pada Nayek
- Department of Applied Chemistry, Indian Institute of Technology (ISM), Dhanbad, India
| | - Tarun K. Panda
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, India
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49
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Ehrhorn H, Tamm M. Well-Defined Alkyne Metathesis Catalysts: Developments and Recent Applications. Chemistry 2018; 25:3190-3208. [PMID: 30346054 DOI: 10.1002/chem.201804511] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Indexed: 12/31/2022]
Abstract
Although alkyne metathesis has been known for 50 years, rapid progress in this field has mostly occurred during the last two decades. In this article, the development of several highly efficient and thoroughly studied alkyne metathesis catalysts is reviewed, which includes novel well-defined, in situ formed and heterogeneous systems. Various alkyne metathesis methodologies, including alkyne cross-metathesis (ACM), ring-closing alkyne metathesis (RCAM), cyclooligomerization, acyclic diyne metathesis polymerization (ADIMET), and ring-opening alkyne metathesis polymerization (ROAMP), are presented, and their application in natural product synthesis, materials science as well as supramolecular and polymer chemistry is discussed. Recent progress in the metathesis of diynes is also summarized, which gave rise to new methods such as ring-closing diyne metathesis (RCDM) and diyne cross-metathesis (DYCM).
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Affiliation(s)
- Henrike Ehrhorn
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Matthias Tamm
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
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McSkimming A, Suess DLM. Selective Synthesis of Site-Differentiated Fe 4S 4 and Fe 6S 6 Clusters. Inorg Chem 2018; 57:14904-14912. [PMID: 30418746 DOI: 10.1021/acs.inorgchem.8b02684] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Obtaining rational control over the structure and nuclearity of metalloclusters is an ongoing challenge in synthetic Fe-S cluster chemistry. We report a new family of tridentate imidazolin-2-imine ligands L(NImR)3 that can bind [Fe4S4]2+ or [Fe6S6]3+ clusters, depending on the steric profile of the ligand and the reaction stoichiometry. A high-yielding synthetic route to L(NImR)3 ligands (where R is the imidazolyl N substituents) from trianiline and 2-chloroimidazolium precursors is described. For L(NImMe)3 (tris(1,3,5-(3-( N, N-dimethyl-4,5-diphenylimidazolin-2-imino)phenylmethyl))benzene), metalation with 1 equiv of [Ph4P]2[Fe4S4Cl4] and 3 equiv of NaBPh4 furnishes a mixture of products, but adjusting the stoichiometry to 1.5 equiv of [Ph4P]2[Fe4S4Cl4] provides (L(NImMe)3)Fe6S6Cl6 in high yield. Formation of an [Fe6S6]3+ cluster using L(NImTol)3 (tris(1,3,5-(3-( N, N-bis(4-methylphenyl)-4,5-diphenylimidazolin-2-imino)phenylmethyl))benzene) is not observed; instead, the [Fe4S4]2+ cluster [(L(NImTol)3)(Fe4S4Cl)][BPh4] is cleanly generated when 1 equiv of [Ph4P]2[Fe4S4Cl4] is employed. The selectivity for cluster nuclearity is rationalized by the orientation of the imidazolyl rings whereby long N-imidazolyl substituents preclude formation of [Fe6S6]3+ clusters but not [Fe4S4]2+ clusters. Thus, the structure and nuclearity of L(NImR)3-bound Fe-S clusters may be selectively controlled through rational modification the ligand's substituents.
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Affiliation(s)
- Alex McSkimming
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Daniel L M Suess
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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