1
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Agou T, Kuroiwa S, Fukumoto H, Nabeshima T. Synthesis and optical properties of antimony(V) complexes of a trianionic N 2O 2-type tetradentate dipyrrin ligand. Chem Commun (Camb) 2024; 60:4557-4560. [PMID: 38572576 DOI: 10.1039/d4cc00630e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
LSbCl2, an air- and moisture-stable antimony(V)-dipyrrin complex at room temperature, was obtained by treating an excess amount (20 eq.) of SbCl3 with a trianionic N2O2-type tetradentate dipyrrin ligand (L) under visible-light irradiation and O2 atmosphere. The Cl ligands in LSbCl2 were replaced by OH ligands via hydrolysis, yielding LSb(OH)2. Further, the molecular structures and optical properties of the Sb(V)-dippyrin complexes were investigated. While LSbCl2 was non-fluorescent, LSb(OH)2 exhibited an intense red fluorescence with a photoluminescence quantum yield of 68%.
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Affiliation(s)
- Tomohiro Agou
- Department of Material Science, Graduate School of Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan.
| | - Shunsuke Kuroiwa
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Naka-narusawa, Hitachi, Ibaraki 316-8511, Japan.
| | - Hiroki Fukumoto
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Naka-narusawa, Hitachi, Ibaraki 316-8511, Japan.
| | - Tatsuya Nabeshima
- Institute of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan.
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2
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Rowan JA, Rudd SE, Ganio K, McDevitt CA, White JM, Donnelly PS. Copper(II) Complexes of 2,2'- Bisdipyrrins: Synthesis, Characterization, Cell Uptake, and Radiolabeling with Copper-64. Inorg Chem 2023; 62:20666-20676. [PMID: 37552883 DOI: 10.1021/acs.inorgchem.3c01551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Complexes prepared with positron-emitting copper-64 are of interest as imaging agents for positron emission tomography (PET). This work investigates the potential of using acyclic tetrapyrrolic 2,2'-bisdipyrrins as ligands to prepare charge-neutral, lipophilic, cell-permeable, redox active complexes with positron-emitting copper-64. The synthesis and characterization of a series of tetrapyrrolic 2,2'-bisdipyrrin copper(II) complexes are reported. Four 2,2'-bisdipyrrin copper(II) complexes were prepared with different functional groups in the meso-position of the ligands. Two of the new copper(II) complexes, one palladium(II) complex, and one nickel(II) complex were characterized by X-ray crystallography, which demonstrated that the copper(II) is in a distorted square planar environment. An investigation of the electrochemical properties of the complexes by cyclic voltammetry revealed that the complexes undergo multiple quasi-reversible processes. A comparison of the cyclic voltammetry of the copper complexes with their palladium(II) analogues suggests that these redox processes are ligand-based and not metal-based. The copper(II) complexes are cell-permeable in A431 mammalian cells and are nontoxic at concentrations of 50 μM. The ligands can be radiolabeled with copper-64 at room temperature.
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Affiliation(s)
- Jacob A Rowan
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Stacey E Rudd
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Katherine Ganio
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Christopher A McDevitt
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Jonathan M White
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Paul S Donnelly
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
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3
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Carsch KM, North SC, DiMucci IM, Iliescu A, Vojáčková P, Khazanov T, Zheng SL, Cundari TR, Lancaster KM, Betley TA. Nitrene transfer from a sterically confined copper nitrenoid dipyrrin complex. Chem Sci 2023; 14:10847-10860. [PMID: 37829016 PMCID: PMC10566472 DOI: 10.1039/d3sc03641c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 09/04/2023] [Indexed: 10/14/2023] Open
Abstract
Despite the myriad Cu-catalyzed nitrene transfer methodologies to form new C-N bonds (e.g., amination, aziridination), the critical reaction intermediates have largely eluded direct characterization due to their inherent reactivity. Herein, we report the synthesis of dipyrrin-supported Cu nitrenoid adducts, investigate their spectroscopic features, and probe their nitrene transfer chemistry through detailed mechanistic analyses. Treatment of the dipyrrin CuI complexes with substituted organoazides affords terminally ligated organoazide adducts with minimal activation of the azide unit as evidenced by vibrational spectroscopy and single crystal X-ray diffraction. The Cu nitrenoid, with an electronic structure most consistent with a triplet nitrene adduct of CuI, is accessed following geometric rearrangement of the azide adduct from κ1-N terminal ligation to κ1-N internal ligation with subsequent expulsion of N2. For perfluorinated arylazides, stoichiometric and catalytic C-H amination and aziridination was observed. Mechanistic analysis employing substrate competition reveals an enthalpically-controlled, electrophilic nitrene transfer for primary and secondary C-H bonds. Kinetic analyses for catalytic amination using tetrahydrofuran as a model substrate reveal pseudo-first order kinetics under relevant amination conditions with a first-order dependence on both Cu and organoazide. Activation parameters determined from Eyring analysis (ΔH‡ = 9.2(2) kcal mol-1, ΔS‡ = -42(2) cal mol-1 K-1, ΔG‡298K = 21.7(2) kcal mol-1) and parallel kinetic isotope effect measurements (1.10(2)) are consistent with rate-limiting Cu nitrenoid formation, followed by a proposed stepwise hydrogen-atom abstraction and rapid radical recombination to furnish the resulting C-N bond. The proposed mechanism and experimental analysis are further corroborated by density functional theory calculations. Multiconfigurational calculations provide insight into the electronic structure of the catalytically relevant Cu nitrene intermediates. The findings presented herein will assist in the development of future methodology for Cu-mediated C-N bond forming catalysis.
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Affiliation(s)
- Kurtis M Carsch
- Department of Chemistry and Chemical Biology, Harvard University Cambridge MA 02138 USA
| | - Sasha C North
- Center for Advanced Scientific Computing and Modeling (CASCaM), Department of Chemistry, University of North Texas, Denton TX 76203 USA
| | - Ida M DiMucci
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University Ithaca New York 14853 USA
| | - Andrei Iliescu
- Department of Chemistry and Chemical Biology, Harvard University Cambridge MA 02138 USA
| | - Petra Vojáčková
- Department of Chemistry and Chemical Biology, Harvard University Cambridge MA 02138 USA
| | - Thomas Khazanov
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University Ithaca New York 14853 USA
| | - Shao-Liang Zheng
- Department of Chemistry and Chemical Biology, Harvard University Cambridge MA 02138 USA
| | - Thomas R Cundari
- Center for Advanced Scientific Computing and Modeling (CASCaM), Department of Chemistry, University of North Texas, Denton TX 76203 USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University Ithaca New York 14853 USA
| | - Theodore A Betley
- Department of Chemistry and Chemical Biology, Harvard University Cambridge MA 02138 USA
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4
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Korzun A, Crespi S, Golz C, Bismuto A. Replacing the BO in BODIPY: unlocking the path to SBDIPY and BIDIPY chromophores. Chem Sci 2023; 14:6579-6584. [PMID: 37350824 PMCID: PMC10284139 DOI: 10.1039/d3sc01493b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/28/2023] [Indexed: 06/24/2023] Open
Abstract
Boron-based dipyrrin chromophores (BODIPY) have found widespread application over the last twenty years in fields as diverse as medicine and materials. Thus, several efforts have been placed to exchange boron with other elements, with the aim of developing materials with complementary luminescent properties. However, despite these attempts, the incorporation of other main-group elements in dipyrrin scaffolds remains still rare. We have successfully synthesized and characterized novel chromophores based on antimony and bismuth, SBDIPY and BIDIPY. Solution stabilities have been investigated by VT-UV/vis spectroscopy and the fluorescence emission studied and supported by computational analysis. We were also able to isolate the first direct analogue of BODIPY containing fluoride handles, disclosing preliminary luminescent features.
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Affiliation(s)
- André Korzun
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen Tammannstr. 2 37077 Göttingen Germany
| | - Stefano Crespi
- Department of Chemistry - Ångström Laboratory Uppsala University Box 523, 751 20 Uppsala Sweden
| | - Christopher Golz
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen Tammannstr. 2 37077 Göttingen Germany
| | - Alessandro Bismuto
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen Tammannstr. 2 37077 Göttingen Germany
- Institut für Anorganische Chemie Gerhard-Domagk-Straße 1 53121 Bonn Germany
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5
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Pushpanandan P, Behera KC, Ravikanth M. Pd(II), Ni(II), and Cu(II) complexes of α,α'-ditolylmethanone dipyrroethene. Dalton Trans 2023; 52:6882-6889. [PMID: 37157997 DOI: 10.1039/d3dt00476g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Dipyrromethenes containing two pyrrole rings connected by one meso-carbon are versatile monoanionic bidentate ligands and form coordination complexes with many metals/nonmetals/metalloids. Dipyrroethenes containing one additional meso-carbon compared to dipyrromethenes have more space between coordinating pyrrole nitrogens and provide a good coordination environment but have not been explored as ligands in coordination chemistry. Dipyrroethenes are dianionic bidentate ligands and by suitable modifications, the coordination environment of dipyrroethenes can be changed further. Herein, we successfully synthesized α,α'-ditolylmethanone dipyrroethene which is a bipyrrolic tetradentate ligand with an ONNO ligand core and used it for the synthesis of novel Pd(II), Ni(II), and Cu(II) metal complexes by treating it with respective metal salts in CH2Cl2/CH3OH at room temperature. The X-ray crystallographic structure of the metal complexes showed that the M(II) ion was coordinated to the ONNO atoms of the ligand in a perfect square planar geometry. The NMR studies of Pd(II) and Ni(II) complexes also supported the highly symmetric nature of the metal complexes. The absorption spectra of the metal complexes showed strong bands in the region of 300-550 nm. The electrochemical studies of metal complexes revealed that only ligand-based oxidation and reduction were observed. The DFT and TD-DFT studies were in agreement with the experimental observations. Our preliminary studies indicated that the Pd(II) complex can be used as a catalyst for the Fujiwara-Moritani olefination reaction.
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6
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Wu D, Durán-Sampedro G, Fitzgerald S, Garre M, O'Shea DF. Double click macrocyclization with Sondheimer diyne of aza-dipyrrins for B-F ree bioorthogonal imaging. Chem Commun (Camb) 2023; 59:1951-1954. [PMID: 36722871 DOI: 10.1039/d2cc06461h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Sequential azide/diyne cycloadditions proved highly effective for the macrocyclization of a bis-azido aza-dipyrrin. Macrocyclic aza-dipyrrin could be produced in 30 min at rt in water with changes in fluorescence intensity and lifetimes measurable upon reaction. Live cell microscopy showed that aza-dipyrrins were suitable for confocal and STED super-resolution imaging and a bioorthogonal response to macrocyclization could be detected in cellular compartments. These results will encourage a broader examination of the sensing and imaging uses of aza-dipyrrins.
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Affiliation(s)
- Dan Wu
- Department of Chemistry, RCSI, 123 St Stephen's Green, Dublin 2, Ireland.
| | | | - Sheila Fitzgerald
- Department of Chemistry, RCSI, 123 St Stephen's Green, Dublin 2, Ireland.
| | - Massimiliano Garre
- Department of Chemistry, RCSI, 123 St Stephen's Green, Dublin 2, Ireland.
| | - Donal F O'Shea
- Department of Chemistry, RCSI, 123 St Stephen's Green, Dublin 2, Ireland.
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7
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Avan İ, Kani İ, Çalıkuşu L. Bis(dipyrrinato)zinc(II) Complexes: Synthesis and catalytic activity towards alcohol oxidation. INORG CHEM COMMUN 2023. [DOI: 10.1016/j.inoche.2023.110518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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8
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van Rees K, Rajeshkumar T, Maron L, Sproules S, Love JB. Role of the Meso Substituent in Defining the Reduction of Uranyl Dipyrrin Complexes. Inorg Chem 2022; 61:20424-20432. [PMID: 36472325 PMCID: PMC9768749 DOI: 10.1021/acs.inorgchem.2c03048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The uranyl complex UVIO2Cl(LMes) of the redox-active, acyclic dipyrrin-diimine anion LMes- [HLMes = 1,9-di-tert-butyl-imine-5-(mesityl)dipyrrin] is reported, and its redox property is explored and compared with that of the previously reported UVIO2Cl(LF) [HLF = 1,9-di-tert-butyl-imine-5-(pentafluorophenyl)dipyrrin] to understand the influence of the meso substituent. Cyclic voltammetry, electron paramagnetic resonance spectroscopy, and density functional theory studies show that the alteration from an electron-withdrawing meso substituent to an electron-donating meso substituent on the dipyrrin ligand significantly modifies the stability of the products formed after reduction. For UVIO2Cl(LMes), the formation of a diamond-shaped, oxo-bridged uranyl(V) dimer, [UVO2(LMes)]2 is seen, whereas in contrast, for UVIO2Cl(LF), only ligand reduction occurs. Computational modeling of these reactions shows that while ligand reduction followed by chloride dissociation occurs in both cases, ligand-to-metal electron transfer is favorable for UVIO2Cl(LMes) only, which subsequently facilitates uranyl(V) dimerization.
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Affiliation(s)
- Karlotta van Rees
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, U.K.
| | - Thayalan Rajeshkumar
- LPCNO,
INSA, Université de Toulouse, 135, Avenue de Rangueil, Toulouse Cedex 4 31077, France
| | - Laurent Maron
- LPCNO,
INSA, Université de Toulouse, 135, Avenue de Rangueil, Toulouse Cedex 4 31077, France
| | - Stephen Sproules
- WestCHEM
School of Chemistry, University of Glasgow, Glasgow G12 8QQ, U.K.
| | - Jason B. Love
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, U.K.,
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9
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Aksenova I, Pomogaev V. Stability of Dibromo-Dipyrromethene Complexes Coordinated with B, Zn, and Cd in Solutions of Various Acidities. Molecules 2022; 27:molecules27248815. [PMID: 36557945 PMCID: PMC9784619 DOI: 10.3390/molecules27248815] [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: 11/30/2022] [Revised: 12/08/2022] [Accepted: 12/08/2022] [Indexed: 12/15/2022] Open
Abstract
The spectral luminescent properties of dipyrromethenates halogenated with bromine on both ends of the long axis and coordinated using boron fluoride, zinc, or cadmium in neutral ethanol and acidified with hydrochloric acid solutions were studied. The constants of the acid-base equilibrium of the complexes in the proton-donor solvents in the ground and excited states was determined. The mechanisms of complex protonation were discussed, depending on the structure of the compounds. The electronic structures of the neutral and protonated compounds were modeled and analyzed based on the quantum-chemical method. The structures and spectral-luminescence properties were calculated using the SMD model of ethanol solvent using the TD-DFT theory with the B3LYP functional and the composite def2-SVP/def2-TZVP/def2-TZVPP_ECP basis sets, depending on the atomic number of the elements.
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10
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Teeuwen PCP, Melissari Z, Senge MO, Williams RM. Metal Coordination Effects on the Photophysics of Dipyrrinato Photosensitizers. Molecules 2022; 27:molecules27206967. [PMID: 36296559 PMCID: PMC9610856 DOI: 10.3390/molecules27206967] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/10/2022] [Accepted: 10/13/2022] [Indexed: 11/16/2022] Open
Abstract
Within this work, we review the metal coordination effect on the photophysics of metal dipyrrinato complexes. Dipyrrinato complexes are promising candidates in the search for alternative transition metal photosensitizers for application in photodynamic therapy (PDT). These complexes can be activated by irradiation with light of a specific wavelength, after which, cytotoxic reactive oxygen species (ROS) are generated. The metal coordination allows for the use of the heavy atom effect, which can enhance the triplet generation necessary for generation of ROS. Additionally, the flexibility of these complexes for metal ions, substitutions and ligands allows the possibility to tune their photophysical properties. A general overview of the mechanism of photodynamic therapy and the properties of the triplet photosensitizers is given, followed by further details of dipyrrinato complexes described in the literature that show relevance as photosensitizers for PDT. In particular, the photophysical properties of Re(I), Ru(II), Rh(III), Ir(III), Zn(II), Pd(II), Pt(II), Ni(II), Cu(II), Ga(III), In(III) and Al(III) dipyrrinato complexes are discussed. The potential for future development in the field of (dipyrrinato)metal complexes is addressed, and several new research topics are suggested throughout this work. We propose that significant advances could be made for heteroleptic bis(dipyrrinato)zinc(II) and homoleptic bis(dipyrrinato)palladium(II) complexes and their application as photosensitizers for PDT.
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Affiliation(s)
- Paula C. P. Teeuwen
- Molecular Photonics Group, Van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands
| | - Zoi Melissari
- Molecular Photonics Group, Van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands
- Medicinal Chemistry, Trinity Translational Medicine Institute, Trinity Centre for Health Sciences, Trinity College Dublin, The University of Dublin St James’s Hospital, D08 RX0X Dublin, Ireland
| | - Mathias O. Senge
- Medicinal Chemistry, Trinity Translational Medicine Institute, Trinity Centre for Health Sciences, Trinity College Dublin, The University of Dublin St James’s Hospital, D08 RX0X Dublin, Ireland
- Institute for Advanced Study (TUM-IAS), Technical University of Munich, Lichtenberg-Str. 2a, 85748 Garching, Germany
- Correspondence: (M.O.S.); (R.M.W.)
| | - René M. Williams
- Molecular Photonics Group, Van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands
- Correspondence: (M.O.S.); (R.M.W.)
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11
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El Khatib M, Cheprakov AV, Vinogradov SA. Unusual Reactivity and Metal Affinity of Water-Soluble Dipyrrins. Inorg Chem 2022; 61:12746-12758. [PMID: 35917291 PMCID: PMC10178602 DOI: 10.1021/acs.inorgchem.2c01834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dipyrrins are a versatile class of organic ligands capable of fluorogenic complexation of metal ions. The primary goal of our study was to evaluate dipyrrins functionalized with ester and amide groups in 2,2'-positions in sensing applications. While developing the synthesis, we found that 3,3',4,4'-tetraalkyldipyrrins 2,2'-diesters as well as 2,2'-diamides can undergo facile addition of water at the meso-bridge, transforming into colorless meso-hydroxydipyrromethanes. Spectroscopic and computational investigation revealed that this transformation proceeds via dipyrrin cations, which exist in equilibrium with the hydroxydipyrromethanes. While trace amounts of acid favor conversion of dipyrrins to hydroxydipyrromethanes, excess acid shifts the equilibrium toward the cations. Similarly, the presence of Zn2+ facilitates elimination of water from hydroxydipyrromethanes with chromogenic regeneration of the dipyrrin system. In organic solutions in the presence of Zn2+, dipyrrin-2,2'-diesters exist as mixtures of mono-(LZnX) and bis-(L2Zn) complexes. In L2Zn, the dipyrrin ligands are oriented in a nonorthogonal fashion, causing strong exciton coupling. In aqueous solutions, dipyrrins bind Zn2+ in a 1:1 stoichiometry, forming mono-dipyrrinates (LZnX). Unexpectedly, dipyrrins with more electron-rich 2,2'-carboxamide groups revealed ∼20-fold lower affinity for Zn2+ than the corresponding 2,2'-diesters. Density Functional Theory (DFT) calculations with explicit inclusion of water reproduced the observed trends and allowed us to trace the low affinity of the dipyrrin-diamides to the stabilization of the corresponding free bases via hydrogen bonding with water molecules. Overall, our results reveal unusual trends in the reactivity of dipyrrins and provide clues for the design of dipyrrin-based sensors for biological applications.
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12
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Toganoh M, Furuta H. Creation from Confusion and Fusion in the Porphyrin World─The Last Three Decades of N-Confused Porphyrinoid Chemistry. Chem Rev 2022; 122:8313-8437. [PMID: 35230807 DOI: 10.1021/acs.chemrev.1c00065] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Confusion is a novel concept of isomerism in porphyrin chemistry, delivering a steady stream of new chemistry since the discovery of N-confused porphyrin, a porphyrin mutant, in 1994. These days, the number of confused porphyrinoids is increasing, and confusion and associated fusion are found in various fields such as supramolecular chemistry, materials chemistry, biological chemistry, and catalysts. In this review, the birth and growth of confused porphyrinoids in the last three decades are described.
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Affiliation(s)
- Motoki Toganoh
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hiroyuki Furuta
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
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13
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van Rees K, Hield EK, Carpentier A, Maron L, Sproules S, Love JB. Exploring the Redox Properties of Bench-Stable Uranyl(VI) Diamido-Dipyrrin Complexes. Inorg Chem 2022; 61:3249-3255. [PMID: 35129967 PMCID: PMC9007458 DOI: 10.1021/acs.inorgchem.1c03744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The
uranyl complexes UO2(OAc)(L) and UO2Cl(L) of the redox-active, acyclic diamido–dipyrrin
anion L– are reported
and their redox properties explored. Because of the inert nature of
the complexes toward hydrolysis and oxidation, synthesis of both the
ligands and complexes was conducted under ambient conditions. Voltammetric,
electron paramagnetic resonance spectroscopy, and density functional
theory studies show that one-electron chemical reduction by the reagent
CoCp2 leads to the formation of a dipyrrin radical for
both complexes [Cp2Co][UO2(OAc)(L•)] and [Cp2Co][UO2Cl(L•)]. Air-stable
uranyl complexes of diamido−dipyrrin ligands
undergo one-electron reduction to form highly air-sensitive ligand
radical complexes instead of uranyl(V) complexes seen for diimine
analogues.
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Affiliation(s)
- Karlotta van Rees
- EaStCHEM School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, U.K
| | - Emma K Hield
- EaStCHEM School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, U.K
| | - Ambre Carpentier
- Laboratoire de Physique et Chimie de Nano-Objets, Institut National des Sciences Appliquées, Université de Toulouse, 135 avenue de Rangueil, 31077 Toulouse Cedex 4, France
| | - Laurent Maron
- Laboratoire de Physique et Chimie de Nano-Objets, Institut National des Sciences Appliquées, Université de Toulouse, 135 avenue de Rangueil, 31077 Toulouse Cedex 4, France
| | - Stephen Sproules
- WestCHEM School of Chemistry, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Jason B Love
- EaStCHEM School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, U.K
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14
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Panchavarnam S, Sengupta R, Ravikanth M. Synthesis, Structure, and Properties of Palladium(II) Complex of α-Formyl Pyrrolyl Dipyrromethene. Dalton Trans 2022; 51:5587-5595. [DOI: 10.1039/d2dt00166g] [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
A simple α-formyl pyrrolyl dipyrromethene ligand was synthesized by deboronation of BF2-complex of α-formyl pyrrolyl dipyrrin under Lewis acid-catalyzed conditions. The α-formyl pyrrolyl dipyrrin ligand was treated with PdCl2 in...
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15
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Wu T, Wang S, Lv Y, Fu T, Jiang J, Lu X, Yu ZP, zhang J, Wang L, Zhou HP. A New Bis(thioether)-Dipyrrin N2S2 Ligand and Its Coordination Behaviors to Nickel, Copper and Zinc. Dalton Trans 2022; 51:9699-9707. [DOI: 10.1039/d2dt01282k] [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
Tetradentate N2S2 coordination platforms are widespread in biological system and have endowed the metalloenzymes and metalloproteins with abundant reactivities and functions. However, there have only three types of N2S2 scaffolds...
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16
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Belen’kii LI, Gazieva GA, Evdokimenkova YB, Soboleva NO. The literature of heterocyclic chemistry, Part XX, 2020. ADVANCES IN HETEROCYCLIC CHEMISTRY 2022. [DOI: 10.1016/bs.aihch.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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Tomat E, Curtis CJ. Biopyrrin Pigments: From Heme Metabolites to Redox-Active Ligands and Luminescent Radicals. Acc Chem Res 2021; 54:4584-4594. [PMID: 34870973 DOI: 10.1021/acs.accounts.1c00613] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox-active ligands in coordination chemistry not only modulate the reactivity of the bound metal center but also serve as electron reservoirs to store redox equivalents. Among many applications in contemporary chemistry, the scope of redox-active ligands in biology is exemplified by the porphyrin radicals in the catalytic cycles of multiple heme enzymes (e.g., cytochrome P450, catalase) and the chlorophyll radicals in photosynthetic systems. This Account reviews the discovery of two redox-active ligands inspired by oligopyrrolic fragments found in biological settings as products of heme metabolism.Linear oligopyrroles, in which pyrrole heterocycles are linked by methylene or methine bridges, are ubiquitous in nature as part of the complex, multistep biosynthesis and degradation of hemes and chlorophylls. Bile pigments, such as biliverdin and bilirubin, are common and well-studied tetrapyrroles with characteristic pyrrolin-2-one rings at both terminal positions. The coordination chemistry of these open-chain pigments is less developed than that of porphyrins and other macrocyclic oligopyrroles; nevertheless, complexes of biliverdin and its synthetic analogs have been reported, along with fluorescent zinc complexes of phytobilins employed as bioanalytical tools. Notably, linear conjugated tetrapyrroles inherit from porphyrins the ability to stabilize unpaired electrons within their π system. The isolated complexes, however, present helical structures and generally limited stability.Smaller biopyrrins, which feature three or two pyrrole rings and the characteristic oxidized termini, have been known for several decades following their initial isolation as urinary pigments and heme metabolites. Although their coordination chemistry has remained largely unexplored, these compounds are structurally similar to the well-established tripyrrin and dipyrrin ligands employed in a broad variety of metal complexes. In this context, our study of the coordination chemistry of tripyrrin-1,14-dione and dipyrrin-1,9-dione was motivated by the potential to retain on these compact, versatile platforms the reversible ligand-based redox chemistry of larger tetrapyrrolic systems.The tripyrrindione ligand coordinates several divalent transition metals (i.e., Pd(II), Ni(II) Cu(II), Zn(II)) to form neutral complexes in which an unpaired electron is delocalized over the conjugated π system. These compounds, which are stable at room temperature and exposed to air, undergo reversible one-electron processes to access different redox states of the ligand system without affecting the oxidation state and coordination geometry of the metal center. We also characterized ligand-based radicals on the dipyrrindione platform in both homoleptic and heteroleptic complexes. In addition, this study documented noncovalent interactions (e.g., interligand hydrogen bonds with the pyrrolinone carbonyls, π-stacking of ligand-centered radicals) as important aspects of this coordination chemistry. Furthermore, the fluorescence of the zinc-bound tripyrrindione radical and the redox-switchable emission of a dipyrrindione BODIPY-type fluorophore showcased the potential interplay of redox chemistry and luminescence in these compounds. Supported by computational analyses, the portfolio of properties revealed by this investigation takes the tripyrrindione and dipyrrindione motifs of heme metabolites to the field of redox-active ligands, where they are positioned to offer new opportunities for catalysis, sensing, supramolecular systems, and functional materials.
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Affiliation(s)
- Elisa Tomat
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0041, United States
| | - Clayton J. Curtis
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0041, United States
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18
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Panchavarnam S, Sengupta R, Ravikanth M. Bis-Palladium Complex of α-Benzimidazole 9-Pyrrolyl Dipyrromethene: Synthesis, Structure, and Spectral and Catalytic Properties. Inorg Chem 2021; 60:15686-15694. [PMID: 34605630 DOI: 10.1021/acs.inorgchem.1c02353] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new ligand is designed and synthesized in two steps starting from α-formyl 3-pyrrolyl BODIPY. In the first step, the α-formyl 3-pyrrolyl BODIPY was condensed with 1,2-diaminobenzene in toluene at reflux and afforded α-benzimidazole 3-pyrrolyl BODIPY in 16% yield. In the second step, α-benzimidazole 3-pyrrolyl BODIPY was decomplexed upon being treated with Lewis acid AlCl3 and afforded the desired ligand α-benzimidazole 9-pyrrolyl dipyrromethene. However, the ligand was not very stable and reacted further with PdCl2 in CH3CN for 1 h at reflux followed by recrystallization and afforded a novel bis-palladium complex of α-benzimidazole 9-pyrrolyl dipyrromethene in 36% yield. The bis-palladium complex was characterized and studied by high-resolution mass spectrometry, one- and two-dimensional nuclear magnetic resonance, X-ray crystallography, absorption, and density functional theory/time-dependent DFT (DFT/TD-DFT) studies. The X-ray structure revealed that two ligands and two Pd(II) ions were involved in forming a unique complex in which each Pd(II) ion was coordinated to three pyrrole N atoms of the first ligand and the benzimidazole N atom of the second ligand in a distorted square planar geometry. The absorption spectrum of the bis-palladium complex shows ill-defined, broad, and less intense bands in the region of 345-425 nm along with split bands in the higher-wavelength region of 600-630 nm. The bis-palladium complex was nonfluorescent, and the results of DFT/TD-DFT studies were in agreement with the experimental observations. The preliminary studies indicated that the bis-palladium complex can act as an efficient catalyst for coupling different aryl bromides with phenylboronic acid.
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Affiliation(s)
| | - Rima Sengupta
- Indian Institute of Technology, Powai, Mumbai 400076, India
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19
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Nguyen THT, Eerdun C, Okayama T, Hisanaga S, Tominaga T, Mochida T, Setsune JI. Stereochemistry and chiroptical properties of bimetallic single helicates of hexapyrrole-α, ω-dicarbaldimines with high diastereoselectivity. J PORPHYR PHTHALOCYA 2021. [DOI: 10.1142/s108842462150111x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bimetallic complexes of hexapyrrole-[Formula: see text],[Formula: see text]-dicarbaldimines consisting of a pair of four-coordinate metal sites adopt a helical closed [Formula: see text]-symmetric form or sigmoidal open forms depending on whether the 2,2[Formula: see text]-bipyrrole subunit at the center of the hexapyrrole chain takes cis- or trans-conformation. X-ray crystallography of a bisNi complex having N-[([Formula: see text]-1-cyclohexylethyl]carbaldimine units at both ends of the hexapyrrole chain revealed a non-symmetric heterohelical open form where the metal coordination sites of opposite helical sense sit on opposite sides of the central 2,2[Formula: see text]-bipyrrole subunit. BisPd complexes preferred a closed [Formula: see text] form and a steric bulk at the 3,3[Formula: see text]-position of the 2,2[Formula: see text]-bipyrrole subunit improved the helical sense bias. A bisPd complex with N-[([Formula: see text]-1-cyclohexylethyl]carbaldimine units adopts a helical closed [Formula: see text] form exclusively with full bias for a [Formula: see text]-helical sense. These bimetallic single stranded helicates were reversibly oxidized to [Formula: see text]-cation radicals at 0.1[Formula: see text]0.3 V vs. a ferrocene/ferrocenium couple and spectroelectrochemistry revealed remarkable absorption and CD spectral changes in the Vis-NIR region.
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Affiliation(s)
- Thi Hien Thuy Nguyen
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Chaolu Eerdun
- School of Pharmaceutical Science, Inner Mongolia Medical University Jinshan Econimic & Technology Development District, Hohhot 010100, China
| | - Takuya Okayama
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Satoshi Hisanaga
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Takumi Tominaga
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Tomoyuki Mochida
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Jun-ichiro Setsune
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
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20
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Shin JY, Nguyen AQ. Exquisite chemistries of meso-pentafluorophenyl and meso-(2,6-dichlorophenyl) dipyrromethanes. J PORPHYR PHTHALOCYA 2021. [DOI: 10.1142/s1088424621300019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
meso-Aryl dipyrromethanes are important building blocks to create various practical molecules, and the electron-withdrawing effect of the meso-aryls can play an important role in improving/controlling their reactivities in further reactions: meso-Pentafluorophenyl and meso-(2,6-dichlorophenyl) substituted dipyrromethanes towards the associating dipyrrins and other derivatives have been investigated, in which coordination with different transition metals followed by the dissociation of the metal coordination by interruption of proton and halide ions have been verified. Furthermore, simple DDQ-oxidations of the dipyrromethanes have afforded DDQ-dipyrrin adducts which were delivered to distinctly advanced molecular rearrangements in the presence of acid and base. Vinylene bisdipyrrin compounds, obtained in the reactions of DDQ-dipyrrin adducts with a Lewis base triethylamine, have produced expanded porphyrinoid bis-nickel complexes during the metalation procedure with nickel acetate, while a cobalt metalation of the vinylene bisdipyrrin compounds resulted in an isolation of diamagnetic octahedral cobalt(III) complex. Moreover, meso-pentafluorophenyl and meso-(2,6-dichlorophenyl) dipyrromethanes have been useful platforms to accomplish size-controlled series of meso-aryl-substituted expanded porphyrins and easy separation/purification of selective meso-aryl expanded porphyrins, in which advanced metal complexes and various fascinating properties and reactivities admitting moderate functional molecules have arisen.
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Affiliation(s)
- Ji-Young Shin
- Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - An Quang Nguyen
- Department of Chemistry, School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
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21
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Hohlfeld BF, Gitter B, Kingsbury CJ, Flanagan KJ, Steen D, Wieland GD, Kulak N, Senge MO, Wiehe A. Dipyrrinato-Iridium(III) Complexes for Application in Photodynamic Therapy and Antimicrobial Photodynamic Inactivation. Chemistry 2021; 27:6440-6459. [PMID: 33236800 PMCID: PMC8248005 DOI: 10.1002/chem.202004776] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/24/2020] [Indexed: 12/24/2022]
Abstract
The generation of bio-targetable photosensitizers is of utmost importance to the emerging field of photodynamic therapy and antimicrobial (photo-)therapy. A synthetic strategy is presented in which chelating dipyrrin moieties are used to enhance the known photoactivity of iridium(III) metal complexes. Formed complexes can thus be functionalized in a facile manner with a range of targeting groups at their chemically active reaction sites. Dipyrrins with N- and O-substituents afforded (dipy)iridium(III) complexes via complexation with the respective Cp*-iridium(III) and ppy-iridium(III) precursors (dipy=dipyrrinato, Cp*=pentamethyl-η5 -cyclopentadienyl, ppy=2-phenylpyridyl). Similarly, electron-deficient [IrIII (dipy)(ppy)2 ] complexes could be used for post-functionalization, forming alkenyl, alkynyl and glyco-appended iridium(III) complexes. The phototoxic activity of these complexes has been assessed in cellular and bacterial assays with and without light; the [IrIII (Cl)(Cp*)(dipy)] complexes and the glyco-substituted iridium(III) complexes showing particular promise as photomedicine candidates. Representative crystal structures of the complexes are also presented.
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Affiliation(s)
- Benjamin F. Hohlfeld
- Institut für Chemie u. BiochemieFreie Universität BerlinTakustr. 314195BerlinGermany
- biolitec research GmbHOtto-Schott-Str. 1507745JenaGermany
| | | | - Christopher J. Kingsbury
- Medicinal Chemistry, Trinity Translational Medicine InstituteTrinity Centre for Health SciencesTrinity College Dublin, The University of DublinSt James's HospitalDublin8Ireland
| | - Keith J. Flanagan
- Medicinal Chemistry, Trinity Translational Medicine InstituteTrinity Centre for Health SciencesTrinity College Dublin, The University of DublinSt James's HospitalDublin8Ireland
| | - Dorika Steen
- biolitec research GmbHOtto-Schott-Str. 1507745JenaGermany
| | | | - Nora Kulak
- Institut für Chemie u. BiochemieFreie Universität BerlinTakustr. 314195BerlinGermany
- Institut für ChemieOtto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106MagdeburgGermany
| | - Mathias O. Senge
- Medicinal Chemistry, Trinity Translational Medicine InstituteTrinity Centre for Health SciencesTrinity College Dublin, The University of DublinSt James's HospitalDublin8Ireland
- Institute for Advanced Study (TUM-IAS)Technical University of MunichLichtenbergstrasse 2a85748GarchingGermany
| | - Arno Wiehe
- Institut für Chemie u. BiochemieFreie Universität BerlinTakustr. 314195BerlinGermany
- biolitec research GmbHOtto-Schott-Str. 1507745JenaGermany
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22
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van Rees K, Love JB. Synthesis and complexes of a constrained-cavity Schiff-base dipyrrin macrocycle. Dalton Trans 2021; 50:1610-1613. [PMID: 33508062 DOI: 10.1039/d1dt00175b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new constrained-cavity [1 + 1] Schiff-base dipyrrin macrocycle comprising an N4 donor-pocket has been synthesised by spontaneous oxidation and in situ crystallisation. Access to Fe(ii) and Zn(ii) complexes is achieved by salt elimination reactions of the lithium salt. All compounds have been characterised by NMR and UV-vis spectroscopy, X-ray crystallography, and DFT analysis.
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Affiliation(s)
- Karlotta van Rees
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, The King's Buildings, Edinburgh, EH9 3FJ, UK.
| | - Jason B Love
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, The King's Buildings, Edinburgh, EH9 3FJ, UK.
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23
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Shin JY. The synthesis and characterization of the octahedral Co III complex of a pyrrolopyrrolizine derivative formed with dicyanovinylene-bis-( meso-aryl)dipyrrin. RSC Adv 2021; 11:2315-2319. [PMID: 35424195 PMCID: PMC8693670 DOI: 10.1039/d0ra09452h] [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: 11/06/2020] [Accepted: 12/15/2020] [Indexed: 01/05/2023] Open
Abstract
A low spin state and diamagnetic CoIII complex 1 possessing pyrrolopyrrolizine ligands formed with dicyanovinylene-bis-(meso-aryl)dipyrrin was synthesized via the thermally activated metalation with CoCl2 and isolated via column chromatography. The nuclear magnetic resonance of complex 1 revealed diamagnetism, thereby confirming the structure of the octahedral CoIII-complex of strong-field ligands. The resulting molecular structure of 1 was elucidated by the X-ray diffraction analysis. An arrangement of two pyrrolizine-ligands for the metal chelation was found in the AB-BA order, which was distinct from the case observed during the formation of bis-NiII-expanded porphyrinoids.
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Affiliation(s)
- Ji-Young Shin
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University Furo-cho, Chikusa-ku Nagoya 464-8603 Japan +81-52-747-6771
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24
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Fang Y, Osterloh WR, Desbois N, Pacquelet S, Fleurat-Lessard P, Gros CP, Kadish KM. Solvent and Anion Effects on the Electrochemistry of Manganese Dipyrrin-Bisphenols. Inorg Chem 2020; 59:15913-15927. [PMID: 33064946 DOI: 10.1021/acs.inorgchem.0c02416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of "N2O2-type" manganese dipyrrin-bisphenols (DPP), formulated as (Ar)DPPMn, where Ar = pentafluorophenyl (F5Ph), phenyl (Ph), or mesityl (Mes), were electrochemically and spectroscopically characterized in nonaqueous media with and without added anions in the form of tetrabutylammonium salts (TBAX where X = ClO4-, PF6-, BF4-, F-, Cl-, OH-, or CN-). Two major one-electron reductions are observed under most solution conditions, the first of which is assigned as a MnIII/II process and the second as electron addition to the π-ring system as confirmed by spectroelectrochemistry. Each MnIII complex also exhibits one or two one-electron oxidations, the exact number depending upon the positive potential limit of the electrochemical solvent. The two oxidations are separated by 580-590 mV in CH3CN containing 0.1 M TBAPF6 and are assigned as π-ring-centered electron transfers to stepwise form a (Ar)DPPMnIII π-cation radical and dication under these solution conditions. Comparisons are made between redox properties of (Ar)DPPMn and manganese(III) porphyrins, corroles, and corrolazines each of which contains an innocent trianionic complexing ligand. The redox behavior and spectroscopic properties of [(Ar)DPPMn]n where n = 0, -1, or +1 are also compared to that of other structurally related [(Ar)DPPM]n complexes under similar solution conditions where M = CoII, CuII, BIII, or AuIII.
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Affiliation(s)
- Yuanyuan Fang
- School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.,Department of Chemistry, University of Houston, Houston, Texas 77204-5003 United States
| | - W Ryan Osterloh
- Department of Chemistry, University of Houston, Houston, Texas 77204-5003 United States
| | - Nicolas Desbois
- ICMUB, UMR CNRS 6302, Université Bourgogne Franche-Comté, 21000 Dijon, France
| | - Sandrine Pacquelet
- ICMUB, UMR CNRS 6302, Université Bourgogne Franche-Comté, 21000 Dijon, France
| | | | - Claude P Gros
- ICMUB, UMR CNRS 6302, Université Bourgogne Franche-Comté, 21000 Dijon, France
| | - Karl M Kadish
- Department of Chemistry, University of Houston, Houston, Texas 77204-5003 United States
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25
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Smith CD, Thompson A. Facile deprotection of F-BODIPYs using methylboronic acid. RSC Adv 2020; 10:24273-24279. [PMID: 35516207 PMCID: PMC9055154 DOI: 10.1039/d0ra05151a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 06/12/2020] [Indexed: 11/21/2022] Open
Abstract
4,4-Difluoro-4-bora-3a,4a-diaza-s-indacenes (F-BODIPYs) are deprotected through removal of the -BF2 moiety upon treatment with methylboronic acid. The tolerance of various substitution patterns about the dipyrrinato core is demonstrated via the deprotection of thirteen F-BODIPYs and an F-aza-BODIPY. Work-up with aq. HBr affords the desired dipyrin HBr salt in quantitative yield without need for purification.
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Affiliation(s)
- Craig D Smith
- Department of Chemistry, Dalhousie University PO BOX 15000 Halifax NS B3H 4R2 Canada
| | - Alison Thompson
- Department of Chemistry, Dalhousie University PO BOX 15000 Halifax NS B3H 4R2 Canada
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