1
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Bera N, Lenka BS, König B, Sarkar D. Riboflavin Photocatalyzed Dearomative Spiro-Etherification of Naphthols. J Org Chem 2023. [PMID: 37356110 DOI: 10.1021/acs.joc.2c03037] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
The dearomative spiro-etherification of naphthols is achieved using catalytic amounts of riboflavin tetracetate (RFTA) as a photosensitizer and molecular oxygen as a terminal oxidizing agent under blue light (440 nm) irradiation in the presence of acid. The presence of acid increases the photooxidation power of RFTA and facilitates the dearomatization reaction.
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Affiliation(s)
- Nabakumar Bera
- Department of Chemistry, National Institute of Technology, Rourkela, Rourkela 769008, India
| | - Bhabani Sankar Lenka
- Department of Chemistry, Indian Institute of Technology, Indore, Madhya Pradesh 453552, India
| | - Burkhard König
- Department of Chemistry and Pharmazie, University of Regensburg, 93040 Regensburg, Germany
| | - Debayan Sarkar
- Department of Chemistry, Indian Institute of Technology, Indore, Madhya Pradesh 453552, India
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2
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Rehpenn A, Walter A, Storch G. Molecular flavin catalysts for C-H functionalisation and derivatisation of dehydroamino acids. Chem Sci 2022; 13:14151-14156. [PMID: 36540823 PMCID: PMC9728571 DOI: 10.1039/d2sc04341f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 11/04/2022] [Indexed: 03/12/2024] Open
Abstract
In nature, the isoalloxazine heterocycle of flavin cofactors undergoes reversible covalent bond formation with a variety of different reaction partners. These intermediates play a crucial role inter alia as the signalling states and in selective catalysis reactions. In the organic laboratory, covalent adducts with a new carbon-carbon bond have been observed with photochemically excited flavins but have, so far, only been regarded as dead-end side products. We have identified a series of molecular flavins that form adducts resulting in a new C-C bond at the C4a-position through allylic C-H activation and dehydroamino acid oxidation. Typically, these reactions are of radical nature and a stepwise pathway is assumed. We could demonstrate that these adducts are no dead-end and that the labile C-C bond can be cleaved by adding the persistent radical TEMPO leading to flavin regeneration and alkoxyamine-functionalised substrates. Our method allows for the catalytic oxidation of dehydroamino acids (16 examples) and we show that the acylimine products serve as versatile starting points for diversification. The present results are envisioned to stimulate the design of further catalytic reactions involving intermediates at the flavin C4a-position and their reactivity towards metal complexes or other persistent organic radicals. Our method for dehydrobutyrine derivatisation is orthogonal to the currently used methods (i.e., nucleophilic attack or radical addition) and offers new perspectives for peptide natural product diversification.
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Affiliation(s)
- Andreas Rehpenn
- School of Natural Sciences and Catalysis Research Center (CRC), Technical University of Munich (TUM) Lichtenbergstr. 4 85747 Garching Germany
| | - Alexandra Walter
- School of Natural Sciences and Catalysis Research Center (CRC), Technical University of Munich (TUM) Lichtenbergstr. 4 85747 Garching Germany
| | - Golo Storch
- School of Natural Sciences and Catalysis Research Center (CRC), Technical University of Munich (TUM) Lichtenbergstr. 4 85747 Garching Germany
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3
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Deng Y, Yang T, Wang H, Yang C, Cheng L, Yin SF, Kambe N, Qiu R. Recent Progress on Photocatalytic Synthesis of Ester Derivatives and Reaction Mechanisms. Top Curr Chem (Cham) 2021; 379:42. [PMID: 34668085 DOI: 10.1007/s41061-021-00355-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 10/05/2021] [Indexed: 11/28/2022]
Abstract
Esters and their derivatives are distributed widely in natural products, pharmaceuticals, fine chemicals and other fields. Esters are important building blocks in pharmaceuticals such as clopidogrel, methylphenidate, fenofibrate, travoprost, prasugrel, oseltamivir, eszopiclone and fluticasone. Therefore, esterification reaction becomes more and more popular in the photochemical field. In this review, we highlight three types of reactions to synthesize esters using photochemical strategies. The reaction mechanisms involve mainly single electron transfer, energy transfer or other radical procedures.
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Affiliation(s)
- Yiqiang Deng
- College of Chemical Engineering, Key Laboratory of Inferior Crude Oil Upgrade Processing of Guangdong Provincial Higher Education Institutes, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China.
| | - Tianbao Yang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Hui Wang
- College of Chemical Engineering, Key Laboratory of Inferior Crude Oil Upgrade Processing of Guangdong Provincial Higher Education Institutes, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China
| | - Chong Yang
- College of Chemical Engineering, Key Laboratory of Inferior Crude Oil Upgrade Processing of Guangdong Provincial Higher Education Institutes, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China
| | - Lihua Cheng
- College of Chemical Engineering, Key Laboratory of Inferior Crude Oil Upgrade Processing of Guangdong Provincial Higher Education Institutes, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China
| | - Shuang-Feng Yin
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Nobuaki Kambe
- The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Renhua Qiu
- College of Chemical Engineering, Key Laboratory of Inferior Crude Oil Upgrade Processing of Guangdong Provincial Higher Education Institutes, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China. .,State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
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4
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Nikitas NF, Apostolopoulou MK, Skolia E, Tsoukaki A, Kokotos CG. Photochemical Activation of Aromatic Aldehydes: Synthesis of Amides, Hydroxamic Acids and Esters. Chemistry 2021; 27:7915-7922. [PMID: 33772903 DOI: 10.1002/chem.202100655] [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: 02/21/2021] [Indexed: 12/17/2022]
Abstract
A cheap, facile and metal-free photochemical protocol for the activation of aromatic aldehydes has been developed. Utilizing thioxanthen-9-one as the photocatalyst and cheap household lamps as the light source, a variety of aromatic aldehydes have been activated and subsequently converted in a one-pot reaction into amides, hydroxamic acids and esters in good to high yields. The applicability of this method was highlighted in the synthesis of Moclobemide, a drug against depression and social anxiety. Extended and detailed mechanistic studies have been conducted, in order to determine a plausible mechanism for the reaction.
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Affiliation(s)
- Nikolaos F Nikitas
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Panepistimioupolis, 15771, Athens, Greece
| | - Mary K Apostolopoulou
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Panepistimioupolis, 15771, Athens, Greece
| | - Elpida Skolia
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Panepistimioupolis, 15771, Athens, Greece
| | - Anna Tsoukaki
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Panepistimioupolis, 15771, Athens, Greece
| | - Christoforos G Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Panepistimioupolis, 15771, Athens, Greece
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5
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Srivastava V, Singh PK, Srivastava A, Singh PP. Synthetic applications of flavin photocatalysis: a review. RSC Adv 2021. [DOI: 10.1039/d1ra00925g] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Encouraging developments in the field of photocatalysis in last decades, biomolecules namely flavins have been observed to act as a catalyst in several photoredox-catalysed synthetic methodologies.
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Affiliation(s)
- Vishal Srivastava
- Department of Chemistry
- CMP Degree College
- University of Allahabad
- Prayagraj 211002
- India
| | - Pravin K. Singh
- Department of Chemistry
- CMP Degree College
- University of Allahabad
- Prayagraj 211002
- India
| | - Arjita Srivastava
- Department of Chemistry
- CMP Degree College
- University of Allahabad
- Prayagraj 211002
- India
| | - Praveen P. Singh
- Department of Chemistry
- United College of Engineering & Research
- Prayagraj 211010
- India
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6
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Cheng S, Ou C, Lin H, Jia J, Tang H, Pan Y, Huang G, Meng X. Electrochemically Mediated Esterification of Aromatic Aldehydes with Aliphatic Alcohols via Anodic Oxidation. CHINESE J ORG CHEM 2021. [DOI: 10.6023/cjoc202110019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Arakawa Y, Mihara T, Fujii H, Minagawa K, Imada Y. An uncommon use of irradiated flavins: Brønsted acid catalysis. Chem Commun (Camb) 2020; 56:5661-5664. [PMID: 32315001 DOI: 10.1039/d0cc01960g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We present that thioacetalization of aldehydes can be induced by blue light irradiation in the presence of a catalytic amount of riboflavin tetraacetate (RFTA) under aerobic conditions. Several control experiments have suggested that the reaction is more likely to be catalyzed by acidic species generated in situ upon light irradiation. We have proposed that single electron transfer from a thiol (RSH) to the excited state of RFTA can take place to give a one-electron oxidized thiol (RSH+˙) and the one-electron reduced RFTA (RFTA-˙), which can be trapped by molecular oxygen to be stabilized as Brønsted acids including the protonated RFTA-˙ (RFTAH˙). Finally, we have demonstrated that such acidic species can be prepared in advance as a solution and used as Brønsted acid catalysts for not only thioacetalization but also Mannich-type reactions.
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Affiliation(s)
- Yukihiro Arakawa
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan.
| | - Tomohiro Mihara
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan.
| | - Hiroki Fujii
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan.
| | - Keiji Minagawa
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan. and Institute of Liberal Arts and Sciences, Tokushima University, Minamijosanjima, Tokushima 770-8502, Japan
| | - Yasushi Imada
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan.
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8
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9
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Talukdar R. Ir III-Catalyzed direct syntheses of amides and esters using nitriles as acid equivalents: a photochemical pathway. NEW J CHEM 2020. [DOI: 10.1039/d0nj00002g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
An unprecedented IrIII[df(CF3)ppy]2(dtbbpy)PF6-catalyzed simple photochemical process for direct addition of amines and alcohols to the relatively less reactive nitrile triple bond is described herein.
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Affiliation(s)
- Ranadeep Talukdar
- Molecular Synthesis and Drug Discovery Laboratory
- Centre of Biomedical Research
- Sanjay Gandhi Postgraduate Institute of Medical Sciences
- Lucknow 226014
- India
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10
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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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11
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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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12
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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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13
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Tagami T, Arakawa Y, Minagawa K, Imada Y. Efficient Use of Photons in Photoredox/Enamine Dual Catalysis with a Peptide-Bridged Flavin-Amine Hybrid. Org Lett 2019; 21:6978-6982. [PMID: 31403307 DOI: 10.1021/acs.orglett.9b02567] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
An isoalloxazine (flavin) ring system and a secondary amine have been integrated through a short peptide linker with the aim of using photons as efficiently as possible in photoredox/enamine dual catalysis. We herein report a peptide-bridged flavin-amine hybrid that can catalyze α-oxyamination of aldehydes with TEMPO under weak blue light irradiation to achieve an extremely high quantum yield of reaction (Φ = 0.80).
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Affiliation(s)
- Takuma Tagami
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
| | - Yukihiro Arakawa
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
| | - Keiji Minagawa
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan.,Institute of Liberal Arts and Sciences, Tokushima University, Minamijosanjima, Tokushima 770-8502, Japan
| | - Yasushi Imada
- Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
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14
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Gaspa S, Raposo I, Pereira L, Mulas G, Ricci PC, Porcheddu A, De Luca L. Visible light-induced transformation of aldehydes to esters, carboxylic anhydrides and amides. NEW J CHEM 2019. [DOI: 10.1039/c9nj01984g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A transition metal- and organophotocatalyst free synthesis of esters, carboxylic anhydrides and amides from aldehydes induced by visible-light has been reported.
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Affiliation(s)
- Silvia Gaspa
- Dipartimento di Chimica e Farmacia
- Università degli Studi di Sassari
- 07100 Sassari
- Italy
| | - Inês Raposo
- Dipartimento di Chimica e Farmacia
- Università degli Studi di Sassari
- 07100 Sassari
- Italy
| | - Leonor Pereira
- Dipartimento di Chimica e Farmacia
- Università degli Studi di Sassari
- 07100 Sassari
- Italy
| | - Gabriele Mulas
- Dipartimento di Chimica e Farmacia
- Università degli Studi di Sassari
- 07100 Sassari
- Italy
| | - Pier Carlo Ricci
- Dipartimento di Fisica
- Università degli Studi di Cagliari
- Cittadella Universitaria
- 09042 Monserrato
- Italy
| | - Andrea Porcheddu
- Dipartimento di Scienze Chimiche e Geologiche
- Università degli Studi di Cagliari
- Cittadella Universitaria
- 09042 Monserrato
- Italy
| | - Lidia De Luca
- Dipartimento di Chimica e Farmacia
- Università degli Studi di Sassari
- 07100 Sassari
- Italy
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15
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Zelenka J, Svobodová E, Tarábek J, Hoskovcová I, Boguschová V, Bailly S, Sikorski M, Roithová J, Cibulka R. Combining Flavin Photocatalysis and Organocatalysis: Metal-Free Aerobic Oxidation of Unactivated Benzylic Substrates. Org Lett 2018; 21:114-119. [PMID: 30582822 DOI: 10.1021/acs.orglett.8b03547] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We report a system with ethylene-bridged flavinium salt 2b which catalyzes the aerobic oxidation of toluenes and benzyl alcohols with high oxidation potential ( Eox > +2.5 V vs SCE) to give the corresponding benzoic acids under visible light irradiation. This is caused by the high oxidizing power of excited 2b ( E(2b*) = +2.67 V vs SCE) involved in photooxidation and by the accompanying dark organocatalytic oxygenation provided by the in situ formed flavin hydroperoxide 2b-OOH.
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Affiliation(s)
- Jan Zelenka
- Institute for Molecules and Materials , Radboud University , Heyendaalseweg 135 , 6525 AJ Nijmegen , The Netherlands
| | | | - Ján Tarábek
- Institute of Organic Chemistry and Biochemistry , Academy of Science of the Czech Republic , Flemingovo náměstí 542/2 , 16610 Prague , Czech Republic
| | | | | | | | - Marek Sikorski
- Faculty of Chemistry ; Adam Mickiewicz University in Poznan , Umultowska 89b , 61614 Poznan , Poland
| | - Jana Roithová
- Institute for Molecules and Materials , Radboud University , Heyendaalseweg 135 , 6525 AJ Nijmegen , The Netherlands
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16
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März M, Kohout M, Neveselý T, Chudoba J, Prukała D, Niziński S, Sikorski M, Burdziński G, Cibulka R. Azodicarboxylate-free esterification with triphenylphosphine mediated by flavin and visible light: method development and stereoselectivity control. Org Biomol Chem 2018; 16:6809-6817. [PMID: 30203820 DOI: 10.1039/c8ob01822g] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Triphenylphosphine (Ph3P) activated by various electrophiles (e.g., alkyl diazocarboxylates) represents an effective mediator of esterification and other nucleophilic substitution reactions. We report herein an aza-reagent-free procedure using flavin catalyst (3-methyl riboflavin tetraacetate), triphenylphosphine, and visible light (448 nm), which allows effective esterification of aromatic and aliphatic carboxylic acids with alcohols. Mechanistic study confirmed that photoinduced electron transfer from triphenylphosphine to excited flavin with the formation of Ph3P˙+ is a crucial step in the catalytic cycle. This allows reactive alkoxyphosphonium species to be generated by reaction of an alcohol with Ph3P˙+ followed by single-electron oxidation. Unexpected stereoselectivity control by the solvent was observed, allowing switching from inversion to retention of configuration during esterification of (S)- or (R)-1-phenylethanol; for example with phenylacetic acid, the ratio shifting from 10 : 90 (retention : inversion) in trifluoromethylbenzene to 99.9 : 0.1 in acetonitrile. Our method uses nitrobenzene to regenerate the flavin photocatalyst. This new approach to flavin re-oxidation has also been successfully proved in benzyl alcohol oxidation, which is a "standard" process among flavin-mediated photooxidations.
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Affiliation(s)
- Michal März
- Department of Organic Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague, Czech Republic.
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17
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Pandey G, Koley S, Talukdar R, Sahani PK. Cross-Dehydrogenating Coupling of Aldehydes with Amines/R-OTBS Ethers by Visible-Light Photoredox Catalysis: Synthesis of Amides, Esters, and Ureas. Org Lett 2018; 20:5861-5865. [DOI: 10.1021/acs.orglett.8b02537] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Ganesh Pandey
- Molecular Synthesis and Drug Discovery Laboratory, Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow-226014, India
| | - Suvajit Koley
- Molecular Synthesis and Drug Discovery Laboratory, Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow-226014, India
| | - Ranadeep Talukdar
- Molecular Synthesis and Drug Discovery Laboratory, Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow-226014, India
| | - Pramod Kumar Sahani
- Molecular Synthesis and Drug Discovery Laboratory, Centre of Biomedical Research, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow-226014, India
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18
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Abstract
Abstract
Thanks to rapid development in the last decades, flavins have been recognized as promising photoactive compounds to design new valuable synthetic methodologies based on photoredox catalysis. The review summarizes general photochemical properties of flavins as well as their early applications in transformations mediated by visible light. Special attention has been paid to the catalyst design for benzylic oxidations as well as to recent flavin applications, for example in E/Z-isomerization, [2+2] cycloaddition, cycloelimination, electrophilic chlorination and sulfide oxidation.
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19
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Jiang B, Xu B, Wang M, Li Z, Liu D, Zhang S. Cobalt(II)/
N
,
N′
,
N′′
‐Trihydroxyisocyanuric Acid Catalyzed Aerobic Oxidative Esterification and Amidation of Aldehydes. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201800118] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Biao‐Lin Jiang
- School of Chemistry and Chemical EngineeringShanxi University Taiyuan 030006 Shanxi China
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex Systems, Institution of Process EngineeringChinese Academy of Sciences Beijing 100190 China
| | - Bao‐Hua Xu
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex Systems, Institution of Process EngineeringChinese Academy of Sciences Beijing 100190 China
| | - Meng‐Liang Wang
- School of Chemistry and Chemical EngineeringShanxi University Taiyuan 030006 Shanxi China
| | - Zeng‐Xi Li
- College of Chemistry and Chemical EngineeringGraduate University of Chinese Academy of Sciences Beijing 100049 China
| | - Dian‐Sheng Liu
- School of Chemistry and Chemical EngineeringShanxi University Taiyuan 030006 Shanxi China
| | - Suo‐Jiang Zhang
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex Systems, Institution of Process EngineeringChinese Academy of Sciences Beijing 100190 China
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20
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Visible light mediated aerobic photocatalytic activation of C H bond by riboflavin tetraacetate and N -hydroxysuccinimide. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.01.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Flavin derivatives immobilized on mesoporous silica: a versatile tool in visible-light photooxidation reactions. MONATSHEFTE FUR CHEMIE 2017. [DOI: 10.1007/s00706-017-2127-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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