1
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Walter A, Storch G. Synthetic C6-Functionalized Aminoflavin Catalysts Enable Aerobic Bromination of Oxidation-Prone Substrates. Angew Chem Int Ed Engl 2020; 59:22505-22509. [PMID: 32790228 PMCID: PMC7756793 DOI: 10.1002/anie.202009657] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/08/2020] [Indexed: 12/19/2022]
Abstract
Flavoenzymes catalyze oxidations via hydroperoxide intermediates that result from activation of molecular O2. These reactions—such as hydroxylation and halogenation—depend on the additional catalytic activity of functional groups in the peptide environment of the flavin cofactor. We report synthetic flavin catalysts that contain C6 amino modifications at the isoalloxazine core and are consequently capable of mediating halogenations outside the peptide surrounding. The catalysts are competent in the selective, biomimetic bromination of oxidation‐prone phenols, flavones, and flavanones using a halide salt in combination with 2,6‐lutidinium oxalate as a flavin reductant under visible‐light irradiation. Our studies show the beneficial effect of stacked bisflavins as well as the catalytic activity of the flavin modifications. The designed flavin catalysts outperform isolated natural (−)‐riboflavin and contribute to the continuing search for tailored flavins in oxidation reactions.
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Affiliation(s)
- Alexandra Walter
- Department ChemieTechnische Universität MünchenLichtenbergstr. 485747GarchingGermany
| | - Golo Storch
- Department ChemieTechnische Universität MünchenLichtenbergstr. 485747GarchingGermany
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2
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Walter A, Storch G. Synthetische, C6‐funktionalisierte Aminoflavinkatalysatoren ermöglichen die aerobe Bromierung oxidationsanfälliger Substrate. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Alexandra Walter
- Department Chemie Technische Universität München Lichtenbergstr. 4 85747 Garching Deutschland
| | - Golo Storch
- Department Chemie Technische Universität München Lichtenbergstr. 4 85747 Garching Deutschland
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3
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Skubi KL, Swords WB, Hofstetter H, Yoon TP. LED-NMR Monitoring of an Enantioselective Catalytic [2+2] Photocycloaddition. CHEMPHOTOCHEM 2020; 4:685-690. [PMID: 34532566 PMCID: PMC8443221 DOI: 10.1002/cptc.202000094] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Indexed: 01/08/2023]
Abstract
We report that an NMR spectrometer equipped with a high-power LED light source can be used to study a fast enantioselective photocatalytic [2+2] cycloaddition. While traditional ex situ applications of NMR provide considerable information on reaction mechanisms, they are often ineffective for observing fast reactions. Recently, motivated by renewed interest in organic photochemistry, several approaches have been reported for in situ monitoring of photochemical reactions. These previously disclosed methods, however, have rarely been applied to rapid (<5 min) photochemical reactions. Furthermore, these approaches have not previously been used to interrogate the mechanisms of photocatalytic energy-transfer reactions. In the present work, we describe our experimental setup and demonstrate its utility by determining a phenomenological rate law for a model photocatalytic energy-transfer cycloaddition reaction.
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Affiliation(s)
- Kazimer L Skubi
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
- Department of Chemistry, Skidmore College, 815 North Broadway, Saratoga Springs, NY (USA)
| | - Wesley B Swords
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
| | - Heike Hofstetter
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
| | - Tehshik P Yoon
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
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4
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Barthelemy AL, Bourdreux F, Dagousset G, Magnier E. Photoredox-Catalyzed Selective Synthesis of Allylic Perfluoroalkanes from Alkenes. Chemistry 2020; 26:10213-10216. [PMID: 32343860 DOI: 10.1002/chem.202002046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Indexed: 12/22/2022]
Abstract
We report herein a novel photoredox-catalyzed synthesis of allylic trifluoromethanes. The use of sulfilimino iminium as a source of trifluoromethyl radicals proves crucial to achieving high selectivity. Importantly, both styrene derivatives and unactivated alkenes are for the first time suitable partners for this process. The mild reaction conditions are compatible with a variety of functional groups. Remarkably, this method is readily broadened to other perfluoroalkyl groups (RF =CFCl2 , CF2 Br, C4 F9 ). An extensive mechanistic study is also provided.
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Affiliation(s)
- Anne-Laure Barthelemy
- Institut Lavoisier de Versailles, Université Paris-Saclay, UVSQ, CNRS, UMR 8180, 78000, Versailles, France
| | - F Bourdreux
- Institut Lavoisier de Versailles, Université Paris-Saclay, UVSQ, CNRS, UMR 8180, 78000, Versailles, France
| | - Guillaume Dagousset
- Institut Lavoisier de Versailles, Université Paris-Saclay, UVSQ, CNRS, UMR 8180, 78000, Versailles, France
| | - Emmanuel Magnier
- Institut Lavoisier de Versailles, Université Paris-Saclay, UVSQ, CNRS, UMR 8180, 78000, Versailles, France
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5
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Zhang W, Carpenter KL, Lin S. Electrochemistry Broadens the Scope of Flavin Photocatalysis: Photoelectrocatalytic Oxidation of Unactivated Alcohols. Angew Chem Int Ed Engl 2020; 59:409-417. [PMID: 31617271 PMCID: PMC6923568 DOI: 10.1002/anie.201910300] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/20/2019] [Indexed: 11/10/2022]
Abstract
Riboflavin-derived photocatalysts have been extensively studied in the context of alcohol oxidation. However, to date, the scope of this catalytic methodology has been limited to benzyl alcohols. In this work, mechanistic understanding of flavin-catalyzed oxidation reactions, in either the absence or presence of thiourea as a cocatalyst, was obtained. The mechanistic insights enabled development of an electrochemically driven photochemical oxidation of primary and secondary aliphatic alcohols using a pair of flavin and dialkylthiourea catalysts. Electrochemistry makes it possible to avoid using O2 and an oxidant and generating H2 O2 as a byproduct, both of which oxidatively degrade thiourea under the reaction conditions. This modification unlocks a new mechanistic pathway in which the oxidation of unactivated alcohols is achieved by thiyl radical mediated hydrogen-atom abstraction.
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Affiliation(s)
- Wen Zhang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Keith L Carpenter
- 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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6
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Tolba AH, Vávra F, Chudoba J, Cibulka R. Tuning Flavin-Based Photocatalytic Systems for Application in the Mild Chemoselective Aerobic Oxidation of Benzylic Substrates. European J Org Chem 2019. [DOI: 10.1002/ejoc.201901628] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Amal Hassan Tolba
- Department of Organic Chemistry; University of Chemistry and Technology, Prague; Technická 5 166 28 Prague Czech Republic
| | - František Vávra
- Department of Organic Chemistry; University of Chemistry and Technology, Prague; Technická 5 166 28 Prague Czech Republic
| | - Josef Chudoba
- Central Laboratories; University of Chemistry and Technology Prague; Technická 5 166 28 Prague Czech Republic
| | - Radek Cibulka
- Department of Organic Chemistry; University of Chemistry and Technology, Prague; Technická 5 166 28 Prague Czech Republic
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7
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Zhang W, Carpenter KL, Lin S. Electrochemistry Broadens the Scope of Flavin Photocatalysis: Photoelectrocatalytic Oxidation of Unactivated Alcohols. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201910300] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Wen Zhang
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - Keith L. Carpenter
- 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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8
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Zelenka J, Cibulka R, Roithová J. Flavinium Catalysed Photooxidation: Detection and Characterization of Elusive Peroxyflavinium Intermediates. Angew Chem Int Ed Engl 2019; 58:15412-15420. [PMID: 31364790 PMCID: PMC6852162 DOI: 10.1002/anie.201906293] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/08/2019] [Indexed: 12/18/2022]
Abstract
Flavin-based catalysts are photoactive in the visible range which makes them useful in biology and chemistry. Herein, we present electrospray-ionization mass-spectrometry detection of short-lived intermediates in photooxidation of toluene catalysed by flavinium ions (Fl+ ). Previous studies have shown that photoexcited flavins react with aromates by proton-coupled electron transfer (PCET) on the microsecond time scale. For Fl+ , PCET leads to FlH.+ with the H-atom bound to the N5 position. We show that the reaction continues by coupling between FlH.+ and hydroperoxy or benzylperoxy radicals at the C4a position of FlH.+ . These results demonstrate that the N5-blocking effect reported for alkylated flavins is also active after PCET in these photocatalytic reactions. Structures of all intermediates were fully characterised by isotopic labelling and by photodissociation spectroscopy. These tools provide a new way to study reaction intermediates in the sub-second time range.
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Affiliation(s)
- Jan Zelenka
- Department of Spectroscopy and CatalysisInstitute for Molecules and MaterialsRadboud University NijmegenHeyendaalseweg 1356525AJNijmegenThe Netherlands
| | - Radek Cibulka
- Department of organic chemistryFaculty of Chemical TechnologyUniversity of Chemistry and Technology PragueTechnická 5166 28Prague 6Czech Republic
| | - Jana Roithová
- Department of Spectroscopy and CatalysisInstitute for Molecules and MaterialsRadboud University NijmegenHeyendaalseweg 1356525AJNijmegenThe Netherlands
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9
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Zelenka J, Cibulka R, Roithová J. Flavinium Catalysed Photooxidation: Detection and Characterization of Elusive Peroxyflavinium Intermediates. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201906293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jan Zelenka
- Department of Spectroscopy and Catalysis Institute for Molecules and Materials Radboud University Nijmegen Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Radek Cibulka
- Department of organic chemistry Faculty of Chemical Technology University of Chemistry and Technology Prague Technická 5 166 28 Prague 6 Czech Republic
| | - Jana Roithová
- Department of Spectroscopy and Catalysis Institute for Molecules and Materials Radboud University Nijmegen Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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10
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Ji Y, DiRocco DA, Kind J, Thiele CM, Gschwind RM, Reibarkh M. LED‐Illuminated NMR Spectroscopy: A Practical Tool for Mechanistic Studies of Photochemical Reactions. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201900109] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yining Ji
- Process Research & DevelopmentMerck & Co., Inc. Rahway New Jersey 07065 USA
| | - Daniel A. DiRocco
- Process Research & DevelopmentMerck & Co., Inc. Rahway New Jersey 07065 USA
| | - Jonas Kind
- Clemens-Schöpf-Institut für Organische Chemie und BiochemieTechnische Universität Darmstadt Alarich-Weiss-Str. 16 64287 Darmstadt Germany
| | - Christina M. Thiele
- Clemens-Schöpf-Institut für Organische Chemie und BiochemieTechnische Universität Darmstadt Alarich-Weiss-Str. 16 64287 Darmstadt Germany
| | - Ruth M. Gschwind
- Institute of Organic ChemistryUniversity of Regensburg Universitätsstrasse 31 93053 Regensburg Germany
| | - Mikhail Reibarkh
- Process Research & DevelopmentMerck & Co., Inc. Rahway New Jersey 07065 USA
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11
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Buzzetti L, Crisenza GEM, Melchiorre P. Mechanistic Studies in Photocatalysis. Angew Chem Int Ed Engl 2019; 58:3730-3747. [DOI: 10.1002/anie.201809984] [Citation(s) in RCA: 357] [Impact Index Per Article: 71.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Luca Buzzetti
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
| | - Giacomo E. M. Crisenza
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
| | - Paolo Melchiorre
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spain
- ICREA—Catalan Institution for Research and Advanced Studies Passeig Lluís Companys 23 08010 Barcelona Spain
- IIT—Istituto Italiano di TecnologiaLaboratory of Asymmetric Catalysis and Photochemistry Via Morego 30 16163 Genoa Italy
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12
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Hauptmann R, Petrosyan A, Fennel F, Argüello Cordero MA, Surkus A, Pospech J. Pyrimidopteridine
N
‐Oxide Organic Photoredox Catalysts: Characterization, Application and Non‐Covalent Interaction in Solid State. Chemistry 2019; 25:4325-4329. [DOI: 10.1002/chem.201900118] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/05/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Richy Hauptmann
- Leibniz Institute for Catalysis at theUniversity of Rostock Albert-Einstein-Strasse 29a 18059 Rostock Germany
| | - Andranik Petrosyan
- Leibniz Institute for Catalysis at theUniversity of Rostock Albert-Einstein-Strasse 29a 18059 Rostock Germany
| | - Franziska Fennel
- Institut für Physik, Dynamik molekularer SystemeUniversität Rostock Albert-Einstein-Str. 23–24 18059 Rostock Germany
| | - Miguel A. Argüello Cordero
- Leibniz Institute for Catalysis at theUniversity of Rostock Albert-Einstein-Strasse 29a 18059 Rostock Germany
- Institut für Physik, Dynamik molekularer SystemeUniversität Rostock Albert-Einstein-Str. 23–24 18059 Rostock Germany
| | - Annette‐E. Surkus
- Leibniz Institute for Catalysis at theUniversity of Rostock Albert-Einstein-Strasse 29a 18059 Rostock Germany
| | - Jola Pospech
- Leibniz Institute for Catalysis at theUniversity of Rostock Albert-Einstein-Strasse 29a 18059 Rostock Germany
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13
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Buzzetti L, Crisenza GEM, Melchiorre P. Mechanistische Studien in der Photokatalyse. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201809984] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Luca Buzzetti
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spanien
| | - Giacomo E. M. Crisenza
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spanien
| | - Paolo Melchiorre
- ICIQ—Institute of Chemical Research of Catalonia the Barcelona Institute of Science and Technology Avenida Països Catalans 16 43007 Tarragona Spanien
- ICREA—Catalan Institution for Research and Advanced Studies Passeig Lluís Companys 23 08010 Barcelona Spanien
- IIT—Istituto Italiano di TecnologiaLaboratory of Asymmetric Catalysis and Photochemistry Via Morego 30 16163 Genoa Italy
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14
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Bernarding J, Euchner F, Bruns C, Ringleb R, Müller D, Trantzschel T, Bargon J, Bommerich U, Plaumann M. Low-cost LED-based Photo-CIDNP Enables Biocompatible Hyperpolarization of 19 F for NMR and MRI at 7 T and 4.7 T. Chemphyschem 2018; 19:2453-2456. [PMID: 29944199 PMCID: PMC6220778 DOI: 10.1002/cphc.201800570] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Indexed: 11/09/2022]
Abstract
Substrates containing 19 F can serve as background-free reporter molecules for NMR and MRI. However, in vivo applications are still limited due to the lower signal-to-noise ratio (SNR) when compared with 1 H NMR. Although hyperpolarization can increase the SNR, to date, only photo-chemically induced dynamic nuclear polarization (photo-CIDNP) allows for hyperpolarization without harmful metal catalysts. Photo-CIDNP was shown to significantly enhance 19 F NMR signals of 3-fluoro-DL-tyrosine in aqueous solution using flavins as photosensitizers. However, lasers were used for photoexcitation, which is expensive and requires appropriate protection procedures in a medical or lab environment. Herein, we report 19 F MR hyperpolarization at 4.7 T and 7 T with a biocompatible system using a low-cost and easy-to-handle LED-based set-up. First hyperpolarized 19 F MR images could be acquired, because photo-CIDNP enabled repetitive hyperpolarization without adding new substrates.
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Affiliation(s)
- Johannes Bernarding
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Frederike Euchner
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Christian Bruns
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Rainer Ringleb
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Darius Müller
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Thomas Trantzschel
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Joachim Bargon
- Institute for Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Ute Bommerich
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Markus Plaumann
- Institute for Biometrics and Medical Informatics, Otto-von-Guericke University of Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
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15
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Seegerer A, Nitschke P, Gschwind RM. Combined In Situ Illumination-NMR-UV/Vis Spectroscopy: A New Mechanistic Tool in Photochemistry. Angew Chem Int Ed Engl 2018; 57:7493-7497. [PMID: 29573313 PMCID: PMC6033024 DOI: 10.1002/anie.201801250] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Indexed: 12/22/2022]
Abstract
Synthetic applications in photochemistry are booming. Despite great progress in the development of new reactions, mechanistic investigations are still challenging. Therefore, we present a fully automated in situ combination of NMR spectroscopy, UV/Vis spectroscopy, and illumination to allow simultaneous and time-resolved detection of paramagnetic and diamagnetic species. This optical fiber-based setup enables the first acquisition of combined UV/Vis and NMR spectra in photocatalysis, as demonstrated on a conPET process. Furthermore, the broad applicability of combined UVNMR spectroscopy for light-induced processes is demonstrated on a structural and quantitative analysis of a photoswitch, including rate modulation and stabilization of transient species by temperature variation. Owing to the flexibility regarding the NMR hardware, temperature, and light sources, we expect wide-ranging applications of this setup in various research fields.
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Affiliation(s)
- Andreas Seegerer
- Institute of Organic ChemistryUniversity of RegensburgUniversitätsstrasse 3193053RegensburgGermany
| | - Philipp Nitschke
- Institute of Organic ChemistryUniversity of RegensburgUniversitätsstrasse 3193053RegensburgGermany
| | - Ruth M. Gschwind
- Institute of Organic ChemistryUniversity of RegensburgUniversitätsstrasse 3193053RegensburgGermany
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16
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Seegerer A, Nitschke P, Gschwind RM. Combined In Situ Illumination-NMR-UV/Vis Spectroscopy: A New Mechanistic Tool in Photochemistry. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201801250] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Andreas Seegerer
- Institute of Organic Chemistry; University of Regensburg; Universitätsstrasse 31 93053 Regensburg Germany
| | - Philipp Nitschke
- Institute of Organic Chemistry; University of Regensburg; Universitätsstrasse 31 93053 Regensburg Germany
| | - Ruth M. Gschwind
- Institute of Organic Chemistry; University of Regensburg; Universitätsstrasse 31 93053 Regensburg Germany
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17
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Schultz DM, Lévesque F, DiRocco DA, Reibarkh M, Ji Y, Joyce LA, Dropinski JF, Sheng H, Sherry BD, Davies IW. Oxyfunctionalization of the Remote C−H Bonds of Aliphatic Amines by Decatungstate Photocatalysis. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707537] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Danielle M. Schultz
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - François Lévesque
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Daniel A. DiRocco
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Mikhail Reibarkh
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Yining Ji
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Leo A. Joyce
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - James F. Dropinski
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Huaming Sheng
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Benjamin D. Sherry
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Ian W. Davies
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
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18
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Schultz DM, Lévesque F, DiRocco DA, Reibarkh M, Ji Y, Joyce LA, Dropinski JF, Sheng H, Sherry BD, Davies IW. Oxyfunctionalization of the Remote C−H Bonds of Aliphatic Amines by Decatungstate Photocatalysis. Angew Chem Int Ed Engl 2017; 56:15274-15278. [DOI: 10.1002/anie.201707537] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/16/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Danielle M. Schultz
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - François Lévesque
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Daniel A. DiRocco
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Mikhail Reibarkh
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Yining Ji
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Leo A. Joyce
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - James F. Dropinski
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Huaming Sheng
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Benjamin D. Sherry
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
| | - Ian W. Davies
- Department of Process Research and Development, Merck Sharp & Dohme Corp.; Rahway NJ 07065 USA
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19
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Dolinski ND, Page ZA, Eisenreich F, Niu J, Hecht S, Read de Alaniz J, Hawker CJ. A Versatile Approach for In Situ Monitoring of Photoswitches and Photopolymerizations. CHEMPHOTOCHEM 2017. [DOI: 10.1002/cptc.201600045] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Neil D. Dolinski
- Materials Department, Materials Research Laboratory, UCSB University of California Santa Barbara CA 93106 USA
| | - Zachariah A. Page
- Materials Department, Materials Research Laboratory, UCSB University of California Santa Barbara CA 93106 USA
| | - Fabian Eisenreich
- Materials Department, Materials Research Laboratory, UCSB University of California Santa Barbara CA 93106 USA
- Department of Chemistry and IRIS Adlershof Humboldt-Universität zu Berlin Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Jia Niu
- Materials Department, Materials Research Laboratory, UCSB University of California Santa Barbara CA 93106 USA
| | - Stefan Hecht
- Department of Chemistry and IRIS Adlershof Humboldt-Universität zu Berlin Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Javier Read de Alaniz
- Department of Chemistry and Biochemistry, UCSB University of California Santa Barbara CA 93106 USA
| | - Craig J. Hawker
- Materials Department, Materials Research Laboratory, UCSB University of California Santa Barbara CA 93106 USA
- Department of Chemistry and Biochemistry, UCSB University of California Santa Barbara CA 93106 USA
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Metternich JB, Gilmour R. One Photocatalyst, n Activation Modes Strategy for Cascade Catalysis: Emulating Coumarin Biosynthesis with (-)-Riboflavin. J Am Chem Soc 2016; 138:1040-5. [PMID: 26714650 DOI: 10.1021/jacs.5b12081] [Citation(s) in RCA: 188] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Generating molecular complexity using a single catalyst, where the requisite activation modes are sequentially exploited as the reaction proceeds, is an attractive guiding principle in synthesis. This requires that each substrate transposition exposes a catalyst activation mode (AM) to which all preceding or future intermediates are resistant. While this concept is exemplified by MacMillan's beautiful merger of enamine and iminium ion activation, examples in other fields of contemporary catalysis remain elusive. Herein, we extend this tactic to organic photochemistry. By harnessing the two discrete photochemical activation modes of (-)-riboflavin, it is possible to sequentially induce isomerization and cyclization by energy transfer (ET) and single-electron transfer (SET) activation pathways, respectively. This catalytic approach has been utilized to emulate the coumarin biosynthesis pathway, which features a key photochemical E → Z isomerization step. Since the ensuing SET-based cyclization eliminates the need for a prefunctionalized aryl ring, this constitutes a novel disconnection of a pharmaceutically important scaffold.
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Affiliation(s)
- Jan B Metternich
- Institute for Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany
| | - Ryan Gilmour
- Institute for Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany
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Mühldorf B, Wolf R. CH Photooxygenation of Alkyl Benzenes Catalyzed by Riboflavin Tetraacetate and a Non-Heme Iron Catalyst. Angew Chem Int Ed Engl 2015; 55:427-30. [DOI: 10.1002/anie.201507170] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Indexed: 11/11/2022]
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Mühldorf B, Wolf R. Photokatalytische C-H-Oxygenierung von Alkylbenzolen mit Riboflavintetraacetat und einem Nicht-Häm-Eisenkomplex. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201507170] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Metternich JB, Gilmour R. A Bio-Inspired, Catalytic E → Z Isomerization of Activated Olefins. J Am Chem Soc 2015; 137:11254-7. [PMID: 26310905 DOI: 10.1021/jacs.5b07136] [Citation(s) in RCA: 246] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Herein, Nature's flavin-mediated activation of complex (poly)enes has been translated to a small molecule paradigm culminating in a highly (Z)-selective, catalytic isomerization of activated olefins using (-)-riboflavin (up to 99:1 Z/E). In contrast to the prominent Z → E isomerization of the natural system, it was possible to invert the directionality of the isomerization (E → Z) by simultaneously truncating the retinal scaffold, and introducing a third olefin substituent to augment A1,3-strain upon isomerization. Consequently, conjugation is reduced in the product chromophore leading to a substrate/product combination with discrete photophysical signatures. The operationally simple isomerization protocol has been applied to a variety of enone-derived substrates and showcased in the preparation of the medically relevant 4-substituted coumarin scaffold. A correlation of sensitizer triplet energy (ET) and reaction efficiency, together with the study of additive effects and mechanistic probes, is consistent with a triplet energy transfer mechanism.
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Affiliation(s)
- Jan B Metternich
- Institute for Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany
| | - Ryan Gilmour
- Institute for Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany
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