1
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Muley A, Kumbhakar S, Raut R, Mathur S, Roy I, Saini T, Misra A, Maji S. Mononuclear copper(II) complexes with polypyridyl ligands: synthesis, characterization, DNA interactions/cleavages and in vitro cytotoxicity towards human cancer cells. Dalton Trans 2024; 53:11697-11712. [PMID: 38912924 DOI: 10.1039/d4dt00984c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
DNA being the necessary element in cell regeneration, controlled cellular apoptosis via DNA binding/cleaving is considered an approach to combat cancer cells. The widely prescribed metallodrug cisplatin has shown interactions with the guanine-N7 center, and a plethora of complexes are continually developed to enhance crosslinking properties as well as covalent and non-covalent interactions. Two pentadentate ligands, L1 (1-(6-(1H-benzo[d]imidazol-2-yl)pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine) and L2 (1-(6-(1-methyl-1H-benzo[d]imidazol-2-yl)pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine), were synthesized together with their respective copper(II) complexes [1](ClO4)2 and [2](ClO4)2, which crystallized in a trigonal bipyramidal fashion. Different analytical and spectroscopic methods confirmed their formation, and their redox behaviour was also examined. The interactions of salmon sperm DNA (ss-DNA) with these two complexes were explored using absorbance spectroscopy, and they both exhibited a binding affinity (Kb) of ∼104 M-1. Fluorescence quenching experiments with ethidium bromide (EB)-bound DNA (EB-DNA) were also performed, and Stern-Volmer constant (KSV) values of 6.93 × 103 and 2.34 × 104 M-1 for [1](ClO4)2 and [2](ClO4)2, respectively, were obtained. Furthermore, DNA conformational changes due to the interactions of both complexes were validated via circular dichroism. We also assessed the DNA cleavage property of these complexes, which resulted in the linearization of circular plasmid DNA. This finding was supported by studying the growth of MDA-MB-231 breast cancer cells upon treatment with both Cu(II) complexes; IC50 values of 5.34 ± 1.02 μM and 0.83 ± 0.18 μM were obtained for [1](ClO4)2 and [2](ClO4)2, respectively. This validates their affinity towards DNA, and these insights can be further utilized for non-platinum based economical metallodrug development based on first row transition metals.
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Affiliation(s)
- Arabinda Muley
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Sadananda Kumbhakar
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Rajnikant Raut
- Department of Biotechnology, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Shobhit Mathur
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Indrajit Roy
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Taruna Saini
- Department of Biotechnology, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Ashish Misra
- Department of Biotechnology, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
| | - Somnath Maji
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502284, Telangana, India.
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2
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Su Q, Li Y, Han J, Zhou X, Liu S. Density Functional Theory Calculations on Fluorescence-Enhanced Mechanisms of the Optical Sensor for Zinc Ions, ADPA. Chemphyschem 2024; 25:e202400140. [PMID: 38497816 DOI: 10.1002/cphc.202400140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/17/2024] [Accepted: 03/18/2024] [Indexed: 03/19/2024]
Abstract
N-(9-anthracenylmethyl)-N-(2-pyridinylmethyl)-2-pyridinemethanamine (ADPA) as a specific ion sensor for Zn2+ has been widely applied. Although the photo-induced electron transfer (PET) mechanism was proposed previously, its fluorescence-enhanced effect still remains somewhat ambiguous, according to unknown influences of non-radiative energy decay pathways, such as intersystem crossing and internal conversion. Herein, a thorough study using density functional theory has been performed for low-lying electronic states of the ADPA monomer and hydrated ADPA-Zn2+ complex. Based on interfragment charge transfer analyses, we quantitatively calculated the amount of transferred electrons in the monomer and complex, providing solid evidences for the PET mechanism and in line with the conclusion of frontier molecular orbital analyses. Moreover, the ISC process of S1→T2 was confirmed to play a considerable role in the excitation energy relaxation process of the ADPA monomer, but this influence was significantly suppressed in the hydrated ADPA-Zn2+ complex. These results provide additional clues for the design of new metal ion-specific fluorescence probes.
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Affiliation(s)
- Quyan Su
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Yuanming Li
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Jia Han
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Xiaoguo Zhou
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Shilin Liu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, 230026, China
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3
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Tanjedrew N, Thammanatpong K, Surawatanawong P, Chakthranont P, Chantarojsiri T, Unjarern T, Kiatisevi S. Tunable Metal-Free Imidazole-Benzimidazole Electrocatalysts for Oxygen Reduction in Aqueous Solutions. Chemistry 2024; 30:e202302854. [PMID: 37924228 DOI: 10.1002/chem.202302854] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/03/2023] [Accepted: 11/03/2023] [Indexed: 11/06/2023]
Abstract
A series of metal-free imidazole-benzimidazole catalysts (ImBenz-H, ImBenz-NO2 , ImBenz-OCH3 ) for oxygen reduction reaction (ORR) were prepared. We demonstrate that the electrocatalytic O2 reduction by ImBenz-NO2 with the electron-withdrawing group showed high selectivity toward H2 O with the number of electrons transferred (n=3.7) in a neutral aqueous solution. The highest ORR selectivity toward H2 O2 was achieved using ImBenz-H (n=2.4) in an alkaline solution. Electrochemical studies of reaction kinetics disclosed that the highest turnover frequencies were obtained from ImBenz-H in both neutral and alkaline aqueous solutions. The results prove that the ORR selectivity is tunable by modulating the substituent of the ImBenz catalysts. Furthermore, DFT calculations suggested that the ORR mechanism of ImBenz-H involves the electron transfer from imidazole-benzimidazole to O2 resulting in the formation of H2 O2 which supports the redox active properties of the catalysts ImBenz.
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Affiliation(s)
- Narisara Tanjedrew
- Department of Chemistry and, Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Kittimeth Thammanatpong
- Department of Chemistry and, Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Panida Surawatanawong
- Department of Chemistry and, Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Pongkarn Chakthranont
- National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), 111 Thailand Science Park, Pathum Thani, 12120, Thailand
| | - Teera Chantarojsiri
- Department of Chemistry and, Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Takdanai Unjarern
- Department of Chemistry and, Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Supavadee Kiatisevi
- Department of Chemistry and, Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
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4
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Phiromphu N, Juthathan M, Suktanarak P, Sukwattanasinitt M, Tuntulani T, Leeladee P. Selective copper-catalysed atom transfer radical addition (ATRA) in water under environmentally benign conditions. Dalton Trans 2023; 52:14235-14241. [PMID: 37766676 DOI: 10.1039/d3dt02044d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
Simple and green conditions for copper-catalysed ATRA reactions in water have been developed. Firstly, [Cu(ADPA)(H2O)(ClO4)2] (1b, ADPA = 9-[(2,2'-dipicolylamino)methyl]anthracene) was demonstrated to be capable of selectively catalysing the ATRA of CCl4 to styrene using L-ascorbic acid (AsH2) as a reducing agent in organic solvent mixtures under ambient atmosphere. Mechanistic investigation suggested that our ATRA reaction proceeded via a single-electron transfer (SET) mechanism through an inner-sphere complex, which is consistent with the widely accepted mechanism for copper-catalysed ATRA. To perform the reaction in water as a sole solvent, a biocompatible surfactant (2 wt% Tween 20 or Tween 80) was added to improve solubility and increase the local concentration of organic reagents and the copper catalyst. Without the need for a complicated oxygen-free set-up, the ATRA reaction catalysed by this simple aqueous-dispersed system can be performed at a mild temperature (60 °C) and a relatively short reaction time (6 h) using 1 mol% of the catalyst. Furthermore, this facile protocol is also applicable for other alkene substrates demonstrated in this work, resulting in satisfactory to excellent substrate conversion and product yields.
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Affiliation(s)
- Nutchanikan Phiromphu
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
| | - Methasit Juthathan
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
| | - Pattira Suktanarak
- Faculty of Sport and Health Sciences, Thailand National Sports University Lampang Campus, Lampang, 52100, Thailand
| | | | - Thawatchai Tuntulani
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
| | - Pannee Leeladee
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
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5
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Chowdhury SN, Biswas S, Das S, Biswas AN. Kinetic and mechanistic investigations of dioxygen reduction by a molecular Cu(II) catalyst bearing a pentadentate amidate ligand. Dalton Trans 2023; 52:11581-11590. [PMID: 37548356 DOI: 10.1039/d3dt02194g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
A pentadentate Cu(II) complex, [CuII(dpaq)](ClO4) (1), featuring a redox active ligand, H-dpaq (H-dpaq = 2-[bis(pyridine-2-ylmethyl)]amino-N-quinolin-8-yl-acetamidate), catalyses four-electron reduction of dioxygen by decamethylferrocene (Fc*) in the presence of trifluoroacetic acid (CF3COOH) in acetone at 298 K. No catalytic oxygen reduction was observed in the presence of stronger Brønsted acids than CF3COOH, such as perchloric acid (HClO4) or trifluoromethanesulphonic acid (HOTf). In contrast, facile catalytic reduction of O2 occurs by Fc* with 1 and HClO4 or HOTf in dimethylformamide (DMF). The use of CF3COOH as the proton source in DMF results in the suppression of O2 reduction under otherwise identical reaction conditions. While the O2 reduction reactions in DMF are linearly dependent on the pKa of Brønsted acids, the acid dependence on catalytic O2-reduction reactivity by 1 in acetone showed complete reversal. Cyclic voltammetry studies using p-chloranil as the probe substrates in the presence of acids in the solvents reveal that the strengths of the protonic acids increase significantly in acetone compared to that in DMF. The amidate-N in [CuII(dpaq)](ClO4) (1) undergoes protonation in the presence of HClO4 or HOTf in DMF to form [CuII(H-dpaq)]2+ (1-H+), but not in the presence of CF3COOH. Enhanced acid strength of CF3COOH in acetone, however, effectively protonates 1 and triggers O2 reduction. Protonation of 1 with HClO4 or HOTf in acetone results in the change of its coordination environment, and this protonated species does not trigger O2 reduction. Detailed kinetic studies indicate that 1-H+ undergoes reduction by two-electrons and the reduced species binds O2 to form a Cu(II)-superoxo intermediate. This is followed by a rate-determining proton-coupled electron-transfer (PCET) reduction to generate the Cu(II)-hydroperoxo intermediate. While catalytic O2 reduction in acetone occurs predominantly via a 4e-/4H+ pathway, product selectivity (H2O vs. H2O2) in DMF depends upon the concentration of the reductant (Fc*). While dioxygen reduction to H2O2 is favoured at low [Fc*], mechanistic studies suggest that O2 reduction with high [Fc*] proceeds via a [2e- + 2e-] mechanism, where the released H2O2 during catalysis is further reduced to water.
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Affiliation(s)
- Srijan Narayan Chowdhury
- Department of Chemistry, National Institute of Technology Sikkim, Ravangla, South Sikkim 737139, India.
| | - Sachidulal Biswas
- Department of Chemistry, National Institute of Technology Sikkim, Ravangla, South Sikkim 737139, India.
| | - Saikat Das
- Department of Chemistry, National Institute of Technology Sikkim, Ravangla, South Sikkim 737139, India.
| | - Achintesh N Biswas
- Department of Chemistry, National Institute of Technology Sikkim, Ravangla, South Sikkim 737139, India.
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6
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Chimlert J, Suktanarak P, Plainpan N, Paokhan M, Tuntulani T, Leeladee P. Cycloalkane Oxidation Catalyzed by Copper‐based Catalysts with H
2
O
2
under Mild Conditions. ChemistrySelect 2023. [DOI: 10.1002/slct.202204776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Affiliation(s)
- Jantira Chimlert
- Department of Chemistry Faculty of Science Chulalongkorn University Bangkok 10330 Thailand
| | - Pattira Suktanarak
- Faculty of Sport and Health Sciences Thailand National Sport University Lampang Campus Lampang 52100 Thailand
| | - Nukorn Plainpan
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO) École Polytechnique Fédérale de Lausanne (EPFL) Station 6 1015 Lausanne Switzerland
| | - Mantana Paokhan
- Department of Chemistry Faculty of Science Chulalongkorn University Bangkok 10330 Thailand
| | - Thawatchai Tuntulani
- Department of Chemistry Faculty of Science Chulalongkorn University Bangkok 10330 Thailand
| | - Pannee Leeladee
- Department of Chemistry Faculty of Science Chulalongkorn University Bangkok 10330 Thailand
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7
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Osawa S, Kurokawa S, Otsuka H. Controlled polymerization of metal complex monomers - fabricating random copolymers comprising different metal species and nano-colloids. Chem Commun (Camb) 2022; 58:5273-5276. [PMID: 35393983 DOI: 10.1039/d1cc07265j] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Acrylate monomers with metal complexes were designed to build polymer metal complexes. The ideal copolymerization of monomers with zinc and platinum was performed to obtain random copolymers with a feeding metal composition. The successful nano-colloid preparation from the polymers further highlighted the potential of the method for building multimetallic materials.
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Affiliation(s)
- Shigehito Osawa
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku-ku, Tokyo, 162-8601, Japan. .,Water Frontier Research Center (WaTUS), Research Institute for Science and Technology, Tokyo University of Science1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Sosuke Kurokawa
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Hidenori Otsuka
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku-ku, Tokyo, 162-8601, Japan. .,Water Frontier Research Center (WaTUS), Research Institute for Science and Technology, Tokyo University of Science1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Department of Chemistry, Graduate School of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku-ku, Tokyo, 162-8601, Japan
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8
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Suktanarak P, Leeladee P, Tuntulani T. Oxidative ligand cleavage in a copper(
II
) complex containing aniline moiety induced by copper(
II
) perchlorate in acetonitrile. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Pattira Suktanarak
- Faculty of Sport and Health Sciences Thailand National Sports University Lampang Campus Lampang Thailand
| | - Pannee Leeladee
- Department of Chemistry Faculty of Science, Chulalongkorn University Bangkok Thailand
| | - Thawatchai Tuntulani
- Department of Chemistry Faculty of Science, Chulalongkorn University Bangkok Thailand
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9
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Osawa S, Kitanishi K, Kiuchi M, Shimonaka M, Otsuka H. Accelerated Redox Reaction of Hydrogen Peroxide by Employing Locally Concentrated State of Copper Catalysts on Polymer Chain. Macromol Rapid Commun 2021; 42:e2100274. [PMID: 34292631 DOI: 10.1002/marc.202100274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/13/2021] [Indexed: 12/21/2022]
Abstract
Copper complexes act as catalysts for redox reactions to generate reactive oxygen species that destroy biomolecules and, therefore, are utilized to design drugs including antitumor and antibacterial medicines. Especially, catalytic reaction for hydrogen peroxide decomposition is important because it includes the process for generating highly toxic hydroxyl radical, i.e., Fenton-like reaction. Considering that multicoppers/hydrogen peroxide species are the important intermediates for the redox reaction, herein a polymer having copper complexes in the side chains is designed to facilitate the formation of the intermediates by building locally concentrated state of the copper complexes. The polymer increases their catalytic activities for hydrogen peroxide decomposition and promotes reactive oxygen species' generation, eventually leading to higher antibacterial activity. This reveals the virtue of building a locally concentrated state of catalysts on polymers toward drug design with low amounts of transition metals.
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Affiliation(s)
- Shigehito Osawa
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Kenichi Kitanishi
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Maho Kiuchi
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Motoyuki Shimonaka
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Hidenori Otsuka
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.,Water Frontier Science and Technology Research Center, Research Institute for Science and Technology, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
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10
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Chowdhury SN, Biswas S, Das P, Paul S, Biswas AN. Oxygen Reduction Assisted by the Concert of Redox Activity and Proton Relay in a Cu(II) Complex. Inorg Chem 2020; 59:14012-14022. [PMID: 32916051 DOI: 10.1021/acs.inorgchem.0c01776] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A copper complex, [Cu(dpaq)](ClO4) (1), of a monoanionic pentadentate amidate ligand (dpaq) has been isolated and characterized to study its efficacy toward electrocatalytic reduction of oxygen in neutral aqueous medium. The Cu(II) mononuclear complex, poised in a distorted trigonal bipyramidal structure, reduces oxygen at an onset potential of 0.50 V vs RHE. Kinetics study by hydrodynamic voltammetry and chronoamperometry suggests a stepwise mechanism for sequential reduction of O2 to H2O2 to H2O at a single-site Cu-catalyst. The foot-of-the-wave analysis records a turnover frequency of 5.65 × 102 s-1. At pH 7.0, complex 1 undergoes a quasi-reversible mixed metal-ligand-based reduction and triggers the reduction of dioxygen to water. Electrochemical studies in tandem with quantum chemical investigation, conducted at different redox states, portray the active participation of ligand in completing the process of proton-coupled electron transfer internally. The protonated carboxamido moiety acts as a proton relay, while the quinoline-based orbital supplies the necessary redox equivalent for the conversion of complex 1 to Cu(II)-hydroperoxo species. Thus, a suitable combination of redox non-innocence and proton shuttling functionality in the ligand makes it an effective electron-proton-transfer mediator and subsequently assists the process of oxygen reduction.
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Affiliation(s)
- Srijan Narayan Chowdhury
- Department of Chemistry, National Institute of Technology Sikkim, Barfung Block, Ravangla, South Sikkim 737139, India
| | - Sachidulal Biswas
- Department of Chemistry, National Institute of Technology Sikkim, Barfung Block, Ravangla, South Sikkim 737139, India
| | - Purak Das
- Department of Chemistry, Rishi Bankim Chandra College for Women, Naihati 743165, India
| | - Satadal Paul
- Department of Science and Humanities, Darjeeling Polytechnic, Kurseong 734203, India
| | - Achintesh N Biswas
- Department of Chemistry, National Institute of Technology Sikkim, Barfung Block, Ravangla, South Sikkim 737139, India
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