1
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East NR, Naumann R, Förster C, Ramanan C, Diezemann G, Heinze K. Oxidative two-state photoreactivity of a manganese(IV) complex using near-infrared light. Nat Chem 2024; 16:827-834. [PMID: 38332331 DOI: 10.1038/s41557-024-01446-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 01/11/2024] [Indexed: 02/10/2024]
Abstract
Highly reducing or oxidizing photocatalysts are a fundamental challenge in photochemistry. Only a few transition metal complexes with Earth-abundant metal ions have so far advanced to excited state oxidants. All these photocatalysts require high-energy light for excitation, and their oxidizing power has not been fully exploited due to energy dissipation before reaching the photoactive state. Here we demonstrate that the complex [Mn(dgpy)2]4+, based on Earth-abundant manganese and the tridentate 2,6-diguanidylpyridine ligand (dgpy), evolves to a luminescent doublet ligand-to-metal charge transfer (2LMCT) excited state (1,435 nm, 0.86 eV) with a lifetime of 1.6 ns after excitation with low-energy near-infrared light. This 2LMCT state oxidizes naphthalene to its radical cation. Substrates with extremely high oxidation potentials up to 2.4 V enable the [Mn(dgpy)2]4+ photoreduction via a high-energy quartet 4LMCT excited state with a lifetime of 0.78 ps, proceeding via static quenching by the solvent. This process minimizes free energy losses and harnesses the full photooxidizing power, and thus allows oxidation of nitriles and benzene using Earth-abundant elements and low-energy light.
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Affiliation(s)
- Nathan R East
- Department of Chemistry, Johannes Gutenberg University, Mainz, Germany
| | - Robert Naumann
- Department of Chemistry, Johannes Gutenberg University, Mainz, Germany
| | - Christoph Förster
- Department of Chemistry, Johannes Gutenberg University, Mainz, Germany
| | - Charusheela Ramanan
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Max-Planck-Institute for Polymer Research, Mainz, Germany
| | - Gregor Diezemann
- Department of Chemistry, Johannes Gutenberg University, Mainz, Germany
| | - Katja Heinze
- Department of Chemistry, Johannes Gutenberg University, Mainz, Germany.
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2
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Antolini C, Spellman CD, Otolski CJ, Doumy G, March AM, Walko DA, Liu C, Zhang X, Young BT, Goodwill JE, Hayes D. Photochemical and Photophysical Dynamics of the Aqueous Ferrate(VI) Ion. J Am Chem Soc 2022; 144:22514-22527. [PMID: 36454056 DOI: 10.1021/jacs.2c08048] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Ferrate(VI) has the potential to play a key role in future water supplies. Its salts have been suggested as "green" alternatives to current advanced oxidation and disinfection methods in water treatment, especially when combined with ultraviolet light to stimulate generation of highly oxidizing Fe(V) and Fe(IV) species. However, the nature of these intermediates, the mechanisms by which they form, and their roles in downstream oxidation reactions remain unclear. Here, we use a combination of optical and X-ray transient absorption spectroscopies to study the formation, interconversion, and relaxation of several excited-state and metastable high-valent iron species following excitation of aqueous potassium ferrate(VI) by ultraviolet and visible light. Branching from the initially populated ligand-to-metal charge transfer state into independent photophysical and photochemical pathways occurs within tens of picoseconds, with the quantum yield for the generation of reactive Fe(V) species determined by relative rates of the competing intersystem crossing and reverse electron transfer processes. Relaxation of the metal-centered states then occurs within 4 ns, while the formation of metastable Fe(V) species occurs in several steps with time constants of 250 ps and 300 ns. Results here improve the mechanistic understanding of the formation and fate of Fe(V) and Fe(IV), which will accelerate the development of novel advanced oxidation processes for water treatment applications.
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Affiliation(s)
- Cali Antolini
- Department of Chemistry, University of Rhode Island, 45 Upper College Road, Kingston, Rhode Island 02881, United States
| | - Charles D Spellman
- Department of Civil and Environmental Engineering, University of Rhode Island, 45 Upper College Road, Kingston, Rhode Island 02881, United States
| | - Christopher J Otolski
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Gilles Doumy
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Anne Marie March
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Donald A Walko
- X-ray Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Cunming Liu
- X-ray Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Xiaoyi Zhang
- X-ray Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Benjamin T Young
- Department of Physical Sciences, Rhode Island College, 600 Mt Pleasant Avenue, Providence, Rhode Island 02908, United States
| | - Joseph E Goodwill
- Department of Civil and Environmental Engineering, University of Rhode Island, 45 Upper College Road, Kingston, Rhode Island 02881, United States
| | - Dugan Hayes
- Department of Chemistry, University of Rhode Island, 45 Upper College Road, Kingston, Rhode Island 02881, United States
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3
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Dozza B, Rodrigues BM, Tisoco I, de Souza VB, Angnes L, Iglesias BA. Spectroelectrochemistry as a powerful technique for porphyrins/corroles derivatives electro-characterization: Fundamentals and some examples. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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4
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Gvozdev DA, Maksimov EG, Strakhovskaya MG, Pashchenko VZ, Rubin AB. Hybrid Complexes of Photosensitizers with Luminescent Nanoparticles: Design of the Structure. Acta Naturae 2021; 13:24-37. [PMID: 34707895 PMCID: PMC8526191 DOI: 10.32607/actanaturae.11379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/14/2021] [Indexed: 11/20/2022] Open
Abstract
Increasing the efficiency of the photodynamic action of the dyes used in photodynamic therapy is crucial in the field of modern biomedicine. There are two main approaches used to increase the efficiency of photosensitizers. The first one is targeted delivery to the object of photodynamic action, while the second one is increasing the absorption capacity of the molecule. Both approaches can be implemented by producing dye-nanoparticle conjugates. In this review, we focus on the features of the latter approach, when nanoparticles act as a light-harvesting agent and nonradiatively transfer the electronic excitation energy to a photosensitizer molecule. We will consider the hybrid photosensitizer-quantum dot complexes with energy transfer occurring according to the inductive-resonance mechanism as an example. The principle consisting in optimizing the design of hybrid complexes is proposed after an analysis of the published data; the parameters affecting the efficiency of energy transfer and the generation of reactive oxygen species in such systems are described.
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Affiliation(s)
- D. A. Gvozdev
- M.V. Lomonosov Moscow State University, Department of Biology, Moscow, 119991 Russia
| | - E. G. Maksimov
- M.V. Lomonosov Moscow State University, Department of Biology, Moscow, 119991 Russia
| | - M. G. Strakhovskaya
- M.V. Lomonosov Moscow State University, Department of Biology, Moscow, 119991 Russia
| | - V. Z. Pashchenko
- M.V. Lomonosov Moscow State University, Department of Biology, Moscow, 119991 Russia
| | - A. B. Rubin
- M.V. Lomonosov Moscow State University, Department of Biology, Moscow, 119991 Russia
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5
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6
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Magno LN, Bezerra FC, Freire LES, Guerra RA, Bakuzis AF, Gonçalves PJ. Use of Spectroscopic Techniques for Evaluating the Coupling of Porphyrins on Biocompatible Nanoparticles. A Potential System for Photodynamics, Theranostics, and Nanodrug Delivery Applications. J Phys Chem A 2017; 121:1924-1931. [PMID: 28209060 DOI: 10.1021/acs.jpca.6b10314] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Modern medicine has been searching for new and more efficient strategies for diagnostics and therapeutics applications. Considering this, porphyrin molecules have received great interest for applications in photodiagnostics and phototherapies, even as magnetic nanoparticles for drug-delivery systems and magnetic-hyperthermia therapy. Aiming to obtain a multifunctional system, which combines diagnostics with therapeutic functions on the same platform, the present study employed UV/vis absorption and fluorescence spectroscopies to evaluate the interaction between meso-tetrakis(p-sulfonatofenyl)porphyrin (TPPS) and maghemite nanoparticles (γ-Fe2O3). These spectroscopic techniques allowed us to describe the dynamics of coupling porphyrins on nanoparticles and estimate the number of 21 porphyrins per nanoparticle. Also, the binding parameters, such as the association constants (Ka = 8.89 × 105 M-1) and bimolecular quenching rate constant (kq = 2.54 × 1014 M-1 s-1) were obtained. These results suggest a static quenching process where the electrostatic attraction plays an essential role. The work shows that spectroscopic techniques are powerful tools to evaluate the coupling of organic molecules and nanoparticles. Besides, the system studied provides a relevant background for potential applications in bionanotechnology and nanomedicine, such as (1) nanodrug delivery system, (2) photodiagnostics/theranostics, and/or (3) a combined action of photodynamic and hyperthermia therapies, working in a synergetic way.
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Affiliation(s)
- Lais N Magno
- Instituto de Física and §Programa de Pós-graduação em Química, Universidade Federal de Goiás , 74690-900 Goiânia, GO, Brazil
| | - Fábio C Bezerra
- Instituto de Física and §Programa de Pós-graduação em Química, Universidade Federal de Goiás , 74690-900 Goiânia, GO, Brazil
| | - Luiz Eduardo S Freire
- Instituto de Física and §Programa de Pós-graduação em Química, Universidade Federal de Goiás , 74690-900 Goiânia, GO, Brazil
| | - Rubens A Guerra
- Instituto de Física and §Programa de Pós-graduação em Química, Universidade Federal de Goiás , 74690-900 Goiânia, GO, Brazil.,Faculdade Santa Rita de Cássia , Av. Adelina Alves Vilela, n° 393, Jd. Primavera, 75.524-680 Itumbiara, GO, Brazil
| | - Andris F Bakuzis
- Instituto de Física and §Programa de Pós-graduação em Química, Universidade Federal de Goiás , 74690-900 Goiânia, GO, Brazil
| | - Pablo J Gonçalves
- Instituto de Física and §Programa de Pós-graduação em Química, Universidade Federal de Goiás , 74690-900 Goiânia, GO, Brazil
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7
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Schaberle FA, Abreu AR, Gonçalves NPF, Sá GFF, Pereira MM, Arnaut LG. Ultrafast Dynamics of Manganese(III), Manganese(II), and Free-Base Bacteriochlorin: Is There Time for Photochemistry? Inorg Chem 2017; 56:2677-2689. [PMID: 28206747 DOI: 10.1021/acs.inorgchem.6b02871] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Manganese(III) and manganese(II) complexes of halogenated sulfonamide tetraphenylbacteriochlorins were prepared for the first time via a transmetalation reaction and shown to be stable at room temperature. The behavior of the electronic states of the paramagnetic complexes is remarkably different from those of the metal-free bacteriochlorins or diamagnetic metallobacteriochlorins. The Mn3+ complex exhibits eight electronic transitions between different states from 300 to 1100 nm, with a very prominent band (molar absorption coefficient of ca. 50000 M-1 cm-1) at 829 nm. Ultrafast transient absorption showed the formation of an excited singquintet state that decays to a tripquintet state with a femtosecond lifetime. The tripquintet state decays in 5 ps, yielding a tripseptet state with a 570 ps lifetime. The electronic absorption of the Mn2+ complex more closely resembles those of diamagnetic metallobacteriochlorins, but the longest decay lifetime is only ca. 8 ps. The intense photoacoustic waves generated with near-infrared excitation suggest the use of these complexes in photoacoustic tomography.
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Affiliation(s)
- Fabio A Schaberle
- Luzitin SA, Ed. Bluepharma , S. Martinho do Bispo, 3045-016 Coimbra, Portugal.,Chemistry Department, University of Coimbra , 3004-535 Coimbra, Portugal
| | - Artur R Abreu
- Luzitin SA, Ed. Bluepharma , S. Martinho do Bispo, 3045-016 Coimbra, Portugal
| | - Nuno P F Gonçalves
- Luzitin SA, Ed. Bluepharma , S. Martinho do Bispo, 3045-016 Coimbra, Portugal
| | - Gonçalo F F Sá
- LaserLeap SA, IPN , R. Pedro Nunes, 3030-199 Coimbra, Portugal
| | - Mariette M Pereira
- Chemistry Department, University of Coimbra , 3004-535 Coimbra, Portugal
| | - Luís G Arnaut
- Chemistry Department, University of Coimbra , 3004-535 Coimbra, Portugal
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8
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Jung J, Neu HM, Leeladee P, Siegler MA, Ohkubo K, Goldberg DP, Fukuzumi S. Photocatalytic Oxygenation of Substrates by Dioxygen with Protonated Manganese(III) Corrolazine. Inorg Chem 2016; 55:3218-28. [PMID: 26974004 PMCID: PMC4893963 DOI: 10.1021/acs.inorgchem.5b02019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
UV-vis spectral titrations of a manganese(III) corrolazine complex [Mn(III)(TBP8Cz)] with HOTf in benzonitrile (PhCN) indicate mono- and diprotonation of Mn(III)(TBP8Cz) to give Mn(III)(OTf)(TBP8Cz(H)) and [Mn(III)(OTf)(H2O)(TBP8Cz(H)2)][OTf] with protonation constants of 9.0 × 10(6) and 4.7 × 10(3) M(-1), respectively. The protonated sites of Mn(III)(OTf)(TBP8Cz(H)) and [Mn(III)(OTf)(H2O)(TBP8Cz(H)2)][OTf] were identified by X-ray crystal structures of the mono- and diprotonated complexes. In the presence of HOTf, the monoprotonated manganese(III) corrolazine complex [Mn(III)(OTf)(TBP8Cz(H))] acts as an efficient photocatalytic catalyst for the oxidation of hexamethylbenzene and thioanisole by O2 to the corresponding alcohol and sulfoxide with 563 and 902 TON, respectively. Femtosecond laser flash photolysis measurements of Mn(III)(OTf)(TBP8Cz(H)) and [Mn(III)(OTf)(H2O)(TBP8Cz(H)2)][OTf] in the presence of O2 revealed the formation of a tripquintet excited state, which was rapidly converted to a tripseptet excited state. The tripseptet excited state of Mn(III)(OTf)(TBP8Cz(H)) reacted with O2 with a diffusion-limited rate constant to produce the putative Mn(IV)(O2(•-))(OTf)(TBP8Cz(H)), whereas the tripseptet excited state of [Mn(III)(OTf)(H2O)(TBP8Cz(H)2)][OTf] exhibited no reactivity toward O2. In the presence of HOTf, Mn(V)(O)(TBP8Cz) can oxidize not only HMB but also mesitylene to the corresponding alcohols, accompanied by regeneration of Mn(III)(OTf)(TBP8Cz(H)). This thermal reaction was examined for a kinetic isotope effect, and essentially no KIE (1.1) was observed for the oxidation of mesitylene-d12, suggesting a proton-coupled electron transfer (PCET) mechanism is operative in this case. Thus, the monoprotonated manganese(III) corrolazine complex, Mn(III)(OTf)(TBP8Cz(H)), acts as an efficient photocatalyst for the oxidation of HMB by O2 to the alcohol.
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Affiliation(s)
- Jieun Jung
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea
| | - Heather M. Neu
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Pannee Leeladee
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Maxime A. Siegler
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Kei Ohkubo
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA and SENTAN, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan
| | - David P. Goldberg
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA and SENTAN, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan
- Faculty of Science and Engineering, Meijo University, ALCA and SEN TAN, Japan Science and Technology Agency (JST), Nagoya, Aichi 468-0073, Japan
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9
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Fukuzumi S. Electron transfer and catalysis with high-valent metal-oxo complexes. Dalton Trans 2015; 44:6696-705. [DOI: 10.1039/c5dt00204d] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
High-valent metal-oxo complexes are produced by thermal and photoinduced electron-transfer reactions, acting as catalysts for oxygenation of substrates using water or dioxygen as an oxygen source.
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Affiliation(s)
- Shunichi Fukuzumi
- Department of Material and Life Science
- Division of Advanced Science and Biotechnology
- Graduate School of Engineering
- Osaka University
- ALCA
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10
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Jung J, Ohkubo K, Goldberg DP, Fukuzumi S. Photocatalytic oxygenation of 10-methyl-9,10-dihydroacridine by O₂ with manganese porphyrins. J Phys Chem A 2014; 118:6223-9. [PMID: 25079061 PMCID: PMC4136676 DOI: 10.1021/jp505860f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
![]()
Photocatalytic
oxygenation of 10-methyl-9,10-dihydroacridine (AcrH2) by
dioxygen (O2) with a manganese porphyrin [(P)MnIII: 5,10,15,20-tetrakis-(2,4,6-trimethylphenyl)porphinatomanganese(III)
hydroxide [(TMP)MnIII(OH)] (1) or 5,10,15,20-tetrakis(pentafluorophenyl)porphyrinatomanganese(III)
acetate [(TPFPP)MnIII(CH3COO)] (2)] occurred to yield 10-methyl-(9,10H)-acridone
(Acr=O) in an oxygen-saturated benzonitrile (PhCN) solution
under visible light irradiation. The photocatalytic reactivity of
(P)MnIII in the presence of O2 is in proportion
to concentrations of AcrH2 or O2 with the maximum
turnover numbers of 17 and 6 for 1 and 2, respectively. The quantum yield with 1 was determined
to be 0.14%. Deuterium kinetic isotope effects (KIEs) were observed
with KIE = 22 for 1 and KIE = 6 for 2, indicating
that hydrogen-atom transfer from AcrH2 is involved in the
rate-determining step of the photocatalytic reaction. Femtosecond transient absorption measurements are consistent with photoexcitation of (P)MnIII, resulting in intersystem crossing from a tripquintet excited state to a tripseptet excited state. A mechanism is proposed where the tripseptet excited state reacts with O2 to produce a putative (P)MnIV superoxo complex. Hydrogen-atom transfer from AcrH2 to (P)MnIV(O2•–) generating a hydroperoxo complex (P)MnIV(OOH) and AcrH• is likely the rate-determining step, in competition with back electron transfer to regenerate the ground state (P)MnIII and O2. The subsequent reductive O–O bond cleavage by AcrH• may occur rapidly inside of the reaction cage to produce (P)MnV(O) and AcrH(OH), followed by the oxidation of AcrH(OH) by
(P)MnV(O) to yield Acr=O with regeneration of (P)MnIII.
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Affiliation(s)
- Jieun Jung
- Department of Material and Life Science, Graduate School of Engineering, Osaka University and ALCA, Japan Science and Technology Agency (JST) , 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
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11
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Jung J, Ohkubo K, Prokop-Prigge KA, Neu HM, Goldberg DP, Fukuzumi S. Photochemical oxidation of a manganese(III) complex with oxygen and toluene derivatives to form a manganese(V)-oxo complex. Inorg Chem 2013; 52:13594-604. [PMID: 24219426 PMCID: PMC3875180 DOI: 10.1021/ic402121j] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Visible light photoirradiation of an oxygen-saturated benzonitrile solution of a manganese(III) corrolazine complex [(TBP8Cz)Mn(III)] (1): [TBP8Cz = octakis(p-tert-butylphenyl)corrolazinato(3-)] in the presence of toluene derivatives resulted in formation of the manganese(V)-oxo complex [(TBP8Cz)Mn(V)(O)]. The photochemical oxidation of (TBP8Cz)Mn(III) with O2 and hexamethylbenzene (HMB) led to the isosbestic conversion of 1 to (TBP8Cz)Mn(V)(O), accompanied by the selective oxidation of HMB to pentamethylbenzyl alcohol (87%). The formation rate of (TBP8Cz)Mn(V)(O) increased with methyl group substitution, from toluene, p-xylene, mesitylene, durene, pentamethylbenzene, up to hexamethylbenzene. Deuterium kinetic isotope effects (KIEs) were observed for toluene (KIE = 5.4) and mesitylene (KIE = 5.3). Femtosecond laser flash photolysis of (TBP8Cz)Mn(III) revealed the formation of a tripquintet excited state, which was rapidly converted to a tripseptet excited state. The tripseptet excited state was shown to be the key, activated state that reacts with O2 via a diffusion-limited rate constant. The data allow for a mechanism to be proposed in which the tripseptet excited state reacts with O2 to give the putative (TBP8Cz)Mn(IV)(O2(•-)), which then abstracts a hydrogen atom from the toluene derivatives in the rate-determining step. The mechanism of hydrogen abstraction is discussed by comparison of the reactivity with the hydrogen abstraction from the same toluene derivatives by cumylperoxyl radical. Taken together, the data suggest a new catalytic method is accessible for the selective oxidation of C-H bonds with O2 and light, and the first evidence for catalytic oxidation of C-H bonds was obtained with 10-methyl-9,10-dihydroacridine as a substrate.
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Affiliation(s)
- Jieun Jung
- Department of Material and Life Science, Graduate School of Engineering, ALCA, Japan Science and Technology Agency, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kei Ohkubo
- Department of Material and Life Science, Graduate School of Engineering, ALCA, Japan Science and Technology Agency, Osaka University, Suita, Osaka 565-0871, Japan
| | | | - Heather M. Neu
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David P. Goldberg
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, ALCA, Japan Science and Technology Agency, Osaka University, Suita, Osaka 565-0871, Japan
- Department of Bioinspired Science, Ewha Womans University, Seoul 120-750, Korea
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12
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Gonçalves PJ, Corrêa DS, Franzen PL, De Boni L, Almeida LM, Mendonça CR, Borissevitch IE, Zílio SC. Effect of interaction with micelles on the excited-state optical properties of zinc porphyrins and J-aggregates formation. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 112:309-317. [PMID: 23685798 DOI: 10.1016/j.saa.2013.04.065] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2012] [Revised: 03/27/2013] [Accepted: 04/14/2013] [Indexed: 06/02/2023]
Abstract
This work reports on the photophysical properties of zinc porphyrins meso-tetrakis methylpyridiniumyl (Zn(2+)TMPyP) and meso-tetrakis sulfonatophenyl (Zn(2+)TPPS) in homogeneous aqueous solutions and in the presence of sodium dodecyl sulfate (SDS) and cetyltrimethyl ammonium bromide (CTAB) micelles. The excited-state dynamic was investigated with the Z-scan technique, UV-Vis absorption, and fluorescence spectroscopy. Photophysical parameters were obtained by analyzing the experimental data with a conventional five-energy-level diagram. The interaction of the charged side porphyrin groups with oppositely charged surfactants can reduce the electrostatic repulsion between porphyrin molecules leading to aggregation, which affected the porphyrin characteristics such as absorption cross-sections, lifetimes and quantum yields. The interaction between anionic ZnTPPS with cationic CTAB micelles induced the formation of porphyrin J-aggregates, while this effect was not observed in the interaction of ZnTMPyP with SDS micelles. This difference is, probably, due to the difference in electrostatic repulsion between the porphyrin molecules. The insights obtained by these results are important for the understanding of the photophysical behavior of porphyrins, regarding potential applications in pharmacokinetics as encapsulation of photosensitizer for drug delivery systems and in its interaction with cellular membrane.
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Affiliation(s)
- P J Gonçalves
- Instituto de Física, Universidade Federal de Goiás, Caixa Postal 131, 74001-970 Goiânia, GO, Brazil.
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13
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Venkatramaiah N, Ramakrishna B, Venkatesan R, Almeida Paz FA, Tomé JPC. Facile synthesis of highly stable BF3-induced meso-tetrakis (4-sulfonato phenyl) porphyrin (TPPS4)-J-aggregates: structure, photophysical and electrochemical properties. NEW J CHEM 2013. [DOI: 10.1039/c3nj00482a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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14
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Gonçalves PJ, Franzen PL, Correa DS, Almeida LM, Takara M, Ito AS, Zílio SC, Borissevitch IE. Effects of environment on the photophysical characteristics of mesotetrakis methylpyridiniumyl porphyrin (TMPyP). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:1532-1539. [PMID: 21641855 DOI: 10.1016/j.saa.2011.05.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2011] [Revised: 05/07/2011] [Accepted: 05/11/2011] [Indexed: 05/30/2023]
Abstract
Porphyrins are an important class of organic molecules, with interesting linear and nonlinear optical properties given mainly by their extended π-conjugation structure. Their photophysical properties can be greatly affected by the surrounding environment, which can be used to tune its final properties. Here we report on an experimental study of the photophysical properties of meso-tetrakis (methylpyridiniumyl) porphyrin (TMPyP) in aqueous and in several organic solvents and its interaction with micelles formed from negatively charged sodium dodecylsulphate (SDS), positively charged cetyl trimethyl ammonium bromide (CTAB) and neutral TRITON X-100. By using the Z-scan technique, flash-photolysis and time-resolved fluorescence techniques, we were able to evaluate the excited state dynamics of the TMPyP, and observed that the tetrapyrrole ring plays important role due to hydrogen bonds formation between nitrogen atom and water, while the side groups determine the porphyrin localization in non-aqueous micelle part.
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Affiliation(s)
- P J Gonçalves
- Instituto de Física, Universidade Federal de Goiás, Caixa Postal 131, 74001-970 Goiânia, GO, Brazil.
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De Boni L, Franzen PL, Gonçalves PJ, Borissevitch IE, Misoguti L, Mendonça CR, Zilio SC. Pulse train fluorescence technique for measuring triplet state dynamics. OPTICS EXPRESS 2011; 19:10813-23. [PMID: 21643338 DOI: 10.1364/oe.19.010813] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We report on a method to study the dynamics of triplet formation based on the fluorescence signal produced by a pulse train. Basically, the pulse train acts as sequential pump-probe pulses that precisely map the excited-state dynamics in the long time scale. This allows characterizing those processes that affect the population evolution of the first excited singlet state, whose decay gives rise to the fluorescence. The technique was proven to be valuable to measure parameters of triplet formation in organic molecules. Additionally, this single beam technique has the advantages of simplicity, low noise and background-free signal detection.
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Affiliation(s)
- Leonardo De Boni
- Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos, SP, Brasil.
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De Boni L, Toro C, Hernandez FE. Excited State Absorption Study in Hematoporphyrin IX. J Fluoresc 2009; 20:197-202. [DOI: 10.1007/s10895-009-0538-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Accepted: 08/27/2009] [Indexed: 11/28/2022]
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Effect of protonation on the singlet–singlet excited-state absorption of meso-tetrakis(p-sulphonatophenyl) porphyrin. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2008.12.067] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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