1
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Novaes LFT, Ho JSK, Mao K, Villemure E, Terrett JA, Lin S. α,β-Desaturation and Formal β-C(sp 3)-H Fluorination of N-Substituted Amines: A Late-Stage Functionalization Strategy Enabled by Electrochemistry. J Am Chem Soc 2024; 146:22982-22992. [PMID: 39132893 PMCID: PMC11366977 DOI: 10.1021/jacs.4c02548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Incorporation of C(sp3)-F bonds in biologically active compounds is a common strategy employed in medicinal and agricultural chemistry to tune pharmacokinetic and pharmacodynamic properties. Due to the limited number of robust strategies for C(sp3)-H fluorination of complex molecules, time-consuming de novo syntheses of such fluorinated analogs are typically required, representing a major bottleneck in the drug discovery process. In this work, we present a general and operationally simple strategy for site-specific β-C(sp3)-H fluorination of amine derivatives including carbamates, amides, and sulfonamides, which is compatible with a wide range of functional groups including N-heteroarenes. In this approach, an improved electrochemical Shono oxidation is used to set the site of functionalization via net α,β-desaturation to access enamine derivatives. We further developed a series of new transformations of these enamine intermediates to synthesize a variety of β-fluoro-α-functionalized structures, allowing efficient access to pertinent targets to accelerate drug discovery campaigns.
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Affiliation(s)
- Luiz F T Novaes
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Justin S K Ho
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Kaining Mao
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Elisia Villemure
- Department of Discovery Chemistry, Genentech, Inc., South San Francisco, California 94080, United States
| | - Jack A Terrett
- Department of Discovery Chemistry, Genentech, Inc., South San Francisco, California 94080, United States
| | - Song Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
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2
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Giannessi L, Longo M, Massera C, Radi M. Late-stage functionalization of the 4-amino-2-pyridone chemotype using electrochemical and MCR approaches. Chem Commun (Camb) 2024. [PMID: 39139069 DOI: 10.1039/d4cc02473g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
We report the development and application of different strategies for the late-stage functionalization (LSF) of the biologically relevant 4-amino-2-pyridone chemotype. Using the recently discovered PCSK9 inhibitor 5c as a prototype, a series of electrochemical LSF (e-LSF) and multicomponent LSF (MCR-LSF) have been set-up to decorate the 4-amino-2-pyridone scaffold. The usefulness of these methods has been demonstrated by generating a series of novel derivatives in a site-selective and sustainable way.
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Affiliation(s)
- Lisa Giannessi
- Dipartimento di Scienze degli Alimenti e del Farmaco (DipALIFAR), Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy.
| | - Matteo Longo
- Dipartimento di Scienze degli Alimenti e del Farmaco (DipALIFAR), Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy.
| | - Chiara Massera
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università degli Studi di Parma, Viale delle Scienze 17/A, Parma, 43124, Italy
| | - Marco Radi
- Dipartimento di Scienze degli Alimenti e del Farmaco (DipALIFAR), Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy.
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3
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Fang X, Zeng Y, Huang Y, Zhu Z, Lin S, Xu W, Zheng C, Hu X, Qiu Y, Ruan Z. Electrochemical synthesis of peptide aldehydes via C‒N bond cleavage of cyclic amines. Nat Commun 2024; 15:5181. [PMID: 38890290 PMCID: PMC11189564 DOI: 10.1038/s41467-024-49223-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 05/29/2024] [Indexed: 06/20/2024] Open
Abstract
Peptide aldehydes are crucial biomolecules essential to various biological systems, driving a continuous demand for efficient synthesis methods. Herein, we develop a metal-free, facile, and biocompatible strategy for direct electrochemical synthesis of unnatural peptide aldehydes. This electro-oxidative approach enabled a step- and atom-economical ring-opening via C‒N bond cleavage, allowing for homoproline-specific peptide diversification and expansion of substrate scope to include amides, esters, and cyclic amines of various sizes. The remarkable efficacy of the electro-synthetic protocol set the stage for the efficient modification and assembly of linear and macrocyclic peptides using a concise synthetic sequence with racemization-free conditions. Moreover, the combination of experiments and density functional theory (DFT) calculations indicates that different N-acyl groups play a decisive role in the reaction activity.
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Affiliation(s)
- Xinyue Fang
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China
| | - Yong Zeng
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China
| | - Yawen Huang
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China
| | - Zile Zhu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, PR China
| | - Shengsheng Lin
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China
| | - Wenyan Xu
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China
| | - Chengwei Zheng
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China
| | - Xinwei Hu
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China.
| | - Youai Qiu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, PR China.
| | - Zhixiong Ruan
- Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, PR China.
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4
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Lian F, Li JL, Xu K. When transition-metal catalysis meets electrosynthesis: a recent update. Org Biomol Chem 2024; 22:4390-4419. [PMID: 38771266 DOI: 10.1039/d4ob00484a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
While aiming at sustainable synthesis, organic electrosynthesis has attracted increasing attention in the past few years. In parallel, with a deeper understanding of catalyst and ligand design, 3d transition-metal catalysis allows the conception of more straightforward synthetic routes in a cost-effective fashion. Owing to their intrinsic advantages, the merger of organic electrosynthesis with 3d transition-metal catalysis has offered huge opportunities for conceptually novel transformations while limiting ecological footprint. This review summarizes the key advancements in this direction published in the recent two years, with specific focus placed on strategy design and mechanistic aspects.
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Affiliation(s)
- Fei Lian
- School of Medicine, Henan Engineering Research Center of Funiu Mountain's Medicinal Resources Utilization and Molecular Medicine, Pingdingshan University, Pingdingshan 467000, China.
| | - Jiu-Ling Li
- School of Medicine, Henan Engineering Research Center of Funiu Mountain's Medicinal Resources Utilization and Molecular Medicine, Pingdingshan University, Pingdingshan 467000, China.
| | - Kun Xu
- College of Chemistry and Life Science, Beijing University of Technology, Beijing 100124, China.
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5
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Krajczy P, Meyners C, Repity ML, Hausch F. Structure-Based Design of Ultrapotent Tricyclic Ligands for FK506-Binding Proteins. Chemistry 2024:e202401405. [PMID: 38837733 DOI: 10.1002/chem.202401405] [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: 04/10/2024] [Revised: 05/28/2024] [Accepted: 06/05/2024] [Indexed: 06/07/2024]
Abstract
Access to small, rigid, and sp3-rich molecules is a major limitation in the drug discovery for challenging protein targets. FK506-binding proteins hold high potential as drug targets or enablers of molecular glues but are fastidious in the chemotypes accepted as ligands. We here report an enantioselective synthesis of a highly rigidified pipecolate-mimicking tricyclic scaffold that precisely positions functional groups for interacting with FKBPs. This was enabled by a 14-step gram-scale synthesis featuring anodic oxidation, stereospecific vinylation, and N-acyl iminium cyclization. Structure-based optimization resulted in the discovery of FKBP inhibitors with picomolar biochemical and subnanomolar cellular activity that represent the most potent FKBP ligands known to date.
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Affiliation(s)
- Patryk Krajczy
- Institute for Organic Chemistry and Biochemistry, Technical University Darmstadt, Peter-Grünberg-Straße 4, Darmstadt, 64287, Germany
| | - Christian Meyners
- Institute for Organic Chemistry and Biochemistry, Technical University Darmstadt, Peter-Grünberg-Straße 4, Darmstadt, 64287, Germany
| | - Maximilian L Repity
- Institute for Organic Chemistry and Biochemistry, Technical University Darmstadt, Peter-Grünberg-Straße 4, Darmstadt, 64287, Germany
| | - Felix Hausch
- Institute for Organic Chemistry and Biochemistry, Technical University Darmstadt, Peter-Grünberg-Straße 4, Darmstadt, 64287, Germany
- Centre for Synthetic Biology, Technical University of Darmstadt, Darmstadt, 64283, Germany
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6
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Smith BP, Truax NJ, Pollatos AS, Meanwell M, Bedekar P, Garrido-Castro AF, Baran PS. Total Synthesis of Dragocins A-C through Electrochemical Cyclization. Angew Chem Int Ed Engl 2024; 63:e202401107. [PMID: 38358802 DOI: 10.1002/anie.202401107] [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: 01/16/2024] [Revised: 02/14/2024] [Accepted: 02/15/2024] [Indexed: 02/16/2024]
Abstract
The first total synthesis of dragocins A-C, remarkable natural products containing an unusual C4' oxidized ribose architecture bridged by a polyhydroxylated pyrrolidine, is presented through a route featuring a number of uncommon maneuvers. Several generations towards the target molecules are presented, including the spectacular failure of a key C-H oxidation on a late-stage intermediate. The final route features rapid, stereocontrolled access to a densely functionalized pyrrolidine and an unprecedented diastereoselective oxidative electrochemical cyclization to forge the hallmark 9-membered ring. Preliminary studies suggest this electrochemical oxidation protocol is generally useful.
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Affiliation(s)
- Brendyn P Smith
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Nathanyal J Truax
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Alexandros S Pollatos
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Michael Meanwell
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr NW, Edmonton, AB T6G 2N4, Canada
| | - Pranali Bedekar
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
| | - Alberto F Garrido-Castro
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
- Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093, Zürich, Switzerland
| | - Phil S Baran
- Department of Chemistry, Scripps Research, 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
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7
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Miller JL, Damodaran K, Floreancig PE. Nitrogen Heterocycle Synthesis through Hydride Abstraction of Acyclic Carbamates and Related Species: Scope, Mechanism, Stereoselectivity, and Product Conformation Studies. Chemistry 2023; 29:e202302977. [PMID: 37796745 DOI: 10.1002/chem.202302977] [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: 09/13/2023] [Revised: 10/04/2023] [Accepted: 10/05/2023] [Indexed: 10/07/2023]
Abstract
Acyliminium ions and related species are potent electrophiles that can be quite valuable in the synthesis of nitrogen-containing molecules. This manuscript describes a protocol to form these intermediates through hydride abstractions of easily accessible allylic carbamates, amides, and sulfonamides that avoids the reversibility that is possible in classical condensation-based routes. These intermediates are used in the preparation of a range of nitrogen-containing heterocycles, and in many cases high levels of stereocontrol are observed. Specifically areas of investigation include the impact of chemical structure on oxidation efficiency, the geometry of the intermediate iminium ions, the impact of a substrate stereocenter on stereocontrol, and an examination of transition state geometry.
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Affiliation(s)
- Jenna L Miller
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260, USA
| | - Krishnan Damodaran
- 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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8
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Rein J, Zacate SB, Mao K, Lin S. A tutorial on asymmetric electrocatalysis. Chem Soc Rev 2023; 52:8106-8125. [PMID: 37910160 PMCID: PMC10842033 DOI: 10.1039/d3cs00511a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Electrochemistry has emerged as a powerful means to enable redox transformations in modern chemical synthesis. This tutorial review delves into the unique advantages of electrochemistry in the context of asymmetric catalysis. While electrochemistry has historically been used as a green and mild alternative for established enantioselective transformations, in recent years asymmetric electrocatalysis has been increasingly employed in the discovery of novel asymmetric methodologies based on reaction mechanisms unique to electrochemistry. This tutorial review first provides a brief tutorial introduction to electrosynthesis, then explores case studies on homogenous small molecule asymmetric electrocatalysis. Each case study serves to highlight a key advance in the field, starting with the historic electrification of known asymmetric transformations and culminating with modern methods relying on unique electrochemical mechanistic sequences. Finally, we highlight case studies in the emerging reasearch areas at the interface of asymmetric electrocatalysis with biocatalysis and heterogeneous catalysis.
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Affiliation(s)
- Jonas Rein
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Samson B Zacate
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Kaining Mao
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Song Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.
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9
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Bai J, Bao M, Wang S, Wen T, Li Y, Zhang J, Mei T, Guo Y. Insights into electrogenerated intermediates and rapid screening of electrochemical reactions by surface-modified carbon fiber paper redox spray ionization mass spectrometry. Anal Chim Acta 2023; 1279:341794. [PMID: 37827687 DOI: 10.1016/j.aca.2023.341794] [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: 06/06/2023] [Revised: 08/29/2023] [Accepted: 09/06/2023] [Indexed: 10/14/2023]
Abstract
The combination of electrochemistry and mass spectrometry is a powerful analytical tool for studying redox reaction mechanisms and identifying products or intermediates. However, the previously reported devices all require bespoke fabrication and are too complicated to be assembled and used by others. Crucially, the long ion transport distance and small spray volumes make it difficult to capture the short-lived intermediates. We present a practical mass spectrometric method in which surface-modified carbon fiber paper is innovatively applied to detect electrogenerated intermediates. Treating carbon fiber paper with dilute nitric acid removes its surface impurities, enhancing the capability of electro-redox. Electrospray ionization and redox reaction occur simultaneously on the tip of the paper. Transient electro-redox species generate and transfer into gas phase as soon as the appearance of spray. Rapid transport of quantities of electrogenerated ions to the mass spectrometer inlet makes it possible for mass spectrometric identification on the millisecond scale. The short-lived radical cations and iminium ions were successfully captured, reflecting the starting step of the cross-dehydrogenation coupling reaction. The real-time oxidation and online functionalization reactions of tertiary amines were achieved using this device without additional oxidants and electrolytes. In this way we could achieve in-depth mechanistic understanding and rapid screening of serial reactions.
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Affiliation(s)
- Jiahui Bai
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Mingmai Bao
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Shanshan Wang
- College of Science, Chang'an University, Xi'an, 710064, China
| | - Tianlun Wen
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Yuling Li
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jing Zhang
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
| | - Tiansheng Mei
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
| | - Yinlong Guo
- State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
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10
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Wang Y, Dana S, Long H, Xu Y, Li Y, Kaplaneris N, Ackermann L. Electrochemical Late-Stage Functionalization. Chem Rev 2023; 123:11269-11335. [PMID: 37751573 PMCID: PMC10571048 DOI: 10.1021/acs.chemrev.3c00158] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Indexed: 09/28/2023]
Abstract
Late-stage functionalization (LSF) constitutes a powerful strategy for the assembly or diversification of novel molecular entities with improved physicochemical or biological activities. LSF can thus greatly accelerate the development of medicinally relevant compounds, crop protecting agents, and functional materials. Electrochemical molecular synthesis has emerged as an environmentally friendly platform for the transformation of organic compounds. Over the past decade, electrochemical late-stage functionalization (eLSF) has gained major momentum, which is summarized herein up to February 2023.
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Affiliation(s)
| | | | | | - Yang Xu
- Institut für Organische
und Biomolekulare Chemie and Wöhler Research Institute for
Sustainable Chemistry (WISCh), Georg-August-Universität, Göttingen 37077, Germany
| | - Yanjun Li
- Institut für Organische
und Biomolekulare Chemie and Wöhler Research Institute for
Sustainable Chemistry (WISCh), Georg-August-Universität, Göttingen 37077, Germany
| | - Nikolaos Kaplaneris
- Institut für Organische
und Biomolekulare Chemie and Wöhler Research Institute for
Sustainable Chemistry (WISCh), Georg-August-Universität, Göttingen 37077, Germany
| | - Lutz Ackermann
- Institut für Organische
und Biomolekulare Chemie and Wöhler Research Institute for
Sustainable Chemistry (WISCh), Georg-August-Universität, Göttingen 37077, Germany
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11
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Chang Z, Wang S, Huang J, Chen G, Tang Z, Wang R, Zhao D. Copper catalyzed Shono-type oxidation of proline residues in peptide. SCIENCE ADVANCES 2023; 9:eadj3090. [PMID: 37703373 PMCID: PMC10881060 DOI: 10.1126/sciadv.adj3090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 08/11/2023] [Indexed: 09/15/2023]
Abstract
Since the initial report in 1975, the Shono oxidation has become a powerful tool to functionalize the α position of amines, including proline derivatives, by electrochemical oxidation. However, the application of electrochemical Shono oxidations is restricted to the preparation of simple building blocks and homogeneous Shono-type oxidation of proline derivatives remains challenging. The late-stage functionalization at proline residues embedded within peptides is highly important as substitutions about the proline ring are known to affect biological and pharmacological activities. Here, we show that homogenous copper-catalyzed oxidation conditions complement the Shono oxidation and this general protocol can be applied to a series of formal C-C coupling reactions with a variety of nucleophiles using a one-pot procedure. This protocol shows good tolerance toward 19 proteinogenic amino acids and was used to functionalize several representative bioactive peptides, including captopril, enalapril, Smac, and endomorphin-2. Last, peptide cyclization can also be achieved by using an appropriately positioned side-chain hydroxyl moiety.
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Affiliation(s)
- Zhe Chang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Si Wang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jialin Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Geshuyi Chen
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Zhanyong Tang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Rui Wang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Depeng Zhao
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
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12
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Hatch CE, Chain WJ. Electrochemically Enabled Total Syntheses of Natural Products. ChemElectroChem 2023; 10:e202300140. [PMID: 38106361 PMCID: PMC10723087 DOI: 10.1002/celc.202300140] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Indexed: 12/19/2023]
Abstract
Electrochemical techniques have helped to enable the total synthesis of natural products since the pioneering work of Kolbe in the mid 1800's. The electrochemical toolset grows every day and these new possibilities change the way chemists look at and think about natural products. This review provides a perspective on total syntheses wherein electrochemical techniques enabled the carbon─carbon bond formations in the skeletal assembly of important natural products, discussion of mechanistic details, and representative examples of the bond formations enabled over the last several decades. These bond formations are often distinctly different from those possible with conventional chemistries and allow assemblies complementary to other techniques.
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Affiliation(s)
- Chad E Hatch
- Chemical Biology, Memorial Sloan Kettering Cancer Center, 417 E. 68 St., New York, NY, 10065 (United States)
| | - William J Chain
- Department of Chemistry & Biochemistry, University of Delaware, 163 The Green, Newark, DE, 19716 (United States)
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13
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He Z, Liu HL, Wang ZH, Jiao KJ, Li ZM, Li ZJ, Fang P, Mei TS. C(sp 3)-H Aerobic Alkenylation of Tetrahydroisoquinolines via Organic Electrosynthesis. J Org Chem 2023; 88:6203-6208. [PMID: 37058587 DOI: 10.1021/acs.joc.3c00223] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
A method for the C(sp3)-H alkenylation of N-aryl-tetrahydroisoquinoline (THIQ) has been developed by the combination of electrooxidation and a copper catalyst. The corresponding products were obtained with good to excellent yields under mild conditions. Besides, the addition of TEMPO as an electron mediator is crucial to this transformation, since the oxidative reaction could proceed under a low electrode potential. In addition, the catalytic asymmetric variant has also been demonstrated with good enantioselectivity.
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Affiliation(s)
- Zeng He
- College of Chemistry and Materials, Sichuan Normal University, Chengdu 610068, China
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Hui-Lin Liu
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zhen-Hua Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Ke-Jing Jiao
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zi-Meng Li
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zhang-Jian Li
- College of Chemistry and Materials, Sichuan Normal University, Chengdu 610068, China
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Ping Fang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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14
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Wang Y, Zhao R, Ackermann L. Electrochemical Syntheses of Polycyclic Aromatic Hydrocarbons (PAHs). ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2300760. [PMID: 36965124 DOI: 10.1002/adma.202300760] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/02/2023] [Indexed: 06/18/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) have surfaced as increasingly viable components in optoelectronics and material sciences. The development of highly efficient and atom-economic tools to prepare PAHs under exceedingly mild conditions constitutes a long-term goal. Traditional syntheses of PAHs have largely relied on multistep approaches or the conventional Scholl reaction. However, Scholl reactions are largely inefficient with electron-deficient substrates, require stoichiometric chemical oxidants, and typically occur in the presence of strong acid. In sharp contrast, electrochemistry has gained considerable momentum during the past decade as an alternative for the facile and straightforward PAHs assembly, generally via electro-oxidative dehydrogenative annulation, releasing molecular hydrogen as the sole stoichiometric byproduct by the hydrogen evolution reaction. This review provides an overview on the recent and significant advances in the field of electrochemical syntheses of various PAHs until January 2023.
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Affiliation(s)
- Yulei Wang
- Institut für Organische und Biomolekulare Chemie and Wöhler Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität Göttingen, Tammanstraße 2, 37077, Göttingen, Germany
| | - Rong Zhao
- Institut für Organische und Biomolekulare Chemie and Wöhler Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität Göttingen, Tammanstraße 2, 37077, Göttingen, Germany
| | - Lutz Ackermann
- Institut für Organische und Biomolekulare Chemie and Wöhler Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität Göttingen, Tammanstraße 2, 37077, Göttingen, Germany
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15
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Liu HL, He Z, Wang NN, Xu H, Fang P, Mei TS. C(sp 3)-H Alkenylation of Tetrahydroisoquinolines via Merging Electrochemistry and Organocatalysis. Org Lett 2023; 25:608-613. [PMID: 36695740 DOI: 10.1021/acs.orglett.2c04136] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
C(sp3)-H alkenylation of tetrahydroisoquinoline by merging Shono oxidation and the Morita-Baylis-Hillman reaction is developed, employing 4-dimethylaminopyridine as an organocatalyst and TEMPO/NaBr as an electrocatalyst. The reaction proceeds via the interception of an iminium cation intermediate, which is generated in situ from anodic oxidation, leading to aza-Morita-Baylis-Hillman reaction products. Additionally, the use of TEMPO and NaBr as mediators is crucial to avoid the decomposition of products by lowering the oxidation potential of the reaction.
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Affiliation(s)
- Hui-Lin Liu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P.R. China
| | - Zeng He
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P.R. China
| | - Na-Na Wang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P.R. China.,Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, P.R. China
| | - Hao Xu
- Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, P.R. China
| | - Ping Fang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P.R. China
| | - Tian-Sheng Mei
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P.R. China
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16
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Karipal Padinjare Veedu D, Connal LA, Malins LR. Tunable Electrochemical Peptide Modifications: Unlocking New Levels of Orthogonality for Side-Chain Functionalization. Angew Chem Int Ed Engl 2023; 62:e202215470. [PMID: 36336657 PMCID: PMC10107541 DOI: 10.1002/anie.202215470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 11/09/2022]
Abstract
Electrochemical transformations provide enticing opportunities for programmable, residue-specific peptide modifications. Herein, we harness the potential of amidic side-chains as underutilized handles for late-stage modification through the development of an electroauxiliary-assisted oxidation of glutamine residues within unprotected peptides. Glutamine building blocks bearing electroactive side-chain N,S-acetals are incorporated into peptides using standard Fmoc-SPPS. Anodic oxidation of the electroauxiliary in the presence of diverse alcohol nucleophiles enables the installation of high-value N,O-acetal functionalities. Proof-of-principle for an electrochemical peptide stapling protocol, as well as the functionalization of dynorphin B, an endogenous opioid peptide, demonstrates the applicability of the method to intricate peptide systems. Finally, the site-selective and tunable electrochemical modification of a peptide bearing two discretely oxidizable sites is achieved.
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Affiliation(s)
- Dhanya Karipal Padinjare Veedu
- Research School of ChemistryAustralian National UniversityCanberraACT 2601Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein ScienceAustralian National UniversityCanberraACT 2601Australia
| | - Luke A. Connal
- Research School of ChemistryAustralian National UniversityCanberraACT 2601Australia
| | - Lara R. Malins
- Research School of ChemistryAustralian National UniversityCanberraACT 2601Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein ScienceAustralian National UniversityCanberraACT 2601Australia
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17
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Mechanistic Aspects of the Electrochemical Oxidation of Aliphatic Amines and Aniline Derivatives. Molecules 2023; 28:molecules28020471. [PMID: 36677530 PMCID: PMC9864799 DOI: 10.3390/molecules28020471] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 12/30/2022] [Accepted: 01/01/2023] [Indexed: 01/05/2023] Open
Abstract
The electrochemical oxidation of amines is an essential alternative to the conventional chemical transformation that provides critical routes for synthesising and modifying a wide range of chemically useful molecules, including pharmaceuticals and agrochemicals. As a result, the anodic reactivity of these compounds has been extensively researched over the past seven decades. However, the different mechanistic aspects of the electrochemical oxidation of amines have never been discussed from a comprehensive and general point of view. This review examines the oxidation mechanism of aliphatic amines, amides, aniline and aniline derivatives, carbamates, and lactams, either directly oxidised at different electrode surfaces or indirectly oxidised by a reversible redox molecule, in which the reactive form was generated in situ. The mechanisms are compared and simplified to understand all possible pathways for the oxidation of amines using only a few general mechanisms. Examples of the application of these oxidation reactions are also provided.
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18
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Liang K, Zhang Q, Guo C. Nickel-catalyzed switchable asymmetric electrochemical functionalization of alkenes. SCIENCE ADVANCES 2022; 8:eadd7134. [PMID: 36351023 PMCID: PMC9645727 DOI: 10.1126/sciadv.add7134] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The development of general electrocatalytic methods for the diversity-oriented regio- and stereoselective functionalization of alkenes remains a challenge in organic synthesis. We present a switchable electrocatalytic method based on anodic oxidative activation for the controlled liberation of chiral α-keto radical species toward stereoselective organic transformations. Electrogenerated α-keto radical species capture alkene partners, allowing switchable intermolecular alkene difunctionalization and alkenylation in a highly stereoselective manner. In addition to acting as proton donors to facilitate H2 evolution at the cathode, the unique properties of alcohol additives play an important role in determining the distinct outcomes for alkene functionalization under electrocatalytic conditions.
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19
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Shimizu D, Kurose A, Nishikata T. Remote Nucleophilic Substitution at a C(sp 3)–H Bond of α-Bromocarboxamides via 1,4-Hydrogen Atom Transfer To Access N-Acyl- N, O-acetal Compounds. Org Lett 2022; 24:7873-7877. [DOI: 10.1021/acs.orglett.2c02716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daisuke Shimizu
- Graduate School of Science and Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan
| | - Ayako Kurose
- Graduate School of Science and Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan
| | - Takashi Nishikata
- Graduate School of Science and Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan
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20
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Zhang H, Liang S, Wei D, Xu K, Zeng C. Electrocatalytic Generation of Acyl Radicals and Their Applications. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Haonan Zhang
- Faculty of Environmental and Life Beijing University of Technology 100 Pingleyuan Rd. 100124 Beijing China
| | - Sen Liang
- Beijing Key Laboratory of Flavor Chemistry Beijing Technology and Business University 100048 Beijing China
| | - Dengchao Wei
- Faculty of Environmental and Life Beijing University of Technology 100 Pingleyuan Rd. 100124 Beijing China
| | - Kun Xu
- Faculty of Environmental and Life Beijing University of Technology 100 Pingleyuan Rd. 100124 Beijing China
| | - Chengchu Zeng
- Faculty of Environmental and Life Beijing University of Technology 100 Pingleyuan Rd. 100124 Beijing China
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21
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Goes SL, Nutting JE, Hill NJ, Stahl SS, Rafiee M. Exploring Electrosynthesis: Bulk Electrolysis and Cyclic Voltammetry Analysis of the Shono Oxidation. JOURNAL OF CHEMICAL EDUCATION 2022; 99:3242-3248. [PMID: 36277842 PMCID: PMC9580565 DOI: 10.1021/acs.jchemed.2c00221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
As electrochemistry continues to gain broader acceptance and use within the organic chemistry community, it is important that advanced undergraduate students are exposed to fundamental and practical knowledge of electrochemical applications for chemical synthesis. Herein, we describe the development of an undergraduate laboratory experience that introduces synthetic and analytical electrochemistry concepts to an advanced organic chemistry class. Experiments focus on the electrooxidative α-functionalization of carbamates, more generally known as the Shono oxidation, and include cyclic voltammetry analysis of two cyclic carbamates and a constant current bulk electrolysis reaction. The exercise offers students an authentic experience in organic electrochemistry, lays a practical and theoretical foundation for future engagement with concepts in electrochemistry and redox chemistry, and strengthens fundamental organic chemistry skills.
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Affiliation(s)
- Shannon L. Goes
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Jordan E. Nutting
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Nicholas J. Hill
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Shannon S. Stahl
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Mohammad Rafiee
- Department of Chemistry, University of Missouri–Kansas City, 5009 Rockhill Rd., Kansas City, MO 1064110, United States
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22
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Li X, Cheng Z, Liu J, Zhang Z, Song S, Jiao N. Selective desaturation of amides: a direct approach to enamides. Chem Sci 2022; 13:9056-9061. [PMID: 36091215 PMCID: PMC9365091 DOI: 10.1039/d2sc02210a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/30/2022] [Indexed: 12/18/2022] Open
Abstract
C(sp3)-H bond desaturation has been an attractive strategy in organic synthesis. Enamides are important structural fragments in pharmaceuticals and versatile synthons in organic synthesis. However, the dehydrogenation of amides usually occurs on the acyl side benefitting from enolate chemistry like the desaturation of ketones and esters. Herein, we demonstrate an Fe-assisted regioselective oxidative desaturation of amides, which provides an efficient approach to enamides and β-halogenated enamides.
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Affiliation(s)
- Xinwei Li
- State Key Laboratory of Natural and Biomimetic Drugs, Chemical Biology Center, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Zengrui Cheng
- State Key Laboratory of Natural and Biomimetic Drugs, Chemical Biology Center, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Jianzhong Liu
- State Key Laboratory of Natural and Biomimetic Drugs, Chemical Biology Center, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Ziyao Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, Chemical Biology Center, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Song Song
- State Key Laboratory of Natural and Biomimetic Drugs, Chemical Biology Center, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Ning Jiao
- State Key Laboratory of Natural and Biomimetic Drugs, Chemical Biology Center, School of Pharmaceutical Sciences, Peking University Xue Yuan Rd. 38 Beijing 100191 China
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, East China Normal University Shanghai 200062 China
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23
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Seitz AK, Kohlpaintner PJ, van Lingen T, Dyga M, Sprang F, Zirbes M, Waldvogel SR, Gooßen LJ. Concentrated Aqueous Peroxodicarbonate: Efficient Electrosyn- thesis and Use as Oxidizer in Epoxidations, S-, and N-Oxidations. Angew Chem Int Ed Engl 2022; 61:e202117563. [PMID: 35384198 PMCID: PMC9324847 DOI: 10.1002/anie.202117563] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 11/12/2022]
Abstract
Peroxodicarbonates are of substantial interest as potentially powerful and sustainable oxidizers but have so far been accessible only in low concentrations with unsatisfactory energy efficiency. Concentrated (> 0.9 mol L−1) peroxodicarbonate solutions have now been made accessible by the electrolysis of aqueous K2CO3/Na2CO3/KHCO3 solutions at high current density of 3.33 A cm−2 in an efficiently cooled circular flow reactor equipped with a boron‐doped diamond anode and a stainless‐steel cathode. Their synthetic potential as platform oxidizers was clearly demonstrated in transformations including sulfoxidation, N‐oxidation, and epoxidation.
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Affiliation(s)
- Ann-Katrin Seitz
- Evonik Chair of Organic Chemistry, Ruhr-Universität Bochum, Universitätsstr. 150, 44801, Bochum, Germany
| | - Philipp J Kohlpaintner
- Department of Chemistry, Johannes Gutenberg Universität Mainz, Duesbergweg 10-14, 55128, Mainz, Germany
| | - Tim van Lingen
- Evonik Chair of Organic Chemistry, Ruhr-Universität Bochum, Universitätsstr. 150, 44801, Bochum, Germany
| | - Marco Dyga
- Evonik Chair of Organic Chemistry, Ruhr-Universität Bochum, Universitätsstr. 150, 44801, Bochum, Germany
| | - Fiona Sprang
- Department of Chemistry, Johannes Gutenberg Universität Mainz, Duesbergweg 10-14, 55128, Mainz, Germany
| | - Michael Zirbes
- Department of Chemistry, Johannes Gutenberg Universität Mainz, Duesbergweg 10-14, 55128, Mainz, Germany
| | - Siegfried R Waldvogel
- Department of Chemistry, Johannes Gutenberg Universität Mainz, Duesbergweg 10-14, 55128, Mainz, Germany
| | - Lukas J Gooßen
- Evonik Chair of Organic Chemistry, Ruhr-Universität Bochum, Universitätsstr. 150, 44801, Bochum, Germany
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24
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Sim J, Ryou B, Choi M, Lee C, Park CM. Electrochemical C(sp 3)-H Functionalization of γ-Lactams Based on Hydrogen Atom Transfer. Org Lett 2022; 24:4264-4269. [PMID: 35675591 DOI: 10.1021/acs.orglett.2c01528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We describe the electrochemical α-amidoalkylation of γ-lactams based on transition-metal-free cross-coupling via hydrogen atom transfer. The highly selective hydrogen atom transfer process allows for a broad substrate scope including both inter- and intramolecular reactions. Also, the construction of quaternary centers was realized by a double hydrogen atom transfer protocol to afford spirocycles. Detailed mechanistic studies including experimental and computational studies are provided to support the reaction pathway.
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Affiliation(s)
| | | | | | | | - Cheol-Min Park
- Department of Chemistry, Ulsan National Institute of Science & Technology (UNIST), Ulsan 44919, Korea
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25
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Seitz A, Kohlpaintner PJ, van Lingen T, Dyga M, Sprang F, Zirbes M, Waldvogel SR, Gooßen LJ. Konzentriertes Wässriges Peroxodikarbonat: Effiziente Elektrosynthese und Anwendungen in Epoxidierungen,
S
‐, und
N
‐Oxidationen. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202117563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ann‐Katrin Seitz
- Evonik Chair of Organic Chemistry Ruhr-Universität Bochum Universitätsstr. 150 44801 Bochum Deutschland
| | - Philipp J. Kohlpaintner
- Department Chemie Johannes Gutenberg-Universität Mainz Duesbergweg 10–14 55128 Mainz Deutschland
| | - Tim van Lingen
- Evonik Chair of Organic Chemistry Ruhr-Universität Bochum Universitätsstr. 150 44801 Bochum Deutschland
| | - Marco Dyga
- Evonik Chair of Organic Chemistry Ruhr-Universität Bochum Universitätsstr. 150 44801 Bochum Deutschland
| | - Fiona Sprang
- Department Chemie Johannes Gutenberg-Universität Mainz Duesbergweg 10–14 55128 Mainz Deutschland
| | - Michael Zirbes
- Department Chemie Johannes Gutenberg-Universität Mainz Duesbergweg 10–14 55128 Mainz Deutschland
| | - Siegfried R. Waldvogel
- Department Chemie Johannes Gutenberg-Universität Mainz Duesbergweg 10–14 55128 Mainz Deutschland
| | - Lukas J. Gooßen
- Evonik Chair of Organic Chemistry Ruhr-Universität Bochum Universitätsstr. 150 44801 Bochum Deutschland
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26
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The quest for magic: recent advances in C(sp 3)–H methylation. PURE APPL CHEM 2022. [DOI: 10.1515/pac-2021-1203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Frequently referred to as the “magic methyl” effect, the introduction of a methyl group into a biologically active molecule has the potential to drastically alter its physical and biological properties and significantly increase potency. This effect is most pronounced when the methyl group is added at the α-position of an aliphatic heterocycle or ortho to a large rotatable group on an aromatic ring. Although seminal developments in C–H activation strategies offered solutions to the latter, until recent years there had been no selective and functional-group-tolerant method for C(sp3)–H methylation at late stages of synthesis. For many years, the lack of a generally applicable methylation strategy necessitated arduous de novo synthesis approaches to access methylated drug candidates, and discouraged further investigation and understandings of the magic methyl effect. This review will provide a summary of the most recent advances that enabled non-directed late-stage C(sp3)–H methylation, including through hydride transfer, chemical or anodic oxidation, and photocatalytic hydrogen atom transfer.
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27
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Feng T, Wang S, Qiu Y. Electrochemical C–H Functionalization of Cyclic Amines. Synlett 2022. [DOI: 10.1055/a-1828-1217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Functionalized cyclic amines are essential structural motifs in synthetic chemistry and pharmacy chemistry, and Shono-type oxidation is a well-developed electrochemical approach for the synthesis of α-functionalized amines. In sharp contrast, electrochemically driven direct β-C(sp3)–H functionalization of amines has been far proven elusive. Herein, we outline the recent advances in this field and highlight our group’s effort to achieve electrochemical β-C(sp3)–H functionalization assisted by ferrocene as molecular electrocatalyst under mild conditions.
1 Introduction
2 Case studies of α-functionalization (Shono-type oxidation)
3 Electrochemical β-C(sp3)–H acylation
4 Conclusion
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Affiliation(s)
- Tian Feng
- College of Chemistry, Nankai University, Tianjin, China
| | - Siyi Wang
- College of Chemistry, Nankai University, Tianjin, China
| | - Youai Qiu
- College of Chemistry, Nankai University, Tianjin, China
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28
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Allouche EMD, Simonet‐Davin R, Waser J. N-Terminal Selective C-H Azidation of Proline-Containing Peptides: a Platform for Late-Stage Diversification. Chemistry 2022; 28:e202200368. [PMID: 35137991 PMCID: PMC9306896 DOI: 10.1002/chem.202200368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Indexed: 11/08/2022]
Abstract
A methodology for the C-H azidation of N-terminal proline-containing peptides was developed employing only commercially available reagents. Peptides bearing a broad range of functionalities and containing up to 6 amino acids were selectively azidated at the carbamate-protected N-terminal residue in presence of the numerous other functional groups present on the molecules. Post-functionalizations of the obtained aminal compounds were achieved: cycloaddition reactions or C-C bond formations via a sequence of imine formation/nucleophilic addition were performed, offering an easy access to diversified peptides.
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Affiliation(s)
- Emmanuelle M. D. Allouche
- Laboratory of Catalysis and Organic SynthesisEcole Polytechnique Fédérale de LausanneEPFL, SB ISIC LCSO, BCH 43061015LausanneSwitzerland
| | - Raphaël Simonet‐Davin
- Laboratory of Catalysis and Organic SynthesisEcole Polytechnique Fédérale de LausanneEPFL, SB ISIC LCSO, BCH 43061015LausanneSwitzerland
| | - Jerome Waser
- Laboratory of Catalysis and Organic SynthesisEcole Polytechnique Fédérale de LausanneEPFL, SB ISIC LCSO, BCH 43061015LausanneSwitzerland
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29
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Kurose Y, Okamoto K, Okada Y, Kitano Y, Chiba K. Direct Anodic N‐a Hydroxylation: Accessing Versatile Intermediates for Azanucleoside Derivatives. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202100756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Yuma Kurose
- Tokyo University of Agriculture and Technology: Tokyo Noko Daigaku Applied Biological Science JAPAN
| | - Kazuhiro Okamoto
- Tokyo University of Agriculture and Technology: Tokyo Noko Daigaku Applied Biological Science JAPAN
| | - Yohei Okada
- Tokyo University of Agriculture and Technology: Tokyo Noko Daigaku Applied Biological Science JAPAN
| | - Yoshikazu Kitano
- Tokyo University of Agriculture and Technology: Tokyo Noko Daigaku Applied Biological Science JAPAN
| | - Kazuhiro Chiba
- Tokyo University of Agriculture and Technology Applied Biological Science 3-5-8 Saiwai-cho, Fuchu 183-8509 Tokyo JAPAN
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30
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Malapit CA, Prater MB, Cabrera-Pardo JR, Li M, Pham TD, McFadden TP, Blank S, Minteer SD. Advances on the Merger of Electrochemistry and Transition Metal Catalysis for Organic Synthesis. Chem Rev 2022; 122:3180-3218. [PMID: 34797053 PMCID: PMC9714963 DOI: 10.1021/acs.chemrev.1c00614] [Citation(s) in RCA: 101] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Synthetic organic electrosynthesis has grown in the past few decades by achieving many valuable transformations for synthetic chemists. Although electrocatalysis has been popular for improving selectivity and efficiency in a wide variety of energy-related applications, in the last two decades, there has been much interest in electrocatalysis to develop conceptually novel transformations, selective functionalization, and sustainable reactions. This review discusses recent advances in the combination of electrochemistry and homogeneous transition-metal catalysis for organic synthesis. The enabling transformations, synthetic applications, and mechanistic studies are presented alongside advantages as well as future directions to address the challenges of metal-catalyzed electrosynthesis.
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Affiliation(s)
- Christian A Malapit
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Matthew B Prater
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Jaime R Cabrera-Pardo
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Min Li
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Tammy D Pham
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Timothy Patrick McFadden
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Skylar Blank
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Shelley D Minteer
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
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31
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Tay NES, Lehnherr D, Rovis T. Photons or Electrons? A Critical Comparison of Electrochemistry and Photoredox Catalysis for Organic Synthesis. Chem Rev 2022; 122:2487-2649. [PMID: 34751568 PMCID: PMC10021920 DOI: 10.1021/acs.chemrev.1c00384] [Citation(s) in RCA: 131] [Impact Index Per Article: 65.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox processes are at the heart of synthetic methods that rely on either electrochemistry or photoredox catalysis, but how do electrochemistry and photoredox catalysis compare? Both approaches provide access to high energy intermediates (e.g., radicals) that enable bond formations not constrained by the rules of ionic or 2 electron (e) mechanisms. Instead, they enable 1e mechanisms capable of bypassing electronic or steric limitations and protecting group requirements, thus enabling synthetic chemists to disconnect molecules in new and different ways. However, while providing access to similar intermediates, electrochemistry and photoredox catalysis differ in several physical chemistry principles. Understanding those differences can be key to designing new transformations and forging new bond disconnections. This review aims to highlight these differences and similarities between electrochemistry and photoredox catalysis by comparing their underlying physical chemistry principles and describing their impact on electrochemical and photochemical methods.
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Affiliation(s)
- Nicholas E. S. Tay
- Department of Chemistry, Columbia University, New York, New York, 10027, United States
| | - Dan Lehnherr
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York, 10027, United States
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32
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Murray PD, Cox JH, Chiappini ND, Roos CB, McLoughlin EA, Hejna BG, Nguyen ST, Ripberger HH, Ganley JM, Tsui E, Shin NY, Koronkiewicz B, Qiu G, Knowles RR. Photochemical and Electrochemical Applications of Proton-Coupled Electron Transfer in Organic Synthesis. Chem Rev 2022; 122:2017-2291. [PMID: 34813277 PMCID: PMC8796287 DOI: 10.1021/acs.chemrev.1c00374] [Citation(s) in RCA: 166] [Impact Index Per Article: 83.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Indexed: 12/16/2022]
Abstract
We present here a review of the photochemical and electrochemical applications of multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms in which both an electron and a proton are exchanged together, often in a concerted elementary step. As such, MS-PCET can function as a non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from a wide variety of common organic functional groups. We present an introduction to MS-PCET and a practitioner's guide to reaction design, with an emphasis on the unique energetic and selectivity features that are characteristic of this reaction class. We then present chapters on oxidative N-H, O-H, S-H, and C-H bond homolysis methods, for the generation of the corresponding neutral radical species. Then, chapters for reductive PCET activations involving carbonyl, imine, other X═Y π-systems, and heteroarenes, where neutral ketyl, α-amino, and heteroarene-derived radicals can be generated. Finally, we present chapters on the applications of MS-PCET in asymmetric catalysis and in materials and device applications. Within each chapter, we subdivide by the functional group undergoing homolysis, and thereafter by the type of transformation being promoted. Methods published prior to the end of December 2020 are presented.
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Affiliation(s)
- Philip
R. D. Murray
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - James H. Cox
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Nicholas D. Chiappini
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Casey B. Roos
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | | | - Benjamin G. Hejna
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Suong T. Nguyen
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Hunter H. Ripberger
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Jacob M. Ganley
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Elaine Tsui
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Nick Y. Shin
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Brian Koronkiewicz
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Guanqi Qiu
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Robert R. Knowles
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
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33
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Novaes LFT, Ho JSK, Mao K, Liu K, Tanwar M, Neurock M, Villemure E, Terrett JA, Lin S. Exploring Electrochemical C(sp 3)-H Oxidation for the Late-Stage Methylation of Complex Molecules. J Am Chem Soc 2022; 144:1187-1197. [PMID: 35015533 DOI: 10.1021/jacs.1c09412] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The "magic methyl" effect, a dramatic boost in the potency of biologically active compounds from the incorporation of a single methyl group, provides a simple yet powerful strategy employed by medicinal chemists in the drug discovery process. Despite significant advances, methodologies that enable the selective C(sp3)-H methylation of structurally complex medicinal agents remain very limited. In this work, we disclose a modular, efficient, and selective strategy for the α-methylation of protected amines (i.e., amides, carbamates, and sulfonamides) by means of electrochemical oxidation. Mechanistic analysis guided our development of an improved electrochemical protocol on the basis of the classic Shono oxidation reaction, which features broad reaction scope, high functional group compatibility, and operational simplicity. Importantly, this reaction system is amenable to the late-stage functionalization of complex targets containing basic nitrogen groups that are prevalent in medicinally active agents. When combined with organozinc-mediated C-C bond formation, our protocol enabled the direct methylation of a myriad of amine derivatives including those that have previously been explored for the "magic methyl" effect. This synthesis strategy thus circumvents multistep de novo synthesis that is currently necessary to access such compounds and has the potential to accelerate drug discovery efforts.
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Affiliation(s)
- Luiz F T Novaes
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Justin S K Ho
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Kaining Mao
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Kaida Liu
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Mayank Tanwar
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Matthew Neurock
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Elisia Villemure
- Department of Discovery Chemistry, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Jack A Terrett
- Department of Discovery Chemistry, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Song Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
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34
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Abstract
We developed an electrochemical carboamidation sequence that affords either cyclic β-amidoamine products via direct functionalization or linear hydroxybisamide products via a ring opening pathway. The reaction pathway was dependent on the nature of the N-acyl activating group, with carbamate groups favoring direct isocyanide addition to the N-acyliminium ion intermediate and the benzoyl activating group favoring the ring opening-functionalization pathway. Both protocols are one-pot reaction sequences, have general applicability, and lead to peptide-like products of greatly increased molecular complexity.
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Affiliation(s)
- Feijun Wang
- Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, 125 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
| | - Kevin J Frankowski
- Center for Integrative Chemical Biology and Drug Discovery, UNC Eshelman School of Pharmacy, 125 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
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35
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Zou C, Wu H, He J, Hu Y, Deng W, Li X, Hu J, Li Y, Huang Y. Anodic C(sp 3)-H Acyloxylation of Indolin-3-ones Enabled by Oxidant-Free Cross-Dehydrogenative C(sp 3)-O Coupling. J Org Chem 2022; 87:1335-1347. [PMID: 34985264 DOI: 10.1021/acs.joc.1c02644] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An efficient anodic C(sp3)-H acyloxylation protocol has been established via intermolecular cross-dehydrogenative C(sp3)-O coupling. The protocol provides various C2-acyloxy indolin-3-ones without the addition of metal catalysts and external oxidants because indolin-3-ones can be directly oxidized at the anode. The effective application of several medical drugs and the realization of the gram-scale experiment have proven the practicality of this protocol.
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Affiliation(s)
- Canlin Zou
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Hongting Wu
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Jiangtao He
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Yunfei Hu
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Weijie Deng
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Xinling Li
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Jinhui Hu
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Yibiao Li
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
| | - Yubing Huang
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529090, P. R. China
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36
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Mackay AS, Payne RJ, Malins LR. Electrochemistry for the Chemoselective Modification of Peptides and Proteins. J Am Chem Soc 2022; 144:23-41. [PMID: 34968405 DOI: 10.1021/jacs.1c11185] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Although electrochemical strategies for small-molecule synthesis are flourishing, this technology has yet to be fully exploited for the mild and chemoselective modification of peptides and proteins. With the growing number of diverse peptide natural products being identified and the emergence of modified proteins as therapeutic and diagnostic agents, methods for electrochemical modification stand as alluring prospects for harnessing the reactivity of polypeptides to build molecular complexity. As a mild and inherently tunable reaction platform, electrochemistry is arguably well-suited to overcome the chemo- and regioselectivity issues which limit existing bioconjugation strategies. This Perspective will showcase recently developed electrochemical approaches to peptide and protein modification. The article also highlights the wealth of untapped opportunities for the production of homogeneously modified biomolecules, with an eye toward realizing the enormous potential of electrochemistry for chemoselective bioconjugation chemistry.
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Affiliation(s)
- Angus S Mackay
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Richard J Payne
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Lara R Malins
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, Australian National University, Canberra, ACT 2601, Australia
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37
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Lu R, Guo C. 2,2,6,6-Tetramethylpiperidinooxy (TEMPO)-Enabled Electrochemical Enantioselective Oxidative Coupling of Secondary Acyclic Amines with Ketones. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202200004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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38
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Kumar R, Banerjee P. Electrochemical Generation of a Nonstabilized Azomethine Ylide: Access to Substituted N-Heterocycles. J Org Chem 2021; 86:16104-16113. [PMID: 34734738 DOI: 10.1021/acs.joc.1c02069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Azomethine ylides are fascinating 1,3-dipoles for [3 + 2] cycloaddition reactions toward the construction of N-heterocycles. Herein, an efficient and environmentally benign electrochemical approach for the generation of a nonstabilized azomethine ylide has been established under metal-free and external oxidant-free conditions. The resulting 1,3-dipole undergoes a [3 + 2] cycloaddition reaction with olefins. This electrosynthetic methodology indulges a straightforward and facile approach for the construction of substituted pyrrolidines.
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Affiliation(s)
- Rakesh Kumar
- Department of Chemistry, Indian Institute of Technology, Ropar, Rupnagar, Punjab 140001, India
| | - Prabal Banerjee
- Department of Chemistry, Indian Institute of Technology, Ropar, Rupnagar, Punjab 140001, India
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39
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Deprez NR, Clausen DJ, Yan JX, Peng F, Zhang S, Kong J, Bai Y. Selective Electrochemical Oxidation of Functionalized Pyrrolidines. Org Lett 2021; 23:8834-8837. [PMID: 34730984 DOI: 10.1021/acs.orglett.1c03338] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A method for the selective electrochemical aminoxyl-mediated Shono-type oxidation of pyrrolidines to pyrrolidinones is described. These transformations show the high selectivity and functional group compatibility. This chemistry also demonstrates the use of an operationally simple ElectraSyn 2.0 and cost-effective stainless-steel electrode for the electrochemical oxidation of functionalized pyrrolidines.
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Affiliation(s)
- Nicholas R Deprez
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Dane J Clausen
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Jia-Xuan Yan
- Analytical Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Feng Peng
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Shaoguang Zhang
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Jongrock Kong
- Process Research and Development, Merck & Co., Inc., Rahway, New Jersey 07065, United States
| | - Yanguang Bai
- WuXi AppTec (Tianjin) Co. Ltd., Tianjin 300457, China
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40
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Nutting JE, Gerken JB, Stamoulis AG, Bruns DL, Stahl SS. "How Should I Think about Voltage? What Is Overpotential?": Establishing an Organic Chemistry Intuition for Electrochemistry. J Org Chem 2021; 86:15875-15885. [PMID: 34609137 DOI: 10.1021/acs.joc.1c01520] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Redox reactions are ubiquitous in organic synthesis and intrinsic to organic electrosynthesis. The language and concepts used to describe reactions in these domains are sufficiently different to create barriers that hinder broader adoption and understanding of electrochemical methods. To bridge these gaps, this Synopsis compares chemical and electrochemical redox reactions, including concepts of free energy, voltage, kinetic barriers, and overpotential. This discussion is intended to increase the accessibility of electrochemistry for organic chemists lacking formal training in this area.
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Affiliation(s)
- Jordan E Nutting
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - James B Gerken
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - Alexios G Stamoulis
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - David L Bruns
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - Shannon S Stahl
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
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41
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Abstract
Abstract
N-Acyl-N,O-acetals are key components in a variety of bioactive natural products. Furthermore, they are synthetic equivalents of unstable N-acylimines and building blocks in organic synthesis. Tremendous efforts have been made in the synthesis of such acetals, these methods can be broadly classified into two categories: electrochemical oxidation and chemical methods. Herein, we will summarize progress in the preparation of these subunits, which may aid the development of new synthetic methods for N-acyl-N,O-acetals.1 Introduction2 Synthetic Methods for Preparing N-Acyl-N,O-acetals2.1 Electrochemical Oxidation2.2 Chemical Methods2.3 Other Methods3 Summary and Outlook
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Affiliation(s)
- Xiao-Yan Ma
- School of Chemical Engineering, Sichuan University of Science & Engineering
| | - Fu-Qiang Shao
- Department of Nuclear Medicine, Zigong First People's Hospital & Zigong Academy of Medical Sciences
| | - Xinjun Hu
- School of Chemical Engineering, Sichuan University of Science & Engineering
- Graphene Institute of Lanzhou University Fangda Carbon, Key Laboratory of Special Function Materials and Structure Design of Ministry of Education, Lanzhou University
| | - Xingyong Liu
- School of Chemical Engineering, Sichuan University of Science & Engineering
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42
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Chowdhury S, Pandey S. A Catalyst/Oxidant/Base Free Benzylic Csp
3
−H Alkoxylation of toluidines via Electro‐oxidative Csp
3
−O‐Coupling with Alcohols. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Sushobhan Chowdhury
- Medicinal and Process Chemistry Division CSIR-Central Drug Research Institute Lucknow 226031 India
| | - Shubham Pandey
- Medicinal and Process Chemistry Division CSIR-Central Drug Research Institute Lucknow 226031 India
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43
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Wang ZH, Gao PS, Wang X, Gao JQ, Xu XT, He Z, Ma C, Mei TS. TEMPO-Enabled Electrochemical Enantioselective Oxidative Coupling of Secondary Acyclic Amines with Ketones. J Am Chem Soc 2021; 143:15599-15605. [PMID: 34533943 DOI: 10.1021/jacs.1c08671] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
An electrochemical asymmetric coupling of secondary acyclic amines with ketones via a Shono-type oxidation has been described, affording the corresponding amino acid derivatives with good to excellent diastereoselectivity and enantioselectivity. The addition of an N-oxyl radical as a redox mediator could selectively oxidize the substrate rather than the product, although their oxidation potential difference is subtle (about 13 mV). This electrochemical transformation proceeds in the absence of stoichiometric additives, including metals, oxidants, and electrolytes, which gives it good functional group compatibility. Mechanistic studies suggest that proton-mediated racemization of the product is prevented by the reduction of protons at the cathode.
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Affiliation(s)
- Zhen-Hua Wang
- Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China
| | - Pei-Sen Gao
- Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China
| | - Xiu Wang
- Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China
| | - Jun-Qing Gao
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, People's Republic of China
| | - Xue-Tao Xu
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, People's Republic of China
| | - Zeng He
- Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China
| | - Cong Ma
- Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China
| | - Tian-Sheng Mei
- Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Science, 345 Lingling Road, Shanghai 200032, People's Republic of China
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44
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Brown RCD. The Longer Route can be Better: Electrosynthesis in Extended Path Flow Cells. CHEM REC 2021; 21:2472-2487. [PMID: 34302434 DOI: 10.1002/tcr.202100163] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/02/2021] [Indexed: 01/01/2023]
Abstract
This personal account provides an overview of work conducted in my research group, and through collaborations with other chemists and engineers, to develop flow electrolysis cells and apply these cells in organic electrosynthesis. First, a brief summary of my training and background in organic synthesis is provided, leading in to the start of flow electrosynthesis in my lab in collaboration with Derek Pletcher. Our work on the development of extended path electrolysis flow reactors is described from a synthetic organic chemist's perspective, including laboratory scale-up to give several moles of an anodic methoxylation product in one day. The importance of cell design is emphasised with regards to achieving good performance in laboratory electrosynthesis with productivities from hundreds of mg h-1 to many g h-1 , at high conversion in a selective fashion. A simple design of recycle flow cell that can be readily constructed in a small University workshop is also discussed, including simple modifications to improve cell performance. Some examples of flow electrosyntheses are provided, including Shono-type oxidation, anodic cleavage of protecting groups, Hofer-Moest reaction of cubane carboxylic acids, oxidative esterification and amidation of aldehydes, and reduction of aryl halides.
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Affiliation(s)
- Richard C D Brown
- School of Chemistry, The University of Southampton, Highfield, Southampton, SO17 1BJ, UK
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45
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Najmi AA, Bhat MF, Bischoff R, Poelarends GJ, Permentier HP. TEMPO‐Mediated Electrochemical N‐demethylation of Opiate Alkaloids. ChemElectroChem 2021. [DOI: 10.1002/celc.202100784] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ali Alipour Najmi
- Department of Analytical Biochemistry Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - M. Faizan Bhat
- Department of Chemical and Pharmaceutical Biology Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - Rainer Bischoff
- Department of Analytical Biochemistry Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - Gerrit J. Poelarends
- Department of Chemical and Pharmaceutical Biology Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
| | - Hjalmar P. Permentier
- Department of Analytical Biochemistry Groningen Research Institute of Pharmacy University of Groningen A. Deusinglaan 1 9713 AV Groningen The Netherlands
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46
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Adamek J, Zieleźny P, Erfurt K. Synthesis of N-Protected 1-Aminoalkylphosphonium Salts from Amides, Carbamates, Lactams, or Imides. J Org Chem 2021; 86:5852-5862. [PMID: 33829782 PMCID: PMC8154577 DOI: 10.1021/acs.joc.1c00285] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
This report describes
the development and optimization of the one-pot
method for the synthesis of N-protected 1-aminoalkylphosphonium
salts based on the three-component coupling of aldehydes and either
amides, carbamates, lactams, imides, or urea in the presence of triarylphosphonium
salts. The proposed strategy is very efficient and easy to carry out
even on a larger scale (20 g) in any typical laboratory. Most reactions
occur at temperatures between 50 and 100 °C in a short time (1–2
h) without requiring any catalyst, and simple workup procedures afford
good to excellent yields. The exceptions are condensations with imides,
which require much higher temperatures (150–170 °C) and
longer reaction times (even 30 h). The possibility of carrying out
the synthesis under solvent-free conditions (neat reactions) is also
demonstrated. It is especially important for less reactive substrates
(imides), and reactions required high temperature (or generally harsher
conditions). Finally, we prove the developed one-pot methodology can
be successfully applied for the synthesis of structurally diverse N-protected 1-aminoalkylphosphonium salts. Mechanistic studies
showed the intermediate products of described couplings are 1-hydroxyalkylphosphonium
salts, not N-hydroxyalkylamides, -imides, etc., as
initially expected.
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Affiliation(s)
- Jakub Adamek
- Department of Organic Chemistry, Bioorganic Chemistry and Biotechnology, Silesian University of Technology, B. Krzywoustego 4, 44-100 Gliwice, Poland.,Biotechnology Center of Silesian University of Technology, B. Krzywoustego 8, 44-100 Gliwice, Poland
| | - Paulina Zieleźny
- Department of Organic Chemistry, Bioorganic Chemistry and Biotechnology, Silesian University of Technology, B. Krzywoustego 4, 44-100 Gliwice, Poland
| | - Karol Erfurt
- Department of Chemical Organic Technology and Petrochemistry, Silesian University of Technology, B. Krzywoustego 4, 44-100 Gliwice, Poland
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47
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Gunawan S, Bedard N, Foley C, Hulme C. Oxidations of pyrrolidines and piperidines to afford CH-functionalized isopropyl-1-carboxylate congeners. Tetrahedron Lett 2021; 69:152978. [PMID: 34737462 PMCID: PMC8562708 DOI: 10.1016/j.tetlet.2021.152978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
This article describes the action of iodine(III) reagents [diacetoxyiodobenzene, PhI(OAc)2, and iodosobenzene, (PhIO)n] in conjunction with TMSBr which act as functional bromine equivalents in unique oxidations of saturated, carbamate protected N-heterocycles. Interestingly, during this work, treatment of the same carbamates with molecular bromine alone afforded similar products, which were sequestered by the solvent methanol.
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Affiliation(s)
- Steven Gunawan
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721, United States
| | - Nathan Bedard
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721, United States
| | - Christopher Foley
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721, United States
| | - Christopher Hulme
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ 85721, United States,Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ 85737, United States,Corresponding author. Tel.: +1-520-626-5322;
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48
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Yamamoto K, Kuriyama M, Onomura O. Shono-Type Oxidation for Functionalization of N-Heterocycles. CHEM REC 2021; 21:2239-2253. [PMID: 33656281 DOI: 10.1002/tcr.202100031] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/24/2021] [Accepted: 02/24/2021] [Indexed: 01/05/2023]
Abstract
The development of facile synthetic methods for stereodefined aliphatic cyclic amines is an important research field in synthetic organic chemistry since such scaffolds constitute a variety of natural products and biologically active compounds. N-Acyl cyclic N,O-acetals which prepared by electrochemical oxidation of the corresponding cyclic amines have proven to be useful and versatile precursors for the synthesis of such skeletons. In this Personal Account, we introduce our efforts toward the development of synthetic strategies for the diastereo- and/or enantioselective synthesis of cyclic amines by using electrochemically prepared cyclic N,O-acetals. In addition, the investigation of the "memory of chirality" in the electrooxidative methoxylation of N-acyl amino acid derivatives, the strategy for the synthesis of chiral azabicyclic compounds by utilizing electrochemical oxidation, and halogen cation-mediated synthesis of nitrogen-containing heterocycles are also described.
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Affiliation(s)
- Kosuke Yamamoto
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
| | - Masami Kuriyama
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
| | - Osamu Onomura
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
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49
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Zou Z, Zhang W, Wang Y, Pan Y. Recent advances in electrochemically driven radical fluorination and fluoroalkylation. Org Chem Front 2021. [DOI: 10.1039/d1qo00054c] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Electrochemical fluorination (ECF) refers to the introduction of fluorine-containing moieties into organic molecules under electrochemical conditions.
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Affiliation(s)
- Zhenlei Zou
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Weigang Zhang
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Yi Wang
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Yi Pan
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
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50
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Basnet P, Sebold MB, Hendrick CE, Kozlowski MC. Copper Catalyzed Oxidative Arylation of Tertiary Carbon Centers. Org Lett 2020; 22:9524-9528. [PMID: 33263410 DOI: 10.1021/acs.orglett.0c03581] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We describe herein a Cu(OTf)2 catalyzed oxidative arylation of a tertiary carbon-containing substrate including aryl malononitriles, 3-aryl benzofuran-2-ones, and 3-aryl oxindoles. In some cases, the nitrile groups of the aryl malononitriles undergo further reactions leading to lactones or imines. These reaction conditions are applicable for a range of arenes, including phenols, anilines, anisoles, and heteroarenes. Mechanistic studies support the formation of a cationic intermediate via a two-electron oxidation.
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Affiliation(s)
- Prakash Basnet
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
| | - Melissa B Sebold
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
| | - Charles E Hendrick
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
| | - Marisa C Kozlowski
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
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