1
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Wu S, Stanley PM, Deger SN, Hussain MZ, Jentys A, Warnan J. Photochargeable Mn-Based Metal-Organic Framework and Decoupled Photocatalysis. Angew Chem Int Ed Engl 2024:e202406385. [PMID: 39074974 DOI: 10.1002/anie.202406385] [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: 04/03/2024] [Indexed: 07/31/2024]
Abstract
Designing multifunctional materials that mimic the light-dark decoupling of natural photosynthesis is a key challenge in the field of energy conversion. Herein, we introduce MnBr-253, a precious metal-free metal-organic framework (MOF) built on Al nodes, bipyridine linkers and MnBr(CO)3(bipyridine) complexes. Upon irradiation, MnBr-253 colloids demonstrate an electron photocharging capacity of ~42 C ⋅ g-1 MOF, with state-of-the-art photocharging rate (1.28 C ⋅ s-1 ⋅ g-1 MOF) and incident photon-to-electron conversion efficiency of ~9.4 % at 450 nm. Spectroscopic and computational studies support effective electron accumulation at the Mn complex while high porosity and Mn loading account for the notable electron storage performance. The charged MnBr-253 powders were successfully applied for hydrogen evolution under dark conditions thus emulating the light-decoupled reactivity of photosynthesis.
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Affiliation(s)
- Shufan Wu
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry, and Catalysis Research Center (CRC), TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Philip M Stanley
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry, and Catalysis Research Center (CRC), TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Simon N Deger
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry, and Catalysis Research Center (CRC), TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Mian Zahid Hussain
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry, and Catalysis Research Center (CRC), TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Andreas Jentys
- Chair of Industrial Chemistry and Heterogenous Catalysis, Department of Chemistry, and Catalysis Research Center (CRC), TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Julien Warnan
- Chair of Inorganic and Metal-Organic Chemistry, Department of Chemistry, and Catalysis Research Center (CRC), TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
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2
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Maity B, Shoji M, Luo F, Nakane T, Abe S, Owada S, Kang J, Tono K, Tanaka R, Pham TT, Kojima M, Hishikawa Y, Tanaka J, Tian J, Nagama M, Suzuki T, Noya H, Nakasuji Y, Asanuma A, Yao X, Iwata S, Shigeta Y, Nango E, Ueno T. Real-time observation of a metal complex-driven reaction intermediate using a porous protein crystal and serial femtosecond crystallography. Nat Commun 2024; 15:5518. [PMID: 38951539 PMCID: PMC11217357 DOI: 10.1038/s41467-024-49814-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 06/14/2024] [Indexed: 07/03/2024] Open
Abstract
Determining short-lived intermediate structures in chemical reactions is challenging. Although ultrafast spectroscopic methods can detect the formation of transient intermediates, real-space structures cannot be determined directly from such studies. Time-resolved serial femtosecond crystallography (TR-SFX) has recently proven to be a powerful method for capturing molecular changes in proteins on femtosecond timescales. However, the methodology has been mostly applied to natural proteins/enzymes and limited to reactions promoted by synthetic molecules due to structure determination challenges. This work demonstrates the applicability of TR-SFX for investigations of chemical reaction mechanisms of synthetic metal complexes. We fix a light-induced CO-releasing Mn(CO)3 reaction center in porous hen egg white lysozyme (HEWL) microcrystals. By controlling light exposure and time, we capture the real-time formation of Mn-carbonyl intermediates during the CO release reaction. The asymmetric protein environment is found to influence the order of CO release. The experimentally-observed reaction path agrees with quantum mechanical calculations. Therefore, our demonstration offers a new approach to visualize atomic-level reactions of small molecules using TR-SFX with real-space structure determination. This advance holds the potential to facilitate design of artificial metalloenzymes with precise mechanisms, empowering design, control and development of innovative reactions.
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Affiliation(s)
- Basudev Maity
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan.
| | - Mitsuo Shoji
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Fangjia Luo
- JASRI, 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
| | - Takanori Nakane
- Institute of Protein Research, Osaka University, Osaka, Japan
| | - Satoshi Abe
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Shigeki Owada
- JASRI, 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
- RIKEN SPring-8 Center, Hyogo, 679-5148, Japan
| | | | - Kensuke Tono
- JASRI, 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
- RIKEN SPring-8 Center, Hyogo, 679-5148, Japan
| | - Rie Tanaka
- RIKEN SPring-8 Center, Hyogo, 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Thuc Toan Pham
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Mariko Kojima
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Yuki Hishikawa
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Junko Tanaka
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Jiaxin Tian
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Misaki Nagama
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Taiga Suzuki
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Hiroki Noya
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Yuto Nakasuji
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Asuka Asanuma
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - Xinchen Yao
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan
| | - So Iwata
- RIKEN SPring-8 Center, Hyogo, 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yasuteru Shigeta
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
| | - Eriko Nango
- RIKEN SPring-8 Center, Hyogo, 679-5148, Japan.
- Tohoku University. Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Japan.
| | - Takafumi Ueno
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan.
- Research Center for Autonomous Systems Materialogy (ASMat), Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Japan.
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3
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Jay RM, Coates MR, Zhao H, Winghart MO, Han P, Wang RP, Harich J, Banerjee A, Wikmark H, Fondell M, Nibbering ETJ, Odelius M, Huse N, Wernet P. Photochemical Formation and Electronic Structure of an Alkane σ-Complex from Time-Resolved Optical and X-ray Absorption Spectroscopy. J Am Chem Soc 2024; 146:14000-14011. [PMID: 38713061 PMCID: PMC11117182 DOI: 10.1021/jacs.4c02077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/29/2024] [Accepted: 04/30/2024] [Indexed: 05/08/2024]
Abstract
C-H bond activation reactions with transition metals typically proceed via the formation of alkane σ-complexes, where an alkane C-H σ-bond binds to the metal. Due to the weak nature of metal-alkane bonds, σ-complexes are challenging to characterize experimentally. Here, we establish the complete pathways of photochemical formation of the model σ-complex Cr(CO)5-alkane from Cr(CO)6 in octane solution and characterize the nature of its metal-ligand bonding interactions. Using femtosecond optical absorption spectroscopy, we find photoinduced CO dissociation from Cr(CO)6 to occur within the 100 fs time resolution of the experiment. Rapid geminate recombination by a fraction of molecules is found to occur with a time constant of 150 fs. The formation of bare Cr(CO)5 in its singlet ground state is followed by complexation of an octane molecule from solution with a time constant of 8.2 ps. Picosecond X-ray absorption spectroscopy at the Cr L-edge and O K-edge provides unique information on the electronic structure of the Cr(CO)5-alkane σ-complex from both the metal and ligand perspectives. Based on clear experimental observables, we find substantial destabilization of the lowest unoccupied molecular orbital upon coordination of the C-H bond to the undercoordinated Cr center in the Cr(CO)5-alkane σ-complex, and we define this as a general, orbital-based descriptor of the metal-alkane bond. Our study demonstrates the value of combining optical and X-ray spectroscopic methods as complementary tools to study the stability and reactivity of alkane σ-complexes in their role as the decisive intermediates in C-H bond activation reactions.
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Affiliation(s)
- Raphael M. Jay
- Department
of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
| | - Michael R. Coates
- Department
of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden
| | - Huan Zhao
- Center
for Free-Electron Laser Science, Department of Physics, University of Hamburg, 22761 Hamburg, Germany
| | - Marc-Oliver Winghart
- Max
Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin, Germany
| | - Peng Han
- Max
Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin, Germany
| | - Ru-Pan Wang
- Center
for Free-Electron Laser Science, Department of Physics, University of Hamburg, 22761 Hamburg, Germany
| | - Jessica Harich
- Center
for Free-Electron Laser Science, Department of Physics, University of Hamburg, 22761 Hamburg, Germany
| | - Ambar Banerjee
- Department
of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
| | - Hampus Wikmark
- Department
of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
| | - Mattis Fondell
- Institute
for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und
Energie GmbH, 12489 Berlin, Germany
| | - Erik T. J. Nibbering
- Max
Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin, Germany
| | - Michael Odelius
- Department
of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden
| | - Nils Huse
- Center
for Free-Electron Laser Science, Department of Physics, University of Hamburg, 22761 Hamburg, Germany
| | - Philippe Wernet
- Department
of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
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4
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Palominos F, Mella P, Guajardo K, Günther G, Vega A, Pizarro N. Photoinduced behaviour of N,N-bidentate manganese(I) and rhenium(I) tricarbonyl complexes for singlet oxygen generation and CO release. Photochem Photobiol Sci 2024; 23:119-132. [PMID: 38082202 DOI: 10.1007/s43630-023-00507-0] [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: 08/16/2023] [Accepted: 11/07/2023] [Indexed: 02/02/2024]
Abstract
The combined action of singlet oxygen (1O2) and photoinduced carbon monoxide (CO) released by tricarbonyl metal complexes is a promising synergic treatment against multi-resistant bacterial infections. In this work, we explore the use of a polydentate ligand (bpm = 2,2-bipyrimidine) that offers the opportunity to accommodate two metal centers exhibiting both singlet oxygen generation and carbon monoxide releasing properties in a single molecule. A series of monometallic ([(bpm)M(CO)3Br]; M = Mn, Re) and homo or hetero bimetallic ([Br(CO)3M(bpm)M'(CO)3Br]; M = Mn, Re) compounds were synthesized in moderate to good yields by modulating the metal precursor or the stoichiometry, also the syn:anti isomers ratio for the bimetallic complexes was dependent on the experimental conditions used. DFT modelling shows the anti-isomer is more stable than the syn-isomer by less than 8 kJ mol-1, which is consistent with those experimentally observed in terms of majority product and the effect of experimental conditions over the anti-syn ratio. The HOMO-LUMO gap is lower for the mono and bimetallic rhenium(I) compounds compared to the values for the manganese(I) analogues, while the heterometallic complex shows intermediate values for the anti-isomer. The photophysical characterization shows typical absorption and emission bands with MLCT character. In addition, CO-release and 1O2 generation quantum yields were evaluated for the monometallic Mnbpm and Rebpm homologues and compared with values obtained for the homo- and hetero-bimetallic complexes. Interestingly the replacement of a Mn(CO)3Br moiety in MnbpmMn by a Re(CO)3Br one makes the heterometallic MnbpmRe molecule a molecular oxygen sensitizer and partially retaining its carbon monoxide releasing ability.
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Affiliation(s)
- Franco Palominos
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Viña del Mar, Chile
- Programa de Doctorado en Fisicoquímica Molecular, Universidad Andrés Bello, Santiago, Chile
| | - Pablo Mella
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Viña del Mar, Chile
| | - Kevin Guajardo
- Facultad de Ciencias de la Vida, Carrera de Ingeniería en Biotecnología, Universidad Andres Bello, Viña del Mar, Chile
| | - Germán Günther
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Andrés Vega
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Viña del Mar, Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Santiago, Chile
| | - Nancy Pizarro
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Viña del Mar, Chile.
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5
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Seth R, Singh A. Rational design of co-ordination compounds in combination of bipyridine type of ligands and group 7 metal (M = Mn, Re) for photoCORM: a DFT study. J Mol Model 2023; 29:306. [PMID: 37676553 DOI: 10.1007/s00894-023-05712-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 08/29/2023] [Indexed: 09/08/2023]
Abstract
CONTEXT A large number of manganese and rhenium tricarbonyl complexes are known in literature along with various applications in different fields. CO-releasing molecules (CORMs) got recent research attention because CO can act as a prodrug for different diseases. CORMs offer the promising prospect of a safe and controllable amount of CO release. In this research work, we have explored the electronic properties of compounds such as bipyridine-related [Mn(CO)3] and [Re(CO)3] and we have compared the electronic properties of both manganese and rhenium tricarbonyl complexes in the light of carbon monoxide releasing tendency. The chosen Mn and Re metals have enough possibility to vary or play with ligands and design a new and novel CORM molecule. In this context, we have taken a range of 4,4'-disubstituted 2,2' bipyridyl ligands (Rbpy, where R = NH2, tBu, OCH3, H, CF3, CN, NO2) to investigate CO's liberation ability to identify and study such molecules. The calculated absorbance of designed complexes (1-14) shows visible/near-IR region (350-850 nm). The HOMO-LUMO energy gap of 7 (ΔE=2.40 eV) complex and for complex 14 (ΔE=2.28 eV) which is lesser in all complexes but the MLCT percentage is greater in Mn tricarbonyl complexes in comparison to Re tricarbonyl complexes. The calculated results of the FMO approach revealed that complex 7 and 14 have the lowest energy gap which is also in good agreement with DOSs and TDM results. The theoretically calculated results revealed that the both Mn and Re tricarbonyl complexes have a tendency for labialization of CO, but Mn tricarbonyl complexes are more prone to CO release because they have higher MLCT percentage. METHODS In this research work, we have performed density functional theory (DFT) calculations to explore the physical properties of compounds such as bipyridine-related [Mn(CO)3] and [Re(CO)3] and we have compared the physical properties of both manganese and rhenium tricarbonyl complexes in the light of carbon monoxide releasing tendency. DFT-based calculations were performed by using B3LYP/LANL2DZ basis set followed by acetonitrile solvent using the conductor-like polarizable continuum model (CPCM) for different calculations. Various geometrical calculations were performed using the Gaussian16 suite of programs and the output results obtained from Gaussian16 were visualized using GaussView 5.0.16. The same level of theory was used for various calculations, including frontier molecular orbital (FMO) analysis, metal to ligand charge transfer (MLCT), density of state (DOS) calculations, and transition density of matrix (TDM) calculations. For specific calculations, GaussSum 2.2 software package was used to calculate the density of states, and the Multiwfn 3.8 program was used to analyze the transition density matrix, which is presented using heat maps for both electrons and holes.
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Affiliation(s)
- Ritu Seth
- Department of Chemistry, Prof. Rajendra Singh (Rajju Bhaiya) Institute of Physical Sciences for Study and Research, V. B. S. Purvanchal University Jaunpur, UP, Jaunpur, 222003, India
| | - Ajeet Singh
- Department of Chemistry, Prof. Rajendra Singh (Rajju Bhaiya) Institute of Physical Sciences for Study and Research, V. B. S. Purvanchal University Jaunpur, UP, Jaunpur, 222003, India.
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6
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Bera K, Mukherjee A. Chemoselective α-Alkylation of Nitriles with Primary Alcohols by Manganese(I)-Catalysis. Chem Asian J 2023:e202300157. [PMID: 37156742 DOI: 10.1002/asia.202300157] [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: 02/22/2023] [Revised: 04/12/2023] [Indexed: 05/10/2023]
Abstract
A sustainable and easy-to-use protocol for the alkylation of aryl nitriles with the earth-abundant manganese(I) catalyst is presented. The alkylation reaction employs readily available nitriles and naturally abundant alcohols as the coupling partners. The reaction proceeds chemoselectively and encompasses a broad substrate scope with good to excellent yields. The catalytic reaction yields selectively α-branched nitriles and water as the sole byproduct. Experimental studies were executed to understand the mechanism of the catalytic reaction.
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Affiliation(s)
- Krishanu Bera
- Department of Chemistry, Indian Institute of Technology Bhilai, GEC Campus, Sejbahar, Raipur, 492015, Chhattisgarh, India
| | - Arup Mukherjee
- Department of Chemistry, Indian Institute of Technology Bhilai, GEC Campus, Sejbahar, Raipur, 492015, Chhattisgarh, India
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7
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Thomas JM, Kuduvalli SS, T.S A, Sivasankar C. Investigation of the CO releasing ability of azachalcone bound Mn(I) tricarbonyl complexes and their anti‐proliferative properties. Appl Organomet Chem 2022. [DOI: 10.1002/aoc.6896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jisha Mary Thomas
- Catalysis and Energy Laboratory, Department of Chemistry Pondicherry University (A Central University) Puducherry INDIA
| | - Shreyas S. Kuduvalli
- Mahatma Gandhi Medical Advanced Research Institute, Sri Balaji Vidyapeeth (Deemed to‐be) University Puducherry India
| | - Anitha T.S
- Mahatma Gandhi Medical Advanced Research Institute, Sri Balaji Vidyapeeth (Deemed to‐be) University Puducherry India
| | - Chinnappan Sivasankar
- Catalysis and Energy Laboratory, Department of Chemistry Pondicherry University (A Central University) Puducherry INDIA
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8
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Scherpf T, Carr CR, Donnelly LJ, Dubrawski ZS, Gelfand BS, Piers WE. A Mesoionic Carbene-Pyridine Bidentate Ligand That Improves Stability in Electrocatalytic CO 2 Reduction by a Molecular Manganese Catalyst. Inorg Chem 2022; 61:13644-13656. [PMID: 35981323 DOI: 10.1021/acs.inorgchem.2c02689] [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
Tricarbonyl Group 7 complexes have a longstanding history as efficacious CO2 electroreduction catalysts. Typically, these complexes feature an auxiliary 2,2'-bipyridine ligand that assists in redox steps by delocalizing the electron density into the ligand orbitals. While this feature lends to an accessible redox potential for CO2 electroreduction, it also presents challenges for electrocatalysis with Mn because the electron density is removed from metal-ligand bonding orbitals. The results presented here thus introduce a mesoionic carbene (MIC) as a potent ligand platform to promote Mn-based electrocatalysis. The strong σ donation of the N,C-bidentate MIC is shown to help centralize the electron density on the Mn center while also maintaining relevant redox potentials for CO2 electroreduction. Mechanistic investigation supports catalytic turnover at two operative potentials separated by 400 mV. In the low operating potential regime at -1.54 V, Mn(0) species catalyze CO2 to CO and CO32-, which has a maximum rate of 7 ± 5 s-1 and is stable for up to 30.7 h. At higher operating potential at -1.94 V, "Mn(-1)" catalyzes CO2 to CO and H2O with faster turnovers of 200 ± 100 s-1, with the trade-off being less stability at 6.7 h. The relative stabilities of Mn complexes bearing MIC and 4,4'-di-tert-butyl-2,2'-bipyridine were compared by evaluation under the same electrolysis conditions and therefore elucidated that the MIC promotes longevity for CO evolution throughout a 5 h period.
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Affiliation(s)
- Thorsten Scherpf
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Cody R Carr
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Laurie J Donnelly
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Zachary S Dubrawski
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Benjamin S Gelfand
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Warren E Piers
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
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9
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Ossinger S, Prescimone A, Häussinger D, Wenger OS. Manganese(I) Complex with Monodentate Arylisocyanide Ligands Shows Photodissociation Instead of Luminescence. Inorg Chem 2022; 61:10533-10547. [PMID: 35768069 PMCID: PMC9377510 DOI: 10.1021/acs.inorgchem.2c01438] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Recently reported
manganese(I) complexes with chelating arylisocyanide
ligands exhibit luminescent metal-to-ligand charge-transfer (MLCT)
excited states, similar to ruthenium(II) polypyridine complexes with
the same d6 valence electron configuration used for many
different applications in photophysics and photochemistry. However,
chelating arylisocyanide ligands require substantial synthetic effort,
and therefore it seemed attractive to explore the possibility of using
more readily accessible monodentate arylisocyanides instead. Here,
we synthesized the new Mn(I) complex [Mn(CNdippPhOMe2)6]PF6 with the known ligand CNdippPhOMe2 = 4-(3,5-dimethoxyphenyl)-2,6-diisopropylphenylisocyanide. This
complex was investigated by NMR spectroscopy, single-crystal structure
analysis, high-resolution electrospray ionization mass spectrometry
(HR-ESI-MS) measurements, IR spectroscopy supported by density functional
theory (DFT) calculations, cyclic voltammetry, and time-resolved as
well as steady-state UV–vis absorption spectroscopy. The key
finding is that the new Mn(I) complex is nonluminescent and instead
undergoes arylisocyanide ligand loss during continuous visible laser
irradiation into ligand-centered and charge-transfer absorption bands,
presumably owed to the population of dissociative d–d excited
states. Thus, it seems that chelating bi- or tridentate binding motifs
are essential for obtaining emissive MLCT excited states in manganese(I)
arylisocyanides. Our work contributes to understanding the basic properties
of photoactive first-row transition metal complexes and could help
advance the search for alternatives to precious metal-based luminophores,
photocatalysts, and sensors. We
report the synthesis, characterization, and X-ray crystal
structure of an octahedral manganese(I) complex with six monodentate
arylisocyanide ligands that undergoes photoinduced ligand loss.
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Affiliation(s)
- Sascha Ossinger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Daniel Häussinger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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10
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Sinha N, Pfund B, Wegeberg C, Prescimone A, Wenger OS. Cobalt(III) Carbene Complex with an Electronic Excited-State Structure Similar to Cyclometalated Iridium(III) Compounds. J Am Chem Soc 2022; 144:9859-9873. [PMID: 35623627 PMCID: PMC9490849 DOI: 10.1021/jacs.2c02592] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Many organometallic
iridium(III) complexes have photoactive excited
states with mixed metal-to-ligand and intraligand charge transfer
(MLCT/ILCT) character, which form the basis for numerous applications
in photophysics and photochemistry. Cobalt(III) complexes with analogous
MLCT excited-state properties seem to be unknown yet, despite the
fact that iridium(III) and cobalt(III) can adopt identical low-spin
d6 valence electron configurations due to their close chemical
relationship. Using a rigid tridentate chelate ligand (LCNC), in which a central amido π-donor is flanked by two σ-donating
N-heterocyclic carbene subunits, we obtained a robust homoleptic complex
[Co(LCNC)2](PF6), featuring a photoactive
excited state with substantial MLCT character. Compared to the vast
majority of isoelectronic iron(II) complexes, the MLCT state of [Co(LCNC)2](PF6) is long-lived because it
does not deactivate as efficiently into lower-lying metal-centered
excited states; furthermore, it engages directly in photoinduced electron
transfer reactions. The comparison with [Fe(LCNC)2](PF6), as well as structural, electrochemical, and UV–vis
transient absorption studies, provides insight into new ligand design
principles for first-row transition-metal complexes with photophysical
and photochemical properties reminiscent of those known from the platinum
group metals.
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Affiliation(s)
- Narayan Sinha
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Björn Pfund
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Christina Wegeberg
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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11
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Abstract
In this Frontier article, recently discovered chromium(0) and manganese(i) complexes emitting from metal-to-ligand charge transfer (MLCT) excited states are highlighted. Chelating isocyanide ligands give access to this new class of 3d6 emitters with MLCT lifetimes in (or close to) the nanosecond regime in solution at room temperature. Although the so far achievable luminescence quantum yields in these open-shell complexes are yet comparatively low, the photophysical properties of the new chromium(0) and manganese(i) isocyanides are reminiscent of those of well-known ruthenium(ii) polypyridines. Our findings provide insight into how undesired nonradiative MLCT deactivation in 3d6 complexes can be counteracted, and they seem therefore relevant for the further development of new luminescent first-row transition metal complexes based on iron(ii) and cobalt(iii) in addition to chromium(0) and manganese(i). In this Frontier article, recently discovered chromium(0) and manganese(i) complexes emitting from metal-to-ligand charge transfer (MLCT) excited states are highlighted.![]()
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Affiliation(s)
- Christina Wegeberg
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland.
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland.
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12
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Wegeberg C, Wenger OS. Luminescent First-Row Transition Metal Complexes. JACS AU 2021; 1:1860-1876. [PMID: 34841405 PMCID: PMC8611671 DOI: 10.1021/jacsau.1c00353] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Indexed: 05/25/2023]
Abstract
Precious and rare elements have traditionally dominated inorganic photophysics and photochemistry, but now we are witnessing a paradigm shift toward cheaper and more abundant metals. Even though emissive complexes based on selected first-row transition metals have long been known, recent conceptual breakthroughs revealed that a much broader range of elements in different oxidation states are useable for this purpose. Coordination compounds of V, Cr, Mn, Fe, Co, Ni, and Cu now show electronically excited states with unexpected reactivity and photoluminescence behavior. Aside from providing a compact survey of the recent conceptual key advances in this dynamic field, our Perspective identifies the main design strategies that enabled the discovery of fundamentally new types of 3d-metal-based luminophores and photosensitizers operating in solution at room temperature.
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13
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Longetti L, Barillot TR, Puppin M, Ojeda J, Poletto L, van Mourik F, Arrell CA, Chergui M. Ultrafast photoelectron spectroscopy of photoexcited aqueous ferrioxalate. Phys Chem Chem Phys 2021; 23:25308-25316. [PMID: 34747432 DOI: 10.1039/d1cp02872c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photochemistry of metal-organic compounds in solution is determined by both intra- and inter-molecular relaxation processes after photoexcitation. Understanding its prime mechanisms is crucial to optimise the reactive paths and control their outcome. Here we investigate the photoinduced dynamics of aqueous ferrioxalate ([FeIII(C2O4)3]3-) upon 263 nm excitation using ultrafast liquid phase photoelectron spectroscopy (PES). The initial step is found to be a ligand-to-metal electron transfer, occuring on a time scale faster than our time resolution (≲30 fs). Furthermore, we observe that about 25% of the initially formed ferrous species population are lost in ∼2 ps. Cast in the contest of previous ultrafast infrared and X-ray spectroscopic studies, we suggest that upon prompt photoreduction of the metal centre, the excited molecules dissociate in <140 fs into the pair of CO2 and [(CO2)FeII(C2O4)2]3- fragments, with unity quantum yield. About 25% of these pairs geminately recombine in ∼2 ps, due to interaction with the solvent molecules, reforming the ground state of the parent ferric molecule.
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Affiliation(s)
- L Longetti
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - T R Barillot
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - M Puppin
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - J Ojeda
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - L Poletto
- National Research Council of Italy - Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, 35131 Padova, Italy
| | - F van Mourik
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - C A Arrell
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - M Chergui
- Laboratory of Ultrafast Spectroscopy and the Lausanne Centre for Ultrafast Science, ISIC, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
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14
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Ohyama R, Mishima M, Inagaki A. Syntheses and structure of dinuclear metal complexes containing naphthyl-Ir bichromophore. Dalton Trans 2021; 50:12716-12722. [PMID: 34545880 DOI: 10.1039/d1dt01853a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of novel metal complexes were synthesized containing an Ir-cyclometalated bichromophore as a visible-light sensitizer. A new bichromophoric unit containing a naphthyl substituent and methyl substituents on the 2-phenylpyridine chelating ligand was synthesized and characterized for the first time. According to the increased crystallinity of the bichromophoric unit, novel Ir-M metal complexes (M = Pd, Mn, and Ir) were synthesized and fully characterized. The novel Ir-Pd complex maintained photocatalytic activity toward styrenes under visible-light irradiation, and polymerization with p-chlorostyrene, copolymerization with styrene and p-chlorostyrene furnished corresponding polymers.
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Affiliation(s)
- Ryo Ohyama
- Department of Chemistry, Tokyo Metropolitan University, 1-1, Minami-Osawa, Hachioji, 192-0397 Tokyo, Japan.
| | - Masaki Mishima
- Department of Molecular Biophysics, Tokyo University of Pharmacy and Life Sciences, School of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Akiko Inagaki
- Department of Chemistry, Tokyo Metropolitan University, 1-1, Minami-Osawa, Hachioji, 192-0397 Tokyo, Japan.
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15
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Marchi RC, Aguiar I, Camilo MR, Braga AH, Do Nascimento ESP, Santana VT, Nascimento OR, Carlos RM. Photochemical Properties of a Mononuclear Mn(I) Triscarbonyl Complex in Water: An Insight into Different Oxidation States. ChemistrySelect 2021. [DOI: 10.1002/slct.202102283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Rafael C. Marchi
- Chemistry Department Universidade Federal de São Carlos - UFSCar. Rod. Washington Luis São Carlos SP 13565-905 Brazil
| | - Inara Aguiar
- Chemistry Department Universidade Federal de São Carlos - UFSCar. Rod. Washington Luis São Carlos SP 13565-905 Brazil
| | - Mariana R. Camilo
- Chemistry Department Universidade Federal de São Carlos - UFSCar. Rod. Washington Luis São Carlos SP 13565-905 Brazil
| | - Adriano H. Braga
- Chemical Engineering Department Universidade Federal de São Carlos - UFSCar. Rod. Washington Luis São Carlos SP 13565-905 Brazil
| | - Eduardo S. P. Do Nascimento
- Chemistry Department Universidade Federal de São Carlos - UFSCar. Rod. Washington Luis São Carlos SP 13565-905 Brazil
| | - Vinicius T. Santana
- Physics Institute Universidade de São Paulo-EECC Av. Trabalhador São Carlense São Carlos-SP 13560-970 Brazil
| | - Otaciro R. Nascimento
- Physics Institute Universidade de São Paulo-EECC Av. Trabalhador São Carlense São Carlos-SP 13560-970 Brazil
| | - Rose M. Carlos
- Chemistry Department Universidade Federal de São Carlos - UFSCar. Rod. Washington Luis São Carlos SP 13565-905 Brazil
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16
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Mishra I, Priyatharsini M, Sathiyendiran M. Synthesis and characterization of binuclear manganese carbonyl complex of 1,4-bis(2-(2′-hydroxyphenyl)benzimidazol-1-yl)benzene and dimethylaminopyridine. J Organomet Chem 2021. [DOI: 10.1016/j.jorganchem.2021.121934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Herr P, Kerzig C, Larsen CB, Häussinger D, Wenger OS. Manganese(I) complexes with metal-to-ligand charge transfer luminescence and photoreactivity. Nat Chem 2021; 13:956-962. [PMID: 34341527 DOI: 10.1038/s41557-021-00744-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 06/04/2021] [Indexed: 11/09/2022]
Abstract
Precious metal complexes with the d6 valence electron configuration often exhibit luminescent metal-to-ligand charge transfer (MLCT) excited states, which form the basis for many applications in lighting, sensing, solar cells and synthetic photochemistry. Iron(II) has received much attention as a possible Earth-abundant alternative, but to date no iron(II) complex has been reported to show MLCT emission upon continuous-wave excitation. Manganese(I) has the same electron configuration as that of iron(II), but until now has typically been overlooked in the search for cheap MLCT luminophores. Here we report that isocyanide chelate ligands give access to air-stable manganese(I) complexes that exhibit MLCT luminescence in solution at room temperature. These compounds were successfully used as photosensitizers for energy- and electron-transfer reactions and were shown to promote the photoisomerization of trans-stilbene. The observable electron transfer photoreactivity occurred from the emissive MLCT state, whereas the triplet energy transfer photoreactivity originated from a ligand-centred 3π-π* state.
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Affiliation(s)
- Patrick Herr
- Department of Chemistry, University of Basel, Basel, Switzerland
| | - Christoph Kerzig
- Department of Chemistry, University of Basel, Basel, Switzerland
| | | | | | - Oliver S Wenger
- Department of Chemistry, University of Basel, Basel, Switzerland.
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18
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Fumanal M, Daniel C, Gindensperger E. Excited-state dynamics of [Mn(im)(CO) 3(phen)] +: PhotoCORM, catalyst, luminescent probe? J Chem Phys 2021; 154:154102. [PMID: 33887929 DOI: 10.1063/5.0044108] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mn(I) α-diimine carbonyl complexes have shown promise in the development of luminescent CO release materials (photoCORMs) for diagnostic and medical applications due to their ability to balance the energy of the low-lying metal-to-ligand charge transfer (MLCT) and metal-centered (MC) states. In this work, the excited state dynamics of [Mn(im)(CO)3(phen)]+ (im = imidazole; phen = 1,10-phenanthroline) is investigated by means of wavepacket propagation on the potential energy surfaces associated with the 11 low-lying Sn singlet excited states within a vibronic coupling model in a (quasi)-diabatic representation including 16 nuclear degrees of freedom. The results show that the early time photophysics (<400 fs) is controlled by the interaction between two MC dissociative states, namely, S5 and S11, with the lowest S1-S3 MLCT bound states. In particular, the presence of S1/S5 and S2/S11 crossings within the diabatic picture along the Mn-COaxial dissociative coordinate (qMn-COaxial) favors a two-stepwise population of the dissociative states, at about 60-70 fs (S11) and 160-180 fs (S5), which reaches about 10% within 200 fs. The one-dimensional reduced densities associated with the dissociative states along qMn-COaxial as a function of time clearly point to concurrent primary processes, namely, CO release vs entrapping into the S1 and S2 potential wells of the lowest luminescent MLCT states within 400 fs, characteristics of luminescent photoCORM.
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Affiliation(s)
- Maria Fumanal
- Laboratoire de Chimie Quantique, Institut de Chimie Strasbourg, UMR-7177 CNRS/Université de Strasbourg, 1 Rue Blaise Pascal BP 296/R8, F-67008 Strasbourg, France
| | - Chantal Daniel
- Laboratoire de Chimie Quantique, Institut de Chimie Strasbourg, UMR-7177 CNRS/Université de Strasbourg, 1 Rue Blaise Pascal BP 296/R8, F-67008 Strasbourg, France
| | - Etienne Gindensperger
- Laboratoire de Chimie Quantique, Institut de Chimie Strasbourg, UMR-7177 CNRS/Université de Strasbourg, 1 Rue Blaise Pascal BP 296/R8, F-67008 Strasbourg, France
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19
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Henke WC, Kerr TA, Sheridan TR, Henling LM, Takase MK, Day VW, Gray HB, Blakemore JD. Synthesis, structural studies, and redox chemistry of bimetallic [Mn(CO) 3] and [Re(CO) 3] complexes. Dalton Trans 2021; 50:2746-2756. [PMID: 33459317 PMCID: PMC7983307 DOI: 10.1039/d0dt03666h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Manganese ([Mn(CO)3]) and rhenium tricarbonyl ([Re(CO)3]) complexes represent a workhorse family of compounds with applications in a variety of fields. Here, the coordination, structural, and electrochemical properties of a family of mono- and bimetallic [Mn(CO)3] and [Re(CO)3] complexes are explored. In particular, a novel heterobimetallic complex featuring both [Mn(CO)3] and [Re(CO)3] units supported by 2,2'-bipyrimidine (bpm) has been synthesized, structurally characterized, and compared to the analogous monomeric and homobimetallic complexes. To enable a comprehensive structural analysis for the series of complexes, we have carried out new single crystal X-ray diffraction studies of seven compounds: Re(CO)3Cl(bpm), anti-[{Re(CO3)Cl}2(bpm)], Mn(CO)3Br(bpz) (bpz = 2,2'-bipyrazine), Mn(CO)3Br(bpm), syn- and anti-[{Mn(CO3)Br}2(bpm)], and syn-[Mn(CO3)Br(bpm)Re(CO)3Br]. Electrochemical studies reveal that the bimetallic complexes are reduced at much more positive potentials (ΔE≥ 380 mV) compared to their monometallic analogues. This redox behavior is consistent with introduction of the second tricarbonyl unit which inductively withdraws electron density from the bridging, redox-active bpm ligand, resulting in more positive reduction potentials. [Re(CO3)Cl]2(bpm) was reduced with cobaltocene; the electron paramagnetic resonance spectrum of the product exhibits an isotropic signal (near g = 2) characteristic of a ligand-centered bpm radical. Our findings highlight the facile synthesis as well as the structural characteristics and unique electrochemical behavior of this family of complexes.
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Affiliation(s)
- Wade C Henke
- Department of Chemistry, University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, USA.
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20
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Weinstain R, Slanina T, Kand D, Klán P. Visible-to-NIR-Light Activated Release: From Small Molecules to Nanomaterials. Chem Rev 2020; 120:13135-13272. [PMID: 33125209 PMCID: PMC7833475 DOI: 10.1021/acs.chemrev.0c00663] [Citation(s) in RCA: 261] [Impact Index Per Article: 65.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Indexed: 02/08/2023]
Abstract
Photoactivatable (alternatively, photoremovable, photoreleasable, or photocleavable) protecting groups (PPGs), also known as caged or photocaged compounds, are used to enable non-invasive spatiotemporal photochemical control over the release of species of interest. Recent years have seen the development of PPGs activatable by biologically and chemically benign visible and near-infrared (NIR) light. These long-wavelength-absorbing moieties expand the applicability of this powerful method and its accessibility to non-specialist users. This review comprehensively covers organic and transition metal-containing photoactivatable compounds (complexes) that absorb in the visible- and NIR-range to release various leaving groups and gasotransmitters (carbon monoxide, nitric oxide, and hydrogen sulfide). The text also covers visible- and NIR-light-induced photosensitized release using molecular sensitizers, quantum dots, and upconversion and second-harmonic nanoparticles, as well as release via photodynamic (photooxygenation by singlet oxygen) and photothermal effects. Release from photoactivatable polymers, micelles, vesicles, and photoswitches, along with the related emerging field of photopharmacology, is discussed at the end of the review.
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Affiliation(s)
- Roy Weinstain
- School
of Plant Sciences and Food Security, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Tomáš Slanina
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 166 10 Prague, Czech Republic
| | - Dnyaneshwar Kand
- School
of Plant Sciences and Food Security, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Petr Klán
- Department
of Chemistry and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
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21
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Kanno T, Takase T, Oyama D. Effects of Chemically-Modified Polypyridyl Ligands on the Structural and Redox Properties of Tricarbonylmanganese(I) Complexes. Molecules 2020; 25:molecules25245921. [PMID: 33327547 PMCID: PMC7765023 DOI: 10.3390/molecules25245921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/11/2020] [Accepted: 12/11/2020] [Indexed: 11/16/2022] Open
Abstract
Carbonyl complexes with manganese(I) as the central metal are very attractive catalysts. The introduction of redox-active ligands, such as quinones and methyl viologen analogs into these catalysts, would be expected to lead to superior catalyst performances, since they can function as excellent electron carriers. In this study, we synthesized four tricarbonylmanganese(I) complexes containing typical bidentate polypyridyl ligands, including 1,10-phenanthroline (phen) and 2,2′-bipyridine (bpy) frameworks bound to redox-active ortho-quinone/catechol or methyl viologen-like units. The molecular structures of the resulting complexes were determined by X-ray crystallography to clarify their steric features. As expected from the infrared (IR) data, three CO ligands for each complex were coordinated in the facial configuration around the central manganese(I) atom. Additionally, the structural parameters were found to differ significantly between the quinone/catechol units. Electrochemical analysis revealed some differences between them and their reference complexes, namely [MnBr(CO)3(phen)] and [MnBr(CO)3(bpy)]. Notably, interconversions induced by two-electron/two-proton transfers between the quinone and catechol units were observed in the phenanthroline-based complexes. This work indicated that the structural and redox properties in tricarbonylmanganese(I) complexes were significantly affected by chemically modified polypyridyl ligands. A better understanding of structures and redox behaviors of the present compounds would facilitate the design of new manganese complexes with enhanced properties.
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Affiliation(s)
- Takatoshi Kanno
- Graduate School of Science and Engineering, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan;
| | - Tsugiko Takase
- Department of Natural Sciences and Informatics, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan;
| | - Dai Oyama
- Department of Natural Sciences and Informatics, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan;
- Correspondence: ; Tel.: +81-24-548-8199
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22
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Kanno T, Takase T, Oyama D. Synthesis and crystal structures of manganese(I) carbonyl complexes bearing ester-substituted α-di-imine ligands. Acta Crystallogr E Crystallogr Commun 2020; 76:1433-1436. [PMID: 32939295 PMCID: PMC7472766 DOI: 10.1107/s2056989020010750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 08/04/2020] [Indexed: 11/18/2022]
Abstract
The crystal structures of two manganese(I) complexes with ester-substituted bi-pyridine or bi-quinoline supporting ligands are reported, namely, fac-bromido-tricarbon-yl(diethyl 2,2'-bi-pyridine-4,4'-di-carboxyl-ate-κ2 N,N')mangan-ese(I), [MnBr(C16H16N2O4)(CO)3], I, and fac-bromido-tricarbon-yl(diethyl 2,2'-bi-quinoline-4,4'-di-carboxyl-ate-κ2 N,N')manganese(I), [MnBr(C24H20N2O4)(CO)3], II. In both complexes, the manganese(I) atom adopts a distorted octa-hedral coordination sphere defined by three carbonyl C atoms, a Br- anion and two N atoms from the chelating α-di-imine ligand. Both complexes show fac configurations of the carbonyl ligands. In I, the complex mol-ecules are linked by C-H⋯Br hydrogen bonds and aromatic π-π contacts. In II, intra-molecular C-H⋯O hydrogen bonds are present as well as inter-molecular C-H⋯O and C-H⋯Br hydrogen bonds and π-π inter-actions.
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Affiliation(s)
- Takatoshi Kanno
- Graduate School of Science and Engineering, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan
| | - Tsugiko Takase
- Department of Natural Sciences and Informatics, Fukushima University, 1, Kanayagawa, Fukushima 960-1296, Japan
| | - Dai Oyama
- Department of Natural Sciences and Informatics, Fukushima University, 1, Kanayagawa, Fukushima 960-1296, Japan
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23
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Khaled RM, Friedrich A, Ragheb MA, Abdel-Ghani NT, Mansour AM. Cytotoxicity of photoactivatable bromo tricarbonyl manganese(i) compounds against human liver carcinoma cells. Dalton Trans 2020; 49:9294-9305. [PMID: 32578643 DOI: 10.1039/d0dt01539c] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Two series of photoinduced tricarbonyl manganese(i) compounds were prepared from the reaction of [MnBr(CO)3(2-C(H)[double bond, length as m-dash]O)] (2-C(H)[double bond, length as m-dash]O: quinoline-2-carboxaldehyde and pyridine-2-carboxaldehyde) and para-substituted aniline derivatives (X = OH, OCH3, Cl and NO2). Different electron-donating and electron-withdrawing substituents were introduced in the para-position of the phenyl ring to investigate their influence on the stability of the compounds in the dark and the photophysical properties upon illumination at 525 nm. When kept in the dark, the aerated solutions of the complexes in dimethyl sulfoxide (DMSO) and CH2Cl2 were stable. In the solution, the complexes bearing electron-withdrawing substituents, exchange their bromo ligands with DMSO solvent molecules, as evidenced from infrared and UV/Vis studies as well as time-dependent density functional theory (TDDFT) calculations. The complexes were assessed for their cytotoxicity, both in the dark and upon exposure to a 525 nm LED, against the human hepatocarcinoma cell line (HepG2). A marked reduction in the viability of HepG2 cells treated with the complex functionalized with quinoline and methoxy substituent was observed after illumination in a dose-dependent manner, with an IC50 value of 7.1 μM, making it the most phototoxic compound in our study.
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Affiliation(s)
- Rabaa M Khaled
- Department of Chemistry, Faculty of Science, Cairo University, Gamma Street, Giza, Cairo 12613, Egypt.
| | - Alexandra Friedrich
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Mohamed A Ragheb
- Department of Chemistry, Faculty of Science, Cairo University, Gamma Street, Giza, Cairo 12613, Egypt.
| | - Nour T Abdel-Ghani
- Department of Chemistry, Faculty of Science, Cairo University, Gamma Street, Giza, Cairo 12613, Egypt.
| | - Ahmed M Mansour
- Department of Chemistry, Faculty of Science, Cairo University, Gamma Street, Giza, Cairo 12613, Egypt.
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24
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Henke WC, Hopkins JA, Anderson ML, Stiel JP, Day VW, Blakemore JD. 4,5-Diazafluorene and 9,9'-Dimethyl-4,5-Diazafluorene as Ligands Supporting Redox-Active Mn and Ru Complexes. MOLECULES (BASEL, SWITZERLAND) 2020; 25:molecules25143189. [PMID: 32668660 PMCID: PMC7396985 DOI: 10.3390/molecules25143189] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/03/2020] [Accepted: 07/10/2020] [Indexed: 11/16/2022]
Abstract
4,5-diazafluorene (daf) and 9,9’-dimethyl-4,5-diazafluorene (Me2daf) are structurally similar to the important ligand 2,2’-bipyridine (bpy), but significantly less is known about the redox and spectroscopic properties of metal complexes containing Me2daf as a ligand than those containing bpy. New complexes Mn(CO)3Br(daf) (2), Mn(CO)3Br(Me2daf) (3), and [Ru(Me2daf)3](PF6)2 (5) have been prepared and fully characterized to understand the influence of the Me2daf framework on their chemical and electrochemical properties. Structural data for 2, 3, and 5 from single-crystal X-ray diffraction analysis reveal a distinctive widening of the daf and Me2daf chelate angles in comparison to the analogous Mn(CO)3(bpy)Br (1) and [Ru(bpy)3]2+ (4) complexes. Electronic absorption data for these complexes confirm the electronic similarity of daf, Me2daf, and bpy, as spectra are dominated in each case by metal-to-ligand charge transfer bands in the visible region. However, the electrochemical properties of 2, 3, and 5 reveal that the redox-active Me2daf framework in 3 and 5 undergoes reduction at a slightly more negative potential than that of bpy in 1 and 4. Taken together, the results indicate that Me2daf could be useful for preparation of a variety of new redox-active compounds, as it retains the useful redox-active nature of bpy but lacks the acidic, benzylic C–H bonds that can induce secondary reactivity in complexes bearing daf.
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Shipp JD, Carson H, Spall SJP, Parker SC, Chekulaev D, Jones N, Mel'nikov MY, Robertson CC, Meijer AJHM, Weinstein JA. Sterically hindered Re- and Mn-CO 2 reduction catalysts for solar energy conversion. Dalton Trans 2020; 49:4230-4243. [PMID: 32104876 DOI: 10.1039/d0dt00252f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Novel molecular Re and Mn tricarbonyl complexes bearing a bipyridyl ligand functionalised with sterically hindering substituents in the 6,6'-position, [M(HPEAB)(CO)3(X)] (M/X = Re/Cl, Mn/Br; HPEAB = 6,6'-{N-(4-hexylphenyl)-N(ethyl)-amido}-2,2'-bipyridine) have been synthesised, fully characterised including by single crystal X-ray crystallography, and their propensity to act as catalysts for the electrochemical and photochemical reduction of CO2 has been established. Controlled potential electrolysis showed that the catalysts are effective for electrochemical CO2-reduction, yielding CO as the product (in MeCN for the Re-complex, in 95 : 5 (v/v) MeCN : H2O mixture for the Mn-complex). The recyclability of the catalysts was demonstrated through replenishment of CO2 within solution. The novel catalysts had similar reduction potentials to previously reported complexes of similar structure, and results of the foot-of-the-wave analysis showed comparable maximum turnover rates, too. The tentative mechanisms for activation of the pre-catalysts were proposed on the basis of IR-spectroelectrochemical data aided by DFT calculations. It is shown that the typical dimerisation of the Mn-catalyst was prevented by incorporation of sterically hindering groups, whilst the Re-catalyst undergoes the usual mechanism following chloride ion loss. No photochemical CO2 reduction was observed for the rhenium complex in the presence of a sacrificial donor (triethylamine), which was attributed to the short triplet excited state lifetime (3.6 ns), insufficient for diffusion-controlled electron transfer. Importantly, [Mn(HPEAB)(CO)3Br] can act as a CO2 reduction catalyst when photosensitised by a zinc porphyrin under red light irradiation (λ > 600 nm) in MeCN : H2O (95 : 5); there has been only one reported example of photoactivating Mn-catalysts with porphyrins in this manner. Thus, this work demonstrates the wide utility of sterically protected Re- and Mn-diimine carbonyl catalysts, where the rate and yield of CO-production can be adjusted based on the metal centre and catalytic conditions, with the advantage of suppressing unwanted side-reactions through steric protection of the vacant coordination site.
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Affiliation(s)
- James D Shipp
- Department of Chemistry, University of Sheffield, S3 7HF, UK.
| | - Heather Carson
- Department of Chemistry, University of Sheffield, S3 7HF, UK.
| | | | - Simon C Parker
- Department of Chemistry, University of Sheffield, S3 7HF, UK.
| | | | - Natalie Jones
- Department of Chemistry, University of Sheffield, S3 7HF, UK.
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Léval A, Junge H, Beller M. Manganese( i) κ 2- NN complex-catalyzed formic acid dehydrogenation. Catal Sci Technol 2020. [DOI: 10.1039/d0cy00769b] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This work updates the first non-phosphine-based Mn complex able to perform the formic acid dehydrogenation (FA DH) in the presence of amines. Significant improvements were achieved regarding TON (>7500), gas evolution (>20 L), and lower CO content.
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