1
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Garrido-Barros P, Romero CG, Winkler JR, Peters JC. Intermolecular Proton-Coupled Electron Transfer Reactivity from a Persistent Charge-Transfer State for Reductive Photoelectrocatalysis. J Am Chem Soc 2024; 146:12750-12757. [PMID: 38669102 PMCID: PMC11082884 DOI: 10.1021/jacs.4c02610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 04/05/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024]
Abstract
Interest in applying proton-coupled electron transfer (PCET) reagents in reductive electro- and photocatalysis requires strategies that mitigate the competing hydrogen evolution reaction. Photoexcitation of a PCET donor to a charge-separated state (CSS) can produce a powerful H-atom donor capable of being electrochemically recycled at a comparatively anodic potential corresponding to its ground state. However, the challenge is designing a mediator with a sufficiently long-lived excited state for bimolecular reactivity. Here, we describe a powerful ferrocene-derived photoelectrochemical PCET mediator exhibiting an unusually long-lived CSS (τ ∼ 0.9 μs). In addition to detailed photophysical studies, proof-of-concept stoichiometric and catalytic proton-coupled reductive transformations are presented, which illustrate the promise of this approach.
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Affiliation(s)
| | | | - Jay R. Winkler
- Division of Chemistry and Chemical
Engineering, California Institute of Technology
(Caltech), Pasadena, California 91125, United States
| | - Jonas C. Peters
- Division of Chemistry and Chemical
Engineering, California Institute of Technology
(Caltech), Pasadena, California 91125, United States
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2
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Huang KY, Yang ZQ, Yang MR, Chen TS, Tang S, Sun WM, Yao Q, Deng HH, Chen W, Xie J. Unraveling a Concerted Proton-Coupled Electron Transfer Pathway in Atomically Precise Gold Nanoclusters. J Am Chem Soc 2024; 146:8706-8715. [PMID: 38487838 DOI: 10.1021/jacs.4c01180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Metal nanoclusters (MNCs) represent a promising class of materials for catalytic carbon dioxide and proton reduction as well as dihydrogen oxidation. In such reactions, multiple proton-coupled electron transfer (PCET) processes are typically involved, and the current understanding of PCET mechanisms in MNCs has primarily focused on the sequential transfer mode. However, a concerted transfer pathway, i.e., concerted electron-proton transfer (CEPT), despite its potential for a higher catalytic rate and lower reaction barrier, still lacks comprehensive elucidation. Herein, we introduce an experimental paradigm to test the feasibility of the CEPT process in MNCs, by employing Au18(SR)14 (SR denotes thiolate ligand), Au22(SR)18, and Au25(SR)18- as model clusters. Detailed investigations indicate that the photoinduced PCET reactions in the designed system proceed via an CEPT pathway. Furthermore, the rate constants of gold nanoclusters (AuNCs) have been found to be correlated with both the size of the cluster and the flexibility of the Au-S framework. This newly identified PCET behavior in AuNCs is prominently different from that observed in semiconductor quantum dots and plasmonic metal nanoparticles. Our findings are of crucial importance for unveiling the catalytic mechanisms of quantum-confined metal nanomaterials and for the future rational design of more efficient catalysts.
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Affiliation(s)
- Kai-Yuan Huang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Zhi-Qiang Yang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Ming-Rui Yang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Tian-Shui Chen
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Shurong Tang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Wei-Ming Sun
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Qiaofeng Yao
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Key Laboratory of Organic Integrated Circuits, Ministry of Education, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China
| | - Hao-Hua Deng
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Wei Chen
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Jianping Xie
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117585, Singapore
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3
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Ye Y, Garrido-Barros P, Wellauer J, Cruz CM, Lescouëzec R, Wenger OS, Herrera JM, Jiménez JR. Luminescence and Excited-State Reactivity in a Heteroleptic Tricyanido Fe(III) Complex. J Am Chem Soc 2024; 146:954-960. [PMID: 38156951 PMCID: PMC10786067 DOI: 10.1021/jacs.3c11517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 01/03/2024]
Abstract
Harnessing sunlight via photosensitizing molecules is key for novel optical applications and solar-to-chemical energy conversion. Exploiting abundant metals such as iron is attractive but becomes challenging due to typically fast nonradiative relaxation processes. In this work, we report on the luminescence and excited-state reactivity of the heteroleptic [FeIII(pzTp)(CN)3]- complex (pzTp = tetrakis(pyrazolyl)borate), which incorporates a σ-donating trispyrazolyl chelate ligand and three monodentate σ-donating and π-accepting cyanide ligands. Contrary to the nonemissive [Fe(CN)6]3-, a broad emission band centered at 600 nm at room temperature has been recorded for the heteroleptic analogue attributed to the radiative deactivation from a 2LMCT excited state with a luminescence quantum yield of 0.02% and a lifetime of 80 ps in chloroform at room temperature. Bimolecular reactivity of the 2LMCT excited state was successfully applied to different alcohol photo-oxidation, identifying a cyanide-H bonding as a key reaction intermediate. Finally, this research demonstrated the exciting potential of [Fe(pzTp)(CN)3]- as a photo-oxidant, paving the way for further exploration and development of emissive Fe-based photosensitizers competent for photochemical transformations.
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Affiliation(s)
- Yating Ye
- Departamento
de Química Inorgánica, Facultad de Ciencias, Universidad de Granada and Unidad de Excelencia en
Química (UEQ), Avenida Fuente Nueva s/n, 18071, Granada, Spain
| | - Pablo Garrido-Barros
- Departamento
de Química Inorgánica, Facultad de Ciencias, Universidad de Granada and Unidad de Excelencia en
Química (UEQ), Avenida Fuente Nueva s/n, 18071, Granada, Spain
| | - Joël Wellauer
- Department
of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Carlos M. Cruz
- Departamento
de Química Orgánica, Facultad de Ciencias, Universidad de Granada and Unidad de Excelencia en
Química (UEQ), Avenida Fuente Nueva s/n, 18071, Granada, Spain
| | - Rodrigue Lescouëzec
- Institut
Parisien de Chimie Moléculaire, CNRS, UMR 8232, Sorbonne Université, F-75252 Paris Cedex
5, France
| | - Oliver S. Wenger
- Department
of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Juan Manuel Herrera
- Departamento
de Química Inorgánica, Facultad de Ciencias, Universidad de Granada and Unidad de Excelencia en
Química (UEQ), Avenida Fuente Nueva s/n, 18071, Granada, Spain
| | - Juan-Ramón Jiménez
- Departamento
de Química Inorgánica, Facultad de Ciencias, Universidad de Granada and Unidad de Excelencia en
Química (UEQ), Avenida Fuente Nueva s/n, 18071, Granada, Spain
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4
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Qiu G, Schreiner PR. The Intrinsic Barrier Width and Its Role in Chemical Reactivity. ACS CENTRAL SCIENCE 2023; 9:2129-2137. [PMID: 38033803 PMCID: PMC10683502 DOI: 10.1021/acscentsci.3c00926] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/29/2023] [Accepted: 10/12/2023] [Indexed: 12/02/2023]
Abstract
Chemical reactions are in virtually all cases understood and explained on the basis of depicting the molecular potential energy landscape, i.e., the change in atomic positions vs the free-energy change. With such landscapes, the features of the reaction barriers solely determine chemical reactivities. The Marcus dissection of the barrier height (activation energy) on such a potential into the thermodynamically independent (intrinsic) and the thermodynamically dependent (Bell-Evans-Polanyi) contributions successfully models the interplay of reaction rate and driving force. This has led to the well-known and ubiquitously used reactivity paradigm of "kinetic versus thermodynamic control". However, an analogous dissection concept regarding the barrier width is absent. Here we define and outline the concept of intrinsic barrier width and the driving force effect on the barrier width and report experimental as well as theoretical studies to demonstrate their distinct roles. We present the idea of changing the barrier widths of conformational isomerizations of some simple aromatic carboxylic acids as models and use quantum mechanical tunneling (QMT) half-lives as a read-out for these changes because QMT is particularly sensitive to barrier widths. We demonstrate the distinct roles of the intrinsic and the thermodynamic contributions of the barrier width on QMT half-lives. This sheds light on resolving conflicting trends in chemical reactivities where barrier widths are relevant and allows us to draw some important conclusions about the general relevance of barrier widths, their qualitative definition, and the consequences for more complete descriptions of chemical reactions.
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Affiliation(s)
- Guanqi Qiu
- Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Peter R. Schreiner
- Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
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5
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Teindl K, Patrick BO, Nichols EM. Linear Free Energy Relationships and Transition State Analysis of CO 2 Reduction Catalysts Bearing Second Coordination Spheres with Tunable Acidity. J Am Chem Soc 2023; 145:17176-17186. [PMID: 37499125 DOI: 10.1021/jacs.3c03919] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
In molecular catalysts, protic functional groups in the secondary coordination sphere (SCS) work in conjunction with an exogenous acid to relay protons to the active site of electrochemical CO2 reduction; however, it is not well understood how the acidity of the SCS and exogenous acid together determine the kinetics of catalytic turnover. To evaluate the relative contributions of proton transfer driving forces, we synthesized a series of modular iron tetraphenylporphyrin electrocatalysts bearing SCS amides of tunable pKa (17.6 to 20.0 in dimethyl sulfoxide (DMSO)) and employed phenols of variable acidity (15.3 to 19.1) as exogenous acids. This system allowed us to (1) evaluate contributions from proton transfer driving forces associated with either the SCS or exogenous acid and (2) obtain mechanistic insights into CO2 reduction as a function of pKa. A series of linear free-energy relationships show that kinetics become increasingly sensitive to variations in SCS pKa when more acidic exogenous acids are used (0.82 ≥ Brønsted α ≥ 0.13), as well as to variations in exogenous acid pKa when SCS acidity is increased (0.62 ≥ Brønsted α ≥ 0.32). An Eyring analysis suggests that the rate-determining transition state becomes more ordered with decreasing SCS acidity, which is consistent with the proposal that SCS acidity modulates charge accumulation and solvation at the rate-limiting transition state. Together, these insights enable the optimization of activation barriers as a function of both SCS and exogenous acid pKa and can further guide the rational design of electrocatalytic systems wherein contributions from all participants in a proton relay are considered.
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Affiliation(s)
- Kaeden Teindl
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Brian O Patrick
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Eva M Nichols
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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6
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Pattanayak S, Berben LA. Pre-Equilibrium Reaction Mechanism as a Strategy to Enhance Rate and Lower Overpotential in Electrocatalysis. J Am Chem Soc 2023; 145:3419-3426. [PMID: 36734988 PMCID: PMC9936576 DOI: 10.1021/jacs.2c10942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Pre-equilibrium reaction kinetics enable the overall rate of a catalytic reaction to be orders of magnitude faster than the rate-determining step. Herein, we demonstrate how pre-equilibrium kinetics can be applied to breaking the linear free-energy relationship (LFER) for electrocatalysis, leading to rate enhancement 5 orders of magnitude and lowering of overpotential to approximately thermoneutral. This approach is applied to pre-equilibrium formation of a metal-hydride intermediate to achieve fast formate formation rates from CO2 reduction without loss of selectivity (i.e., H2 evolution). Fast pre-equilibrium metal-hydride formation, at 108 M-1 s-1, boosts the CO2 electroreduction to formate rate up to 296 s-1. Compared with molecular catalysts that have similar overpotential, this rate is enhanced by 5 orders of magnitude. As an alternative comparison, overpotential is lowered by ∼50 mV compared to catalysts with a similar rate. The principles elucidated here to obtain pre-equilibrium reaction kinetics via catalyst design are general. Design and development that builds on these principles should be possible in both molecular homogeneous and heterogeneous electrocatalysis.
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7
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Bower JK, Reese MS, Mazin IM, Zarnitsa LM, Cypcar AD, Moore CE, Sokolov AY, Zhang S. C(sp 3)-H cyanation by a formal copper(iii) cyanide complex. Chem Sci 2023; 14:1301-1307. [PMID: 36756315 PMCID: PMC9891353 DOI: 10.1039/d2sc06573h] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/05/2023] [Indexed: 01/18/2023] Open
Abstract
High-valent metal oxo complexes are prototypical intermediates for the activation and hydroxylation of alkyl C-H bonds. Substituting the oxo ligand with other functional groups offers the opportunity for additional C-H functionalization beyond C-O bond formation. However, few species aside from metal oxo complexes have been reported to both activate and functionalize alkyl C-H bonds. We herein report the first example of an isolated copper(iii) cyanide complex (LCuIIICN) and its C-H cyanation reactivity. We found that the redox potential (E ox) of substrates, instead of C-H bond dissociation energy, is a key determinant of the rate of PCET, suggesting an oxidative asynchronous CPET or ETPT mechanism. Among substrates with the same BDEs, those with low redox potentials transfer H atoms up to a million-fold faster. Capitalizing on this mechanistic insight, we found that LCuIIICN is highly selective for cyanation of amines, which is predisposed to oxidative asynchronous or stepwise transfer of H+/e-. Our study demonstrates that the asynchronous effect of PCET is an appealing tool for controlling the selectivity of C-H functionalization.
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Affiliation(s)
- Jamey K. Bower
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Maxwell S. Reese
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Ilia M. Mazin
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Lina M. Zarnitsa
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Andrew D. Cypcar
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Curtis E. Moore
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Alexander Yu. Sokolov
- Department of Chemistry and Biochemistry, The Ohio State University100 W. 18 AveColumbusOH43210USA
| | - Shiyu Zhang
- Department of Chemistry and Biochemistry, The Ohio State University 100 W. 18th Ave Columbus OH 43210 USA
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8
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Agarwal RG, Mayer JM. Coverage-Dependent Rate-Driving Force Relationships: Hydrogen Transfer from Cerium Oxide Nanoparticle Colloids. J Am Chem Soc 2022; 144:20699-20709. [DOI: 10.1021/jacs.2c07988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Rishi G. Agarwal
- Department of Chemistry, Yale University, New Haven, Connecticut06520-8107, United States
| | - James M. Mayer
- Department of Chemistry, Yale University, New Haven, Connecticut06520-8107, United States
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9
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Dey S, Masero F, Brack E, Fontecave M, Mougel V. Electrocatalytic metal hydride generation using CPET mediators. Nature 2022; 607:499-506. [PMID: 35859199 DOI: 10.1038/s41586-022-04874-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 05/16/2022] [Indexed: 11/09/2022]
Abstract
Transition metal hydrides (M-H) are ubiquitous intermediates in a wide range of enzymatic processes and catalytic reactions, playing a central role in H+/H2 interconversion1, the reduction of CO2 to formic acid (HCOOH)2 and in hydrogenation reactions. The facile formation of M-H is a critical challenge to address to further improve the energy efficiency of these reactions. Specifically, the easy electrochemical generation of M-H using mild proton sources is key to enable high selectivity versus competitive CO and H2 formation in the CO2 electroreduction to HCOOH, the highest value-added CO2 reduction product3. Here we introduce a strategy for electrocatalytic M-H generation using concerted proton-electron transfer (CPET) mediators. As a proof of principle, the combination of a series of CPET mediators with the CO2 electroreduction catalyst [MnI(bpy)(CO)3Br] (bpy = 2,2'-bipyridine) was investigated, probing the reversal of the product selectivity from CO to HCOOH to evaluate the efficiency of the manganese hydride (Mn-H) generation step. We demonstrate the formation of the Mn-H species by in situ spectroscopic techniques and determine the thermodynamic boundary conditions for this mechanism to occur. A synthetic iron-sulfur cluster is identified as the best CPET mediator for the system, enabling the preparation of a benchmark catalytic system for HCOOH generation.
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Affiliation(s)
- Subal Dey
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Sorbonne Université, Paris, France
| | - Fabio Masero
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland
| | - Enzo Brack
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, Collège de France, Sorbonne Université, Paris, France
| | - Victor Mougel
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland.
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10
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Xie W, Wang M, Yang S, Chen Y, Feng J, Huang Y. C-H chlorination of (hetero)anilines via photo/organo co-catalysis. Org Biomol Chem 2022; 20:5319-5324. [PMID: 35730736 DOI: 10.1039/d2ob00834c] [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
Chlorinated (hetero)anilines are a class of important structural motifs that are widely present in synthetic building blocks and pharmaceuticals. Despite recent advancements, direct aniline chlorination still suffers from ortho/para and mono/poly chlorination selectivity problems. Herein, we disclose a photo-redox and organo co-catalyzed chlorination method for anilines. This method has great substrate generality and excellent mono-chlorination selectivity. Another merit of this method is the late-stage modification of drug molecules, which would be useful in medicinal chemistry.
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Affiliation(s)
- Wuchen Xie
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, No. 24 Tongjiaxiang Road, Nanjing, 210009, P. R. China.
| | - Meng Wang
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, No. 24 Tongjiaxiang Road, Nanjing, 210009, P. R. China.
| | - Siyu Yang
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, No. 24 Tongjiaxiang Road, Nanjing, 210009, P. R. China.
| | - Yadong Chen
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, No. 24 Tongjiaxiang Road, Nanjing, 210009, P. R. China.
| | - Jie Feng
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, No. 24 Tongjiaxiang Road, Nanjing, 210009, P. R. China.
| | - Yatian Huang
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, No. 24 Tongjiaxiang Road, Nanjing, 210009, P. R. China.
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11
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Koronkiewicz B, Sayfutyarova ER, Coste SC, Mercado BQ, Hammes-Schiffer S, Mayer JM. Structural and Thermodynamic Effects on the Kinetics of C-H Oxidation by Multisite Proton-Coupled Electron Transfer in Fluorenyl Benzoates. J Org Chem 2022; 87:2997-3006. [PMID: 35113555 DOI: 10.1021/acs.joc.1c02834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Our recent experimental and theoretical investigations have shown that fluorene C-H bonds can be activated through a mechanism in which the proton and electron are transferred from the C-H bond to a separate base and oxidant in a concerted, elementary step. This multisite proton-coupled electron transfer (MS-PCET) mechanism for C-H bond activation was shown to be facilitated by shorter proton donor-acceptor distances. With the goal of intentionally modulating this donor-acceptor distance, we have now studied C-H MS-PCET in the 3-methyl-substituted fluorenyl benzoate (2-Flr-3-Me-BzO-). This derivative was readily oxidized by ferrocenium oxidants by initial C-H MS-PCET, with rate constants that were 6-21 times larger than those for 2-Flr-BzO- with the same oxidants. Structural comparisons by X-ray crystallography and by computations showed that addition of the 3-methyl group caused the expected steric compression; however, the relevant C···O- proton donor-acceptor distance was longer, due to a twist of the carboxylate group. The structural changes induced by the 3-Me group increased the basicity of the carboxylate, weakened the C-H bond, and reduced the reorganization energy for C-H bond cleavage. Thus, the rate enhancement for 2-Flr-3-Me-BzO- was due to effects on the thermochemistry and kinetic barrier, rather than from compression of the C···O- proton donor-acceptor distance. These results highlight both the challenges of controlling molecules on the 0.1 Å length scale and the variety of parameters that affect PCET rate constants.
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Affiliation(s)
- Brian Koronkiewicz
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06511, United States
| | - Elvira R Sayfutyarova
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06511, United States
| | - Scott C Coste
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06511, United States
| | - Brandon Q Mercado
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06511, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06511, United States
| | - James M Mayer
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06511, United States
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12
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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: 150] [Impact Index Per Article: 75.0] [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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13
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Shen GB, Qian BC, Zhang GS, Luo GZ, Fu YH, Zhu XQ. Thermodynamics regulated organic hydride/acid pairs as novel organic hydrogen reductants. Org Chem Front 2022. [DOI: 10.1039/d2qo01605b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Organic hydride/acid pairs could realize transformation of N-substituted organic hydrides from hydride reductants to thermodynamics regulated hydrogen reductants on conveniently choosing suitable organic hydrides and acids with various acidities.
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Affiliation(s)
- Guang-Bin Shen
- School of Medical Engineering, Jining Medical University, Jining, Shandong, 272000, P. R. China
| | - Bao-Chen Qian
- School of Medical Engineering, Jining Medical University, Jining, Shandong, 272000, P. R. China
| | - Gao-Shuai Zhang
- School of Medical Engineering, Jining Medical University, Jining, Shandong, 272000, P. R. China
| | - Guang-Ze Luo
- School of Medical Engineering, Jining Medical University, Jining, Shandong, 272000, P. R. China
| | - Yan-Hua Fu
- College of Chemistry and Environmental Engineering, Anyang Institute of Technology, Anyang, Henan, 455000, China
| | - Xiao-Qing Zhu
- The State Key Laboratory of Elemento-Organic Chemistry, Department of Chemistry, Nankai University, Tianjin 300071, China
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14
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Han C, Han G, Yao S, Yuan L, Liu X, Cao Z, Mannodi‐Kanakkithodi A, Sun Y. Defective Ultrathin ZnIn 2 S 4 for Photoreductive Deuteration of Carbonyls Using D 2 O as the Deuterium Source. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2103408. [PMID: 34796666 PMCID: PMC8787392 DOI: 10.1002/advs.202103408] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/16/2021] [Indexed: 05/17/2023]
Abstract
Deuterium (D) labeling is of great value in organic synthesis, pharmaceutical industry, and materials science. However, the state-of-the-art deuteration methods generally require noble metal catalysts, expensive deuterium sources, or harsh reaction conditions. Herein, noble metal-free and ultrathin ZnIn2 S4 (ZIS) is reported as an effective photocatalyst for visible light-driven reductive deuteration of carbonyls to produce deuterated alcohols using heavy water (D2 O) as the sole deuterium source. Defective two-dimensional ZIS nanosheets (D-ZIS) are prepared in a surfactant assisted bottom-up route exhibited much enhanced performance than the pristine ZIS counterpart. A systematic study is carried out to elucidate the contributing factors and it is found that the in situ surfactant modification enabled D-ZIS to expose more defect sites for charge carrier separation and active D-species generation, as well as high specific surface area, all of which are beneficial for the desirable deuteration reaction. This work highlights the great potential in developing low-cost semiconductor-based photocatalysts for organic deuteration in D2 O, circumventing expensive deuterium reagents and harsh conditions.
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Affiliation(s)
- Chuang Han
- Department of ChemistryUniversity of CincinnatiCincinnatiOH45221USA
| | - Guanqun Han
- Department of ChemistryUniversity of CincinnatiCincinnatiOH45221USA
| | - Shukai Yao
- School of Materials EngineeringPurdue UniversityWest LafayetteIN47907USA
| | - Lan Yuan
- School of Chemistry and Chemical EngineeringWuhan University of Science and TechnologyWuhan430081China
| | - Xingwu Liu
- Syncat@BeijingSynfuels CHINA Company, Ltd.Beijing101407China
| | - Zhi Cao
- Syncat@BeijingSynfuels CHINA Company, Ltd.Beijing101407China
| | | | - Yujie Sun
- Department of ChemistryUniversity of CincinnatiCincinnatiOH45221USA
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15
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Agarwal RG, Coste SC, Groff BD, Heuer AM, Noh H, Parada GA, Wise CF, Nichols EM, Warren JJ, Mayer JM. Free Energies of Proton-Coupled Electron Transfer Reagents and Their Applications. Chem Rev 2021; 122:1-49. [PMID: 34928136 DOI: 10.1021/acs.chemrev.1c00521] [Citation(s) in RCA: 131] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We present an update and revision to our 2010 review on the topic of proton-coupled electron transfer (PCET) reagent thermochemistry. Over the past decade, the data and thermochemical formalisms presented in that review have been of value to multiple fields. Concurrently, there have been advances in the thermochemical cycles and experimental methods used to measure these values. This Review (i) summarizes those advancements, (ii) corrects systematic errors in our prior review that shifted many of the absolute values in the tabulated data, (iii) provides updated tables of thermochemical values, and (iv) discusses new conclusions and opportunities from the assembled data and associated techniques. We advocate for updated thermochemical cycles that provide greater clarity and reduce experimental barriers to the calculation and measurement of Gibbs free energies for the conversion of X to XHn in PCET reactions. In particular, we demonstrate the utility and generality of reporting potentials of hydrogenation, E°(V vs H2), in almost any solvent and how these values are connected to more widely reported bond dissociation free energies (BDFEs). The tabulated data demonstrate that E°(V vs H2) and BDFEs are generally insensitive to the nature of the solvent and, in some cases, even to the phase (gas versus solution). This Review also presents introductions to several emerging fields in PCET thermochemistry to give readers windows into the diversity of research being performed. Some of the next frontiers in this rapidly growing field are coordination-induced bond weakening, PCET in novel solvent environments, and reactions at material interfaces.
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Affiliation(s)
- Rishi G Agarwal
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Scott C Coste
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Benjamin D Groff
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Abigail M Heuer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Hyunho Noh
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Giovanny A Parada
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.,Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
| | - Catherine F Wise
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Eva M Nichols
- Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Jeffrey J Warren
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - James M Mayer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
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16
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Shaw K, Sharma S, Khatua A, Paul A, Bisai A. Oxidative electro-organic synthesis of dimeric hexahydropyrrolo-[2,3- b]indole alkaloids involving PCET: total synthesis of (±)-folicanthine. Org Biomol Chem 2021; 19:9390-9395. [PMID: 34705000 DOI: 10.1039/d1ob01463c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient electrochemical oxidation strategy for the total synthesis of a dimeric hexahydropyrrolo[2,3-b]indole alkaloid, (±)-folicanthine (1b), has been envisioned. Control experiments suggest that a PCET pathway involving stepwise electron transfer followed by proton transfer (ET-PT) was involved in the key oxidative dimerization process.
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Affiliation(s)
- Kundan Shaw
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal - 462 066, Madhya Pradesh, India.
| | - Sulekha Sharma
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal - 462 066, Madhya Pradesh, India.
| | - Arindam Khatua
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal - 462 066, Madhya Pradesh, India.
| | - Amit Paul
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal - 462 066, Madhya Pradesh, India.
| | - Alakesh Bisai
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal - 462 066, Madhya Pradesh, India. .,Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia - 741246, West Bengal, India
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17
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Fukuzumi S, Lee Y, Nam W. Deuterium kinetic isotope effects as redox mechanistic criterions. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12417] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Shunichi Fukuzumi
- Department of Chemistry and Nano Science Ewha Womans University Seoul Korea
- Faculty of Science and Engineering Meijo University Nagoya Aichi Japan
| | - Yong‐Min Lee
- Department of Chemistry and Nano Science Ewha Womans University Seoul Korea
- Research Institute for Basic Sciences Ewha Womans University Seoul Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science Ewha Womans University Seoul Korea
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18
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Coste SC, Brezny AC, Koronkiewicz B, Mayer JM. C-H oxidation in fluorenyl benzoates does not proceed through a stepwise pathway: revisiting asynchronous proton-coupled electron transfer. Chem Sci 2021; 12:13127-13136. [PMID: 34745543 PMCID: PMC8513817 DOI: 10.1039/d1sc03344a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/09/2021] [Indexed: 11/21/2022] Open
Abstract
2-Fluorenyl benzoates were recently shown to undergo C–H bond oxidation through intramolecular proton transfer coupled with electron transfer to an external oxidant. Kinetic analysis revealed unusual rate-driving force relationships. Our analysis indicated a mechanism of multi-site concerted proton–electron transfer (MS-CPET) for all of these reactions. More recently, an alternative interpretation of the kinetic data was proposed to explain the unusual rate-driving force relationships, invoking a crossover from CPET to a stepwise mechanism with an initial intramolecular proton transfer (PT) (Costentin, Savéant, Chem. Sci., 2020, 11, 1006). Here, we show that this proposed alternative pathway is untenable based on prior and new experimental assessments of the intramolecular PT equilibrium constant and rates. Measurement of the fluorenyl 9-C–H pKa, H/D exchange experiments, and kinetic modelling with COPASI eliminate the possibility of a stepwise mechanism for C–H oxidation in the fluorenyl benzoate series. Implications for asynchronous (imbalanced) MS-CPET mechanisms are discussed with respect to classical Marcus theory and the quantum-mechanical treatment of concerted proton–electron transfer. 2-Fluorenyl benzoates were recently shown to undergo C–H bond oxidation through intramolecular proton transfer coupled with electron transfer to an external oxidant.![]()
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Affiliation(s)
- Scott C Coste
- Department of Chemistry, Yale University New Haven CT 06520-8107 USA
| | - Anna C Brezny
- Department of Chemistry, Skidmore College Saratoga Springs New York 12866 USA
| | | | - James M Mayer
- Department of Chemistry, Yale University New Haven CT 06520-8107 USA
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19
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Siewert I, Fokin I, Kuessner KT. Transition Metal Complex Catalyzed Photo- and Electrochemical (De)hydrogenations Involving C=O and C=N Bonds. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/a-1645-3254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
AbstractHerein, we summarize the photo- and electrochemical protocols for dehydrogenation and hydrogenations involving carbonyl and imine functions. The three basic principles that have been explored to interconvert such moieties with transition metal complexes are discussed in detail and the substrate scope is evaluated. Furthermore, we describe some general thermodynamic and kinetic aspects of such electro- and photochemically driven reactions.1 Introduction2 Dehydrogenation Reactions2.1 Electrochemical Dehydrogenations Using High-Valent Metal Species2.2 Electrochemical Dehydrogenations Involving Metal Hydride species2.3 Photochemically Driven Dehydrogenation3 Hydrogenation Reactions3.1 Electrochemical Protocols3.2 Photochemical Protocols4 Conclusion5 Abbreviations
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Affiliation(s)
- Inke Siewert
- Institut für Anorganische Chemie, Universität Göttingen
- International Center for Advanced Energy Studies, Universität Göttingen
| | - Igor Fokin
- Institut für Anorganische Chemie, Universität Göttingen
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20
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Salamone M, Galeotti M, Romero-Montalvo E, van Santen JA, Groff BD, Mayer JM, DiLabio GA, Bietti M. Bimodal Evans-Polanyi Relationships in Hydrogen Atom Transfer from C(sp 3)-H Bonds to the Cumyloxyl Radical. A Combined Time-Resolved Kinetic and Computational Study. J Am Chem Soc 2021; 143:11759-11776. [PMID: 34309387 PMCID: PMC8343544 DOI: 10.1021/jacs.1c05566] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Indexed: 12/11/2022]
Abstract
The applicability of the Evans-Polanyi (EP) relationship to HAT reactions from C(sp3)-H bonds to the cumyloxyl radical (CumO•) has been investigated. A consistent set of rate constants, kH, for HAT from the C-H bonds of 56 substrates to CumO•, spanning a range of more than 4 orders of magnitude, has been measured under identical experimental conditions. A corresponding set of consistent gas-phase C-H bond dissociation enthalpies (BDEs) spanning 27 kcal mol-1 has been calculated using the (RO)CBS-QB3 method. The log kH' vs C-H BDE plot shows two distinct EP relationships, one for substrates bearing benzylic and allylic C-H bonds (unsaturated group) and the other one, with a steeper slope, for saturated hydrocarbons, alcohols, ethers, diols, amines, and carbamates (saturated group), in line with the bimodal behavior observed previously in theoretical studies of reactions promoted by other HAT reagents. The parallel use of BDFEs instead of BDEs allows the transformation of this correlation into a linear free energy relationship, analyzed within the framework of the Marcus theory. The ΔG⧧HAT vs ΔG°HAT plot shows again distinct behaviors for the two groups. A good fit to the Marcus equation is observed only for the saturated group, with λ = 58 kcal mol-1, indicating that with the unsaturated group λ must increase with increasing driving force. Taken together these results provide a qualitative connection between Bernasconi's principle of nonperfect synchronization and Marcus theory and suggest that the observed bimodal behavior is a general feature in the reactions of oxygen-based HAT reagents with C(sp3)-H donors.
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Affiliation(s)
- Michela Salamone
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica, 1, I-00133 Rome, Italy
| | - Marco Galeotti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica, 1, I-00133 Rome, Italy
| | - Eduardo Romero-Montalvo
- Department
of Chemistry, The University of British
Columbia, 3247 University Way, Kelowna, British Columbia, Canada, V1V 1V7
| | - Jeffrey A. van Santen
- Department
of Chemistry, The University of British
Columbia, 3247 University Way, Kelowna, British Columbia, Canada, V1V 1V7
| | - Benjamin D. Groff
- Department
of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - James M. Mayer
- Department
of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Gino A. DiLabio
- Department
of Chemistry, The University of British
Columbia, 3247 University Way, Kelowna, British Columbia, Canada, V1V 1V7
| | - Massimo Bietti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica, 1, I-00133 Rome, Italy
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21
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Derosa J, Garrido-Barros P, Peters JC. Electrocatalytic Reduction of C-C π-Bonds via a Cobaltocene-Derived Concerted Proton-Electron Transfer Mediator: Fumarate Hydrogenation as a Model Study. J Am Chem Soc 2021; 143:9303-9307. [PMID: 34138550 DOI: 10.1021/jacs.1c03335] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reductive concerted proton-electron transfer (CPET) is poorly developed for the reduction of C-C π-bonds, including for activated alkenes that can succumb to deleterious pathways (e.g., a competing hydrogen evolution reaction or oligomerization) in a standard electrochemical reduction. We demonstrate herein that selective hydrogenation of the C-C π-bond of fumarate esters can be achieved via electrocatalytic CPET (eCPET) using a CPET mediator comprising cobaltocene with a tethered Brønsted base. High selectivity for electrocatalytic hydrogenation is observed only when the mediator is present. Mechanistic analysis sheds light on two distinct kinetic regimes based on the substrate concentration: low fumarate concentrations operate via rate-limiting CPET followed by an electron-transfer/proton-transfer (ET/PT) step, whereas high concentrations operate via CPET followed by a rate-limiting ET/PT step.
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Affiliation(s)
- Joseph Derosa
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
| | - Pablo Garrido-Barros
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
| | - Jonas C Peters
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
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22
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Liu Z, Zhong S, Ji X, Deng GJ, Huang H. Hydroarylation of Activated Alkenes Enabled by Proton-Coupled Electron Transfer. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00649] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Zhaosheng Liu
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Shuai Zhong
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Xiaochen Ji
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Guo-Jun Deng
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Huawen Huang
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
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23
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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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24
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Zhong S, Deng GJ, Dai Z, Huang H. Visible-light-induced 4CzIPN/LiBr system: a tireless electron shuttle to enable reductive deoxygenation of N-heteroaryl carbonyls. Org Chem Front 2021. [DOI: 10.1039/d1qo00634g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A mild visible-light-induced photoredox system was found to be a tireless electron shuttle to enable reductive deoxygenation of N-heteroaryl carbonyls.
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Affiliation(s)
- Shuai Zhong
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province
- Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education
- College of Chemistry
- Xiangtan University
- Xiangtan 411105
| | - Guo-Jun Deng
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province
- Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education
- College of Chemistry
- Xiangtan University
- Xiangtan 411105
| | - Zhiqi Dai
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province
- Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education
- College of Chemistry
- Xiangtan University
- Xiangtan 411105
| | - Huawen Huang
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province
- Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education
- College of Chemistry
- Xiangtan University
- Xiangtan 411105
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25
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Affiliation(s)
- Shunichi Fukuzumi
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 South Korea
- Faculty of Science and Engineering Meijo University Nagoya Aichi 468‐0073 Japan
| | - Yong‐Min Lee
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 South Korea
- Research Institute for Basic Sciences Ewha Womans University Seoul 03760 South Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science Ewha Womans University Seoul 03760 South Korea
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26
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Sharma S, Roy A, Shaw K, Bisai A, Paul A. Electrochemical Synthesis of Dimeric 2-Oxindole Sharing Vicinal Quaternary Centers Employing Proton-Coupled Electron Transfer. J Org Chem 2020; 85:14926-14936. [DOI: 10.1021/acs.joc.0c01621] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Sulekha Sharma
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462 066, India
| | - Avishek Roy
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462 066, India
| | - Kundan Shaw
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462 066, India
| | - Alakesh Bisai
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462 066, India
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal 741 246, India
| | - Amit Paul
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh 462 066, India
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27
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Yang G, Chen K, Jin X, Yang D. Photo‐excited intramolecular charge transfer and excited state intramolecular proton transfer behaviors for
HPIBT
system: A theoretical investigation. J CHIN CHEM SOC-TAIP 2020. [DOI: 10.1002/jccs.202000121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Guang Yang
- Basic Teaching Department Jiaozuo University Jiaozuo People's Republic of China
| | - Kaifeng Chen
- Basic Teaching Department Jiaozuo University Jiaozuo People's Republic of China
| | - Xiaofeng Jin
- Basic Teaching Department Jiaozuo University Jiaozuo People's Republic of China
| | - Dapeng Yang
- Group 1101, State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences Dalian People's Republic of China
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28
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Mayfield JR, Grotemeyer EN, Jackson TA. Concerted proton-electron transfer reactions of manganese-hydroxo and manganese-oxo complexes. Chem Commun (Camb) 2020; 56:9238-9255. [PMID: 32578605 PMCID: PMC7429365 DOI: 10.1039/d0cc01201g] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The enzymes manganese superoxide dismutase and manganese lipoxygenase use MnIII-hydroxo centres to mediate proton-coupled electron transfer (PCET) reactions with substrate. As manganese is earth-abundant and inexpensive, manganese catalysts are of interest for synthetic applications. Recent years have seen exciting reports of enantioselective C-H bond oxidation by Mn catalysts supported by aminopyridyl ligands. Such catalysts offer economic and environmentally-friendly alternatives to conventional reagents and catalysts. Mechanistic studies of synthetic catalysts highlight the role of Mn-oxo motifs in attacking substrate C-H bonds, presumably by a concerted proton-electron transfer (CPET) step. (CPET is a sub-class of PCET, where the proton and electron are transferred in the same step.) Knowledge of geometric and electronic influences for CPET reactions of Mn-hydroxo and Mn-oxo adducts enhances our understanding of biological and synthetic manganese centers and informs the design of new catalysts. In this Feature article, we describe kinetic, spectroscopic, and computational studies of MnIII-hydroxo and MnIV-oxo complexes that provide insight into the basis for the CPET reactivity of these species. Systematic perturbations of the ligand environment around MnIII-hydroxo and MnIV-oxo motifs permit elucidation of structure-activity relationships. For MnIII-hydroxo centers, electron-deficient ligands enhance oxidative reactivity. However, ligand perturbations have competing consequences, as changes in the MnIII/II potential, which represents the electron-transfer component for CPET, is offset by compensating changes in the pKa of the MnII-aqua product, which represents the proton-transfer component for CPET. For MnIV-oxo systems, a multi-state reactivity model inspired the development of significantly more reactive complexes. Weakened equatorial donation to the MnIV-oxo unit results in large rate enhancements for C-H bond oxidation and oxygen-atom transfer reactions. These results demonstrate that the local coordination environment can be rationally changed to enhance reactivity of MnIII-hydroxo and MnIV-oxo adducts.
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Affiliation(s)
- Jaycee R Mayfield
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, University of Kansas, Lawrence, KS 66045, USA.
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29
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Chalkley MJ, Garrido-Barros P, Peters JC. A molecular mediator for reductive concerted proton-electron transfers
via electrocatalysis. Science 2020; 369:850-854. [DOI: 10.1126/science.abc1607] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/24/2020] [Indexed: 12/16/2022]
Abstract
Electrocatalytic approaches to the activation of unsaturated substrates
via reductive concerted proton-electron transfer (CPET) must overcome
competing, often kinetically dominant hydrogen evolution. We introduce the
design of a molecular mediator for electrochemically triggered reductive
CPET through the synthetic integration of a Brønsted acid and a redox
mediator. Cathodic reduction at the cobaltocenium redox mediator
substantially weakens the homolytic nitrogen-hydrogen bond strength of a
Brønsted acidic anilinium tethered to one of the cyclopentadienyl rings. The
electrochemically generated molecular mediator is demonstrated to transform
a model substrate, acetophenone, to its corresponding neutral α-radical via
a rate-determining CPET.
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Affiliation(s)
- Matthew J. Chalkley
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Pablo Garrido-Barros
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Jonas C. Peters
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
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30
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Glaser F, Kerzig C, Wenger OS. Multiphotonen‐Anregung in der Photoredoxkatalyse: Konzepte, Anwendungen und Methoden. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915762] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Felix Glaser
- Departement Chemie Universität Basel St. Johanns-Ring 19 4056 Basel Schweiz
| | - Christoph Kerzig
- Departement Chemie Universität Basel St. Johanns-Ring 19 4056 Basel Schweiz
| | - Oliver S. Wenger
- Departement Chemie Universität Basel St. Johanns-Ring 19 4056 Basel Schweiz
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31
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Glaser F, Kerzig C, Wenger OS. Multi-Photon Excitation in Photoredox Catalysis: Concepts, Applications, Methods. Angew Chem Int Ed Engl 2020; 59:10266-10284. [PMID: 31945241 DOI: 10.1002/anie.201915762] [Citation(s) in RCA: 183] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/16/2020] [Indexed: 01/28/2023]
Abstract
The energy of visible photons and the accessible redox potentials of common photocatalysts set thermodynamic limits to photochemical reactions that can be driven by traditional visible-light irradiation. UV excitation can be damaging and induce side reactions, hence visible or even near-IR light is usually preferable. Thus, photochemistry currently faces two divergent challenges, namely the desire to perform ever more thermodynamically demanding reactions with increasingly lower photon energies. The pooling of two low-energy photons can address both challenges simultaneously, and whilst multi-photon spectroscopy is well established, synthetic photoredox chemistry has only recently started to exploit multi-photon processes on the preparative scale. Herein, we have a critical look at currently developed reactions and mechanistic concepts, discuss pertinent experimental methods, and provide an outlook into possible future developments of this rapidly emerging area.
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Affiliation(s)
- Felix Glaser
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Christoph Kerzig
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
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32
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Karković Marković A, Jakobušić Brala C, Pilepić V, Uršić S. Kinetic Isotope Effects and Hydrogen Tunnelling in PCET Oxidations of Ascorbate: New Insights into Aqueous Chemistry? Molecules 2020; 25:molecules25061443. [PMID: 32210039 PMCID: PMC7144389 DOI: 10.3390/molecules25061443] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/19/2020] [Accepted: 03/21/2020] [Indexed: 01/12/2023] Open
Abstract
Recent experimental studies of kinetic isotope effects (KIE-s) and hydrogen tunnelling comprising three proton-coupled electron transfer (PCET) oxidations of ascorbate monoanion, (a) in aqueous reaction solutions, (b) in the mixed water-organic cosolvent systems, (c) in aqueous solutions of various salts and (d) in fairly diluted aqueous solutions of the various partial hydrophobes are reviewed. A number of new insights into the wealth of the kinetic isotope phenomena in the PCET reactions have been obtained. The modulation of KIE-s and hydrogen tunnelling observed when partially hydrophobic solutes are added into water reaction solution, in the case of fairly diluted solutions is revealed as the strong linear correlation of the isotopic ratios of the Arrhenius prefactors Ah/Ad and the isotopic differences in activation energies ΔEa (D,H). The observation has been proposed to be a signature of the involvement of the collective intermolecular excitonic vibrational dynamics of water in activation processes and aqueous chemistry.
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Affiliation(s)
| | | | | | - Stanko Uršić
- Correspondence: (C.J.B.); (S.U.); Tel.: +385-01-4870-267 (C.J.B.)
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33
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Wang P, Wang S, Zhang W, Li X, Gu Z, Li W, Zhao S, Fu Y. Preparation of MOF catalysts and simultaneously modulated metal nodes and ligands via a one-pot method for optimizing cycloaddition reactions. NEW J CHEM 2020. [DOI: 10.1039/d0nj01086c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
MOFs were adjusted with metal nodes and ligands to endow them with Lewis acids and Brønsted acids for enhanced cycloaddition reactions.
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Affiliation(s)
- Peng Wang
- College of Science
- Northeastern University
- Shenyang 100819
- China
| | - Sha Wang
- College of Science
- Northeastern University
- Shenyang 100819
- China
| | - Wenlei Zhang
- College of Science
- Northeastern University
- Shenyang 100819
- China
| | - Xiaohan Li
- College of Science
- Northeastern University
- Shenyang 100819
- China
| | - Zhida Gu
- College of Science
- Northeastern University
- Shenyang 100819
- China
| | - Wenze Li
- Department of Applied Chemistry
- Shenyang University of Chemical Technology
- Shenyang 110142
- China
| | - Shuang Zhao
- College of Science
- Northeastern University
- Shenyang 100819
- China
| | - Yu Fu
- College of Science
- Northeastern University
- Shenyang 100819
- China
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34
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Fukuzumi S, Cho KB, Lee YM, Hong S, Nam W. Mechanistic dichotomies in redox reactions of mononuclear metal–oxygen intermediates. Chem Soc Rev 2020; 49:8988-9027. [DOI: 10.1039/d0cs01251c] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review article focuses on various mechanistic dichotomies in redox reactions of metal–oxygen intermediates with the emphasis on understanding and controlling their redox reactivity from experimental and theoretical points of view.
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Affiliation(s)
- Shunichi Fukuzumi
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
- Graduate School of Science and Engineering
| | - Kyung-Bin Cho
- Department of Chemistry
- Jeonbuk National University
- Jeonju 54896
- Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
| | - Seungwoo Hong
- Department of Chemistry
- Sookmyung Women's University
- Seoul 04310
- Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science
- Ewha Womans University
- Seoul 03760
- Korea
- School of Chemistry and Chemical Engineering
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35
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Costentin C, Savéant JM. Hydrogen and proton exchange at carbon. Imbalanced transition state and mechanism crossover. Chem Sci 2019; 11:1006-1010. [PMID: 34084355 PMCID: PMC8146334 DOI: 10.1039/c9sc05147c] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
A recent remarkable study of the C-H oxidation of substituted fluorenyl-benzoates together with the transfer of a proton to an internal receiving group by means of electron transfer outer-sphere oxidants, in the noteworthy absence of hydrogen-bonding interactions, is taken as an example to uncover the existence of a mechanism crossover, making the reaction pass from a CPET pathway to a PTET pathway as the driving force of the global reaction decreases. This was also the occasion to stress that considerations based on "imbalanced" or "asynchronous" transition states cannot replace activation/driving force models based on the quantum mechanical treatment of both electrons and transferring protons.
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Affiliation(s)
- Cyrille Costentin
- Département de Chimie Moléculaire, Université Grenoble-Alpes, CNRS, UMR 5250 38000 Grenoble France .,Université Paris Diderot, Sorbonne Paris Cité 75205 Paris Cedex 13 France
| | - Jean-Michel Savéant
- Université Paris Diderot, Sorbonne Paris Cité, Laboratoire d'Electrochimie Moléculaire, Unité Mixte de Recherche Université - CNRS No. 7591 Bâtiment Lavoisier, 15 rue Jean de Baïf 75205 Paris Cedex 13 France
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36
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Wang Z, Liu Q, Ji X, Deng GJ, Huang H. Bromide-Promoted Visible-Light-Induced Reductive Minisci Reaction with Aldehydes. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04411] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Zhongzhen Wang
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Qiong Liu
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Xiaochen Ji
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Guo-Jun Deng
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
| | - Huawen Huang
- Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
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37
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Liu T, Tyburski R, Wang S, Fernández-Terán R, Ott S, Hammarström L. Elucidating Proton-Coupled Electron Transfer Mechanisms of Metal Hydrides with Free Energy- and Pressure-Dependent Kinetics. J Am Chem Soc 2019; 141:17245-17259. [PMID: 31587555 DOI: 10.1021/jacs.9b08189] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Proton-coupled electron transfer (PCET) was studied in a series of tungsten hydride complexes with pendant pyridyl arms ([(PyCH2Cp)WH(CO)3], PyCH2Cp = pyridylmethylcyclopentadienyl), triggered by laser flash-generated RuIII-tris-bipyridine oxidants, in acetonitrile solution. The free energy dependence of the rate constant and the kinetic isotope effects (KIEs) showed that the PCET mechanism could be switched between concerted and the two stepwise PCET mechanisms (electron-first or proton-first) in a predictable fashion. Straightforward and general guidelines for how the relative rates of the different mechanisms depend on oxidant and base are presented. The rate of the concerted reaction should depend symmetrically on changes in oxidant and base strength, that is on the overall ΔG0PCET, and we argue that an "asynchronous" behavior would not be consistent with a model where the electron and proton tunnel from a common transition state. The observed rate constants and KIEs were examined as a function of hydrostatic pressure (1-2000 bar) and were found to exhibit qualitatively different dependence on pressure for different PCET mechanisms. This is discussed in terms of different volume profiles of the PCET mechanisms as well as enhanced proton tunneling for the concerted mechanism. The results allowed for assignment of the main mechanism operating in the different cases, which is one of the critical questions in PCET research. They also show how the rate of a PCET reaction will be affected very differently by changes of oxidant and base strength, depending on which mechanism dominates. This is of fundamental interest as well as of practical importance for rational design of, for example, catalysts for fuel cells and solar fuel formation, which operate in steps of PCET reactions. The mechanistic richness shown by this system illustrates that the specific mechanism is not intrinsic to a specific synthetic catalyst or enzyme active site but depends on the reaction conditions.
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Affiliation(s)
- Tianfei Liu
- Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, SE-751 20 Uppsala , Sweden
| | - Robin Tyburski
- Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, SE-751 20 Uppsala , Sweden
| | - Shihuai Wang
- Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, SE-751 20 Uppsala , Sweden
| | - Ricardo Fernández-Terán
- Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, SE-751 20 Uppsala , Sweden
| | - Sascha Ott
- Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, SE-751 20 Uppsala , Sweden
| | - Leif Hammarström
- Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, SE-751 20 Uppsala , Sweden
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38
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Visible-light-mediated external-reductant-free reductive cross coupling of benzylammonium salts with (hetero)aryl nitriles. Sci China Chem 2019. [DOI: 10.1007/s11426-019-9597-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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39
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Qiu G, Knowles RR. Understanding Chemoselectivity in Proton-Coupled Electron Transfer: A Kinetic Study of Amide and Thiol Activation. J Am Chem Soc 2019; 141:16574-16578. [PMID: 31573194 DOI: 10.1021/jacs.9b08398] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
While the mechanistic understanding of proton-coupled electron transfer (PCET) has advanced significantly, few reports have sought to elucidate the factors that control chemoselectivity in these reactions. Here we present a kinetic study that provides a quantitative basis for understanding the chemoselectivity in competitive PCET activations of amides and thiols relevant to catalytic olefin hydroamidation reactions. These results demonstrate how the interplay between PCET rate constants, hydrogen-bonding equilibria, and rate-driving force relationships jointly determine PCET chemoselectivity under a given set of conditions. In turn, these findings predict reactivity trends in a model hydroamidation reaction, rationalize the selective activation of amide N-H bonds in the presence of much weaker thiol S-H bonds, and deliver strategies to improve the efficiencies of PCET reactions employing thiol co-catalysts.
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Affiliation(s)
- 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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40
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Dong J, Wang Z, Wang X, Song H, Liu Y, Wang Q. Ketones and aldehydes as alkyl radical equivalents for C─H functionalization of heteroarenes. SCIENCE ADVANCES 2019; 5:eaax9955. [PMID: 31646180 PMCID: PMC6788867 DOI: 10.1126/sciadv.aax9955] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 09/18/2019] [Indexed: 05/24/2023]
Abstract
The polar nature of the C═O bond commonly allows it to undergo direct attack by nucleophiles at the electrophilic carbon atom in which ketones and aldehydes act as alkyl carbocation equivalents. In contrast, transformations in which ketones and aldehydes act as alkyl radical equivalents (generated in carbonyl carbon) are unknown. Here, we describe a new catalytic activation mode that combines proton-coupled electron transfer (PCET) with spin-center shift (SCS) and enables C─H alkylation of heteroarenes using ketones and aldehydes as alkyl radical equivalents. This transformation proceeded via reductive PCET activation of the ketones and aldehydes to form α-oxy radicals, addition of the radicals to the N-heteroarenes to form C─C bonds, and SCS to cleave the C─O bonds of the resulting alcohols. This mild protocol represents a general use of abundant, commercially available, ketones and aldehydes as latent alkyl radical equivalents.
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Affiliation(s)
- Jianyang Dong
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
| | - Zhen Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
| | - Xiaochen Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
| | - Hongjian Song
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
| | - Yuxiu Liu
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
| | - Qingmin Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, People’s Republic of China
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41
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Sayfutyarova ER, Lam YC, Hammes-Schiffer S. Strategies for Enhancing the Rate Constant of C-H Bond Cleavage by Concerted Proton-Coupled Electron Transfer. J Am Chem Soc 2019; 141:15183-15189. [PMID: 31464122 DOI: 10.1021/jacs.9b06849] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recently selective C-H bond cleavage under mild conditions with weak oxidants was reported for fluorenyl-benzoates. This mechanism is based on multi-site concerted proton-coupled electron transfer (PCET) involving intermolecular electron transfer to an outer-sphere oxidant coupled to intramolecular proton transfer to a well-positioned proton acceptor. The electron transfer driving force depends predominantly on the oxidant, and the proton transfer driving force depends mainly on the basicity of the carboxylate, which is influenced by the substituent on the benzoate fragment. Experiments showed that the rate constants are much more sensitive to the carboxylate basicity than to the redox potential of the oxidant. Herein a vibronically nonadiabatic PCET theory is used to explain how changing the driving force for the electron and proton transfer components of the reaction through varying the oxidant and the substituent, respectively, impacts the PCET rate constant. In addition to increasing the driving force for proton transfer, enhancing the basicity of the carboxylate also decreases the equilibrium proton donor-acceptor distance, thereby facilitating the sampling of shorter proton donor-acceptor distances. This additional effect arising from the strong dependence of proton transfer on the proton donor-acceptor distance provides an explanation for the greater sensitivity of the rate constant to the carboxylate basicity than to the redox potential of the oxidant. These fundamental insights have broad implications for developing new strategies to activate C-H bonds, specifically by designing systems with shorter equilibrium proton donor-acceptor distances.
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Affiliation(s)
- Elvira R Sayfutyarova
- Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520 , United States
| | - Yan-Choi Lam
- Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520 , United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520 , United States
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42
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Caron A, Morin É, Collins SK. Bifunctional Copper-Based Photocatalyst for Reductive Pinacol-Type Couplings. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01718] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Antoine Caron
- Département de Chimie, Centre for Green Chemistry and Catalysis, Université de Montréal, 6128 Station Downtown, Montréal, Québec H3C 3J7, Canada
| | - Émilie Morin
- Département de Chimie, Centre for Green Chemistry and Catalysis, Université de Montréal, 6128 Station Downtown, Montréal, Québec H3C 3J7, Canada
| | - Shawn K. Collins
- Département de Chimie, Centre for Green Chemistry and Catalysis, Université de Montréal, 6128 Station Downtown, Montréal, Québec H3C 3J7, Canada
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43
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Rothermel K, Melikian M, Hioe J, Greindl J, Gramüller J, Žabka M, Sorgenfrei N, Hausler T, Morana F, Gschwind RM. Internal acidity scale and reactivity evaluation of chiral phosphoric acids with different 3,3'-substituents in Brønsted acid catalysis. Chem Sci 2019; 10:10025-10034. [PMID: 32015815 PMCID: PMC6977555 DOI: 10.1039/c9sc02342a] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 09/02/2019] [Indexed: 12/16/2022] Open
Abstract
NMR H-bond analysis reveals an offset of internal and external acidities of catalysts and allows for a detailed reactivity analysis.
The concept of hydrogen bonding for enhancing substrate binding and controlling selectivity and reactivity is central in catalysis. However, the properties of these key hydrogen bonds and their catalyst-dependent variations are extremely difficult to determine directly by experiments. Here, for the first time the hydrogen bond properties of a whole series of BINOL-derived chiral phosphoric acid (CPA) catalysts in their substrate complexes with various imines were investigated to derive the influence of different 3,3′-substituents on the acidity and reactivity. NMR 1H and 15N chemical shifts and 1JNH coupling constants of these hydrogen bonds were used to establish an internal acidity scale corroborated by calculations. Deviations from calculated external acidities reveal the importance of intermolecular interactions for this key feature of CPAs. For CPAs with similarly sized binding pockets, a correlation of reactivity and hydrogen bond strengths of the catalyst was found. A catalyst with a very small binding pocket showed significantly reduced reactivities. Therefore, NMR isomerization kinetics, population and chemical shift analyses of binary and ternary complexes as well as reaction kinetics were performed to address the steps of the transfer hydrogenation influencing the overall reaction rate. The results of CPAs with different 3,3′-substituents show a delicate balance between the isomerization and the ternary complex formation to be rate-determining. For CPAs with an identical acidic motif and similar sterics, reactivity and internal acidity correlated inversely. In cases where higher sterical demand within the binary complex hinders the binding of the second substrate, the correlation between acidity and reactivity breaks down.
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Affiliation(s)
- Kerstin Rothermel
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Maxime Melikian
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Johnny Hioe
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Julian Greindl
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Johannes Gramüller
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Matej Žabka
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Nils Sorgenfrei
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Thomas Hausler
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Fabio Morana
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
| | - Ruth M Gschwind
- Institut für Organische Chemie , Universität Regensburg , Universitätsstraße 31 , D-93053 Regensburg , Germany .
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44
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Gu C, Nie X, Jiang J, Chen Z, Dong Y, Zhang X, Liu J, Yu Z, Zhu Z, Liu J, Liu X, Shao Y. Mechanistic Study of Oxygen Reduction at Liquid/Liquid Interfaces by Hybrid Ultramicroelectrodes and Mass Spectrometry. J Am Chem Soc 2019; 141:13212-13221. [PMID: 31353892 DOI: 10.1021/jacs.9b06299] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Proton-coupled electron transfer (PCET) reactions at various interfaces (liquid/membrane, solid/electrolyte, liquid/liquid) lie at the heart of many processes in biology and chemistry. Mechanistic study can provide profound understanding of PCET and rational design of new systems. However, most mechanisms of PCET reactions at a liquid/liquid interface have been proposed based on electrochemical and spectroscopic data, which lack direct evidence for possible intermediates. Moreover, a liquid/liquid interface as one type of soft interface is dynamic, making the investigation of interfacial reactions very challenging. Herein a novel electrochemistry method coupled to mass spectrometry (EC-MS) was introduced for in situ study of the oxygen reduction reaction (ORR) by ferrocene (Fc) under catalysis from cobalt tetraphenylporphine (CoTPP) at liquid/liquid interfaces. The key units are two types of gel hybrid ultramicroelectrodes (agar-gel/organic hybrid ultramicroelectrodes and water/PVC-gel hybrid ultramicroelectrodes), which were made based on dual micro- or nanopipettes. A solidified liquid/liquid interface can be formed at the tip of these pipettes, and it serves as both an electrochemical cell and a nanospray emitter for mass spectrometry. We demonstrated that the solidified L/L interfaces were very similar to typical L/L interfaces. Key CoTPP intermediates of the ORR at the liquid/liquid interfaces were identified for the first time, and the four-electron oxygen reduction pathway predominated, which provides valuable insights into the mechanism of the ORR. Theoretical simulation has further supported the possibility of formation of intermediates. This type of platform is promising for in situ tracking and identifying intermediates to study complicated reactions at liquid/liquid interfaces or other soft interfaces.
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Affiliation(s)
- Chaoyue Gu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Xin Nie
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Jiezhang Jiang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Zifei Chen
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Yifan Dong
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Xin Zhang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Junjie Liu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Zhengyou Yu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Zhiwei Zhu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Jian Liu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Xiaoyun Liu
- Department of Microbiology, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Yuanhua Shao
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
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45
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Darcy JW, Kolmar SS, Mayer JM. Transition State Asymmetry in C-H Bond Cleavage by Proton-Coupled Electron Transfer. J Am Chem Soc 2019; 141:10777-10787. [PMID: 31199137 DOI: 10.1021/jacs.9b04303] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The selective transformation of C-H bonds is a longstanding challenge in modern chemistry. A recent report details C-H oxidation via multiple-site concerted proton-electron transfer (MS-CPET), where the proton and electron in the C-H bond are transferred to separate sites. Reactivity at a specific C-H bond was achieved by appropriate positioning of an internal benzoate base. Here, we extend that report to reactions of a series of molecules with differently substituted fluorenyl-benzoates and varying outer-sphere oxidants. These results probe the fundamental rate versus driving force relationships in this MS-CPET reaction at carbon by separately modulating the driving force for the proton and electron transfer components. The rate constants depend strongly on the pKa of the internal base, but depend much less on the nature of the outer-sphere oxidant. These observations suggest that the transition states for these reactions are imbalanced. Density functional theory (DFT) was used to generate an internal reaction coordinate, which qualitatively reproduced the experimental observation of a transition state imbalance. Thus, in this system, homolytic C-H bond cleavage involves concerted but asynchronous transfer of the H+ and e-. The nature of this transfer has implications for synthetic methodology and biological systems.
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Affiliation(s)
- Julia W Darcy
- Department of Chemistry , Yale University , New Haven , Connecticut 06520-8107 , United States
| | - Scott S Kolmar
- 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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46
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Saura P, Frey DM, Gamiz-Hernandez AP, Kaila VRI. Electric field modulated redox-driven protonation and hydration energetics in energy converting enzymes. Chem Commun (Camb) 2019; 55:6078-6081. [PMID: 31066378 PMCID: PMC6932871 DOI: 10.1039/c9cc01135h] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Biological energy conversion is catalysed by proton-coupled electron transfer (PCET) reactions that form the chemical basis of respiratory and photosynthetic enzymes. Despite recent advances in structural, biophysical, and computational experiments, the mechanistic principles of these reactions still remain elusive. Based on common functional features observed in redox enzymes, we study here generic mechanistic models for water-mediated long-range PCET reactions. We show how a redox reaction within a buried protein environment creates an electric field that induces hydration changes between the proton acceptor and donor groups, and in turn, lowers the reaction barrier and increases the thermodynamic driving forces for the water-mediated PCET process. We predict linear free energy relationships, and discuss the proposed mechanism in context of PCET in cytochrome c oxidase.
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Affiliation(s)
- Patricia Saura
- Center for Integrated Protein Science Munich (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany.
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47
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Todorov AR, Aikonen S, Muuronen M, Helaja J. Visible-Light-Photocatalyzed Reductions of N-Heterocyclic Nitroaryls to Anilines Utilizing Ascorbic Acid Reductant. Org Lett 2019; 21:3764-3768. [PMID: 31066563 PMCID: PMC6750875 DOI: 10.1021/acs.orglett.9b01205] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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A photoreductive
protocol utilizing [Ru(bpy)3]2+ photocatalyst,
blue light LEDs, and ascorbic acid (AscH2) has been developed
to reduce nitro N-heteroaryls to the corresponding
anilines. Based on experimental and computational results and previous
studies, we propose that the reaction proceeds via proton-coupled
electron transfer between AscH2, photocatalyst, and the
nitro N-heteroaryl. The method offers a green catalytic procedure
to reduce, e.g., 4-/8-nitroquinolines to the corresponding aminoquinolines,
substructures present in important antimalarial drugs.
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Affiliation(s)
- Aleksandar R Todorov
- Department of Chemistry , University of Helsinki , A.I. Virtasen aukio 1 , 00014 Helsinki , Finland
| | - Santeri Aikonen
- Department of Chemistry , University of Helsinki , A.I. Virtasen aukio 1 , 00014 Helsinki , Finland
| | - Mikko Muuronen
- Department of Chemistry , University of Helsinki , A.I. Virtasen aukio 1 , 00014 Helsinki , Finland
| | - Juho Helaja
- Department of Chemistry , University of Helsinki , A.I. Virtasen aukio 1 , 00014 Helsinki , Finland
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48
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Wang D, Loose F, Chirik PJ, Knowles RR. N-H Bond Formation in a Manganese(V) Nitride Yields Ammonia by Light-Driven Proton-Coupled Electron Transfer. J Am Chem Soc 2019; 141:4795-4799. [PMID: 30803234 DOI: 10.1021/jacs.8b12957] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A method for the reduction of a manganese nitride to ammonia is reported, where light-driven proton-coupled electron transfer enables the formation of weak N-H bonds. Photoreduction of (saltBu)MnVN to ammonia and a Mn(II) complex has been accomplished using 9,10-dihydroacridine and a combination of an appropriately matched photoredox catalyst and weak Brønsted acid. Acid-reductant pairs with effective bond dissociation free energies between 35 and 46 kcal/mol exhibited high efficiencies. This light-driven method may provide a blueprint for new approaches to catalytic homogeneous ammonia synthesis under ambient conditions.
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Affiliation(s)
- Dian Wang
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Florian Loose
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Paul J Chirik
- 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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49
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Qiao B, Li C, Zhao X, Yin Y, Jiang Z. Enantioselective reduction of azaarene-based ketones via visible light-driven photoredox asymmetric catalysis. Chem Commun (Camb) 2019; 55:7534-7537. [DOI: 10.1039/c9cc03661j] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An enantioselective reduction of azaarene-based ketones through photoredox asymmetric catalysis is reported.
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Affiliation(s)
- Baokun Qiao
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province
- Henan University
- Jinming Campus
- Kaifeng
- P. R. China
| | - Chunyang Li
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province
- Henan University
- Jinming Campus
- Kaifeng
- P. R. China
| | - Xiaowei Zhao
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province
- Henan University
- Jinming Campus
- Kaifeng
- P. R. China
| | - Yanli Yin
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province
- Henan University
- Jinming Campus
- Kaifeng
- P. R. China
| | - Zhiyong Jiang
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province
- Henan University
- Jinming Campus
- Kaifeng
- P. R. China
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50
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Shao Z, Wu Q, Han X, Zhao Y, Xie Q, Wang H, Hou H. Proton coupled electron transfer: novel photochromic performance in a host–guest collaborative MOF. Chem Commun (Camb) 2019; 55:10948-10951. [DOI: 10.1039/c9cc05498g] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Proton coupled electron transfer has been successfully introduced to a host–guest collaborative MOF material, which exhibits novel photochromic properties with reversible, controllable and efficient characteristics.
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Affiliation(s)
- Zhichao Shao
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Qiong Wu
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Xiao Han
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
- College of Chemical Engineering & Material
| | - Yujie Zhao
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Qiong Xie
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Hongfei Wang
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Hongwei Hou
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- P. R. China
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