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Wild U, Hübner O, Meiners P, Kaifer E, Enders M, Himmel HJ. Intramolecular Through-Space Double-Electron Transfer Between A Pair of Redox-Active Guanidine Units Aligned by Dithiolate Bridges. Chemistry 2023; 29:e202302418. [PMID: 37606189 DOI: 10.1002/chem.202302418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/22/2023] [Accepted: 08/22/2023] [Indexed: 08/23/2023]
Abstract
Using unconventional synthesis protocols, two redox-active triguanidine units are connected by a dithiolate bridge, aligning the two redox-active units in close proximity. The reduced, neutral and the tetracationic redox states with two dicationic triguanidine units are isolated and fully characterized. Then, the dicationic redox states are prepared by mixing the neutral and tetracationic molecules. At low temperatures, the dications are diamagnetic (singlet ground state) with two different triguanidine units (neutral and dicationic). At room temperature, the triplet state with two radical monocationic triguanidine units is populated. At low temperature (210 K), chemical exchange by intramolecular through-space electron-transfer between the two triguanidine units is evidenced by EXSY NMR spectroscopy. Intramolecular through-space transfer of two electrons from the neutral to the dicationic triguanidine unit is accompanied by migration of the counterions in opposite direction. The rate of double-electron transfer critically depends on the bridge. No electron-transfer is measured in the absence of a bridge (in a mixture of one dicationic and one neutral triguanidine), and relatively slow electron transfer if the bridge does not allow the two triguanidine units to approach each other close enough. The results give detailed, quantitative insight into the factors that influence intramolecular through-space double-electron-transfer processes.
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Affiliation(s)
- Ute Wild
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Olaf Hübner
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Paul Meiners
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Elisabeth Kaifer
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Markus Enders
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Hans-Jörg Himmel
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
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2
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Wild U, Hübner O, Enders M, Kaifer E, Himmel HJ. Connecting Organic Redox‐Active Building Blocks Through Mild Non‐Catalytic C‐H Activation. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ute Wild
- Ruprecht Karls Universitat Heidelberg Fakultat fur Chemie und Geowissenschaften Chemistry GERMANY
| | - Olaf Hübner
- Ruprecht Karls Universitat Heidelberg Fakultat fur Chemie und Geowissenschaften Chemistry GERMANY
| | - Markus Enders
- Ruprecht Karls Universitat Heidelberg Fakultat fur Chemie und Geowissenschaften Chemistry GERMANY
| | - Elisabeth Kaifer
- Ruprecht Karls Universitat Heidelberg Fakultat fur Chemie und Geowissenschaften Chemistry GERMANY
| | - Hans-Jörg Himmel
- Ruprecht-Karls-Universität Heidelberg Institut für Anorganische Chemie Im Neuenheimer Feld 270 69120 Heidelberg GERMANY
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3
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Steuer L, Kaifer E, Himmel HJ. Redox‐Active Dendrimer‐Like Oligoguanidines and Their Use in a Proton‐Coupled Electron Transfer Reaction. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Lena Steuer
- Ruprecht Karls Universitat Heidelberg Fakultat fur Chemie und Geowissenschaften Chemistry GERMANY
| | - Elisabeth Kaifer
- Ruprecht Karls Universitat Heidelberg Fakultat fur Chemie und Geowissenschaften Chemistry GERMANY
| | - Hans-Jörg Himmel
- Ruprecht-Karls-Universität Heidelberg Institut für Anorganische Chemie Im Neuenheimer Feld 270 69120 Heidelberg GERMANY
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Walter P, Hübner O, Kaifer E, Himmel HJ. Proton-Coupled Electron Transfer (PCET) with 1,4-Bisguanidino-Benzene Derivatives: Comparative Study and Use in Acid-Initiated C-H Activation. Chemistry 2021; 27:11943-11956. [PMID: 34132428 PMCID: PMC8457230 DOI: 10.1002/chem.202101539] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Indexed: 11/18/2022]
Abstract
Proton‐coupled electron transfer (PCET) is of key importance in modern synthetic chemistry. Redox‐active guanidines were established by our group as valuable alternatives to toxic high‐potential benzoquinones in a variety of different PCET reactions. In this work, the PCET reactivity of a series of 1,4‐bisguanidino‐benzenes varying in their redox potentials and proton affinities is evaluated. The relevant redox and protonation states are fully characterized, and the compounds sorted with respect to their PCET reactivity by comparative PCET experiments supplemented by quantum‐chemical calculations. Depending on the studied reactions, the driving force is either electron transfer or proton transfer; thereby the influence of both processes on the overall reactivity could be assessed. Then, two of the PCET reagents are applied in representative oxidative aryl‐aryl coupling reactions, namely the intramolecular coupling of 3,3’’‐4,4’’‐tetramethoxy‐o‐terphenyl to give the corresponding triphenylene, the intermolecular coupling of N‐ethylcarbazole to give N,N’‐diethyl‐3,3’‐bicarbazole, and in the oxidative lactonization of 2‐[(4‐methoxyphenyl)methyl]‐benzoic acid. Under mild conditions, the reactions proceed fast and efficient. Only small amounts of acid are needed, in clear contrast to the corresponding coupling reactions with traditional high‐potential benzoquinones such as DDQ or chloranil requiring a large excess of a strong acid.
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Affiliation(s)
- Petra Walter
- Inorganic Chemistry, Ruprecht-Karls University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Olaf Hübner
- Inorganic Chemistry, Ruprecht-Karls University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Elisabeth Kaifer
- Inorganic Chemistry, Ruprecht-Karls University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Hans-Jörg Himmel
- Inorganic Chemistry, Ruprecht-Karls University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
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Steuer L, Kaifer E, Himmel HJ. On the metal-ligand bonding in dinuclear complexes with redox-active guanidine ligands. Dalton Trans 2021; 50:9467-9482. [PMID: 34136887 DOI: 10.1039/d1dt01354h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Coordination compounds with redox-active ligands are currently intensively studied. Within this research theme, redox-active guanidines have been established as a new, eminent class of redox-active ligands. In this work the variation of metal-guanidine bonding in dinuclear transition metal complexes with bridging redox-active tetrakisguanidine ligands is analysed. A series of dinuclear complexes with different metals (Mn, Fe, Co, Ni, Cu and Zn) is synthesized, using either newly prepared redox-active tetrakisguanidino-dioxine or previously reported tetrakisguanidino-benzene ligands. The discussion of the bond properties in this work is predominantly based on the trends of structural parameters, derived from determination of single-crystal structures by X-ray diffraction and quantum chemical calculations. In addition, the trends in the redox potentials and magnetometric (SQUID) measurements on some of the complexes are included. Due to their combined σ- and π-electron donor capability, redox-active guanidine ligands are weak-field ligands; the σ- and π-bonding contributions vary with the metal. The results highlight the peculiarity of copper-guanidine bonding with a high π-bond contribution to metal-guanidine bonding, enabled by structural distortion of the coordination mode from tetrahedral in the direction of square-planar, short copper-guanidine bonds and minor displacement of the copper atoms from the ligand aromatic plane.
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Affiliation(s)
- Lena Steuer
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
| | - Elisabeth Kaifer
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
| | - Hans-Jörg Himmel
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
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6
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Wild U, Walter P, Hübner O, Kaifer E, Himmel H. Evaluation of the Synthetic Scope and the Reaction Pathways of Proton-Coupled Electron Transfer with Redox-Active Guanidines in C-H Activation Processes. Chemistry 2020; 26:16504-16513. [PMID: 32893902 PMCID: PMC7756729 DOI: 10.1002/chem.202003424] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/04/2020] [Indexed: 11/28/2022]
Abstract
Proton-coupled electron transfer (PCET) is currently intensively studied because of its importance in synthetic chemistry and biology. In recent years it was shown that redox-active guanidines are capable PCET reagents for the selective oxidation of organic molecules. In this work, the scope of their PCET reactivity regarding reactions that involve C-H activation is explored and kinetic studies carried out to disclose the reaction mechanisms. Organic molecules with potential up to 1.2 V vs. ferrocenium/ferrocene are efficiently oxidized. Reactions are initiated by electron transfer, followed by slow proton transfer from an electron-transfer equilibrium.
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Affiliation(s)
- Ute Wild
- Institut für Anorganische ChemieRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Petra Walter
- Institut für Anorganische ChemieRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Olaf Hübner
- Institut für Anorganische ChemieRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Elisabeth Kaifer
- Institut für Anorganische ChemieRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Hans‐Jörg Himmel
- Institut für Anorganische ChemieRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
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Kantlehner W, Tiritiris I, Vettel M, Frey W. Orthoamide und Iminiumsalze, IIC. Darstellung von N-( ω-Ammonioalkyl)- N,N′,N′,N″,N″-peralkylierten Guanidiniumsalzen und N-( ω-Aminoalkyl)- N′,N′,N″,N″-tetramethylguanidinen. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2020. [DOI: 10.1515/znb-2019-0229] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
N,N,N′,N′-Tetraalkylchlorformamidiniumchlorides 1a, b react with ω-dimethylaminoalkylamines 19, 20 to give mixtures of N-(ω-dimethylammonioalkyl)-guanidinium salts 12, 13 and N-(ω-dimethylaminoalkyl)-guanidinium salts 21, 22. These mixtures are transformed to mixtures of the ureas 15, 17 and N-(ω-dimethylaminoalkyl)-guanidines 23, 25 on treatment with aqueous sodium hydroxide. The reaction of N-(3-dimethylammoniopropyl)-guanidin 25a with dimethylsulfate in a molar ratio of 1:1 delivers a mixture of the N-(3-dimethylaminopropyl)-N,N,N′,N′,N″,N″-pentamethyl-guanidinium salt 29a and the N-(3-dimethylammoniopropyl)-N,N′,N′,N″,N″-pentamethyl-guanidinium-bis (methylsulfate) 33a. The action of dimethylsulfate on the guanidines 23a, 25a in a molar ratio of 2:1 affords the bisquarternary salts 32a, 33a. Alkylating reagents as methyliodide, benzylbromide, allylbromide and chloroacetonitrile attack N-(2-dimethylaminoethyl)-N′,N′,N″,N″-tetraethylguanidine (23b) in a molar ratio of 1:1 cleanly at the dimethylaminoethylgroup to give the ammonium salts 30a–d. As a strong base the guanidine 23b dehydrochlorinates β-Chlorpropionitrile and chloroacetone under formation of the guanidinium salt 21c. In contrast to this the reaction of ethyl bromoacetate with the N-(2-dimethylaminoethyl)guanidine 23b occurs at the guanidinogroup giving the guanidinium salt 28c. The methylation of the guanidinium chlorides 21a, 22a with dimethyl sulfate affords the bis-quaternary salts 35b, 36b with mixed anions. From the heterocyclic guanidines 14, 16 and the alkylating reagents benzylbromide and ethyl bromoacetate the heterocyclic guanidinium salts 37a, b, 39a, b can be obtained. The reactions with ethyl chloroformiate proceed in an analogous way giving the guanidinium salts 37c, 39c. The N-alkyl-N,N,N′,N′-tetramethyl-(3-ureidopropyl)guanidinium salts 41a, b can be prepared from the N′,N′,N″,N″-tetramethyl-N′′-(3-ureidopropyl) guanidine 17a and the alkylating compounds dimethyl sulfate and benzyl bromide. Several compounds obtained that way were transformed to the corresponding tetraphenyloborates and bis(tetraphenylborates), respectively.
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Affiliation(s)
- Willi Kantlehner
- Institut für Angewandte Forschung, Abteilung Technische Organische Synthesechemie und Katalyseforschung (TOSKA), Hochschule Aalen , Beethovenstr. 1 , D-73430 Aalen , Germany
- Institut für Organische Chemie, Universität Stuttgart , Pfaffenwaldring 55 , 70569 Stuttgart , Germany
| | - Ioannis Tiritiris
- Institut für Organische Chemie, Universität Stuttgart , Pfaffenwaldring 55 , 70569 Stuttgart , Germany
| | - Markus Vettel
- Institut für Organische Chemie, Universität Stuttgart , Pfaffenwaldring 55 , 70569 Stuttgart , Germany
| | - Wolfgang Frey
- Institut für Organische Chemie, Universität Stuttgart , Pfaffenwaldring 55 , 70569 Stuttgart , Germany
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8
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Wagner C, Kreis F, Popp D, Hübner O, Kaifer E, Himmel H. 1,2,4,5-Tetrakis(tetramethylguanidino)-3,6-diethynyl-benzenes: Fluorescent Probes, Redox-Active Ligands and Strong Organic Electron Donors. Chemistry 2020; 26:10336-10347. [PMID: 32368816 PMCID: PMC7497081 DOI: 10.1002/chem.202001557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/30/2020] [Indexed: 11/25/2022]
Abstract
In this work, the change of reactivity induced by the introduction of two para-ethynyl substituents (CCSi(iPr)3 or CCH) to the organic electron-donor 1,2,4,5-tetrakis(tetramethylguanidino)-benzene is evaluated. The redox-properties and redox-state dependent fluorescence are evaluated, and dinuclear CuI and CuII complexes synthesized. The Lewis-acidic B(C6 F5 )3 substitutes the proton of the ethynyl -CCH groups to give new anionic -CCB(C6 F5 )3 - substituents, leading eventually to a novel dianionic strong electron donor in its diprotonated form. Its two-electron oxidation with dioxygen in the presence of a copper catalyst yields the first redox-active guanidine that is neutral (instead of cationic) in its oxidized form.
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Affiliation(s)
- Conrad Wagner
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Franka Kreis
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Dennis Popp
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Olaf Hübner
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Elisabeth Kaifer
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Hans‐Jörg Himmel
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
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Wild U, Hübner O, Himmel H. Redox-Active Guanidines in Proton-Coupled Electron-Transfer Reactions: Real Alternatives to Benzoquinones? Chemistry 2019; 25:15988-15992. [PMID: 31535741 PMCID: PMC7065378 DOI: 10.1002/chem.201903438] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Indexed: 01/24/2023]
Abstract
Guanidino-functionalized aromatics (GFAs) are readily available, stable organic redox-active compounds. In this work we apply one particular GFA compound, 1,2,4,5-tetrakis(tetramethylguanidino)benzene, in its oxidized form in a variety of oxidation/oxidative coupling reactions to demonstrate the scope of its proton-coupled electron transfer (PCET) reactivity. Addition of an excess of acid boosts its oxidation power, enabling the oxidative coupling of substrates with redox potentials of at least +0.77 V vs. Fc+ /Fc. The green recyclability by catalytic re-oxidation with dioxygen is also shown. Finally, a direct comparison indicates that GFAs are real alternatives to toxic halo- or cyano-substituted benzoquinones.
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Affiliation(s)
- Ute Wild
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Olaf Hübner
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Hans‐Jörg Himmel
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
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10
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Walter P, Kaifer E, Herrmann H, Wadepohl H, Hübner O, Himmel H. Redox‐Active Guanidines with One or Two Guanidino Groups and Their Integration in Low‐Dimensional Perovskite Structures. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900975] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Petra Walter
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Elisabeth Kaifer
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Hendrik Herrmann
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Hubert Wadepohl
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Olaf Hübner
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Hans‐Jörg Himmel
- Anorganisch‐Chemisches Institut Ruprecht‐Karls‐Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
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11
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ADUC Prizes 2019: L. Greb, T.‐C. Jagau, and M. van Gemmeren / Ignaz L. Lieben Award: N. Maulide. Angew Chem Int Ed Engl 2019; 58:3687. [DOI: 10.1002/anie.201901554] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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ADUC‐Preise 2019: L. Greb, T.‐C. Jagau und M. van Gemmeren / Ignaz L. Lieben‐Preis: N. Maulide. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201901554] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Wagner C, Hübner O, Kaifer E, Himmel HJ. Probing the Proton-Coupled Electron-Transfer (PCET) Reactivity of a Cross-Conjugated Cruciform Chromophore by Redox-State-Dependent Fluorescence. Chemistry 2019; 25:3781-3785. [PMID: 30688382 DOI: 10.1002/chem.201900268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Indexed: 11/07/2022]
Abstract
Proton-coupled electron transfer (PCET) reactions are of great importance in synthetic chemistry and in biology, but the acquisition of kinetic information for these reactions is often difficult. Herein, we report the synthesis of a new PCET reagent, showing redox-state dependent fluorescence, by merging the concept of cross-conjugated cruciform chromophores with the strategy of imposing redox activity and Brønsted basicity to aromatic compounds by substitution with guanidino groups. The compound is isolated and characterized in all stable states-reduced, twofold and fourfold protonated and twofold oxidized-and then applied in PCET reactions by using its redox-state dependent fluorescence signal for kinetic measurements.
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Affiliation(s)
- Conrad Wagner
- Anorganisch-Chemisches Institut, Ruprecht-Karls-University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Olaf Hübner
- Anorganisch-Chemisches Institut, Ruprecht-Karls-University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Elisabeth Kaifer
- Anorganisch-Chemisches Institut, Ruprecht-Karls-University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Hans-Jörg Himmel
- Anorganisch-Chemisches Institut, Ruprecht-Karls-University of Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
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14
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Li H, Guo YH, Wu JY, Zhang MT. Proton-coupled electron transfer oxidation of O–H bond by the N-radical cation of Wurster's blue salt (TMPDA˙ +). Chem Commun (Camb) 2019; 55:3465-3468. [DOI: 10.1039/c9cc00354a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Beyond a single electron oxidant, the N-radical cation is also a good PCET reagent.
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Affiliation(s)
- Han Li
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University
- Beijing
- China
| | - Yu-Hua Guo
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University
- Beijing
- China
| | - Jun-Yan Wu
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University
- Beijing
- China
| | - Ming-Tian Zhang
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University
- Beijing
- China
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