1
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Herder JA, Kruse SJ, Nicholas AD, Forbes TZ, Walter ED, Cho H, Cahill CL. Systematic Study of Solid-State U(VI) Photoreactivity: Long-Lived Radicalization and Electron Transfer in Uranyl Tetrachloride. Inorg Chem 2024; 63:4957-4971. [PMID: 38437845 DOI: 10.1021/acs.inorgchem.3c04144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
Reported are the syntheses, structural characterizations, and luminescence properties of three novel [UO2Cl4]2- bearing compounds containing substituted 1,1'-dialkyl-4,4'-bipyridinum dications (i.e., viologens). These compounds undergo photoinduced luminescence quenching upon exposure to UV radiation. This reactivity is concurrent with two phenomena: radicalization of the uranyl tetrachloride anion and photoelectron transfer to the viologen which constitutes the formal transfer of one electron from [UO2Cl4]2- to the viologen species. This behavior is elucidated using electron paramagnetic resonance (EPR) spectroscopy and further probed through a series of characterization and computational techniques including Rehm-Weller analysis, time-dependent density functional theory (TD-DFT), and density of states (DOS). This work provides a systematic study of the photoreactivity of the uranyl unit in the solid state, an under-described aspect of fundamental uranyl chemistry.
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Affiliation(s)
- Jordan A Herder
- Department of Chemistry, The George Washington University, 800 22nd Street, NW, Washington, District of Columbia 20052, United States
| | - Samantha J Kruse
- Department of Chemistry, University of Iowa, Chemistry Building W374, Iowa City, Iowa 55242, United States
| | - Aaron D Nicholas
- Department of Chemistry, The George Washington University, 800 22nd Street, NW, Washington, District of Columbia 20052, United States
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States
| | - Tori Z Forbes
- Department of Chemistry, University of Iowa, Chemistry Building W374, Iowa City, Iowa 55242, United States
| | - Eric D Walter
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States
| | - Herman Cho
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States
| | - Christopher L Cahill
- Department of Chemistry, The George Washington University, 800 22nd Street, NW, Washington, District of Columbia 20052, United States
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2
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Zhu F, Kong L, He M, Fang D, Hu X, Peng X. Effective reduction and recovery of As(III) and As(V) from alkaline wastewater by thiourea dioxide: Efficiency and mechanism. WATER RESEARCH 2023; 243:120355. [PMID: 37506638 DOI: 10.1016/j.watres.2023.120355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/25/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023]
Abstract
For alkaline wastewater with high arsenic concentration, the traditional lime precipitation inevitably produces large amounts of hazardous waste. Herein, a heat-activated reduction method employing thiourea dioxide (TDO) as the reductant was proposed to efficiently remove and recover As(III)/As(V) from alkaline wastewater in the form of valuable As(0). More than 99.9% of As(III)/As(V) (2-400 mM) were reduced to As(0) with a high purity of more than 99.5 wt% by TDO within 30 min. The highly reductive eaq- and SO2- radical generated during TDO decomposition contribute to the arsenic reduction, and the contribution ratios of eaq- and SO2- radical were estimated to be approximately 57.6% and 42.4% for As(III) removal and 62.2% and 37.8% for As(V) removal, respectively. The arsenic reduction was greatly improved by increasing pH and temperature, which could accelerate the cleavage of C-S bond in TDO for the eaq- and SO2- formation. The presence of dissolved oxygen, which can not only scavenge eaq-/SO2- but also directly oxidize SO22-, had a negative effect on the arsenic removal. The presence of CO32- slightly suppressed the arsenic removal due to the eaq- scavenging effect while SiO32-, PO43-, Cl-, SO42- and NH4+ had negligible effects. The proposed method was a potential technology for the efficient removal and reduction of arsenic in alkaline wastewater.
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Affiliation(s)
- Feng Zhu
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Linghao Kong
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Mengchang He
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Duxian Fang
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xingyun Hu
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xianjia Peng
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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3
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Antoni PW, Golz C, Hansmann MM. Organic Four-Electron Redox Systems Based on Bipyridine and Phenanthroline Carbene Architectures. Angew Chem Int Ed Engl 2022; 61:e202203064. [PMID: 35298870 PMCID: PMC9325510 DOI: 10.1002/anie.202203064] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Indexed: 12/14/2022]
Abstract
Novel organic redox systems that display multistage redox behaviour are highly sought-after for a series of applications such as organic batteries or electrochromic materials. Here we describe a simple strategy to transfer well-known two-electron redox active bipyridine and phenanthroline architectures into novel strongly reducing four-electron redox systems featuring fully reversible redox events with up to five stable oxidation states. We give spectroscopic and structural insight into the changes involved in the redox-events and present characterization data on all isolated oxidation states. The redox-systems feature strong UV/Vis/NIR polyelectrochromic properties such as distinct strong NIR absorptions in the mixed valence states. Two-electron charge-discharge cycling studies indicate high electrochemical stability at strongly negative potentials, rendering the new redox architectures promising lead structures for multi-electron anolyte materials.
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Affiliation(s)
- Patrick W Antoni
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str.6, 44227, Dortmund, Germany
| | - Christopher Golz
- Georg-August Universität Göttingen, Institut für Organische und Biomolekulare Chemie, Tammannstr. 2, 37077, Göttingen, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str.6, 44227, Dortmund, Germany
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4
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Antoni PW, Golz C, Hansmann MM. Organic Four‐Electron Redox Systems Based on Bipyridine and Phenanthroline Carbene Architectures. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Patrick W. Antoni
- TU Dortmund: Technische Universitat Dortmund Fakultät für Chemie und Chemische Biologie GERMANY
| | - Christopher Golz
- Georg-August-Universität Göttingen: Georg-August-Universitat Gottingen Institut für Organische und Biomolekulare Chemie GERMANY
| | - Max M. Hansmann
- TU Dortmund: Technische Universitat Dortmund Fakultät für Chemie und Chemische Biologie Otto-Hahn Str.6 44227 Dortmund GERMANY
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5
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Liu F, Chowdhury S, Rosas R, Monnier V, Charles L, Karoui H, Gigmes D, Ouari O, Chevallier F, Bucher C, Kermagoret A, Liu S, Bardelang D. Triple Stack of a Viologen Derivative in a CB[10] Pair. Org Lett 2021; 23:5283-5287. [PMID: 33851849 DOI: 10.1021/acs.orglett.1c00773] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A viologen-phenylene-imidazole (VPI) conjugate, previously shown to be singly complexed by CB[7] and doubly bound by CB[8], is herein shown to form antiparallel triple stacks in water with cucurbit[10]uril (CB[10]), pairwise complexing the guest trimer. The quinary host:guest 2:3 complex showed features assignable to charge-transfer interactions. Under reductive conditions, CB[10] could solubilize a VPI radical, even though CB[10] and reduced VPI are almost insoluble, thereby illustrating a possible new application for CB[10].
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Affiliation(s)
- Fengbo Liu
- The State Key Laboratory of Refractories and Metallurgy, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China
| | - Shagor Chowdhury
- Université de Lyon, École Normale Supérieure de Lyon, CNRS UMR 5182, Laboratoire de Chimie, 46 allée d'Italie, F69364 Lyon, France
| | - Roselyne Rosas
- Aix Marseille Univ, CNRS, Spectropole, FR 1739, Marseille, France
| | - Valérie Monnier
- Aix Marseille Univ, CNRS, Spectropole, FR 1739, Marseille, France
| | | | - Hakim Karoui
- Aix Marseille Univ, CNRS, ICR, Marseille, France
| | | | | | - Floris Chevallier
- Université de Lyon, École Normale Supérieure de Lyon, CNRS UMR 5182, Laboratoire de Chimie, 46 allée d'Italie, F69364 Lyon, France
| | - Christophe Bucher
- Université de Lyon, École Normale Supérieure de Lyon, CNRS UMR 5182, Laboratoire de Chimie, 46 allée d'Italie, F69364 Lyon, France
| | | | - Simin Liu
- The State Key Laboratory of Refractories and Metallurgy, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China
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6
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Koehler P, Lawson T, Neises J, Willkomm J, Martindale BCM, Hutton GAM, Antón-García D, Lage A, Gentleman AS, Frosz MH, Russell PSJ, Reisner E, Euser TG. Optofluidic Photonic Crystal Fiber Microreactors for In Situ Studies of Carbon Nanodot-Driven Photoreduction. Anal Chem 2021; 93:895-901. [PMID: 33315379 DOI: 10.1021/acs.analchem.0c03546] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Performing quantitative in situ spectroscopic analysis on minuscule sample volumes is a common difficulty in photochemistry. To address this challenge, we use a hollow-core photonic crystal fiber (HC-PCF) that guides light at the center of a microscale liquid channel and acts as an optofluidic microreactor with a reaction volume of less than 35 nL. The system was used to demonstrate in situ optical detection of photoreduction processes that are key components of many photocatalytic reaction schemes. The photoreduction of viologens (XV2+) to the radical XV•+ in a homogeneous mixture with carbon nanodot (CND) light absorbers is studied for a range of different carbon dots and viologens. Time-resolved absorption spectra, measured over several UV irradiation cycles, are interpreted with a quantitative kinetic model to determine photoreduction and photobleaching rate constants. The powerful combination of time-resolved, low-volume absorption spectroscopy and kinetic modeling highlights the potential of optofluidic microreactors as a highly sensitive, quantitative, and rapid screening platform for novel photocatalysts and flow chemistry in general.
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Affiliation(s)
- Philipp Koehler
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom.,Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Takashi Lawson
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom.,Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Julian Neises
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Janina Willkomm
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Benjamin C M Martindale
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Georgina A M Hutton
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Daniel Antón-García
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Ava Lage
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Alexander S Gentleman
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Michael H Frosz
- Max Planck Institute for the Science of Light, Staudtstr. 2, 91058 Erlangen, Germany
| | - Philip St J Russell
- Max Planck Institute for the Science of Light, Staudtstr. 2, 91058 Erlangen, Germany
| | - Erwin Reisner
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Tijmen G Euser
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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7
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Papadakis R. Mono- and Di-Quaternized 4,4'-Bipyridine Derivatives as Key Building Blocks for Medium- and Environment-Responsive Compounds and Materials. Molecules 2019; 25:molecules25010001. [PMID: 31861256 PMCID: PMC6982771 DOI: 10.3390/molecules25010001] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/13/2019] [Accepted: 12/16/2019] [Indexed: 01/20/2023] Open
Abstract
Mono- and di-quaternized 4,4'-bipyridine derivatives constitute a family of heterocyclic compounds, which in recent years have been employed in numerous applications. These applications correspond to various disciplines of research and technology. In their majority, two key features of these 4,4'-bipyridine-based derivatives are exploited: their redox activity and their electrochromic aptitude. Contemporary materials and compounds encompassing these skeletons as building blocks are often characterized as multifunctional, as their presence often gives rise to interesting phenomena, e.g., various types of chromism. This research trend is acknowledged, and, in this review article, recent examples of multifunctional chromic materials/compounds of this class are presented. Emphasis is placed on solvent-/medium- and environment-responsive 4,4'-bipyridine derivatives. Two important classes of 4,4'-bipyridine-based products with solvatochromic and/or environment-responsive character are reviewed: viologens (i.e., N,N'-disubstituted derivatives) and monoquats (i.e., monosubstituted 4,4'-bipyridine derivatives). The multifunctional nature of these derivatives is analyzed and structure-property relations are discussed in connection to the role of these derivatives in various novel applications.
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Affiliation(s)
- Raffaello Papadakis
- School of Chemical Engineering, National Technical University of Athens (NTUA), Laboratory of Organic Chemistry, 15780 Athens, Greece; ; Tel.: +46-728-368-595
- Department of Chemistry—Ångström Laboratory, Uppsala University, 751 20 Uppsala, Sweden
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8
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Capparelli C, Fernandez Pulido CR, Lopez-Hallman R, Geise GM, Hickner MA. Anion Exchange Membranes with Dynamic Redox-Responsive Properties. ACS APPLIED MATERIALS & INTERFACES 2019; 11:29187-29194. [PMID: 31271286 DOI: 10.1021/acsami.9b04622] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Redox-responsive anion exchange membranes were developed using photoinitiated free-radical polymerization and reversible oxidation and reduction of viologen. The membranes were formulated using poly(ethylene glycol diacrylate) and diurethane dimethacrylate oligomers, dipentaerythritol penta-/hexa-acrylate cross-linker, photoinitiators, and 4-vinylbenzyl chloride as precursors for functionalization. In the membrane, 4,4'-bipyridine reacted with the 4-vinylbenzyl chloride residues, and subsequently, unreacted amines were methylated with iodomethane to obtain viologen as both the ion carrier and redox-responsive group. Upon oxidation, viologen supports two cations, where the reduced form only contains one cation. Thus, the redox responsiveness changed the membrane ionicity by a factor of 2. The area-specific resistance of the membranes in the oxidized, +2, state was lower than in the reduced, +1, state. The resistance increased between 40.6 ± 0.1 and 111.6 ± 0.1%, depending on membrane thickness, with the most significant increment being a resistance change from 4.88 × 10-4 Ω m2 in the oxidized state to 1.03 × 10-3 Ω m2 in the reduced state. Membrane permselectivity in the reduced, +1, state was between 15.9 ± 0.1 and 26.5 ± 0.01% lower than in the oxidized, +2, state, with no change in water uptake, spanning an average of 0.87 ± 0.02 in the oxidized state to an average of 0.7 ± 0.01 in the reduced state. Upon reduction, membrane ion-exchange capacity decreases, increasing ionic resistance and decreasing membrane permselectivity due to a reduction in fixed charge concentration without a measurable change in water uptake. This trend is not generally observed for ion-exchange membranes and explains that the changes in transport properties result from changes in ionicity, not water uptake or domain size. The reversibility and stability of the stimuli responsiveness were confirmed by the absence of transport property changes after redox cycling.
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Affiliation(s)
| | | | | | - Geoffrey M Geise
- Department of Chemical Engineering , University of Virginia , Charlottesville , Virginia 22904 , United States
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9
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Kishimoto F, Matsuhisa M, Imai T, Mochizuki D, Tsubaki S, Maitani MM, Suzuki E, Wada Y. Remote Control of Electron Transfer Reaction by Microwave Irradiation: Kinetic Demonstration of Reduction of Bipyridine Derivatives on Surface of Nickel Particle. J Phys Chem Lett 2019; 10:3390-3394. [PMID: 31050903 DOI: 10.1021/acs.jpclett.9b00629] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Microwave irradiation has great potential to control chemical reactions remotely, particularly reactions that involve electron transfer. In this study, we found that the reduction reaction of bipyridine derivatives on metal nickel particles was accelerated or decelerated by 2.45 GHz microwaves without an alteration of the reaction temperature. The order of the extent of the microwave acceleration of the electron transfer reaction coincided with the negativity of the redox potential of the bipyridine derivatives, i.e., the electron transfer with smaller Δ G was significantly enhanced by microwave irradiation. By applying Marcus' electron transfer theory, we propose two mechanisms of the microwave effect on electron transfer reactions, i.e., vibration of the electrons in Ni particles to make the electron transfer easier and rotation of the water molecules to prevent the reorganization of the hydrated systems after the electron transfer reaction.
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Affiliation(s)
- Fuminao Kishimoto
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Masayuki Matsuhisa
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Takashi Imai
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Dai Mochizuki
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Shuntaro Tsubaki
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Masato M Maitani
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Eiichi Suzuki
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Yuji Wada
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1, Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
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10
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Huang J, de Nijs B, Cormier S, Sokolowski K, Grys DB, Readman CA, Barrow SJ, Scherman OA, Baumberg JJ. Plasmon-induced optical control over dithionite-mediated chemical redox reactions. Faraday Discuss 2019; 214:455-463. [PMID: 30865195 DOI: 10.1039/c8fd00155c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
External-stimuli controlled reversible formation of radical species is of great interest for synthetic and supramolecular chemistry, molecular machinery, as well as emerging technologies ranging from (photo)catalysis and photovoltaics to nanomedicine. Here we show a novel hybrid colloidal system for light-driven reversible reduction of chemical species that, on their own, do not respond to light. This is achieved by the unique combination of photo-sensitive plasmonic aggregates and temperature-responsive inorganic species generating radicals that can be finally accepted and stabilised by non-photo-responsive organic molecules. In this system Au nanoparticles (NPs) self-assembled via sub-nm precise molecular spacers (cucurbit[n]urils) interact strongly with visible light to locally accelerate the decomposition of dithionite species (S2O42-) close to the NP interfaces. This light-driven process leads to the generation of inorganic radicals whose electrons can then be reversibly picked up by small organic acceptors, such as the methyl viologen molecules (MV2+) used here. During light-triggered plasmon- and heat-assisted generation of radicals, the S2O42- species work as a chemical 'fuel' linking photo-induced processes at the NP interfaces with redox chemistry in the surrounding water environment. By incorporating MV2+ as a Raman-active reporter molecule, the resulting optically-controlled redox processes can be followed in real-time.
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Affiliation(s)
- Junyang Huang
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thompson Avenue, Cambridge, CB3 0HE, UK.
| | - Bart de Nijs
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thompson Avenue, Cambridge, CB3 0HE, UK.
| | - Sean Cormier
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thompson Avenue, Cambridge, CB3 0HE, UK.
| | - Kamil Sokolowski
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - David-Benjamin Grys
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thompson Avenue, Cambridge, CB3 0HE, UK.
| | - Charlie A Readman
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Steven J Barrow
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Oren A Scherman
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Jeremy J Baumberg
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thompson Avenue, Cambridge, CB3 0HE, UK.
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11
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de Nijs B, Benz F, Barrow SJ, Sigle DO, Chikkaraddy R, Palma A, Carnegie C, Kamp M, Sundararaman R, Narang P, Scherman OA, Baumberg JJ. Plasmonic tunnel junctions for single-molecule redox chemistry. Nat Commun 2017; 8:994. [PMID: 29057870 PMCID: PMC5714966 DOI: 10.1038/s41467-017-00819-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 07/25/2017] [Indexed: 12/29/2022] Open
Abstract
Nanoparticles attached just above a flat metallic surface can trap optical fields in the nanoscale gap. This enables local spectroscopy of a few molecules within each coupled plasmonic hotspot, with near thousand-fold enhancement of the incident fields. As a result of non-radiative relaxation pathways, the plasmons in such sub-nanometre cavities generate hot charge carriers, which can catalyse chemical reactions or induce redox processes in molecules located within the plasmonic hotspots. Here, surface-enhanced Raman spectroscopy allows us to track these hot-electron-induced chemical reduction processes in a series of different aromatic molecules. We demonstrate that by increasing the tunnelling barrier height and the dephasing strength, a transition from coherent to hopping electron transport occurs, enabling observation of redox processes in real time at the single-molecule level.
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Affiliation(s)
- Bart de Nijs
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Ave, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Felix Benz
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Ave, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Steven J Barrow
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Daniel O Sigle
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Ave, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Rohit Chikkaraddy
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Ave, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Aniello Palma
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Cloudy Carnegie
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Ave, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Marlous Kamp
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Ravishankar Sundararaman
- Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy,, 12180, NY, USA
| | - Prineha Narang
- John A. Paulson School of Engineering and Applied Sciences, Faculty of Arts and Sciences, Harvard University, Cambridge,, 02138, MA, USA
| | - Oren A Scherman
- Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Jeremy J Baumberg
- NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Ave, University of Cambridge, Cambridge, CB3 0HE, UK.
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12
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Marchini M, Baroncini M, Bergamini G, Ceroni P, D'Angelantonio M, Franchi P, Lucarini M, Negri F, Szreder T, Venturi M. Hierarchical Growth of Supramolecular Structures Driven by Pimerization of Tetrahedrally Arranged Bipyridinium Units. Chemistry 2017; 23:6380-6390. [PMID: 28263437 DOI: 10.1002/chem.201700137] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Indexed: 11/09/2022]
Abstract
A shape-persistent molecule, featuring four bipyridinium units, has been synthesized that upon reduction undergoes intermolecular pimerization because of the rigid architecture of the molecule. The pimerization process has been investigated by a variety of techniques, such as absorption measurements, EPR spectroscopy, as well as gamma and pulse radiolysis, and compared with the behavior of a model compound. Computational studies have also been performed to support the experimental data. The most interesting feature of the tetramer is that pimerization occurs only above a threshold concentration of monoreduced species, on the contrary to the model compound. Furthermore, there is an increase of the apparent pimerization constant by increasing the concentration of reduced bipyridinium units. These results have been interpreted by the fact that pimerization is favored in the tetrahedrally shaped molecule because of a cooperative mechanism. Each multiply reduced molecule can indeed undergo multiple intermolecular interactions that enhance the stabilization of the system, also leading to hierarchical supramolecular growth. The resulting supramolecular system formed by such intermolecular pimerization should exhibit a diamond-like structure, as suggested by a simplified modeling approach. The intermolecular nature of the pimerization process occurring in the tetramer has been demonstrated by measuring the corresponding bimolecular rate constant by pulsed radiolysis experiments.
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Affiliation(s)
- Marianna Marchini
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy
| | - Massimo Baroncini
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy.,Present address: Dipartimento di Scienze e, Tecnologie Agro-alimentari, Università di Bologna, viale Fanin 50, 40127, Bologna, Italy
| | - Giacomo Bergamini
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy.,Interuniversity Center for the Chemical Conversion of Solar Energy, Bologna Unit, Università di Bologna, Italy
| | - Paola Ceroni
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy.,Interuniversity Center for the Chemical Conversion of Solar Energy, Bologna Unit, Università di Bologna, Italy
| | - Mila D'Angelantonio
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, via Gobetti 101, 40129, Bologna, Italy
| | - Paola Franchi
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy
| | - Marco Lucarini
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy
| | - Fabrizia Negri
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy
| | - Tomasz Szreder
- Institute of Nuclear Chemistry and Technology, 16 Dorodna Str., 03-195, Warsaw, Poland
| | - Margherita Venturi
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via Selmi 2, 40126, Bologna, Italy.,Interuniversity Center for the Chemical Conversion of Solar Energy, Bologna Unit, Università di Bologna, Italy
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13
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Manbeck GF, Fujita E, Concepcion JJ. Proton-Coupled Electron Transfer in a Strongly Coupled Photosystem II-Inspired Chromophore–Imidazole–Phenol Complex: Stepwise Oxidation and Concerted Reduction. J Am Chem Soc 2016; 138:11536-49. [DOI: 10.1021/jacs.6b03506] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gerald F. Manbeck
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973-5000, United States
| | - Etsuko Fujita
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973-5000, United States
| | - Javier J. Concepcion
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973-5000, United States
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14
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Čížková M, Pospíšil L, Klepetářová B, Koval D, Teplý F. Linquats: Synthesis, Characterization, and Properties of Linear Extended Diquats. Chemistry 2016; 22:12154-9. [PMID: 27405657 DOI: 10.1002/chem.201600819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Indexed: 11/08/2022]
Abstract
We report an innovative synthetic route to linear extended diquats (linquats). Our approach is short and efficient and features a highly modular reaction sequence based on two-fold quaternization followed by the key intramolecular [2+2+2] alkyne cycloaddition. The physico-chemical properties of four new linquats were characterized by spectroscopic methods, X-ray crystallography, and electrochemistry complemented by information obtained from DFT calculations. Electron deficient N-heteroaromatic cations with linear extended diquat motif with high electron affinities have been recently recognized as attractive n-type semiconductors for chemical and biological sensing. Their advantageous redox properties such as very fast reversible electron transfers make the title compounds interesting for applications.
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Affiliation(s)
- Martina Čížková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10, Prague 6, Czech Republic
| | - Lubomír Pospíšil
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10, Prague 6, Czech Republic.,J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23, Prague 8, Czech Republic
| | - Blanka Klepetářová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10, Prague 6, Czech Republic
| | - Dušan Koval
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10, Prague 6, Czech Republic
| | - Filip Teplý
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10, Prague 6, Czech Republic.
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15
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Zhou C, Tian J, Wang JL, Zhang DW, Zhao X, Liu Y, Li ZT. A three-dimensional cross-linking supramolecular polymer stabilized by the cooperative dimerization of the viologen radical cation. Polym Chem 2014. [DOI: 10.1039/c3py01006f] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Moriya KTM, Tanaka T. Reduction ofn-C5H11N3Catalyzed by [Mo2Fe6S8(OMe)3(SC6H4-p-n-C8H17)6]3-in an Aqueous Micellar Solution. Isr J Chem 2013. [DOI: 10.1002/ijch.198800009] [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]
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17
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Salnikov DS, Silaghi-Dumitrescu R, Makarov SV, van Eldik R, Boss GR. Cobalamin reduction by dithionite. Evidence for the formation of a six-coordinate cobalamin(II) complex. Dalton Trans 2011; 40:9831-4. [PMID: 21879074 DOI: 10.1039/c1dt10219b] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Evidence for the formation of a unique, six-coordinate cobalamin(II) complex with the anion-radical SO(2)(-) during the reduction of aquacobalamin(III) by sodium dithionite, was obtained from spectrophotometric and EPR measurements. The pK(a) value of the weakly coordinated dimethylbenzimidazole group was found to be 4.8 ± 0.1 at 25 °C.
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18
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Sato K, Nakahodo T, Fujihara H. Redox-active π-conjugated polymer nanotubes with viologen for encapsulation and release of fluorescent dye in the nanospace. Chem Commun (Camb) 2011; 47:10067-9. [DOI: 10.1039/c1cc13853g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Henrich JD, Zhang H, Dutta PK, Kohler B. Ultrafast Electron Transfer Dynamics in Ruthenium Polypyridyl Complexes with a π-Conjugated Ligand. J Phys Chem B 2010; 114:14679-88. [DOI: 10.1021/jp102776r] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joseph D. Henrich
- Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210, and Department of Chemistry and Biochemistry, Montana State University, P.O. Box 173400, Bozeman, Montana 59717
| | - Haoyu Zhang
- Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210, and Department of Chemistry and Biochemistry, Montana State University, P.O. Box 173400, Bozeman, Montana 59717
| | - Prabir K. Dutta
- Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210, and Department of Chemistry and Biochemistry, Montana State University, P.O. Box 173400, Bozeman, Montana 59717
| | - Bern Kohler
- Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210, and Department of Chemistry and Biochemistry, Montana State University, P.O. Box 173400, Bozeman, Montana 59717
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20
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Vachon J, Bernardinelli G, Lacour J. Resolution of the First Nonracemic Diquats. Chemistry 2010; 16:2797-805. [DOI: 10.1002/chem.200902562] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Xiao Y, Zahariou G, Sanakis Y, Liu P. IspG enzyme activity in the deoxyxylulose phosphate pathway: roles of the iron-sulfur cluster. Biochemistry 2009; 48:10483-5. [PMID: 19821611 DOI: 10.1021/bi901519q] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
IspG is a [4Fe-4S] cluster-containing protein, and the [4Fe-4S](+) species is proposed to be the catalytically relevant species. However, attempts reported in the literature failed to detect the [4Fe-4S](+) species. In this study, using a potent reduction system, we have successfully detected the [4Fe-4S](+) species with X-band EPR spectroscopy. In addition, we have improved the Escherichia coli IspG activity to 550 nmol min(-1) mg(-1), which is approximately 20-fold greater than that of the NADPH-Fpr-FldA system in the literature.
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Affiliation(s)
- Youli Xiao
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
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22
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Günther H, Simon H. Artificial Electron Carriers for Preparative Biocatalytic Redox Reactions Forming Reversibly Carbon Hydrogen Bonds with Enzymes Present in Strict or Facultative Anaerobes. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.3109/10242429508998147] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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23
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Xiao Y, Chu L, Sanakis Y, Liu P. Revisiting the IspH Catalytic System in the Deoxyxylulose Phosphate Pathway: Achieving High Activity. J Am Chem Soc 2009; 131:9931-3. [DOI: 10.1021/ja903778d] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Youli Xiao
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, and Institute of Materials Science, NCSR “Demokritos”, 15310 Ag. Paraskevi, Attiki, Greece
| | - Lisa Chu
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, and Institute of Materials Science, NCSR “Demokritos”, 15310 Ag. Paraskevi, Attiki, Greece
| | - Yiannis Sanakis
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, and Institute of Materials Science, NCSR “Demokritos”, 15310 Ag. Paraskevi, Attiki, Greece
| | - Pinghua Liu
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, and Institute of Materials Science, NCSR “Demokritos”, 15310 Ag. Paraskevi, Attiki, Greece
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24
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Hallenbeck PC, George GN, Prince RC, Thorneley RNF. Characterization of a modified nitrogenase Fe protein from Klebsiella pneumoniae in which the 4Fe4S cluster has been replaced by a 4Fe4Se cluster. J Biol Inorg Chem 2009; 14:673-82. [PMID: 19234722 DOI: 10.1007/s00775-009-0480-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Accepted: 02/06/2009] [Indexed: 11/25/2022]
Abstract
The Azotobacter vinelandii nifS gene product has been used with selenocysteine to reconstitute Klebsiella pneumoniae nitrogenase Fe protein. Chemical analysis and extended X-ray absorption fine structure (EXAFS) spectroscopy show that the 4Fe4S cluster present in the native protein is replaced by a 4Fe4Se cluster. As well, EXAFS spectroscopy shows that the bond lengths to the cysteine thiolate ligands shrink by 0.05 A (from 2.28 to 2.23 A) upon reduction, whereas the Fe-Fe distance is essentially unchanged. Thus, the core of the 4Fe4Se cluster remains essentially static on reduction, whilst the external cysteine thiolate ligands are pulled in towards the cluster. Compared with native (S)-Fe protein, the (Se)-Fe protein has a 20-fold increased rate of MgATP-induced Fe chelation, a sixfold decreased specific activity for acetylene reduction, a fivefold decreased rate of MgATP-dependent electron transfer from (Se)-Fe protein to MoFe protein, and a fourfold increase in the ATP to 2e (-) ratio. The high ATP to 2e (-) ratio and decreased specific activity are consistent with a lower rate of dissociation of oxidized (Se)-Fe protein from reduced MoFe protein. Thus, the relatively small adjustments in the Fe protein structure necessary to accommodate the 4Fe4Se cluster are transmitted both to adjacent residues that dock at the surface of the MoFe protein and to the ATP hydrolysis sites located approximately 19 A away.
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Affiliation(s)
- Patrick Clark Hallenbeck
- Département de Microbiologie et Immunologie, Université de Montréal, Succursale Centre-ville, Montreal, QC, Canada.
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25
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Yamashita S, Katsumura Y, Lin M, Muroya Y, Miyazaki T, Murakami T, Meesungnoen J, Jay-Gerin JP. Water Radiolysis with Heavy Ions of Energies up to 28 GeV. 3. Measurement ofG(MV·+) in Deaerated Methyl Viologen Solutions Containing Various Concentrations of Sodium Formate and Monte Carlo Simulation. Radiat Res 2008; 170:521-33. [DOI: 10.1667/rr1203.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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26
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Takashima H, Tara C, Namikawa S, Kato T, Araki Y, Ito O, Tsukahara K. Photoinduced Intramolecular Electron-Transfer Reactions of Reconstituted Met- and Zinc-Myoglobins Appending Acridine and Methylacridinium Ion as DNA-Binders. J Phys Chem B 2006; 110:26413-23. [PMID: 17181301 DOI: 10.1021/jp0655571] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three types of reconstituted met- and zinc-myoglobin (metMb and ZnMb) dyads, ZnMbAc(4)Me+, ZnMbAc(6)Me+, and metMbAc(6) have been prepared by incorporating chemically modified metalloporphyrin cofactor appending an acridine (Ac) or a methylacridinium ion ([AcMe]+) into apo-Mb. In the bimolecular system between ZnMb and [AcMe]+, the photoexcited triplet state of ZnMb, 3(ZnMb)*, was successfully quenched by [AcMe]+ to form the radical pair of ZnMb cation (ZnMb*+) and reduced methylacridine ([AcMe]*), followed by a thermal back ET reaction. The rate constants for the intermolecular quenching ET (kq) and the back ET reaction (kb) at 25 degrees C were successfully obtained as kq = (8.8 +/- 0.4) x 10(7) M(-1) s(-1) and kb = (1.2 +/- 0.1) x 10(8) M(-1) s(-1), respectively. On the other hand, in case of the intramolecular photoinduced ET reactions of ZnMbAc(4)Me+ and ZnMbAc(6)Me+ dyads, the first-order quenching rate constants (kET) of 3(ZnMb)* by [AcMe]+ moiety were determined to be kET = 2.6 x 10(3) and 2.5 x 10(3) s(-1), respectively. When such ET occurs along the alkyl spacer via through-bond mechanism at the surface of Mb, the obtained kET is reasonable to provide decay constant of beta (1.0-1.3 A(-1)). Upon photoirradiation of [AcMe]+ moiety, kinetic studies also presented the intramolecular quenching reactions from the excited singlet state, 1([AcMe]+)*, whose likely process is the photoinduced energy-transfer reaction. For metMbAc(6) dyad, steady-state fluorescence was almost quenched, while the signal around 440 nm gradually appeared in the presence of various concentrations of DNA. Our study implies that synthetic manipulation at the Mb surface, by using an artificial DNA-binder coupled with photoinduced reaction, may provide valuable information to construct new Mb-DNA complex and sensitive fluorescent for DNA.
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Affiliation(s)
- Hiroshi Takashima
- Department of Chemistry, Faculty of Science, Nara Women's University, Nara, 630-8506 Japan.
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27
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Yasui S, Itoh K, Ohno A, Tokitoh N. Effect of structural change in viologen acceptors on the rate of single electron transfer from tributylphosphine. Org Biomol Chem 2006; 4:2928-31. [PMID: 16855741 DOI: 10.1039/b605362a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The "flexible" 3 and "rigid" cyclic viologens 4, diquarternary salts of 2,2'-bipyridine and 1,10-phenanthroline, respectively, were treated with tributylphosphine (1) in acetonitrile containing a large amount of methanol under an argon atmosphere. A single electron transfer (SET) easily occurred from the latter to the former, the SET to 4 being 10(5)-10(6) times faster than the SET to 3. The reorganization energy lambda for the latter SET is thought to be larger than that for the former SET, because 3 undergoes a structural change upon the one-electron reduction to its radical cation, whereas the one-electron reduction of 4 takes place without a structural change. Taking into account the difference in lambda, and also taking into account the bond formation energy brought about by the follow-up reaction of the phosphine radical cation 1*(+) with methanol, the observed kinetics were well interpreted in terms of the Marcus theory.
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Affiliation(s)
- Shinro Yasui
- Tezukayama University, Gakuen-Minami, Nara, Japan.
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28
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Kudrik EV, Makarov SV, Zahl A, van Eldik R. Kinetics and Mechanism of the Iron Phthalocyanine Catalyzed Reduction of Nitrite by Dithionite and Sulfoxylate in Aqueous Solution. Inorg Chem 2005; 44:6470-5. [PMID: 16124829 DOI: 10.1021/ic0505955] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reactions of sodium nitrite with sodium dithionite and sulfoxylate ion were studied in the presence of iron(III) tetrasulfophthalocyanine, Fe(III)(TSPc)3-, in aqueous alkaline solution. Kinetic parameters for the different reaction steps in the catalytic reduction by dithionite were determined. The final product of the reaction was found to be nitrous oxide. Contrary to this, the product of the catalytic reduction of nitrite by sulfoxylate was found to be ammonia. The striking difference in the reaction products is accounted for in terms of different structures of the intermediate complexes formed during the reduction by dithionite and sulfoxylate, in which nitrite is suggested to coordinate to the iron complex via nitrogen and oxygen, respectively. Sulfoxylate is shown to be a convenient reductant for the synthesis of the highly reduced iron phthalocyanine species Fe(I)(TSPc*)6- in aqueous solution. The kinetics of the reduction of Fe(I)(TSPc)5- to Fe(I)(TSPc*)6-, as well as the oxidation of the latter species by nitrite, was studied in detail.
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Affiliation(s)
- Evgeny V Kudrik
- Institute for Inorganic Chemistry, University of Erlangen-Nürnberg, Egerlandstrasse 1, 91058 Erlangen, Germany.
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29
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Yasui S, Itoh K, Ohno A, Tokitoh N. Dramatic effect of N-substituents in viologens on single electron transfer from tributylphosphine. Org Biomol Chem 2005; 3:4188-92. [PMID: 16294246 DOI: 10.1039/b512678a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A single electron transfer (SET) takes place from tributylphosphine (1a) to 1-alkyl-1'-methylviologens in acetonitrile containing a large amount of methanol under an argon atmosphere. In contrast, no SET takes place from 1a to viologens whose alkyl groups on the nitrogens are larger than the methyl group under the same conditions, 1a instead nucleophilically attacking the viologen to form a covalent adduct. This dramatic substituent effect is discussed in terms of SET occurring within a tight encounter complex formed between the phosphine and the viologen.
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Affiliation(s)
- Shinro Yasui
- Tezukayama University, Gakuen-Minami, Nara, 631-8585, Japan.
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30
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Kovelenov YA, Blake AJ, George MW, Matousek P, Mel'nikov MY, Parker AW, Sun XZ, Towrie M, Weinstein JA. Pt(ii) mono-carbonyl complexes of a cyclometallating 2-(2′-thienyl)-(pyridinato-C,3N′) ligand: nature and dynamics of the lowest excited state of the chloro- and thiolato-complexes. Dalton Trans 2005:2092-7. [PMID: 15957048 DOI: 10.1039/b502375k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of a cyclometallated Pt(II) thiolate carbonyl complex Pt(thpy)(CO)(mts), (thpy = 2-(2'-thienyl)-pyridinate, mts = methylthiosalicylate) is reported. A combination of emission and time-resolved infrared (TRIR) techniques revealed for both Pt(thpy)(CO)(mts) and its chloride analogue Pt(thpy)(CO)Cl the predominant intra 2-(2'-thienyl)-pyridinate 3pi pi* character of the lowest electronic excited state. The unusually short lifetime (780 ps) of the intraligand 3pi pi* lowest excited state of Pt(thpy)(CO)(mts) indicates that this electronic state is influenced by another close-lying excited state, probably charge-transfer in origin.
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Affiliation(s)
- Yurii A Kovelenov
- School of Chemistry, University of Nottingham, Nottingham, UK NG7 2RD
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31
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Das TN, Ghanty TK, Pal H. Reactions of Methyl Viologen Dication (MV2+) with H Atoms in Aqueous Solution: Mechanism Derived from Pulse Radiolysis Measurements and ab Initio MO Calculations. J Phys Chem A 2003. [DOI: 10.1021/jp022614r] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tomi Nath Das
- Radiation Chemistry & Chemical Dynamics Division, Bhabha Atomic Research Centre (B.A.R.C.), Trombay, Mumbai 400 085, India
| | - Tapan K. Ghanty
- Radiation Chemistry & Chemical Dynamics Division, Bhabha Atomic Research Centre (B.A.R.C.), Trombay, Mumbai 400 085, India
| | - Haridas Pal
- Radiation Chemistry & Chemical Dynamics Division, Bhabha Atomic Research Centre (B.A.R.C.), Trombay, Mumbai 400 085, India
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32
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Tsukahara K, Ueda R. Stereoselective Photoinduced Electron-Transfer Reaction between Zinc Myoglobin and New Chiral Quinolinium Ions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2003. [DOI: 10.1246/bcsj.76.561] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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33
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MORI YUKIE, HOSHINO MIKIO, HAYASHI HISAHARU. Magnetic field effects on electron transfer reactions involving sextet-spin (S= 5/2) intermediates generated on photoexcitation of a Cr(III)-porphyrin complex. Mol Phys 2002. [DOI: 10.1080/00268970110109727] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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34
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Miller C, Folkes LK, Mottley C, Wardman P, Mason RP. Revisiting the interaction of the radical anion metabolite of nitrofurantoin with glutathione. Arch Biochem Biophys 2002; 397:113-8. [PMID: 11747317 DOI: 10.1006/abbi.2001.2670] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There have been several conflicting reports as to the scavenging nature of glutathione toward the nitro radical anion of the drug nitrofurantoin. We produced the radical anion enzymatically using the xanthine oxidase/hypoxanthine system at pH 7.4 and pH 9.0 in the presence of various levels of glutathione from 10 to 100 mM and monitored any changes in the radical concentration via electron spin resonance spectroscopy. Independent of glutathione concentration, there was no decrease in the steady-state concentration of the radical. In fact, there was an average 30% increase in the concentration of the radical anion, which suggests enhanced enzyme activity in the presence of glutathione (GSH). These results, together with observations of the effects of glutathione on the stability of the radical anion generated by radiolysis or dithionite, rule out any detectable reaction between the nitrofurantoin radical anion and GSH under physiologically relevant conditions.
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Affiliation(s)
- Catherine Miller
- Department of Chemistry, John Carroll University, Cleveland, Ohio 44118, USA.
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Yasui S, Itoh K, Ohno A, Tokitoh N. Kinetic Deuterium Isotope Effect in Single-Electron Transfer Occurring from Tributylphosphine to Viologens. CHEM LETT 2001. [DOI: 10.1246/cl.2001.1056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Dobbing AM, Borman CD, Twitchett MB, Leese DN, Salmon GA, Sykes AG. Mechanistic Implications of a Linear Free-Energy Correlation of Rate Constants for the Reduction of Active- and Met-R2 Forms of E. coli Ribonucleotide Reductase with Eight Organic Radicals. J Am Chem Soc 2000. [DOI: 10.1021/ja993412k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. Mark Dobbing
- Contribution from the Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK, and The University of Leeds, Cookridge Radiation Research Centre, Leeds, LS16 6PB, UK
| | - Christopher D. Borman
- Contribution from the Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK, and The University of Leeds, Cookridge Radiation Research Centre, Leeds, LS16 6PB, UK
| | - Mark B. Twitchett
- Contribution from the Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK, and The University of Leeds, Cookridge Radiation Research Centre, Leeds, LS16 6PB, UK
| | - David N. Leese
- Contribution from the Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK, and The University of Leeds, Cookridge Radiation Research Centre, Leeds, LS16 6PB, UK
| | - G. Arthur Salmon
- Contribution from the Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK, and The University of Leeds, Cookridge Radiation Research Centre, Leeds, LS16 6PB, UK
| | - A. Geoffrey Sykes
- Contribution from the Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK, and The University of Leeds, Cookridge Radiation Research Centre, Leeds, LS16 6PB, UK
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Rogers JE, Weiss SJ, Kelly LA. Photoprocesses of Naphthalene Imide and Diimide Derivatives in Aqueous Solutions of DNA. J Am Chem Soc 2000. [DOI: 10.1021/ja992332d] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joy E. Rogers
- Contribution from the Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250
| | - Sharon J. Weiss
- Contribution from the Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250
| | - Lisa A. Kelly
- Contribution from the Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250
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Borman CD, Dobbing AM, Salmon GA, Sykes AG. Rate Constants and Free-Energy Plot for the Reduction of Horse-Heart Cytochrome c(III) by Eight Organic Radicals. J Phys Chem B 1999. [DOI: 10.1021/jp984520g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christopher D. Borman
- Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, U.K., and Cookridge Radiation Research Centre, The University of Leeds, Cookridge Hospital, Leeds LS16 6QB, U.K
| | - A. Mark Dobbing
- Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, U.K., and Cookridge Radiation Research Centre, The University of Leeds, Cookridge Hospital, Leeds LS16 6QB, U.K
| | - G. Arthur Salmon
- Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, U.K., and Cookridge Radiation Research Centre, The University of Leeds, Cookridge Hospital, Leeds LS16 6QB, U.K
| | - A. Geoffrey Sykes
- Department of Chemistry, The University of Newcastle, Newcastle upon Tyne, NE1 7RU, U.K., and Cookridge Radiation Research Centre, The University of Leeds, Cookridge Hospital, Leeds LS16 6QB, U.K
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Andersen NH, Hervás M, Navarro J, De la Rosa MA, Ulstrup J. Photosensitized electron transfer reactions of cytochrome c4 from Pseudomonas stutzeri with flavins and methyl viologen. Inorganica Chim Acta 1998. [DOI: 10.1016/s0020-1693(97)05874-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Cambie RC, Milbank JBJ, Rutledge PS. REDUCTIVE CLAISEN REARRANGEMENTS OF ALLYLOXYANTHRAQUINONES. A REVIEW. ORG PREP PROCED INT 1997. [DOI: 10.1080/00304949709355216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Liu Y, Seefeldt LC, Parker VD. Entropies of redox reactions between proteins and mediators: the temperature dependence of reversible electrode potentials in aqueous buffers. Anal Biochem 1997; 250:196-202. [PMID: 9245439 DOI: 10.1006/abio.1997.2222] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The temperature dependencies of the reversible electrode potentials for a number of charge transfer reactions of redox mediators were used to evaluate the corresponding charge transfer entropies in Tris-HCl (pH 8) buffer. The redox mediator thermodynamic data, along with reaction enthalpy data for mediator redox protein electron transfer, were used to evaluate the charge transfer entropy for the cytochrome c redox couple [(cytc)ox/(cytc)red] in Tris-HCl (pH 8) buffer and were found to be equal to -16 cal/degrees K mol. Reversible electrode potentials at 298 degrees K for the redox mediator half-reactions were observed to vary from -528 to +657 mV (vs NHE). Charge transfer entropies were observed to depend upon the structure of the redox mediators and to vary from -13.8 to -29.7 cal/degrees K mol for a closely related series of organic dications (viologens) and a value of -43.6 cal/degrees K mol was observed for the [Fe(CN)6]3-/[Fe(CN)6]4- couple under the same conditions. A procedure for determining charge transfer entropies of protein redox couples which cannot be studied by direct electrochemical methods is outlined. The factors contributing to the magnitude of the charge transfer entropies are discussed.
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Affiliation(s)
- Y Liu
- Department of Chemistry and Biochemistry, Utah State University, Logan 84322-0300, USA
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Bockman TM, Hubig SM, Kochi JK. Direct Observation of Ultrafast Decarboxylation of Acyloxy Radicals via Photoinduced Electron Transfer in Carboxylate Ion Pairs. J Org Chem 1997; 62:2210-2221. [PMID: 11671531 DOI: 10.1021/jo9617833] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Charge-transfer (CT) photoactivation of the electron donor-acceptor salts of methylviologen (MV(2+)) with carboxylate donors (RCO(2)(-)) including benzilates [Ar(2)C(OH)CO(2)(-)] and arylacetates (ArCH(2)CO(2)(-)) leads to transient [MV(*)(+), RCO(2)(*)] radical pairs. Femtosecond time-resolved spectroscopy reveals that the photogenerated acyloxy radicals (RCO(2)(*)) rapidly lose carbon dioxide by C-CO(2) bond cleavage, in competition with back-electron transfer to restore the original ion pair, [MV(2+), RCO(2)(-)]. The decarboxylation rate constants for ArCH(2)CO(2)(*) lie in the range (1-2) x 10(9) s(-)(1), in agreement with previous reports. In striking contrast, the C-CO(2) bond scission in Ar(2)C(OH)CO(2)(*) occurs within a few picoseconds (k(CC) = (2-8) x 10(11) s(-)(1)). The rate constants for decarboxylation of these donors approach those of barrier-free unimolecular reactions. Thus, real-time monitoring of the decarboxylation of benziloxy radicals represents the means for the direct observation of the transition state for C-C bond scission.
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Affiliation(s)
- T. Michael Bockman
- Department of Chemistry, University of Houston, Houston, Texas 77204-5641
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Nieckarz GF, Weakley TJR, Miller WK, Miller BE, Lyon DK, Tyler DR. Generation of 19-Electron Adducts in Aqueous Solution Using the Water-Soluble (HOCH(2))(2)PCH(2)CH(2)P(CH(2)OH)(2) Ligand. Inorg Chem 1996; 35:1721-1724. [PMID: 11666399 DOI: 10.1021/ic951071f] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gregory F. Nieckarz
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403-1253, Bend Research, 64550 Research Road, Bend, Oregon 97701-8599, and Department of Chemistry, Wheaton College, Wheaton, Illinois 60187
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Teresa Bes M, de Lacey AL, Fernandez VM, Gomez-Moreno C. Electron transfer between viologen derivatives and the flavoprotein ferredoxin-NADP+ reductase. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/0302-4598(95)01817-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Crystal structure and solid-state fluorescence of an oxomolybdenum(V)-benzylviologen electron donor-acceptor salt. Inorganica Chim Acta 1994. [DOI: 10.1016/0020-1693(94)04067-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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1,4-Bis(1,2,6-triphenyl-4-pyridyl)benzene as a novel hydrophobic electron relay for dihydrogen evolution in photocatalytic systems based on lipid vesicles. J Photochem Photobiol A Chem 1994. [DOI: 10.1016/1010-6030(94)03812-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Tsukahara K, Nishikawa Y, Kimura C, Sawai N, Sakurai T. Kinetics and Mechanisms of Photoinduced Electron-Transfer Reaction of Magnesium Myoglobin. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1994. [DOI: 10.1246/bcsj.67.2093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Tsukahara K, Asami S, Okada M, Sakurai T. Kinetics and Mechanisms of Photoinduced Electron-Transfer Reaction of Zinc Myoglobin. Intracomplex vs. Intermolecular Quenching Controlled by Conformational Change Associated with Charge and Steric Bulk of Quenchers. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1994. [DOI: 10.1246/bcsj.67.421] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Nanasawa M, Kaneko M, Kamogawa H. Photochromism of Viologen Hexacyanoferrate(II) Complexes via Intramolecular Electron Transfer. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1993. [DOI: 10.1246/bcsj.66.1764] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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