1
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Monteith JJ, Rousseaux SAL. A Dual Ni/Photoredox Cross-Coupling Approach toward Mandelic Acids. Org Lett 2024; 26:4566-4570. [PMID: 38758597 DOI: 10.1021/acs.orglett.4c01547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2024]
Abstract
Mandelic acid derivatives represent a valuable class of compounds due to their wide use in synthetic organic chemistry and the pharmaceutical sector. Herein, we report a novel reductive Ni/photoredox cross-coupling of readily accessible, bench stable N-alkoxyphthalimides and aryl halides to prepare unprotected mandelic acid ester derivatives. Mechanistic experiments suggest that this cross-coupling likely proceeds via a pathway that is distinct from previous reports using similar redox-active alkoxy radical precursors.
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Affiliation(s)
- John J Monteith
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Sophie A L Rousseaux
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
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2
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Man Y, Xu B. Generation and Radical-Radical Cross-Coupling of Alkenyloxy Radical. Org Lett 2024. [PMID: 38502939 DOI: 10.1021/acs.orglett.4c00627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Alkene-attached oxygen radicals are rarely used, as highly reactive oxygen radicals are incompatible with the alkene moiety. The direct radical-radical cross-coupling of O radicals is also challenging (limited to N-O bond formation) because of the lack of suitable persistent radical species. This study demonstrated the feasibility of using Breslow intermediate radical (BIR) as a persistent radical to capture unstable π-conjugated O radicals and allow the C-O radical-radical cross-coupling.
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Affiliation(s)
- Yunquan Man
- Key Laboratory of Science and Technology of Eco-Textiles, Ministry of Education, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China
| | - Bo Xu
- Key Laboratory of Science and Technology of Eco-Textiles, Ministry of Education, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China
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3
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Chen QC, Kress S, Molinelli R, Wuttig A. Interfacial Tuning of Electrocatalytic Ag Surfaces for Fragment-Based Electrophile Coupling. Nat Catal 2024; 7:120-131. [PMID: 38434422 PMCID: PMC10906991 DOI: 10.1038/s41929-023-01073-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 11/02/2023] [Indexed: 03/05/2024]
Abstract
Construction of C‒C bonds in medicinal chemistry frequently draws on the reductive coupling of organic halides with ketones or aldehydes. Catalytic C(sp3)‒C(sp3) bond formation, however, is constrained by the competitive side reactivity of radical intermediates following sp3 organic halide activation. Here, an alternative paradigm deploys catalytic Ag surfaces for reductive fragment-based electrophile coupling compatible with sp3 organic halides. We use in-situ spectroscopy, electrochemical analyses, and simulation to uncover the catalytic interfacial structure and guide reaction development. Specifically, Mg(OAc)2 outcompetes the interaction between Ag and the aldehyde, thereby tuning the Ag surface for selective product formation. Data are consistent with an increased population of Mg-bound aldehyde facilitating the addition of a carbon-centered radical (product of Ag-electrocatalyzed organic halide reduction) to the carbonyl. Electron transfer from Ag to the resultant alkoxy radical yields the desired alcohol. Molecular interfacial tuning at reusable catalytic electrodes will accelerate development of sustainable organic synthetic methods.
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Affiliation(s)
- Qiu-Cheng Chen
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, United States
| | - Sarah Kress
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, United States
| | - Rocco Molinelli
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, United States
| | - Anna Wuttig
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, United States
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4
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Chicas-Baños DF, López-Rivas M, González-Bravo FJ, Sartillo-Piscil F, Frontana-Uribe BA. Access to carbonyl compounds via the electroreduction of N-benzyloxyphthalimides: Mechanism confirmation and preparative applications. Heliyon 2024; 10:e23808. [PMID: 38226225 PMCID: PMC10788431 DOI: 10.1016/j.heliyon.2023.e23808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 12/10/2023] [Accepted: 12/13/2023] [Indexed: 01/17/2024] Open
Abstract
A method to access carbonyl compounds using reductive conditions was evaluated via electrochemical reduction of their corresponding N-benzyloxyphthalimide derivatives (NBOPIs). The mechanism of this originally reported electrochemical reaction was proposed based on DFT calculation and is experimentally confirmed herein, contrasting simulated and experimental cyclic voltammetry data. The reaction scope studied in a preparative scale and using redox sensitive functional groups showed good selectivity and tolerance toward oxidation under the reaction conditions with a moderate to good yield (50-71%). Nevertheless, some restrictions with reducible functional groups, like benzyl-brominated and nitro-aromatic derivatives, were observed. The present approach can be considered a self-sustainable electrochemical catalysis for the synthesis of aromatic carbonylic compounds passing through anion radical intermediates produced by a cathodic reaction.
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Affiliation(s)
- Diego Francisco Chicas-Baños
- Universidad de El Salvador (UES), Facultad de Ciencias Naturales y Matemática, Escuela de Química, Final 25 Av. Nte, 1101, San Salvador, El Salvador
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Mexico City, 04510, Mexico
| | - Mariely López-Rivas
- Centro Conjunto Química Sustentable UAEMéx-UNAM, Km 14.5 Carretera Toluca-Ixtlahuaca, Toluca, 50200, Estado de México, Mexico
| | - Felipe J. González-Bravo
- Departamento de Química, Centro de Investigación y Estudios Avanzados, Av. Instituto Politécnico Nacional 2508, 07360, Mexico City, Mexico
| | - Fernando Sartillo-Piscil
- Centro de Investigación de la Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla (BUAP), 14 Sur Esq. San Claudio, Col. San Manuel, 72570, Puebla, Mexico
| | - Bernardo Antonio Frontana-Uribe
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Mexico City, 04510, Mexico
- Centro Conjunto Química Sustentable UAEMéx-UNAM, Km 14.5 Carretera Toluca-Ixtlahuaca, Toluca, 50200, Estado de México, Mexico
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5
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Li Y, Guo S, Li QH, Zheng K. Metal-free photoinduced C(sp 3)-H/C(sp 3)-H cross-coupling to access α‑tertiary amino acid derivatives. Nat Commun 2023; 14:6225. [PMID: 37802984 PMCID: PMC10558569 DOI: 10.1038/s41467-023-41956-6] [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: 03/31/2023] [Accepted: 09/22/2023] [Indexed: 10/08/2023] Open
Abstract
The cross-dehydrogenative coupling (CDC) reaction is the most direct and efficient method for constructing α-tertiary amino acids (ATAAs), which avoids the pre-activation of C(sp3)-H substrates. However, the use of transition metals and harsh reaction conditions are still significant challenges for these reactions that urgently require solutions. This paper presents a mild, metal-free CDC reaction for the construction of ATAAs, which is compatible with various benzyl C-H substrates, functionalized C-H substrates, and alkyl substrates, with good regioselectivity. Notably, our method exhibits excellent functional group tolerance and late-stage applicability. According to mechanistic studies, the one-step synthesized and bench-stable N-alkoxyphtalimide generates a highly electrophilic trifluoro ethoxy radical that serves as a key intermediate in the reaction process and acts as a hydrogen atom transfer reagent. Therefore, our metal-free and additive-free method offers a promising strategy for the synthesis of ATAAs under mild conditions.
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Affiliation(s)
- Yujun Li
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, PR China
| | - Shaopeng Guo
- Key Laboratory of General Chemistry of the National Ethnic Affairs Commission, College of Chemistry and Environment, Southwest Minzu University, Chengdu, PR China
| | - Qing-Han Li
- Key Laboratory of General Chemistry of the National Ethnic Affairs Commission, College of Chemistry and Environment, Southwest Minzu University, Chengdu, PR China
| | - Ke Zheng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, PR China.
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6
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Chabuka BK, Alabugin IV. Hole Catalysis of Cycloaddition Reactions: How to Activate and Control Oxidant Upconversion in Radical-Cationic Diels-Alder Reactions. J Am Chem Soc 2023; 145:19354-19367. [PMID: 37625247 DOI: 10.1021/jacs.3c06106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2023]
Abstract
In order to use holes as catalysts, the oxidized product should be able to transfer the hole to a fresh reactant. For that, the hole-catalyzed reaction must increase the oxidation potential along the reaction path, i.e., lead to "hole upconversion." If this thermodynamic requirement is satisfied, a hole injected via one-electron oxidation can persist through multiple propagation cycles and serve as a true catalyst. This work provides guidelines for the rational design of hole-catalyzed Diels-Alder (DA) reactions, the prototypical cycloaddition. After revealing the crucial role of hyperconjugation in the absence of hole upconversion in the parent DA reaction, we show how upconversion can be reactivated by proper substitution. For this purpose, we computationally evaluate the contrasting effects of substituents at the three possible positions in the two reactants. The occurrence and magnitude of hole upconversion depend strongly on the placement and nature of substituents. For example, donors at C1 in 1,3-butadiene shift the reaction to the hole-upconverted regime with an increased oxidation potential of up to 1.0 V. In contrast, hole upconversion in C2-substituted 1,3-butadienes is activated by acceptors with the oxidation potential increase up to 0.54 V. Dienophile substitution results in complex trends because the radical cation can be formed at either the dienophile or the diene. Hole upconversion is always present in the former scenario (up to 0.65 V). Finally, we report interesting stereoelectronic effects that can activate or deactivate upconversion via a conformational change.
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Affiliation(s)
- Beauty K Chabuka
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Igor V Alabugin
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
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7
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El Gehani AAMA, Maashi HA, Harnedy J, Morrill LC. Electrochemical generation and utilization of alkoxy radicals. Chem Commun (Camb) 2023; 59:3655-3664. [PMID: 36877137 DOI: 10.1039/d3cc00302g] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
This highlight summarises electrochemical approaches for the generation and utilization of alkoxy radicals, predominantly focusing on recent advances (2012-present). The application of electrochemically generated alkoxy radicals in a diverse range of transformations is described, including discussion on reaction mechanisms, scope and limitations, in addition to highlighting future challenges in this burgeoning area of sustainable synthesis.
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Affiliation(s)
- Albara A M A El Gehani
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK.
| | - Hussain A Maashi
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK.
| | - James Harnedy
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK.
| | - Louis C Morrill
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK.
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8
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Rapisarda L, Fermi A, Ceroni P, Giovanelli R, Bertuzzi G, Bandini M. Electrochemical C(sp 3)-H functionalization of ethers via hydrogen-atom transfer by means of cathodic reduction. Chem Commun (Camb) 2023; 59:2664-2667. [PMID: 36785969 DOI: 10.1039/d2cc06999g] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The chemo- and stereoselective electrochemical allylation/alkylation of ethers is presented via a C(sp3)-H activation event. The electrosynthetic protocol enables the realization of a large library of functionalized ethers (35 examples) in high yields (up to 84%) via cathodic activation of a new type of redox-active carbonate (RAC), capable of triggering HAT (Hydrogen-Atom-Transfer) events through the generation of electrophilic oxy radicals. The process displayed high functional group tolerance and mild reaction conditions. A mechanistic elucidation via voltammetric analysis completes the study.
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Affiliation(s)
- Leonardo Rapisarda
- Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum - Università di Bologna, via Selmi 2, 40126, Bologna, Italy.
| | - Andrea Fermi
- Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum - Università di Bologna, via Selmi 2, 40126, Bologna, Italy. .,Center for Chemical Catalysis - C3, Alma Mater Studiorum - Università di Bologna Via Selmi 2, 40126, Bologna, Italy
| | - Paola Ceroni
- Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum - Università di Bologna, via Selmi 2, 40126, Bologna, Italy. .,Center for Chemical Catalysis - C3, Alma Mater Studiorum - Università di Bologna Via Selmi 2, 40126, Bologna, Italy
| | - Riccardo Giovanelli
- Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum - Università di Bologna, via Selmi 2, 40126, Bologna, Italy. .,Center for Chemical Catalysis - C3, Alma Mater Studiorum - Università di Bologna Via Selmi 2, 40126, Bologna, Italy
| | - Giulio Bertuzzi
- Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum - Università di Bologna, via Selmi 2, 40126, Bologna, Italy. .,Center for Chemical Catalysis - C3, Alma Mater Studiorum - Università di Bologna Via Selmi 2, 40126, Bologna, Italy
| | - Marco Bandini
- Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum - Università di Bologna, via Selmi 2, 40126, Bologna, Italy. .,Center for Chemical Catalysis - C3, Alma Mater Studiorum - Università di Bologna Via Selmi 2, 40126, Bologna, Italy
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9
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Balycheva VA, Akyeva AY, Saverina EA, Shangin PG, Krylova IV, Korolev VA, Egorov MP, Alabugin IV, Syroeshkin MA. Electron upconversion in reactions of 1,2,4-triazoline-3,5-dione. Russ Chem Bull 2022. [DOI: 10.1007/s11172-022-3570-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Budnikov AS, Krylov I, Lastovko AV, Yu B, Terent'ev AO. N‐Alkoxyphtalimides as Versatile Alkoxy Radical Precursors in Modern Organic Synthesis. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202200262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Alexander S. Budnikov
- Zelinsky Institute of Organic Chemistry RAS: Institut organiceskoj himii imeni N D Zelinskogo RAN Laboratory for Studies of Homolytic Reactions RUSSIAN FEDERATION
| | - Igor Krylov
- Zelinsky Institute of Organic Chemistry RAS: Institut organiceskoj himii imeni N D Zelinskogo RAN Laboratory for Studies of Homolytic Reactions Leninsky Prospect, 47 119991 Moscow RUSSIAN FEDERATION
| | - Andrey V. Lastovko
- Zelinsky Institute of Organic Chemistry RAS: Institut organiceskoj himii imeni N D Zelinskogo RAN Laboratory for Studies of Homolytic Reactions RUSSIAN FEDERATION
| | - Bing Yu
- Zhengzhou University Green Catalysis Center CHINA
| | - Alexander O. Terent'ev
- Zelinsky Institute of Organic Chemistry RAS: Institut organiceskoj himii imeni N D Zelinskogo RAN Laboratory for Studies of Homolytic Reactions Leninsky prospekt 47 119991 Moscow RUSSIAN FEDERATION
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11
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Hareram MD, El Gehani AAMA, Harnedy J, Seastram AC, Jones AC, Burns M, Wirth T, Browne DL, Morrill LC. Electrochemical Deconstructive Functionalization of Cycloalkanols via Alkoxy Radicals Enabled by Proton-Coupled Electron Transfer. Org Lett 2022; 24:3890-3895. [PMID: 35604008 PMCID: PMC9171832 DOI: 10.1021/acs.orglett.2c01552] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
![]()
Herein, we report
a new electrochemical method for alkoxy radical
generation from alcohols using a proton-coupled electron transfer
(PCET) approach, showcased via the deconstructive functionalization
of cycloalkanols. The electrochemical method is applicable across
a diverse array of substituted cycloalkanols, accessing a broad range
of synthetically useful distally functionalized ketones. The orthogonal
derivatization of the products has been demonstrated through chemoselective
transformations, and the electrochemical process has been performed
on a gram scale in continuous single-pass flow.
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Affiliation(s)
- Mishra Deepak Hareram
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Albara A. M. A. El Gehani
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - James Harnedy
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Alex C. Seastram
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Andrew C. Jones
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Matthew Burns
- Chemical Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Macclesfield, SK10 2NA, United Kingdom
| | - Thomas Wirth
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Duncan L. Browne
- Department of Pharmaceutical and Biological Chemistry, University College London, School of Pharmacy, London, W1CN 1AX, United Kingdom
| | - Louis C. Morrill
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
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12
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Owatari Y, Iseki S, Ogata D, Yuasa J. Catalytic electron drives host–guest recognition. Chem Sci 2022; 13:5261-5267. [PMID: 35655551 PMCID: PMC9093170 DOI: 10.1039/d2sc01342h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/03/2022] [Indexed: 01/17/2023] Open
Abstract
The reactants of AQH–CH2CN are converted into AQ and CH3CN in sustainable electrocatalytic chain reactions, successfully achieving catalytic electron-triggered charge-transfer (CT) complex formation.
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Affiliation(s)
- Yoshihiro Owatari
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - Shuta Iseki
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - Daiji Ogata
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - Junpei Yuasa
- Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
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13
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Bugaenko DI, Karchava AV, Yurovskaya MA. Transition metal-free cross-coupling reactions with the formation of carbon-heteroatom bonds. RUSSIAN CHEMICAL REVIEWS 2022. [DOI: 10.1070/rcr5022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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A general strategy for C(sp 3)-H functionalization with nucleophiles using methyl radical as a hydrogen atom abstractor. Nat Commun 2021; 12:6950. [PMID: 34845207 PMCID: PMC8630022 DOI: 10.1038/s41467-021-27165-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 11/04/2021] [Indexed: 11/08/2022] Open
Abstract
Photoredox catalysis has provided many approaches to C(sp3)-H functionalization that enable selective oxidation and C(sp3)-C bond formation via the intermediacy of a carbon-centered radical. While highly enabling, functionalization of the carbon-centered radical is largely mediated by electrophilic reagents. Notably, nucleophilic reagents represent an abundant and practical reagent class, motivating the interest in developing a general C(sp3)-H functionalization strategy with nucleophiles. Here we describe a strategy that transforms C(sp3)-H bonds into carbocations via sequential hydrogen atom transfer (HAT) and oxidative radical-polar crossover. The resulting carbocation is functionalized by a variety of nucleophiles-including halides, water, alcohols, thiols, an electron-rich arene, and an azide-to effect diverse bond formations. Mechanistic studies indicate that HAT is mediated by methyl radical-a previously unexplored HAT agent with differing polarity to many of those used in photoredox catalysis-enabling new site-selectivity for late-stage C(sp3)-H functionalization.
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15
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Chicas-Baños DF, Frontana-Uribe BA. Electrochemical Generation and Use in Organic Synthesis of C-, O-, and N-Centered Radicals. CHEM REC 2021; 21:2538-2573. [PMID: 34047059 DOI: 10.1002/tcr.202100056] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/28/2021] [Accepted: 05/03/2021] [Indexed: 12/23/2022]
Abstract
During the last decade several research groups have been developing electrochemical procedures to access highly functionalized organic molecules. Among the most exciting advances, the possibility of using free radical chemistry has attracted the attention of the most important synthetic groups. Nowadays, electrochemical strategies based on these species with a synthetic purpose are published continuously in scientific journals, increasing the alternatives for the synthetic organic chemistry laboratories. Free radicals can be obtained in organic electrochemical reactions; thus, this review reassembles the last decade's (2010-2020) efforts of the electrosynthetic community to generate and take advantage of the C-, O-, and N-centered radicals' reactivity. The electrochemical reactions that occur, as well as the proposed mechanism, are discussed, trying to give clear information about the used conditions and reactivity of these reactive intermediate species.
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Affiliation(s)
- Diego Francisco Chicas-Baños
- Centro Conjunto Química Sustentable UAEMéx-UNAM, Km 14.5 Carretera Toluca-Ixtlahuaca, Toluca, 50200, Estado de México, Mexico
| | - Bernardo A Frontana-Uribe
- Centro Conjunto Química Sustentable UAEMéx-UNAM, Km 14.5 Carretera Toluca-Ixtlahuaca, Toluca, 50200, Estado de México, Mexico.,Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Ciudad de México, 04510, Mexico
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16
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Bhanage BM, Subramanian K, Yedage SL, Sethi K. Tetrabutylammonium Iodide (TBAI) Catalyzed Electrochemical C–H Bond Activation of 2-Arylated N-Methoxyamides for the Synthesis of Phenanthridinones. Synlett 2021. [DOI: 10.1055/a-1467-5585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
AbstractAn electrochemical method for the synthesis of phenanthridinones through constant-potential electrolysis (CPE) mediated by Bu4NI (TBAI) is reported. The protocol is metal and oxidant free, and proceeds with 100% current efficiency. TBAI plays a dual role as both a redox catalyst and a supporting electrolyte. The intramolecular C–H activation proceeds under mild reaction conditions and with a short reaction time through electrochemically generated amidyl radicals. The reaction has been scaled up to a gram level, showing its practicability, and the synthetic utility and applicability of the protocol have been demonstrated by a direct one-step synthesis of the bioactive compound phenaglaydon.
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17
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Chen N, Ye Z, Zhang F. Recent progress on electrochemical synthesis involving carboxylic acids. Org Biomol Chem 2021; 19:5501-5520. [PMID: 34079974 DOI: 10.1039/d1ob00420d] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Carboxylic acids are not only essential sections of medicinal molecules, natural products and agrochemicals but also basic building blocks for organic synthesis. However, high temperature, expensive catalysts and excess oxidants are normally required for carboxylic acid group transformations. Therefore, more eco-friendly and efficient methods are urgently needed. Organic electrochemistry, as an environmentally friendly and sustainable synthetic method, can potentially avoid the above problems and is favored by more and more organic chemists. This review summarized the recent progress on the electrochemical synthesis of carboxylic acids to construct more complex compounds, emphasizing the development of electrosynthesis methodologies and mechanisms in order to attract more chemists to recognize the importance and applications of electrochemical synthesis.
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Affiliation(s)
- Na Chen
- College of Pharmaceutical Science, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, Zhejiang 310014, China.
| | - Zenghui Ye
- College of Pharmaceutical Science, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, Zhejiang 310014, China.
| | - Fengzhi Zhang
- College of Pharmaceutical Science, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, Zhejiang 310014, China.
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18
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Crespi S, Fagnoni M. Generation of Alkyl Radicals: From the Tyranny of Tin to the Photon Democracy. Chem Rev 2020; 120:9790-9833. [PMID: 32786419 PMCID: PMC8009483 DOI: 10.1021/acs.chemrev.0c00278] [Citation(s) in RCA: 189] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Indexed: 01/09/2023]
Abstract
Alkyl radicals are key intermediates in organic synthesis. Their classic generation from alkyl halides has a severe drawback due to the employment of toxic tin hydrides to the point that "flight from the tyranny of tin" in radical processes was considered for a long time an unavoidable issue. This review summarizes the main alternative approaches for the generation of unstabilized alkyl radicals, using photons as traceless promoters. The recent development in photochemical and photocatalyzed processes enabled the discovery of a plethora of new alkyl radical precursors, opening the world of radical chemistry to a broader community, thus allowing a new era of photon democracy.
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Affiliation(s)
- Stefano Crespi
- Stratingh
Institute for Chemistry, Center for Systems
Chemistry University of Groningen, Nijenborgh 4, 9747
AG Groningen, The Netherlands
| | - Maurizio Fagnoni
- PhotoGreen
Lab, Department of Chemistry, V. Le Taramelli 10, 27100 Pavia, Italy
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19
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Taking electrodecarboxylative etherification beyond Hofer-Moest using a radical C-O coupling strategy. Nat Commun 2020; 11:4407. [PMID: 32879323 PMCID: PMC7468261 DOI: 10.1038/s41467-020-18275-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/12/2020] [Indexed: 11/08/2022] Open
Abstract
Established electrodecarboxylative etherification protocols are based on Hofer-Moest-type reaction pathways. An oxidative decarboxylation gives rise to radicals, which are further oxidised to carbocations. This is possible only for benzylic or otherwise stabilised substrates. Here, we report the electrodecarboxylative radical-radical coupling of lithium alkylcarboxylates with 1-hydroxybenzotriazole at platinum electrodes in methanol/pyridine to afford alkyl benzotriazole ethers. The substrate scope of this electrochemical radical coupling extends to primary and secondary alkylcarboxylates. The benzotriazole products easily undergo reductive cleavage to the alcohols. They can also serve as synthetic hubs to access a wide variety of functional groups. This reaction prototype demonstrates that electrodecarboxylative C-O bond formation can be taken beyond the intrinsic substrate limitations of Hofer-Moest mechanisms.
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20
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Paveliev SA, Churakov AI, Alimkhanova LS, Segida OO, Nikishin GI, Terent'ev AO. Electrochemical Synthesis of
O
‐Phthalimide Oximes from
α
‐Azido Styrenes
via
Radical Sequence: Generation, Addition and Recombination of Imide‐
N
‐Oxyl and Iminyl Radicals with C−O/N−O Bonds Formation. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000618] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Stanislav A. Paveliev
- N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences 47 Leninsky prosp. Moscow 119991 Russian Federation
| | - Artem I. Churakov
- N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences 47 Leninsky prosp. Moscow 119991 Russian Federation
| | - Liliya S. Alimkhanova
- N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences 47 Leninsky prosp. Moscow 119991 Russian Federation
| | - Oleg O. Segida
- N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences 47 Leninsky prosp. Moscow 119991 Russian Federation
| | - Gennady I. Nikishin
- N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences 47 Leninsky prosp. Moscow 119991 Russian Federation
| | - Alexander O. Terent'ev
- N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences 47 Leninsky prosp. Moscow 119991 Russian Federation
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21
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N-(Alkoxy)- and N-(acyloxy)phthalimides in organic synthesis: free radical synthetic approaches and applications (microreview). Chem Heterocycl Compd (N Y) 2020. [DOI: 10.1007/s10593-020-02618-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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22
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Paulisch TO, Strieth-Kalthoff F, Henkel C, Pitzer L, Guldi DM, Glorius F. Chain propagation determines the chemo- and regioselectivity of alkyl radical additions to C-O vs. C-C double bonds. Chem Sci 2020; 11:731-736. [PMID: 33209246 PMCID: PMC7640737 DOI: 10.1039/c9sc04846d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 11/25/2019] [Indexed: 11/23/2022] Open
Abstract
Investigations into the selectivity of intermolecular alkyl radical additions to C-O- vs. C-C-double bonds in α,β-unsaturated carbonyl compounds are described. Therefore, a photoredox-initiated radical chain reaction is explored, where the activation of the carbonyl-group through an in situ generated Lewis acid - originating from the substrate - enables the formation of either C-O or the C-C-addition products. α,β-Unsaturated aldehydes form selectively 1,2-, while esters and ketones form the corresponding 1,4-addition products exclusively. Computational studies lead to reason that this chemo- and regioselectivity is determined by the consecutive step, i.e. an electron transfer, after reversible radical addition, which eventually propagates the radical chain.
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Affiliation(s)
- Tiffany O Paulisch
- Westfälische Wilhelms-Universität Münster , Organisch-Chemisches Institut , Corrensstraße 40 , 48149 Münster , Germany .
| | - Felix Strieth-Kalthoff
- Westfälische Wilhelms-Universität Münster , Organisch-Chemisches Institut , Corrensstraße 40 , 48149 Münster , Germany .
| | - Christian Henkel
- Friedrich-Alexander-Universität Erlangen-Nürnberg , Department of Chemistry and Pharmacy , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Lena Pitzer
- Westfälische Wilhelms-Universität Münster , Organisch-Chemisches Institut , Corrensstraße 40 , 48149 Münster , Germany .
| | - Dirk M Guldi
- Friedrich-Alexander-Universität Erlangen-Nürnberg , Department of Chemistry and Pharmacy , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Frank Glorius
- Westfälische Wilhelms-Universität Münster , Organisch-Chemisches Institut , Corrensstraße 40 , 48149 Münster , Germany .
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23
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Saqib M, Bashir S, Kitte SA, Li H, Jin Y. High-efficiency cathodic electrochemiluminescence of the tris(2,2′-bipyridine)ruthenium(ii)/N-hydroxy compound system and its use for sensitive “turn-on” detection of mercury(ii) and methyl blue. Chem Commun (Camb) 2020; 56:1827-1830. [DOI: 10.1039/c9cc09973e] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
N-Hydroxysuccinimide (NHS) and N-hydroxysulfosuccinimide (NHSS) were exploited as efficient coreactants for cathodic Ru(bpy)32+ electrochemiluminescence (ECL) in neutral medium.
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Affiliation(s)
- Muhammad Saqib
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Shahida Bashir
- Faculty of Science
- Department of Mathematics
- University of Gujrat
- Gujrat 50700
- Pakistan
| | - Shimeles Addisu Kitte
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Haijuan Li
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
| | - Yongdong Jin
- State Key Laboratory of Electroanalytical Chemistry
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
- P. R. China
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24
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Tripathi KN, Belal M, Singh RP. Organo Photoinduced Decarboxylative Alkylation of Coumarins with N-(Acyloxy)phthalimide. J Org Chem 2019; 85:1193-1201. [DOI: 10.1021/acs.joc.9b00977] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Krishna N. Tripathi
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Md. Belal
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Ravi P. Singh
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
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25
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Wang C, Yu Y, Liu WL, Duan WL. Site-Tunable Csp3–H Bonds Functionalization by Visible-Light-Induced Radical Translocation of N-Alkoxyphthalimides. Org Lett 2019; 21:9147-9152. [DOI: 10.1021/acs.orglett.9b03524] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Chuanyong Wang
- College of Chemistry and Chemical Engineering, Yangzhou University, 180 Siwangting Road, Yangzhou 225002, China
| | - Yangyang Yu
- College of Chemistry and Chemical Engineering, Yangzhou University, 180 Siwangting Road, Yangzhou 225002, China
| | - Wen-Long Liu
- College of Chemistry and Chemical Engineering, Yangzhou University, 180 Siwangting Road, Yangzhou 225002, China
| | - Wei-Liang Duan
- College of Chemistry and Chemical Engineering, Yangzhou University, 180 Siwangting Road, Yangzhou 225002, China
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26
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Gryaznova TV, Kholin KV, Nikanshina EO, Khrizanforova VV, Strekalova SO, Fayzullin RR, Budnikova YH. Copper or Silver-Mediated Oxidative C(sp2)–H/N–H Cross-Coupling of Phthalimide and Heterocyclic Arenes: Access to N-Arylphthalimides. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00443] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Tatyana V. Gryaznova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
| | - Kirill V. Kholin
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
| | - Elizaveta O. Nikanshina
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
| | - Vera V. Khrizanforova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
| | - Sofia O. Strekalova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
| | - Robert R. Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
| | - Yulia H. Budnikova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str. 8, Kazan 420088, Russian Federation
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27
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Syroeshkin MA, Kuriakose F, Saverina EA, Timofeeva VA, Egorov MP, Alabugin IV. Hochkonversion von Reduktionsmitteln. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201807247] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Mikhail A. Syroeshkin
- N. D. Zelinsky Institute of Organic Chemistry Leninskyprosp. 47 119991 Moskau Russland
| | - Febin Kuriakose
- Department of Chemistry and Biochemistry Florida State University Tallahassee FL USA
| | - Evgeniya A. Saverina
- N. D. Zelinsky Institute of Organic Chemistry Leninskyprosp. 47 119991 Moskau Russland
- UMR CNRS 6226 ISCR University of Rennes 1 Rennes Frankreich
| | | | - Mikhail P. Egorov
- N. D. Zelinsky Institute of Organic Chemistry Leninskyprosp. 47 119991 Moskau Russland
| | - Igor V. Alabugin
- Department of Chemistry and Biochemistry Florida State University Tallahassee FL USA
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28
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Syroeshkin MA, Kuriakose F, Saverina EA, Timofeeva VA, Egorov MP, Alabugin IV. Upconversion of Reductants. Angew Chem Int Ed Engl 2019; 58:5532-5550. [DOI: 10.1002/anie.201807247] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Mikhail A. Syroeshkin
- N. D. Zelinsky Institute of Organic Chemistry Leninsky prosp. 47 119991 Moscow Russia
| | - Febin Kuriakose
- Department of Chemistry and Biochemistry Florida State University Tallahassee FL USA
| | - Evgeniya A. Saverina
- N. D. Zelinsky Institute of Organic Chemistry Leninsky prosp. 47 119991 Moscow Russia
- UMR CNRS 6226 ISCR University of Rennes 1 Rennes France
| | | | - Mikhail P. Egorov
- N. D. Zelinsky Institute of Organic Chemistry Leninsky prosp. 47 119991 Moscow Russia
| | - Igor V. Alabugin
- Department of Chemistry and Biochemistry Florida State University Tallahassee FL USA
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29
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Capaldo L, Ravelli D. Alkoxy radicals generation: facile photocatalytic reduction of N-alkoxyazinium or azolium salts. Chem Commun (Camb) 2019; 55:3029-3032. [DOI: 10.1039/c9cc00035f] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The photocatalytic reduction of N-alkoxyazinium or azolium salts allowed the facile generation of alkoxy radicals to be exploited in synthesis.
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Affiliation(s)
- Luca Capaldo
- PhotoGreen Lab, Department of Chemistry, University of Pavia
- 27100 Pavia
- Italy
| | - Davide Ravelli
- PhotoGreen Lab, Department of Chemistry, University of Pavia
- 27100 Pavia
- Italy
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30
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Affiliation(s)
- Sandip Murarka
- Department of Chemistry; Indian Institute of Technology Jodhpur; NH-65 Nagaur Road, Karwar - 342037 Jodhpur District, Rajasthan India
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31
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Evoniuk CJ, Gomes GDP, Hill SP, Fujita S, Hanson K, Alabugin IV. Coupling N–H Deprotonation, C–H Activation, and Oxidation: Metal-Free C(sp3)–H Aminations with Unprotected Anilines. J Am Chem Soc 2017; 139:16210-16221. [DOI: 10.1021/jacs.7b07519] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | | | - Sean P. Hill
- Florida State University, Tallahassee, Florida 32306, United States
| | - Satoshi Fujita
- Interdisciplinary
Graduate School of Engineering Sciences, Kyushu University, Fukuoka, Fukuoka Prefecture 819-0395, Japan
| | - Kenneth Hanson
- Florida State University, Tallahassee, Florida 32306, United States
| | - Igor V. Alabugin
- Florida State University, Tallahassee, Florida 32306, United States
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