1
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Wei C, Zhang Y, Qu Y, Hua W, Jia Z, Lu J, Xie G, Xiao J, Hu H, Yang Y, Liu JQ, Bai J, Xue G. Dual Channel H 2O 2 Photosynthesis in Pure Water over S-Scheme Heterojunction Cs 3PMo 12/CC Boosted by Proton and Electron Reservoirs. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2401485. [PMID: 38712455 DOI: 10.1002/smll.202401485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 04/24/2024] [Indexed: 05/08/2024]
Abstract
Dual channel photo-driven H2O2 production in pure water on small-scale on-site setups is a promising strategy to provide low-concentrated H2O2 whenever needed. This process suffers, however, strongly from the fast recombination of photo-generated charge carriers and the sluggish oxidation process. Here, insoluble Keggin-type cesium phosphomolybdate Cs3PMo12O40 (abbreviated to Cs3PMo12) is introduced to carbonized cellulose (CC) to construct S-scheme heterojunction Cs3PMo12/CC. Dual channel H2O2 photosynthesis from both H2O oxidation and O2 reduction in pure water has been thus achieved with the production rate of 20.1 mmol L-1 gcat. -1 h-1, apparent quantum yield (AQY) of 2.1% and solar-to-chemical conversion (SCC) efficiency of 0.050%. H2O2 accumulative concentration reaches 4.9 mmol L-1. This high photocatalytic activity is guaranteed by unique features of Cs3PMo12/CC, namely, S-scheme heterojunction, electron reservoir, and proton reservoir. The former two enhance the separation of photo-generated charge carriers, while the latter speeds up the torpid oxidation process. In situ experiments reveal that H2O2 is formed via successive single-electron transfer in both channels. In real practice, exposing the reaction system under natural sunlight outdoors successfully results in 0.24 mmol L-1 H2O2. This work provides a key practical strategy for designing photocatalysts in modulating redox half-reactions in photosynthesis.
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Affiliation(s)
- Chong Wei
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
| | - Yu Zhang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
| | - Yunteng Qu
- State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & PhotonTechnology, Northwest University, Xi'an, 710069, China
- Shaanxi Key Laboratory for Carbon Neutral Technology, Northwest University, Xi'an, 710127, China
| | - Wenbo Hua
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
| | - Zixian Jia
- SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co., Ltd, Dalian, 116045, China
| | - Jiangbo Lu
- School of Physics & Information Technology, Shaanxi Normal University, Xi'an, Shaanxi, 710062, China
| | - Gang Xie
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
- Shaanxi Key Laboratory for Carbon Neutral Technology, Northwest University, Xi'an, 710127, China
| | - Jianming Xiao
- Department College of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Huaiming Hu
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
| | - Ying Yang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
- Shaanxi Key Laboratory for Carbon Neutral Technology, Northwest University, Xi'an, 710127, China
| | - Ji-Quan Liu
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
- Shaanxi Key Laboratory for Carbon Neutral Technology, Northwest University, Xi'an, 710127, China
| | - Jinbo Bai
- CentraleSupélec, ENS Paris-Saclay, CNRS, LMPS-Laboratoire de Mécanique Paris-Saclay, Université Paris-Saclay, 8-10 rue Joliot-Curie, Gif-sur-Yvette, 91190, France
| | - Ganglin Xue
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Ave., Xi'an, 710127, China
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2
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Evans R, Krahn N, Weiss J, Vincent KA, Söll D, Armstrong FA. Replacing a Cysteine Ligand by Selenocysteine in a [NiFe]-Hydrogenase Unlocks Hydrogen Production Activity and Addresses the Role of Concerted Proton-Coupled Electron Transfer in Electrocatalytic Reversibility. J Am Chem Soc 2024; 146:16971-16976. [PMID: 38747098 PMCID: PMC11212049 DOI: 10.1021/jacs.4c03489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 06/27/2024]
Abstract
Hydrogenases catalyze hydrogen/proton interconversion that is normally electrochemically reversible (having minimal overpotential requirement), a special property otherwise almost exclusive to platinum metals. The mechanism of [NiFe]-hydrogenases includes a long-range proton-coupled electron-transfer process involving a specific Ni-coordinated cysteine and the carboxylate of a nearby glutamate. A variant in which this cysteine has been exchanged for selenocysteine displays two distinct changes in electrocatalytic properties, as determined by protein film voltammetry. First, proton reduction, even in the presence of H2 (a strong product inhibitor), is greatly enhanced relative to H2 oxidation: this result parallels a characteristic of natural [NiFeSe]-hydrogenases which are superior H2 production catalysts. Second, an inflection (an S-shaped "twist" in the trace) appears around the formal potential, the small overpotentials introduced in each direction (oxidation and reduction) signaling a departure from electrocatalytic reversibility. Concerted proton-electron transfer offers a lower energy pathway compared to stepwise transfers. Given the much lower proton affinity of Se compared to that of S, the inflection provides compelling evidence that concerted proton-electron transfer is important in determining why [NiFe]-hydrogenases are reversible electrocatalysts.
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Affiliation(s)
- Rhiannon
M. Evans
- Department
of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Natalie Krahn
- Department
of Biochemistry and Molecular Biology, University
of Georgia, Athens, Georgia 30602, United
States
| | - Joshua Weiss
- Department
of Biochemistry and Molecular Biology, University
of Georgia, Athens, Georgia 30602, United
States
| | - Kylie A. Vincent
- Department
of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Dieter Söll
- Department
of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06511, United States
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Fraser A. Armstrong
- Department
of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
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3
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Ould Mohamed L, Abtouche S, Ghoualem Z, Assfeld X. Unraveling redox pathways of the disulfide bond in dimethyl disulfide: Ab initio modeling. J Mol Model 2024; 30:180. [PMID: 38780881 DOI: 10.1007/s00894-024-05963-8] [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: 03/14/2024] [Accepted: 05/03/2024] [Indexed: 05/25/2024]
Abstract
CONTEXT In cellular environments, the reduction of disulfide bonds is pivotal for protein folding and synthesis. However, the intricate enzymatic mechanisms governing this process remain poorly understood. This study addresses this gap by investigating a disulfide bridge reduction reaction, serving as a model for comprehending electron and proton transfer in biological systems. Six potential mechanisms for reducing the dimethyl disulfide (DMDS) bridge through electron and proton capture were explored. Thermodynamic and kinetic analyses elucidated the sequence of proton and electron addition. MD-PMM, a method that combines molecular dynamics simulations and quantum-chemical calculations, was employed to compute the redox potential of the mechanism. This research provides valuable insights into the mechanisms and redox potentials involved in disulfide bridge reduction within proteins, offering an understanding of phenomena that are challenging to explore experimentally. METHODS All calculations used the Gaussian 09 software package at the MP2/6-311 + g(d,p) theory level. Visualization of the molecular orbitals and electron densities was conducted using Gaussview6. Molecular dynamics simulations were performed using GROMACS with the CHARMM36 force field. The PyMM program (Python Program for QM/MM Simulations Based on the Perturbed Matrix Method) is used to apply the Perturbed Matrix Method to MD simulations.
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Affiliation(s)
- Lina Ould Mohamed
- Laboratoire de Physico Chimie Théorique Et Chimie Informatique, LPCTCI, Faculté de Chimie, USTHB, 16111, Algiers, Algeria
| | - Soraya Abtouche
- Laboratoire de Physico Chimie Théorique Et Chimie Informatique, LPCTCI, Faculté de Chimie, USTHB, 16111, Algiers, Algeria.
| | - Zeyneb Ghoualem
- Laboratoire de Physico Chimie Théorique Et Chimie Informatique, LPCTCI, Faculté de Chimie, USTHB, 16111, Algiers, Algeria
| | - Xavier Assfeld
- Physique et Chimie Théoriques, UMR 7019, Faculté des Sciences et Technologies, Université de Lorraine, BP 70239, 54506, Vandoeuvre Lès Nancy Cedex, France
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4
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Xue Y, Sexton TM, Yang J, Tschumper GS. Systematic analysis of electronic barrier heights and widths for concerted proton transfer in cyclic hydrogen bonded clusters: (HF) n, (HCl) n and (H 2O) n where n = 3, 4, 5. Phys Chem Chem Phys 2024; 26:12483-12494. [PMID: 38619858 DOI: 10.1039/d4cp00422a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
The MP2 and CCSD(T) methods are paired with correlation consistent basis sets as large as aug-cc-pVQZ to optimize the structures of the cyclic minima for (HF)n, (HCl)n and (H2O)n where n = 3-5, as well as the corresponding transition states (TSs) for concerted proton transfer (CPT). MP2 and CCSD(T) harmonic vibrational frequencies confirm the nature of each minimum and TS. Both conventional and explicitly correlated CCSD(T) computations are employed to assess the electronic dissociation energies and barrier heights for CPT near the complete basis (CBS) limit for all 9 clusters. Results for (HF)n are consistent with prior studies identifying Cnh and Dnh point group symmetry for the minima and TSs, respectively. Our computations also confirm that CPT proceeds through Cs TS structures for the C1 minima of (H2O)3 and (H2O)5, whereas the process goes through a TS with D2d symmetry for the S4 global minimum of (H2O)4. This work corroborates earlier findings that the minima for (HCl)3, (HCl)4 and (HCl)5 have C3h, S4 and C1 point group symmetry, respectively, and that the Cnh structures are not minima for n = 4 and 5. Moreover, our computations show the TSs for CPT in (HCl)3, (HCl)4 and (HCl)5 have D3h, D2d, and C2 point group symmetry, respectively. At the CCSD(T) CBS limit, (HF)4 and (HF)5 have the smallest electronic barrier heights for CPT (≈15 kcal mol-1 for both), followed by the HF trimer (≈21 kcal mol-1). The barriers are appreciably higher for the other clusters (around 27 kcal mol-1 for (H2O)4 and (HCl)3; roughly 30 kcal mol-1 for (H2O)3, (H2O)5 and (HCl)4; up to 38 kcal mol-1 for (HCl)5). At the CBS limit, MP2 significantly underestimates the CCSD(T) barrier heights (e.g., by ca. 2, 4 and 7 kcal mol-1 for the pentamers of HF, H2O and HCl, respectively), whereas CCSD overestimates these barriers by roughly the same magnitude. Scaling the barrier heights and dissociation energies by the number of fragments in the cluster reveals strong linear relationships between the two quantities and with the magnitudes of the imaginary vibrational frequency for the TSs.
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Affiliation(s)
- Yuan Xue
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677-1848, USA.
| | - Thomas More Sexton
- School of Arts and Sciences, Chemistry University of Mary, Bismark, ND 58504, USA.
| | - Johnny Yang
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677-1848, USA.
| | - Gregory S Tschumper
- Department of Chemistry and Biochemistry, University of Mississippi, University, MS 38677-1848, USA.
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5
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Tikhonov AN. The cytochrome b 6f complex: plastoquinol oxidation and regulation of electron transport in chloroplasts. PHOTOSYNTHESIS RESEARCH 2024; 159:203-227. [PMID: 37369875 DOI: 10.1007/s11120-023-01034-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023]
Abstract
In oxygenic photosynthetic systems, the cytochrome b6f (Cytb6f) complex (plastoquinol:plastocyanin oxidoreductase) is a heart of the hub that provides connectivity between photosystems (PS) II and I. In this review, the structure and function of the Cytb6f complex are briefly outlined, being focused on the mechanisms of a bifurcated (two-electron) oxidation of plastoquinol (PQH2). In plant chloroplasts, under a wide range of experimental conditions (pH and temperature), a diffusion of PQH2 from PSII to the Cytb6f does not limit the intersystem electron transport. The overall rate of PQH2 turnover is determined mainly by the first step of the bifurcated oxidation of PQH2 at the catalytic site Qo, i.e., the reaction of electron transfer from PQH2 to the Fe2S2 cluster of the high-potential Rieske iron-sulfur protein (ISP). This point has been supported by the quantum chemical analysis of PQH2 oxidation within the framework of a model system including the Fe2S2 cluster of the ISP and surrounding amino acids, the low-potential heme b6L, Glu78 and 2,3,5-trimethylbenzoquinol (the tail-less analog of PQH2). Other structure-function relationships and mechanisms of electron transport regulation of oxygenic photosynthesis associated with the Cytb6f complex are briefly outlined: pH-dependent control of the intersystem electron transport and the regulatory balance between the operation of linear and cyclic electron transfer chains.
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Affiliation(s)
- Alexander N Tikhonov
- Department of Biophysics, Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russian Federation, 119991.
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6
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Hamadouche S, Merouani H, May AA, Ouddai N, Alam M, Micoli L, Erto A, Benguerba Y. Theoretical Exploration of Enhanced Antioxidant Activity in Copper Complexes of Tetrahydroxystilbenes: Insights into Mechanisms and Molecular Interactions. ACS OMEGA 2024; 9:9076-9089. [PMID: 38434904 PMCID: PMC10906065 DOI: 10.1021/acsomega.3c07885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 03/05/2024]
Abstract
A theoretical investigation was conducted using DFT/PW91/TZP/DMSO calculations on a complete set of exhaustive lists of 18 compounds resulting from the complexation of trans-2,4,3',5'-tetrahydroxystilbene (T-OXY) and cis-2,4,1',3'-tetrahydroxystilbene (C-OXY) with copper metal cations (Cu+ and Cu2+). The ligand-binding sites are the critical points of Quantum Theory of Atoms in Molecules (QTAIM) analysis on neutral and deprotonated ligands. Various mechanisms, including hydrogen atom transfer (HAT), sequential proton loss electron transfer (SPLET), single electron transfer followed by proton transfer (SET-PT), and bond dissociation energy (BDE(E0)) calculations, were employed to quantify the antioxidant activity. The BDE(E0) mechanism emerged as the most suitable approach for such analyses to evaluate the departure of hydrogen atoms since the results show the HAT mechanism is the most likely occurring. Particularly intriguing were the anionic Cu+ complexes with ligands adopting trans configurations and deprotonated conformations, displaying superior antioxidant activity compared to their counterparts. Remarkably, a single ligand within the Cu+ complex exhibited exceptional antioxidant prowess, yielding a BDE(E0) value of 91.47 kcal/mol. Furthermore, a complex involving two deprotonated ligands demonstrated antioxidant activity of 31.12 kcal/mol, signifying its potential as a potent antiradical agent, surpassing T-OXY by a factor of 3.91 and even surpassing the antioxidant efficiency of Vitamin C.
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Affiliation(s)
- Salima Hamadouche
- Laboratoire
de Chimie des Matériaux et des Vivants: Activité &
Réactivité (LCMVAR), Université
Batna 1, 5000 Batna, Algeria
| | - Hafida Merouani
- Laboratoire
de Chimie des Matériaux et des Vivants: Activité &
Réactivité (LCMVAR), Université
Batna 1, 5000 Batna, Algeria
- Département
de Socle Commun, Faculté de Technologie, Université Ben Boulaid Batna 2, 05078 Batna, Algeria
| | - Abd Alghani May
- Département
de Chimie, Faculté des Sciences Exacte, Université Frères Mentouri 1, 25017 Constantine, Algeria
| | - Nadia Ouddai
- Laboratoire
de Chimie des Matériaux et des Vivants: Activité &
Réactivité (LCMVAR), Université
Batna 1, 5000 Batna, Algeria
| | - Manawwer Alam
- Department
of Chemistry, College of Science, King Saud
University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Luca Micoli
- Dipartimento
di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università di Napoli Federico II, P.le Tecchio, 80, 80125 Napoli, Italy
| | - Alessandro Erto
- Dipartimento
di Ingegneria Industriale, Università
di Napoli Federico II, P.le Tecchio, 80, 80125 Napoli, Italy
| | - Yacine Benguerba
- Laboratoire
de Biopharmacie and Pharmacotechnie (LBPt), Department of Process
Engineering, Faculty of Technology, Ferhat
Abbas Setif 1 University, 19000 Setif, Algeria
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7
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Fatima S, Farzeen I, Ashraf A, Aslam B, Ijaz MU, Hayat S, Sarfraz MH, Zafar S, Zafar N, Unuofin JO, Lebelo SL, Muzammil S. A Comprehensive Review on Pharmacological Activities of Pachypodol: A Bioactive Compound of an Aromatic Medicinal Plant Pogostemon Cablin Benth. Molecules 2023; 28:molecules28083469. [PMID: 37110702 PMCID: PMC10141922 DOI: 10.3390/molecules28083469] [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: 03/09/2023] [Revised: 03/29/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
As is well known, plant products have been increasingly utilized in the pharmaceutical industry in recent years. By combining conventional techniques and modern methodology, the future of phytomedicines appears promising. Pogostemon Cablin (patchouli) is an important herb used frequently in the fragrance industries and has various therapeutic benefits. Traditional medicine has long used the essential oil of patchouli (P. cablin) as a flavoring agent recognized by the FDA. This is a gold mine for battling pathogens in China and India. In recent years, this plant has seen a significant surge in use, and approximately 90% of the world's patchouli oil is produced by Indonesia. In traditional therapies, it is used for the treatment of colds, fever, vomiting, headaches, and stomachaches. Patchouli oil is used in curing many diseases and in aromatherapy to treat depression and stress, soothe nerves, regulate appetite, and enhance sexual attraction. More than 140 substances, including alcohols, terpenoids, flavonoids, organic acids, phytosterols, lignins, aldehydes, alkaloids, and glycosides, have been identified in P. cablin. Pachypodol (C18H16O7) is an important bioactive compound found in P. cablin. Pachypodol (C18H16O7) and many other biologically essential chemicals have been separated from the leaves of P. cablin and many other medicinally significant plants using repeated column chromatography on silica gel. Pachypodol's bioactive potential has been shown by a variety of assays and methodologies. It has been found to have a number of biological activities, including anti-inflammatory, antioxidant, anti-mutagenic, antimicrobial, antidepressant, anticancer, antiemetic, antiviral, and cytotoxic ones. The current study, which is based on the currently available scientific literature, intends to close the knowledge gap regarding the pharmacological effects of patchouli essential oil and pachypodol, a key bioactive molecule found in this plant.
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Affiliation(s)
- Sehrish Fatima
- Department of Zoology, Government College University, Faisalabad 38000, Pakistan
| | - Iqra Farzeen
- Department of Zoology, Government College University, Faisalabad 38000, Pakistan
| | - Asma Ashraf
- Department of Zoology, Government College University, Faisalabad 38000, Pakistan
| | - Bilal Aslam
- Institute of Microbiology, Government College University, Faisalabad 38000, Pakistan
| | - Muhammad Umar Ijaz
- Department of Zoology, Wildlife and Fisheries, University of Agriculture, Faisalabad 38040, Pakistan
| | - Sumreen Hayat
- Institute of Microbiology, Government College University, Faisalabad 38000, Pakistan
| | | | - Saima Zafar
- Department of Zoology, Government College University, Faisalabad 38000, Pakistan
| | - Nimrah Zafar
- Department of Zoology, Government College University, Faisalabad 38000, Pakistan
| | - Jeremiah Oshiomame Unuofin
- Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, Private Bag X06, Florida 1710, South Africa
| | - Sogolo Lucky Lebelo
- Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, Private Bag X06, Florida 1710, South Africa
| | - Saima Muzammil
- Institute of Microbiology, Government College University, Faisalabad 38000, Pakistan
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8
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Mena LD, Baumgartner MT. Chalcogen Atoms as Electron Donors in Proton-Coupled Electron Transfer Reactions. J Am Chem Soc 2022; 144:15922-15927. [PMID: 36018719 DOI: 10.1021/jacs.2c05602] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Proton-coupled electron transfer (PCET) reactions are crucial for the optimal functioning of a broad scope of chemical and biological processes. In this report, we present an unprecedented type of concerted PCET (cPCET), in which a chalcogen atom acts as the electron donor. The nature of this mechanism is key for understanding the reactivity of different radical-trapping antioxidants having heavy chalcogens (S, Se, or Te) in their structures. Moreover, this chalcogen-assisted cPCET is likely to be occurring in multiple systems of biological interest.
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Affiliation(s)
- Leandro D Mena
- QUIAMM-INBIOTEC-Departamento de Química, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata B7600, Argentina
| | - María T Baumgartner
- INFIQC, Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000, Argentina
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9
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Nandy A, Adamji H, Kastner DW, Vennelakanti V, Nazemi A, Liu M, Kulik HJ. Using Computational Chemistry To Reveal Nature’s Blueprints for Single-Site Catalysis of C–H Activation. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Aditya Nandy
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Husain Adamji
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - David W. Kastner
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Vyshnavi Vennelakanti
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Azadeh Nazemi
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mingjie Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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10
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Borrego E, Tiessler-Sala L, Lázaro JJ, Caballero A, Pérez PJ, Lledós A. Direct Benzene Hydroxylation with Dioxygen Induced by Copper Complexes: Uncovering the Active Species by DFT Calculations. Organometallics 2022; 41:1892-1904. [PMID: 35936655 PMCID: PMC9344391 DOI: 10.1021/acs.organomet.2c00202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The direct oxidation of benzene into phenol using molecular
oxygen
at very mild temperatures can be promoted in the presence of the copper
complex TpBr3Cu(NCMe) in the homogeneous phase in the presence
of ascorbic acid as the source of protons and electrons. The stoichiometric
nature, relative to copper, of this transformation prompted a thorough
DFT study in order to understand the reaction pathway. As a result,
the dinuclear species TpBr3CuII(μ-O•)(μ-OH)CuIITpBr3 is proposed
as the relevant structure which is responsible for activating the
arene C–H bond leading to phenol formation.
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Affiliation(s)
- Elena Borrego
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Química Sostenible and Departamento de Química, Universidad de Huelva, Huelva 21007, Spain
| | - Laura Tiessler-Sala
- Departament de Química, Universitat Autònoma de Barcelona, Cerdanyola del
Vallès, Barcelona 08193, Spain
| | - Jesus J. Lázaro
- Cepsa Research Center, Compañía Española de Petróleos S.A., Alcalá de Henares, Madrid 28850, Spain
| | - Ana Caballero
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Química Sostenible and Departamento de Química, Universidad de Huelva, Huelva 21007, Spain
| | - Pedro J. Pérez
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Química Sostenible and Departamento de Química, Universidad de Huelva, Huelva 21007, Spain
| | - Agustí Lledós
- Departament de Química, Universitat Autònoma de Barcelona, Cerdanyola del
Vallès, Barcelona 08193, Spain
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11
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Salaverri N, Carli B, Díaz-Tendero S, Marzo L, Alemán J. Enantioselective Addition of Remote Alkyl Radicals to Double Bonds by Photocatalytic Proton-Coupled Electron Transfer (PCET) Deconstruction of Unstrained Cycloalkanols. Org Lett 2022; 24:3123-3127. [PMID: 35362991 PMCID: PMC9087350 DOI: 10.1021/acs.orglett.2c00662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Herein, we report
the enantioselective addition of remote alkyl
radicals, generated from the ring opening of unstrained cycloalkanols
by a proton-coupled electron transfer (PCET) process, to 2-acyl imidazoles
previously coordinated to a rhodium-based chiral Lewis acid. High
yields and enantioselectivites up to 99% are achieved in 1 h. Mechanistic
investigations support the formation of the remote alkyl radical by
a PCET process, and theoretical studies explain the observed stereochemistry
in the addition step.
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Affiliation(s)
- Noelia Salaverri
- Departamento de Química Orgánica (Módulo 1), Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain
| | - Benedetta Carli
- Departamento de Química Orgánica (Módulo 1), Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain
| | - Sergio Díaz-Tendero
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049, Madrid, Spain.,Condensed Matter Physics Center (IFIMAC), Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain.,Departamento de Química (Módulo 13), Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain
| | - Leyre Marzo
- Departamento de Química Orgánica (Módulo 1), Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain
| | - José Alemán
- Departamento de Química Orgánica (Módulo 1), Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain.,Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049, Madrid, Spain
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12
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Voltammetric kinetic discrimination of two sequential proton-coupled electron transfers in serotonin oxidation: Electrochemical interrogation of a serotonin intermediate. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.139973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Murray PD, Cox JH, Chiappini ND, Roos CB, McLoughlin EA, Hejna BG, Nguyen ST, Ripberger HH, Ganley JM, Tsui E, Shin NY, Koronkiewicz B, Qiu G, Knowles RR. Photochemical and Electrochemical Applications of Proton-Coupled Electron Transfer in Organic Synthesis. Chem Rev 2022; 122:2017-2291. [PMID: 34813277 PMCID: PMC8796287 DOI: 10.1021/acs.chemrev.1c00374] [Citation(s) in RCA: 172] [Impact Index Per Article: 86.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Indexed: 12/16/2022]
Abstract
We present here a review of the photochemical and electrochemical applications of multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms in which both an electron and a proton are exchanged together, often in a concerted elementary step. As such, MS-PCET can function as a non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from a wide variety of common organic functional groups. We present an introduction to MS-PCET and a practitioner's guide to reaction design, with an emphasis on the unique energetic and selectivity features that are characteristic of this reaction class. We then present chapters on oxidative N-H, O-H, S-H, and C-H bond homolysis methods, for the generation of the corresponding neutral radical species. Then, chapters for reductive PCET activations involving carbonyl, imine, other X═Y π-systems, and heteroarenes, where neutral ketyl, α-amino, and heteroarene-derived radicals can be generated. Finally, we present chapters on the applications of MS-PCET in asymmetric catalysis and in materials and device applications. Within each chapter, we subdivide by the functional group undergoing homolysis, and thereafter by the type of transformation being promoted. Methods published prior to the end of December 2020 are presented.
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Affiliation(s)
- Philip
R. D. Murray
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - James H. Cox
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Nicholas D. Chiappini
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Casey B. Roos
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | | | - Benjamin G. Hejna
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Suong T. Nguyen
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Hunter H. Ripberger
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Jacob M. Ganley
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Elaine Tsui
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Nick Y. Shin
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Brian Koronkiewicz
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Guanqi Qiu
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Robert R. Knowles
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
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14
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Gotico P, Herrero C, Protti S, Quaranta A, Sheth S, Fallahpour R, Farran R, Halime Z, Sircoglou M, Aukauloo A, Leibl W. Proton-controlled Action of an Imidazole as Electron Relay in a Photoredox Triad. Photochem Photobiol Sci 2022; 21:247-259. [PMID: 34988933 DOI: 10.1007/s43630-021-00163-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 12/18/2021] [Indexed: 11/24/2022]
Abstract
Electron relays play a crucial role for efficient light-induced activation by a photo-redox moiety of catalysts for multi-electronic transformations. Their insertion between the two units reduces detrimental energy transfer quenching while establishing at the same time unidirectional electron flow. This rectifying function allows charge accumulation necessary for catalysis. Mapping these events in photophysical studies is an important step towards the development of efficient molecular photocatalysts. Three modular complexes comprised of a Ru-chromophore, an imidazole electron relay function, and a terpyridine unit as coordination site for a metal ion were synthesized and the light-induced electron transfer events studied by laser flash photolysis. In all cases, formation of an imidazole radical by internal electron transfer to the oxidized chromophore was observed. The effect of added base evidenced that the reaction sequence depends strongly on the possibility for deprotonation of the imidazole function in a proton-coupled electron transfer process. In the complex with MnII present as a proxy for a catalytic site, a strongly accelerated decay of the imidazole radical together with a decreased rate of back electron transfer from the external electron acceptor to the oxidized complex was observed. This transient formation of an imidazolyl radical is clear evidence for the function of the imidazole group as an electron relay. The implication of the imidazole proton and the external base for the kinetics and energetics of the electron trafficking is discussed.
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Affiliation(s)
- Philipp Gotico
- Institut de Biologie Intégrative de La Cellule (I2BC), Université Paris Saclay, CEA, CNRS, 91191, Gif-sur-Yvette, France
| | - Christian Herrero
- Institut de Chimie Moléculaire Et Des Matériaux d'Orsay (ICMMO), Université Paris Saclay, 91405, Orsay, France
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia, 27100, Pavia, Italy
| | - Annamaria Quaranta
- Institut de Biologie Intégrative de La Cellule (I2BC), Université Paris Saclay, CEA, CNRS, 91191, Gif-sur-Yvette, France
| | - Sujitraj Sheth
- Institut de Biologie Intégrative de La Cellule (I2BC), Université Paris Saclay, CEA, CNRS, 91191, Gif-sur-Yvette, France
| | - Reza Fallahpour
- Department of Chemistry, University of Zürich UZH, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Rajaa Farran
- Institut de Biologie Intégrative de La Cellule (I2BC), Université Paris Saclay, CEA, CNRS, 91191, Gif-sur-Yvette, France.,Lebanese International University, Mazraa, Beirut, 146404, Lebanon
| | - Zakaria Halime
- Institut de Chimie Moléculaire Et Des Matériaux d'Orsay (ICMMO), Université Paris Saclay, 91405, Orsay, France
| | - Marie Sircoglou
- Institut de Chimie Moléculaire Et Des Matériaux d'Orsay (ICMMO), Université Paris Saclay, 91405, Orsay, France
| | - Ally Aukauloo
- Institut de Chimie Moléculaire Et Des Matériaux d'Orsay (ICMMO), Université Paris Saclay, 91405, Orsay, France
| | - Winfried Leibl
- Institut de Biologie Intégrative de La Cellule (I2BC), Université Paris Saclay, CEA, CNRS, 91191, Gif-sur-Yvette, France.
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15
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Rand AW, Chen M, Montgomery J. Investigations into mechanism and origin of regioselectivity in the metallaphotoredox-catalyzed α-arylation of N-alkylbenzamides. Chem Sci 2022; 13:10566-10573. [PMID: 36277638 PMCID: PMC9473500 DOI: 10.1039/d2sc01962k] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/19/2022] [Indexed: 11/25/2022] Open
Abstract
A mechanistic study on the α-arylation of N-alkylbenzamides catalyzed by a dual nickel/photoredox system using aryl bromides is reported herein. This study elucidates the origins of site-selectivity of the transformation, which is controlled by the generation of a hydrogen atom transfer (HAT) agent by a photocatalyst and bromide ions in solution. Tetrabutylammonium bromide was identified as a crucial additive and source of a potent HAT agent, which led to increases in yields and a lowering of the stoichiometries of the aryl bromide coupling partner. NMR titration experiments and Stern–Volmer quenching studies provide evidence for complexation to and oxidation of bromide by the photocatalyst, while elementary steps involving deprotonation of the N-alkylbenzamide or 1,5-HAT were ruled out through mechanistic probes and kinetic isotope effect analysis. This study serves as a valuable tool to better understand the α-arylation of N-alkylbenzamides, and has broader implications in halide-mediated C–H functionalization reactions. A mechanistic study of the α-arylation of N-alkylbenzamides catalyzed by a dual nickel/photoredox system using aryl bromides elucidates the origins of site-selectivity of the transformation and identifies the hydrogen atom transfer agent.![]()
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Affiliation(s)
- Alexander W. Rand
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109-1055, USA
| | - Mo Chen
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109-1055, USA
| | - John Montgomery
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109-1055, USA
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16
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Moolayadukkam S, Vishwanathan S, Jun B, Lee SU, Matte HSSR. Unveiling the effect of the crystalline phases of iron oxyhydroxide for highly sensitive and selective detection of dopamine. Dalton Trans 2021; 50:13497-13504. [PMID: 34494039 DOI: 10.1039/d1dt01672e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Electrocatalysis is key to the development of several important energy and biosensing applications. In this regard, the crystalline phase-dependent electrocatalytic activity of materials has been extensively studied for reactions such as hydrogen evolution, oxygen reduction, etc. But such comprehensive studies for evaluating the phase-dependence of electrochemical biosensing have not been undertaken. Herein, three crystalline phases (α-, β-, and γ-) of iron oxyhydroxide (FeOOH) have been synthesized and characterized by spectroscopic and microscopy techniques. Electrochemical studies revealed their high sensitivity and selectivity towards dopamine (DA) detection. Amongst the three electrocatalysts, β-FeOOH shows the highest sensitivity (337.15 μA mM-1 cm-2) and the lowest detection limit (0.56 μM). The enhanced electrocatalytic activity of β-FeOOH, as compared to that of α- and γ-FeOOH, was attributed to its higher active site percentage and facile electrode kinetics. Furthermore, theoretical studies probed into the DA-FeOOH interactions by evaluating the charge transfer characteristics and hydrogen adsorption energies of the three phases to support the experimental findings.
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Affiliation(s)
- Sreejesh Moolayadukkam
- Energy Materials Laboratory, Centre for Nano and Soft Matter Sciences, Bangalore, 562162, India.
| | - Savithri Vishwanathan
- Energy Materials Laboratory, Centre for Nano and Soft Matter Sciences, Bangalore, 562162, India.
| | - Byeongsun Jun
- Department of Bionano Technology, Hanyang University, Ansan, 15588, Republic of Korea
| | - Sang Uck Lee
- Department of Bionano Technology, Hanyang University, Ansan, 15588, Republic of Korea.,Department of Applied Chemistry, Hanyang University, Ansan, 15588, Republic of Korea
| | - H S S Ramakrishna Matte
- Energy Materials Laboratory, Centre for Nano and Soft Matter Sciences, Bangalore, 562162, India.
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17
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Wang W, Tse ECM. Proton Removal Kinetics That Govern the Hydrogen Peroxide Oxidation Activity of Heterogeneous Bioinorganic Platforms. Inorg Chem 2021; 60:6900-6910. [PMID: 33621073 DOI: 10.1021/acs.inorgchem.0c03743] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Precise regulation of proton-coupled electron-transfer (PCET) rates holds the key to simultaneously optimizing the turnover frequency and product selectivity of redox reactions that are central to the realization of renewable energy schemes in a sustainable future. In this work, a self-assembled monolayer (SAM) of a Ru complex electrografted onto a glassy carbon (GC) electrode was prepared as a heterogeneous electrocatalytic interface to facilitate the hydrogen peroxide (H2O2) oxidation half-cell reaction of a direct hydrogen peroxide/hydrogen peroxide fuel cell. A functional lipid membrane embedded with catalytic amounts of proton carriers was appended on top of the Ru SAM to construct a hybrid bilayer membrane (HBM) platform that can modulate the thermodynamics and kinetics of proton- and electron-transfer steps independently. The performances of the as-prepared Ru SAMs and HBMs toward H2O2 oxidation were investigated using electrochemical means, kinetic isotope effect (KIE) studies, and Tafel analyses. Proton carriers featuring borate, phosphate, and nitrile headgroups were found to dictate the transmembrane proton removal rate, thereby controlling the H2O2 oxidation activity. The first significance of this work was the expansion of HBM platforms to GC substrates to overcome the limited redox potential window on gold thiol systems, thereby enabling electrochemical investigations of anodic reactions at the SAM-lipid interface. The second highlight of this work was demonstrating for the first time that deprotonation kinetics can be taken advantage of to enhance the electrocatalytic oxidation performance of a metal complex anchored at the SAM-lipid interface of a HBM platform. When the knowledge gaps regarding how PCET steps govern redox pathways are closed, the advances achieved using our unique bioinorganic platform are envisioned to accelerate the understanding and optimization of electrocatalytic processes involving proton- and electron- transfer steps that are fundamental to the development of high-performance energy devices.
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Affiliation(s)
- Wanying Wang
- Department of Chemistry, HKU-CAS Joint Laboratory on New Materials, University of Hong Kong (HKU), Pok Fu Lam, Hong Kong Special Administrative Region, China
| | - Edmund C M Tse
- Department of Chemistry, HKU-CAS Joint Laboratory on New Materials, University of Hong Kong (HKU), Pok Fu Lam, Hong Kong Special Administrative Region, China.,HKU Zhejiang Institute of Research and Innovation, Zhejiang 311305, China
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18
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Hamadouche S, Ounissi A, Baira K, Ouddai N, Balsamo M, Erto A, Benguerba Y. Theoretical evaluation of the antioxidant activity of some stilbenes using the Density Functional Theory. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2020.129496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Gorantla KR, Mallik BS. Mechanism and Dynamics of Formation of Bisoxo Intermediates and O-O Bond in the Catalytic Water Oxidation Process. J Phys Chem A 2021; 125:279-290. [PMID: 33370125 DOI: 10.1021/acs.jpca.0c09943] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This work elucidates the reactivity of water molecules toward the tridentate nitrogen-containing iron complex in the water oxidation process. Here, we consider the FeV-bisoxo complex {[FeV(Me3tacn)(OH2)(═O)2]+} to be responsible for the oxygen-oxygen bond formation. This O-O bond formation happens through the addition of water as a nucleophile. The transition state was determined by the synchronous transit-guided quasi-Newton method using reactants and products and verified by intrinsic reaction coordinates (IRCs). From the IRC calculations, we observe that the FeV═O moiety is attacked by water and assisted by the H-bonded interaction with the oxygen atom of the bisoxo complex. The hydrogen atom is transferred to the oxygen atom of the bisoxo complex through the transition state, and subsequently, the hydroxide is transferred to another oxygen of the bisoxo complex, resulting in the formation of the oxygen-oxygen bond. This work also explains the effect of explicit water molecules on the oxygen-oxygen bond formation. Our results also show how the formation of superoxide plays an essential role in O2 evolution. We used the potential energy scan method to compute the transition state in the oxygen evolution step. In the present work, we study the effect of chlorine on the formation of the oxygen-oxygen bond formation. In this study, the changes in the oxidation state, spin density, and spin multiplicity of the complexes are investigated for each successive step. Apart from these static theoretical calculations, we also studied the oxygen-oxygen bond formation through first-principles molecular dynamics with the aid of the well-tempered metadynamics sampling technique. From the observation of the free energy surfaces from metadynamics simulations, it is evident that the hydroxide transfer has a lesser free energetic reaction as compared to the proton transfer. This complete mechanistic study may give an idea to design a suitable water oxidation catalyst.
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Affiliation(s)
- Koteswara Rao Gorantla
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285 Telangana, India
| | - Bhabani S Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285 Telangana, India
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20
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Berg N, Bergwinkl S, Nuernberger P, Horinek D, Gschwind RM. Extended Hydrogen Bond Networks for Effective Proton-Coupled Electron Transfer (PCET) Reactions: The Unexpected Role of Thiophenol and Its Acidic Channel in Photocatalytic Hydroamidations. J Am Chem Soc 2021; 143:724-735. [DOI: 10.1021/jacs.0c08673] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Nele Berg
- Institute of Organic Chemistry, University of Regensburg, D-93053 Regensburg, Germany
| | - Sebastian Bergwinkl
- Institute of Physical and Theoretical Chemistry, University of Regensburg, D-93053 Regensburg, Germany
| | - Patrick Nuernberger
- Institute of Physical and Theoretical Chemistry, University of Regensburg, D-93053 Regensburg, Germany
| | - Dominik Horinek
- Institute of Physical and Theoretical Chemistry, University of Regensburg, D-93053 Regensburg, Germany
| | - Ruth M. Gschwind
- Institute of Organic Chemistry, University of Regensburg, D-93053 Regensburg, Germany
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21
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Zhou Z, Kong X, Liu T. Applications of Proton-Coupled Electron Transfer in Organic Synthesis. CHINESE J ORG CHEM 2021. [DOI: 10.6023/cjoc202106001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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22
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Zeng T, Gautam RP, Barile CJ, Li Y, Tse ECM. Nitrile-Facilitated Proton Transfer for Enhanced Oxygen Reduction by Hybrid Electrocatalysts. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03506] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Tian Zeng
- Department of Chemistry, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, University of Hong Kong, Hong Kong SAR 999077, China
| | - Rajendra P. Gautam
- Department of Chemistry, University of Nevada, Reno, Nevada 89557, United States
| | | | - Ying Li
- Department of Chemistry, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, University of Hong Kong, Hong Kong SAR 999077, China
- HKU Shenzhen Institute of Research and Innovation, Shenzhen 518057, China
| | - Edmund C. M. Tse
- Department of Chemistry, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, University of Hong Kong, Hong Kong SAR 999077, China
- HKU Zhejiang Institute of Research and Innovation, Zhejiang 311305, China
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23
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Nolte TM, Nauser T, Gubler L, Hendriks AJ, Peijnenburg WJGM. Thermochemical unification of molecular descriptors to predict radical hydrogen abstraction with low computational cost. Phys Chem Chem Phys 2020; 22:23215-23225. [PMID: 33029596 DOI: 10.1039/d0cp03750h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chemistry describes transformation of matter with reaction equations and corresponding rate constants. However, accurate rate constants are not always easy to get. Here we focus on radical oxidation reactions. Analysis of over 500 published rate constants of hydroxyl radicals led us to hypothesize that a modified linear free-energy relationship (LFER) could be used to predict rate constants speedily, reliably and accurately. LFERs correlate the Gibbs activation-energy with the Gibbs energy of reaction. We calculated the latter as the sum of one-electron transfer and, if appropriate, proton transfer. We parametrized specific transition state effects to orbital delocalizability and the polarity of the reactant. The calculation time for 500 reactions is less than 8 hours on a standard desktop-PC. Rate constants were also calculated for hydrogen and methyl radicals; these controls show that the predictions are applicable to a broader set of oxidizing radicals. An accuracy of 30-40% (standard deviation) with reference to reported experimental values was found suitable for the screening of complex chemical systems for possibly relevant reactions. In particular, potentially relevant reactions can be singled out and scrutinized in detail when prioritizing chemicals for environmental risk assessment.
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Affiliation(s)
- Tom M Nolte
- Eidgenössische Technische Hochschule (ETH) Zurich, Laboratory of Inorganic Chemistry, Vladimir-Prelog-Weg 1, 8093 Zurich, Switzerland.
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24
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Botella-Martínez C, Lucas-González R, Pérez-Álvarez JA, Fernández-López J, Viuda-Martos M. Assessment of chemical composition and antioxidant properties of defatted flours obtained from several edible insects. FOOD SCI TECHNOL INT 2020; 27:383-391. [PMID: 32962449 DOI: 10.1177/1082013220958854] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The aims of this study were determined the chemical composition and the antioxidant properties of defatted flours obtained from several commercially available edible insects such as Acheta dosmesticus, Tenebrio molitor, Zophobas morio, and Rhynchophorus ferrugineus to establish their utilization as ingredient in the development of new food products. The proximate composition of flour was determined using AOAC methods while for antioxidant capacity, four different methodologies were employed (DPPH, ABTS, FIC, and FRAP). The total phenolic content and the tannin content were also determined. All flours analyzed had a high protein content with values ranging between 64.17 and 72.55 g/100 g flour. With regard to the antioxidant activity, R. ferrugineus showed the highest values for DPPH, ABTS, and FRAP assays with values of 2.03, 4.93, and 8.46 mg Trolox equivalent/g flour, respectively. For FIC assay, A. dosmesticus and T. molitor had the highest values 0.47 and 0.48 mg EDTA equivalent/g flour. Defatted flours obtained from edible insects analyzed could have several applications as ingredients to the development new foods due to its good nutrient content and as a functional food for the prevention of oxidation.
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Affiliation(s)
- Carmen Botella-Martínez
- IPOA Research Group, Agro-Food Technology Department, Escuela Politécnica Superior de Orihuela, Miguel Hernández University, Alicante, Spain
| | - Raquel Lucas-González
- IPOA Research Group, Agro-Food Technology Department, Escuela Politécnica Superior de Orihuela, Miguel Hernández University, Alicante, Spain
| | - José A Pérez-Álvarez
- IPOA Research Group, Agro-Food Technology Department, Escuela Politécnica Superior de Orihuela, Miguel Hernández University, Alicante, Spain
| | - Juana Fernández-López
- IPOA Research Group, Agro-Food Technology Department, Escuela Politécnica Superior de Orihuela, Miguel Hernández University, Alicante, Spain
| | - Manuel Viuda-Martos
- IPOA Research Group, Agro-Food Technology Department, Escuela Politécnica Superior de Orihuela, Miguel Hernández University, Alicante, Spain
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25
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Computational mechanistic study on molecular catalysis of water oxidation by cyclam ligand-based iron complex. Theor Chem Acc 2020. [DOI: 10.1007/s00214-020-02664-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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26
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Forneris CC, Nguy AKL, Seyedsayamdost MR. Mapping and Exploiting the Promiscuity of OxyB toward the Biocatalytic Production of Vancomycin Aglycone Variants. ACS Catal 2020; 10:9287-9298. [PMID: 34422446 PMCID: PMC8378672 DOI: 10.1021/acscatal.0c01719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Vancomycin is one of the most important clinical antibiotics in the fight against infectious disease. Its biological activity relies on three aromatic cross-links, which create a cup-shaped topology and allow tight binding to nascent peptidoglycan chains. The cytochrome P450 enzymes OxyB, OxyA, and OxyC have been shown to introduce these synthetically challenging aromatic linkages. The ability to utilize the P450 enzymes in a chemo-enzymatic scheme to generate vancomycin derivatives is appealing but requires a thorough understanding of their reactivities and mechanisms. Herein, we systematically explore the scope of OxyB biocatalysis and report installation of diverse diaryl ether and biaryl cross-links with varying macrocycle sizes and compositions, when the enzyme is presented with modified vancomycin precursor peptides. The structures of the resulting products were determined using one-dimensional/two-dimensional nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry (HR-MS), tandem HR-MS, and isotopic labeling, as well as ultraviolet-visible light absorption and fluorescence emission spectroscopies. An exploration of the biological activities of these alternative OxyB products surprisingly revealed antifungal properties. Taking advantage of the promiscuity of OxyB, we chemo-enzymatically generated a vancomycin aglycone variant containing an expanded macrocycle. Mechanistic implications for OxyB and future directions for creating vancomycin analogue libraries are discussed.
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Affiliation(s)
- Clarissa C Forneris
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Andy K L Nguy
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Mohammad R Seyedsayamdost
- Department of Chemistry and Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
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27
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Raucci U, Chiariello MG, Coppola F, Perrella F, Savarese M, Ciofini I, Rega N. An electron density based analysis to establish the electronic adiabaticity of proton coupled electron transfer reactions. J Comput Chem 2020; 41:1835-1841. [PMID: 32500950 DOI: 10.1002/jcc.26224] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/22/2020] [Accepted: 04/24/2020] [Indexed: 11/10/2022]
Abstract
Electrons and protons are the main actors in play in proton coupled electron transfer (PCET) reactions, which are fundamental in many biological (i.e., photosynthesis and enzymatic reactions) and electrochemical processes. The mechanism, energetics and kinetics of PCET reactions are strongly controlled by the coupling between the transferred electrons and protons. Concerted PCET reactions are classified according to the electronical adiabaticity degree of the process. To discriminate among different mechanisms, we propose a new analysis based on the use of electron density based indexes. We choose, as test case, the 3-Methylphenoxyl/phenol system in two different conformations to show how the proposed analysis is a suitable tool to discriminate between the different degree of adiabaticity of PCET processes. The very low computational cost of this procedure is extremely promising to analyze and provide evidences of PCET mechanisms ruling the reactivity of many biological and catalytic systems.
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Affiliation(s)
- Umberto Raucci
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, Napoli, Italy
| | - Maria Gabriella Chiariello
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, Napoli, Italy
| | - Federico Coppola
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, Napoli, Italy
| | - Fulvio Perrella
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, Napoli, Italy
| | | | - Ilaria Ciofini
- Chimie ParisTech, PSL Research University, CNRS, Institute of Chemistry for Life and Health Sciences, Paris, France
| | - Nadia Rega
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di M.S.Angelo, Napoli, Italy.,CRIB Center for Advanced Biomaterials for Healthcare, Napoli, Italy
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28
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Phenol-acclimated activated sludge and Ralstonia eutropha in a microbial fuel Cell for removal of olive oil from mill wastewater. KOREAN J CHEM ENG 2020. [DOI: 10.1007/s11814-020-0538-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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29
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Tanwar L, Börgel J, Ritter T. Synthesis of Benzylic Alcohols by C-H Oxidation. J Am Chem Soc 2019; 141:17983-17988. [PMID: 31689095 PMCID: PMC6863597 DOI: 10.1021/jacs.9b09496] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Indexed: 01/29/2023]
Abstract
Selective methylene C-H oxidation for the synthesis of alcohols with a broad scope and functional group tolerance is challenging due to the high proclivity for further oxidation of alcohols to ketones. Here, we report the selective synthesis of benzylic alcohols employing bis(methanesulfonyl) peroxide as an oxidant. We attempt to provide a rationale for the selectivity for monooxygenation, which is distinct from previous work; a proton-coupled electron transfer mechanism (PCET) may account for the difference in reactivity. We envision that our method will be useful for applications in the discovery of drugs and agrochemicals.
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Affiliation(s)
| | | | - Tobias Ritter
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der
Ruhr, Germany
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30
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Physical and electrochemical characterization of a Cu-based oxygen reduction electrocatalyst inside and outside a lipid membrane with controlled proton transfer kinetics. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.134611] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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31
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Takashima T, Ishikawa K, Irie H. Induction of Concerted Proton-Coupled Electron Transfer during Oxygen Evolution on Hematite Using Lanthanum Oxide as a Solid Proton Acceptor. ACS Catal 2019. [DOI: 10.1021/acscatal.9b02936] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Toshihiro Takashima
- Clean Energy Research Center, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
- Special Doctoral Program for Green Energy Conversion Science and Technology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
| | - Koki Ishikawa
- Special Doctoral Program for Green Energy Conversion Science and Technology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
| | - Hiroshi Irie
- Clean Energy Research Center, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
- Special Doctoral Program for Green Energy Conversion Science and Technology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
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32
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Vaddypally S, Tomlinson W, O’Sullivan OT, Ding R, Van Vliet MM, Wayland BB, Hooper JP, Zdilla MJ. Activation of C–H, N–H, and O–H Bonds via Proton-Coupled Electron Transfer to a Mn(III) Complex of Redox-Noninnocent Octaazacyclotetradecadiene, a Catenated-Nitrogen Macrocyclic Ligand. J Am Chem Soc 2019; 141:5699-5709. [DOI: 10.1021/jacs.8b10250] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shivaiah Vaddypally
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Warren Tomlinson
- Department of Physics, Naval Postgraduate School, 833 Dyer Road, Monterey, California 93943, United States
| | - Owen T. O’Sullivan
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Ran Ding
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Megan M. Van Vliet
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Bradford B. Wayland
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Joseph P. Hooper
- Department of Physics, Naval Postgraduate School, 833 Dyer Road, Monterey, California 93943, United States
| | - Michael J. Zdilla
- Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
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33
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Jackson MN, Jung O, Lamotte HC, Surendranath Y. Donor-Dependent Promotion of Interfacial Proton-Coupled Electron Transfer in Aqueous Electrocatalysis. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00056] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Megan N. Jackson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Onyu Jung
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Hamish C. Lamotte
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Yogesh Surendranath
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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34
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Del Río MP, Abril P, López JA, Sodupe M, Lledós A, Ciriano MA, Tejel C. Activating a Peroxo Ligand for C-O Bond Formation. Angew Chem Int Ed Engl 2019; 58:3037-3041. [PMID: 30589172 DOI: 10.1002/anie.201808840] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/24/2018] [Indexed: 12/12/2022]
Abstract
Dioxygen activation for effective C-O bond formation in the coordination sphere of a metal is a long-standing challenge in chemistry for which the design of catalysts for oxygenations is slowed down by the complicated, and sometimes poorly understood, mechanistic panorama. In this context, olefin-peroxide complexes could be valuable models for the study of such reactions. Herein, we showcase the isolation of rare "Ir(cod)(peroxide)" complexes (cod=1,5-cyclooctadiene) from reactions with oxygen, and then the activation of the peroxide ligand for O-O bond cleavage and C-O bond formation by transfer of a hydrogen atom through proton transfer/electron transfer reactions to give 2-iradaoxetane complexes and water. 2,4,6-Trimethylphenol, 1,4-hydroquinone, and 1,4-cyclohexadiene were used as hydrogen atom donors. These reactions can be key steps in the oxy-functionalization of olefins with oxygen, and they constitute a novel mechanistic pathway for iridium, whose full reaction profile is supported by DFT calculations.
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Affiliation(s)
- M Pilar Del Río
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009-, Zaragoza, Spain
| | - Paula Abril
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009-, Zaragoza, Spain
| | - José A López
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009-, Zaragoza, Spain
| | - Mariona Sodupe
- Departament de Química, Universitat Autónoma de Barcelona, Cerdanyola del Vallès, 08193-, Barcelona, Spain
| | - Agustí Lledós
- Departament de Química, Universitat Autónoma de Barcelona, Cerdanyola del Vallès, 08193-, Barcelona, Spain
| | - Miguel A Ciriano
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009-, Zaragoza, Spain
| | - Cristina Tejel
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, 50009-, Zaragoza, Spain
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35
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Bhakta S, Nayek A, Roy B, Dey A. Induction of Enzyme-like Peroxidase Activity in an Iron Porphyrin Complex Using Second Sphere Interactions. Inorg Chem 2019; 58:2954-2964. [DOI: 10.1021/acs.inorgchem.8b02707] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Snehadri Bhakta
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata, India 700032
| | - Abhijit Nayek
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata, India 700032
| | - Bijan Roy
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata, India 700032
| | - Abhishek Dey
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata, India 700032
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36
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37
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Thammavongsy Z, Mercer IP, Yang JY. Promoting proton coupled electron transfer in redox catalysts through molecular design. Chem Commun (Camb) 2019; 55:10342-10358. [DOI: 10.1039/c9cc05139b] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mini-review on using the secondary coordination sphere to facilitate multi-electron, multi-proton catalysis.
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Affiliation(s)
| | - Ian P. Mercer
- Department of Chemistry
- University of California
- Irvine
- USA
| | - Jenny Y. Yang
- Department of Chemistry
- University of California
- Irvine
- USA
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38
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Chu J, Carroll TG, Wu G, Telser J, Dobrovetsky R, Ménard G. Probing Hydrogen Atom Transfer at a Phosphorus(V) Oxide Bond Using a "Bulky Hydrogen Atom" Surrogate: Analogies to PCET. J Am Chem Soc 2018; 140:15375-15383. [PMID: 30382703 DOI: 10.1021/jacs.8b09063] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Recent computational studies suggest that the phosphate support in the commercial vanadium phosphate oxide (VPO) catalyst may play a critical role in initiating butane C-H bond activation through a mechanism termed reduction-coupled oxo activation (ROA) similar to proton-coupled electron transfer (PCET); however, no experimental evidence exists to support this mechanism. Herein, we present molecular model compounds, (Ph2N)3V═N-P(O)Ar2 (Ar = C6F5 (2a), Ph (2b)), which are reactive to both weak H atom donors and a Me3Si• (a "bulky hydrogen atom" surrogate) donor, 1,4-bis(trimethylsilyl)pyrazine. While the former reaction led to product decomposition, the latter resulted in the isolation of the reduced, silylated complexes (Ph2N)3V-N═P(OSiMe3)Ar2 (3a/b). Detailed analyses of possible reaction pathways, involving the isolation and full characterization of potential stepwise square-scheme intermediates, as well as the determination of minimum experimentally and computationally derived thermochemical values, are described. We find that stepwise electron transfer (ET) + silylium transfer (ST) or concerted EST mechanisms are most likely. This study provides the first experimental evidence supporting a ROA mechanism and may inform future studies in homogeneous or heterogeneous C-H activation chemistry, as well as open up a possible new avenue for main group/transition metal cooperative redox reactivity.
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Affiliation(s)
- Jiaxiang Chu
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Timothy G Carroll
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Guang Wu
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Joshua Telser
- Department of Biological, Chemical, and Physical Sciences , Roosevelt University , Chicago , Illinois 60605 , United States
| | - Roman Dobrovetsky
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences , Tel Aviv University , Tel Aviv 69978 , Israel
| | - Gabriel Ménard
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
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39
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Kotani H, Kaida S, Ishizuka T, Mieda K, Sakaguchi M, Ogura T, Shiota Y, Yoshizawa K, Kojima T. Importance of the Reactant-State Potentials of Chromium(V)–Oxo Complexes to Determine the Reactivity in Hydrogen-Atom Transfer Reactions. Inorg Chem 2018; 57:13929-13936. [DOI: 10.1021/acs.inorgchem.8b02453] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Hiroaki Kotani
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Suzue Kaida
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Tomoya Ishizuka
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Kaoru Mieda
- Graduate School of Life Science, University of Hyogo, Kouto, Hyogo 678-1297, Japan
| | - Miyuki Sakaguchi
- Graduate School of Life Science, University of Hyogo, Kouto, Hyogo 678-1297, Japan
| | - Takashi Ogura
- Graduate School of Life Science, University of Hyogo, Kouto, Hyogo 678-1297, Japan
| | - Yoshihito Shiota
- Institute for Materials Chemistry and Engineering, Kyushu University, Motooka, Nishi-Ku, Fukuoka 819-0395, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Motooka, Nishi-Ku, Fukuoka 819-0395, Japan
- Elements Strategy Initiative for Catalysts & Batteries, Kyoto University, Nishi-ku, Kyoto 615-8520, Japan
| | - Takahiko Kojima
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
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40
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Darcy JW, Koronkiewicz B, Parada GA, Mayer JM. A Continuum of Proton-Coupled Electron Transfer Reactivity. Acc Chem Res 2018; 51:2391-2399. [PMID: 30234963 DOI: 10.1021/acs.accounts.8b00319] [Citation(s) in RCA: 173] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Proton-coupled electron transfer (PCET) covers a wide range of reactions involving the transfer(s) of electrons and protons. The best-known PCET reaction, hydrogen atom transfer (HAT), has been studied in detail for more than a century. HAT is generally described as the concerted transfer of a hydrogen atom (H• ≡ H+ + e-) from one group to another, Y + H-X → Y-H + X, but a strict definition of HAT has been difficult to establish. Distinctions are more challenging when the transfer of "H•" involves e- and H+ that transfer to/from spatially distinct sites or even completely separate reagents (multiple-site concerted proton-electron transfer, MS-CPET). MS-CPET reactivity is increasingly proposed in biological and synthetic contexts, and some reactions typically described as HAT more resemble MS-CPET. Despite that HAT and MS-CPET reactions "look different," we argue here that these reactions lie on a reactivity continuum, and that they are governed by many of the same key parameters. This Account walks the reader across this PCET reactivity continuum, using a series of studies to show the strong similarities of reactions that move protons and electrons in seemingly different ways. To prepare for our stroll, we describe the thermochemical and kinetic frameworks for HAT and MS-CPET. The driving force for a solution HAT reaction is most easily discussed as the difference in the bond dissociation free energies (BDFEs) of the reactants and products. BDFEs can be analyzed as sums of electron and proton transfer steps and can therefore be obtained from p Ka and E° values. Even though MS-CPET reactions do not make and break H-X bonds in the same way as HAT, the same thermochemical description can be used with the introduction of an effective BDFE (BDFEeff). The BDFEeff of a reductant/acid pair is the free energy of that pair to form H•, which can be obtained from p Ka and E° values in an analogous fashion to a standard BDFE. When the PCET thermochemistry is known, HAT and PCET rate constants can be understood and often predicted using linear free energy relationships (the Brønsted catalysis law) and Marcus theory type approaches. After this background, we walk the reader through a continuum of PCET reactivity. Our journey begins with a study of metal-mediated HAT from hydrocarbon substrates to a metal-oxo complex and travels to the MS-CPET end of the reactivity spectrum, involving the transfer of H+ and e- from the hydroxylamine TEMPOH to two completely separate molecules. These examples, and those in between, are all analyzed within the same thermodynamic and kinetic framework. A description of the first examples of MS-CPET with C-H bonds uses the same framework and highlights the importance of hydrogen bonding and preorganization. The examples and analyses show that the reactions along the PCET continuum are more similar than they are different, and that attempts to divide these reactions into subcategories can obscure much of the essential chemistry. We hope that developing the many common features of these reactions will help experts and newcomers alike to explore exciting new territories in PCET reactivity.
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Affiliation(s)
- Julia W. Darcy
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Brian Koronkiewicz
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Giovanny A. Parada
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - James M. Mayer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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41
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Gautam RP, Lee YT, Herman GL, Moreno CM, Tse ECM, Barile CJ. Controlling Proton and Electron Transfer Rates to Enhance the Activity of an Oxygen Reduction Electrocatalyst. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201806795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Rajendra P. Gautam
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Yi Teng Lee
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Gabriel L. Herman
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Cynthia M. Moreno
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Edmund C. M. Tse
- Department of Chemistry; The University of Hong Kong; Pokfulam Road Hong Kong SAR Hong Kong
| | - Christopher J. Barile
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
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42
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Gautam RP, Lee YT, Herman GL, Moreno CM, Tse ECM, Barile CJ. Controlling Proton and Electron Transfer Rates to Enhance the Activity of an Oxygen Reduction Electrocatalyst. Angew Chem Int Ed Engl 2018; 57:13480-13483. [DOI: 10.1002/anie.201806795] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Revised: 08/14/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Rajendra P. Gautam
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Yi Teng Lee
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Gabriel L. Herman
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Cynthia M. Moreno
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
| | - Edmund C. M. Tse
- Department of Chemistry; The University of Hong Kong; Pokfulam Road Hong Kong SAR Hong Kong
| | - Christopher J. Barile
- Department of Chemistry; University of Nevada, Reno; 1664 N. Virginia St. Reno NV 89557 USA
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Peters JW, Beratan DN, Bothner B, Dyer RB, Harwood CS, Heiden ZM, Hille R, Jones AK, King PW, Lu Y, Lubner CE, Minteer SD, Mulder DW, Raugei S, Schut GJ, Seefeldt LC, Tokmina-Lukaszewska M, Zadvornyy OA, Zhang P, Adams MW. A new era for electron bifurcation. Curr Opin Chem Biol 2018; 47:32-38. [PMID: 30077080 DOI: 10.1016/j.cbpa.2018.07.026] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/16/2018] [Accepted: 07/18/2018] [Indexed: 11/17/2022]
Abstract
Electron bifurcation, or the coupling of exergonic and endergonic oxidation-reduction reactions, was discovered by Peter Mitchell and provides an elegant mechanism to rationalize and understand the logic that underpins the Q cycle of the respiratory chain. Thought to be a unique reaction of respiratory complex III for nearly 40 years, about a decade ago Wolfgang Buckel and Rudolf Thauer discovered that flavin-based electron bifurcation is also an important component of anaerobic microbial metabolism. Their discovery spawned a surge of research activity, providing a basis to understand flavin-based bifurcation, forging fundamental parallels with Mitchell's Q cycle and leading to the proposal of metal-based bifurcating enzymes. New insights into the mechanism of electron bifurcation provide a foundation to establish the unifying principles and essential elements of this fascinating biochemical phenomenon.
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Affiliation(s)
- John W Peters
- Institute of Biological Chemistry, Washington State University, Pullman WA 99163, United States; Pacific Northwest National Laboratory, Richland, WA 99352, United States.
| | - David N Beratan
- Department of Chemistry and Department of Physics, Duke University, Durham, NC 27708, United States; Department of Biochemistry, Duke University, Durham, NC 27710, United States
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, United States
| | - R Brian Dyer
- Department of Chemistry, Emory University, Atlanta, GA 30322, United States
| | - Caroline S Harwood
- Department of Microbiology, University of Washington, Seattle, WA 98195, United States
| | - Zachariah M Heiden
- Department of Chemistry, Washington State University, Pullman WA 99163, United States
| | - Russ Hille
- Biochemistry Department, University of California at Riverside, Riverside, CA 92521, United States
| | - Anne K Jones
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, United States
| | - Paul W King
- National Renewable Energy Laboratory, Golden, CO 8040, United States
| | - Yi Lu
- Pacific Northwest National Laboratory, Richland, WA 99352, United States; Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Carolyn E Lubner
- National Renewable Energy Laboratory, Golden, CO 8040, United States
| | - Shelley D Minteer
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112, United States
| | - David W Mulder
- National Renewable Energy Laboratory, Golden, CO 8040, United States
| | - Simone Raugei
- Institute of Biological Chemistry, Washington State University, Pullman WA 99163, United States; Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Gerrit J Schut
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, GA 30602, United States
| | - Lance C Seefeldt
- Pacific Northwest National Laboratory, Richland, WA 99352, United States; Department of Chemistry and Biochemistry, Utah State University, Logan, UT 84322, United States
| | | | - Oleg A Zadvornyy
- Institute of Biological Chemistry, Washington State University, Pullman WA 99163, United States
| | - Peng Zhang
- Department of Biochemistry, Duke University, Durham, NC 27710, United States
| | - Michael Ww Adams
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, GA 30602, United States
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Meng K, Medina-Ramos J, Yibeltal-Ashenafi E, Alvarez JC. Interplay of proton and electron transfer to determine concerted behavior in the proton-coupled electron transfer of glutathione oxidation. Phys Chem Chem Phys 2018; 20:17666-17675. [PMID: 29932186 DOI: 10.1039/c8cp01415a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Glutathione (GSH), whose thiol group dictates its redox chemistry, is oxidized to the thiyl radical (GS˙), which rapidly dimerizes to GSSG. Previously, we found that the oxidation rate of GSH by IrCl62- depends on the base (B) concentration and the pKa of its conjugate acid BH+, so that collateral to a stepwise mechanism, the concerted pathway GSH + IrCl62- + B = GS˙ + IrCl63- + BH+ was proposed as the rate determining step. Herein, this investigation is extended to include oxidant-base pairs that render exothermic and endothermic conditions of ΔG°' for electron transfer (ET) and proton transfer (PT). Experiments were conducted by the reaction of GSH with an electrogenerated oxidant M+ and using digital simulations to infer the mechanism. Data analysis shows that despite parallel mechanisms, the concerted one seems to predominate for the oxidant-base pair that renders the most isoenergetic coupled state, whereby a PT with is capable of producing an ET with , as a result of the Nernstian shift of with pKa. In contrast, the stepwise PT-ET appears to dominate when GS- grows in stability as becomes more negative. Understanding the interplay between ET and PT will help in the design of catalysts for energy harvesting processes that rely on proton-coupled electron transfer.
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Affiliation(s)
- Kejie Meng
- Chemistry Department, Virginia Commonwealth University, Richmond, VA 23284, USA.
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Mukherjee A, Pattanayak S, Sen Gupta S, Vanka K. What drives the H-abstraction reaction in bio-mimetic oxoiron-bTAML complexes? A computational investigation. Phys Chem Chem Phys 2018; 20:13845-13850. [PMID: 29717729 DOI: 10.1039/c8cp01333k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Monomeric iron-oxo units have been confirmed as intermediates involved in the C-H bond activation in various metallo-enzymes. Biomimetic oxoiron complexes of the biuret modified tetra-amido macrocyclic ligand (bTAML) have been demonstrated to oxidize a wide variety of unactivated C-H bonds. In the current work, density functional theory (DFT) has been employed to investigate the hydrogen abstraction (HAT) reactivity differences across a series of bTAML complexes. The cause for the differences in the HAT energy barriers has been found to be the relative changes in the energy of the frontier molecular orbitals (FMOs) induced by electronic perturbation.
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Affiliation(s)
- Anagh Mukherjee
- Physical and Material Chemistry Division, CSIR-National Chemical Laboratory, Pune-411008, India.
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Carroll TG, Garwick R, Telser J, Wu G, Ménard G. Synthesis, Characterization, and Electrochemical Analyses of Vanadocene Tetrametaphosphate and Phosphinate Derivatives. Organometallics 2018. [DOI: 10.1021/acs.organomet.7b00797] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Timothy G. Carroll
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Rachel Garwick
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University, Chicago, Illinois 60605, United States
| | - Guang Wu
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Gabriel Ménard
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
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Khosrowabadi Kotyk JF, Hanna CM, Combs RL, Ziller JW, Yang JY. Intramolecular hydrogen-bonding in a cobalt aqua complex and electrochemical water oxidation activity. Chem Sci 2018; 9:2750-2755. [PMID: 29732059 PMCID: PMC5912104 DOI: 10.1039/c7sc04960a] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Accepted: 02/05/2018] [Indexed: 11/30/2022] Open
Abstract
Water oxidation is catalysed in Nature by a redox cofactor embedded in a hydrogen-bonded network designed to orchestrate proton transfer throughout the challenging 4 electron reaction.
Water oxidation is catalysed in Nature by a redox cofactor embedded in a hydrogen-bonded network designed to orchestrate proton transfer throughout the challenging 4 electron reaction. In order to mimic aspects of this microenvironment, [CoLDMA(CH3CN)2][BF4]2 (2) was synthesized, where LDMA is a dipyridyldiamine ligand with two dimethylamine bases in the secondary coordination sphere. Structural characterization of the corresponding aqua complexes establish hydrogen bonding between the bound water and pendant base(s). Cyclic voltammetry of [CoLDMA(CH3CN)2][BF4]2 (2) reveals enhanced oxidative current upon titration with water and controlled potential electrolysis confirms evolution of O2. The related complex [CoLH(CH3CN)2][BF4]2 (1), which has the same primary coordination environment as 2 but lacks pendant bases, is inactive. The structural and electrochemical studies illustrate the role positioned proton relays can play in promoting redox reactivity.
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Affiliation(s)
| | - Caitlin M Hanna
- Department of Chemistry , University of California , Irvine , USA .
| | - Rebecca L Combs
- Department of Chemistry , University of California , Irvine , USA .
| | - Joseph W Ziller
- Department of Chemistry , University of California , Irvine , USA .
| | - Jenny Y Yang
- Department of Chemistry , University of California , Irvine , USA .
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Thiyagarajan SK, Suresh R, Ramanan V, Ramamurthy P. Deciphering the incognito role of water in a light driven proton coupled electron transfer process. Chem Sci 2018; 9:910-921. [PMID: 29629158 PMCID: PMC5873145 DOI: 10.1039/c7sc03161k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 11/10/2017] [Indexed: 01/26/2023] Open
Abstract
Light induced multisite electron proton transfer in two different phenol (simple and phenol carrying an intramolecularly hydrogen bonded base) pendants on acridinedione dye (ADD) and an NADH analogue was studied by following fluorescence quenching dynamics in an ultrafast timescale. In a simple phenol derivative (ADDOH), photo-excited acridinedione acquires an electron from phenol intramolecularly, coupled with the transfer of a proton to solvent water. But in a phenol carrying hydrogen bonded base (ADDDP), both electron and proton transfer occur completely intramolecularly. The sequence of this electron and proton transfer process was validated by discerning the pH dependency of the reaction kinetics. Since photo-excited ADDs are stronger oxidants, the sequential electron first proton transfer mechanism (ETPT) was observed in ADDOH and hence there is no change in the PCET reaction kinetics kETPT ∼ 6.57 × 109 s-1 in the entire pH range (pH 2-12). But the phenol carrying hydrogen bonded base (ADDDP) unleashes concerted electron proton transfer where the PCET reaction rate decreases upon decreasing the pH below its pKa. Noticeably, the concerted EPT process in ADDDP mimics the donor side of photosystem II and it occurs by two distinct pathways: (i) through direct intramolecular hydrogen bonding between the phenol and amine, kDEPT ∼ 12.5 × 1010 s-1 and (ii) through the bidirectional hydrogen bond extended by the water molecule trapped in between the proton donor and acceptor, which mediates the proton transfer and serves as a proton wire, kWMEPT ∼ 2.85 × 1010 s-1. These results unravel the incognito role played by water in mediating the proton transfer process when the structural elements do not favor direct hydrogen bonding between the proton donor and acceptor in a concerted PCET reaction.
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Affiliation(s)
- Senthil Kumar Thiyagarajan
- National Centre for Ultrafast Processes , University of Madras , Taramani Campus , Chennai - 600 113 , India .
| | - Raghupathy Suresh
- National Centre for Ultrafast Processes , University of Madras , Taramani Campus , Chennai - 600 113 , India .
| | - Vadivel Ramanan
- National Centre for Ultrafast Processes , University of Madras , Taramani Campus , Chennai - 600 113 , India .
| | - Perumal Ramamurthy
- National Centre for Ultrafast Processes , University of Madras , Taramani Campus , Chennai - 600 113 , India .
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Caram J, Banera M, Suárez JM, Mirífico M. ELECTROCHEMICAL BEHAVIOUR OF ANTHRAQUINONE DYES IN NON AQUEOUS SOLVENT SOLUTION. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.07.139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Zhang H, Wu W, Mo Y. Study of proton-coupled electron transfer (PCET) with four explicit diabatic states at the ab initio level. COMPUT THEOR CHEM 2017. [DOI: 10.1016/j.comptc.2017.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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