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Potlitz F, Palm GJ, Bodtke A, Lammers M, Schade D, Link A. A Novel C3/ C4-Fused Indole Scaffold through Acid-Catalyzed Cascade Reaction. Molecules 2024; 29:3064. [PMID: 38999014 DOI: 10.3390/molecules29133064] [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: 05/30/2024] [Revised: 06/20/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024] Open
Abstract
3,4-bridged indoles are underrepresented among the vast number of indoles described in the literature. Attempts to access 3,4-macrocyclized indoles led to the unexpected formation of a novel tetracyclic indole through intramolecular acid-catalyzed ring contraction. The herein-established one-step synthetic route provides an excellent medicinal chemistry platform for the construction of screening libraries covering a unique chemical space of indoles.
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Affiliation(s)
- Felix Potlitz
- Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Gottfried J Palm
- Institute of Biochemistry, University of Greifswald, 17489 Greifswald, Germany
| | - Anja Bodtke
- Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Michael Lammers
- Institute of Biochemistry, University of Greifswald, 17489 Greifswald, Germany
| | - Dennis Schade
- Institute of Pharmacy, Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
- Partner Site Kiel, DZHK, German Center for Cardiovascular Research, 24105 Kiel, Germany
| | - Andreas Link
- Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
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2
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Abstract
Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N-O•. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N═O+) or reduced to anions (R1R2N-O-), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C-O bonds, allowing for the thermal generation of C radicals through reversible C-O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.
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Affiliation(s)
- Dirk Leifert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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3
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Lee W, Kim D, Seo S, Chang S. Photoinduced α-C-H Amination of Cyclic Amine Scaffolds Enabled by Polar-Radical Relay. Angew Chem Int Ed Engl 2022; 61:e202202971. [PMID: 35403797 DOI: 10.1002/anie.202202971] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Indexed: 11/09/2022]
Abstract
Herein, we report a polar-radical relay strategy for α-C-H amination of cyclic amines with N-chloro-N-sodio-carbamates. The relay is initiated by in situ generation of cyclic iminium intermediate using N-iodosuccinimide (NIS) oxidant as an initiator, which then operates through a series of polar (addition and elimination) and radical (homolysis, hydrogen- and halogen atom transfer) reactions to enable the challenging C-N bond formation in a controlled manner. A broad range of α-amino cyclic amines were readily accessed with excellent regioselectivity, and the superb applicability was further demonstrated by functionalization of biologically relevant compounds.
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Affiliation(s)
- Wongyu Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Dongwook Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Sangwon Seo
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Sukbok Chang
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
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4
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Miller JL, Lawrence JMIA, Rodriguez Del Rey FO, Floreancig PE. Synthetic applications of hydride abstraction reactions by organic oxidants. Chem Soc Rev 2022; 51:5660-5690. [PMID: 35712818 DOI: 10.1039/d1cs01169c] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Carbon-hydrogen bond functionalizations provide an attractive method for streamlining organic synthesis, and many strategies have been developed for conducting these transformations. Hydride-abstracting reactions have emerged as extremely effective methods for oxidative bond-forming processes due to their mild reaction conditions and high chemoselectivity. This review will predominantly focus on the mechanism, reaction development, natural product synthesis applications, approaches to catalysis, and use in enantioselective processes for hydride abstractions by quinone, oxoammonium ion, and carbocation oxidants. These are the most commonly employed hydride-abstracting agents, but recent efforts illustrate the potential for weaker ketone and triaryl borane oxidants, which will be covered at the end of the review.
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Affiliation(s)
- Jenna L Miller
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260, USA.
| | - Jean-Marc I A Lawrence
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260, USA.
| | | | - Paul E Floreancig
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260, USA.
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5
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Lee W, Kim D, Seo S, Chang S. Photoinduced α‐C−H Amination of Cyclic Amine Scaffolds Enabled by Polar‐Radical Relay. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202971] [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)
- Wongyu Lee
- Department of Chemistry Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations Institute for Basic Science (IBS) Daejeon 34141 Republic of Korea
| | - Dongwook Kim
- Department of Chemistry Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations Institute for Basic Science (IBS) Daejeon 34141 Republic of Korea
| | - Sangwon Seo
- Department of Chemistry Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations Institute for Basic Science (IBS) Daejeon 34141 Republic of Korea
| | - Sukbok Chang
- Department of Chemistry Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations Institute for Basic Science (IBS) Daejeon 34141 Republic of Korea
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6
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Lohmann N, Milovanović V, Piekarski DG, García Mancheño O. Metal-free oxoammonium salt-mediated C(sp 3)-H oxidative Ugi-azide multicomponent reaction. Org Biomol Chem 2022; 20:2896-2908. [PMID: 35319061 DOI: 10.1039/d2ob00101b] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In this work, an efficient oxidative C(sp3)-H Ugi-azide multicomponent reaction of cyclic benzylic amines to the corresponding α-tetrazolo compounds using a TEMPO salt as mild hydride abstractor-type oxidant is reported. This simple one-pot approach allows the direct functionalization of N-heterocycles such as tetrahydroisoquinolines with a variety of isocyanides and NaN3 as a practical azide source. The reaction proceeds at room temperature and without the need of acid additives, allowing for the use of sensitive substrates, while minimizing isocyanide polymerization to provide the desired heterocycle-tetrazole products in synthetically useful yields (up to 99%).
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Affiliation(s)
- Niklas Lohmann
- University of Münster, Organic Chemistry Institute, Corrensstraße 40, 48149 Münster, Germany.
| | - Vesna Milovanović
- University of Münster, Organic Chemistry Institute, Corrensstraße 40, 48149 Münster, Germany. .,University of Kragujevac, Faculty of Agronomy, Department of Chemistry and Chemical Engineering, Cara Dušana 34, 32000 Čačak, Serbia
| | - Dariusz G Piekarski
- Polish Academy of Sciences, Institute of Physical Chemistry, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Olga García Mancheño
- University of Münster, Organic Chemistry Institute, Corrensstraße 40, 48149 Münster, Germany.
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7
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Robert EGL, Le Du E, Waser J. Synthesis of Polycyclic Aminal Heterocycles via Decarboxylative Cyclisation of Dipeptide Derivatives. Chem Commun (Camb) 2022; 58:3473-3476. [DOI: 10.1039/d2cc00167e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An oxidative-decarboxylative intramolecular cyclisation of dipeptide derivatives is reported. This transformation is promoted by phenyl iodine (III) diacetate (PIDA) in combination with BF3·OEt2. The reaction gives access to a variety...
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8
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Iwabuchi Y, Nagasawa S. The Utility of Oxoammonium Species in Organic Synthesis: Beyond Alcohol Oxidation. HETEROCYCLES 2022. [DOI: 10.3987/rev-21-sr(r)2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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Singh P. Synthetic Approaches Towards the Synthesis of C-1 Azole Substituted Tetrahydroisoquinolines. CURR ORG CHEM 2021. [DOI: 10.2174/1385272824999201228140959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
C-1 substituted tetrahydroisoquinolines have emerged as important scaffolds in
pharmaceutical and medical research. Although various methods for α-substitution on tetrahydroisoquinolines
have been discovered, the introduction of the azole group at C-1 position
remains a challenge. Recently, direct C-H activation methods and multicomponent reactions
have been employed towards the synthesis of azole containing tetrahydroisoquinolines. A
summary of such synthetic strategies is presented here as these promising methods can help
in developing more efficient synthetic routes. This minireview covers the available synthetic
methods and their mechanistic pathways for the preparation of C-1 azole substituted tetrahydroisoquinolines.
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Affiliation(s)
- Pushpinder Singh
- Department of Chemistry, DAV University, Jalandhar, Punjab, 144012, India
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10
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Affiliation(s)
- Paramasivam Sivaguru
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Northeast Normal University, Changchun 130024, China
| | - Yongquan Ning
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Northeast Normal University, Changchun 130024, China
| | - Xihe Bi
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Northeast Normal University, Changchun 130024, China
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Elliott Q, Dos Passos Gomes G, Evoniuk CJ, Alabugin IV. Testing the limits of radical-anionic CH-amination: a 10-million-fold decrease in basicity opens a new path to hydroxyisoindolines via a mixed C-N/C-O-forming cascade. Chem Sci 2020; 11:6539-6555. [PMID: 34094120 PMCID: PMC8159354 DOI: 10.1039/c9sc06511c] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 02/14/2020] [Indexed: 11/21/2022] Open
Abstract
An intramolecular C(sp3)-H amidation proceeds in the presence of t-BuOK, molecular oxygen, and DMF. This transformation is initiated by the deprotonation of an acidic N-H bond and selective radical activation of a benzylic C-H bond towards hydrogen atom transfer (HAT). Cyclization of this radical-anion intermediate en route to a two-centered/three-electron (2c,3e) C-N bond removes electron density from nitrogen. As this electronegative element resists such an "oxidation", making nitrogen more electron rich is key to overcoming this problem. This work dramatically expands the range of N-anions that can participate in this process by using amides instead of anilines. The resulting 107-fold decrease in the N-component basicity (and nucleophilicity) doubles the activation barrier for C-N bond formation and makes this process nearly thermoneutral. Remarkably, this reaction also converts a weak reductant into a much stronger reductant. Such "reductant upconversion" allows mild oxidants like molecular oxygen to complete the first part of the cascade. In contrast, the second stage of NH/CH activation forms a highly stabilized radical-anion intermediate incapable of undergoing electron transfer to oxygen. Because the oxidation is unfavored, an alternative reaction path opens via coupling between the radical anion intermediate and either superoxide or hydroperoxide radical. The hydroperoxide intermediate transforms into the final hydroxyisoindoline products under basic conditions. The use of TEMPO as an additive was found to activate less reactive amides. The combination of experimental and computational data outlines a conceptually new mechanism for conversion of unprotected amides into hydroxyisoindolines proceeding as a sequence of C-H amidation and C-H oxidation.
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Affiliation(s)
- Quintin Elliott
- Department of Chemistry and Biochemistry, Florida State University Tallahassee Florida 32306 USA
| | - Gabriel Dos Passos Gomes
- Department of Chemistry and Biochemistry, Florida State University Tallahassee Florida 32306 USA
| | - Christopher J Evoniuk
- Department of Chemistry and Biochemistry, Florida State University Tallahassee Florida 32306 USA
| | - Igor V Alabugin
- Department of Chemistry and Biochemistry, Florida State University Tallahassee Florida 32306 USA
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12
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Huang L, Xun X, Zhao M, Xue J, Li G, Hong L. Copper-Catalyzed Regioselective sp3 C–H Azidation of Alkyl Substituents of Indoles and Tetrahydrocarbazoles. J Org Chem 2019; 84:11885-11890. [DOI: 10.1021/acs.joc.9b01742] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Liwu Huang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Xudong Xun
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Man Zhao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Jianzhong Xue
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Guofeng Li
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Liang Hong
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
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13
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Dascalu AE, Ghinet A, Lipka E, Collinet M, Rigo B, Billamboz M. Cesium salts as superior catalysts for solvent-free modifications of biosourced pterolactam. MOLECULAR CATALYSIS 2019. [DOI: 10.1016/j.mcat.2019.03.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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14
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He Y, Zheng Z, Liu Y, Qiao J, Zhang X, Fan X. Selective Cleavage and Tunable Functionalization of the C–C/C–N Bonds of N-Arylpiperidines Promoted by tBuONO. Org Lett 2019; 21:1676-1680. [DOI: 10.1021/acs.orglett.9b00226] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yan He
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory for Yellow River and Huai River Water Environmental Pollution Control, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Environment, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Zhi Zheng
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory for Yellow River and Huai River Water Environmental Pollution Control, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Environment, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Yajie Liu
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory for Yellow River and Huai River Water Environmental Pollution Control, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Environment, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Jiajie Qiao
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory for Yellow River and Huai River Water Environmental Pollution Control, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Environment, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Xinying Zhang
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory for Yellow River and Huai River Water Environmental Pollution Control, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Environment, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Xuesen Fan
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Key Laboratory for Yellow River and Huai River Water Environmental Pollution Control, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Environment, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
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Brandhofer T, Özdemir A, Gini A, Mancheño OG. Double Cu‐Catalyzed Direct Csp3−H Azidation/CuAAC Reaction: A Direct Approach towards Demanding Triazole Conjugates. Chemistry 2019; 25:4077-4086. [DOI: 10.1002/chem.201806288] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/21/2019] [Indexed: 12/30/2022]
Affiliation(s)
- Tobias Brandhofer
- Organic Chemistry InstituteMünster University Corrensstr. 40 48149 Münster Germany
- Organic Chemistry InstituteRegensburg University Universitätstr. 31 93053 Regensburg Germany
| | - Aysegül Özdemir
- Organic Chemistry InstituteRegensburg University Universitätstr. 31 93053 Regensburg Germany
| | - Andrea Gini
- Organic Chemistry InstituteRegensburg University Universitätstr. 31 93053 Regensburg Germany
| | - Olga García Mancheño
- Organic Chemistry InstituteMünster University Corrensstr. 40 48149 Münster Germany
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Sun R, Yang X, Chen X, Zhang C, Zhao X, Wang X, Zheng X, Yuan M, Fu H, Li R, Chen H. Rh(III)-Catalyzed [4 + 2] Self-Annulation of N-Vinylarylamides. Org Lett 2018; 20:6755-6759. [PMID: 30346794 DOI: 10.1021/acs.orglett.8b02872] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An efficient rhodium(III)-catalyzed self-annulation of N-vinylarylamide has been developed. This reaction features a simple system and good reactivity with complete regioselectivity. The protocol provides easy access to an aminal incorporated dihydroisoquinolinone, which proved to be a versatile synthetic synthon. The kinetic isotope effect experiments showed that C-H activation is the rate-limiting step, and competition studies revealed the annulation exhibits a strong self-recognition mode. In addition, a seven-membered rhodacycle species was isolated and established as the key reaction intermediate.
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Affiliation(s)
- Rui Sun
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Xiao Yang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Xue Chen
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Chunchun Zhang
- Analytical & Testing Center , Sichuan University , Chengdu , Sichuan 610064 , P. R. China
| | - Xiaoyu Zhao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Xin Wang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Xueli Zheng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Maolin Yuan
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Haiyan Fu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Ruixiang Li
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
| | - Hua Chen
- Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry , Sichuan University Chengdu 610064 , P. R. China
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