1
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Bouda M, Bertke JA, Wolf C. Organocatalytic Asymmetric Conjugate Addition of Fluorooxindoles to Quinone Methides. J Org Chem 2024; 89:6100-6105. [PMID: 38619814 PMCID: PMC11077483 DOI: 10.1021/acs.joc.4c00062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/24/2024] [Accepted: 04/03/2024] [Indexed: 04/16/2024]
Abstract
Fluorooxindoles undergo asymmetric Michael addition to para-quinone methides under phase-transfer conditions with 10 mol% of a readily available cinchona alkaloid ammonium catalyst. This reaction affords sterically encumbered, multifunctional fluorinated organic compounds displaying two adjacent chirality centers with high yields, ee's and dr's.
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Affiliation(s)
- Maria Bouda
- Chemistry Department, Georgetown University, Washington, D.C. 20057, United States
| | - Jeffery A. Bertke
- Chemistry Department, Georgetown University, Washington, D.C. 20057, United States
| | - Christian Wolf
- Chemistry Department, Georgetown University, Washington, D.C. 20057, United States
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2
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Nelson E, Bertke JA, Thanzeel FY, Wolf C. Organometallic Chirality Sensing via "Click"-Like η 6-Arene Coordination with an Achiral Cp*Ru(II) Piano Stool Complex. Angew Chem Int Ed Engl 2024:e202404594. [PMID: 38634562 DOI: 10.1002/anie.202404594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/09/2024] [Accepted: 04/18/2024] [Indexed: 04/19/2024]
Abstract
Piano stool complexes have been studied over many years and found widespread applications in organic synthesis, catalysis, materials and drug development. We now report the first examples of quantitative chiroptical molecular recognition of chiral compounds through click-like η6-arene coordination with readily available half sandwich complexes. This conceptually new approach to chirality sensing is based on irreversible acetonitrile displacement of [Cp*Ru(CH3CN)3]PF6 by an aromatic target molecule, a process that is fast and complete within a few minutes at room temperature. The metal coordination coincides with characteristic circular dichroism inductions that can be easily correlated to the absolute configuration and enantiomeric ratio of the bound molecule. A relay assay that decouples the determination of the enantiomeric composition and of the total sample amount by a practical CD/UV measurement protocol was developed and successfully tested. The introduction of piano stool complexes to the chiroptical sensing realm is mechanistically unique and extends the scope of currently known methods with small-molecule probes that require the presence of amino, alcohol, carboxylate or other privileged functional groups for binding of the target compound. A broad application range including pharmaceutically relevant multifunctional molecules and the use in chromatography-free asymmetric reaction analysis are also demonstrated.
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Affiliation(s)
- Eryn Nelson
- Chemistry Department, Georgetown University, 3700 O St NW, Washington, DC-20057
| | - Jeffery A Bertke
- Chemistry Department, Georgetown University, 3700 O St NW, Washington, DC-20057
| | - F Yushra Thanzeel
- Chemistry Department, Georgetown University, 3700 O St NW, Washington, DC-20057
| | - Christian Wolf
- Chemistry Department, Georgetown University, 3700 O St NW, Washington, DC-20057
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3
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Knoell T, Polanco J, MacMillan SN, Bertke JA, Foroutan-Nejad C, Lancaster KM, 'Gus' Bakhoda A. Alkaline earth metal-assisted dinitrogen activation at nickel. Dalton Trans 2024; 53:4689-4697. [PMID: 38362644 PMCID: PMC10922974 DOI: 10.1039/d3dt03984f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Rare examples of trinuclear [Ni-N2-M-N2-Ni] core (M = Ca, Mg) with linear bridged dinitrogen ligands are reported in this work. The reduction of [iPr2NN]Ni(μ-Br)2Li(thf)2 (1) (iPr2NN = 2,4-bis-(2,6-diisopropylphenylimido)pentyl) with elemental Mg or Ca in THF under an atmosphere of dinitrogen yields the complex {iPr2NNNi(μ-N2)}2M (thf)4 (M = Mg, complex 2 and M = Ca, complex 3). The bridging end-on (μ-N2)2M(thf)4 moiety connects the two [iPr2NNNi]- nickelate fragments. A combination of X-ray crystallography, solution and solid-state spectroscopy have been applied to characterize complexes 2 and 3, and DFT studies have been used to help explain the bonding and electronic structure in these unique Ni-N2-Mg and Ni-N2-Ca complexes.
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Affiliation(s)
- Theresa Knoell
- Department of Chemistry Towson University, 8000 York Road, Towson, MD 21252, USA.
| | - Jocelyn Polanco
- Department of Chemistry Towson University, 8000 York Road, Towson, MD 21252, USA.
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Jeffery A Bertke
- Georgetown University, Department of Chemistry, Washington, DC 20057, USA
| | - Cina Foroutan-Nejad
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
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4
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Lucas Kane D, Figula BC, Balaraman K, Bertke JA, Wolf C. General alkyl fluoride functionalization via short-lived carbocation-organozincate ion pairs. Nat Commun 2024; 15:1866. [PMID: 38424080 PMCID: PMC10904780 DOI: 10.1038/s41467-024-45756-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 02/05/2024] [Indexed: 03/02/2024] Open
Abstract
Fluorinated organic compounds are frequently used across the chemical and life sciences. Although a large, structurally diverse pool of alkyl fluorides is nowadays available, synthetic applications trail behind the widely accepted utility of other halides. We envisioned that C(sp2)-C(sp3) cross-coupling reactions of alkyl fluorides with fluorophilic organozinc compounds should be possible through a heterolytic mechanism that involves short-lived ion pairs and uses the stability of the Zn-F bond as the thermodynamic driving force. This would be mechanistically different from previously reported radical reactions and overcome long-standing limitations of organometallic cross-coupling methodology, including competing β-hydride elimination, homodimerization and hydrodefluorination. Here, we show a practical Csp3-F bond functionalization method that expands the currently restricted synthetic space of unactivated primary, secondary and tertiary C(sp3)-F bonds but also uses benzylic, propargylic and acyl fluorides. Many functional groups and sterically demanding substrates are tolerated, which allows practical carbon-carbon bond formation and late-stage functionalization.
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Affiliation(s)
- D Lucas Kane
- Georgetown University, Chemistry Department, Washington, DC, 20057, USA
| | - Bryan C Figula
- Georgetown University, Chemistry Department, Washington, DC, 20057, USA
| | - Kaluvu Balaraman
- Georgetown University, Chemistry Department, Washington, DC, 20057, USA
| | - Jeffery A Bertke
- Georgetown University, Chemistry Department, Washington, DC, 20057, USA
| | - Christian Wolf
- Georgetown University, Chemistry Department, Washington, DC, 20057, USA.
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5
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Blanes-Díaz A, Shohel M, Rice NT, Piedmonte I, McDonald MA, Jorabchi K, Kozimor SA, Bertke JA, Nyman M, Knope KE. Synthesis and Characterization of Cerium-Oxo Clusters Capped by Acetylacetonate. Inorg Chem 2023. [PMID: 37792316 DOI: 10.1021/acs.inorgchem.3c02141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Cerium-oxo clusters have applications in fields ranging from catalysis to electronics and also hold the potential to inform on aspects of actinide chemistry. Toward this end, a cerium-acetylacetonate (acac1-) monomeric molecule, Ce(acac)4 (Ce-1), and two acac1--decorated cerium-oxo clusters, [Ce10O8(acac)14(CH3O)6(CH3OH)2]·10.5MeOH (Ce-10) and [Ce12O12(OH)4(acac)16(CH3COO)2]·6(CH3CN) (Ce-12), were prepared and structurally characterized. The Ce(acac)4 monomer contains CeIV. Crystallographic data and bond valence summation values for the Ce-10 and Ce-12 clusters are consistent with both clusters having a mixture of CeIII and CeIV cations. Ce L3-edge X-ray absorption spectroscopy, performed on Ce-10, showed contributions from both CeIII and CeIV. The Ce-10 cluster is built from a hexameric cluster, with six CeIV sites, that is capped by two dimeric CeIII units. By comparison, Ce-12, which formed upon dissolution of Ce-10 in acetonitrile, consists of a central decamer built from edge sharing CeIV hexameric units, and two monomeric CeIII sites that are bound on the outer corners of the inner Ce10 core. Electrospray ionization mass spectrometry data for solutions prepared by dissolving Ce-10 in acetonitrile showed that the major ions could be attributed to Ce10 clusters that differed primarily in the number of acac1-, OH1-, MeO1-, and O2- ligands. Small angle X-ray scattering measurements for Ce-10 dissolved in acetonitrile showed structural units slightly larger than either Ce10 or Ce12 in solution, likely due to aggregation. Taken together, these results suggest that the acetylacetonate supported clusters can support diverse solution-phase speciation in organic solutions that could lead to stabilization of higher order cerium containing clusters, such as cluster sizes that are greater than the Ce10 and Ce12 reported herein.
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Affiliation(s)
- Anamar Blanes-Díaz
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Mohammad Shohel
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Natalie T Rice
- Los Alamos National Laboratory (LANL), P.O. Box 1663, Los Alamos, New Mexico 87545, United States
| | - Ida Piedmonte
- Los Alamos National Laboratory (LANL), P.O. Box 1663, Los Alamos, New Mexico 87545, United States
| | - Morgan A McDonald
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Kaveh Jorabchi
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Stosh A Kozimor
- Los Alamos National Laboratory (LANL), P.O. Box 1663, Los Alamos, New Mexico 87545, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - May Nyman
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Karah E Knope
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
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6
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Ghosh P, Stauffer M, Ahmed ME, Bertke JA, Staples RJ, Warren TH. Thiol and H 2S-Mediated NO Generation from Nitrate at Copper(II). J Am Chem Soc 2023. [PMID: 37224264 PMCID: PMC10367543 DOI: 10.1021/jacs.3c00394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Reduction of nitrate is an essential, yet challenging chemical task required to manage this relatively inert oxoanion in the environment and biology. We show that thiols, ubiquitous reductants in biology, convert nitrate to nitric oxide at a Cu(II) center under mild conditions. The β-diketiminato complex [Cl2NNF6]Cu(κ2-O2NO) engages in O-atom transfer with various thiols (RSH) to form the corresponding copper(II) nitrite [CuII](κ2-O2N) and sulfenic acid (RSOH). The copper(II) nitrite further reacts with RSH to give S-nitrosothiols RSNO and [CuII]2(μ-OH)2 en route to NO formation via [CuII]-SR intermediates. The gasotransmitter H2S also reduces nitrate at copper(II) to generate NO, providing a lens into NO3-/H2S crosstalk. The interaction of thiols with nitrate at copper(II) releases a cascade of N- and S-based signaling molecules in biology.
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Affiliation(s)
- Pokhraj Ghosh
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D. C. 20057, United States
| | - Molly Stauffer
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D. C. 20057, United States
| | - Md Estak Ahmed
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D. C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D. C. 20057, United States
| | - Richard J Staples
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Timothy H Warren
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D. C. 20057, United States
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7
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Ahmed ME, Raghibi Boroujeni M, Ghosh P, Greene C, Kundu S, Bertke JA, Warren TH. Electrocatalytic Ammonia Oxidation by a Low-Coordinate Copper Complex. J Am Chem Soc 2022; 144:21136-21145. [DOI: 10.1021/jacs.2c07977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Md Estak Ahmed
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Mahdi Raghibi Boroujeni
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Pokhraj Ghosh
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Christine Greene
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Subrata Kundu
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695551, India
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Timothy H. Warren
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
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8
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Hosseininasab V, DiMucci IM, Ghosh P, Bertke JA, Chandrasekharan S, Titus CJ, Nordlund D, Freed JH, Lancaster KM, Warren TH. Lewis acid-assisted reduction of nitrite to nitric and nitrous oxides via the elusive nitrite radical dianion. Nat Chem 2022; 14:1265-1269. [PMID: 36064970 PMCID: PMC9633411 DOI: 10.1038/s41557-022-01025-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 07/22/2022] [Indexed: 11/09/2022]
Abstract
Reduction of nitrite anions (NO2-) to nitric oxide (NO), nitrous oxide (N2O) and ultimately dinitrogen (N2) takes place in a variety of environments, including in the soil as part of the biogeochemical nitrogen cycle and in acidified nuclear waste. Nitrite reduction typically takes place within the coordination sphere of a redox-active transition metal. Here we show that Lewis acid coordination can substantially modify the reduction potential of this polyoxoanion to allow for its reduction under non-aqueous conditions (-0.74 V versus NHE). Detailed characterization confirms the formation of the borane-capped radical nitrite dianion (NO22-), which features a N(II) oxidation state. Protonation of the nitrite dianion results in the facile loss of nitric oxide (NO), whereas its reaction with NO results in disproportionation to nitrous oxide (N2O) and nitrite (NO2-). This system connects three redox levels in the global nitrogen cycle and provides fundamental insights into the conversion of NO2- to NO.
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Affiliation(s)
| | - Ida M DiMucci
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Pokhraj Ghosh
- Department of Chemistry, Georgetown University, Washington, DC, USA
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Washington, DC, USA
| | | | - Charles J Titus
- Department of Physics, Stanford University, Stanford, CA, USA
| | - Dennis Nordlund
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Jack H Freed
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Washington, DC, USA.
- Department of Chemistry, Michigan State University, East Lansing, MI, USA.
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9
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Stewart OC, Marwitz AC, Swanson J, Bertke JA, Hartman T, Monteiro JHSK, de Bettencourt-Dias A, Knope KE, Stoll SL. Lanthanide Luminescence and Thermochromic Emission from Soft-Atom Donor Dichalcogenoimidodiphosphinate Ligands. Inorg Chem 2022; 61:15547-15557. [DOI: 10.1021/acs.inorgchem.2c02260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Orlando C. Stewart
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Alexander C. Marwitz
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Joel Swanson
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Tyler Hartman
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Jorge H. S. K. Monteiro
- Department of Chemistry, California Polytechnic State University, Humboldt, Arcata, California 95521, United States
| | | | - Karah E. Knope
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Sarah L. Stoll
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
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10
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Affiliation(s)
- Bryan C. Figula
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Ting-An Chen
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Timothy H. Warren
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
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11
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Ghosh P, Stauffer M, Hosseininasab V, Kundu S, Bertke JA, Cundari TR, Warren TH. NO Coupling at Copper to cis-Hyponitrite: N 2O Formation via Protonation and H-Atom Transfer. J Am Chem Soc 2022; 144:15093-15099. [PMID: 35948086 PMCID: PMC9536194 DOI: 10.1021/jacs.2c04033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Copper nitrite reductases (CuNIRs) convert NO2- to NO as well as NO to N2O under high NO flux at a mononuclear type 2 Cu center. While model complexes illustrate N-N coupling from NO that results in symmetric trans-hyponitrite [CuII]-ONNO-[CuII] complexes, we report NO assembly at a single Cu site in the presence of an external reductant Cp*2M (M = Co, Fe) to give the first copper cis-hyponitrites [Cp*2M]{[CuII](κ2-O2N2)[CuI]}. Importantly, the κ1-N-bound [CuI] fragment may be easily removed by the addition of mild Lewis bases such as CNAr or pyridine to form the spectroscopically similar anion {[CuII](κ2-O2N2)}-. The addition of electrophiles such as H+ to these anionic copper(II) cis-hyponitrites leads to N2O generation with the formation of the dicopper(II)-bis-μ-hydroxide [CuII]2(μ-OH)2. One-electron oxidation of the {[CuII](κ2-O2N2)}- core turns on H-atom transfer reactivity, enabling the oxidation of 9,10-dihydroanthracene to anthracene with concomitant formation of N2O and [CuII]2(μ-OH)2. These studies illustrate both the reductive coupling of NO at a single copper center and a way to harness the strong oxidizing power of nitric oxide via the neutral cis-hyponitrite [Cu](κ2-O2N2).
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Affiliation(s)
- Pokhraj Ghosh
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Washington, D. C. 20057, United States
| | - Molly Stauffer
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Washington, D. C. 20057, United States
| | | | - Subrata Kundu
- Department of Chemistry, Georgetown University, Washington, D. C. 20057, United States
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Washington, D. C. 20057, United States
| | - Thomas R. Cundari
- Department of Chemistry, University of North Texas, Denton, Texas 76203, United States
| | - Timothy H. Warren
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Chemistry, Georgetown University, Washington, D. C. 20057, United States
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12
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Abstract
The one-electron reduction of nitrite (NO2-) to nitric oxide (NO) and ene-diol oxidation are two important biochemical transformations. Employing mononuclear cobalt-nitrite complexes with CoIII and CoII oxidation states, [(Bz3Tren)CoIII(nitrite)2](ClO4) (1) and [(Bz3Tren)CoII(nitrite)](ClO4) (2), this report illustrates NO release coupled to stepwise oxidation of ene-diol antioxidants such as l-ascorbic acid (AH2) and catechol. Analysis of the AH2 end-product reveals that the reaction with complex 1 affords dehydroascorbic acid. Intriguingly, a controlled oxidation of AH2 with complex 2 results in a [CoII]-bound ascorbyl radical-anion (8). Finally, NO release with the concomitant generation of metal-bound 3,5-di-tert-butyl-semiquinone radical anion from the reactions of 3,5-di-tert-butyl-catechol and [(Bz3Tren)MII(nitrite)](ClO4) (2, M = Co; 4, M = Zn) provides mechanistic insights into the cross-talk between nitrite and ene-diols at the metal sites.
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Affiliation(s)
- Shourya Gupta
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM), Thiruvananthapuram 695551, India
| | - Swathy Vijayan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM), Thiruvananthapuram 695551, India
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
| | - Subrata Kundu
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM), Thiruvananthapuram 695551, India
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13
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Wacker JN, Ditter AS, Cary SK, Murray AV, Bertke JA, Seidler GT, Kozimor SA, Knope KE. Reactivity of a Chloride Decorated, Mixed Valent Ce III/IV38-Oxo Cluster. Inorg Chem 2021; 61:193-205. [PMID: 34914366 DOI: 10.1021/acs.inorgchem.1c02705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A cerium-oxo nanocluster capped by chloride ligands, [CeIV38-nCeIIInO56-(n+1)(OH)n+1Cl51(H2O)11]10- (n = 1-24), has been isolated from acidic chloride solutions by using potassium counterions. The crystal structure was elucidated using single crystal X-ray diffraction. At the center of the cluster is a {Ce14} core that exhibits the same fluorite-type structure as bulk CeO2, with eight-coordinate Ce sites bridged by tetrahedral oxo anions. The {Ce14} is further surrounded by a peripheral shell of six tetranuclear {Ce4} subunits that are located on each of the faces of the core to yield the {Ce38} cluster. The surface of the cluster is capped by 51 bridging/terminal chloride ligands and 11 water molecules; the anionic cluster is charge balanced by potassium counterions that exist in the outer coordination sphere. While assignment of the Ce oxidation state by bond valence summation was ambiguous, Ce L3-edge X-ray absorption, X-ray photoelectron, and UV-vis-NIR absorption results were consistent with a CeIII/CeIV cluster. Systematic changes in the XANES and UV-vis-NIR absorption spectra over time pointed to reactivity of the cluster upon exposure to air. These changes were examined using single crystal X-ray diffraction, and a clear single-crystal-to-single-crystal transformation was captured; an overall loss of surface-bound chlorides and water molecules as well as new μ2-OH sites was observed on the cluster surface. This work provides a rare snapshot of metal oxide cluster reactivity. The results may hold implications for understanding the physical and chemical properties of ceria nanoparticles and provide insight into the behavior of other metal-oxo clusters of significant technological and environmental interest.
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Affiliation(s)
- Jennifer N Wacker
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Alexander S Ditter
- Los Alamos National Laboratory (LANL), P.O. Box 1663, Los Alamos, New Mexico 87545, United States.,Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195, United States
| | - Samantha K Cary
- Los Alamos National Laboratory (LANL), P.O. Box 1663, Los Alamos, New Mexico 87545, United States
| | - Aphra V Murray
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Gerald T Seidler
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195, United States
| | - Stosh A Kozimor
- Los Alamos National Laboratory (LANL), P.O. Box 1663, Los Alamos, New Mexico 87545, United States
| | - Karah E Knope
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
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14
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Marwitz AC, Nicholas AD, Breuer LM, Bertke JA, Knope KE. Harnessing Bismuth Coordination Chemistry to Achieve Bright, Long-Lived Organic Phosphorescence. Inorg Chem 2021; 60:16840-16851. [PMID: 34628857 DOI: 10.1021/acs.inorgchem.1c02748] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new bismuth(III)-organic compound, Hphen[Bi2(HPDC)2(PDC)2(NO3)]·4H2O (Bi-1; PDC = 2,6-pyridinedicarboxylate and phen = 1,10-phenanthroline), was synthesized, and the structure was determined by single-crystal X-ray diffraction. The compound was found to display bright-blue-green phosphorescence in the solid state under UV irradiation, with a luminescent lifetime of 1.776 ms at room temperature. The room temperature and low-temperature (77 K) emission spectra exhibited the vibronic structure characteristic of Hphen phosphorescence. Time-dependent density functional theory studies showed that the excitation pathway arises from an energy transfer from the dimeric structural unit to Hphen, with participation from a nine-coordinate Bi center. The triplet state of Hphen is believed to be stabilized via supramolecular interactions, which, when coupled with the heavy-atom effect induced by Bi, leads to the observed long-lived luminescence. The compound displayed a solid-state quantum yield of over 27%. To the best of our knowledge, this is the first such compound to exhibit phenanthrolinium phosphorescence with such long-lived, room temperature lifetimes in the solid state. To further elucidate the energy-transfer mechanism, Ln3+ (Ln = Eu, Tb, Sm) ions were successfully doped into the parent compound, and the resulting materials exhibited dual emission from Hphen and Ln, promoting tunability of the emission color.
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Affiliation(s)
- Alexander C Marwitz
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Aaron D Nicholas
- National Security Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States
| | - Leticia M Breuer
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Karah E Knope
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
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15
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Gardner EJ, Marguet SC, Cobb CR, Pham DM, Beringer JAM, Bertke JA, Shafaat HS, Warren TH. Uncovering Redox Non-innocent Hydrogen-Bonding in Cu(I)-Diazene Complexes. J Am Chem Soc 2021; 143:15960-15974. [PMID: 34546737 DOI: 10.1021/jacs.1c04108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The life-sustaining reduction of N2 to NH3 is thermoneutral yet kinetically challenged by high-energy intermediates such as N2H2. Exploring intramolecular H-bonding as a potential strategy to stabilize diazene intermediates, we employ a series of [xHetTpCu]2(μ-N2H2) complexes that exhibit H-bonding between pendant aromatic N-heterocycles (xHet) such as pyridine and a bridging trans-N2H2 ligand at copper(I) centers. X-ray crystallography and IR spectroscopy clearly reveal H-bonding in [pyMeTpCu]2(μ-N2H2) while low-temperature 1H NMR studies coupled with DFT analysis reveals a dynamic equilibrium between two closely related, symmetric H-bonded structural motifs. Importantly, the xHet pendant negligibly influences the electronic structure of xHetTpCuI centers in xHetTpCu(CNAr2,6-Me2) complexes that lack H-bonding as judged by nearly indistinguishable ν(CN) frequencies (2113-2117 cm-1). Nonetheless, H-bonding in the corresponding [xHetTpCu]2(μ-N2H2) complexes results in marked changes in ν(NN) (1398-1419 cm-1) revealed through resonance Raman studies. Due to the closely matched N-H BDEs of N2H2 and the pyH0 cation radical, the aromatic N-heterocyclic pendants may encourage partial H-atom transfer (HAT) from N2H2 to xHet through redox-non-innocent H-bonding in [xHetTpCu]2(μ-N2H2). DFT studies reveal modest thermodynamic barriers for concerted transfer of both H-atoms of coordinated N2H2 to the xHet pendants to generate tautomeric [xHetHTpCu]2(μ-N2) complexes, identifying metal-assisted concerted dual HAT as a thermodynamically favorable pathway for N2/N2H2 interconversion.
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Affiliation(s)
- Evan J Gardner
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Sean C Marguet
- The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Caitlyn R Cobb
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Dominic M Pham
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Josalyne A M Beringer
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Hannah S Shafaat
- The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
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16
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Watts TA, Price LS, Price SL, Niederberger SM, Bertke JA, Swift JA. The Crystal Structure of 5‐Aminouracil and the Ambiguity of Alternative Polymorphs. Isr J Chem 2021. [DOI: 10.1002/ijch.202100062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Taylor A. Watts
- Department of Chemistry Georgetown University 37th and O Sts NW Washington DC 20057–1227 USA
| | - Louise S. Price
- Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK
| | - Sarah L. Price
- Department of Chemistry University College London 20 Gordon Street London WC1H 0AJ UK
| | - Sara M. Niederberger
- Department of Chemistry Georgetown University 37th and O Sts NW Washington DC 20057–1227 USA
| | - Jeffery A. Bertke
- Department of Chemistry Georgetown University 37th and O Sts NW Washington DC 20057–1227 USA
| | - Jennifer A. Swift
- Department of Chemistry Georgetown University 37th and O Sts NW Washington DC 20057–1227 USA
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17
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Abstract
NO and H2 S serve as signaling molecules in biology with intertwined reactivity. HSNO and HSSNO with their conjugate bases - SNO and - SSNO form in the reaction of H2 S with NO as well as S-nitrosothiols (RSNO) and nitrite (NO2 - ) that serve as NO reservoirs. While HSNO and HSSNO are elusive, their conjugate bases form isolable zinc complexes Ph,Me TpZn(SNO) and Ph,Me TpZn(SSNO) supported by tris(pyrazolyl)borate ligands. Reaction of Na(15-C-5)SSNO with Ph,Me TpZn(ClO4 ) provides Ph,Me TpZn(SSNO) that undergoes S-atom removal by PEt3 to give Ph,Me TpZn(SNO) and S=PEt3 . Unexpectedly stable at room temperature, these Zn-SNO and Zn-SSNO complexes release NO upon heating. Ph,Me TpZn(SNO) and Ph,Me TpZn(SSNO) quickly react with acidic thiols such as C6 F5 SH to form N2 O and NO, respectively. Increasing the thiol basicity in p-substituted aromatic thiols 4-X ArSH in the reaction with Ph,Me TpZn(SNO) turns on competing S-nitrosation to form Ph,Me TpZn-SH and RSNO, the latter a known precursor for NO.
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Affiliation(s)
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227, Washington, DC, 20057-1227, USA
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 571227, Washington, DC, 20057-1227, USA
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18
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Affiliation(s)
| | - Jeffery A. Bertke
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | - Timothy H. Warren
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
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19
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Ayscue RL, Vallet V, Bertke JA, Réal F, Knope KE. Structure-Property Relationships in Photoluminescent Bismuth Halide Organic Hybrid Materials. Inorg Chem 2021; 60:9727-9744. [PMID: 34128679 DOI: 10.1021/acs.inorgchem.1c01025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Seven novel bismuth(III)-halide phases, Bi2Cl6(terpy)2·0.5(H2O) (1), Bi2Cl4(terpy)2(k2-TC)2(2) (TC = 2-thiophene monocarboxylate), BiCl(terpy)(k2-TC)2 (3A-Cl), BiBr(terpy)(k2-TC)2 (3A-Br), BiCl(terpy)(k2-TC)2 (3B-Cl), [BiCl(terpy)(k2-TC)2][Bi(terpy)(k2-TC)3]·0.55(TCA) (4), [BiBr3(terpy)(MeOH)] (5), and [BiBr2(terpy)(k2-TC)][BiBr1.16(terpy)(k2-TC)1.84] (6), were prepared under mild synthetic conditions from methanolic/aqueous solutions containing BiX3 (X = Cl, Br) and 2,2':6',2″-terpyridine (terpy) and/or 2-thiophene monocarboxylic acid (TCA). A heterometallic series, 3A-Bi1-xEuxCl, with the general formula Bi1-xEuxCl(terpy)(k2-TC)2 (x = 0.001, 0.005, 0.01, 0.05) was also prepared through trace Eu doping of the 3A-Cl phase. The structures were determined through single-crystal X-ray diffraction and are built from a range of molecular units including monomeric and dimeric complexes. The solid-state photoluminescent properties of the compounds were examined through steady-state and time-resolved methods. While the homometallic phases exhibited broad green to yellow emission, the heterometallic phases displayed yellow, orange, and red emission that can be attributed to the simultaneous ligand/Bi-halide and Eu centered emissions. Photoluminescent color tuning was achieved by controlling the relative intensities of these concurrent emissions through compositional modifications including the Eu doping percentage. Notably, all emissive homo- and heterometallic phases exhibited rare visible excitation pathways that based on theoretical quantum mechanical calculations are attributed to halide-metal to ligand charge transfer (XMLCT). Through a combined experimental and computational approach, fundamental insight into the structure-property relationships within these Bi halide organic hybrid materials is provided.
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Affiliation(s)
- R Lee Ayscue
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, DC 20057, United States
| | - Valérie Vallet
- Université de Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, 59000 Lille, France
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, DC 20057, United States
| | - Florent Réal
- Université de Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, 59000 Lille, France
| | - Karah E Knope
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, DC 20057, United States
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20
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Stauffer M, Sakhaei Z, Greene C, Ghosh P, Bertke JA, Warren TH. Mechanism of O-Atom Transfer from Nitrite: Nitric Oxide Release at Copper(II). Inorg Chem 2021; 60:15968-15974. [PMID: 34184870 DOI: 10.1021/acs.inorgchem.1c00625] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nitric oxide (NO) is a key signaling molecule in health and disease. While nitrite acts as a reservoir of NO activity, mechanisms for NO release require further understanding. A series of electronically varied β-diketiminatocopper(II) nitrite complexes [CuII](κ2-O2N) react with a range of electronically tuned triarylphosphines PArZ3 that release NO with the formation of O═PArZ3. Second-order rate constants are largest for electron-poor copper(II) nitrite and electron-rich phosphine pairs. Computational analysis reveals a transition-state structure energetically matched with experimentally determined activation barriers. The production of NO follows a pathway that involves nitrite isomerization at CuII from κ2-O2N to κ1-NO2 followed by O-atom transfer (OAT) to form O═PArZ3 and [CuI]-NO that releases NO upon PArZ3 binding at CuI to form [CuI]-PArZ3. These findings illustrate important mechanistic considerations involved in NO formation from nitrite via OAT.
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Affiliation(s)
- Molly Stauffer
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Zeinab Sakhaei
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Christine Greene
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Pokhraj Ghosh
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, D.C. 20057, United States
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21
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Wacker JN, Nicholas AD, Vasiliu M, Marwitz AC, Bertke JA, Dixon DA, Knope KE. Impact of Noncovalent Interactions on the Structural Chemistry of Thorium(IV)-Aquo-Chloro Complexes. Inorg Chem 2021; 60:6375-6390. [PMID: 33885290 DOI: 10.1021/acs.inorgchem.1c00099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Five novel tetravalent thorium (Th) compounds that consist of Th(H2O)xCly structural units were isolated from acidic aqueous solutions using a series of nitrogen-containing heterocyclic hydrogen (H) bond donors. Taken together with three previously reported phases, the compounds provide a series of monomeric ThIV complexes wherein the effects of noncovalent interactions (and H-bond donor identity) on Th structural chemistry can be examined. Seven distinct structural units of the general formulas [Th(H2O)xCl8-x]x-4 (x = 2, 4) and [Th(H2O)xCl9-x]x-5 (x = 5-7) are described. The complexes range from chloride-deficient [Th(H2O)7Cl2]2+ to chloride-rich [Th(H2O)2Cl6]2- species, and theory was used to understand the relative energies that separate complexes within this series via the stepwise chloride addition to an aquated Th cation. Electronic structure theory predicted the reaction energies of chloride addition and release of water through a series of transformations, generally highlighting an energetic driving force for chloride complexation. To probe the role of the counterion in the stabilization of these complexes, electrostatic potential (ESP) surfaces were calculated. The ESP surfaces indicated a dependence of the chloride distribution about the Th metal center on the pKa of the countercation, highlighting the directing effects of noncovalent interactions (e.g., Hbonding) on Th speciation.
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Affiliation(s)
- Jennifer N Wacker
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Aaron D Nicholas
- Department of Chemistry, The George Washington University, Washington, D.C. 20052, United States
| | - Monica Vasiliu
- Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Alexander C Marwitz
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
| | - David A Dixon
- Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Karah E Knope
- Department of Chemistry, Georgetown University, Washington, D.C. 20057, United States
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22
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Jayasooriya IU, Bakhoda A(G, Palmer R, Ng K, Khachemoune NL, Bertke JA, Warren TH. Copper( ii) ketimides in sp 3 C–H amination. Chem Sci 2021; 12:15733-15738. [PMID: 35003605 PMCID: PMC8654034 DOI: 10.1039/d1sc01990b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 10/29/2021] [Indexed: 01/06/2023] Open
Abstract
Commercially available benzophenone imine (HN
Created by potrace 1.16, written by Peter Selinger 2001-2019
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CPh2) reacts with β-diketiminato copper(ii) tert-butoxide complexes [CuII]–OtBu to form isolable copper(ii) ketimides [CuII]–NCPh2. Structural characterization of the three coordinate copper(ii) ketimide [Me3NN]Cu–NCPh2 reveals a short Cu-Nketimide distance (1.700(2) Å) with a nearly linear Cu–N–C linkage (178.9(2)°). Copper(ii) ketimides [CuII]–NCPh2 readily capture alkyl radicals R˙ (PhCH(˙)Me and Cy˙) to form the corresponding R–NCPh2 products in a process that competes with N–N coupling of copper(ii) ketimides [CuII]–NCPh2 to form the azine Ph2CN–NCPh2. Copper(ii) ketimides [CuII]–NCAr2 serve as intermediates in catalytic sp3 C–H amination of substrates R–H with ketimines HNCAr2 and tBuOOtBu as oxidant to form N-alkyl ketimines R–NCAr2. This protocol enables the use of unactivated sp3 C–H bonds to give R–NCAr2 products easily converted to primary amines R–NH2via simple acidic deprotection. Commercially available benzophenone imine (HNCPh2) reacts with β-diketiminato copper(ii) tert-butoxide complexes [CuII]–OtBu to form isolable copper(ii) ketimides [CuII]–NCPh2 that serve as intermediates in catalytic sp3 C−H amination via radical relay.![]()
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Affiliation(s)
- Isuri U. Jayasooriya
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | | | - Rachel Palmer
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Kristi Ng
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Nour L. Khachemoune
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Timothy H. Warren
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
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23
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Adcock AK, Marwitz AC, Sanz LA, Lee Ayscue R, Bertke JA, Knope KE. Synthesis, structural characterization, and luminescence properties of heteroleptic bismuth-organic compounds. CrystEngComm 2021. [DOI: 10.1039/d1ce01242h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis and photoluminescent properties of four bismuth-organic compounds, their lanthanide doped analogs, and an isostructural europium complex are reported.
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Affiliation(s)
- Alyssa K. Adcock
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA
| | - Alexander C. Marwitz
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA
| | - Lulio A. Sanz
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA
| | - R. Lee Ayscue
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA
| | - Karah E. Knope
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA
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24
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Bakhoda A, Okoromoba OE, Greene C, Boroujeni MR, Bertke JA, Warren TH. Three-Coordinate Copper(II) Alkynyl Complex in C-C Bond Formation: The Sesquicentennial of the Glaser Coupling. J Am Chem Soc 2020; 142:18483-18490. [PMID: 32956589 DOI: 10.1021/jacs.0c07137] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Copper(II) alkynyl species are proposed as key intermediates in numerous Cu-catalyzed C-C coupling reactions. Supported by a β-diketiminate ligand, the three-coordinate copper(II) alkynyl [CuII]-C≡CAr (Ar = 2,6-Cl2C6H3) forms upon reaction of the alkyne H-C≡CAr with the copper(II) tert-butoxide complex [CuII]-OtBu. In solution, this [CuII]-C≡CAr species cleanly transforms to the Glaser coupling product ArC≡C-C≡CAr and [CuI](solvent). Addition of nucleophiles R'C≡C-Li (R' = aryl, silyl) and Ph-Li to [CuII]-C≡CAr affords the corresponding Csp-Csp and Csp-Csp2 coupled products RC≡C-C≡CAr and Ph-C≡CAr with concomitant generation of [CuI](solvent) and {[CuI]-C≡CAr}-, respectively. Supported by density functional theory (DFT) calculations, redox disproportionation forms [CuIII](C≡CAr)(R) species that reductively eliminate R-C≡CAr products. [CuII]-C≡CAr also captures the trityl radical Ph3C· to give Ph3C-C≡CAr. Radical capture represents the key Csp-Csp3 bond-forming step in the copper-catalyzed C-H functionalization of benzylic substrates R-H with alkynes H-C≡CR' (R' = (hetero)aryl, silyl) that provide Csp-Csp3 coupled products R-C≡CR via radical relay with tBuOOtBu as oxidant.
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Affiliation(s)
- Abolghasem Bakhoda
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
| | - Otome E Okoromoba
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
| | - Christine Greene
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
| | - Mahdi Raghibi Boroujeni
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, District of Columbia 20057, United States
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25
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Adcock AK, Ayscue RL, Breuer LM, Verwiel CP, Marwitz AC, Bertke JA, Vallet V, Réal F, Knope KE. Synthesis and photoluminescence of three bismuth(III)-organic compounds bearing heterocyclic N-donor ligands. Dalton Trans 2020; 49:11756-11771. [PMID: 32803206 DOI: 10.1039/d0dt02360d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Three bismuth(iii)-organic compounds, [Bi4Cl8(PDC)2(phen)4]·2MeCN (1), [BiCl3(phen)2] (2), and [Bi2Cl6(terpy)2] (3), were prepared from solvothermal reactions of bismuth chloride, 2,6-pyridinedicarboxylic acid (H2PDC), and 1,10-phenanthroline (phen) or 2,2';6',2''-terpyridine (terpy). The structures were determined through single crystal X-ray diffraction and the compounds were further characterized via powder X-ray diffraction, Raman and infrared spectroscopy, and thermogravimetric analysis. The photoluminescence properties of the solid-state materials were assessed using steady state and time-dependent techniques to obtain excitation and emission profiles as well as lifetimes. The compounds exhibit visible emission ranging from the yellow-green to orange region upon UV excitation. Theoretical quantum mechanical calculations aimed at elucidating the observed emissive behavior show that the transitions can be assigned as predominantly ligand-to-ligand and ligand-to-metal charge transfer transitions. The solid-state structural chemistry, spectroscopic properties, and luminescence behavior of the bismuth compounds are presented herein.
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Affiliation(s)
- Alyssa K Adcock
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
| | - R Lee Ayscue
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
| | - Leticia M Breuer
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
| | - Chloe P Verwiel
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
| | - Alexander C Marwitz
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
| | - Valérie Vallet
- Université Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers, Atomes et Molécules, F-59000 Lille, France
| | - Florent Réal
- Université Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers, Atomes et Molécules, F-59000 Lille, France
| | - Karah E Knope
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, D.C. 20057, USA.
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26
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Murray AV, Vanagas NA, Wacker JN, Bertke JA, Knope KE. From Isolated Molecular Complexes to Extended Networks: Synthesis and Characterization of Thorium Furanmono‐ and Dicarboxylates. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Aphra V. Murray
- Department of Chemistry Georgetown University 37 and O Streets NW Washington D.C. 20057 USA
| | - Nicole A. Vanagas
- Department of Chemistry Georgetown University 37 and O Streets NW Washington D.C. 20057 USA
| | - Jennifer N. Wacker
- Department of Chemistry Georgetown University 37 and O Streets NW Washington D.C. 20057 USA
| | - Jeffery A. Bertke
- Department of Chemistry Georgetown University 37 and O Streets NW Washington D.C. 20057 USA
| | - Karah E. Knope
- Department of Chemistry Georgetown University 37 and O Streets NW Washington D.C. 20057 USA
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27
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Hosseininasab V, McQuilken AC, Bakhoda A(G, Bertke JA, Timerghazin QK, Warren TH. Lewis Acid Coordination Redirects S‐Nitrosothiol Signaling Output. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001450] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Alison C. McQuilken
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | | | - Jeffery A. Bertke
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | - Qadir K. Timerghazin
- Department of Chemistry Marquette University P.O. Box 1881 Milwaukee WI 53201-1881 USA
| | - Timothy H. Warren
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
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28
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Hosseininasab V, McQuilken AC, Bakhoda AG, Bertke JA, Timerghazin QK, Warren TH. Lewis Acid Coordination Redirects S-Nitrosothiol Signaling Output. Angew Chem Int Ed Engl 2020; 59:10854-10858. [PMID: 32090399 PMCID: PMC7385465 DOI: 10.1002/anie.202001450] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Indexed: 01/02/2023]
Abstract
S-Nitrosothiols (RSNOs) serve as air-stable reservoirs for nitric oxide in biology. While copper enzymes promote NO release from RSNOs by serving as Lewis acids for intramolecular electron-transfer, redox-innocent Lewis acids separate these two functions to reveal the effect of coordination on structure and reactivity. The synthetic Lewis acid B(C6 F5 )3 coordinates to the RSNO oxygen atom, leading to profound changes in the RSNO electronic structure and reactivity. Although RSNOs possess relatively negative reduction potentials, B(C6 F5 )3 coordination increases their reduction potential by over 1 V into the physiologically accessible +0.1 V vs. NHE. Outer-sphere chemical reduction gives the Lewis acid stabilized hyponitrite dianion trans-[LA-O-N=N-O-LA]2- [LA=B(C6 F5 )3 ], which releases N2 O upon acidification. Mechanistic and computational studies support initial reduction to the [RSNO-B(C6 F5 )3 ] radical anion, which is susceptible to N-N coupling prior to loss of RSSR.
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Affiliation(s)
| | - Alison C McQuilken
- Department of Chemistry, Georgetown University, Box 571227, Washington, DC, 20057-1227, USA
| | - Abolghasem Gus Bakhoda
- Department of Chemistry, Georgetown University, Box 571227, Washington, DC, 20057-1227, USA
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, Box 571227, Washington, DC, 20057-1227, USA
| | - Qadir K Timerghazin
- Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, WI, 53201-1881, USA
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 571227, Washington, DC, 20057-1227, USA
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29
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Affiliation(s)
- R. Lee Ayscue
- Department of Chemistry, Georgetown University, 37th and O Streets, Northwest, Washington, DC 20057, United States
| | - Chloe P. Verwiel
- Department of Chemistry, Georgetown University, 37th and O Streets, Northwest, Washington, DC 20057, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets, Northwest, Washington, DC 20057, United States
| | - Karah E. Knope
- Department of Chemistry, Georgetown University, 37th and O Streets, Northwest, Washington, DC 20057, United States
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30
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Affiliation(s)
- Abolghasem Gus Bakhoda
- Georgetown University, Department of Chemistry, Washington, District of Columbia 20057-1227, United States
| | - Stefan Wiese
- Georgetown University, Department of Chemistry, Washington, District of Columbia 20057-1227, United States
| | - Christine Greene
- Georgetown University, Department of Chemistry, Washington, District of Columbia 20057-1227, United States
| | - Bryan C. Figula
- Georgetown University, Department of Chemistry, Washington, District of Columbia 20057-1227, United States
| | - Jeffery A. Bertke
- Georgetown University, Department of Chemistry, Washington, District of Columbia 20057-1227, United States
| | - Timothy H. Warren
- Georgetown University, Department of Chemistry, Washington, District of Columbia 20057-1227, United States
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31
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Vanagas NA, Higgins RF, Wacker JN, Asuigui DRC, Warzecha E, Kozimor SA, Stoll SL, Schelter EJ, Bertke JA, Knope KE. Mononuclear to Polynuclear U
IV
Structural Units: Effects of Reaction Conditions on U‐Furoate Phase Formation. Chemistry 2020; 26:5872-5886. [DOI: 10.1002/chem.201905759] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Nicole A. Vanagas
- Department of Chemistry Georgetown University 37th and O Streets NW Washington, D.C. 20057 United States
| | - Robert F. Higgins
- P. Roy and Diana T. Vagelos Laboratories Department of Chemistry University of Pennsylvania 231 S. 34th Street Philadelphia Pennsylvania 19104 United States
| | - Jennifer N. Wacker
- Department of Chemistry Georgetown University 37th and O Streets NW Washington, D.C. 20057 United States
- Los Alamos National Laboratory Los Alamos New Mexico 87545 United States
| | - Dane Romar C. Asuigui
- Department of Chemistry Georgetown University 37th and O Streets NW Washington, D.C. 20057 United States
| | - Evan Warzecha
- Department of Chemistry and Biochemistry Florida State University Tallahassee Florida 32306 United States
| | - Stosh A. Kozimor
- Los Alamos National Laboratory Los Alamos New Mexico 87545 United States
| | - Sarah L. Stoll
- Department of Chemistry Georgetown University 37th and O Streets NW Washington, D.C. 20057 United States
| | - Eric J. Schelter
- P. Roy and Diana T. Vagelos Laboratories Department of Chemistry University of Pennsylvania 231 S. 34th Street Philadelphia Pennsylvania 19104 United States
| | - Jeffery A. Bertke
- Department of Chemistry Georgetown University 37th and O Streets NW Washington, D.C. 20057 United States
| | - Karah E. Knope
- Department of Chemistry Georgetown University 37th and O Streets NW Washington, D.C. 20057 United States
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32
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Mondal A, Reddy KP, Bertke JA, Kundu S. Phenol Reduces Nitrite to NO at Copper(II): Role of a Proton-Responsive Outer Coordination Sphere in Phenol Oxidation. J Am Chem Soc 2020; 142:1726-1730. [PMID: 31910624 DOI: 10.1021/jacs.9b11597] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In the view of physiological significance, the transition-metal-mediated routes for nitrite (NO2-) to nitric oxide (NO) conversion and phenol oxidation are of prime importance. Probing the reactivity of substituted phenols toward the nitritocopper(II) cryptate complex [mC]Cu(κ2-O2N)(ClO4) (1a), this report illustrates NO release from nitrite at copper(II) following a proton-coupled electron transfer (PCET) pathway. Moreover, a different protonated state of 1a with a proton hosted in the outer coordination sphere, [mCH]Cu(κ2-O2N)(ClO4)2 (3), also reacts with substituted phenols via primary electron transfer from the phenol. Intriguingly, the alternative mechanism operative because of the presence of a proton at the remote site in 3 facilitates an unusual anaerobic pathway for phenol nitration.
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Affiliation(s)
- Aditesh Mondal
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM) , Thiruvananthapuram 695551 , India
| | - Kiran P Reddy
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM) , Thiruvananthapuram 695551 , India
| | - Jeffery A Bertke
- Department of Chemistry , Georgetown University , Box 571227-1227, Washington , D.C. 20057 , United States
| | - Subrata Kundu
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM) , Thiruvananthapuram 695551 , India
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33
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Gardner EJ, Cobb CR, Bertke JA, Warren TH. Tris(pyrazolyl)borate Copper Hydroxide Complexes Featuring Tunable Intramolecular H-Bonding. Inorg Chem 2019; 58:11248-11255. [DOI: 10.1021/acs.inorgchem.9b01991] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Evan J. Gardner
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Caitlyn R. Cobb
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
| | - Timothy H. Warren
- Department of Chemistry, Georgetown University, Box 51277-1227, Washington, D.C. 20057, United States
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34
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Wacker JN, Vasiliu M, Colliard I, Ayscue RL, Han SY, Bertke JA, Nyman M, Dixon DA, Knope KE. Monomeric and Trimeric Thorium Chlorides Isolated from Acidic Aqueous Solution. Inorg Chem 2019; 58:10871-10882. [DOI: 10.1021/acs.inorgchem.9b01238] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Jennifer N. Wacker
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Monica Vasiliu
- Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Ian Colliard
- Oregon State University, Department of Chemistry, Corvallis, Oregon 97331, United States
| | - R. Lee Ayscue
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Sae Young Han
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - May Nyman
- Oregon State University, Department of Chemistry, Corvallis, Oregon 97331, United States
| | - David A. Dixon
- Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Karah E. Knope
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
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35
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Jackson BJ, Najera DC, Matson EM, Woods TJ, Bertke JA, Fout AR. Synthesis and Characterization of (DIPPCCC)Fe Complexes: A Zwitterionic Metalation Method and CO2 Reactivity. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00271] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Bailey J. Jackson
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Daniel C. Najera
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Ellen M. Matson
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Toby J. Woods
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Jeffery A. Bertke
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Alison R. Fout
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
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36
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Bertke JA, Wacker JN, Knope KE. Oxidation state assignment in cerium nanoclusters: conflicting conclusions from single-crystal X-ray diffraction and spectroscopic data. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s010876731909706x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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37
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Wacker JN, Han SY, Murray AV, Vanagas NA, Bertke JA, Sperling JM, Surbella RG, Knope KE. From Thorium to Plutonium: Trends in Actinide(IV) Chloride Structural Chemistry. Inorg Chem 2019; 58:10578-10591. [DOI: 10.1021/acs.inorgchem.9b01279] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Jennifer N. Wacker
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Sae Young Han
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Aphra V. Murray
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Nicole A. Vanagas
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
| | - Joseph M. Sperling
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Robert G. Surbella
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States
| | - Karah E. Knope
- Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States
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38
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Chattopadhyay T, B S A, Gupta S, S A, Bertke JA, Kundu S. NO x- anion recognition by bimetallic cryptates: selectivity for nitrite over nitrate. Dalton Trans 2019; 48:7085-7089. [PMID: 30758367 DOI: 10.1039/c8dt04971h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Nitrate and nitrite anions have multifaceted impacts on the environment and human health. We herein report selective recognition of nitrite over nitrate anion inside the cavity of bimetallic azacryptates having p-xylyl spacers. This work reveals a number of binding interactions which play pivotal roles in nitrite anion recognition by rigid metal cryptates.
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Affiliation(s)
- Taraknath Chattopadhyay
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695551, India.
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39
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Dahanayake V, Pornrungroj C, Pablico-Lansigan M, Hickling WJ, Lyons T, Lah D, Lee Y, Parasido E, Bertke JA, Albanese C, Rodriguez O, Van Keuren E, Stoll SL. Paramagnetic Clusters of Mn 3(O 2CCH 3) 6(Bpy) 2 in Polyacrylamide Nanobeads as a New Design Approach to a T 1- T 2 Multimodal Magnetic Resonance Imaging Contrast Agent. ACS Appl Mater Interfaces 2019; 11:18153-18164. [PMID: 30964631 PMCID: PMC8515904 DOI: 10.1021/acsami.9b03216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
There is an increasing need for gadolinium-free magnetic resonance imaging (MRI) contrast agents, particularly for patients suffering from chronic kidney disease. Using a cluster-nanocarrier combination, we have identified a novel approach to the design of biomedical nanomaterials and report here the criteria for the cluster and the nanocarrier and the advantages of this combination. We have investigated the relaxivity of the following manganese oxo clusters: the parent cluster Mn3(O2CCH3)6(Bpy)2 (1) where Bpy = 2,2'-bipyridine and three new analogs, Mn3(O2CC6H4CH═CH2)6(Bpy)2 (2), Mn3(O2CC(CH3)═CH2)6(Bpy)2 (3), and Mn3O(O2CCH3)6(Pyr)2 (4) where Pyr = pyridine. The parent cluster, Mn3(O2CCH3)6(Bpy)2 (1), had impressive relaxivity ( r1 = 6.9 mM-1 s-1, r2 = 125 mM-1 s-1) and was found to be the most amenable for the synthesis of cluster-nanocarrier nanobeads. Using the inverse miniemulsion polymerization technique (1) in combination with the hydrophilic monomer acrylamide, we synthesized nanobeads (∼125 nm diameter) with homogeneously dispersed clusters within the polyacrylamide matrix (termed Mn3Bpy-PAm). The nanobeads were surface-modified by co-polymerization with an amine-functionalized monomer. This enabled various postsynthetic modifications, for example, to attach a near-IR dye, Cyanine7, as well as a targeting agent. When evaluated as a potential multimodal MRI contrast agent, high relaxivity and contrast were observed with r1 = 54.4 mM-1 s-1 and r2 = 144 mM-1 s-1, surpassing T1 relaxivity of clinically used Gd-DTPA chelates as well as comparable T2 relaxivity to iron oxide microspheres. Physicochemical properties, cellular uptake, and impacts on cell viability were also investigated.
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Affiliation(s)
- Vidumin Dahanayake
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
| | - Chanon Pornrungroj
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
- IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Michele Pablico-Lansigan
- Department of Chemistry, American University, 4400 Massachusetts Avenue, NW, Washington, DC 20016, United States
| | - William J. Hickling
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
| | - Trevor Lyons
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
| | - David Lah
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
| | - Yichien Lee
- Department of Oncology, Lombardi Comprehensive Cancer Center and Center for Translational Imaging, Georgetown University Medical Center, Washington, DC 20057, United States
| | - Erika Parasido
- Department of Oncology, Lombardi Comprehensive Cancer Center and Center for Translational Imaging, Georgetown University Medical Center, Washington, DC 20057, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
| | - Christopher Albanese
- Department of Oncology, Lombardi Comprehensive Cancer Center and Center for Translational Imaging, Georgetown University Medical Center, Washington, DC 20057, United States
| | - Olga Rodriguez
- Department of Oncology, Lombardi Comprehensive Cancer Center and Center for Translational Imaging, Georgetown University Medical Center, Washington, DC 20057, United States
| | - Edward Van Keuren
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
| | - Sarah L. Stoll
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets NW, Washington, DC 20057, United States
- Corresponding Author:
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40
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Chaudhuri S, Mohanan M, Willems AV, Bertke JA, Gavvalapalli N. β-Strand inspired bifacial π-conjugated polymers. Chem Sci 2019; 10:5976-5982. [PMID: 31360404 PMCID: PMC6566302 DOI: 10.1039/c9sc01724k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/09/2019] [Indexed: 11/21/2022] Open
Abstract
Access to diverse, relatively high molecular weight soluble linear polymers without pendant solubilizing chains is the key to solution state synthesis of structurally diverse nanoribbons of conjugated materials. However, realizing soluble 1D-π-conjugated polymers without pendant solubilizing chains is a daunting task. Herein, inspired from the polypeptide β-strand architecture, we have designed and developed novel bifacial π-conjugated polymers (M n: ca. 24 kDa) that are soluble (ca. 70 to >250 mM) despite the absence of pendant solubilizing chains. The impact of varying the bifacial monomer height on polymer solubility, optical properties, and interactions with small molecules is reported.
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Affiliation(s)
- Saikat Chaudhuri
- Department of Chemistry , Institute for Soft Matter Synthesis and Metrology , Georgetown University , 3700 O st NW , Washington , D.C. 20057 , USA .
| | - Manikandan Mohanan
- Department of Chemistry , Institute for Soft Matter Synthesis and Metrology , Georgetown University , 3700 O st NW , Washington , D.C. 20057 , USA .
| | - Andreas V Willems
- Department of Chemistry , Institute for Soft Matter Synthesis and Metrology , Georgetown University , 3700 O st NW , Washington , D.C. 20057 , USA .
| | - Jeffery A Bertke
- Department of Chemistry , Institute for Soft Matter Synthesis and Metrology , Georgetown University , 3700 O st NW , Washington , D.C. 20057 , USA .
| | - Nagarjuna Gavvalapalli
- Department of Chemistry , Institute for Soft Matter Synthesis and Metrology , Georgetown University , 3700 O st NW , Washington , D.C. 20057 , USA .
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41
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Bakhoda A(G, Jiang Q, Badiei YM, Bertke JA, Cundari TR, Warren TH. Copper‐Catalyzed C(sp
3
)−H Amidation: Sterically Driven Primary and Secondary C−H Site‐Selectivity. Angew Chem Int Ed Engl 2019; 58:3421-3425. [DOI: 10.1002/anie.201810556] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Indexed: 12/20/2022]
Affiliation(s)
| | - Quan Jiang
- Department of Chemistry Center for Advanced Scientific Computing and Modeling (CASCaM) University of North Texas Denton TX 76203 USA
| | - Yosra M. Badiei
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | - Jeffery A. Bertke
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | - Thomas R. Cundari
- Department of Chemistry Center for Advanced Scientific Computing and Modeling (CASCaM) University of North Texas Denton TX 76203 USA
| | - Timothy H. Warren
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
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42
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Bakhoda A(G, Jiang Q, Badiei YM, Bertke JA, Cundari TR, Warren TH. Copper‐Catalyzed C(sp
3
)−H Amidation: Sterically Driven Primary and Secondary C−H Site‐Selectivity. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201810556] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
| | - Quan Jiang
- Department of Chemistry Center for Advanced Scientific Computing and Modeling (CASCaM) University of North Texas Denton TX 76203 USA
| | - Yosra M. Badiei
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | - Jeffery A. Bertke
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
| | - Thomas R. Cundari
- Department of Chemistry Center for Advanced Scientific Computing and Modeling (CASCaM) University of North Texas Denton TX 76203 USA
| | - Timothy H. Warren
- Department of Chemistry Georgetown University Box 571227 Washington DC 20057-1227 USA
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43
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Kundu S, Phu PN, Ghosh P, Kozimor SA, Bertke JA, Stieber SCE, Warren TH. Nitrosyl Linkage Isomers: NO Coupling to N 2O at a Mononuclear Site. J Am Chem Soc 2019; 141:1415-1419. [PMID: 30599509 DOI: 10.1021/jacs.8b09769] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Linkage isomers of reduced metal-nitrosyl complexes serve as key species in nitric oxide (NO) reduction at monometallic sites to produce nitrous oxide (N2O), a potent greenhouse gas. While factors leading to extremely rare side-on nitrosyls are unclear, we describe a pair of nickel-nitrosyl linkage isomers through controlled tuning of noncovalent interactions between the nitrosyl ligands and differently encapsulated potassium cations. Furthermore, these reduced metal-nitrosyl species with N-centered spin density undergo radical coupling with free NO and provide a N-N coupled cis-hyponitrite intermediate whose protonation triggers the release of N2O. This report outlines a stepwise molecular mechanism of NO reduction to form N2O at a mononuclear metal site that provides insight into the related biological reduction of NO to N2O.
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Affiliation(s)
- Subrata Kundu
- Department of Chemistry , Georgetown University , Box 571227-1227, Washington , D. C. 20057 , United States.,School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram , Kerala 695551 , India
| | - Phan N Phu
- California State Polytechnic University , Pomona , California 91768 , United States
| | - Pokhraj Ghosh
- Department of Chemistry , Georgetown University , Box 571227-1227, Washington , D. C. 20057 , United States
| | - Stosh A Kozimor
- Los Alamos National Laboratory , MS K558, Los Alamos , New Mexico 87545 , United States
| | - Jeffery A Bertke
- Department of Chemistry , Georgetown University , Box 571227-1227, Washington , D. C. 20057 , United States
| | - S Chantal E Stieber
- California State Polytechnic University , Pomona , California 91768 , United States.,Los Alamos National Laboratory , MS K558, Los Alamos , New Mexico 87545 , United States
| | - Timothy H Warren
- Department of Chemistry , Georgetown University , Box 571227-1227, Washington , D. C. 20057 , United States
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Adcock AK, Gibbons B, Einkauf JD, Bertke JA, Rubinson JF, de Lill DT, Knope KE. Bismuth(iii)-thiophenedicarboxylates as host frameworks for lanthanide ions: synthesis, structural characterization, and photoluminescent behavior. Dalton Trans 2018; 47:13419-13433. [PMID: 30183020 DOI: 10.1039/c8dt02920b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Three bismuth-2,5-thiophenedicarboxylates (Bi-TDC) and two europium-2,5-thiophenedicarboxylates (Eu-TDC) were synthesized under ambient conditions. The structures were determined through single crystal X-ray diffraction, and three of the phases were further characterized by powder X-ray diffraction, Raman spectroscopy, and thermogravimetric analysis. Reactions of bismuth nitrate, 2,5-thiophenedicarboxylate, and pyridine in an acidic solution of acetic acid and ethanol yield Hpy[Bi(TDC)2(H2O)]·1.5H2O (1), whereas reactions in a water/ethanol mixture produce a minor phase, [Hpy]3[Bi2(TDC)4(HTDC)(H2O)]·xH2O (2) along with a major product, (Hpy)2[Bi(TDC)2(HTDC)]·0.36H2O (3). The structures of 1-3 are all built from anionic Bi-TDC chains that are further bridged through additional TDC linkages into interpenetrated 2D sheets. Addition of an aqueous lanthanide solution to the reaction mixtures that yielded 1 and 2-3 resulted in the formation of doped phases, Hpy[Bi1-xLnx(TDC)2(H2O)]·1.5H2O (Bi1-xLnx-1), where Ln = Nd, Sm, Eu, Tb, Dy, and Yb, and (Hpy)2[Bi0.99Eu0.01 (TDC)2(HTDC)]·0.36H2O (Bi0.99Eu0.01-3). Using europium nitrate rather than the bismuth precursor resulted in the formation of two homometallic europium based phases, [Eu(TDC)(NO3)(H2O)]n (4) and [Eu2(TDC)3(H2O)9]·5H2O (5), which adopt an extended 3D network and an interpenetrated 2D structure, respectively. Photophysical measurements were carried out for 1 and the lanthanide containing phases and quantum yield and lifetime values were determined for the visible light emitters. Herein, the structural chemistry, spectroscopic properties, and luminescence of the bismuth phases, their lanthanide doped analogs, and the europium compounds are presented.
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Affiliation(s)
- Alyssa K Adcock
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington DC 20057, USA.
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45
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Vanagas NA, Wacker JN, Rom CL, Glass EN, Colliard I, Qiao Y, Bertke JA, Van Keuren E, Schelter EJ, Nyman M, Knope KE. Solution and Solid State Structural Chemistry of Th(IV) and U(IV) 4-Hydroxybenzoates. Inorg Chem 2018; 57:7259-7269. [DOI: 10.1021/acs.inorgchem.8b00919] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nicole A. Vanagas
- Department of Chemistry, Georgetown University, 37th and O Streets Northwest, Washington, D.C. 20057, United States
| | - Jennifer N. Wacker
- Department of Chemistry, Georgetown University, 37th and O Streets Northwest, Washington, D.C. 20057, United States
| | - Christopher L. Rom
- Department of Chemistry, Georgetown University, 37th and O Streets Northwest, Washington, D.C. 20057, United States
| | - Elliot N. Glass
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Ian Colliard
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Yusen Qiao
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, 37th and O Streets Northwest, Washington, D.C. 20057, United States
| | - Edward Van Keuren
- Department of Physics, Georgetown University, 37th and O Streets Northwest, Washington, D.C. 20057, United States
| | - Eric J. Schelter
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - May Nyman
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Karah E. Knope
- Department of Chemistry, Georgetown University, 37th and O Streets Northwest, Washington, D.C. 20057, United States
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46
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Batrice RJ, Ayscue RL, Adcock AK, Sullivan BR, Han SY, Piccoli PM, Bertke JA, Knope KE. Photoluminescence of Visible and NIR-Emitting Lanthanide-Doped Bismuth-Organic Materials. Chemistry 2018; 24:5630-5636. [PMID: 29359514 DOI: 10.1002/chem.201706143] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Indexed: 12/28/2022]
Abstract
A bismuth-organic compound containing 2,2':6'2"-terpyridine (terpy) and 2-thiophenecarboxylate (TC), of the general formula (terpy)Bi(κ2 -TC)3 ⋅0.47 H2 O (BiOM-1), has been synthesized under hydrothermal conditions. Addition of a lanthanide nitrate solution to the reaction mixture led to statistical replacement of the bismuth centers, and yielded isomorphous lanthanide containing compounds Bi1-x Lnx OM-1 (Ln=Nd, Sm, Eu, Tb, Dy, Er, and Yb) that showed bismuth and/or ligand sensitized lanthanide-centered emission, and the first example of NIR emission from a lanthanide doped BiOM. The structure was determined by single-crystal X-ray diffraction, and the level and uniformity of lanthanide ion incorporation into the bismuth host was determined by ICP-OES and electron microprobe analysis. For the visible emitters, lifetime data and quantum yields are presented. A high efficiency of sensitization was calculated for the europium analog (50.1 %), showing significant improvement over previously reported europium thiophenecarboxylates. These novel materials may provide strategies to address concerns over the long-term sustainability of the rare earth elements, especially relating to optical devices.
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Affiliation(s)
- Rami J Batrice
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
| | - R Lee Ayscue
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
| | - Alyssa K Adcock
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
| | - Benjamin R Sullivan
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
| | - Sae Young Han
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
| | - Philip M Piccoli
- Department of Geology, University of Maryland, College Park, MD, 20742, USA
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
| | - Karah E Knope
- Department of Chemistry, Georgetown University, 37th and O Sts. NW, Washington, DC, 20057, USA
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47
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Abstract
The rearrangement of a diphenylurea to a more stable quinazolinone is confirmed through X-ray diffraction and DFT calculations.
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48
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Solomos MA, Bertke JA, Swift JA. Crystal structure of a diaryl carbonate: 1,3-phenylene bis(phenyl carbonate). Acta Crystallogr E Crystallogr Commun 2017; 73:1942-1945. [PMID: 29250420 PMCID: PMC5730257 DOI: 10.1107/s2056989017016772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 11/21/2017] [Indexed: 12/02/2022]
Abstract
The whole molecule of the title diarylcarbonate is generated by mirror symmetry, the mirror bisecting the central benzene ring, and the carbonate groups adopt an s-cis-s-cis conformation. In the crystal, there are only weak C—H⋯O hydrogen bonds and offset π–π interactions present. The whole molecule of the title compound, C20H14O6, is generated by mirror symmetry, the mirror bisecting the central benzene ring. The carbonate groups adopt an s-cis-s-cis conformation, with torsion angles of 58.7 (2) and 116.32 (15)°. The crystal structure of 1,3-phenylene bis(phenyl carbonate) contains no strong hydrogen bonds, though weak C—H⋯O and offset π–π interactions are observed, forming layers parallel to the ac plane.
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Hall VM, Bertke JA, Swift JA. A new polymorph of 2,6-diaminopyridine. Acta Crystallogr C Struct Chem 2017; 73:990-993. [PMID: 29111531 DOI: 10.1107/s2053229617014978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/16/2017] [Indexed: 11/10/2022]
Abstract
2,6-Diaminopyridine (26-DAP, C5H7N3) is a common intermediate in the synthesis of aromatic azo chromophores, which are widespread in the dyes and pigments industry. Sublimation of commercial 26-DAP powder yielded a new polymorph, denoted Form II, which grew as colorless orthorhombic needles. Recrystallization from acetone or toluene also yielded Form II as the major phase. Thermal analysis shows that Form II is a less stable polymorph and it converts upon heating at 335 K to the previously reported Form I.
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Affiliation(s)
- Victoria M Hall
- Department of Chemistry, Georgetown University, 37th and O Sts NW, Washington, DC 20057, USA
| | - Jeffery A Bertke
- Department of Chemistry, Georgetown University, 37th and O Sts NW, Washington, DC 20057, USA
| | - Jennifer A Swift
- Department of Chemistry, Georgetown University, 37th and O Sts NW, Washington, DC 20057, USA
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50
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Yin X, Shi M, Wu J, Pan YT, Gray DL, Bertke JA, Yang H. Quantitative Analysis of Different Formation Modes of Platinum Nanocrystals Controlled by Ligand Chemistry. Nano Lett 2017; 17:6146-6150. [PMID: 28873317 DOI: 10.1021/acs.nanolett.7b02751] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Well-defined metal nanocrystals play important roles in various fields, such as catalysis, medicine, and nanotechnology. They are often synthesized through kinetically controlled process in colloidal systems that contain metal precursors and surfactant molecules. The chemical functionality of surfactants as coordinating ligands to metal ions however remains a largely unsolved problem in this process. Understanding the metal-ligand complexation and its effect on formation kinetics at the molecular level is challenging but essential to the synthesis design of colloidal nanocrystals. Herein we report that spontaneous ligand replacement and anion exchange control the form of coordinated Pt-ligand intermediates in the system of platinum acetylacetonate [Pt(acac)2], primary aliphatic amine, and carboxylic acid ligands. The formed intermediates govern the formation mode of Pt nanocrystals, leading to either a pseudo two-step or a one-step mechanism by switching on or off an autocatalytic surface growth. This finding shows the importance of metal-ligand complexation at the prenucleation stage and represents a critical step forward for the designed synthesis of nanocrystal-based materials.
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Affiliation(s)
- Xi Yin
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign , 206 Roger Adams Laboratory, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Miao Shi
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign , 206 Roger Adams Laboratory, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Jianbo Wu
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign , 206 Roger Adams Laboratory, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Yung-Tin Pan
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign , 206 Roger Adams Laboratory, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Danielle L Gray
- George L. Clark X-ray Facility, University of Illinois at Urbana-Champaign , 505 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Jeffery A Bertke
- George L. Clark X-ray Facility, University of Illinois at Urbana-Champaign , 505 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Hong Yang
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign , 206 Roger Adams Laboratory, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
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