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Poderi C, Neira I, Franchi P, Mezzina E, Baù I, Neviani P, Lucarini M. EPR Sensing of a Cation Species by Aza-Crown Ethers Incorporating a Persistent Nitroxidic Radical Unit. Chemistry 2023; 29:e202301508. [PMID: 37435754 DOI: 10.1002/chem.202301508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/13/2023]
Abstract
New nitroxides based on aza-crown ethers were prepared and employed as selective sensors for the detection of inorganic and organic cations by EPR analysis of the corresponding host-guest complexes. The nitroxide unit behaves as a sensitive probe for a number of alkali and alkaline earth metal cations affording EPR spectra differing in the value of nitrogen hyperfine constants and in the appearance of splitted signals due to the non-zero nuclear spin of some metal cation upon complexation. Owing to the remarkable EPR spectral differences between the host and the corresponding cation complex the new macrocycles are likely to act as multitasking tools to recognize several cationic species. EPR behaviour of the larger nitroxide azacrown 1⋅ when acting as a wheel in a radical synthetic bistable [2]rotaxane containing both secondary dialkylammonium and 1,2-bis(pyridinium) molecular stations, was also investigated. Reversible movements of the macrocycle between the two recognition sites in the rotaxane were promptly revealed by EPR, which shows significant changes either in nitrogen coupling constant values (aN ) or in the spectral shape in the two rotaxane co-conformations.
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Affiliation(s)
- Cecilia Poderi
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 83, 40129, Bologna, Italy
| | - Iago Neira
- Departamento de Química, Centro Interdisciplinar de Química y Biología (CICA), Universidade da Coruña, Facultad de Ciencias, Coruña, E-15071A, Spain
| | - Paola Franchi
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 83, 40129, Bologna, Italy
| | - Elisabetta Mezzina
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 83, 40129, Bologna, Italy
| | - Ilario Baù
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 83, 40129, Bologna, Italy
| | - Paolo Neviani
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 83, 40129, Bologna, Italy
| | - Marco Lucarini
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via P. Gobetti 83, 40129, Bologna, Italy
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2
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Abstract
Heteroatom-centered diradical(oid)s have been in the focus of molecular main group chemistry for nearly 30 years. During this time, the diradical concept has evolved and the focus has shifted to the rational design of diradical(oid)s for specific applications. This review article begins with some important theoretical considerations of the diradical and tetraradical concept. Based on these theoretical considerations, the design of diradical(oid)s in terms of ligand choice, steric, symmetry, electronic situation, element choice, and reactivity is highlighted with examples. In particular, heteroatom-centered diradical reactions are discussed and compared with closed-shell reactions such as pericyclic additions. The comparison between closed-shell reactivity, which proceeds in a concerted manner, and open-shell reactivity, which proceeds in a stepwise fashion, along with considerations of diradical(oid) design, provides a rational understanding of this interesting and unusual class of compounds. The application of diradical(oid)s, for example in small molecule activation or as molecular switches, is also highlighted. The final part of this review begins with application-related details of the spectroscopy of diradical(oid)s, followed by an update of the heteroatom-centered diradical(oid)s and tetraradical(oid)s published in the last 10 years since 2013.
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Affiliation(s)
- Alexander Hinz
- Institut für Anorganische Chemie (AOC), Karlsruher Institut für Technologie (KIT), Engesserstrasse 15, 76131 Karlsruhe, Germany
| | - Jonas Bresien
- Institut für Chemie, Universität Rostock, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany
| | - Frank Breher
- Institut für Anorganische Chemie (AOC), Karlsruher Institut für Technologie (KIT), Engesserstrasse 15, 76131 Karlsruhe, Germany
| | - Axel Schulz
- Institut für Chemie, Universität Rostock, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany
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3
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Teslenko FE, Fershtat LL. Unlocking Kuhn Verdazyls: New Synthetic Approach and Useful Mechanistic Insights. Int J Mol Sci 2023; 24:ijms24032693. [PMID: 36769015 PMCID: PMC9916651 DOI: 10.3390/ijms24032693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 02/04/2023] Open
Abstract
An optimized synthetic protocol toward the assembly of Kuhn verdazyls based on an azo coupling of arenediazonium salts with readily available hydrazones followed by the base-mediated cyclization of in situ formed formazans with formalin was developed. The scope and limitations of the presented method were revealed. Some new mechanistic insights on the formation of Kuhn verdazyls were also conducted. It was found that in contradiction with previously assumed hypotheses, the synthesis of verdazyls was accomplished via an intermediate formation of verdazylium cations which were in situ reduced to leucoverdazyls. The latter underwent deprotonation under basic conditions to generate corresponding anions which coproportionate with verdazylium cations to furnish the formation of Kuhn verdazyls. The spectroscopic and electrochemical behavior of the synthesized verdazyls was also studied. Overall, our results may serve as a reliable basis for further investigation in the chemistry and applications of verdazyls.
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Biondi B, Syryamina VN, Rocchio G, Barbon A, Formaggio F, Toniolo C, Raap J, Dzuba SA. Is Cys(MTSL) the Best α-Amino Acid Residue to Electron Spin Labeling of Synthetically Accessible Peptide Molecules with Nitroxides? ACS OMEGA 2022; 7:5154-5165. [PMID: 35187331 PMCID: PMC8851612 DOI: 10.1021/acsomega.1c06227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Electron paramagnetic resonance spectroscopy, particularly its pulse technique double electron-electron resonance (DEER) (also termed PELDOR), is rapidly becoming an extremely useful tool for the experimental determination of side chain-to-side chain distances between free radicals in molecules fundamental for life, such as polypeptides. Among appropriate probes, the most popular are undoubtedly nitroxide electron spin labels. In this context, suitable biosynthetically derived, helical regions of proteins, along with synthetic peptides with amphiphilic properties and antibacterial activities, are the most extensively investigated compounds. A strict requirement for a precise distance measurement has been identified in a minimal dynamic flexibility of the two nitroxide-bearing α-amino acid side chains. To this end, in this study, we have experimentally compared in detail the side-chain mobility properties of the two currently most widely utilized residues, namely, Cys(MTSL) and 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC). In particular, two double-labeled, chemically synthesized 20-mer peptide molecules have been adopted as appropriate templates for our investigation on the determination of the model intramolecular separations. These double-Cys(MTSL) and double-TOAC compounds are both analogues of the almost completely rigid backbone peptide ruler which we have envisaged and 3D structurally analyzed as our original, unlabeled compound. Here, we have clearly found that the TOAC side-chain labels are largely more 3D structurally restricted than the MTSL labels. From this result, we conclude that the TOAC residue offers more precise information than the Cys(MTSL) residue on the side chain-to-side chain distance distribution in synthetically accessible peptide molecules.
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Affiliation(s)
- Barbara Biondi
- Institute
of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
| | - Victoria N. Syryamina
- Institute
of Chemical Kinetics and Combustion, 630090 Novosibirsk, Russian Federation
| | - Gabriele Rocchio
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Antonio Barbon
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Fernando Formaggio
- Institute
of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Claudio Toniolo
- Institute
of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Jan Raap
- Leiden
Institute of Chemistry, Gorlaeus Laboratories,
Leiden University, 2300 RA Leiden, The Netherlands
| | - Sergei A. Dzuba
- Institute
of Chemical Kinetics and Combustion, 630090 Novosibirsk, Russian Federation
- Department
of Physics, Novosibirsk State University, 630090 Novosibirsk, Russian Federation
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5
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Kapuściński S, Anand B, Bartos P, Garcia Fernandez JM, Kaszyński P. Tethered Blatter Radical for Molecular Grafting: Synthesis of 6-Hydroxyhexyloxy, Hydroxymethyl, and Bis(hydroxymethyl) Derivatives and Their Functionalization. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27041176. [PMID: 35208966 PMCID: PMC8876519 DOI: 10.3390/molecules27041176] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 01/30/2022] [Accepted: 02/01/2022] [Indexed: 02/01/2023]
Abstract
Synthetic access to 7-CF3-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl radicals containing 4-(6-hydroxyhexyloxy)phenyl, 4-hydroxymethylphenyl or 3,5-bis(hydroxymethyl)phenyl groups at the C(3) position and their conversion to tosylates and phosphates are described. The tosylates were used to obtain disulfides and an azide with good yields. The Blatter radical containing the azido group underwent a copper(I)-catalyzed azide-alkyne cycloaddition with phenylacetylene under mild conditions, giving the [1,2,3]triazole product in 84% yield. This indicates the suitability of the azido derivative for grafting Blatter radical onto other molecular objects via the CuAAC "click" reaction. The presented derivatives are promising for accessing surfaces and macromolecules spin-labeled with the Blatter radical.
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Affiliation(s)
- Szymon Kapuściński
- Faculty of Chemistry, University of Łódź, Tamka 12, 91-403 Łódź, Poland; (S.K.); (P.B.)
- Centre for Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland;
| | - Bindushree Anand
- Centre for Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland;
| | - Paulina Bartos
- Faculty of Chemistry, University of Łódź, Tamka 12, 91-403 Łódź, Poland; (S.K.); (P.B.)
| | - Jose M. Garcia Fernandez
- Institute for Chemical Research, CSIC, University of Sevilla, Americo Vespucio 49, 41092 Sevilla, Spain
- Correspondence: (J.M.G.F.); (P.K.)
| | - Piotr Kaszyński
- Faculty of Chemistry, University of Łódź, Tamka 12, 91-403 Łódź, Poland; (S.K.); (P.B.)
- Centre for Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland;
- Department of Chemistry, Middle Tennessee State University, Murfreesboro, TN 37132, USA
- Correspondence: (J.M.G.F.); (P.K.)
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6
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Geue N, Winpenny REP, Barran PE. Structural characterisation methods for supramolecular chemistry that go beyond crystallography. Chem Soc Rev 2021; 51:8-27. [PMID: 34817479 DOI: 10.1039/d0cs01550d] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Supramolecular chemistry has grown rapidly over the past three decades, yet synthetic supramolecular chemists still face several challenges when it comes to characterising their compounds. In this review, we present an introduction to structural characterisation techniques commonly used for non-crystalline supramolecular molecules, e.g. nuclear magnetic and electron paramagnetic resonance spectroscopy (NMR and EPR), mass spectrometry (MS), ion mobility mass spectrometry (IM-MS), small-angle neutron and X-ray scattering (SANS and SAXS) as well as cryogenic transmission electron microscopy (cryo-TEM). We provide an overview of their fundamental concepts based on case studies from different fields of supramolecular chemistry, e.g. interlocked structures, molecular self-assembly and host-guest chemistry, while focussing on particular strengths and weaknesses of the discussed methods. Additionally, three multi-technique case studies are examined in detail to illustrate the benefits of using complementary techniques simultaneously.
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Affiliation(s)
- Niklas Geue
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester, M1 7DN, UK.
| | - Richard E P Winpenny
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Perdita E Barran
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, 131 Princess Street, Manchester, M1 7DN, UK.
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7
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Liu Z, Zhang Z, Li T, Zhao W. Three-Dimensional Diradical Metallacage with an Open-Shell Ground State. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Zhaoyue Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan 410082, China
| | - Zhonghui Zhang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan 410082, China
| | - Tao Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan 410082, China
| | - Wanxiang Zhao
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan 410082, China
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8
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Gualandi L, Franchi P, Mezzina E, Goldup SM, Lucarini M. Spin-labelled mechanically interlocked molecules as models for the interpretation of biradical EPR spectra. Chem Sci 2021; 12:8385-8393. [PMID: 34221319 PMCID: PMC8221063 DOI: 10.1039/d1sc01462e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/14/2021] [Indexed: 12/20/2022] Open
Abstract
Biradical spin probes can provide detailed information about the distances between molecules/regions of molecules because the through-space coupling of radical centres, characterised by J, is strongly distance dependent. However, if the system can adopt multiple configurations, as is common in supramolecular complexes, the shape of the EPR spectrum is influenced not only by J but also the rate of exchange between different states. In practice, it is often hard to separate these variables and as a result, the effect of the latter is sometimes overlooked. To demonstrate this challenge unequivocally we synthesised rotaxane biradicals containing nitronyl nitroxide units at the termini of their axles. The rotaxanes exchange between the available biradical conformations more slowly than the corresponding non-interlocked axles but, despite this, in some cases, the EPR spectra of the axle and rotaxane remain remarkably similar. Detailed analysis allowed us to demonstrate that the similar EPR spectral shapes result from different combinations of J and rates of conformational interconversion, a phenomenon suggested theoretically more than 50 years ago. This work reinforces the idea that thorough analysis must be performed when interpreting the spectra of biradicals employed as spin probes in solution.
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Affiliation(s)
- Lorenzo Gualandi
- Department of Chemistry "Giacomo Ciamician", University of Bologna Via San Giacomo 11 Bologna Italy
| | - Paola Franchi
- Department of Chemistry "Giacomo Ciamician", University of Bologna Via San Giacomo 11 Bologna Italy
| | - Elisabetta Mezzina
- Department of Chemistry "Giacomo Ciamician", University of Bologna Via San Giacomo 11 Bologna Italy
| | - Stephen M Goldup
- Department of Chemistry, University of Southampton University Road, Highfield Southampton UK
| | - Marco Lucarini
- Department of Chemistry "Giacomo Ciamician", University of Bologna Via San Giacomo 11 Bologna Italy
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9
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Cantelli A, Franchi P, Mezzina E, Lucarini M. Determination of Binding Strengths of Host‐Guest Complexes in Deep Eutectic Solvents Using Spin Probe Methodology. Chemphyschem 2021; 22:517-521. [DOI: 10.1002/cphc.202001007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/15/2021] [Indexed: 01/04/2023]
Affiliation(s)
- Andrea Cantelli
- Department of Chemistry “G. Ciamician” University of Bologna Via San Giacomo 11 Bologna
| | - Paola Franchi
- Department of Chemistry “G. Ciamician” University of Bologna Via San Giacomo 11 Bologna
| | - Elisabetta Mezzina
- Department of Chemistry “G. Ciamician” University of Bologna Via San Giacomo 11 Bologna
| | - Marco Lucarini
- Department of Chemistry “G. Ciamician” University of Bologna Via San Giacomo 11 Bologna
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10
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Lucarini M. Improving Spin Probe Methodologies to Investigate Supramolecular Assemblies. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901871] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Marco Lucarini
- Department of Chemistry “G. Ciamician”; Alma Mater Studiorum-University of Bologna; Via San Giacomo 11 Bologna Italy
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11
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EPR Spectroscopy: A Powerful Tool to Analyze Supramolecular Host•Guest Complexes of Stable Radicals with Cucurbiturils. Molecules 2020; 25:molecules25040776. [PMID: 32054033 PMCID: PMC7070855 DOI: 10.3390/molecules25040776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/01/2020] [Accepted: 02/07/2020] [Indexed: 01/22/2023] Open
Abstract
Stable organic free radicals are increasingly studied compounds due to the multiple and unusual properties imparted by the single electron(s). However, being paramagnetic, classical methods such as NMR spectroscopy can hardly be used due to relaxation and line broadening effects. EPR spectroscopy is thus better suited to get information about the immediate surroundings of the single electrons. EPR has enabled obtaining useful data in the context of host•guest chemistry, and a classical example is reported here for the stable (2,2,6,6-tetramethyl-4-oxo-piperidin-1-yl)oxyl or 4-oxo-TEMPO nitroxide (TEMPONE) inside the macrocycle host cucurbit[7]uril (CB[7]). Generally and also observed here, a contraction of the spectrum is observed as a result of the reduced nitrogen coupling constant due to inclusion complexation in the hydrophobic cavity of the host. Simulations of EPR spectra allowed determining the corresponding binding constant pointing to a weaker affinity for CB[7], compared to TEMPO with CB[7]. We complement this work by the results of EPR spectroscopy of a biradical: bis-TEMPO-bis-ketal (bTbk) with cucurbit[8]uril (CB[8]). Initial investigations pointed to very weak effects on the spectrum of the guest and incorrectly led us to conclude an absence of binding. However, simulations of EPR spectra combined with NMR data of reduced bTbk allowed showing inclusion complexation. EPR titrations were performed, and the corresponding binding constant was determined. 1H NMR spectra with reduced bTbk suggested a shuttle mechanism, at nearly one equivalent of CB[8], for which the host moves rapidly between two stations.
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12
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Hashimoto H, Inagaki Y, Momma H, Kwon E, Setaka W. Kinetic Stabilization of Carbazole Nitroxides by Inclusion in a Macrocage and Their Electron Spin Resonance Characterization. J Org Chem 2019; 84:11783-11789. [PMID: 31442043 DOI: 10.1021/acs.joc.9b01686] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Some nitroxides, for example, tetramethylpyridiniumoxide, are known as stable radicals; however, carbazole nitroxide is less stable. The kinetic stabilization of labile radicals by introduction of bulky substituents is usually effective to investigate intrinsic properties of the molecule because of small electronic perturbation induced by the substituents. In this study, macrocage molecules with a carbazole nitroxide connected by covalent bonds were newly designed as kinetically stabilized carbazole nitroxides. The nitroxides were prepared and characterized by electron spin resonance spectroscopy. The caged nitroxides presented long half-lives (∼50 h) by kinetic analysis.
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Affiliation(s)
- Hikaru Hashimoto
- Division of Applied Chemistry, Faculty of Urban Environmental Sciences , Tokyo Metropolitan University , Hachioji , Tokyo 192-0397 , Japan
| | - Yusuke Inagaki
- Division of Applied Chemistry, Faculty of Urban Environmental Sciences , Tokyo Metropolitan University , Hachioji , Tokyo 192-0397 , Japan
| | - Hiroyuki Momma
- Research and Analytical Center for Giant Molecules, Graduate School of Science , Tohoku University , Aoba-ku, Sendai 980-8578 , Japan
| | - Eunsang Kwon
- Research and Analytical Center for Giant Molecules, Graduate School of Science , Tohoku University , Aoba-ku, Sendai 980-8578 , Japan
| | - Wataru Setaka
- Division of Applied Chemistry, Faculty of Urban Environmental Sciences , Tokyo Metropolitan University , Hachioji , Tokyo 192-0397 , Japan
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13
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Gualandi L, Franchi P, Credi A, Mezzina E, Lucarini M. EPR sensing of metal and organic cations using a novel spin-labelled dibenzo-24-crown-8-ether. Phys Chem Chem Phys 2019; 21:3558-3563. [PMID: 30229755 DOI: 10.1039/c8cp04362k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The synthesis of novel dibenzo-24-crown ether substituted nitroxides and their use as spin probes for the detection of cation guests by EPR are reported. Formation of a host-guest complex between the proposed spin probes and several cations, both organic and inorganic, was evidenced by a significant change in the value of the benzylic and nitrogen EPR hyperfine splittings upon complexation. This favorable feature provided a reliable EPR sensor that is able to selectively distinguish different cationic guests.
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Affiliation(s)
- Lorenzo Gualandi
- Dipartimento di Chimica "G. Ciamician", University of Bologna, Via San Giacomo 11, 40126, Bologna, Italy.
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14
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15
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Bleve V, Franchi P, Gualandi L, Romano F, Mezzina E, Lucarini M. Synthesis and characterization of a doubly spin-labelled electrochemically driven molecular shuttle. Org Chem Front 2018. [DOI: 10.1039/c8qo00187a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The EPR properties of novel nitroxide-spin-labelled rotaxanes containing a tetrathiafulvalene (TTF) unit and a cyclobis(paraquat-p-phenylene) ring are described.
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Affiliation(s)
- Valentina Bleve
- Department of Chemistry “G. Ciamician” – Alma Mater Studiorum-University of Bologna
- Bologna
- Italy
| | - Paola Franchi
- Department of Chemistry “G. Ciamician” – Alma Mater Studiorum-University of Bologna
- Bologna
- Italy
| | - Lorenzo Gualandi
- Department of Chemistry “G. Ciamician” – Alma Mater Studiorum-University of Bologna
- Bologna
- Italy
| | - Francesco Romano
- Department of Chemistry “G. Ciamician” – Alma Mater Studiorum-University of Bologna
- Bologna
- Italy
| | - Elisabetta Mezzina
- Department of Chemistry “G. Ciamician” – Alma Mater Studiorum-University of Bologna
- Bologna
- Italy
| | - Marco Lucarini
- Department of Chemistry “G. Ciamician” – Alma Mater Studiorum-University of Bologna
- Bologna
- Italy
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16
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Gualandi L, Mezzina E, Franchi P, Lucarini M. Nitroxide Radical Spin Probes for Exploring Halogen-Bonding Interactions in Solution. Chemistry 2016; 22:16017-16021. [DOI: 10.1002/chem.201603394] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Lorenzo Gualandi
- Dipartimento di Chimica “G. Ciamician”; University of Bologna; Via S. Giacomo 11 40126 Bologna Italy
| | - Elisabetta Mezzina
- Dipartimento di Chimica “G. Ciamician”; University of Bologna; Via S. Giacomo 11 40126 Bologna Italy
| | - Paola Franchi
- Dipartimento di Chimica “G. Ciamician”; University of Bologna; Via S. Giacomo 11 40126 Bologna Italy
| | - Marco Lucarini
- Dipartimento di Chimica “G. Ciamician”; University of Bologna; Via S. Giacomo 11 40126 Bologna Italy
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17
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Zanichelli V, Ragazzon G, Arduini A, Credi A, Franchi P, Orlandini G, Venturi M, Lucarini M, Secchi A, Silvi S. Synthesis and Characterization of Constitutionally Isomeric Oriented Calix[6]arene-Based Rotaxanes. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501522] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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18
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Bagryanskaya EG, Krumkacheva OA, Fedin MV, Marque SR. Development and Application of Spin Traps, Spin Probes, and Spin Labels. Methods Enzymol 2015; 563:365-96. [DOI: 10.1016/bs.mie.2015.06.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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