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Li M, Zhang T, Shi Y, He C, Duan C. Modifying Proton Relay into Bioinspired Dye-Based Coordination Polymer for Photocatalytic Proton-Coupled Electron Transfer. Angew Chem Int Ed Engl 2024; 63:e202406161. [PMID: 38864758 DOI: 10.1002/anie.202406161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 05/23/2024] [Accepted: 06/10/2024] [Indexed: 06/13/2024]
Abstract
Proton-coupled electron transfer (PCET) imparts an energetic advantage over single electron transfer in activating inert substances. Natural PCET enzyme catalysis generally requires tripartite preorganization of proton relay, substrate-bound active center, and redox mediator, making the processes efficient and precluding side reactions. Inspired by this, a heterogeneous photocatalytic PCET system was established to achieve higher PCET driving forces by modifying proton relays into anthraquinone-based anionic coordination polymers. The proximally separated proton relays and photoredox-mediating anthraquinone moiety allowed pre-assembly of inert substrate between them, merging proton and electron into unsaturated bonds by photoreductive PCET, which enhanced reaction kinetics compared with the counter catalyst without proton relay. This photocatalytic PCET method was applied to a broad-scoped reduction of aryl ketones, unsaturated carbonyls, and aromatic compounds. The distinctive regioselectivities for the reduction of isoquinoline derivatives were found to occur on the carbon-ring sides. PCET-generated radical intermediate of quinoline could be trapped by alkene for proton relay-assisted Minisci addition, forming the pharmaceutical aza-acenaphthene scaffold within one step. When using heteroatom(X)-H/C-H compounds as proton-electron donors, this protocol could activate these inert bonds through photooxidative PCET to afford radicals and trap them by electron-deficient unsaturated compounds, furnishing the direct X-H/C-H functionalization.
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Affiliation(s)
- Mochen Li
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, School of Chemistry, Dalian University of Technology, Dalian, 116024, P. R. China
| | - Tiexin Zhang
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, School of Chemistry, Dalian University of Technology, Dalian, 116024, P. R. China
| | - Yusheng Shi
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, School of Chemistry, Dalian University of Technology, Dalian, 116024, P. R. China
| | - Cheng He
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, School of Chemistry, Dalian University of Technology, Dalian, 116024, P. R. China
| | - Chunying Duan
- State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, 210023, P. R. China
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2
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Tanabe Y, Nishibayashi Y. Catalytic Nitrogen Fixation Using Well-Defined Molecular Catalysts under Ambient or Mild Reaction Conditions. Angew Chem Int Ed Engl 2024; 63:e202406404. [PMID: 38781115 DOI: 10.1002/anie.202406404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/21/2024] [Accepted: 05/23/2024] [Indexed: 05/25/2024]
Abstract
Ammonia (NH3) is industrially produced from dinitrogen (N2) and dihydrogen (H2) by the Haber-Bosch process, although H2 is prepared from fossil fuels, and the reaction requires harsh conditions. On the other hand, microorganisms have fixed nitrogen under ambient reaction conditions. Recently, well-defined molecular transition metal complexes have been found to work as catalyst to convert N2 into NH3 by reactions with chemical reductants and proton sources under ambient reaction conditions. Among them, involvement of both N2-splitting pathway and proton-coupled electron transfer is found to be very effective for high catalytic activity. Furthermore, direct electrocatalytic and photocatalytic conversions of N2 into NH3 have been recently achieved. In addition to catalytic formation of NH3, selective catalytic conversion of N2 into hydrazine (NH2NH2) and catalytic silylation of N2 into silylamines have been reported. Catalytic C-N bond formation has been more recently established to afford cyanate anion (NCO-) under ambient reaction conditions. Further development of direct conversion of N2 into nitrogen-containing compounds as well as green ammonia synthesis leading to the use of ammonia as an energy carrier is expected.
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Affiliation(s)
- Yoshiaki Tanabe
- Department of Applied Chemistry, School of Engineering, The University of Tokyo Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Yoshiaki Nishibayashi
- Department of Applied Chemistry, School of Engineering, The University of Tokyo Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
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Chatgilialoglu C, Barata-Vallejo S, Gimisis T. Radical Reactions in Organic Synthesis: Exploring in-, on-, and with-Water Methods. Molecules 2024; 29:569. [PMID: 38338314 PMCID: PMC10856544 DOI: 10.3390/molecules29030569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024] Open
Abstract
Radical reactions in water or aqueous media are important for organic synthesis, realizing high-yielding processes under non-toxic and environmentally friendly conditions. This overview includes (i) a general introduction to organic chemistry in water and aqueous media, (ii) synthetic approaches in, on, and with water as well as in heterogeneous phases, (iii) reactions of carbon-centered radicals with water (or deuterium oxide) activated through coordination with various Lewis acids, (iv) photocatalysis in water and aqueous media, and (v) synthetic applications bioinspired by naturally occurring processes. A wide range of chemical processes and synthetic strategies under different experimental conditions have been reviewed that lead to important functional group translocation and transformation reactions, leading to the preparation of complex molecules. These results reveal how water as a solvent/medium/reagent in radical chemistry has matured over the last two decades, with further discoveries anticipated in the near future.
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Affiliation(s)
- Chryssostomos Chatgilialoglu
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Center of Advanced Technologies, Adam Mickiewicz University, 61-712 Poznan, Poland
| | - Sebastian Barata-Vallejo
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Facultad de Farmacia y Bioquímica, Departamento de Ciencias Químicas, Universidad de Buenos Aires, Junin 954, Buenos Aires CP 1113, Argentina
| | - Thanasis Gimisis
- Department of Chemistry, National and Kapodistrian University of Athens, 15771 Athens, Greece
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Abstract
Coordination-induced bond weakening is a phenomenon wherein ligand X-H bond homolysis occurs in concert with the energetically favorable oxidation of a coordinating metal complex. The coupling of these two processes enables thermodynamically favorable proton-coupled electron transfer reductions to form weak bonds upon formal hydrogen atom transfer to substrates. Moreover, systems utilizing coordination-induced bond weakening have been shown to facilitate the dehydrogenation of feedstock molecules including water, ammonia, and primary alcohols under mild conditions. The formation of exceptionally weak substrate X-H bonds via small molecule homolysis is a powerful strategy in synthesis and has been shown to enable nitrogen fixation under mild conditions. Coordination-induced bond weakening has also been identified as an integral process in biophotosynthesis and has promising applications in renewable chemical fuel storage systems. This review presents a discussion of the advances made in the study of coordination-induced bond weakening to date. Because of the broad range of metal and ligand species implicated in coordination-induced bond weakening, each literature report is discussed individually and ordered by the identity of the low-valent metal. We then offer mechanistic insights into the basis of coordination-induced bond weakening and conclude with a discussion of opportunities for further research into the development and applications of coordination-induced bond weakening systems.
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Affiliation(s)
- Nicholas G Boekell
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Robert A Flowers
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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5
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Ramírez-Solís A, Boekell NG, León-Pimentel CI, Saint-Martin H, Bartulovich CO, Flowers RA. Ammonia Solvation vs Aqueous Solvation of Samarium Diiodide. A Theoretical and Experimental Approach to Understanding Bond Activation Upon Coordination to Sm(II). J Org Chem 2021; 87:1689-1697. [PMID: 34775764 DOI: 10.1021/acs.joc.1c01771] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Coordination-induced desolvation or ligand displacement by cosolvents and additives is a key feature responsible for the reactivity of Sm(II)-based reagent systems. High-affinity proton donor cosolvents such as water and glycols also demonstrate coordination-induced bond weakening of the O-H bond, facilitating reduction of a broad range of substrates. In the present work, the coordination of ammonia to SmI2 was examined using Born-Oppenheimer molecular dynamics simulations and mechanistic studies, and the SmI2-ammonia system is compared to the SmI2-water system. The coordination number and reactivity of the SmI2-ammonia solvent system were found to be similar to those of SmI2-water but exhibited an order of magnitude greater rate of arene reduction by SmI2-ammonia than by SmI2-water at the same concentrations of cosolvent. In addition, upon coordination of ammonia to SmI2, the Sm(II)-ammonia solvate demonstrates one of the largest degrees of N-H bond weakening reported in the literature compared to known low-valent transition metal ammonia complexes.
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Affiliation(s)
- Alejandro Ramírez-Solís
- Depto. de Física, Centro de Investigación en Ciencias-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos 62209, México
| | - Nicholas G Boekell
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | | | | | - Caroline O Bartulovich
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Robert A Flowers
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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Tanabe Y, Nishibayashi Y. Comprehensive insights into synthetic nitrogen fixation assisted by molecular catalysts under ambient or mild conditions. Chem Soc Rev 2021; 50:5201-5242. [PMID: 33651046 DOI: 10.1039/d0cs01341b] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
N2 is fixed as NH3 industrially by the Haber-Bosch process under harsh conditions, whereas biological nitrogen fixation is achieved under ambient conditions, which has prompted development of alternative methods to fix N2 catalyzed by transition metal molecular complexes. Since the early 21st century, catalytic conversion of N2 into NH3 under ambient conditions has been achieved by using molecular catalysts, and now H2O has been utilized as a proton source with turnover frequencies reaching the values found for biological nitrogen fixation. In this review, recent advances in the development of molecular catalysts for synthetic N2 fixation under ambient or mild conditions are summarized, and potential directions for future research are also discussed.
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Affiliation(s)
- Yoshiaki Tanabe
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
| | - Yoshiaki Nishibayashi
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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7
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Ramírez-Solís A, Bartulovich CO, León-Pimentel CI, Saint-Martin H, Anderson WR, Flowers RA. Experimental and Theoretical Studies on the Aqueous Solvation and Reactivity of SmCl2 and Comparison with SmBr2 and SmI2. Inorg Chem 2019; 58:13927-13932. [DOI: 10.1021/acs.inorgchem.9b01818] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Alejandro Ramírez-Solís
- Departamento de Física, Centro de Investigación en Ciencias-IICBA Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos 62209, Mexico
| | | | | | | | - William R. Anderson
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Robert A. Flowers
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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8
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Lachtar Z, Khorief Nacereddine A, Djerourou A. Understanding the origin of the enantioselectivity and the mechanism of the asymmetric reduction of ketimine generated from acetophenone with oxazaborolidine catalyst. Struct Chem 2019. [DOI: 10.1007/s11224-019-01400-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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9
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Chiral (cyclopentadienone)iron complexes with a stereogenic plane as pre-catalysts for the asymmetric hydrogenation of polar double bonds. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.01.057] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Abstract
Ligation plays a multifaceted role in the chemistry of SmI2. Depending on the ligand, two of its major effects are increasing the reduction potential of SmI2, and in the case of a ligand, which is also a proton donor, it may also enhance the reaction by protonation of the radical anion generated in the preceding step. It turns out that the number of ligand molecules that are needed to maximize the reduction potential of SmI2 is significantly smaller than the number of ligand molecules needed for a maximal enhancement of the protonation rate. In addition to the economical use of the ligand, this information can also be utilized as a diagnostic tool for the reaction mechanism in differentiating between single and multistep processes. The possible pitfalls in applying this diagnostic tool to PCET and cyclization reactions are discussed.
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Affiliation(s)
- Sandeepan Maity
- Department of Chemistry , Bar-Ilan University , Ramat Gan 5290002 , Israel
| | - Amey Nimkar
- Department of Chemistry , Bar-Ilan University , Ramat Gan 5290002 , Israel
| | - Shmaryahu Hoz
- Department of Chemistry , Bar-Ilan University , Ramat Gan 5290002 , Israel
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11
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Resa S, Millán A, Fuentes N, Crovetto L, Luisa Marcos M, Lezama L, Choquesillo-Lazarte D, Blanco V, Campaña AG, Cárdenas DJ, Cuerva JM. O–H and (CO)N–H bond weakening by coordination to Fe(ii). Dalton Trans 2019; 48:2179-2189. [DOI: 10.1039/c8dt04689a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Coordination of hydroxyl/amide groups to Fe(ii) diminishes BDFEs of O–H and (CO)N–H bonds down to 76.0 and 80.5 kcal mol−1 respectively.
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12
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Ramírez-Solís A, Bartulovich CO, Chciuk TV, Hernández-Cobos J, Saint-Martin H, Maron L, Anderson WR, Li AM, Flowers RA. Experimental and Theoretical Studies on the Implications of Halide-Dependent Aqueous Solvation of Sm(II). J Am Chem Soc 2018; 140:16731-16739. [DOI: 10.1021/jacs.8b09857] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Alejandro Ramírez-Solís
- Departamento de Física, Centro de Investigación en Ciencias-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos 62209 México
| | | | - Tesia V. Chciuk
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Jorge Hernández-Cobos
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - Humberto Saint-Martin
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - Laurent Maron
- Laboratoire de Physique et Chimie de Nano-objets, Université de Toulouse, INSA-CNRS-UPS, 135, Avenue de Rangueil, 31077 Toulouse, France
| | - William R. Anderson
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Anna M. Li
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Robert A. Flowers
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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13
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Chciuk TV, Anderson WR, Flowers RA. Interplay between Substrate and Proton Donor Coordination in Reductions of Carbonyls by SmI2–Water Through Proton-Coupled Electron-Transfer. J Am Chem Soc 2018; 140:15342-15352. [DOI: 10.1021/jacs.8b08890] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Tesia V. Chciuk
- Department of Chemistry, Lehigh University, 6 E. Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - William R. Anderson
- Department of Chemistry, Lehigh University, 6 E. Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Robert A. Flowers
- Department of Chemistry, Lehigh University, 6 E. Packer Avenue, Bethlehem, Pennsylvania 18015, United States
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14
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Huang HM, Procter DJ. Selective Electron Transfer Reduction of Urea-Type Carbonyls. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800794] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Huan-Ming Huang
- School of Chemistry; University of Manchester; Oxford Road Manchester, M13 9PL UK
| | - David J. Procter
- School of Chemistry; University of Manchester; Oxford Road Manchester, M13 9PL UK
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15
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Cheisson T, Ricard L, Heinemann FW, Meyer K, Auffrant A, Nocton G. Synthesis and Reactivity of Low-Valent f-Element Iodide Complexes with Neutral Iminophosphorane Ligands. Inorg Chem 2018; 57:9230-9240. [DOI: 10.1021/acs.inorgchem.8b01259] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Thibault Cheisson
- LCM, Ecole Polytechnique, CNRS, Université Paris-Saclay, F-91128 Palaiseau Cedex, France
| | - Louis Ricard
- LCM, Ecole Polytechnique, CNRS, Université Paris-Saclay, F-91128 Palaiseau Cedex, France
| | - Frank W. Heinemann
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058 Erlangen, Germany
| | - Karsten Meyer
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058 Erlangen, Germany
| | - Audrey Auffrant
- LCM, Ecole Polytechnique, CNRS, Université Paris-Saclay, F-91128 Palaiseau Cedex, France
| | - Grégory Nocton
- LCM, Ecole Polytechnique, CNRS, Université Paris-Saclay, F-91128 Palaiseau Cedex, France
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16
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Yang JD, Ji P, Xue XS, Cheng JP. Recent Advances and Advisable Applications of Bond Energetics in Organic Chemistry. J Am Chem Soc 2018; 140:8611-8623. [DOI: 10.1021/jacs.8b04104] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jin-Dong Yang
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Pengju Ji
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Xiao-Song Xue
- State Key Laboratory of Elemento-organic Chemistry, Collaborative Innovation Centre of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jin-Pei Cheng
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
- State Key Laboratory of Elemento-organic Chemistry, Collaborative Innovation Centre of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
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You B, Shen M, Xie G, Mao H, Lv X, Wang X. Alternative Sm(II) Species-Mediated Cascade Coupling/Cyclization for the Synthesis of Oxobicyclo[3.1.0]hexane-1-ols. Org Lett 2018; 20:530-533. [DOI: 10.1021/acs.orglett.7b03613] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Bingxin You
- Department
of Chemistry, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People’s Republic of China
| | - Mengmeng Shen
- Department
of Chemistry, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People’s Republic of China
| | - Guanqun Xie
- Department
of Chemistry, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People’s Republic of China
- School
of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, 523808, People’s Republic of China
| | - Hui Mao
- Department
of Chemistry, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People’s Republic of China
| | - Xin Lv
- Department
of Chemistry, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People’s Republic of China
| | - Xiaoxia Wang
- Department
of Chemistry, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People’s Republic of China
- School
of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, 523808, People’s Republic of China
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