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Amit E, Mondal R, Berg I, Nairoukh Z, Gross E. N-Heterocyclic Carbene Monolayers on Metal-Oxide Films: Correlations between Adsorption Mode and Surface Functionality. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:10374-10383. [PMID: 38701356 PMCID: PMC11100006 DOI: 10.1021/acs.langmuir.4c01109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/15/2024] [Accepted: 04/19/2024] [Indexed: 05/05/2024]
Abstract
N-Heterocyclic carbene (NHC) ligands have been self-assembled on various metal and semimetal surfaces, creating a covalent bond with surface metal atoms that led to high thermal and chemical stability of the self-assembled monolayer. This study explores the self-assembly of NHCs on metal-oxide films (CuOx, FeOx, and TiOx) and reveals that the properties of these metal-oxide substrates play a pivotal role in dictating the adsorption behavior of NHCs, influencing the decomposition route of the monolayer and its impact on work function values. While the attachment of NHCs onto CuOx is via coordination with surface oxygen atoms, NHCs interact with TiOx through coordination with surface metal atoms and with FeOx via coordination with both metal and oxygen surface atoms. These distinct binding modes arise due to variances in the electronic properties of the metal atoms within the investigated metal-oxide films. Contact angle and ultraviolet photoelectron spectroscopy measurements have shown a significantly higher impact of F-NHC adsorption on CuOx than on TiOx and FeOx , correlated to a preferred, averaged upright orientation of F-NHC on CuOx.
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Affiliation(s)
- Einav Amit
- Institute
of Chemistry, The Hebrew University, Jerusalem 91904, Israel
- The
Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem 91904, Israel
| | - Rajarshi Mondal
- Institute
of Chemistry, The Hebrew University, Jerusalem 91904, Israel
| | - Iris Berg
- Institute
of Chemistry, The Hebrew University, Jerusalem 91904, Israel
- The
Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem 91904, Israel
| | - Zackaria Nairoukh
- Institute
of Chemistry, The Hebrew University, Jerusalem 91904, Israel
| | - Elad Gross
- Institute
of Chemistry, The Hebrew University, Jerusalem 91904, Israel
- The
Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem 91904, Israel
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2
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Pankov RO, Prima DO, Kostyukovich AY, Minyaev ME, Ananikov VP. Synthesis and a combined experimental/theoretical structural study of a comprehensive set of Pd/NHC complexes with o-, m-, and p-halogen-substituted aryl groups (X = F, Cl, Br, CF 3). Dalton Trans 2023; 52:4122-4135. [PMID: 36883531 DOI: 10.1039/d2dt03665g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
Pd/NHC complexes (NHCs - N-heterocyclic carbenes) with electron-withdrawing halogen groups were prepared by developing an optimized synthetic procedure to access imidazolium salts and the corresponding metal complexes. Structural X-ray analysis and computational studies have been carried out to evaluate the effect of halogen and CF3 substituents on the Pd-NHC bond and have provided insight into the possible electronic effects on the molecular structure. The introduction of electron-withdrawing substituents changes the ratio of σ-/π-contributions to the Pd-NHC bond but does not affect the Pd-NHC bond energy. Here, we report the first optimized synthetic approach to access a comprehensive range of o-, m-, and p-XC6H4-substituted NHC ligands, including incorporation into Pd complexes (X = F, Cl, Br, CF3). The catalytic activity of the obtained Pd/NHC complexes was compared in the Mizoroki-Heck reaction. For substitution with halogen atoms, the following relative trend was observed: X = Br > F > Cl, and for all halogen atoms, the catalytic activity changed in the following order: m-X, p-X > o-X. Evaluation of the relative catalytic activity showed a significant increase in the catalyst performance in the case of Br and CF3 substituents compared to the unsubstituted Pd/NHC complex.
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Affiliation(s)
- Roman O Pankov
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Darya O Prima
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Alexander Yu Kostyukovich
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Mikhail E Minyaev
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Valentine P Ananikov
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
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3
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Demirel N, Haber J, Ivlev SI, Meggers E. Improving the Configurational Stability of Chiral-at-Iron Catalysts Containing Two N-(2-Pyridyl)-Substituted N-Heterocyclic Carbene Ligands. Organometallics 2022; 41:3852-3860. [PMID: 36590905 PMCID: PMC9795549 DOI: 10.1021/acs.organomet.2c00492] [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: 09/29/2022] [Indexed: 11/27/2022]
Abstract
Recently, we introduced the first example of chiral-at-iron catalysts in which two achiral N-(2-pyridyl)-substituted N-heterocyclic carbene (NHC) ligands in addition to two labile acetonitriles are coordinated around a central iron, to generate a stereogenic metal center [Hong Y.Chiral-at-Iron Catalyst: Expanding the Chemical Space for Asymmetric Earth-Abundant Metal Catalysis. J. Am. Chem. Soc.2019, 141, 4569-4572]. A more facile synthesis of such chiral-at-iron catalysts was developed, which omits the use of expensive silver salts and an elaborate electrochemical setup. Configurational robustness was improved by replacing the imidazol-2-ylidene carbene moieties with benzimidazol-2-ylidenes. The π-acceptor properties of the altered NHCs were investigated by Ganter's 77Se NMR method. The obtained benzimidazol-2-ylidene chiral-at-iron complex is an excellent catalyst for an asymmetric hetero-Diels-Alder reaction under open-flask conditions.
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4
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Hassen S, Zouaghi MO, Slimani I, Arfaoui Y, Namık Özdemir, Özdemir I, Gürbüz N, Mansour L, Gatri R, Hamdi N. Synthesis, crystal structures, DFT calculations, and catalytic application in hydrosilylation of acetophenone derivatives with triethylsilane of novel rhoduim-N-heterocyclic carbene (NHCs) complex. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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5
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Prima DO, Pankov RO, Kostyukovich AY, Minyaev ME, Burykina JV, Ananikov VP. Synthesis and characterization of Pd/NHC F complexes with fluorinated aryl groups. Dalton Trans 2022; 51:9843-9856. [PMID: 35708172 DOI: 10.1039/d2dt00892k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The key problem of the instability of fluorine-containing diazadienes was addressed to perform the efficient synthesis of imidazolium salts containing fluorine substituents in the aryl groups. The subsequent reaction of fluorine-containing imidazolium compounds (NHCF) with palladium salts under simple conditions afforded new Pd/NHCF complexes. Computational and structural studies were performed to assess the effect of fluorine on the Pd-NHC bond and gave insight into the electronic effects in the molecule. The introduction of fluorine substituents into the aryl rings of the NHC ligands leads to a slight decrease in their σ-donor properties. At the same time, there is a slight increase in the π-acceptor capacity of NHCF. These two effects compensate for each other, so that the Pd-NHC bonding energy remains virtually unchanged. Another observed effect is associated with a slight weakening of the trans influence of the NHCF ligands, which is expressed in the strengthening of the Pd-Solv bond in (NHC)Pd(Solv) complexes. For the first time, a series of novel Pd/NHCF complexes were synthesized via a straightforward approach from fluorine-containing anilines.
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Affiliation(s)
- Darya O Prima
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Roman O Pankov
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Alexander Yu Kostyukovich
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Mikhail E Minyaev
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Julia V Burykina
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
| | - Valentine P Ananikov
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
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6
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Tilly DP, Cullen W, Zhong H, Jamagne R, Vitórica-Yrezábal I, Webb SJ. α-Amino-iso-butyric acid foldamers terminated with rhodium(I) N-heterocyclic carbene catalysts. Chemistry 2021; 28:e202104293. [PMID: 34932229 PMCID: PMC9305545 DOI: 10.1002/chem.202104293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Indexed: 12/01/2022]
Abstract
To investigate how remotely induced changes in ligand folding might affect catalysis by organometallic complexes, dynamic α‐amino‐iso‐butyric acid (Aib) peptide foldamers bearing rhodium(I) N‐heterocyclic carbene (NHC) complexes have been synthesized and studied. X‐ray crystallography of a foldamer with an N‐terminal azide and a C‐terminal Rh(NHC)(Cl)(diene) complex showed a racemate with a chiral axis in the Rh(NHC) complex and a distorted 310 helical body. Replacing the azide with either one or two chiral L‐α‐methylvaline (L‐αMeVal) residues gave diastereoisomeric foldamers that each possessed point, helical and axial chirality. NMR spectroscopy revealed an unequal ratio of diastereoisomers for some foldamers, indicating that the chiral conformational preference of the N‐terminal residue(s) was relayed down the 1 nm helical body to the axially chiral Rh(NHC) complex. Although the remote chiral residue(s) did not affect the stereoselectivity of hydrosilylation reactions catalysed by these foldamers, these studies suggest a potential pathway towards remote conformational control of organometallic catalysts.
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Affiliation(s)
- David P Tilly
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | - William Cullen
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | - Heng Zhong
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | - Romain Jamagne
- The University of Manchester, Department of Chemistry, UNITED KINGDOM
| | | | - Simon John Webb
- University of Manchester, School of Chemistry and MIB, 131 Princess St, M1 7DN, Manchester, UNITED KINGDOM
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7
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Barnett C, Cole ML, Harper JB. Steric Properties of
N
‐Heterocyclic Carbenes affect the Performance of Electronic Probes. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100796] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Christopher Barnett
- School of Chemistry University of New South Wales UNSW Sydney NSW 2052 Sydney Australia
- School of Chemistry The University of Sydney Sydney NSW 2006 Australia
| | - Marcus L. Cole
- School of Chemistry University of New South Wales UNSW Sydney NSW 2052 Sydney Australia
| | - Jason B. Harper
- School of Chemistry University of New South Wales UNSW Sydney NSW 2052 Sydney Australia
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8
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Ma X, Guillet SG, Liu Y, Cazin CSJ, Nolan SP. Simple synthesis of [Ru(CO 3)(NHC)( p-cymene)] complexes and their use in transfer hydrogenation catalysis. Dalton Trans 2021; 50:13012-13019. [PMID: 34581364 DOI: 10.1039/d1dt02098f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A novel, efficient and facile protocol for the synthesis of a series of [Ru(NHC)(CO3)(p-cymene)] complexes is reported. This family of Ru-NHC complexes was obtained from imidazol(in)ium tetrafluoroborate or imidazolium hydrogen carbonate salts in moderate to excellent yields, employing sustainable weak base. The ruthenium complexes were successfully utilized in the transfer hydrogenation of ketones as highly active multifunctional catalysts.
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Affiliation(s)
- Xinyuan Ma
- Department of Chemistry and Centre for Sustainable Chemistry Ghent University, Krijgslaan 281, S-3, 9000 Ghent, Belgium.
| | - Sébastien G Guillet
- Department of Chemistry and Centre for Sustainable Chemistry Ghent University, Krijgslaan 281, S-3, 9000 Ghent, Belgium.
| | - Yaxu Liu
- Department of Chemistry and Centre for Sustainable Chemistry Ghent University, Krijgslaan 281, S-3, 9000 Ghent, Belgium.
| | - Catherine S J Cazin
- Department of Chemistry and Centre for Sustainable Chemistry Ghent University, Krijgslaan 281, S-3, 9000 Ghent, Belgium.
| | - Steven P Nolan
- Department of Chemistry and Centre for Sustainable Chemistry Ghent University, Krijgslaan 281, S-3, 9000 Ghent, Belgium.
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9
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Preformed molecular complexes of metals with organoselenium ligands: Syntheses and applications in catalysis. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.213885] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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10
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Arora A, Oswal P, Kumar Rao G, Kumar S, Kumar A. Organoselenium ligands for heterogeneous and nanocatalytic systems: development and applications. Dalton Trans 2021; 50:8628-8656. [PMID: 33954317 DOI: 10.1039/d1dt00082a] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Organoselenium ligands have attracted great attention among researchers during the past two decades. Various homogeneous, heterogeneous and nanocatalytic systems have been designed using such ligands. Although reports on selenium ligated homogeneous catalysts are quite high in number, significant work has also been done on the development of heterogeneous and nanocatalytic systems using organoselenium ligands. A review article, focusing on the utility of organoselenium compounds in the development of catalytic systems, was published in 2012 (A. Kumar, G. K. Rao, F. Saleem and A. K. Singh, Dalton Trans., 2012, 41, 11949). Moreover, it mainly covered the homogeneous catalysts. There are no review articles in the literature on heterogeneous and nanocatalytic systems designed using organoselenium compounds and their applications. Hence, this perspective aims to cover the developments pertaining to the synthetic aspects of such catalytic systems (using organoselenium compounds) and their applications in catalysis of a variety of chemical transformations. Salient features and advantages of organoselenium compounds have also been highlighted to justify the rationale behind their use in catalyst development. Their performance in various chemical transformations [viz. Suzuki-Miyaura coupling, Heck coupling, Sonogashira coupling, O-arylation of phenol, transfer hydrogenation of aldehydes and ketones, aldehyde-alkyne-amine (A3) coupling, hydration of nitriles, conversion of aldehydes to amides, cross-dehydrogenative coupling (CDC), photodegradation of substrates (formic acid, methylene blue), reduction of nitrophenols, electrolysis (hydrogen evolution reaction and oxygen reduction reactions), organocatalysis and dye sensitized solar cells] and relevant aspects of catalytic processes (such as recyclability, substrate scope and green aspects) have been critically analyzed. Future perspectives have also been discussed.
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Affiliation(s)
- Aayushi Arora
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
| | - Preeti Oswal
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
| | - Gyandshwar Kumar Rao
- Department of Chemistry, Amity School of Applied Sciences, Amity University Haryana (AUH), Gurgaon, Haryana 122413, India
| | - Sushil Kumar
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
| | - Arun Kumar
- Department of Chemistry, School of Physical Sciences, Doon University, Dehradun, Uttarakhand 248012, India.
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11
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Medici S, Peana M, Pelucelli A, Zoroddu MA. Rh(I) Complexes in Catalysis: A Five-Year Trend. Molecules 2021; 26:2553. [PMID: 33925725 PMCID: PMC8125654 DOI: 10.3390/molecules26092553] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 11/16/2022] Open
Abstract
Rhodium is one of the most used metals in catalysis both in laboratory reactions and industrial processes. Despite the extensive exploration on "classical" ligands carried out during the past decades in the field of rhodium-catalyzed reactions, such as phosphines, and other common types of ligands including N-heterocyclic carbenes, ferrocenes, cyclopentadienyl anion and pentamethylcyclopentadienyl derivatives, etc., there is still lively research activity on this topic, with considerable efforts being made toward the synthesis of new preformed rhodium catalysts that can be both efficient and selective. Although the "golden age" of homogeneous catalysis might seem over, there is still plenty of room for improvement, especially from the point of view of a more sustainable chemistry. In this review, temporally restricted to the analysis of literature during the past five years (2015-2020), the latest findings and trends in the synthesis and applications of Rh(I) complexes to catalysis will be presented. From the analysis of the most recent literature, it seems clear that rhodium-catalyzed processes still represent a stimulating challenge for the metalloorganic chemist that is far from being over.
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Affiliation(s)
- Serenella Medici
- Department of Chemistry and Pharmacy, University of Sassari, Vienna 2, 07100 Sassari, Italy; (A.P.); (M.A.Z.)
| | - Massimiliano Peana
- Department of Chemistry and Pharmacy, University of Sassari, Vienna 2, 07100 Sassari, Italy; (A.P.); (M.A.Z.)
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12
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Daubit IM, Wortmann S, Siegmund D, Hahn S, Nuernberger P, Metzler‐Nolte N. Unveiling Luminescent Ir I and Rh I N-Heterocyclic Carbene Complexes: Structure, Photophysical Specifics, and Cellular Localization in the Endoplasmic Reticulum. Chemistry 2021; 27:6783-6794. [PMID: 33755263 PMCID: PMC8252781 DOI: 10.1002/chem.202100375] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Indexed: 01/28/2023]
Abstract
Complexes of RhI and IrI of the [M(COD)(NHC)X] type (where M=Rh or Ir, COD=1,5-cyclooctadiene, NHC=N-heterocyclic carbene, and X=halide) have recently shown promising cytotoxic activities against several cancer cell lines. Initial mechanism of action studies provided some knowledge about their interaction with DNA and proteins. However, information about their cellular localization remains scarce owing to luminescence quenching within this complex type. Herein, the synthesis of two rare examples of luminescent RhI and IrI [M(COD)(NHC)I] complexes with 1,8-naphthalimide-based emitting ligands is reported. All new complexes are comprehensively characterized, including with single-crystal X-ray structures. Steric crowding in one derivative leads to two distinct rotamers in solution, which apparently can be distinguished both by pronounced NMR shifts and by their respective spectral and temporal emission signatures. When the photophysical properties of these new complexes are exploited for cellular imaging in HT-29 and PT-45 cancer cell lines, it is demonstrated that the complexes accumulate predominantly in the endoplasmic reticulum, which is an entirely new finding and provides the first insight into the cellular localization of such IrI (NHC) complexes.
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Affiliation(s)
- Isabelle Marie Daubit
- Faculty of Chemistry and BiochemistryInorganic Chemistry I—Bioinorganic ChemistryRuhr-Universität BochumUniversitätsstraße 15044780BochumGermany
| | - Svenja Wortmann
- Institut für Physikalische und Theoretische ChemieUniversität RegensburgUniversitätsstraße 3193053RegensburgGermany
| | - Daniel Siegmund
- Division EnergyFraunhofer UMSICHTOsterfelder Str. 346047OberhausenGermany
| | - Stephan Hahn
- Molecular GI OncologyRuhr-Universität BochumUniversitätsstraße 15044780BochumGermany
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische ChemieUniversität RegensburgUniversitätsstraße 3193053RegensburgGermany
| | - Nils Metzler‐Nolte
- Faculty of Chemistry and BiochemistryInorganic Chemistry I—Bioinorganic ChemistryRuhr-Universität BochumUniversitätsstraße 15044780BochumGermany
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13
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Bal S, Demirci Ö, Şen B, Taslimi P, Aktaş A, Gök Y, Aygün M, Gülçin İ. Synthesis, characterization, crystal structure, α-glycosidase, and acetylcholinesterase inhibitory properties of 1,3-disubstituted benzimidazolium salts. Arch Pharm (Weinheim) 2021; 354:e2000422. [PMID: 33427318 DOI: 10.1002/ardp.202000422] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 10/22/2022]
Abstract
Chloro-/fluorobenzyl-substituted benzimidazolium salts were synthesized from the reaction of 4-fluorobenzyl/2-chloro-4-fluorobenzyl-substituted benzimidazole and chlorinated aromatic hydrocarbons. They were characterized using various spectroscopic techniques (Fourier-transform infrared and nuclear magnetic resonance) and elemental analysis. In addition, the crystal structures of the complexes 1a -d and 2b were determined by single-crystal X-ray diffraction methods. These compounds were crystallized in the triclinic crystal system with a P-1 space group. The crystal packing of all complexes is dominated by O-H⋯Cl hydrogen bonds, which link the water molecules and chloride anions, forming a chloride-water tetrameric cluster. These synthesized salts were found to be effective inhibitors for α-glycosidase and acetylcholinesterase (AChE), with Ki values ranging from 45.77 ± 6.83 to 102.61 ± 11.56 µM for α-glycosidase and 0.94 ± 0.14 to 10.24 ± 1.58 µM for AChE. AChE converts acetylcholine into choline and acetic acid, thus causing the return of a cholinergic neuron to its resting state. Discovering AChE and α-glycosidase inhibitors is one of the important ways to develop new drugs for the treatment of Alzheimer's disease and diabetes.
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Affiliation(s)
- Selma Bal
- Department of Chemistry, Faculty of Science and Arts, University of Kahramanmaraş Sütçü Imam, Kahramanmaraş, Turkey
| | - Özlem Demirci
- Department of Chemistry, Faculty of Science and Arts, Inonu University, Malatya, Turkey
| | - Betül Şen
- Department of Physics, Faculty of Science, Dokuz Eylül University, İzmir, Turkey
| | - Parham Taslimi
- Department of Biotechnology, Faculty of Science, Bartin University, Bartin, Turkey
| | - Aydın Aktaş
- Department of Chemistry, Faculty of Science and Arts, Inonu University, Malatya, Turkey.,Vocational School of Health Service, Faculty of Science, Inonu University, Malatya, Turkey
| | - Yetkin Gök
- Department of Chemistry, Faculty of Science and Arts, Inonu University, Malatya, Turkey
| | - Muhittin Aygün
- Department of Physics, Faculty of Science, Dokuz Eylül University, İzmir, Turkey
| | - İlhami Gülçin
- Department of Chemistry, Faculty of Science, Atatürk University, Erzurum, Turkey
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14
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Jamil MSS, Endot NA. Influence of Fluorine Substituents on the Electronic Properties of Selenium- N-Heterocyclic Carbene Compounds. Molecules 2020; 25:molecules25215161. [PMID: 33171911 PMCID: PMC7664287 DOI: 10.3390/molecules25215161] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 12/26/2022] Open
Abstract
N-heterocyclic carbenes (NHCs) are common ancillary ligands in organometallic compounds that are used to alter the electronic and steric properties of a metal centre. To date, various NHCs have been synthesised with different electronic properties, which can be done by modifying the backbone or changing the nitrogen substituents group. This study describes a systematic modification of NHCs by the inclusion of fluorine substituents and examines the use of selenium-NHC compounds to measure the π-accepting ability of these fluorinated NHC ligands. Evaluation of the 77Se NMR chemical shifts of the selenium adducts reveals that fluorinated NHCs have higher chemical shifts than the non-fluorinated counterparts, IMes and IPh. Higher 77Se NMR chemical shifts values indicate a stronger π-accepting ability of the NHC ligands. The findings of this study suggest that the presence of fluorine atoms has increased the π-accepting ability of the corresponding NHC ligands. This work supports the advantage of the 77Se NMR chemical shifts of selenium-NHC compounds for assessing the influence of fluorine substituents on NHC ligands.
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Affiliation(s)
- Mohamad Shazwan Shah Jamil
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor Bahru 81310 UTM, Johor, Malaysia
- Correspondence: (M.S.S.J.); (N.A.E.)
| | - Nor Azam Endot
- Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Serdang 43400 UPM, Selangor, Malaysia
- Correspondence: (M.S.S.J.); (N.A.E.)
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15
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Rufino-Felipe E, Valdés H, Germán-Acacio JM, Reyes-Márquez V, Morales-Morales D. Fluorinated N-Heterocyclic carbene complexes. Applications in catalysis. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121364] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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16
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Precious metal N-heterocyclic carbene-carbaboranyl complexes: Cytotoxic and selective compounds for the treatment of cancer. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2019.121062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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