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Zhang H, Liang Q, Xie K. How to rationally design homogeneous catalysts for efficient CO 2 electroreduction? iScience 2024; 27:108973. [PMID: 38327791 PMCID: PMC10847752 DOI: 10.1016/j.isci.2024.108973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024] Open
Abstract
Electrified converting CO2 into valuable fuels and chemicals using a homogeneous electrochemical CO2 reduction (CO2ER) approach simplifies the operation, providing a potential option for decoupling energy harvesting and renewable chemical production. These merits benefit the scenarios where decentralization and intermittent power are key factors. This perspective aims to provide an overview of recent progress in homogeneous CO2ER. We introduce firstly the fundamentals chemistry of the homogeneous CO2ER, followed by a summary of the crucial factors and the important criteria broadly employed for evaluating the performance. We then highlight the recent advances in the most widely explored transition-metal coordinate complexes for the C1 and multicarbon (C2+) products from homogeneous CO2ER. Finally, we summarize the remaining challenges and opportunities for developing homogeneous electrocatalysts for efficient CO2ER. This perspective is expected to favor the rational design of efficient homogeneous electrocatalysts for selective CO2ER toward renewable fuels and feedstocks.
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Affiliation(s)
- Hui Zhang
- International Center for Quantum and Molecular Structures, College of Sciences, Shanghai University, Shanghai 200444, P.R. China
| | - Qinghua Liang
- Key Laboratory of Rare Earths, Chinese Academy of Sciences, Ganzhou, Jiangxi 341000, P.R. China
- Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou, Jiangxi 341000, P.R. China
| | - Ke Xie
- Department of Chemistry, Northwestern Universiy, Evanston, IL 60208, USA
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2
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Ameskal M, Taakili R, Gulyaeva ES, Duhayon C, Willot J, Lugan N, Lepetit C, Valyaev DA, Canac Y. Phosphine-NHC-Phosphonium Ylide Pincer Ligand: Complexation with Pd(II) and Unconventional P-Coordination of the Ylide Moiety. Inorg Chem 2023. [PMID: 37996076 DOI: 10.1021/acs.inorgchem.3c03025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
An efficient synthesis of two pincer preligands [Ph2PCH(R)ImCH2CH2CH2PPh3]X2 (R = H, X = OTf; R = Ph, X = BF4) was developed. Subsequent reactions with PdCl2 and an excess of Cs2CO3 led to the formation of highly stable cationic ortho-metalated Pd(II) complexes [(P,C,C,C)Pd]X exhibiting phosphine, NHC, phosphonium ylide, and σ-aryl donor extremities. The protonation of one of the latter complexes with R = H affords the Pd(II) complex [(P,C,C)Pd(MeCN)](OTf)2 bearing an unprecedented nonsymmetrical NHC core pincer scaffold with a 5,6-chelating framework. The overall donor properties of this phosphine-NHC-phosphonium ylide ligand were estimated using the experimental νCN stretching frequency in the corresponding [(P,C,C)Pd(CNtBu](OTf)2 derivative and were shown to be competitive with the related bis(NHC)-phosphonium ylide and phenoxy-NHC-phosphonium ylide pincers. The presence of a phenyl substituent in the bridge between phosphine and NHC moieties in the ortho-metalated complex [(P,C,C,C)Pd](BF4) makes possible the deprotonation of this position using LDA to provide a persistent zwitterionic complex [(P,C,C,C)Pd] featuring a rare P-coordinated phosphonium ylide moiety in addition to a conventional C-coordinated one. The comparison of the 31P and 13C NMR data for these C- and P-bound phosphonium ylide fragments within the same molecule was performed for the first time, and the bonding situation in both cases was studied in detail by QTAIM and ELF topological analyses.
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Affiliation(s)
- Mohammad Ameskal
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Rachid Taakili
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Ekaterina S Gulyaeva
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
- A. N. Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28/1 Vavilov str., GSP-1, B-334, Moscow 119334, Russia
| | - Carine Duhayon
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Jérémy Willot
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Noël Lugan
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Christine Lepetit
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Dmitry A Valyaev
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Yves Canac
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
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3
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Khurshid A, Tanveer T, Hafeez K, Ahmed M, Akhtar Z, Zafar MN. Palladium-anchored donor-flexible pyridylidene amide (PYA) electrocatalysts for CO 2 reduction. RSC Adv 2023; 13:34817-34825. [PMID: 38035229 PMCID: PMC10686039 DOI: 10.1039/d3ra06477h] [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] [Received: 09/22/2023] [Accepted: 11/15/2023] [Indexed: 12/02/2023] Open
Abstract
The conversion of CO2 into CO as a substitute for processing fossil fuels to produce hydrocarbons is a sustainable, carbon neutral energy technology. However, the electrochemical reduction of CO2 into a synthesis gas (CO and H2) at a commercial scale requires an efficient electrocatalyst. In this perspective, a series of six new palladium complexes with the general formula [Pd(L)(Y)]Y, where L is a donor-flexible PYA, N2,N6-bis(1-ethylpyridin-4(1H)-ylidene)pyridine-2,6-dicarboxamide, N2,N6-bis(1-butylpyridin-4(1H)-ylidene)pyridine-2,6-dicarboxamide, or N2,N6-bis(1-benzylpyridin-4(1H)-ylidene)pyridine-2,6-dicarboxamide, and Y = OAc or Cl-, were utilized as active electrocatalysts for the conversion of CO2 into a synthesis gas. These palladium(ii) pincer complexes were synthesized from their respective H-PYA proligands using 1,8-diazobicyclo[5.4.0]undec-7-ene (DBU) or sodium acetate as a base. All the compounds were successfully characterized by various physical methods of analysis, such as proton and carbon NMR, FTIR, CHN, and single-crystal XRD. The redox chemistry of palladium complexes toward carbon dioxide activation suggested an evident CO2 interaction with each Pd(ii) catalyst. [Pd(N2,N6-bis(1-ethylpyridin-4(1H)-ylidene)pyridine-2,6-dicarboxamide)(Cl)]Cl showed the best electrocatalytic activity for CO2 reduction into a synthesis gas under the acidic condition of trifluoracetic acid (TFA) with a minimum overpotential of 0.40 V, a maximum turnover frequency (TOF) of 101 s-1, and 58% FE of CO. This pincer scaffold could be stereochemically tuned with the exploration of earth abundant first row transition metals for further improvements in the CO2 reduction chemistry.
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Affiliation(s)
- Afshan Khurshid
- Department of Chemistry, Quaid-i-Azam University Islamabad 45320 Pakistan
| | - Tania Tanveer
- Department of Chemistry, Quaid-i-Azam University Islamabad 45320 Pakistan
| | - Komal Hafeez
- Department of Chemistry, Quaid-i-Azam University Islamabad 45320 Pakistan
| | - Maqsood Ahmed
- Materials Chemistry Laboratory, Department of Chemistry, The Islamia University of Bahawalpur 63100 Pakistan
| | - Zareen Akhtar
- Department of Chemistry, Quaid-i-Azam University Islamabad 45320 Pakistan
| | - M Naveed Zafar
- Department of Chemistry, Quaid-i-Azam University Islamabad 45320 Pakistan
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Chakrabarti S, Woods TJ, Mirica LM. Insights into the Mechanism of CO 2 Electroreduction by Molecular Palladium-Pyridinophane Complexes. Inorg Chem 2023; 62:16801-16809. [PMID: 37787756 DOI: 10.1021/acs.inorgchem.3c02236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Herein, we report the synthesis, characterization, and electrocatalytic CO2 reduction activity of a series of Pd(II) complexes supported by tetradentate pyridinophane ligands. In particular, we focus on the electrocatalytic CO2 reduction activity of a Pd(II) complex supported by the mixed hard--soft donor ligand 2,11-dithia[3.3](2,6)pyridinophane (N2S2). We also provide spectroscopic evidence of a CO-induced decomposition pathway for the same catalyst, which provides insights into catalyst poisoning for molecular Pd CO2 reduction electrocatalysts.
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Affiliation(s)
- Sagnik Chakrabarti
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Toby J Woods
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Liviu M Mirica
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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5
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Keskin E, Arslan H. Synthesis, crystal structure, DFT calculations, and Hirshfeld surface analysis of an NNN pincer type compound. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2023.135252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
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Kiraev SR, Mathieu E, Kovacs D, Wells JAL, Tomar M, Andres J, Borbas KE. Improved emission of Yb( iii) ions in triazacyclononane-based macrocyclic ligands compared to cyclen-based ones. Dalton Trans 2022; 51:16596-16604. [DOI: 10.1039/d2dt02266d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Yb(iii) complexes were synthesised from ligands with a 1,4,7-triazacyclononane (tacn) macrocyclic core. Tacn-based compounds equipped with 2 picolinate arms were more emissive than their tricarboxamide-cyclen analogues carrying the same antenna.
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Affiliation(s)
- Salauat R. Kiraev
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
| | - Emilie Mathieu
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
| | - Daniel Kovacs
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
| | - Jordann A. L. Wells
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
| | - Monika Tomar
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
| | - Julien Andres
- Chemistry and Chemical Engineering Section, Ecole Polytechnique Fédérale de Lausanne (EPFL), BCH 3311, CH-1015, Lausanne, Switzerland
| | - K. Eszter Borbas
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
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7
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Highly active electrocatalytic CO2 reduction with manganese N-heterocyclic carbene pincer by para electronic tuning. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2021.06.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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8
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Huang C, Liu J, Huang HH, Ke Z. Recent progress in electro- and photo-catalytic CO2 reduction using N-heterocyclic carbene transition metal complexes. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Barlow JM, Ziller JW, Yang JY. Inhibiting the Hydrogen Evolution Reaction (HER) with Proximal Cations: A Strategy for Promoting Selective Electrocatalytic Reduction. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01527] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jeffrey M. Barlow
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Joseph W. Ziller
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jenny Y. Yang
- Department of Chemistry, University of California, Irvine, California 92697, United States
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Kinzel NW, Werlé C, Leitner W. Transition Metal Complexes as Catalysts for the Electroconversion of CO 2 : An Organometallic Perspective. Angew Chem Int Ed Engl 2021; 60:11628-11686. [PMID: 33464678 PMCID: PMC8248444 DOI: 10.1002/anie.202006988] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 08/11/2020] [Indexed: 12/17/2022]
Abstract
The electrocatalytic transformation of carbon dioxide has been a topic of interest in the field of CO2 utilization for a long time. Recently, the area has seen increasing dynamics as an alternative strategy to catalytic hydrogenation for CO2 reduction. While many studies focus on the direct electron transfer to the CO2 molecule at the electrode material, molecular transition metal complexes in solution offer the possibility to act as catalysts for the electron transfer. C1 compounds such as carbon monoxide, formate, and methanol are often targeted as the main products, but more elaborate transformations are also possible within the coordination sphere of the metal center. This perspective article will cover selected examples to illustrate and categorize the currently favored mechanisms for the electrochemically induced transformation of CO2 promoted by homogeneous transition metal complexes. The insights will be corroborated with the concepts and elementary steps of organometallic catalysis to derive potential strategies to broaden the molecular diversity of possible products.
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Affiliation(s)
- Niklas W. Kinzel
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470Mülheim an der RuhrGermany
- Institut für Technische und Makromolekulare Chemie (ITMC)RWTH Aachen UniversityWorringer Weg 252074AachenGermany
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470Mülheim an der RuhrGermany
- Ruhr University BochumUniversitätsstr. 15044801BochumGermany
| | - Walter Leitner
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470Mülheim an der RuhrGermany
- Institut für Technische und Makromolekulare Chemie (ITMC)RWTH Aachen UniversityWorringer Weg 252074AachenGermany
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11
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Kovacs D, Kocsi D, Wells JAL, Kiraev SR, Borbas KE. Electron transfer pathways in photoexcited lanthanide(iii) complexes of picolinate ligands. Dalton Trans 2021; 50:4244-4254. [PMID: 33688904 DOI: 10.1039/d1dt00616a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A series of luminescent lanthanide(iii) complexes consisting of 1,4,7-triazacyclononane frameworks and three secondary amide-linked carbostyril antennae were synthesised. The metal binding sites were augmented with two pyridylcarboxylate donors yielding octadentate ligands. The antennae carried methyl, methoxymethyl or trifluoromethyl substituents in their 4-positions, allowing for a range of excited state energies and antenna electronic properties. The 1H NMR spectra of the Eu(iii) complexes were found to be analogous to each other. Similar results were obtained in the solid-state by single-crystal X-ray crystallography, which showed the structures to have nine-coordinate metal ions with heavily distorted tricapped trigonal prismatic geometries. Steady-state and time-resolved luminescence spectroscopy showed that the antennae could sensitize both Tb(iii) and Eu(iii), however, quantum yields were lower than in other octadentate complexes lacking pyridylcarboxylate. Complexes with more electron-poor pyridines were less emissive even when equipped with the same antenna. The oxidation and reduction potentials of the antennae and the pyridinecarboxylates, respectively, were determined by cyclic voltammetry. The obtained values were consistent with electron transfer from the excited antenna to the pyridine providing a previously unexplored quenching pathway that could efficiently compete with energy transfer to the lanthanide. These results show the crucial impact that photophysically innocent ligand binding sites can have on lanthanide luminescence.
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Affiliation(s)
- Daniel Kovacs
- Department of Chemistry, Ångström Laboratory, Box 523, Uppsala University, 75120, Uppsala, Sweden.
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12
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Kinzel NW, Werlé C, Leitner W. Übergangsmetallkomplexe als Katalysatoren für die elektrische Umwandlung von CO
2
– eine metallorganische Perspektive. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202006988] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Niklas W. Kinzel
- Max-Planck-Institut für Chemische Energiekonversion Stiftstraße 34–36 45470 Mülheim an der Ruhr Deutschland
- Institut für Technische und Makromolekulare Chemie (ITMC) RWTH Aachen University Worringer Weg 2 52074 Aachen Deutschland
| | - Christophe Werlé
- Max-Planck-Institut für Chemische Energiekonversion Stiftstraße 34–36 45470 Mülheim an der Ruhr Deutschland
- Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Walter Leitner
- Max-Planck-Institut für Chemische Energiekonversion Stiftstraße 34–36 45470 Mülheim an der Ruhr Deutschland
- Institut für Technische und Makromolekulare Chemie (ITMC) RWTH Aachen University Worringer Weg 2 52074 Aachen Deutschland
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13
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Wang Y, Zhang B, Guo S. Transition Metal Complexes Supported by N‐Heterocyclic Carbene‐Based Pincer Platforms: Synthesis, Reactivity and Applications. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000911] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Yidan Wang
- Department of Chemistry Capital Normal University Beijing 100048 China
| | - Bo Zhang
- Department of Chemistry Capital Normal University Beijing 100048 China
| | - Shuai Guo
- Department of Chemistry Capital Normal University Beijing 100048 China
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14
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Abstract
The decrease of total amount of atmospheric CO2 is an important societal challenge in which CO2 reduction has an important role to play. Electrocatalytic CO2 reduction with homogeneous catalysts is based on highly tunable catalyst design and exploits an abundant C1 source to make valuable products such as fuels and fuel precursors. These methods can also take advantage of renewable electricity as a green reductant. Mn-based catalysts offer these benefits while incorporating a relatively cheap and abundant first-row transition metal. Historically, interest in this field started with Mn(bpy-R)(CO)3X, whose performance matched that of its Re counterparts while achieving substantially lower overpotentials. This review examines an emerging class of homogeneous Mn-based electrocatalysts for CO2 reduction, Mn complexes with meridional tridentate coordination also known as Mn pincers, most of which contain redox-active ligands that enable multi-electron catalysis. Although there are relatively few examples in the literature thus far, these catalysts bring forth new catalytic mechanisms not observed for the well-established Mn(bpy-R)(CO)3X catalysts, and show promising reactivity for future studies.
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Hu G, Jiang JJ, Kelly HR, Matula AJ, Wu Y, Romano N, Mercado BQ, Wang H, Batista VS, Crabtree RH, Brudvig GW. Surprisingly big linker-dependence of activity and selectivity in CO 2 reduction by an iridium(i) pincer complex. Chem Commun (Camb) 2020; 56:9126-9129. [PMID: 32779668 DOI: 10.1039/d0cc03207g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Here, we report the quantitative electroreduction of CO2 to CO by a PNP-pincer iridium(i) complex bearing amino linkers in DMF/water. The electrocatalytic properties greatly depend on the choice of linker within the ligand. The complex 3-N is far superior to the analogues with methylene and oxygen linkers, showing higher activity and better selectivity for CO2 over proton reduction.
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Affiliation(s)
- Gongfang Hu
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Jianbing Jimmy Jiang
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, USA.
| | - H Ray Kelly
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Adam J Matula
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Yueshen Wu
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Neyen Romano
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Brandon Q Mercado
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Hailiang Wang
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Robert H Crabtree
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
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16
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Yang Y, Zhang Z, Chang X, Zhang YQ, Liao RZ, Duan L. Highly Active Manganese-Based CO 2 Reduction Catalysts with Bulky NHC Ligands: A Mechanistic Study. Inorg Chem 2020; 59:10234-10242. [PMID: 32585094 DOI: 10.1021/acs.inorgchem.0c01364] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Because of the strong σ-donor and weak π-acceptor of the N-heterocyclic carbene (NHC), Mn-NHC complexes were found to be active for the reduction of CO2 to CO with high activity. However, some NHC-based manganese complexes showed low catalytic activity and required very negative potentials. We report herein that complex fac-[MnI(bis-MesNHC)(CO)3Br] [1; bis-MesNHC = 3,3-bis(2,4,6-trimethylphenyl)-(1,1'-diimidazolin-2,2'-diylidene)methane] could catalyze the electrochemical reduction of CO2 to CO with high activity (TOFmax = 3180 ± 6 s-1) at a less negative potential. Due to the introduction of the bulky Mes groups, a one-electron-reduced intermediate {[Mn0(bis-MesNHC)(CO)3]0 (2•)} was isolated as a packed "dimer" and crystallographically characterized. Stopped-flow Fourier-transform infrared spectroscopy was used to prove the direct reaction between doubly reduced intermediate fac-[Mn(bis-MesNHC)(CO)3]- and CO2; the tetracarbonyl Mn complex [Mn+(bis-MesNHC)(CO)4]+ ([2-CO]+) was captured, and its further reduction proposed as the rate-limiting step.
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Affiliation(s)
- Yong Yang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, P. R. China
| | - Zhenyu Zhang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, P. R. China
| | - Xiaoyong Chang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, P. R. China
| | - Ya-Qiong Zhang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Lele Duan
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, P. R. China.,Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Energy Materials for Electric Power, Southern University of Science and Technology (SUSTech), Shenzhen 518055, P. R. China
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17
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Schwartz TM, Burnett ME, Green KN. Electronic influence of substitution on the pyridine ring within NNN pincer-type molecules. Dalton Trans 2020; 49:2356-2363. [PMID: 32022045 PMCID: PMC7323500 DOI: 10.1039/c9dt04714j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Pincer molecules are of increasing interest due to the modular nature of modification and range of reactivity observed when coordinated to metal ions. A subset within the family of pincer molecules use a pyridine group to bridge the outer two arms as well as provide a N-donor atom for metal binding. While the arm appendages have been studied extensively, little research has been conducted on the electronic effects of the central, substituted pyridine systems. Therefore, a series of NNN pincer-type ligands with substitution on the 4-position of the pyridine ring with -OH, -OBn, -H, -Cl, and -NO2 functional groups were synthesized and characterized through NMR spectroscopy and ESI-HRMS. Each pincer was metalated with Cu(ii) salts and evaluated through X-ray diffraction analysis, cyclic voltammetry, and density functional theory analysis. The results indicate that the relatively unstudied -OBn group demonstrates both electron-withdrawing (XRD bond lengths) and electron-donating (NMR spectroscopy) properties. The -NO2 pincer ligand shows a redox event within experimental windows evaluated, in contrast to the other congeners studied. In addition, electron-donating groups increase the electron density around the Cu(ii) center based on DFT studies and cyclic voltammetry. These findings can be applied to other pyridine-based pincer systems when considering ligand design and warrants future characterization of 4-position substituted pyridines.
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Affiliation(s)
- Timothy M Schwartz
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
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Franco F, Rettenmaier C, Jeon HS, Roldan Cuenya B. Transition metal-based catalysts for the electrochemical CO2 reduction: from atoms and molecules to nanostructured materials. Chem Soc Rev 2020; 49:6884-6946. [DOI: 10.1039/d0cs00835d] [Citation(s) in RCA: 161] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
An overview of the main strategies for the rational design of transition metal-based catalysts for the electrochemical conversion of CO2, ranging from molecular systems to single-atom and nanostructured catalysts.
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Affiliation(s)
- Federico Franco
- Department of Interface Science
- Fritz-Haber Institute of the Max Planck Society
- 14195 Berlin
- Germany
| | - Clara Rettenmaier
- Department of Interface Science
- Fritz-Haber Institute of the Max Planck Society
- 14195 Berlin
- Germany
| | - Hyo Sang Jeon
- Department of Interface Science
- Fritz-Haber Institute of the Max Planck Society
- 14195 Berlin
- Germany
| | - Beatriz Roldan Cuenya
- Department of Interface Science
- Fritz-Haber Institute of the Max Planck Society
- 14195 Berlin
- Germany
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19
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Nakamura S, Takase T, Oyama D. Synthesis of 2,6-di(1,8-naphthyridin-2-yl)pyridines functionalized at the 4-position: Building blocks for suitable metal complex-based dyes. SYNTHETIC COMMUN 2019. [DOI: 10.1080/00397911.2019.1597123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Shunsuke Nakamura
- Graduate School of Science and Engineering, Fukushima University, Fukushima, Japan
| | - Tsugiko Takase
- Institute of Environmental Radioactivity, Fukushima University, Fukushima, Japan
| | - Dai Oyama
- Department of Industrial Systems Engineering, Cluster of Science and Engineering, Fukushima University, Fukushima, Japan
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20
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McPherson JN, Hogue RW, Akogun FS, Bondì L, Luis ET, Price JR, Garden AL, Brooker S, Colbran SB. Predictable Substituent Control of Co III/II Redox Potential and Spin Crossover in Bis(dipyridylpyrrolide)cobalt Complexes. Inorg Chem 2019; 58:2218-2228. [PMID: 30672281 DOI: 10.1021/acs.inorgchem.8b03457] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A family of five easily prepared tridentate monoanionic 2,5-dipyridyl-3-(R1)-4-(R2)-pyrrolide anions (dppR1,R2)-, varying in the nature of the R1 and R2 substituents [R1, R2 = CN, Ph; CO2Et, CO2Et; CO2Me, 4-Py; CO2Me, Me; Me, Me], has been used to generate the analogous family of neutral [CoII(dppR1,R2)2] complexes, two of which are structurally characterized at both 100 and 298 K. Both the oxidation and spin states of these complexes can be switched in response to appropriate external stimuli. All complexes, except [CoII(dppMe,Me)2], exhibit gradual spin crossover (SCO) in the solid state, and SCO activity is observed for three complexes in CDCl3 solution. The cobalt(II) centers in the low spin (LS) complexes are Jahn-Teller tetragonally compressed along the pyrrolide-Co-pyrrolide axis. The complexes in their high spin (HS) states are more distorted than in the LS states, as is also usually the case for SCO active iron(II) complexes. The reversible CoIII/II redox potentials are predictably tuned by choice of substituents R1 and R2, from -0.95 (Me,Me) to -0.45 (CN,Ph) V vs Fc+/Fc, with a linear correlation observed between E1/2(CoIII/II) and the Swain-Lupton parameters of the pyrrolide substituents.
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Affiliation(s)
- James N McPherson
- School of Chemistry , The University of New South Wales , Kensington , NSW 2052 , Australia
| | - Ross W Hogue
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology , University of Otago , P.O. Box 56, Dunedin 9054 , New Zealand
| | - Folaranmi Sunday Akogun
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology , University of Otago , P.O. Box 56, Dunedin 9054 , New Zealand
| | - Luca Bondì
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology , University of Otago , P.O. Box 56, Dunedin 9054 , New Zealand
| | - Ena T Luis
- School of Chemistry , The University of New South Wales , Kensington , NSW 2052 , Australia
| | - Jason R Price
- ANSTO, Australian Synchrotron , Clayton , VIC Australia
| | - Anna L Garden
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology , University of Otago , P.O. Box 56, Dunedin 9054 , New Zealand
| | - Sally Brooker
- Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology , University of Otago , P.O. Box 56, Dunedin 9054 , New Zealand
| | - Stephen B Colbran
- School of Chemistry , The University of New South Wales , Kensington , NSW 2052 , Australia
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21
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Jiang C, Nichols AW, Machan CW. A look at periodic trends in d-block molecular electrocatalysts for CO2 reduction. Dalton Trans 2019; 48:9454-9468. [DOI: 10.1039/c9dt00491b] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Periodic trends in the electronic structure of the transition metal centers can be used to explain the observed CO2 reduction activities in molecular electrocatalysts for CO2 reductions. Research activities concerning both horizontal and vertical trends have been summarized with mononuclear complexes from Group 6 to Group 10.
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Affiliation(s)
| | - Asa W. Nichols
- Department of Chemistry
- University of Virginia
- Charlottesville
- USA
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22
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DeLuca EE, Xu Z, Lam J, Wolf MO. Improved Electrocatalytic CO2 Reduction with Palladium bis(NHC) Pincer Complexes Bearing Cationic Side Chains. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00649] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Emile E. DeLuca
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Zhen Xu
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Jasper Lam
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Michael O. Wolf
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
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23
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Liu JQ, Gou XX, Han YF. Chelating Bis(N-Heterocyclic Carbene) Palladium-Catalyzed Reactions. Chem Asian J 2018; 13:2257-2276. [DOI: 10.1002/asia.201800583] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 06/02/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Ji-Quan Liu
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry; College of Chemistry and Materials Science; Northwest University; Xi'an 710127 P.R. China
| | - Xing-Xing Gou
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry; College of Chemistry and Materials Science; Northwest University; Xi'an 710127 P.R. China
| | - Ying-Feng Han
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry; College of Chemistry and Materials Science; Northwest University; Xi'an 710127 P.R. China
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24
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Cao Z, Derrick JS, Xu J, Gao R, Gong M, Nichols EM, Smith PT, Liu X, Wen X, Copéret C, Chang CJ. Chelating N‐Heterocyclic Carbene Ligands Enable Tuning of Electrocatalytic CO
2
Reduction to Formate and Carbon Monoxide: Surface Organometallic Chemistry. Angew Chem Int Ed Engl 2018; 57:4981-4985. [DOI: 10.1002/anie.201800367] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/27/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Zhi Cao
- Department of Chemistry University of California Berkeley CA 94720 USA
| | - Jeffrey S. Derrick
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Jun Xu
- Department of Chemistry and Applied Biosciences ETH Zürich Vladimir Prelog Weg 1–5 8093 Zürich Switzerland
| | - Rui Gao
- Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China
- Synfuels China Beijing 100195 China
| | - Ming Gong
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Eva M. Nichols
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Peter T. Smith
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Xingwu Liu
- Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China
- Synfuels China Beijing 100195 China
| | - Xiaodong Wen
- Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China
- Synfuels China Beijing 100195 China
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences ETH Zürich Vladimir Prelog Weg 1–5 8093 Zürich Switzerland
| | - Christopher J. Chang
- Department of Chemistry University of California Berkeley CA 94720 USA
- Department of Molecular and Cell Biology Howard Hughes Medical Institute University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
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25
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Cao Z, Derrick JS, Xu J, Gao R, Gong M, Nichols EM, Smith PT, Liu X, Wen X, Copéret C, Chang CJ. Chelating N‐Heterocyclic Carbene Ligands Enable Tuning of Electrocatalytic CO
2
Reduction to Formate and Carbon Monoxide: Surface Organometallic Chemistry. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201800367] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Zhi Cao
- Department of Chemistry University of California Berkeley CA 94720 USA
| | - Jeffrey S. Derrick
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Jun Xu
- Department of Chemistry and Applied Biosciences ETH Zürich Vladimir Prelog Weg 1–5 8093 Zürich Switzerland
| | - Rui Gao
- Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China
- Synfuels China Beijing 100195 China
| | - Ming Gong
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Eva M. Nichols
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Peter T. Smith
- Department of Chemistry University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Xingwu Liu
- Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China
- Synfuels China Beijing 100195 China
| | - Xiaodong Wen
- Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan Shanxi 030001 China
- Synfuels China Beijing 100195 China
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences ETH Zürich Vladimir Prelog Weg 1–5 8093 Zürich Switzerland
| | - Christopher J. Chang
- Department of Chemistry University of California Berkeley CA 94720 USA
- Department of Molecular and Cell Biology Howard Hughes Medical Institute University of California Berkeley CA 94720 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
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27
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Hanson SS, Warren JJ. Syntheses, characterization, and electrochemical behavior of alkylated 2-(2′-quinolylbenzimidazole) complexes of rhenium (I). CAN J CHEM 2018. [DOI: 10.1139/cjc-2017-0320] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A series of ClRe(CO)3-containing complexes with 1-methyl-1H-benzo[d]imidazol-2-yl)quinoline (Me-QuBIm), 1-benzyl-1H-benzo[d]imidazol-2-yl)quinoline (Bn-QuBIm), and 2-(1-(4-methoxybenzyl)-1H-benzo[d]imidazol-2-yl)quinoline (OMeBn-QuBIm) ligands were prepared and characterized. Each complex was characterized using 1H and 13C NMR, infrared, UV–vis, and fluorescence spectroscopies, and cyclic voltammetry. The physical properties of each complex are similar to the parent ClRe(CO)3(2-(1H-benzo[d]imidazol-2-yl)quinoline) complex. However, the electrochemical behavior is distinct from the parent, showing reversible voltammograms and poor CO2 reduction activity. Addition of K+ or Mg2+ as Lewis acids modestly increases catalytic currents, but at large overpotentials. The work presented here is consistent with a mechanism that involves rhenium reduction and deprotonation of imidazole and benzimidazole prior to CO2 reduction electrocatalysis.
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Affiliation(s)
- Samuel S. Hanson
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Jeffrey J. Warren
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
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28
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Francke R, Schille B, Roemelt M. Homogeneously Catalyzed Electroreduction of Carbon Dioxide-Methods, Mechanisms, and Catalysts. Chem Rev 2018; 118:4631-4701. [PMID: 29319300 DOI: 10.1021/acs.chemrev.7b00459] [Citation(s) in RCA: 587] [Impact Index Per Article: 97.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The utilization of CO2 via electrochemical reduction constitutes a promising approach toward production of value-added chemicals or fuels using intermittent renewable energy sources. For this purpose, molecular electrocatalysts are frequently studied and the recent progress both in tuning of the catalytic properties and in mechanistic understanding is truly remarkable. While in earlier years research efforts were focused on complexes with rare metal centers such as Re, Ru, and Pd, the focus has recently shifted toward earth-abundant transition metals such as Mn, Fe, Co, and Ni. By application of appropriate ligands, these metals have been rendered more than competitive for CO2 reduction compared to the heavier homologues. In addition, the important roles of the second and outer coordination spheres in the catalytic processes have become apparent, and metal-ligand cooperativity has recently become a well-established tool for further tuning of the catalytic behavior. Surprising advances have also been made with very simple organocatalysts, although the mechanisms behind their reactivity are not yet entirely understood. Herein, the developments of the last three decades in electrocatalytic CO2 reduction with homogeneous catalysts are reviewed. A discussion of the underlying mechanistic principles is included along with a treatment of the experimental and computational techniques for mechanistic studies and catalyst benchmarking. Important catalyst families are discussed in detail with regard to mechanistic aspects, and recent advances in the field are highlighted.
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Affiliation(s)
- Robert Francke
- Institute of Chemistry , Rostock University , Albert-Einstein-Strasse 3a , 18059 Rostock , Germany
| | - Benjamin Schille
- Institute of Chemistry , Rostock University , Albert-Einstein-Strasse 3a , 18059 Rostock , Germany
| | - Michael Roemelt
- Lehrstuhl für Theoretische Chemie , Ruhr-University Bochum , 44780 Bochum , Germany.,Max-Planck Institut für Kohlenforschung , Kaiser-Wilhelm Platz 1 , 45470 Mülheim an der Ruhr , Germany
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29
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Gonell S, Miller AJ. Carbon Dioxide Electroreduction Catalyzed by Organometallic Complexes. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2018. [DOI: 10.1016/bs.adomc.2018.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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30
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Andrade GA, DiMeglio JL, Guardino ET, Yap GPA, Rosenthal J. Synthesis and structure of palladium(II) complexes supported by bis-NHC pincer ligands for the electrochemical activation of CO 2. Polyhedron 2017; 135:134-143. [PMID: 30983680 DOI: 10.1016/j.poly.2017.06.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A series of bis-NHC pincer complexes of palladium(II) have been prepared and characterized. These pyridyl-spaced dicarbene complexes ([(PDCR)Pd(MeCN)](PF6)2 ) were synthesized with substituents of varying steric bulk at the wingtip positions, which include R = methyl, ethyl, isopropyl, cyclohexyl, mesityl and 2,6-diisopropylphenyl. The synthesis of this library of complexes was accomplished either by direct metallation of the prerequisite pyridyl-spaced bis-imidazolium proligands with Pd(OAc)2 or via treatment with Ag2O to afford the corresponding silver carbenes, which were then transmetallated onto palladium. Solid-state structures for each of the [(PDCR)Pd(MeCN)](PF6)2 derivatives were obtained via X-ray crystallography and allowed for the steric properties of each PDCR ligand to be evaluated by two methods. These analyses, which included calculation of the percent buried volume (%VBur) and solid angles of the PDCR ligands, served to characterize the steric environment around the palladium center in each of the complexes that was prepared. Finally, voltammetry and controlled potential electrolysis studies were performed to characterize the redox chemistry of the [(PDCR)Pd(MeCN)](PF6)2 derivatives and assess if they could electrocatalyze the reduction of CO2. The influence of the steric properties of the PDCR ligand on the electrochemistry of the resulting complexes [(PDCR)Pd(MeCN)](PF6)2 is also discussed.
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Affiliation(s)
- Gabriel A Andrade
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - John L DiMeglio
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - Eric T Guardino
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - Glenn P A Yap
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - Joel Rosenthal
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States
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