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Shephard ACG, Delon A, Chevreux S, Martinez A, Guo Z, Deacon GB, Lemercier G, McClenaghan N, Jonusauskas G, Junk PC, Jaroschik F. Divalent ansa-Octaphenyllanthanocenes: Synthesis, Structures, and Eu II Luminescence. Inorg Chem 2024; 63:9395-9405. [PMID: 37310150 DOI: 10.1021/acs.inorgchem.3c01062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Reductive dimerization of fulvenes using low-valent metal precursors is a straightforward one-step approach to access ethylene-bridged metallocenes. This process has so far mainly been employed with fulvenes carrying one or two substituents in the exocyclic position. In this work, a new synthesis of the unsubstituted exocyclic 1,2,3,4-tetraphenylfulvene (1), its full structural characterization by NMR spectroscopy and single-crystal X-ray diffraction, as well as some photophysical properties and its first use in reductive dimerization are described. This fulvene reacted with different lanthanoid metals in thf to provide the divalent ansa-octaphenylmetallocenes [Ln(C5Ph4CH2)2(thf)n] (Ln = Sm, n = 2 (2); Ln = Eu, n = 2 (3); and Ln = Yb, n = 1 (4)). These complexes were characterized by X-ray diffraction, laser desorption/ionization time of flight mass spectrometry, and, in the case of Sm and Yb, multinuclear NMR spectroscopy, showing the influence of the ansa-bridge on solution and solid-state structures compared to previously reported unbridged metallocenes. Furthermore, the luminescence properties of the Eu ansa complex 3 were studied in solution and the solid state, revealing significant differences with the known octa- and deca-phenyleuropocenes, [Eu(C5Ph4H)2(dme)] and [Eu(C5Ph5)2].
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Affiliation(s)
- Angus C G Shephard
- College of Science and Engineering, James Cook University, Townsville 4811, Australia
| | - Aymeric Delon
- College of Science and Engineering, James Cook University, Townsville 4811, Australia
- Université de Reims Champagne-Ardenne, ICMR, UMR 7312, Reims 56187, France
| | - Sylviane Chevreux
- Université de Reims Champagne-Ardenne, ICMR, UMR 7312, Reims 56187, France
| | - Agathe Martinez
- Université de Reims Champagne-Ardenne, ICMR, UMR 7312, Reims 56187, France
| | - Zhifang Guo
- College of Science and Engineering, James Cook University, Townsville 4811, Australia
| | - Glen B Deacon
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Gilles Lemercier
- Université de Reims Champagne-Ardenne, ICMR, UMR 7312, Reims 56187, France
| | - Nathan McClenaghan
- Université Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, Talence F-33400, France
| | | | - Peter C Junk
- College of Science and Engineering, James Cook University, Townsville 4811, Australia
| | - Florian Jaroschik
- ICGM, Université Montpellier, CNRS, ENSCM, Montpellier 34090, France
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2
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Bokouende SS, Kulasekara DN, Worku SA, Ward CL, Kajjam AB, Lutter JC, Allen MJ. Expanding the Coordination of f-Block Metals with Tris[2-(2-methoxyethoxy)ethyl]amine: From Molecular Complexes to Cage-like Structures. Inorg Chem 2024; 63:9434-9450. [PMID: 38016147 PMCID: PMC11129929 DOI: 10.1021/acs.inorgchem.3c02752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
Low-valent f-block metals have intrinsic luminescence, electrochemical, and magnetic properties that are modulated with ligands, causing the coordination chemistry of these metals to be imperative to generating critical insights needed to impact modern applications. To this end, we synthesized and characterized a series of twenty-seven complexes of f-metal ions including EuII, YbII, SmII, and UIII and hexanuclear clusters of LaIII and CeIII to study the impact of tris[2-(2-methoxyethoxy)ethyl]amine, a flexible acyclic analogue of the extensively studied 2.2.2-cryptand, on the coordination chemistry and photophysical properties of low-valent f-block metals. We demonstrate that the flexibility of the ligand enables luminescence tunability over a greater range than analogous cryptates of EuII in solution. Furthermore, the ligand also displays a variety of binding modes to f-block metals in the solid state that are inaccessible to cryptates of low-valent f-block metals. In addition to serving as a ligand for f-block metals of various sizes and oxidation states, tris[2-(2-methoxyethoxy)ethyl]amine also deprotonates water molecules coordinated to trivalent triflate salts of f-block metal ions, enabling the isolation of hexanuclear clusters containing either LaIII or CeIII. The ligand was also found to bind more tightly to YbII and UIII in the solid state compared to 2.2.2-cryptand, suggesting that it can play a role in the isolation of other low-valent f-block metals such CfII, NpIII, and PuIII. We expect that our findings will inspire applications of tris[2-(2-methoxyethoxy)ethyl]amine in the design of light-emitting diodes and the synthesis of extremely reducing divalent f-block metal complexes that are of interest for a wide range of applications.
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Affiliation(s)
- Sergely Steephen Bokouende
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - D Nuwangi Kulasekara
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Sara A Worku
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Cassandra L Ward
- Lumigen Instrument Center, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Aravind B Kajjam
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Jacob C Lutter
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Matthew J Allen
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
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3
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Hilpmann S, Moll H, Drobot B, Vogel M, Hübner R, Stumpf T, Cherkouk A. Europium(III) as luminescence probe for interactions of a sulfate-reducing microorganism with potentially toxic metals. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 264:115474. [PMID: 37716067 DOI: 10.1016/j.ecoenv.2023.115474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/07/2023] [Accepted: 09/11/2023] [Indexed: 09/18/2023]
Abstract
Microorganisms show a high affinity for trivalent actinides and lanthanides, which play an important role in the safe disposal of high-level radioactive waste as well as in the mining of various rare earth elements. The interaction of the lanthanide Eu(III) with the sulfate-reducing microorganism Desulfosporosinus hippei DSM 8344T, a representative of the genus Desulfosporosinus that naturally occurs in clay rock and bentonite, was investigated. Eu(III) is often used as a non-radioactive analogue for the trivalent actinides Pu(III), Am(III), and Cm(III), which contribute to a major part of the radiotoxicity of the nuclear waste. D. hippei DSM 8344T showed a weak interaction with Eu(III), most likely due to a complexation with lactate in artificial Opalinus Clay pore water. Hence, a low removal of the lanthanide from the supernatant was observed. Scanning transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy revealed a bioprecipitation of Eu(III) with phosphates potentially excreted from the cells. This demonstrates that the ongoing interaction mechanisms are more complex than a simple biosorption process. The bioprecipitation was also verified by luminescence spectroscopy, which showed that the formation of the Eu(III) phosphate compounds starts almost immediately after the addition of the cells. Moreover, chemical microscopy provided information on the local distribution of the different Eu(III) species in the formed cell aggregates. These results provide first insights into the interaction mechanisms of Eu(III) with sulfate-reducing bacteria and contribute to a comprehensive safety concept for a high-level radioactive waste repository, as well as to a better understanding of the fate of heavy metals (especially rare earth elements) in the environment.
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Affiliation(s)
- Stephan Hilpmann
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Henry Moll
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Björn Drobot
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Manja Vogel
- VKTA - Strahlenschutz, Analytik & Entsorgung Rossendorf e. V., Dresden, Germany
| | - René Hübner
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Dresden, Germany
| | - Thorsten Stumpf
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Andrea Cherkouk
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany.
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4
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Klementyeva SV, Woern K, Schrenk C, Zhang M, Khusniyarov MM, Schnepf A. [(thf) 5Ln(Ge 9{Si(SiMe 3) 3} 2)] (Ln = Eu, Sm, Yb): Capping Metalloid Germanium Cluster with Lanthanides. Inorg Chem 2023; 62:5614-5621. [PMID: 36967670 DOI: 10.1021/acs.inorgchem.3c00165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
We report the synthesis of three neutral complexes with different coordination modes of a di-silylated metalloid germanium cluster to divalent lanthanides [(thf)5Ln(ηn-Ge9(Hyp)2)] (Ln = Yb (1, n = 1); Eu (2, n = 2, 3), Sm (3, n = 2, 3); Hyp = Si(SiMe3)3) by the salt metathesis of LnI2 with K2[Ge9(Hyp)2] in THF. The complexes were characterized by elemental analysis, nuclear magnetic resonance and UV-vis-NIR spectroscopy, and single-crystal X-ray diffraction. In thf solution, the formation of contact or solvate-separated ion pairs depending on the concentration is assumed. Compound 2 exhibits a blue luminescence typical for Eu2+. The solid-state magnetic measurements of compounds 2 and 3 confirm the presence of divalent europium and samarium, respectively.
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Barraza R, Sertage AG, Kajjam AB, Ward CL, Lutter JC, Schlegel HB, Allen MJ. Properties of Amine-Containing Ligands That Are Necessary for Visible-Light-Promoted Catalysis with Divalent Europium. Inorg Chem 2022; 61:19649-19657. [PMID: 36417708 PMCID: PMC9771976 DOI: 10.1021/acs.inorgchem.2c02911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We describe a study of the influence of amine-containing ligands on the photoredox-relevant properties of EuII toward the rational design of EuII-containing catalysts for visible-light-promoted photoredox reactions. We report our observations of the effects of the degree of functionalization of amines, denticity, and macrocylic ligands on the absorbance of EuII. Ligands that contain secondary amines bathochromically shift the absorbance of EuCl2 relative to ligands that contain primary or tertiary amines. Similarly, ligands of larger denticity have a larger bathochromic shift of the absorbance than ligands of smaller denticity. We observed that macrocyclic ligands have a larger effect on the absorbance of EuCl2 than nonmacrocyclic ligands. Also, we report the photoredox reactivity of four new EuII-containing complexes. These observations are potentially influential in understanding the ligand properties that promote the use of EuII in visible-light-promoted photoredox catalysis.
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Affiliation(s)
- Ramiro Barraza
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, United States
| | - Alexander G. Sertage
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, United States
| | - Aravind B. Kajjam
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, United States
| | - Cassandra L. Ward
- Lumigen Instrument Center, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, United States
| | - Jacob C. Lutter
- Department of Chemistry and Biochemistry, University of Southern Indiana, 8600 University Blvd, Evansville, IN 47712, United States
| | - H. Bernhard Schlegel
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, United States
| | - Matthew J. Allen
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, United States,Corresponding Author
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6
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Bokouende SS, Jenks TC, Ward CL, Allen MJ. Solid-state and solution-phase characterization of Sm II-aza[2.2.2]cryptate and its methylated analogue. Dalton Trans 2022; 51:10852-10855. [PMID: 35781473 PMCID: PMC9650674 DOI: 10.1039/d2dt01823c] [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
Two new SmII-azacryptates are reported that differ in steric hindrance and Lewis basicity of donor atoms. The sterically hindered complex has a smaller coordination number and a more negative electrochemical potential than the complex with less steric hindrance.
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Affiliation(s)
| | - Tyler C Jenks
- Deparptment of Chemistry, Wayne State University, 5101 Cass Ave., Detroit, MI 48202, USA.
| | - Cassandra L Ward
- Lumigen Instrument Center, Wayne State University, 5101 Cass Ave., Detroit, MI 48202, USA
| | - Matthew J Allen
- Deparptment of Chemistry, Wayne State University, 5101 Cass Ave., Detroit, MI 48202, USA.
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7
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Acharjya A, Corbin BA, Prasad E, Allen MJ, Maity S. Solvation-Controlled Emission of Divalent Europium Salts. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.113892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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8
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Yan W, Li T, Cai Z, Qi H, Guo R, Huo P, Liu Z, Bian Z. Systematic tuning of the emission colors and redox potential of Eu( ii)-containing cryptates by changing the N/O ratio of cryptands. Inorg Chem Front 2022. [DOI: 10.1039/d2qi01216b] [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
The λmax, excited-state lifetimes, and the anodic peak potential of Eu2+/Eu3+ for Eu(ii)-containing cryptates depend linearly on the number of N atoms.
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Affiliation(s)
- Wenchao Yan
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Tingzhou Li
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zelun Cai
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Hao Qi
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Ruoyao Guo
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Peihao Huo
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zhiwei Liu
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zuqiang Bian
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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9
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Prieto A, Jaroschik F. Recent Applications of Rare Earth Complexes in Photoredox Catalysis for Organic
Synthesis. CURR ORG CHEM 2022. [DOI: 10.2174/1385272825666211126123928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
:
In recent years, photoredox catalysis has appeared as a new paradigm for forging a
wide range of chemical bonds under mild conditions using abundant reagents. This approach
allows many organic transformations through the generation of various radical species, enabling
the valorization of non-traditional partners. A continuing interest has been devoted to
the discovery of novel radical-generating procedures. Over the last ten years, strategies using
rare-earth complexes as either redox-active centers or as redox-neutral Lewis acids have
emerged. This review provides an overview of the recent accomplishments made in this field.
It especially aims to demonstrate the utility of rare-earth complexes for ensuring photocatalytic
transformations and to inspire future developments.
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Affiliation(s)
- Alexis Prieto
- ICGM, Univ Montpellier, CNRS, ENSCM, Montpellier, France
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10
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Galimov DI, Yakupova SM, Vasilyuk KS, Bulgakov RG. A novel gas assay for ultra-small amounts of molecular oxygen based on the chemiluminescence of divalent europium. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113430] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Poe TN, Beltrán-Leiva MJ, Celis-Barros C, Nelson WL, Sperling JM, Baumbach RE, Ramanantoanina H, Speldrich M, Albrecht-Schönzart TE. Understanding the Stabilization and Tunability of Divalent Europium 2.2.2B Cryptates. Inorg Chem 2021; 60:7815-7826. [PMID: 33990139 DOI: 10.1021/acs.inorgchem.1c00300] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Lanthanides such as europium with more accessible divalent states are useful for studying redox stability afforded by macrocyclic organic ligands. Substituted cryptands, such as 2.2.2B cryptand, that increase the oxidative stability of divalent europium also provide coordination environments that support synthetic alterations of Eu(II) cryptate complexes. Two single crystal structures were obtained containing nine-coordinate Eu(II) 2.2.2B cryptate complexes that differ by a single coordination site, the occupation of which is dictated by changes in reaction conditions. A crystal structure containing a [Eu(2.2.2B)Cl]+ complex is obtained from a methanol-THF solvent mixture, while a methanol-acetonitrile solvent mixture affords a [Eu(2.2.2B)(CH3OH)]2+ complex. While both crystals exhibit the typical blue emission observed in most Eu(II) containing compounds as a result of 4f65d1 to 4f7 transitions, computational results show that the substitution of a Cl- anion in the place of a methanol molecule causes mixing of the 5d excited states in the Eu(II) 2.2.2B cryptate complex. Additionally, magnetism studies reveal the identity of the capping ligand in the Eu(II) 2.2.2B cryptate complex may also lead to exchange between Eu(II) metal centers facilitated by π-stacking interactions within the structure, slightly altering the anticipated magnetic moment. The synthetic control present in these systems makes them interesting candidates for studying less stable divalent lanthanides and the effects of precise modifications of the electronic structures of low valent lanthanide elements.
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Affiliation(s)
- Todd N Poe
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee 32306, Florida, United States
| | - Maria J Beltrán-Leiva
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee 32306, Florida, United States
| | - Cristian Celis-Barros
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee 32306, Florida, United States
| | - William L Nelson
- National High Magnetic Field Laboratory, 1800 E. Paul Dirac Drive, Tallahassee, Florida 32310, United States
| | - Joseph M Sperling
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee 32306, Florida, United States
| | - Ryan E Baumbach
- National High Magnetic Field Laboratory, 1800 E. Paul Dirac Drive, Tallahassee, Florida 32310, United States
| | - Harry Ramanantoanina
- Department of Chemistry, Johannes Gutenberg-University of Mainz, Staudingerweg 18, 55128 Mainz, Germany
| | - Manfred Speldrich
- Institut für Anorganische Chemie, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Thomas E Albrecht-Schönzart
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee 32306, Florida, United States.,National High Magnetic Field Laboratory, 1800 E. Paul Dirac Drive, Tallahassee, Florida 32310, United States
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Bailey MD, Jin GX, Carniato F, Botta M, Allen MJ. Rational Design of High-Relaxivity Eu II -Based Contrast Agents for Magnetic Resonance Imaging of Low-Oxygen Environments. Chemistry 2021; 27:3114-3118. [PMID: 33226696 PMCID: PMC7902434 DOI: 10.1002/chem.202004450] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 11/21/2020] [Indexed: 01/01/2023]
Abstract
Metal-based contrast agents for magnetic resonance imaging present a promising avenue to image hypoxia. EuII -based contrast agents have a unique biologically relevant redox couple, EuII/III , that distinguishes this metal for use in hypoxia imaging. To that end, we investigated a strategy to enhance the contrast-enhancing capabilities of EuII -based cryptates in magnetic resonance imaging by controlling the rotational dynamics. Two dimetallic, EuII -containing cryptates were synthesized to test the efficacy of rigid versus flexible coupling strategies. A flexible strategy to dimerization led to a modest (114 %) increase in contrast enhancement per Eu ion (60 MHz, 298 K), but a rigid linking strategy led to an excellent (186 %) increase in contrast enhancement despite this compound's having the smaller molecular mass of the two dimetallic complexes. We envision the rigid linking strategy to be useful in the future design of potent EuII -based contrast agents for magnetic resonance imaging.
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Affiliation(s)
- Matthew D Bailey
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
| | - Guo-Xia Jin
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for, Chemical Imaging, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Normal University, Jinan, 250014, P. R. China
| | - Fabio Carniato
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "Amedeo Avogadro", Viale T. Michel 11, 15121, Alessandria, Italy
| | - Mauro Botta
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "Amedeo Avogadro", Viale T. Michel 11, 15121, Alessandria, Italy
| | - Matthew J Allen
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI, 48202, USA
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13
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Barraza R, Allen MJ. Lanthanide Luminescence in Visible-Light-Promoted Photochemical Reactions. Molecules 2020; 25:molecules25173892. [PMID: 32858962 PMCID: PMC7503482 DOI: 10.3390/molecules25173892] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 11/17/2022] Open
Abstract
The excitation of lanthanides with visible light to promote photochemical reactions has garnered interest in recent years. Lanthanides serve as initiators for photochemical reactions because they exhibit visible-light-promoted 4f→5d transitions that lead to emissive states with electrochemical potentials that are more negative than the corresponding ground states. The lanthanides that have shown the most promising characteristics for visible-light promoted photoredox are SmII, EuII, and CeIII. By understanding the effects that ligands have on the 5d orbitals of SmII, EuII, and CeIII, luminescence and reactivity can be rationally modulated using coordination chemistry. This review briefly overviews the photochemical reactivity of SmII, EuII, and CeIII with visible light; the properties that influence the reactivity of these ions; and the research that has been reported towards modulating their photochemical-relevant properties using visible light and coordination chemistry.
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