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Jamshidi M, Bouheriche J, Gardner JM. Photoluminescent copper(I) iodide alkylpyridine thin films as sensors for volatile halogenated compounds. Front Chem 2023; 11:1330227. [PMID: 38146426 PMCID: PMC10749296 DOI: 10.3389/fchem.2023.1330227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/01/2023] [Indexed: 12/27/2023] Open
Abstract
The paper presents the fabrication and characterization of [CuI(L)]n thin films, where L represents various alkylpyridine ligands including 4-methylpyridine, 3-methylpyridine, 2-methylpyridine, 4-tbutylpyridine, 3,4-dimethylpyridine, and 3,5-dimethylpyridine. The thin films were synthesized by exposing the corresponding ligands to CuI thin films through vapor deposition. The coordination reactions occurring on the films were investigated using PXRD and time-dependent photoluminescence spectroscopy, and a comparison was made between the structures of the thin films and the corresponding powder phases. The films showed primarly blue emission (λem = 457-515 nm) and polymeric structures with excited state lifetimes ranging from 0.6 to 5.5 μs. Significantly, the studied compounds exhibited fast reversible luminescence quenching when exposed to vapors of dichloromethane and dibromomethane (15 and 30 min respectively), and the luminescence was restored upon re-exposure to the alkylpyridine ligand (after 20 min). These findings indicate that these thin films hold promise for applications as sensors (with sensitive and reversible detection capability) for volatile halogen-based compounds (VHC).
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Affiliation(s)
| | | | - James M. Gardner
- Department of Chemistry, Division of Applied Physical Chemistry, KTH Royal Institute of Technology, Stockholm, Sweden
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2
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Wang D, Hu W, Liu C, Huang J, Zhang X. Electronic Tuning of Photoexcited Dynamics in Heteroleptic Cu(I) Complex Photosensitizers. J Phys Chem Lett 2023; 14:10137-10144. [PMID: 37922426 DOI: 10.1021/acs.jpclett.3c02503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Photoexcited dynamics of heteroleptic Cu(I) complexes as noble-metal-free photosensitizers are closely intertwined with the nature of their ligands. By utilizing ultrafast optical and X-ray transient absorption spectroscopies, we characterized a new set of heteroleptic Cu(I) complexes [Cu(PPh3)2(BPyR)]+ (R = CH3, H, Br to COOCH3), with an increase in the electron-withdrawing ability of the functional group (R). We found that after the transient photooxidation of Cu(I) to Cu(II), the increasing electron-withdrawing ability of R barely affects the internal conversion (IC) (e.g., Jahn-taller (JT) distortion) between singlet MLCT states. However, it does accelerate the dynamics of intersystem crossing (ISC) between singlet and triplet MLCT states and the subsequent decay from the triplet MLCT state to the ground state. The associated lifetime constants are reduced by up to 300%. Our understanding of the photoexcited dynamics in heteroleptic Cu(I) complexes through ligand electronic tuning provides valuable insight into the rational design of efficient Cu(I) complex photosensitizers.
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Affiliation(s)
- Denan Wang
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
| | - Wenhui Hu
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
| | - Cunming Liu
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60349, United States
| | - Jier Huang
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
- Department of Chemistry and Schiller Institute for Integrated Science and Society, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Xiaoyi Zhang
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60349, United States
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3
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Woo S, Jung H, Yoon Y. Real-Time UV/VIS Spectroscopy to Observe Photocatalytic Degradation. Catalysts 2023. [DOI: 10.3390/catal13040683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
In this work, we have developed a real-time UV/VIS spectroscopy method using a broadband Xenon Arc lamp to detect photocatalytic reactions in real time. A CMOS camera was used instead of an output slit to capture all spectral information simultaneously, which can enable a real-time detection of the UV/VIS absorption of the analytes within a single frame of the camera. To verify real-time spectroscopy, a wavelength calibration process was performed using three laser line filters and a didymium glass filter sample. To demonstrate that this real-time spectroscopic setup can be used for rapid measurements, MB samples were used to observe the real-time photocatalytic degradation of MB by TiO2 nanoparticles. For real-time measurement, four samples with different TiO2 nanoparticle quantities showed different photocatalytic degradation mechanisms. By plotting the spectra every 20 ms, the series of spectra clearly showed the degradation of MB in real time.
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4
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Beaudelot J, Oger S, Peruško S, Phan TA, Teunens T, Moucheron C, Evano G. Photoactive Copper Complexes: Properties and Applications. Chem Rev 2022; 122:16365-16609. [PMID: 36350324 DOI: 10.1021/acs.chemrev.2c00033] [Citation(s) in RCA: 65] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Photocatalyzed and photosensitized chemical processes have seen growing interest recently and have become among the most active areas of chemical research, notably due to their applications in fields such as medicine, chemical synthesis, material science or environmental chemistry. Among all homogeneous catalytic systems reported to date, photoactive copper(I) complexes have been shown to be especially attractive, not only as alternative to noble metal complexes, and have been extensively studied and utilized recently. They are at the core of this review article which is divided into two main sections. The first one focuses on an exhaustive and comprehensive overview of the structural, photophysical and electrochemical properties of mononuclear copper(I) complexes, typical examples highlighting the most critical structural parameters and their impact on the properties being presented to enlighten future design of photoactive copper(I) complexes. The second section is devoted to their main areas of application (photoredox catalysis of organic reactions and polymerization, hydrogen production, photoreduction of carbon dioxide and dye-sensitized solar cells), illustrating their progression from early systems to the current state-of-the-art and showcasing how some limitations of photoactive copper(I) complexes can be overcome with their high versatility.
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Affiliation(s)
- Jérôme Beaudelot
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium.,Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Samuel Oger
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium
| | - Stefano Peruško
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium.,Organic Synthesis Division, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020Antwerp, Belgium
| | - Tuan-Anh Phan
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Titouan Teunens
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium.,Laboratoire de Chimie des Matériaux Nouveaux, Université de Mons, Place du Parc 20, 7000Mons, Belgium
| | - Cécile Moucheron
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Gwilherm Evano
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium
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5
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Towards Optimized Photoluminescent Copper(I) Phenanthroline-Functionalized Complexes: Control of the Photophysics by Symmetry-Breaking and Spin–Orbit Coupling. MATERIALS 2022; 15:ma15155222. [PMID: 35955157 PMCID: PMC9369739 DOI: 10.3390/ma15155222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 11/17/2022]
Abstract
The electronic and structural alterations induced by the functionalization of the 1,10-phenanthroline (phen) ligand in [Cu(I) (phen-R2)2]+ complexes (R=H, CH3, tertio-butyl, alkyl-linkers) and their consequences on the luminescence properties and thermally activated delay fluorescence (TADF) activity are investigated using the density functional theory (DFT) and its time-dependent (TD) extension. It is shown that highly symmetric molecules with several potentially emissive nearly-degenerate conformers are not promising because of low S1/S0 oscillator strengths together with limited or no S1/T1 spin–orbit coupling (SOC). Furthermore, steric hindrance, which prevents the flattening of the complex upon irradiation, is a factor of instability. Alternatively, linking the phenanthroline ligands offers the possibility to block the flattening while maintaining remarkable photophysical properties. We propose here two promising complexes, with appropriate symmetry and enough rigidity to warrant stability in standard solvents. This original study paves the way for the supramolecular design of new emissive devices.
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6
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Rentschler M, Boden PJ, Argüello Cordero MA, Steiger ST, Schmid MA, Yang Y, Niedner-Schatteburg G, Karnahl M, Lochbrunner S, Tschierlei S. Unexpected Boost in Activity of a Cu(I) Photosensitizer by Stabilizing a Transient Excited State. Inorg Chem 2022; 61:12249-12261. [PMID: 35877171 DOI: 10.1021/acs.inorgchem.2c01468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we present a slight but surprisingly successful structural modification of the previously reported heteroleptic Cu(I) photosensitizer Cubiipo ([(xantphos)Cu(biipo)]PF6; biipo = 16H-benzo-[4',5']-isoquinolino-[2',1':1,2]-imidazo-[4,5-f]-[1,10]-phenanthrolin-16-one). As a key feature, biipo bears a naphthalimide unit at the back, which is directly fused to a phenanthroline moiety to extend the conjugated π-system. This ligand was now altered to include two additional methyl groups at the 2,9-positions at the phenanthroline scaffold. Comparing the novel Cudmbiipo complex to its predecessor, ultrafast transient absorption spectroscopy reveals the efficient suppression of a major deactivation pathway by stabilization of a transient triplet state. Furthermore, quantitative measurements of singlet oxygen evolution in solution confirmed that a larger fraction of the excited-state population is transferred to the photocatalytically active ligand-centered triplet 3LC state with a much longer lifetime of ∼30 μs compared to Cubiipo (2.6 μs). In addition, Cudmbiipo was compared with the well-established reference complex Cubcp ([(xantphos)Cu(bathocuproine)]PF6) in terms of its photophysical and photocatalytic properties by applying time-resolved femto- and nanosecond absorption, step-scan Fourier transform infrared (FTIR), and emission spectroscopies. Superior light-harvesting properties and a greatly enhanced excited-state lifetime with respect to Cubcp enable Cudmbiipo to be more active in exemplary photocatalytic applications, i.e., in the formation of singlet oxygen and the isomerization of (E)-stilbene.
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Affiliation(s)
- Martin Rentschler
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Rebenring 31, 38106 Braunschweig, Germany
| | - Pit Jean Boden
- Chemistry Department and State Research Center Optimas, TU Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany
| | - Miguel A Argüello Cordero
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, Albert-Einstein-Straße 23, 18051 Rostock, Germany
| | - Sophie Theres Steiger
- Chemistry Department and State Research Center Optimas, TU Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany
| | - Marie-Ann Schmid
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Rebenring 31, 38106 Braunschweig, Germany
| | - Yingya Yang
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Rebenring 31, 38106 Braunschweig, Germany
| | - Gereon Niedner-Schatteburg
- Chemistry Department and State Research Center Optimas, TU Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany
| | - Michael Karnahl
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Rebenring 31, 38106 Braunschweig, Germany
| | - Stefan Lochbrunner
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, Albert-Einstein-Straße 23, 18051 Rostock, Germany
| | - Stefanie Tschierlei
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Rebenring 31, 38106 Braunschweig, Germany
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7
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Orange-red emissive Cu(I) complexes bearing Schiff base ligands: Synthesis, structures, and photophysical properties. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.132180] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Argüello Cordero MA, Boden PJ, Rentschler M, Di Martino-Fumo P, Frey W, Yang Y, Gerhards M, Karnahl M, Lochbrunner S, Tschierlei S. Comprehensive Picture of the Excited State Dynamics of Cu(I)- and Ru(II)-Based Photosensitizers with Long-Lived Triplet States. Inorg Chem 2021; 61:214-226. [PMID: 34908410 DOI: 10.1021/acs.inorgchem.1c02771] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ru(II)- and Cu(I)-based photosensitizers featuring the recently developed biipo ligand (16H-benzo-[4',5']-isoquinolino-[2',1',:1,2]-imidazo-[4,5-f]-[1,10]-phenanthrolin-16-one) were comprehensively investigated by X-ray crystallography, electrochemistry, and especially several time-resolved spectroscopic methods covering all time scales from femto- to milliseconds. The analysis of the experimental results is supported by density functional theory (DFT) calculations. The biipo ligand consists of a coordinating 1,10-phenanthroline moiety fused with a 1,8-naphthalimide unit, which results in an extended π-system with an incorporated electron acceptor moiety. In a previous study, it was shown that this ligand enabled a Ru(II) complex that is an efficient singlet oxygen producer and of potential use for other light-driven applications due to its long emission lifetime. The goal of our here presented research is to provide a full spectroscopic picture of the processes that follow optical excitation. Interestingly, the Ru(II) and Cu(I) complexes differ in their characteristics even though the lowest electronically excited states involve in both cases the biipo ligand. The combined spectroscopic results indicate that an emissive 3MLCT state and a rather dark 3LC state are populated, each to some extent. For the Cu(I) complex, most of the excited population ends up in the 3LC state with an extraordinary lifetime of 439 μs in the solid state at 20 K, while a significant population of the 3MLCT state causes luminescence for the Ru(II) complex. Hence, there is a balance between these two states, which can be tuned by altering the metal center or even by thermal energy, as suggested by the temperature-dependent experiments.
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Affiliation(s)
- Miguel A Argüello Cordero
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, 18051 Rostock, Germany
| | - Pit Jean Boden
- Chemistry Department and Research Center Optimas, TU Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany
| | - Martin Rentschler
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany.,Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
| | - Patrick Di Martino-Fumo
- Chemistry Department and Research Center Optimas, TU Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany
| | - Wolfgang Frey
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Yingya Yang
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
| | - Markus Gerhards
- Chemistry Department and Research Center Optimas, TU Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany
| | - Michael Karnahl
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany.,Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
| | - Stefan Lochbrunner
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, 18051 Rostock, Germany
| | - Stefanie Tschierlei
- Department of Energy Conversion, Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
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9
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Grupe M, Boden P, Di Martino‐Fumo P, Gui X, Bruschi C, Israil R, Schmitt M, Nieger M, Gerhards M, Klopper W, Riehn C, Bizzarri C, Diller R. Time-Resolved Spectroscopy and Electronic Structure of Mono-and Dinuclear Pyridyl-Triazole/DPEPhos-Based Cu(I) Complexes. Chemistry 2021; 27:15251-15270. [PMID: 34550622 PMCID: PMC8597052 DOI: 10.1002/chem.202102760] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Indexed: 12/20/2022]
Abstract
Chemical and spectroscopic characterization of the mononuclear photosensitizers [(DPEPhos)Cu(I)(MPyrT)]0/+ (CuL, CuLH) and their dinuclear analogues (Cu2 L', Cu2 L'H2 ), backed by (TD)DFT and high-level GW-Bethe-Salpeter equation calculations, exemplifies the complex influence of charge, nuclearity and structural flexibility on UV-induced photophysical pathways. Ultrafast transient absorption and step-scan FTIR spectroscopy reveal flattening distortion in the triplet state of CuLH as controlled by charge, which also appears to have a large impact on the symmetry of the long-lived triplet states in Cu2 L' and Cu2 L'H2 . Time-resolved luminescence spectroscopy (solid state), supported by transient photodissociation spectroscopy (gas phase), confirm a lifetime of some tens of μs for the respective triplet states, as well as the energetics of thermally activated delayed luminescence, both being essential parameters for application of these materials based on earth-abundant copper in photocatalysis and luminescent devices.
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Affiliation(s)
- Merten Grupe
- Department of PhysicsTU KaiserslauternErwin-Schrödinger-Straße 4667663KaiserslauternGermany
| | - Pit Boden
- Department of ChemistryTU KaiserslauternErwin-Schrödinger-Straße 5267663KaiserslauternGermany
| | - Patrick Di Martino‐Fumo
- Department of ChemistryTU KaiserslauternErwin-Schrödinger-Straße 5267663KaiserslauternGermany
| | - Xin Gui
- Institute of Physical ChemistryKarlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 276131KarlsruheGermany
| | - Cecilia Bruschi
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
| | - Roumany Israil
- Department of ChemistryTU KaiserslauternErwin-Schrödinger-Straße 5267663KaiserslauternGermany
| | - Marcel Schmitt
- Department of ChemistryTU KaiserslauternErwin-Schrödinger-Straße 5267663KaiserslauternGermany
| | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiA.I. Virtasen aukio 100014HelsinkiFinland
| | - Markus Gerhards
- Department of ChemistryTU KaiserslauternErwin-Schrödinger-Straße 5267663KaiserslauternGermany
- Research Center OPTIMASErwin-Schrödinger-Straße 4667663KaiserslauternGermany
| | - Wim Klopper
- Institute of Physical ChemistryKarlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 276131KarlsruheGermany
| | - Christoph Riehn
- Department of ChemistryTU KaiserslauternErwin-Schrödinger-Straße 5267663KaiserslauternGermany
- Research Center OPTIMASErwin-Schrödinger-Straße 4667663KaiserslauternGermany
| | - Claudia Bizzarri
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
| | - Rolf Diller
- Department of PhysicsTU KaiserslauternErwin-Schrödinger-Straße 4667663KaiserslauternGermany
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10
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Hassan Z, Bräse S. Metal-to-Metal Distance Modulation by Ligand Design: A Case Study of Structure-Property Correlation in Planar Chiral Cyclophanyl Metal Complexes. Chemistry 2021; 27:15020-15026. [PMID: 34449116 PMCID: PMC8597128 DOI: 10.1002/chem.202102336] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Indexed: 11/25/2022]
Abstract
Multinuclear metal complexes have seen tremendous progress in synthetic advances, their versatile structural features, and emerging applications. Here, we conceptualize Metal-to-Metal distance modulation in cyclophanyl metal complexes by bridging ligand design employing the co-facially stacked cyclophanyl-derived pseudo-geminal, -ortho, -meta, and -para constitutional isomers grafted with N-, O-, and P- containing chelates that allow the installation of diverse (hetero)metallic moieties in a distance-defined and spatially-oriented relation to one another. Metal-to-Metal distance modulation and innate transannular "through-space" π-π electronic interactions via the co-facially stacked benzene rings in cyclophanyl-derived complexes as well as their specific stereochemical structural features (element of planar chirality) are crucial factors that contribute to the tuning of structure-property relationships, which stand at the very center from the perspective of cooperative effects in catalysis as well as emerging material applications.
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Affiliation(s)
- Zahid Hassan
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
| | - Stefan Bräse
- Institute of Organic Chemistry (IOC)Karlsruhe Institute of Technology (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
- Institute of Biological and Chemical SystemsFunctional Molecular Systems (IBCS-FMS)Karlsruhe Institute of Technology (KIT)Hermann-von-Helmholtz-Platz 176344Eggenstein-LeopoldshafenGermany
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11
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Ndugire W, Yan M. Synthesis and solution isomerization of water-soluble Au 9 nanoclusters prepared by nuclearity conversion of [Au 11(PPh 3) 8Cl 2]Cl. NANOSCALE 2021; 13:16809-16817. [PMID: 34605842 PMCID: PMC8545225 DOI: 10.1039/d1nr04401j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Water-soluble gold nanoclusters (AuNCs) are popular in biomedical applications such as bioimaging, labelling, drug delivery, and biosensing. Despite their widespread applications, the synthesis of water-soluble phosphine-capped AuNCs is not as straightforward as their organic-soluble equivalents. Organic soluble phosphine-passivated [Au9(L)8]3+ are 6-electron closed-shell AuNCs that are generally prepared via the reduction of a phosphine-Au(I) complex by NaBH4. A similar approach attempted for the water-soluble ligand triphenylphosphine monosulfonate (TPPMS) using [AuTPPMS]Cl resulted in a mixture of cluster sizes that required gel electrophoresis or fractional precipitation to isolate the Au9 product. In this work, we report the synthesis of water-soluble [Au9(L)8]3+ nanoclusters in high yield through the biphasic ligand exchange of [Au11(PPh3)8Cl2]Cl with water-soluble phosphines such as TPPMS and 4-(diphenylphosphino)benzoic acid (DPPBA). The small molecule byproducts can be completely removed by size-based separation methods, like size exclusion chromatography or dialysis, as confirmed by 31P and 1H nuclear magnetic resonance (NMR) as well as diffusion ordered spectroscopy (DOSY). Furthermore, [Au9(DPPBA)8]Cl3 underwent a visible pH- and temperature-induced isomerization in ethanol between the 'crown' and 'butterfly' isomers of [Au9(L)8]3+ which has not been previously reported. Cytotoxicity evaluation of these water-soluble nanoclusters gave CC50 values of 36 μg mL-1 and 70 μg mL-1 against A549 human alveolar epithelial cells, and 30 μg mL-1 and 40 μg mL-1 against NIH/3T3 mouse fibroblast cells for [Au9(TPPMS)8]Cl3 and [Au9(DPPBA)8]Cl3, respectively. For comparison, auranofin, an FDA-approved gold drug, is more than an order of magnitude more toxic with a CC50 value of 7.7 μg mL-1 against A549 cells.
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Affiliation(s)
- William Ndugire
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854, USA.
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854, USA.
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12
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Lüdtke N, Föller J, Marian CM. Understanding the luminescence properties of Cu(i) complexes: a quantum chemical perusal. Phys Chem Chem Phys 2020; 22:23530-23544. [PMID: 33074271 DOI: 10.1039/d0cp04654j] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Electronic structures and excited-state properties of Cu(i) complexes with varying coordination numbers have been investigated by means of advanced quantum chemical methods. The computational protocol employs density functional-based methods for geometry optimizations and vibrational analyses including solvent effects through continuum models. Excitation energies, spin-orbit couplings and luminescence properties are evaluated using multireference configuration interaction methods. Rate constants of spin-allowed and spin-forbidden transitions have been determined according to the Fermi golden rule. The computational results for the 4-coordinate (DPEPhos)Cu(PyrTet), the 3-coordinate [IPr-Cu-Py2]+, and the linear CAACMe2-Cu-Cl complexes agree well with experimental absorption and emission wavelengths, intersystem crossing (ISC) time constants, and radiative lifetimes in liquid solution. Spectral shifts on the ligand-to-ligand charge transfer (LLCT) and metal-to-ligand charge transfer (MLCT) transitions caused by the polarity of the environment are well represented by the continuum models whereas the shifts caused by pseudo-Jahn-Teller distortions in the MLCT states are too pronounced in comparison to solid-state data. Systematic variation of the ligands in linear Cu(i) carbene complexes shows that only those complexes with S1 and T1 states of LLCT character possess sufficiently small singlet-triplet energy gaps ΔEST to enable thermally activated delayed fluorescence (TADF). Complexes whose S1 and T1 wavefunctions are dominated by MLCT excitations tend to emit phosphorescence instead. Unlike the situation in metal-free TADF emitters, the presence of low-lying locally excited triplet states does not promote ISC. These states rather hold the danger of trapping the excitation with nonradiative deactivation being the major deactivation channel.
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Affiliation(s)
- Nora Lüdtke
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
| | - Jelena Föller
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
| | - Christel M Marian
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
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