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Ballico M, Alessi D, Aneggi E, Busato M, Zuccaccia D, Allegri L, Damante G, Jandl C, Baratta W. Cyclometalated and NNN Terpyridine Ruthenium Photocatalysts and Their Cytotoxic Activity. Molecules 2024; 29:2146. [PMID: 38731639 PMCID: PMC11085208 DOI: 10.3390/molecules29092146] [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: 03/30/2024] [Revised: 04/16/2024] [Accepted: 04/30/2024] [Indexed: 05/13/2024] Open
Abstract
The cyclometalated terpyridine complexes [Ru(η2-OAc)(NC-tpy)(PP)] (PP = dppb 1, (R,R)-Skewphos 4, (S,S)-Skewphos 5) are easily obtained from the acetate derivatives [Ru(η2-OAc)2(PP)] (PP = dppb, (R,R)-Skewphos 2, (S,S)-Skewphos 3) and tpy in methanol by elimination of AcOH. The precursors 2, 3 are prepared from [Ru(η2-OAc)2(PPh3)2] and Skewphos in cyclohexane. Conversely, the NNN complexes [Ru(η1-OAc)(NNN-tpy)(PP)]OAc (PP = (R,R)-Skewphos 6, (S,S)-Skewphos 7) are synthesized in a one pot reaction from [Ru(η2-OAc)2(PPh3)2], PP and tpy in methanol. The neutral NC-tpy 1, 4, 5 and cationic NNN-tpy 6, 7 complexes catalyze the transfer hydrogenation of acetophenone (S/C = 1000) in 2-propanol with NaOiPr under light irradiation at 30 °C. Formation of (S)-1-phenylethanol has been observed with 4, 6 in a MeOH/iPrOH mixture, whereas the R-enantiomer is obtained with 5, 7 (50-52% ee). The tpy complexes show cytotoxic activity against the anaplastic thyroid cancer 8505C and SW1736 cell lines (ED50 = 0.31-8.53 µM), with the cationic 7 displaying an ED50 of 0.31 µM, four times lower compared to the enantiomer 6.
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Affiliation(s)
- Maurizio Ballico
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Via Cotonificio 108, I-33100 Udine, Italy; (D.A.); (E.A.); (M.B.); (D.Z.)
| | - Dario Alessi
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Via Cotonificio 108, I-33100 Udine, Italy; (D.A.); (E.A.); (M.B.); (D.Z.)
| | - Eleonora Aneggi
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Via Cotonificio 108, I-33100 Udine, Italy; (D.A.); (E.A.); (M.B.); (D.Z.)
| | - Marta Busato
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Via Cotonificio 108, I-33100 Udine, Italy; (D.A.); (E.A.); (M.B.); (D.Z.)
| | - Daniele Zuccaccia
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Via Cotonificio 108, I-33100 Udine, Italy; (D.A.); (E.A.); (M.B.); (D.Z.)
| | - Lorenzo Allegri
- Dipartimento di Medicina, Istituto di Genetica Medica, Università di Udine, Via Chiusaforte, F3, I-33100 Udine, Italy; (L.A.); (G.D.)
| | - Giuseppe Damante
- Dipartimento di Medicina, Istituto di Genetica Medica, Università di Udine, Via Chiusaforte, F3, I-33100 Udine, Italy; (L.A.); (G.D.)
| | - Christian Jandl
- Department of Chemistry & Catalysis Research Center, Technische Universität München, Ernst-Otto-Fischer-Str. 1, 85748 Garching bei München, Germany;
| | - Walter Baratta
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, Università di Udine, Via Cotonificio 108, I-33100 Udine, Italy; (D.A.); (E.A.); (M.B.); (D.Z.)
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2
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Hennessey S, González-Gómez R, McCarthy K, Burke CS, Le Houérou C, Sarangi NK, McArdle P, Keyes TE, Cucinotta F, Farràs P. Enhanced Photostability and Photoactivity of Ruthenium Polypyridyl-Based Photocatalysts by Covalently Anchoring Onto Reduced Graphene Oxide. ACS OMEGA 2024; 9:13872-13882. [PMID: 38559923 PMCID: PMC10976380 DOI: 10.1021/acsomega.3c08800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 01/19/2024] [Accepted: 02/29/2024] [Indexed: 04/04/2024]
Abstract
Recentstudies toward finding more efficient ruthenium metalloligands for photocatalysis applications have shown that the derivatives of the linear [Ru(dqp)2]2+ (dqp: 2,6-di(quinolin-8-yl)-pyridine) complexes hold significant promise due to their extended emission lifetime in the μs time scale while retaining comparable redox potential, extinction coefficients, and absorption profile in the visible region to [Ru(bpy)3]2+ (bpy: 2,2'-bipyridine) and [Ru(tpy)2]2+ (tpy: 2,2':6',2″-terpyridine) complexes. Nevertheless, its photostability in aqueous solution needs to be improved for its widespread use in photocatalysis. Carbon-based supports have arisen as potential solutions for improving photostability and photocatalytic activity, yet their effect greatly depends on the interaction of the metal complex with the support. Herein, we present a strategy for obtaining Ru-polypyridyl complexes covalently linked to aminated reduced graphene oxide (rGO) to generate novel materials with long-term photostability and increased photoactivity. Specifically, the hybrid Ru(dqp)@rGO system has shown excellent photostable behavior during 24 h of continual irradiation, with an enhancement of 10 and 15% of photocatalytic dye degradation in comparison with [Ru(dqp)2]2+ and Ru(tpy)@rGO, respectively, as well as remarkable recyclability. The presented strategy corroborates the potential of [Ru(dqp)2]2+ as an interesting photoactive molecule to produce more advantageous light-active materials by covalent attachment onto carbon-based supports.
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Affiliation(s)
- Seán Hennessey
- School
of Biological and Chemical Sciences, Energy Research Centre, Ryan Institute, University of Galway, H91 CF50 Galway, Ireland
| | - Roberto González-Gómez
- School
of Biological and Chemical Sciences, Energy Research Centre, Ryan Institute, University of Galway, H91 CF50 Galway, Ireland
| | - Kathryn McCarthy
- School
of Biological and Chemical Sciences, Energy Research Centre, Ryan Institute, University of Galway, H91 CF50 Galway, Ireland
| | - Christopher S. Burke
- School
of Chemical Sciences, National Centre for Sensor Research, Dublin City University, Dublin 9, Ireland
- School
of Chemistry and Analytical and Biological Chemistry Research Facility
(ABCRF), University College Cork, T12 K8AF Cork, Ireland
| | - Camille Le Houérou
- School
of Biological and Chemical Sciences, Energy Research Centre, Ryan Institute, University of Galway, H91 CF50 Galway, Ireland
| | - Nirod Kumar Sarangi
- School
of Chemical Sciences, National Centre for Sensor Research, Dublin City University, Dublin 9, Ireland
| | - Patrick McArdle
- School
of Biological and Chemical Sciences, Energy Research Centre, Ryan Institute, University of Galway, H91 CF50 Galway, Ireland
| | - Tia E. Keyes
- School
of Chemical Sciences, National Centre for Sensor Research, Dublin City University, Dublin 9, Ireland
| | - Fabio Cucinotta
- School
of Natural and Environmental Sciences, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K.
| | - Pau Farràs
- School
of Biological and Chemical Sciences, Energy Research Centre, Ryan Institute, University of Galway, H91 CF50 Galway, Ireland
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3
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Kim D, Dang VQ, Teets TS. Improved transition metal photosensitizers to drive advances in photocatalysis. Chem Sci 2023; 15:77-94. [PMID: 38131090 PMCID: PMC10732135 DOI: 10.1039/d3sc04580c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/22/2023] [Indexed: 12/23/2023] Open
Abstract
To function effectively in a photocatalytic application, a photosensitizer's light absorption, excited-state lifetime, and redox potentials, both in the ground state and excited state, are critically important. The absorption profile is particularly relevant to applications involving solar harvesting, whereas the redox potentials and excited-state lifetimes determine the thermodynamics, kinetics, and quantum yields of photoinduced redox processes. This perspective article focuses on synthetic inorganic and organometallic approaches to optimize these three characteristics of transition-metal based photosensitizers. We include our own work in these areas, which has focused extensively on exceptionally strong cyclometalated iridium photoreductants that enable challenging reductive photoredox transformations on organic substrates, and more recent work which has led to improved solar harvesting in charge-transfer copper(i) chromophores, an emerging class of earth-abundant compounds particularly relevant to solar-energy applications. We also extensively highlight many other complementary strategies for optimizing these parameters and highlight representative examples from the recent literature. It remains a significant challenge to simultaneously optimize all three of these parameters at once, since improvements in one often come at the detriment of the others. These inherent trade-offs and approaches to obviate or circumvent them are discussed throughout.
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Affiliation(s)
- Dooyoung Kim
- University of Houston, Department of Chemistry 3585 Cullen Blvd. Room 112 Houston TX 77204-5003 USA
| | - Vinh Q Dang
- University of Houston, Department of Chemistry 3585 Cullen Blvd. Room 112 Houston TX 77204-5003 USA
| | - Thomas S Teets
- University of Houston, Department of Chemistry 3585 Cullen Blvd. Room 112 Houston TX 77204-5003 USA
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4
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Shang Y, Zhang Z, Huang M, Shu N, Luo H, Cao Q, Fan B, Han Y, Fang M, Wu Y, Xu J. Computational study of the photophysical properties and electronic structure of iridium(III) photosensitizer complexes with electron-withdrawing groups. Phys Chem Chem Phys 2023; 25:32666-32674. [PMID: 38010916 DOI: 10.1039/d3cp04900k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
A series of novel [Ir(tpy)(btp)Cl]+ complexes (Ir1-Ir4) have been reported to show excellent performance as photosensitizers. The introduction of electron-withdrawing groups increases visible light absorption and the lifetime of triplet states. To improve the photophysical properties, we theoretically design Ir5-Ir9 with electron-withdrawing groups (Cl, F, COOH, CN and NO2). Surprisingly, our findings indicate that the photosensitizer performance does not strictly increase with the electron-withdrawing ability of the substituents. In this work, the geometric and electronic structures, transition features, and photophysical properties of Ir1-Ir9 are investigated. The natural transition orbital (NTO) analysis indicates that the T1 and T2 states play a role in the photochemical pathways. Ultraviolet-visible (UV-vis) absorption spectra and charge-transfer spectra (CTS) have been investigated to show that the introduction of electron-withdrawing groups not only improves the visible light absorbing ability, but also changes the nature of electron excitation, providing a future molecular design strategy for similar series of photosensitizers. The rates of (reverse) intersystem crossing and the Huang-Rhys factors are evaluated to interpret the experimental results within the framework of Marcus theory. For complexes Ir1-Ir7, the introduction of electron-withdrawing groups leads to a lower efficiency of reverse intersystem crossing and a strong non-radiative process T2 → T1, resulting in a long triplet lifetime and excellent performance as a photosensitizer. Furthermore, some newly designed complexes (Ir7-Ir9) show great potential as thermally activated delayed fluorescence emitters, contrary to our initial expectations.
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Affiliation(s)
- Yunlong Shang
- Laboratory of Molecular Modeling and Design, State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, P. R. China
- School of Chemical Science, University of Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Zhoujie Zhang
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Mengping Huang
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Na Shu
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Hanyu Luo
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Qiyan Cao
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Bingbing Fan
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Yu Han
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Min Fang
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
- State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210023, Jiangsu, P. R. China
| | - Yong Wu
- Jiangsu Key Laboratory for Numerical Simulation of Large-Scale Complex Systems and School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, Jiangsu, P. R. China.
| | - Jiawei Xu
- Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China.
- School of Chemical Science, University of Chinese Academy of Sciences, Beijing 100190, P. R. China
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5
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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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6
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Barker M, Whittemore TJ, London HC, Sledesky JM, Harris EA, Smith Pellizzeri TM, McMillen CD, Wagenknecht PS. Design Strategies for Luminescent Titanocenes: Improving the Photoluminescence and Photostability of Arylethynyltitanocenes. Inorg Chem 2023; 62:17870-17882. [PMID: 37831503 PMCID: PMC10618925 DOI: 10.1021/acs.inorgchem.3c02712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Indexed: 10/14/2023]
Abstract
Complexes that undergo ligand-to-metal charge transfer (LMCT) to d0 metals are of interest as possible photocatalysts. Cp2Ti(C2Ph)2 (where C2Ph = phenylethynyl) was reported to be weakly emissive in room-temperature (RT) fluid solution from its phenylethynyl-to-Ti 3LMCT state but readily photodecomposes. Coordination of CuX between the alkyne ligands to give Cp2Ti(C2Ph)2CuX (X = Cl, Br) has been shown to significantly increase the photostability, but such complexes are not emissive in RT solution. Herein, we investigate whether inhibition of alkyne-Ti-alkyne bond compression might be responsible for the increased photostability of the CuX complexes by investigating the decomposition of a structurally constrained analogue, Cp2Ti(OBET) (OBET = o-bis(ethynyl)tolane). To investigate the mechanism of nonradiative decay from the 3LMCT states in Cp2Ti(C2Ph)2CuX, the photophysical properties were investigated both upon deuteration and upon rigidifying in a poly(methyl methacrylate) film. These investigations suggested that inhibition of structural rearrangement may play a dominant role in increasing emission lifetimes and quantum yields. The bulkier Cp*2Ti(C2Ph)2CuBr was prepared and is emissive at 693 nm in RT THF solution with a photoluminescent quantum yield of 1.3 × 10-3 (τ = 0.18 μs). Time-dependent density functional theory (TDDFT) calculations suggest that emission occurs from a 3LMCT state dominated by Cp*-to-Ti charge transfer.
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Affiliation(s)
- Matilda Barker
- Department
of Chemistry, Furman University, Greenville, South Carolina 29609, United States
| | - Thomas J. Whittemore
- Department
of Chemistry, Furman University, Greenville, South Carolina 29609, United States
| | - Henry C. London
- Department
of Chemistry, Furman University, Greenville, South Carolina 29609, United States
| | - Jack M. Sledesky
- Department
of Chemistry, Furman University, Greenville, South Carolina 29609, United States
| | - Elizabeth A. Harris
- Department
of Chemistry, Furman University, Greenville, South Carolina 29609, United States
| | - Tiffany M. Smith Pellizzeri
- Department
of Chemistry and Biochemistry, Eastern Illinois
University, Charleston, Illinois 61920, United States
| | - Colin D. McMillen
- Department
of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
| | - Paul S. Wagenknecht
- Department
of Chemistry, Furman University, Greenville, South Carolina 29609, United States
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7
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Feng Z, Riemann L, Guo Z, Herrero D, Simon M, Golz C, Mata RA, Alcarazo M. Pentafluorocyclopropanation of (Hetero)arenes Using Sulfonium Salts: Applications in Late-Stage Functionalization. Angew Chem Int Ed Engl 2023; 62:e202306764. [PMID: 37402213 DOI: 10.1002/anie.202306764] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/03/2023] [Accepted: 07/03/2023] [Indexed: 07/06/2023]
Abstract
The evaluation of the pentafluorocyclopropyl group as a chemotype in crop protection and medicinal chemistry has been hampered in the past by the lack of suitable methodologies that enable the practical incorporation of this moiety into advanced synthetic intermediates. Herein, we report the gram-scale synthesis of an unprecedented sulfonium salt, 5-(pentafluorocyclopropyl)dibenzothiophenium triflate, and its use as a versatile reagent for the photoinduced C-H pentafluorocyclopropylation of a broad series of non-previously functionalized (hetero)arenes through a radical mediated mechanism. The scope and potential benefits of the protocol developed are further demonstrated by the late-stage introduction of the pentafluorocyclopropyl unit into biologically relevant molecules and widely used pharmaceuticals.
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Affiliation(s)
- Zeyu Feng
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Lucas Riemann
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Zichen Guo
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - David Herrero
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Martin Simon
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Christopher Golz
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Ricardo A Mata
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstr 6, 37077, Göttingen, Germany
| | - Manuel Alcarazo
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
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8
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Liu J, Perez OM, Lavergne D, Rasu L, Murphy E, Galvez-Rodriguez A, Bergens SH. One-Step Electropolymerization of a Dicyanobenzene-Carbazole-Imidazole Dye to Prepare Photoactive Redox Polymer Films. Polymers (Basel) 2023; 15:3340. [PMID: 37631397 PMCID: PMC10457835 DOI: 10.3390/polym15163340] [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: 07/07/2023] [Revised: 07/25/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
To the best of our knowledge, this study reports the first direct electropolymerization of a dicyanobenzene-carbazole dye functionalized with an imidazole group to prepare redox- and photoactive porous organic polymer (POP) films in controlled amounts. The POP films were grown on indium-doped tin oxide (ITO) and carbon surfaces using a new monomer, 1-imidazole-2,4,6-tri(carbazol-9-yl)-3,5-dicyanobenzene (1, 3CzImIPN), through a simple one-step process. The structure and activities of the POP films were investigated as photoelectrodes for electrooxidations, as heterogeneous photocatalysts for photosynthetic olefin isomerizations, and for solid-state photoluminescence behavior tunable by lithium-ion concentrations in solution. The results demonstrate that the photoredox-POPs can be used as efficient photocatalysts, and they have potential applications in sensing.
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Affiliation(s)
| | | | | | | | | | | | - Steven H. Bergens
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
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9
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Barth AT, Fajardo J, Sattler W, Winkler JR, Gray HB. Electronic Structures and Photoredox Chemistry of Tungsten(0) Arylisocyanides. Acc Chem Res 2023. [PMID: 37384787 DOI: 10.1021/acs.accounts.3c00184] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
ConspectusThe high energy barriers associated with the reaction chemistry of inert substrates can be overcome by employing redox-active photocatalysts. Research in this area has grown exponentially over the past decade, as transition metal photosensitizers have been shown to mediate challenging organic transformations. Critical for the advancement of photoredox catalysis is the discovery, development, and study of complexes based on earth-abundant metals that can replace and/or complement established noble-metal-based photosensitizers.Recent work has focused on redox-active complexes of 3d metals, as photosensitizers containing these metals most likely would be scalable. Although low lying spin doublet ("spin flip") excited states of chromium(III) and metal-to-ligand charge transfer (MLCT) excited states of copper(I) have relatively long lifetimes, the electronic excited states of many other 3d metal complexes fall on dissociative potential energy surfaces, owing to the population of highly energetic σ-antibonding orbitals. Indeed, we and other investigators have shown that low lying spin singlet and triplet excited states of robust closed-shell metal complexes are too short-lived at room temperature to engage in bimolecular reactions in solutions. In principle, this problem could be overcome by designing and constructing 3d metal complexes containing strong field π-acceptor ligands, where thermally equilibrated MLCT or intraligand charge transfer excited states might fall well below the upper surfaces of dissociative 3d-3d states. Notably, such design elements have been exploited by investigators in very recent work on redox-active iron(II) systems. Another approach, one we have actively pursued, is to design and construct closed-shell complexes of earth-abundant 5d metals containing very strong π-acceptor ligands, where vertical excitation of 5d-5d excited states at the ground state geometry would require energies far above minima in the potential surfaces of MLCT excited states. As this requirement is met by tungsten(0) arylisocyanides, these complexes have been the focus of our work aimed at the development of robust redox-active photosensitizers.In the following Account, we review recent work on homoleptic tungsten(0) arylisocyanides. Originally reported by our group 45 years ago, W(CNAr)6 complexes have exceptionally large one- and two-photon absorption cross-sections. One- or two-photon excitation produces relatively long-lived (hundreds of nanoseconds to microsecond) MLCT excited states in high yields. These MLCT excited states, which are very strong reductants with E°(W+/*W0) = -2.2 to -3.0 V vs Fc[+/0], mediate photocatalysis of organic reactions with both visible and near-infrared (NIR) light. Here, we highlight design principles that led to the development of three generations of W(CNAr)6 photosensitizers; and we discuss likely steps in the mechanism of a prototypal W(CNAr)6-catalyzed base-promoted homolytic aromatic substitution reaction. Among the many potential applications of these very bright luminophores, two-photon imaging and two-photon-initiated polymerization are ones we plan to pursue.
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Affiliation(s)
- Alexandra T Barth
- Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Javier Fajardo
- Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Wesley Sattler
- Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Jay R Winkler
- Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Harry B Gray
- Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
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10
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Leary DC, Zhang Y, Rodriguez JG, Akhmedov NG, Petersen JL, Dolinar BS, Milsmann C. Organometallic Intermediates in the Synthesis of Photoluminescent Zirconium and Hafnium Complexes with Pyridine Dipyrrolide Ligands. Organometallics 2023. [DOI: 10.1021/acs.organomet.3c00058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Affiliation(s)
- Dylan C. Leary
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Yu Zhang
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Jose G. Rodriguez
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Novruz G. Akhmedov
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Jeffrey L. Petersen
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Brian S. Dolinar
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Carsten Milsmann
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
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11
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Feng Z, Marset X, Tostado J, Kircher J, She Z, Golz C, Mata RA, Simon M, Alcarazo M. 5-(Trifluorovinyl)dibenzothiophenium Triflate: Introducing the 1,1,2-Trifluoroethylene Tether in Drug-Like Structures. Chemistry 2022; 29:e202203966. [PMID: 36545870 DOI: 10.1002/chem.202203966] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 12/21/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022]
Abstract
This manuscript reports the synthesis and structure of an unprecedented sulfonium salt, 5-(trifluorovinyl)dibenzothiophenium triflate, and its use as a versatile reagent for the introduction of the bioisosteric 1,1,2-trifluoroethylene linker in drug-like structures. The protocol developed consists of the reaction of this compound with alcohols and phenols to deliver a complete set of 1,2,2-trifluoro-2-(alkoxy-/aryloxy)ethyl sulfonium salts, which have been purified by column chromatography and fully characterized. Subsequent single electron reduction under mild photochemical conditions efficiently affords the corresponding fluoroalkyl radicals that are trapped either intra- or intermolecularly through their reaction with (hetero)arenes. Theoretical calculations are used to evaluate the conformational consequences derived from the presence of the CF2 -CHF tether.
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Affiliation(s)
- Zeyu Feng
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Xavier Marset
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Jaime Tostado
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Johannes Kircher
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstr 6, 37077, Göttingen, Germany
| | - Zhijie She
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Christopher Golz
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Ricardo A Mata
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstr 6, 37077, Göttingen, Germany
| | - Martin Simon
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
| | - Manuel Alcarazo
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077, Göttingen, Germany
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12
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Ballico M, Alessi D, Jandl C, Lovison D, Baratta W. Terpyridine Diphosphine Ruthenium Complexes as Efficient Photocatalysts for the Transfer Hydrogenation of Carbonyl Compounds. Chemistry 2022; 28:e202201722. [PMID: 36001351 PMCID: PMC9828271 DOI: 10.1002/chem.202201722] [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: 06/04/2022] [Indexed: 01/12/2023]
Abstract
The cationic achiral and chiral terpyridine diphosphine ruthenium complexes [RuCl(PP)(tpy)]Cl (PP=dppp (1), (R,R)-Skewphos (2) and (S,S)-Skewphos (3)) are easily obtained in 85-88 % yield through a one-pot synthesis from [RuCl2 (PPh3 )3 ], the diphosphine and 2,2':6',2''-terpyridine (tpy) in 1-butanol. Treatment of 1-3 with NaPF6 in methanol at RT affords quantitatively the corresponding derivatives [RuCl(PP)(tpy)]PF6 (PP=dppp (1 a), (R,R)-Skewphos (2 a) and (S,S)-Skewphos (3 a)). Reaction of [RuCl2 (PPh3 )3 ] with (S,R)-Josiphos or (R)-BINAP in toluene, followed by treatment with tpy in 1-butanol and finally with NaPF6 in MeOH gives [RuCl(PP)(tpy)]PF6 (PP=(S,R)-Josiphos (4 a), (R)-BINAP (5 a)) isolated in 78 % and 86 % yield, respectively. The chiral derivatives have been isolated as single stereoisomers and 3 a, 4 a have been characterized by single crystal X-ray diffraction studies. The tpy complexes with NaOiPr display high photocatalytic activity in the transfer hydrogenation (TH) of carbonyl compounds using 2-propanol as the only hydrogen donor and visible light at 30 °C, at remarkably high S/C (up to 5000) and TOF values up to 264 h-1 . The chiral enantiomers 2, 2 a and 3, 3 a induce the asymmetric photocatalytic TH of acetophenone, affording (S)- and (R)-1-phenylethanol with 51 and 52 % ee, respectively, in a MeOH/2-propanol mixture.
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Affiliation(s)
- Maurizio Ballico
- Dipartimento di Scienze AgroAlimentariAmbientali e Animali (DI4A)Università di UdineVia Cotonificio 10833100UdineItaly
| | - Dario Alessi
- Dipartimento di Scienze AgroAlimentariAmbientali e Animali (DI4A)Università di UdineVia Cotonificio 10833100UdineItaly
| | - Christian Jandl
- Department of Chemistry & Catalysis Research CenterTUMLichtenbergstraße 485747Garching b. MünchenGermany
| | - Denise Lovison
- Dipartimento di Scienze AgroAlimentariAmbientali e Animali (DI4A)Università di UdineVia Cotonificio 10833100UdineItaly
| | - Walter Baratta
- Dipartimento di Scienze AgroAlimentariAmbientali e Animali (DI4A)Università di UdineVia Cotonificio 10833100UdineItaly
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13
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Olumba ME, O’Donnell RM, Rohrabaugh TN, Teets TS. Panchromatic Excited-State Absorption in Bis-Cyclometalated Iridium Isocyanide Complexes. Inorg Chem 2022; 61:19344-19353. [DOI: 10.1021/acs.inorgchem.2c03136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Morris E. Olumba
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas77204-5003, United States
| | - Ryan M. O’Donnell
- U.S. Army Combat Capabilities Development Command, Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland20783, United States
| | - Thomas N. Rohrabaugh
- U.S. Army Combat Capabilities Development Command, Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland20783, United States
| | - Thomas S. Teets
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas77204-5003, United States
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14
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Moore JT, Dorantes MJ, Pengmei Z, Schwartz TM, Schaffner J, Apps SL, Gaggioli CA, Das U, Gagliardi L, Blank DA, Lu CC. Light-Driven Hydrodefluorination of Electron-Rich Aryl Fluorides by an Anionic Rhodium-Gallium Photoredox Catalyst. Angew Chem Int Ed Engl 2022; 61:e202205575. [PMID: 36017770 PMCID: PMC9826370 DOI: 10.1002/anie.202205575] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Indexed: 01/11/2023]
Abstract
An anionic Rh-Ga complex catalyzed the hydrodefluorination of challenging C-F bonds in electron-rich aryl fluorides and trifluoromethylarenes when irradiated with violet light in the presence of H2 , a stoichiometric alkoxide base, and a crown-ether additive. Based on theoretical calculations, the lowest unoccupied molecular orbital (LUMO), which is delocalized across both the Rh and Ga atoms, becomes singly occupied upon excitation, thereby poising the Rh-Ga complex for photoinduced single-electron transfer (SET). Stoichiometric and control reactions support that the C-F activation is mediated by the excited anionic Rh-Ga complex. After SET, the proposed neutral Rh0 intermediate was detected by EPR spectroscopy, which matched the spectrum of an independently synthesized sample. Deuterium-labeling studies corroborate the generation of aryl radicals during catalysis and their subsequent hydrogen-atom abstraction from the THF solvent to generate the hydrodefluorinated arene products. Altogether, the combined experimental and theoretical data support an unconventional bimetallic excitation that achieves the activation of strong C-F bonds and uses H2 and base as the terminal reductant.
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Affiliation(s)
- James T. Moore
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Michael J. Dorantes
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Zihan Pengmei
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Timothy M. Schwartz
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA,Institut für Anorganische ChemieUniversität BonnGerhard-Domagk-Str. 1Bonn53121Deutschland
| | - Jacob Schaffner
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Samantha L. Apps
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Carlo A. Gaggioli
- Department of ChemistryUniversity of Chicago5735 S Ellis Ave.ChicagoIllinois60637USA
| | - Ujjal Das
- Institut für Anorganische ChemieUniversität BonnGerhard-Domagk-Str. 1Bonn53121Deutschland
| | - Laura Gagliardi
- Department of ChemistryUniversity of Chicago5735 S Ellis Ave.ChicagoIllinois60637USA
| | - David A. Blank
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA
| | - Connie C. Lu
- Department of ChemistryUniversity of Minnesota207 Pleasant Street SEMinneapolisMinnesota55455-0431USA,Institut für Anorganische ChemieUniversität BonnGerhard-Domagk-Str. 1Bonn53121Deutschland
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15
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Moore JT, Dorantes MJ, Pengmei Z, Schwartz TM, Schaffner J, Apps SL, Gaggioli CA, Das U, Gagliardi L, Blank DA, Lu CC. Light‐Driven Hydrodefluorination of Electron‐Rich Aryl Fluorides by an Anionic Rhodium‐Gallium Photoredox Catalyst. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- James T. Moore
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Michael J. Dorantes
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Zihan Pengmei
- University of Chicago Department of Chemistry Chemistry UNITED STATES
| | - Timothy M. Schwartz
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Inorganic Chemistry GERMANY
| | - Jacob Schaffner
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Samantha L. Apps
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Carlo A. Gaggioli
- University of Chicago Department of Chemistry Chemistry UNITED STATES
| | - Ujjal Das
- University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn Inorganic Chemistry GERMANY
| | - Laura Gagliardi
- University of Chicago Department of Chemistry Chemistry UNITED STATES
| | - David A. Blank
- University of Minnesota College of Science and Engineering Chemistry UNITED STATES
| | - Connie C. Lu
- University of Minnesota College of Science and Engineering Chemistry Gerhard-Domagk-Straße 1 53121 Bonn GERMANY
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16
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Glaser F, Wenger OS. Red Light-Based Dual Photoredox Strategy Resembling the Z-Scheme of Natural Photosynthesis. JACS AU 2022; 2:1488-1503. [PMID: 35783177 PMCID: PMC9241018 DOI: 10.1021/jacsau.2c00265] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 05/11/2023]
Abstract
Photoredox catalysis typically relies on the use of single chromophores, whereas strategies, in which two different light absorbers are combined, are rare. In photosystems I and II of green plants, the two separate chromophores P680 and P700 both absorb light independently of one another, and then their excitation energy is combined in the so-called Z-scheme, to drive an overall reaction that is thermodynamically very demanding. Here, we adapt this concept to perform photoredox reactions on organic substrates with the combined energy input of two red photons instead of blue or UV light. Specifically, a CuI bis(α-diimine) complex in combination with in situ formed 9,10-dicyanoanthracenyl radical anion in the presence of excess diisopropylethylamine catalyzes ca. 50 dehalogenation and detosylation reactions. This dual photoredox approach seems useful because red light is less damaging and has a greater penetration depth than blue or UV radiation. UV-vis transient absorption spectroscopy reveals that the subtle change in solvent from acetonitrile to acetone induces a changeover in the reaction mechanism, involving either a dominant photoinduced electron transfer or a dominant triplet-triplet energy transfer pathway. Our study illustrates the mechanistic complexity in systems operating under multiphotonic excitation conditions, and it provides insights into how the competition between desirable and unwanted reaction steps can become more controllable.
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17
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Bortolato T, Cuadros S, Simionato G, Dell'Amico L. The advent and development of organophotoredox catalysis. Chem Commun (Camb) 2022; 58:1263-1283. [PMID: 34994368 DOI: 10.1039/d1cc05850a] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In the last decade, photoredox catalysis has unlocked unprecedented reactivities in synthetic organic chemistry. Seminal advancements in the field have involved the use of well-studied metal complexes as photoredox catalysts (PCs). More recently, the synthetic community, looking for more sustainable approaches, has been moving towards the use of purely organic molecules. Organic PCs are generally cheaper and less toxic, while allowing their rational modification to an increased generality. Furthermore, organic PCs have allowed reactivities that are inaccessible by using common metal complexes. Likewise, in synthetic catalysis, the field of photocatalysis is now experiencing a green evolution moving from metal catalysis to organocatalysis. In this feature article, we discuss and critically comment on the scientific reasons for this ongoing evolution in the field of photoredox catalysis, showing how and when organic PCs can efficiently replace their metal counterparts.
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Affiliation(s)
- Tommaso Bortolato
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, Padova, 35131, Italy.
| | - Sara Cuadros
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, Padova, 35131, Italy.
| | - Gianluca Simionato
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, Padova, 35131, Italy.
| | - Luca Dell'Amico
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, Padova, 35131, Italy.
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18
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Olasunkanmi LO, Govender PP. Theoretical probe of absorption and fluorescence emission characteristics of highly luminescent ReL(CO)3X (L = 12H-indazolo[5,6-f][1,10]phenanthroline and X = F, Cl, Br, I): a DFT/TD-DFT study. Mol Phys 2021. [DOI: 10.1080/00268976.2021.2018062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Lukman O. Olasunkanmi
- Department of Chemical Sciences, University of Johannesburg Johannesburg, South Africa
- Department of Chemistry, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Nigeria
| | - Penny P. Govender
- Department of Chemical Sciences, University of Johannesburg Johannesburg, South Africa
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19
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Dandia A, Saini P, Sethi M, Kumar K, Saini S, Meena S, Meena S, Parewa V. Nanocarbons in quantum regime: An emerging sustainable catalytic platform for organic synthesis. CATALYSIS REVIEWS 2021. [DOI: 10.1080/01614940.2021.1985866] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Anshu Dandia
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Pratibha Saini
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Mukul Sethi
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Krishan Kumar
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Surendra Saini
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Savita Meena
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Swati Meena
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
| | - Vijay Parewa
- Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
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20
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López-López JC, Bautista D, González-Herrero P. Luminescent halido(aryl) Pt(IV) complexes obtained via oxidative addition of iodobenzene or diaryliodonium salts to bis-cyclometalated Pt(II) precursors. Dalton Trans 2021; 50:13294-13305. [PMID: 34499066 DOI: 10.1039/d1dt02349g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of bis-cyclometalated halido(aryl) Pt(IV) complexes [PtX(Ar)(C^N)2], with C^N = cyclometalated 4-(tert-butyl)-2-phenylpyridine (bppy), 2-(p-tolyl)pyridine (tpy), 2-(2-thienyl)pyridine (thpy), or 1-phenylisoquinoline (piq), X = I, Cl, or F, and Ar = Ph (for all C^N ligands) or t-BuPh (for C^N = tpy), and the photophysical properties of the chlorido and fluorido series is reported. The oxidative addition of iodobenzene to cis-[Pt(C^N)2] precursors is demonstrated to occur in MeCN under irradiation with visible light to give complexes [PtI(Ph)(C^N)2], presumably involving radical species that also produce the activation of the solvent to give cyanomethyl complexes [PtI(CH2CN)(C^N)2]. The introduction of an aryl ligand can also be achieved by reacting cis-[Pt(C^N)2] with (Ar2I)PF6 (Ar = Ph, t-BuPh), which affords cationic intermediates of the type [Pt(Ar)(C^N)2(NCMe)]+. The subsequent addition of an iodide or chloride salt gives the corresponding iodido- or chlorido(aryl) complexes. The fluorido(aryl) derivatives can be obtained from the iodido complexes by halide exchange using AgF. The chlorido- and fluorido(aryl) complexes display intense phosphorescence in deaerated CH2Cl2 solution and poly(methyl methacrylate) (PMMA) films at 298 K from triplet excited states primarily localized on the cyclometalated ligands (3LC) with a small MLCT admixture. Compared with the chlorido complexes, the fluorido derivatives consistently present significantly shorter emission lifetimes and higher radiative and nonradiative rate constants due to a greater MLCT contribution to the emissive state. In contrast, the introduction of the t-BuPh group did not induce significant changes in radiative rates with respect to the phenyl complexes.
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Affiliation(s)
- Juan-Carlos López-López
- Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, Campus de Espinardo, 19, 30100 Murcia, Spain.
| | - Delia Bautista
- Área Científica y Técnica de Investigación, Universidad de Murcia, Campus de Espinardo, 21, 30100 Murcia, Spain
| | - Pablo González-Herrero
- Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, Campus de Espinardo, 19, 30100 Murcia, Spain.
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21
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Nair SS, Bysewski OA, Kupfer S, Wächtler M, Winter A, Schubert US, Dietzek B. Excitation Energy-Dependent Branching Dynamics Determines Photostability of Iron(II)-Mesoionic Carbene Complexes. Inorg Chem 2021; 60:9157-9173. [PMID: 34081456 DOI: 10.1021/acs.inorgchem.1c01166] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Photoactive metal complexes containing earth-abundant transition metals recently gained interest as photosensitizers in light-driven chemistry. In contrast to the traditionally employed ruthenium or iridium complexes, iron complexes developed to be promising candidates despite the fact that using iron complexes as photosensitizers poses an inherent challenge associated with the low-lying metal-centered states, which are responsible for ultrafast deactivation of the charge-transfer states. Nonetheless, recent developments of strongly σ-donating carbene ligands yielded highly promising systems, in which destabilized metal-centered states resulted in prolonged lifetimes of charge-transfer excited states. In this context, we introduce a series of novel homoleptic Fe-triazolylidene mesoionic carbene complexes. The excited-state properties of the complexes were investigated by time-resolved femtosecond transient absorption spectroscopy and quantum chemical calculations. Pump wavelength-dependent transient absorption reveals the presence of distinct excited-state relaxation pathways. We relate the excitation-wavelength-dependent branching of the excited-state dynamics into various reaction channels to solvent-dependent photodissociation following the population of dissociative metal centered states upon excitation at 400 nm.
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Affiliation(s)
- Shruthi S Nair
- Department Functional Interfaces, Leibniz Institute of Photonic Technology (Leibniz-IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Oliver A Bysewski
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany.,Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg, 07743 Jena, Germany
| | - Stephan Kupfer
- Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Maria Wächtler
- Department Functional Interfaces, Leibniz Institute of Photonic Technology (Leibniz-IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany.,Abbe Center of Photonics, Friedrich Schiller University Jena, Philosophenweg, 07745 Jena, Germany
| | - Andreas Winter
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany.,Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg, 07743 Jena, Germany
| | - Ulrich S Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich-Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany.,Center for Energy and Environmental Chemistry Jena (CEEC-Jena), Friedrich-Schiller University Jena, Philosophenweg, 07743 Jena, Germany
| | - Benjamin Dietzek
- Department Functional Interfaces, Leibniz Institute of Photonic Technology (Leibniz-IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany.,Institute of Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
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22
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Rasu L, Amiri M, Bergens SH. Carbazole-Cyanobenzene Dyes Electrografted to Carbon or Indium-Doped Tin Oxide Supports for Visible Light-Driven Photoanodes and Olefin Isomerizations. ACS APPLIED MATERIALS & INTERFACES 2021; 13:17745-17752. [PMID: 33826282 DOI: 10.1021/acsami.1c05064] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The organic carbazole-cyanobenzene push-pull dye 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene was derivatized and attached to carbon or indium-doped tin oxide (ITO) electrodes by simple diazonium electrografting. The surface-bound dye is active and stable for the visible light photosynthetic isomerization of a wide range of functionalized stilbene and cinnamic acid derivatives. Up to 87,000 net turnovers were obtained for the isomerization of trans-stilbene. The isomerizations can be carried out in air with a 33% reduction in the rate. The ITO photoelectrodes are also active and stable toward photo-oxidations under basic and acidic conditions.
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Affiliation(s)
- Loorthuraja Rasu
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
| | - Mona Amiri
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
| | - Steven H Bergens
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
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23
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Karreman S, Karnbrock SBH, Kolle S, Golz C, Alcarazo M. Synthesis of 6 H-Benzo[ c]chromene Scaffolds from O-Benzylated Phenols through a C-H Sulfenylation/Radical Cyclization Sequence. Org Lett 2021; 23:1991-1995. [PMID: 33648340 PMCID: PMC7986580 DOI: 10.1021/acs.orglett.1c00087] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
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S-Aryl dibenzothiophenium salts, obtained through a highly
regioselective C–H sulfenylation of o-benzyl-protected phenols,
are used as precursors of 6H-benzo[c]chromenes. The
reaction starts with a photocatalytically triggered single-electron transfer to the
sulfonium salt, which promotes the formation of an aryl radical via selective mesolitic
cleavage of the S–Arexo bond. Mechanistic studies reveal that this
initial radical species cyclizes following a kinetically favored 5-exo-trig pathway.
Subsequent ring expansion, favored by rearomatization, delivers the desired tricyclic
systems.
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Affiliation(s)
- Steve Karreman
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077-Göttingen, Germany
| | - Simon B H Karnbrock
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077-Göttingen, Germany
| | - Sebastian Kolle
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077-Göttingen, Germany
| | - Christopher Golz
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077-Göttingen, Germany
| | - Manuel Alcarazo
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr 2, 37077-Göttingen, Germany
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24
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Yoon S, Teets TS. Red to near-infrared phosphorescent Ir(iii) complexes with electron-rich chelating ligands. Chem Commun (Camb) 2021; 57:1975-1988. [PMID: 33538276 DOI: 10.1039/d0cc08067e] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The design of molecular phosphors with near-unity photoluminescence quantum yields in the low-energy regions of the spectrum, red to near-infrared, is a long-standing challenge. Because of the energy gap law and the quantum mechanical dependence of radiative decay rate on the excited-state energy, compounds which luminesce in this region of the spectrum typically suffer from low quantum yields. In this article, we highlight our group's advances in the design of top-performing cyclometalated iridium complexes which phosphoresce in red to near-infrared regions. The compounds we have introduced in this body of work have the general formula Ir(C^N)2(L^X), where C^N is a cyclometalating ligand that controls the photoluminescence color and L^X is a monoanionic chelating ancillary ligand. The Ir(C^N)2(L^X) structure type is among the most widely studied and technologically successful classes of molecular phosphors, particularly when L^X = acetylacetonate (acac). In our work we have pioneered the use of electron-rich, nitrogen containing ancillary (L^X) ligands as a means of controlling the excited-state dynamics and optimizing them to give record-breaking phosphorescence quantum yields. This paper progresses through our work in three distinct regions of the spectrum - red, deep-red, and near-infrared - and summarizes the many insights we have gained on the relationships between molecular structure, frontier orbital energies, and excited-state dynamics.
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Affiliation(s)
- Sungwon Yoon
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, TX 77204-5003, USA.
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25
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Teets TS, Wu Y, Kim D. Photophysical Properties and Redox Potentials of Photosensitizers for Organic Photoredox Transformations. Synlett 2021. [DOI: 10.1055/a-1390-9065] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AbstractPhotoredox catalysis has proven to be a powerful tool in synthetic organic chemistry. The rational design of photosensitizers with improved photocatalytic performance constitutes a major advancement in photoredox organic transformations. This review summarizes the fundamental ground-state and excited-state photophysical and electrochemical attributes of molecular photosensitizers, which are important determinants of their photocatalytic reactivity.
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Shon JH, Kim D, Rathnayake MD, Sittel S, Weaver J, Teets TS. Photoredox catalysis on unactivated substrates with strongly reducing iridium photosensitizers. Chem Sci 2021; 12:4069-4078. [PMID: 34163678 PMCID: PMC8179447 DOI: 10.1039/d0sc06306a] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/28/2021] [Indexed: 12/13/2022] Open
Abstract
Photoredox catalysis has emerged as a powerful strategy in synthetic organic chemistry, but substrates that are difficult to reduce either require complex reaction conditions or are not amenable at all to photoredox transformations. In this work, we show that strong bis-cyclometalated iridium photoreductants with electron-rich β-diketiminate (NacNac) ancillary ligands enable high-yielding photoredox transformations of challenging substrates with very simple reaction conditions that require only a single sacrificial reagent. Using blue or green visible-light activation we demonstrate a variety of reactions, which include hydrodehalogenation, cyclization, intramolecular radical addition, and prenylation via radical-mediated pathways, with optimized conditions that only require the photocatalyst and a sacrificial reductant/hydrogen atom donor. Many of these reactions involve organobromide and organochloride substrates which in the past have had limited utility in photoredox catalysis. This work paves the way for the continued expansion of the substrate scope in photoredox catalysis.
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Affiliation(s)
- Jong-Hwa Shon
- Department of Chemistry, University of Houston 3585 Cullen Blvd., Room 112 Houston TX 77204-5003 USA
| | - Dooyoung Kim
- Department of Chemistry, University of Houston 3585 Cullen Blvd., Room 112 Houston TX 77204-5003 USA
| | - Manjula D Rathnayake
- Department of Chemistry, Oklahoma State University 107, Physical Science Stillwater OK 74078 USA
| | - Steven Sittel
- Department of Chemistry, University of Houston 3585 Cullen Blvd., Room 112 Houston TX 77204-5003 USA
| | - Jimmie Weaver
- Department of Chemistry, Oklahoma State University 107, Physical Science Stillwater OK 74078 USA
| | - Thomas S Teets
- Department of Chemistry, University of Houston 3585 Cullen Blvd., Room 112 Houston TX 77204-5003 USA
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27
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Affiliation(s)
- Sina Witzel
- Organisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - A. Stephen K. Hashmi
- Organisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
- Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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28
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Raza A, Qumar U, Haider A, Naz S, Haider J, Ul-Hamid A, Ikram M, Ali S, Goumri-Said S, Kanoun MB. Liquid-phase exfoliated MoS 2 nanosheets doped with p-type transition metals: a comparative analysis of photocatalytic and antimicrobial potential combined with density functional theory. Dalton Trans 2021; 50:6598-6619. [PMID: 33899890 DOI: 10.1039/d1dt00236h] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
MoS2 nanosheets were developed by undertaking the liquid-phase exfoliation of bulk counterparts. In order to enhance its photocatalytic properties, the host material was doped with p-type transition metals (i.e., Ag, Co, Bi, and Zr). The hydrothermal technique was used to produce samples doped with 7.5 wt% transition metals (TM). X-ray diffraction detected the existence of 2H-phase by mirroring its reflection at 2θ ∼ 14°, while the peak distribution revealed the degree of exfoliation in samples. Low PL intensities indicated a lower recombination of electron-hole pairs, as corroborated by a high degree of photocatalytic action. Raman analysis was undertaken to identify molecular vibrations. The A1g mode in Raman spectra consistently showed a blueshift in all samples and the E12g mode was only slightly affected, which is evidence of the p-type doping in the MoS2 nanosheets. In the XPS spectrum, two characteristic peaks of Mo 3d appeared at 229.87 and 233.03 eV assigned to Mo-3d5/2 and Mo-3d3/2, respectively. Furthermore, a microstructural examination with HR-TEM and FESEM divulged a thin-layered structure of MoS2 consisting of flat, gently curved or twisted nanosheets. Diverse morphologies were observed with a non-uniform distribution of the dopant. Photocatalytic action of the TM-doped products effectively degraded methylene blue (MB) concentrations of up to 94 percent (for Ag-MoS2). The synergistic effect of doped MoS2 nanosheets against S. aureus in comparison to E. coli bacteria was also evaluated. The efficacy % age improved from (0-31.7%) and (23.5-55.2%) against E. coli, and (0-34.2%) and (8.3-69.23%) against S. aureus. Moreover, results from first principles calculations indicate that substitutional doping of TM atoms is indeed advantageous. Theoretical calculations confirmed that doping with Ag, Co, Bi, and Zr leads to a decrease in the band gap to a certain degree, in which the conduction band edge shifts toward lower energy, while the valence band shifts closer to the high energy end. It can be concluded that Ag, Co, and Bi impurities can lead to beneficial p-type doping in MoS2 monolayered structures. With regards to doping with Zr, the acceptor levels are formed above the edge of the valence band, revealing an introduction of the p-type character.
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Affiliation(s)
- Ali Raza
- Department of Physics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, 14 Ali Road, Lahore, Pakistan
| | - Usman Qumar
- Department of Physics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, 14 Ali Road, Lahore, Pakistan
| | - Ali Haider
- Department of Clinical Medicine and Surgery, University of Veterinary and Animal Sciences, Lahore 54000, Punjab, Pakistan
| | - Sadia Naz
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Junaid Haider
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Anwar Ul-Hamid
- Core Research Facilities, King Fahd University of Petroleum & Minerals, Dhahran, 31261, Saudi Arabia
| | - Muhammad Ikram
- Solar Cell Applications Research Lab, Department of Physics, Government College University Lahore, 54000, Punjab, Pakistan.
| | - Salamat Ali
- Department of Physics, Riphah Institute of Computing and Applied Sciences (RICAS), Riphah International University, 14 Ali Road, Lahore, Pakistan
| | - Souraya Goumri-Said
- College of Science, Physics Department, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia
| | - Mohammed Benali Kanoun
- Department of Physics, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa, 31982, Saudi Arabia.
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Adhikari S, Bhattacharjee T, Bhattacharjee S, Daniliuc CG, Frontera A, Lopato EM, Bernhard S. Nickel(II) complexes based on dithiolate-polyamine binary ligand systems: crystal structures, hirshfeld surface analysis, theoretical study, and catalytic activity study on photocatalytic hydrogen generation. Dalton Trans 2021; 50:5632-5643. [PMID: 33908954 DOI: 10.1039/d1dt00352f] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
To ascertain the influence of binary ligand systems [1,1-dicyanoethylene-2,2-dithiolate (i-mnt-2) and polyamine {tetraen = tris(2-aminoethyl)amine, tren = diethylene triamine and opda = o-phenylenediamine}] on the coordination modes of the Ni(ii) metal center and resulting supramolecular architectures, a series of nickel(ii) thiolate complexes [Ni(tetraen)(i-mnt)](DMSO) (1), [Ni2(tren)2(i-mnt)2] (2), and [Ni2(i-mnt)2(opda)2]n (3) have been synthesized in high yield in one step in water and structurally characterized by single crystal X-ray crystallography and spectroscopic techniques. X-ray diffraction studies disclose the diverse i-mnt-2 coordination to the Ni+2 center in the presence of active polyamine ligands, forming a slightly distorted octahedral geometry (NiN4S2) in 1, square planar (NiS4) and distorted octahedral geometries (NiN6) in the bimetallic co-crystallized aggregate of cationic [Ni(tren)2]+2 and anionic [Ni(i-mnt)2]-2 in 2, and a one dimensional (1D) polymeric chain along the [100] axis in 3, having consecutive square planar (NiS4) and octahedral (NiN6) coordination kernels. The N-HO, N-HS, N-HN, N-HS, N-HN, and N-HO type hydrogen bonds stabilize the supramolecular assemblies in 1, 2, and 3 respectively imparting interesting graph-set-motifs. The molecular Hirshfeld surface analyses (HS) and 2D fingerprint plots were utilized for decoding all types of non-covalent contacts in the crystal networks. Atomic HS analysis of the Ni+2 centers reveals significant Ni-N metal-ligand interactions compared to Ni-S interactions. We have also studied the unorthodox interactions observed in the solid state structures of 1-3 by QTAIM and NBO analyses. Moreover, all the complexes proved to be highly active water reduction co-catalysts (WRC) in a photo-catalytic hydrogen evolution process involving iridium photosensitizers, wherein 2 and 3 having a square planar arrangement around the nickel center(s) - were found to be the most active ones, achieving 1000 and 1119 turnover numbers (TON), respectively.
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Affiliation(s)
- Suman Adhikari
- Department of Chemistry, Govt. Degree College, Dharmanagar, Tripura (N)-799253, India.
| | - Tirtha Bhattacharjee
- Department of Chemistry, Bineswar Brahma Engineering College, Kokrajhar-783370, Assam, India
| | | | - Constantin Gabriel Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, D-48149, Münster, Germany
| | - Antonio Frontera
- Department de Quimica, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma de Mallorca, Baleares, Spain.
| | - Eric M Lopato
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - Stefan Bernhard
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA
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Synthesis of Magnetic Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 Nanoparticles: The Photocatalytic Effects on Organic Pollutants upon Irradiation with UV-Vis Light. Catalysts 2020. [DOI: 10.3390/catal10050494] [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] Open
Abstract
Magnetic Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 nanoparticles with different molar ratios of CeVO4 to other inorganic components were synthesized through co-precipitation with a sonochemical-assisted method. X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, vibrating sample magnetometry, and scanning electron microscopy (SEM) methods were used for the physico–chemical characterization of the obtained nanoparticles. As shown in the SEM images, the average sizes of the Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 nanoparticles that formed aggregates were approximately 50–70 nm and 80–100 nm, respectively. The photocatalytic performance of these nanoparticles was examined by measuring methylene blue degradation under visible light (assisted by H2O2). The sample with a mass ratio of 1:2:1 (Fe3O4/ZnWO4/CeVO4, S4) exhibited optimal photocatalytic performance, and thus this sample was subsequently used for the photodegradation of different organic pollutants upon irradiation with ultraviolet (UV) and visible light. Approximately 90% and 70% degradation of methyl violet and methylene blue, respectively, was observed after visible light irradiation. Additionally, the mechanism of the photocatalytic reaction was investigated by measuring ˙OH release under UV light in a system with terephthalic acid and by measuring the release of ˙O2−, ˙OH, and hole scavengers.
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