1
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Schäfer F, Lückemeier L, Glorius F. Improving reproducibility through condition-based sensitivity assessments: application, advancement and prospect. Chem Sci 2024:d4sc03017f. [PMID: 39263664 PMCID: PMC11382186 DOI: 10.1039/d4sc03017f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 08/29/2024] [Indexed: 09/13/2024] Open
Abstract
The fluctuating reproducibility of scientific reports presents a well-recognised issue, frequently stemming from insufficient standardisation, transparency and a lack of information in scientific publications. Consequently, the incorporation of newly developed synthetic methods into practical applications often occurs at a slow rate. In recent years, various efforts have been made to analyse the sensitivity of chemical methodologies and the variation in quantitative outcome observed across different laboratory environments. For today's chemists, determining the key factors that really matter for a reaction's outcome from all the different aspects of chemical methodology can be a challenging task. In response, we provide a detailed examination and customised recommendations surrounding the sensitivity screen, offering a comprehensive assessment of various strategies and exploring their diverse applications by research groups to improve the practicality of their methodologies.
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Affiliation(s)
- Felix Schäfer
- Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
| | - Lukas Lückemeier
- Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
| | - Frank Glorius
- Universität Münster, Organisch-Chemisches Institut Corrensstraße 36 48149 Münster Germany
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2
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Schrader ML, Schäfer FR, Schäfers F, Glorius F. Bridging the information gap in organic chemical reactions. Nat Chem 2024; 16:491-498. [PMID: 38548884 DOI: 10.1038/s41557-024-01470-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 02/02/2024] [Indexed: 04/07/2024]
Abstract
The varying quality of scientific reports is a well-recognized problem and often results from a lack of standardization and transparency in scientific publications. This situation ultimately leads to prominent complications such as reproducibility issues and the slow uptake of newly developed synthetic methods for pharmaceutical and agrochemical applications. In recent years, various impactful approaches have been advocated to bridge information gaps and to improve the quality of experimental protocols in synthetic organic publications. Here we provide a critical overview of these strategies and present the reader with a versatile set of tools to augment their standard procedures. We formulate eight principles to improve data management in scientific publications relating to data standardization, reproducibility and evaluation, and encourage scientists to go beyond current publication standards. We are aware that this is a substantial effort, but we are convinced that the resulting improved data situation will greatly benefit the progress of chemistry.
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Affiliation(s)
- Malte L Schrader
- Organisch-Chemisches Institut, Universität Münster, Münster, Germany
| | - Felix R Schäfer
- Organisch-Chemisches Institut, Universität Münster, Münster, Germany
| | - Felix Schäfers
- Organisch-Chemisches Institut, Universität Münster, Münster, Germany
| | - Frank Glorius
- Organisch-Chemisches Institut, Universität Münster, Münster, Germany.
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3
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Abstract
Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N-O•. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N═O+) or reduced to anions (R1R2N-O-), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C-O bonds, allowing for the thermal generation of C radicals through reversible C-O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.
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Affiliation(s)
- Dirk Leifert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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4
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Barrington H, Dickinson A, McGuire J, Yan C, Reid M. Computer Vision for Kinetic Analysis of Lab- and Process-Scale Mixing Phenomena. Org Process Res Dev 2022; 26:3073-3088. [PMID: 36437899 PMCID: PMC9680030 DOI: 10.1021/acs.oprd.2c00216] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Indexed: 11/06/2022]
Abstract
A software platform for the computer vision-enabled analysis of mixing phenomena of relevance to process scale-up is described. By bringing new and known time-resolved mixing metrics under one platform, hitherto unavailable comparisons of pixel-derived mixing metrics are exemplified across non-chemical and chemical processes. The analytical methods described are applicable using any camera and across an appreciable range of reactor scales, from development through to process scale-up. A case study in nucleophilic aromatic substitution run on a 5 L scale in a stirred tank reactor shows how camera and offline concentration analyses can be correlated. In some cases, it can be shown that camera data hold the power to predict reaction progress.
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Affiliation(s)
- Henry Barrington
- Department
of Pure & Applied Chemistry, University
of Strathclyde, Royal
College Building 204 George Street, Glasgow G1 1XW, U.K.
| | - Alan Dickinson
- Colorants
Technology Centre, FUJIFILM Imaging Colorants, Earls Road, Grangemouth FK3 8XG, U.K.
| | - Jake McGuire
- Department
of Pure & Applied Chemistry, University
of Strathclyde, Royal
College Building 204 George Street, Glasgow G1 1XW, U.K.
| | - Chunhui Yan
- Department
of Pure & Applied Chemistry, University
of Strathclyde, Royal
College Building 204 George Street, Glasgow G1 1XW, U.K.
| | - Marc Reid
- Department
of Pure & Applied Chemistry, University
of Strathclyde, Royal
College Building 204 George Street, Glasgow G1 1XW, U.K.
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5
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Hilt G, Jamshidi M, Fastie C. Applications of Alternating Current/Alternating Potential Electrolysis in Organic Synthesis. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/s-0042-1751367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
AbstractThis review summarises the rarely used method of alternating current electrolysis for the synthesis of organic products. Different waveforms have been investigated which opens the possibility for further influence the outcome of the electrolysis by variation of the frequency as well as the highest peak current. In recent years alternating current electrolysis has been applied in increasingly more complex transformations. Especially the functionalisation of (hetero)arenes, functional group manipulation, metathesis reactions, and transition-metal-catalysed cross-coupling reactions were reported in recent years and the results of these and some other investigations are summarized in this review article.1 Introduction1.1 Waveforms1.2 Objectives1.3 Early Examples of the Optimisation of Alternating Current Electrolysis2 Recent Applications of Alternating Current Electrolysis for Organic Synthesis2.1 Substitution Reaction on Arenes2.2 Nitrogen–Sulfur Bond Formation and Sulfur–Sulfur Bond Metathesis2.3 Oxidation and Reduction2.4 Cross-Coupling Reactions2.5 Frequency Optimisation3 Conclusion
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6
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Wu S, Kaur J, Karl TA, Tian X, Barham JP. Synthetic Molecular Photoelectrochemistry: New Frontiers in Synthetic Applications, Mechanistic Insights and Scalability. Angew Chem Int Ed Engl 2022; 61:e202107811. [PMID: 34478188 PMCID: PMC9303540 DOI: 10.1002/anie.202107811] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Indexed: 11/11/2022]
Abstract
Synthetic photoelectrochemistry (PEC) is receiving increasing attention as a new frontier for the generation and handling of reactive intermediates. PEC permits selective single-electron transfer (SET) reactions in a much greener way and broadens the redox window of possible transformations. Herein, the most recent contributions are reviewed, demonstrating exciting new opportunities, namely, the combination of PEC with other reactivity paradigms (hydrogen-atom transfer, radical polar crossover, energy transfer sensitization), scalability up to multigram scale, novel selectivities in SET super-oxidations/reductions and the importance of precomplexation to temporally enable excited radical ion catalysis.
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Affiliation(s)
- Shangze Wu
- Universität RegensburgFakultät für Chemie und Pharmazie93040RegensburgGermany
| | - Jaspreet Kaur
- Universität RegensburgFakultät für Chemie und Pharmazie93040RegensburgGermany
| | - Tobias A. Karl
- Universität RegensburgFakultät für Chemie und Pharmazie93040RegensburgGermany
| | - Xianhai Tian
- Universität RegensburgFakultät für Chemie und Pharmazie93040RegensburgGermany
| | - Joshua P. Barham
- Universität RegensburgFakultät für Chemie und Pharmazie93040RegensburgGermany
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7
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Holman SDL, Wills AG, Fazakerley NJ, Poole DL, Coe DM, Berlouis LA, Reid M. Electrochemical Synthesis of Isoxazolines: Method and Mechanism. Chemistry 2022; 28:e202103728. [PMID: 35076117 PMCID: PMC9303936 DOI: 10.1002/chem.202103728] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Indexed: 11/11/2022]
Abstract
An electrochemical method for the green and practical synthesis of a broad range of substituted isoxazoline cores is presented. Both aryl and more challenging alkyl aldoximes are converted to the desired isoxazoline in an electrochemically enabled regio‐ and diastereoselective reaction with electron‐deficient alkenes. Additionally, in‐situ reaction monitoring methods compatible with electrochemistry equipment have been developed in order to probe the reaction pathway. Supporting analyses from kinetic (time‐course) modelling and density functional theory support a stepwise, radical‐mediated mechanism, and discounts hypothesised involvement of closed shell [3+2] cycloaddition pathways.
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Affiliation(s)
- Samuel D. L. Holman
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde Royal College Building 204 George Street Glasgow G1 1XW UK
- GlaxoSmithKline Medicines Research Centre Gunnels Wood Road Stevenage SG1 2NY UK
| | - Alfie G. Wills
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde Royal College Building 204 George Street Glasgow G1 1XW UK
- GlaxoSmithKline Medicines Research Centre Gunnels Wood Road Stevenage SG1 2NY UK
| | - Neal J. Fazakerley
- GlaxoSmithKline Medicines Research Centre Gunnels Wood Road Stevenage SG1 2NY UK
| | - Darren L. Poole
- GlaxoSmithKline Medicines Research Centre Gunnels Wood Road Stevenage SG1 2NY UK
| | - Diane M. Coe
- GlaxoSmithKline Medicines Research Centre Gunnels Wood Road Stevenage SG1 2NY UK
| | - Leonard A. Berlouis
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde Royal College Building 204 George Street Glasgow G1 1XW UK
| | - Marc Reid
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde Royal College Building 204 George Street Glasgow G1 1XW UK
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8
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Wu S, Kaur J, Karl TA, Tian X, Barham JP. Synthetische molekulare Photoelektrochemie: neue synthetische Anwendungen, mechanistische Einblicke und Möglichkeiten zur Skalierung. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202107811] [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)
- Shangze Wu
- Universität Regensburg Fakultät für Chemie und Pharmazie 93040 Regensburg Deutschland
| | - Jaspreet Kaur
- Universität Regensburg Fakultät für Chemie und Pharmazie 93040 Regensburg Deutschland
| | - Tobias A. Karl
- Universität Regensburg Fakultät für Chemie und Pharmazie 93040 Regensburg Deutschland
| | - Xianhai Tian
- Universität Regensburg Fakultät für Chemie und Pharmazie 93040 Regensburg Deutschland
| | - Joshua P. Barham
- Universität Regensburg Fakultät für Chemie und Pharmazie 93040 Regensburg Deutschland
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9
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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: 181] [Impact Index Per Article: 60.3] [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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10
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Strehl J, Hilt G. Synthesis of Symmetrical and Unsymmetrical Thiosulfonates from Disulfides through Electrochemically Induced Disulfide Bond Metathesis and Site‐Selective Oxidation. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Julia Strehl
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26111 Oldenburg Germany
| | - Gerhard Hilt
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26111 Oldenburg Germany
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11
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Kawamata Y, Hayashi K, Carlson E, Shaji S, Waldmann D, Simmons BJ, Edwards JT, Zapf CW, Saito M, Baran PS. Chemoselective Electrosynthesis Using Rapid Alternating Polarity. J Am Chem Soc 2021; 143:16580-16588. [PMID: 34596395 PMCID: PMC8711284 DOI: 10.1021/jacs.1c06572] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Challenges in the selective manipulation of functional groups (chemoselectivity) in organic synthesis have historically been overcome either by using reagents/catalysts that tunably interact with a substrate or through modification to shield undesired sites of reactivity (protecting groups). Although electrochemistry offers precise redox control to achieve unique chemoselectivity, this approach often becomes challenging in the presence of multiple redox-active functionalities. Historically, electrosynthesis has been performed almost solely by using direct current (DC). In contrast, applying alternating current (AC) has been known to change reaction outcomes considerably on an analytical scale but has rarely been strategically exploited for use in complex preparative organic synthesis. Here we show how a square waveform employed to deliver electric current-rapid alternating polarity (rAP)-enables control over reaction outcomes in the chemoselective reduction of carbonyl compounds, one of the most widely used reaction manifolds. The reactivity observed cannot be recapitulated using DC electrolysis or chemical reagents. The synthetic value brought by this new method for controlling chemoselectivity is vividly demonstrated in the context of classical reactivity problems such as chiral auxiliary removal and cutting-edge medicinal chemistry topics such as the synthesis of PROTACs.
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Affiliation(s)
- Yu Kawamata
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Kyohei Hayashi
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Ethan Carlson
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Shobin Shaji
- IKA Works, Inc., 3550 General Atomics Court, MS G02/321, San Diego, California 92121, United States
| | - Dirk Waldmann
- IKA Works, Inc., 3550 General Atomics Court, MS G02/321, San Diego, California 92121, United States
- IKA-Werke GmbH & Co. KG Janke & Kunkel-Straße 10, Staufen 79219, Germany
| | - Bryan J Simmons
- Bristol Myers Squibb, 10300 Campus Point Drive Suite 100, San Diego, California 92121, United States
| | - Jacob T Edwards
- Bristol Myers Squibb, 10300 Campus Point Drive Suite 100, San Diego, California 92121, United States
| | - Christoph W Zapf
- Bristol Myers Squibb, 10300 Campus Point Drive Suite 100, San Diego, California 92121, United States
| | - Masato Saito
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Phil S Baran
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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12
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Marken F, Cresswell AJ, Bull SD. Recent Advances in Paired Electrosynthesis. CHEM REC 2021; 21:2585-2600. [PMID: 33834595 DOI: 10.1002/tcr.202100047] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/31/2021] [Indexed: 11/08/2022]
Abstract
Progress in electroorganic synthesis is linked to innovation of new synthetic reactions with impact on medicinal chemistry and drug discovery and to the desire to minimise waste and to provide energy-efficient chemical transformations for future industrial processes. Paired electrosynthetic processes that combine the use of both anode and cathode (convergent or divergent) with minimal (or without) intentionally added electrolyte or need for additional reagents are of growing interest. In this overview, recent progress in developing paired electrolytic reactions is surveyed. The discussion focuses on electrosynthesis technology with proven synthetic value for the preparation of small molecules. Reactor types are contrasted and the concept of translating light-energy driven photoredox reactions into paired electrolytic reactions is highlighted as a newly emerging trend.
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Affiliation(s)
- Frank Marken
- Department of Chemistry, University of Bath, Claverton Down, BA27AY, Bath, UK
| | | | - Steven D Bull
- Department of Chemistry, University of Bath, Claverton Down, BA27AY, Bath, UK
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13
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Zhu C, Ang NWJ, Meyer TH, Qiu Y, Ackermann L. Organic Electrochemistry: Molecular Syntheses with Potential. ACS CENTRAL SCIENCE 2021; 7:415-431. [PMID: 33791425 PMCID: PMC8006177 DOI: 10.1021/acscentsci.0c01532] [Citation(s) in RCA: 331] [Impact Index Per Article: 82.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Indexed: 05/05/2023]
Abstract
Efficient and selective molecular syntheses are paramount to inter alia biomolecular chemistry and material sciences as well as for practitioners in chemical, agrochemical, and pharmaceutical industries. Organic electrosynthesis has undergone a considerable renaissance and has thus in recent years emerged as an increasingly viable platform for the sustainable molecular assembly. In stark contrast to early strategies by innate reactivity, electrochemistry was recently merged with modern concepts of organic synthesis, such as transition-metal-catalyzed transformations for inter alia C-H functionalization and asymmetric catalysis. Herein, we highlight the unique potential of organic electrosynthesis for sustainable synthesis and catalysis, showcasing key aspects of exceptional selectivities, the synergism with photocatalysis, or dual electrocatalysis, and novel mechanisms in metallaelectrocatalysis until February of 2021.
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Affiliation(s)
- Cuiju Zhu
- Institut
für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Nate W. J. Ang
- Institut
für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Tjark H. Meyer
- Institut
für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
- Woehler
Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany
| | - Youai Qiu
- Institut
für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Lutz Ackermann
- Institut
für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
- Woehler
Research Institute for Sustainable Chemistry (WISCh), Georg-August-Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany
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14
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Nemez DB, Sidhu BK, Giesbrecht PK, Braun JD, Herbert DE. Electrochemical hydrogenation of α-ketoesters and benzoxazinones using carbon electrodes and a sustainable Brønsted acid. Org Chem Front 2021. [DOI: 10.1039/d0qo01311k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A convenient electrochemical methodology for the hydrogenation of benzoxazinones and aryl-substituted α-ketoester substrates is presented, using carbon electrodes and sustainable Brønsted acids.
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Affiliation(s)
- Dion B. Nemez
- Department of Chemistry
- University of Manitoba
- Winnipeg
- Canada
| | | | | | - Jason D. Braun
- Department of Chemistry
- University of Manitoba
- Winnipeg
- Canada
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15
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Schotten C, Taylor CJ, Bourne RA, Chamberlain TW, Nguyen BN, Kapur N, Willans CE. Alternating polarity for enhanced electrochemical synthesis. REACT CHEM ENG 2021. [DOI: 10.1039/d0re00399a] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Improved synthesis through the use of alternating polarity.
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Affiliation(s)
| | | | - Richard A. Bourne
- School of Chemical and Process Engineering
- University of Leeds
- Leeds LS2 9JT
- UK
| | | | - Bao N. Nguyen
- School of Chemistry
- University of Leeds
- Leeds LS2 9JT
- UK
| | - Nik Kapur
- School of Mechanical Engineering
- University of Leeds
- Leeds LS2 9JT
- UK
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16
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Heard DM, Lennox AJJ. Electrode Materials in Modern Organic Electrochemistry. Angew Chem Int Ed Engl 2020; 59:18866-18884. [PMID: 32633073 PMCID: PMC7589451 DOI: 10.1002/anie.202005745] [Citation(s) in RCA: 183] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Indexed: 11/11/2022]
Abstract
The choice of electrode material is critical for achieving optimal yields and selectivity in synthetic organic electrochemistry. The material imparts significant influence on the kinetics and thermodynamics of electron transfer, and frequently defines the success or failure of a transformation. Electrode processes are complex and so the choice of a material is often empirical and the underlying mechanisms and rationale for success are unknown. In this review, we aim to highlight recent instances of electrode choice where rationale is offered, which should aid future reaction development.
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Affiliation(s)
- David M. Heard
- University of BristolSchool of ChemistryCantocks CloseBristol, AvonBS8 1TSUK
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17
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Affiliation(s)
- David M. Heard
- University of Bristol School of Chemistry Cantocks Close Bristol, Avon BS8 1TS UK
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