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Wang S, Huang Q. A spectroscopic approach to identifying the out-of-plane conformations of Ni(II) meso-tetraphenylporphyrin in solution. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2
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Latypov SK, Kondrashova SA, Polyancev FM, Sinyashin OG. Quantum Chemical Calculations of 31P NMR Chemical Shifts in Nickel Complexes: Scope and Limitations. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Shamil K. Latypov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov str. 8, Kazan, Tatarstan, Russian Federation 420083
| | - Svetlana A. Kondrashova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov str. 8, Kazan, Tatarstan, Russian Federation 420083
| | - Fedor M. Polyancev
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov str. 8, Kazan, Tatarstan, Russian Federation 420083
| | - Oleg G. Sinyashin
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov str. 8, Kazan, Tatarstan, Russian Federation 420083
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Atoyebi AO, Brückner C. Observations on the Mechanochemical Insertion of Zinc(II), Copper(II), Magnesium(II), and Select Other Metal(II) Ions into Porphyrins. Inorg Chem 2019; 58:9631-9642. [DOI: 10.1021/acs.inorgchem.9b00052] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Adewole O. Atoyebi
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
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Apaydin DH, Portenkirchner E, Jintanalert P, Strauss M, Luangchaiyaporn J, Sariciftci NS, Thamyongkit P. Synthesis and investigation of tetraphenyltetrabenzoporphyrins for electrocatalytic reduction of carbon dioxide. SUSTAINABLE ENERGY & FUELS 2018; 2:2747-2753. [PMID: 31497650 PMCID: PMC6695572 DOI: 10.1039/c8se00422f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 10/04/2018] [Indexed: 06/10/2023]
Abstract
We report the synthesis and electrochemical properties of freebase tetraphenyltetrabenzoporphyrin and its complexes of Zn(ii), Co(ii), Ni(ii), Cu(ii) and Sn(iv) towards electrochemical reduction of carbon dioxide (CO2). Based on cyclic voltammetry, it is shown that central metals significantly affect the electrocatalytic performance in the reduction of CO2 in terms of reduction potential and catalytic current enhancement. At an applied potential of -1.90 V vs. an Ag/AgCl quasi reference electrode for 20 h, the electrocatalytic reduction of CO2 realized by Zn(ii)- and Cu(ii)-tetraphenyltetrabenzoporphyrins to carbon monoxide resulted in faradaic efficiencies of around 48% and 33%, respectively.
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Affiliation(s)
- Dogukan H Apaydin
- Linz Institute for Organic Solar Cells (LIOS) , Institute of Physical Chemistry , Johannes Kepler University Linz , 4040 Linz , Austria . ;
| | | | - Pichayada Jintanalert
- Department of Chemistry , Faculty of Science , Chulalongkorn University , 10330 Bangkok , Thailand
| | - Matthias Strauss
- Linz Institute for Organic Solar Cells (LIOS) , Institute of Physical Chemistry , Johannes Kepler University Linz , 4040 Linz , Austria . ;
| | - Jirapong Luangchaiyaporn
- Department of Chemistry , Faculty of Science , Chulalongkorn University , 10330 Bangkok , Thailand
| | - Niyazi Serdar Sariciftci
- Linz Institute for Organic Solar Cells (LIOS) , Institute of Physical Chemistry , Johannes Kepler University Linz , 4040 Linz , Austria . ;
| | - Patchanita Thamyongkit
- Research Group on Materials for Clean Energy Production STAR , Department of Chemistry , Faculty of Science , Chulalongkorn University , 10330 Bangkok , Thailand
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5
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Leben L, Schaub E, Näther C, Herges R. Crystal structure of (diethyl ether-κ O)[5,10,15,20-tetra-kis-(2-iso-thio-cyanato-phen-yl)porphyrinato-κ 4 N]zinc diethyl ether solvate. Acta Crystallogr E Crystallogr Commun 2018; 74:1609-1612. [PMID: 30443391 PMCID: PMC6218912 DOI: 10.1107/s2056989018014238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 10/08/2018] [Indexed: 12/03/2022]
Abstract
The crystal structure of the title compound, [Zn(C48H24N8S4)(C4H10O)]·C4H10O, consists of discrete porphyrin complexes that are located on a twofold rotation axis. The ZnII cation is fivefold coordinated by four N atoms of the porphyrin moiety and one O atom of a diethyl ether mol-ecule in a slightly distorted square-pyramidal environment with the diethyl ether mol-ecule in the apical position. The porphyrin backbone is nearly planar with the metal cation slightly shifted out of the plane towards the coordinating diethyl ether mol-ecule. All four iso-thio-cyanato groups of the phenyl substituents at the meso-positions face the same side of the porphyrin, as is characteristic for picket fence porphyrins. In the crystal structure, the discrete porphyrin complexes are arranged in such a way that cavities are formed in which additional diethyl ether solvate mol-ecules are located around a twofold rotation axis. The O atom of the solvent mol-ecule is not positioned exactly on the twofold rotation axis, thus making the whole mol-ecule equally disordered over two symmetry-related positions.
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Affiliation(s)
- Lisa Leben
- Institut für Organische Chemie, Universität Kiel, Otto-Hahn-Platz 4, 24118, Kiel, Germany
| | - Eike Schaub
- Institut für Organische Chemie, Universität Kiel, Otto-Hahn-Platz 4, 24118, Kiel, Germany
| | - Christian Näther
- Institut für Anorganische Chemie, Universität Kiel, Otto-Hahn-Platz 6/7, 24118, Kiel, Germany
| | - Rainer Herges
- Institut für Organische Chemie, Universität Kiel, Otto-Hahn-Platz 4, 24118, Kiel, Germany
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6
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Qian W, González-Campo A, Pérez-Rodríguez A, Rodríguez-Hermida S, Imaz I, Wurst K, Maspoch D, Ruiz E, Ocal C, Barrena E, Amabilino DB, Aliaga-Alcalde N. Boosting Self-Assembly Diversity in the Solid-State by Chiral/Non-Chiral Zn II -Porphyrin Crystallization. Chemistry 2018; 24:12950-12960. [PMID: 29893444 DOI: 10.1002/chem.201802031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 06/05/2018] [Indexed: 01/11/2023]
Abstract
A chiral ZnII porphyrin derivative 1 and its achiral analogue 2 were studied in the solid state. Considering the rich molecular recognition of designed metalloporphyrins 1 and 2 and their tendency to crystallize, they were recrystallized from two solvent mixtures (CH2 Cl2 /CH3 OH and CH2 Cl2 /hexane). As a result, four different crystalline arrangements (1 a,b and 2 a,b, from 0D to 2D) were obtained. Solid-state studies were performed on all the species to analyze the role played by chirality, solvent mixtures, and surfaces (mica and HOPG) in the supramolecular arrangements. By means of combinations of solvents and substrates a variety of microsized species was obtained, from vesicles to flower-shaped arrays, including geometrical microcrystals. Overall, the results emphasize the environmental susceptibility of metalloporphyrins and how this feature must be taken into account in their design.
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Affiliation(s)
- Wenjie Qian
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari, 08193, Bellaterra, Spain
| | - Arántzazu González-Campo
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari, 08193, Bellaterra, Spain
| | - Ana Pérez-Rodríguez
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari, 08193, Bellaterra, Spain
| | - Sabina Rodríguez-Hermida
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193, Barcelona, Spain
| | - Inhaz Imaz
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193, Barcelona, Spain
| | - Klaus Wurst
- Institut für Allgemeine Anorganische und Theoretische Chemie, Universität Innsbruck, Innrain 52a, 6020, Innsbruck, Austria
| | - Daniel Maspoch
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193, Barcelona, Spain.,ICREA (Institució Catalana de Recerca i Estudis Avançats), Passeig Lluís Companys 23, 08010, Barcelona, Spain
| | - Eliseo Ruiz
- Departament de Química Inorgànica i Orgànica, Universitat de Barcelona, 08007, Barcelona, Spain.,Institut de Química Teórica i Computacional, de la Universitat de Barcelona (IQTCUB), 08007, Barcelona, Spain
| | - Carmen Ocal
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari, 08193, Bellaterra, Spain
| | - Esther Barrena
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari, 08193, Bellaterra, Spain
| | - David B Amabilino
- School of Chemistry, The University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom
| | - Núria Aliaga-Alcalde
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari, 08193, Bellaterra, Spain.,ICREA (Institució Catalana de Recerca i Estudis Avançats), Passeig Lluís Companys 23, 08010, Barcelona, Spain
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7
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Wang Y, Xue Z, Dong Y, Zhu W. Synthesis and electrochemistry of meso-substitutes dipyrromethene nickel (II) complexes. Polyhedron 2015. [DOI: 10.1016/j.poly.2015.10.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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8
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Ganapathy S, Oostergetel GT, Reus M, Tsukatani Y, Gomez Maqueo Chew A, Buda F, Bryant DA, Holzwarth AR, de Groot HJM. Structural variability in wild-type and bchQ bchR mutant chlorosomes of the green sulfur bacterium Chlorobaculum tepidum. Biochemistry 2012; 51:4488-98. [PMID: 22577986 DOI: 10.1021/bi201817x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The self-aggregated state of bacteriochlorophyll (BChl) c molecules in chlorosomes belonging to a bchQ bchR mutant of the green sulfur bacteria Chlorobaculum tepidum, which mostly produces a single 17(2)-farnesyl-(R)-[8-ethyl,12-methyl]BChl c homologue, was characterized by solid-state nuclear magnetic resonance (NMR) spectroscopy and high-resolution electron microscopy. A nearly complete (1)H and (13)C chemical shift assignment was obtained from well-resolved homonuclear (13)C-(13)C and heteronuclear (1)H-(13)C NMR data sets collected from (13)C-enriched chlorosome preparations. Pronounced doubling (1:1) of specific (13)C and (1)H resonances revealed the presence of two distinct and nonequivalent BChl c components, attributed to all syn- and all anti-coordinated parallel stacks, depending on the rotation of the macrocycle with respect to the 3(1)-methyl group. Steric hindrance from the 20-methyl functionality induces structural differences between the syn and anti forms. A weak but significant and reproducible reflection at 1/0.69 nm(-1) in the direction perpendicular to the curvature of cylindrical segments observed with electron microscopy also suggests parallel stacking of BChl c molecules, though the observed lamellar spacing of 2.4 nm suggests weaker packing than for wild-type chlorosomes. We propose that relaxation of the pseudosymmetry observed for the wild type and a related BChl d mutant leads to extended domains of alternating syn and anti stacks in the bchQ bchR chlorosomes. Domains can be joined to form cylinders by helical syn-anti transition trajectories. The phase separation in domains on the cylindrical surface represents a basic mechanism for establishing suprastructural heterogeneity in an otherwise uniform supramolecular scaffolding framework that is well-ordered at the molecular level.
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Affiliation(s)
- Swapna Ganapathy
- Leiden Institute of Chemistry, Leiden University, 2300 RA Leiden, The Netherlands
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9
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SANDERS LORIK, ARNOLD WILLIAMD, OLDFIELD ERIC. NMR, IR, Mössbauer and quantum chemical investigations of metalloporphyrins and metalloproteins. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1002/jpp.319] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We review contributions made towards the elucidation of CO and O2binding geometries in respiratory proteins. Nuclear magnetic resonance, infrared spectroscopy, Mössbauer spectroscopy, X-ray crystallography and quantum chemistry have all been used to investigate the Fe –ligand interactions. Early experimental results showed linear correlations between17O chemical shifts and the infrared stretching frequency (νCO) of the CO ligand in carbonmonoxyheme proteins and between the17O chemical shift and the13CO shift. These correlations led to early theoretical investigations of the vibrational frequency of carbon monoxide and of the13C and17O NMR chemical shifts in the presence of uniform and non-uniform electric fields. Early success in modeling these spectroscopic observables then led to the use of computational methods, in conjunction with experiment, to evaluate ligand-binding geometries in heme proteins. Density functional theory results are described which predict57Fe chemical shifts and Mössbauer electric field gradient tensors,17O NMR isotropic chemical shifts, chemical shift tensors and nuclear quadrupole coupling constants (e2qQ/h) as well as13C isotropic chemical shifts and chemical shift tensors in organometallic clusters, heme model metalloporphyrins and in metalloproteins. A principal result is that CO in most heme proteins has an essentially linear and untilted geometry (τ = 4 °, β = 7 °) which is in extremely good agreement with a recently published X-ray synchrotron structure. CO / O2discrimination is thus attributable to polar interactions with the distal histidine residue, rather than major Fe–C–O geometric distortions.
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Affiliation(s)
- LORI K. SANDERS
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - WILLIAM D. ARNOLD
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - ERIC OLDFIELD
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
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10
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Maiti M, Danger BR, Steer RP. Photophysics of Soret-Excited Tetrapyrroles in Solution. IV. Radiationless Decay and Triplet−Triplet Annihilation Investigated Using Tetraphenylporphinato Sn(IV). J Phys Chem A 2009; 113:11318-26. [DOI: 10.1021/jp906966h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manisankar Maiti
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, SK S7N 5C9, Canada
| | - Brook R. Danger
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, SK S7N 5C9, Canada
| | - Ronald P. Steer
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, SK S7N 5C9, Canada
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Pazderski L, Tousek J, Sitkowski J, Kozerski L, Szłyk E. Experimental and quantum-chemical studies of 1H, 13C and 15N NMR coordination shifts in Pd(II) and Pt(II) chloride complexes with quinoline, isoquinoline, and 2,2'-biquinoline. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45:1059-1071. [PMID: 18044805 DOI: 10.1002/mrc.2105] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
1H, 13C, and 15N NMR studies of platinide(II) (M=Pd, Pt) chloride complexes with quinolines (L=quinoline-quin, or isoquinoline-isoquin; LL=2,2'-biquinoline-bquin), having the general formulae trans-/cis-[ML2Cl2] and [M(LL)Cl2], were performed and the respective chemical shifts (delta1H, delta13C, delta15N) reported. 1H coordination shifts of various signs and magnitudes (Delta1Hcoord=delta1Hcomplex-delta1Hligand) are discussed in relation to the changes of diamagnetic contribution to the relevant 1H shielding constants. The comparison to the literature data for similar complexes containing auxiliary ligands other than chlorides exhibited a large dependence of delta1H parameters on electron density variations and ring-current effects (inductive and anisotropic phenomena). The influence of deviations from planarity, concerning either MN2Cl2 chromophores or azine ring systems, revealed by the known X-ray structures of [Pd(bquin)Cl2] and [Pt(bquin)Cl2], is discussed in respect to 1H NMR spectra. 15N coordination shifts (Delta15Ncoord=delta15Ncomplex-delta15Nligand) of ca. 78-100 ppm (to lower frequency) are attributed mainly to the decrease of the absolute value of paramagnetic contribution in the relevant 15N shielding constants, this phenomenon being noticeably dependent on the type of a platinide metal and coordination sphere geometry. The absolute magnitude of Delta15Ncoord parameter increased by ca 15 ppm upon Pd(II)-->Pt(II) replacement but decreased by ca. 15 ppm following trans-->cis transition. Experimental 1H, 13C, 15N NMR chemical shifts are compared to those quantum-chemically calculated by B3LYP/LanL2DZ+6-31G**//B3LYP/LanL2DZ+6-31G*, both in vacuo and in CHCl3 or DMF solution.
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Affiliation(s)
- Leszek Pazderski
- Faculty of Chemistry, Nicholas Copernicus University, Gagarina 7, PL-87100, Toruń, Poland.
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Pazderski L, Tousek J, Sitkowski J, Kozerski L, Szłyk E. Experimental and quantum-chemical studies of 1H, 13C and 15N NMR coordination shifts in Pd(II) and Pt(II) chloride complexes with methyl and phenyl derivatives of 2,2'-bipyridine and 1,10-phenanthroline. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45:1045-1058. [PMID: 18044804 DOI: 10.1002/mrc.2104] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
1H, 13C and 15N NMR studies of platinide(II) (M=Pd, Pt) chloride complexes with methyl and phenyl derivatives of 2,2'-bipyridine and 1,10-phenanthroline [LL=4,4'-dimethyl-2,2'-bipyridine (dmbpy); 4,4'-diphenyl-2,2'-bipyridine (dpbpy); 4,7-dimethyl-1,10-phenanthroline (dmphen); 4,7-diphenyl-1,10-phenanthroline (dpphen)] having a general [M(LL)Cl2] formula were performed and the respective chemical shifts (delta1H, delta13C, delta15N) reported. 1H high-frequency coordination shifts (Delta1Hcoord=delta1Hcomplex-delta1Hligand) were discussed in relation to the changes of diamagnetic contribution in the relevant 1H shielding constants. The comparison to literature data for similar [M(LL)(XX)], [M(LL)X2] and [M(LL)XY] coordination or organometallic compounds containing various auxiliary ligands revealed a large dependence of delta1H parameters on inductive and anisotropic effects. 15N low-frequency coordination shifts (Delta15Ncoord=delta 15Ncomplex-delta15Nligand) of ca 88-96 ppm for M=Pd and ca 103-111 ppm for M=Pt were attributed to both the decrease of the absolute value of paramagnetic contribution and the increase of the diamagnetic term in the expression for 15N shielding constants. The absolute magnitude of Delta15Ncoord parameter increased by ca 15 ppm upon Pd(II)-->Pt(II) transition and by ca 6-7 ppm following dmbpy-->dmphen or dpbpy-->dpphen ligand replacement; variations between analogous complexes containing methyl and phenyl ligands (dmbpy vs dpbpy; dmphen vs dpphen) did not exceed+/-1.5 ppm. Experimental 1H, 13C, 15N NMR chemical shifts were compared to those quantum-chemically calculated by B3LYP/LanL2DZ+6-31G**//B3LYP/LanL2DZ+6-31G*, both in vacuo and in DMSO or DMF solution.
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Affiliation(s)
- Leszek Pazderski
- Faculty of Chemistry, Nicholas Copernicus University, Gagarina 7, PL-87100 Toruń, Poland.
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Penner GH, McCullough A. Solid-State Nitrogen-15 NMR and Quantum Chemical Study of N, N-Dimethylaniline Derivatives. J Org Chem 2006; 71:8794-9. [PMID: 17081008 DOI: 10.1021/jo061491u] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study the components of the nitrogen chemical shift (CS) tensor are examined for a series of para substituted N,N-dimethylaniline derivatives. This is done through measurement of the 15N NMR spectra of powder samples and through quantum chemical calculations on the isolated molecules. Experiments and calculations show that the isotropic CS, delta(iso), decreases with increasing electron donating ability of the para substituent, in agreement with previous solution studies. More importantly, this study shows that this decrease in the isotropic (solution) CS is due to decreasing values of the CS tensor component delta(11) and component delta(33). The component delta(22) is essentially invariant to the electron donating/withdrawing ability of the para substituent. Through Ramsey's theory of nuclear magnetic shielding, it can be seen that the variation in delta(11) and delta(33), and hence delta(iso), is due to changes in the n-pi* and the sigma-pi* energy gaps in N,N-dimethylaniline. This, in turn, is a result of the change in the energy of the pi* molecular orbital with change in the pi-electron donating ability of the para substituent. The effects of nitrogen inversion on the components of the nitrogen CS tensor components are also discussed. This study also shows the feasibility of performing 15N cross-polarization experiments on nonspinning powder samples at natural isotopic abundance.
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Affiliation(s)
- Glenn H Penner
- Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
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Nardis S, Paolesse R, Licoccia S, Fronczek FR, Vicente MGH, Shokhireva TK, Cai S, Walker FA. NMR and structural investigations of a nonplanar iron corrolate: modified patterns of spin delocalization and coupling in a slightly saddled chloroiron(III) corrolate radical. Inorg Chem 2006; 44:7030-46. [PMID: 16180865 DOI: 10.1021/ic0504846] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An undecasubstituted chloroiron corrolate, octamethyltriphenylcorrolatoiron chloride, (OMTPCorr)FeCl, has been synthesized and studied by X-ray crystallography and (1)H and (13)C NMR spectroscopy. It is found that, although the structure is slightly saddled, the average methyl out-of-plane distance is only 0.63 Angstroms, while it is much greater for the dodecasubstituted porphyrinate analogue (OMTPP)FeCl (1.19 Angstroms) (Cheng, R.-J.; Chen, P.-Y.; Gau, P.-R.; Chen, C.-C.; Peng, S.-M. J. Am. Chem. Soc. 1997, 119, 2563-2569). In addition, the distance of iron from the mean plane of the four macrocycle nitrogens is also smaller for (OMTPCorr)FeCl (0.387 Angstroms) than for (OMTPP)FeCl (0.46 Angstroms). The (1)H and (13)C NMR spectra of (OMTPCorr)FeCl, as well as the chloroiron complexes of triphenylcorrolate, (TPCorr)FeCl; 7,13-dimethyl-2,3,8,12,17,18-hexaethylcorrolate, (DMHECorr)FeCl; 7,8,12,13-tetramethyl-2,3,17,18-tetraethylcorrolate, (TMTECorr)FeCl; and the phenyliron complex of 7,13-dimethyl-2,3,8,12,17,18-hexaethylcorrolate, (DMHECorr)FePh, have been assigned, and the spin densities at the carbons that are part of the aromatic ring of the corrole macrocycle have been divided into the part due to spin delocalization by corrole --> Fe pi donation and the part due to the unpaired electron present on the corrole ring. It is found that although the spin density at the beta-pyrrole positions is fairly similar to that of (TPCorr)FeCl, the meso-phenyl-carbon shift differences delta(m) - delta(p) are opposite in sign of those of (TPCorr)FeCl. This finding suggests that the radical electron is ferromagnetically coupled to the unpaired electrons on iron, rather than antiferromagnetically coupled, as in all of the other chloroiron corrolates. The solution magnetic moment was measured for (OMTPCorr)FeCl and found to be mu(eff) = 4.7 +/- 0.5 micro(B), consistent with S = 2 and ferromagnetic coupling. From this study, two conclusions may be reached about iron corrolates: (1) the spin states of chloroiron corrolates are extremely sensitive to the out-of-plane distance of iron, and (2) pyrrole-H or -C shifts are not useful in delineating the spin state and electron configuration of (anion)iron corrolates.
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Affiliation(s)
- Sara Nardis
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Italy
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Marchetti F, Pettinari C, Pettinari R, Cingolani A, Gobetto R, Chierotti MR, Drozdov A, Troyanov SI. The Imidazole Role in Strontium β-Diketonate Complexes Formation. Inorg Chem 2006; 45:3074-85. [PMID: 16562964 DOI: 10.1021/ic051972g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A selection of new strontium beta-diketonate derivatives (imH2)2[Sr2(beta-dike)6] [where imH = imidazole and beta-dike = tfac (tfacH = 1,1,1-trifluoro-2,4-pentanedione), tfbz (tfbzH = 1,1,1-trifluoro-4-phenyl-2,4-butanedione), or hfac (hfacH = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione)], [Sr2(tfac)4(Meim)2(H2O)2], (MeimH)2[Sr(beta-dike)4] (where Meim = 1-methylimidazole and beta-dike = tfbz or hfac), [Sr2(thd)4(imH)2(EtOH)], and [Sr2(thd)4(Meim)2(EtOH)] (where thdH = 2,2,6,6-tetramethyl-3,5-heptanedione) have been synthesized and fully characterized. (imH2)2[Sr2(beta-dike)6] and (MeimH)2[Sr(beta-dike)4] are di- and mononuclear Sr anionic complexes, respectively, while [Sr2(tfac)4(Meim)2(H2O)2], [Sr2(thd)4(imH)2(EtOH)], and [Sr2(thd)4(Meim)2(EtOH)] are neutral dinuclear molecular derivatives. The derivative (imH2)2[Sr2(hfac)6] slowly decomposes in solution under aerobic conditions, giving (imH2)2[Sr(H2O)2(tfa)3](tfa) (tfaH = trifluoroacetic acid), which is an ionic compound containing polynuclear anionic chains composed of Sr(H2O)2(tfa)3 units. When a deficiency of imH is employed, the thdH proligand forms not only the dinuclear derivative [Sr2(thd)4(imH)2(EtOH)] but also an additional product with the formula [Sr(thd)2(H2O)2(EtOH)], in which the Sr atom is seven-coordinated. A complete solid-state characterization has been accomplished by comparing X-ray and solid-state 13C NMR data. Elucidation of the H-bond interaction between the heterocyclic rings and metal complexes by cross-polarization magic-angle-spinning 15N NMR is also reported.
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Affiliation(s)
- Fabio Marchetti
- Dipartimento di Scienze Chimiche, Università degli Studi, via S. Agostino 1, 62032 Camerino, Italy.
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Pazderski L, Szłyk E, Sitkowski J, Kamieński B, Kozerski L, Tousek J, Marek R. Experimental and quantum-chemical studies of 15N NMR coordination shifts in palladium and platinum chloride complexes with pyridine, 2,2'-bipyridine and 1,10-phenanthroline. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2006; 44:163-70. [PMID: 16392105 DOI: 10.1002/mrc.1740] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A series of Pd and Pt chloride complexes with pyridine (py), 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen), of general formulae trans-/cis-[M(py)2Cl2], [M(py)4]Cl2, trans-/cis-[M(py)2Cl4], [M(bpy)Cl2], [M(bpy)Cl4], [M(phen)Cl2], [M(phen)Cl4], where M = Pd, Pt, was studied by 1H, 195Pt, and 15N NMR. The 90-140 ppm low-frequency 15N coordination shifts are discussed in terms of such structural features of the complexes as the type of platinide metal, oxidation state, coordination sphere geometry and the type of ligand. The results of quantum-chemical NMR calculations were compared with the experimental 15N coordination shifts, well reproducing their magnitude and correlation with the molecular structure.
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Affiliation(s)
- Leszek Pazderski
- Faculty of Chemistry, Nicholas Copernicus University, Gagarina 7, PL-87100, Toruń, Poland.
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17
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Umetsu M, Hollander JG, Matysik J, Wang ZY, Adschiri T, Nozawa T, de Groot HJM. Magic-Angle Spinning Nuclear Magnetic Resonance under Ultrahigh Field Reveals Two Forms of Intermolecular Interaction within CH2Cl2-Treated (3R)-Type Bacteriochlorophyll c Solid Aggregate. J Phys Chem B 2004. [DOI: 10.1021/jp034957a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mitsuo Umetsu
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
| | - Johan G. Hollander
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
| | - Jörg Matysik
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
| | - Zheng-Yu Wang
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
| | - Tadafumi Adschiri
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
| | - Tsunenori Nozawa
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
| | - Huub J. M. de Groot
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai, 980-8577, Japan, and Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 07, Aoba-ku, Sendai 980-8579, Japan
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18
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Penner GH, Bernard GM, Wasylishen RE, Barrett A, Curtis RD. A solid-state nitrogen-15 NMR and ab initio study of nitrobenzenes. J Org Chem 2003; 68:4258-64. [PMID: 12762724 DOI: 10.1021/jo0207372] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Insight into the unexpectedly small range of isotropic nitrogen chemical shifts in nitrobenzene derivatives is gained through measurements of the chemical shift (CS) tensor by solid-state NMR experiments and ab initio molecular orbital (MO) and density functional theory (DFT) calculations. The principal components, delta(ii), of the (15)N CS tensors have been measured for nitrobenzene, 4-nitroaniline, 4-nitrotoluene, 4-nitroanisole, 4-nitroacetophenone, nitromesitylene, and 2,4,6-tri-tert-butylnitrobenzene. No obvious correlations of the delta(ii) values with traditional reactivity parameters were observed. The CS tensor components change significantly for the para-substituted nitrobenzenes, but these variations nearly cancel to yield isotropic shifts that fall in a range of only 3 ppm. Ab initio calculations of the delta(ii) values at the HF level are in poor agreement with the experimental values, whereas MP2 calculations and DFT calculations employing the B3LYP functional are in better agreement with experiment. The calculated (B3LYP/6-311G) delta(ii) values follow a trend in which delta(11) and delta(33) increase while delta(22) decreases with the accepted electron withdrawing ability of the para substituent. These changes tend to cancel yielding a variation in delta(iso) of only 4 ppm. These calculations indicate that the CS tensor has the same orientation as the carbon CS tensor in the isoelectronic benzoate anion: delta(11) bisects the O-N-O angle, delta(33) is perpendicular to the NO(2) plane, and delta(22) is in the NO(2) plane and perpendicular to delta(11).
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Affiliation(s)
- Glenn H Penner
- Department of Chemistry, University of Guelph, Ontario, Canada N1G 2W1.
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Kidambi SS, Lee DK, Ramamoorthy A. Interaction of Cd and Zn with biologically important ligands characterized using solid-state NMR and ab initio calculations. Inorg Chem 2003; 42:3142-51. [PMID: 12716214 DOI: 10.1021/ic026287d] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
For the first time, coordination geometry and structure of metal binding sites in biologically relevant systems are studied using chemical shift parameters obtained from solid-state NMR experiments and quantum chemical calculations. It is also the first extensive report looking at metal-imidazole interaction in the solid state. The principal values of the (113)Cd chemical shift anisotropy (CSA) tensor in crystalline cadmium histidinate and two different cadmium formates (hydrate and anhydrate) were experimentally measured to understand the effect of coordination number and geometry on (113)Cd CSA. Further, (13)C and (15)N chemical shifts have also been experimentally determined to examine the influence of cadmium on the chemical shifts of (15)N and (13)C nuclei present near the metal site in the cadmium-histidine complex. These values were then compared with the chemical shift values obtained from the isostructural bis(histidinato)zinc(II) complex as well as from the unbound histidine. The results show that the isotropic chemical shift values of the carboxyl carbons shift downfield and those of amino and imidazolic nitrogens shift upfield in the metal (Zn,Cd)-histidine complexes relative to the values of the unbound histidine sample. These shifts are in correspondence with the anticipated values based on the crystal structure. Ab initio calculations on the cadmium histidinate molecule show good agreement with the (113)Cd CSA tensors determined from solid-state NMR experiments on powder samples. (15)N chemical shifts for other model complexes, namely, zinc glycinate and zinc hexaimidazole chloride, are also considered to comprehend the effect of zinc binding on (15)N chemical shifts.
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Affiliation(s)
- Srikanth S Kidambi
- Department of Chemistry, Biophysics Research Division, University of Michigan, Ann Arbor, MI 48109-1055, USA
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Kidambi SS, Ramamoorthy A. Characterization of metal centers in bioinorganic complexes using ab initio calculations of 113Cd chemical shifts. Inorg Chem 2003; 42:2200-2. [PMID: 12665351 DOI: 10.1021/ic026165l] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Determination of (113)Cd chemical shift is of significant interest in NMR characterization of metal porphyrins, metal-histidine interactions, and other metal-ligand interactions in many bioinorganic complexes and metalloproteins. In this study, we present a detailed account of a number of quantum chemical investigations aimed at relating isotropic and anisotropic (113)Cd chemical shifts to the structure of several biologically relevant complexes with discrete and polymeric structures. Calculated and experimentally determined chemical shift values are compared to correlate the variation of the chemical shift values with the structural changes around the metal center. Our results infer that the density functional theory using the Sadlej basis set on the cadmium atom is a suitable method for estimating cadmium shielding values to a reasonable accuracy.
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Affiliation(s)
- Srikanth S Kidambi
- Biophysics Research Division, Department of Chemistry, and Macromolecular Science & Engineering, University of Michigan, Ann Arbor, Michigan 48109-1055, USA
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21
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Hu JZ, Solum MS, Wind RA, Nilsson BL, Peterson MA, Pugmire RJ, Grant DM. H and 15N Dynamic Nuclear Polarization Studies of Carbazole. J Phys Chem A 2000. [DOI: 10.1021/jp9938011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jian Z. Hu
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
| | - Mark S. Solum
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
| | - Robert A. Wind
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
| | - Brad L. Nilsson
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
| | - Matt A. Peterson
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
| | - Ronald J. Pugmire
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
| | - David M. Grant
- Departments of Chemistry and Chemical and Fuels Engineering, University of Utah, Salt Lake City, Utah 84112, Environmental and Molecular Sciences Laboratory, Battelle Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, Richland, Washington 99352, Department of Chemistry, Brigham Young University, Provo, Utah 84602
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22
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Schurko RW, Wasylishen RE. Nitrogen-15 NMR Study of Solid Cobaloximes Containing 15N-Labeled Pyridine and Aniline. J Phys Chem A 2000. [DOI: 10.1021/jp994254m] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Robert W. Schurko
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J3
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23
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Wang ZY, Umetsu M, Kobayashi M, Nozawa T. 13C- and 15N-NMR Studies on the Intact Bacteriochlorophyll c Dimers in Solutions. J Am Chem Soc 1999. [DOI: 10.1021/ja991050a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zheng-Yu Wang
- Contribution from the Department of Biomolecular Engineering, Faculty of Engineering, Center for Interdisciplinary Science, Tohoku University, Sendai 980-8579, Japan
| | - Mitsuo Umetsu
- Contribution from the Department of Biomolecular Engineering, Faculty of Engineering, Center for Interdisciplinary Science, Tohoku University, Sendai 980-8579, Japan
| | - Masayuki Kobayashi
- Contribution from the Department of Biomolecular Engineering, Faculty of Engineering, Center for Interdisciplinary Science, Tohoku University, Sendai 980-8579, Japan
| | - Tsunenori Nozawa
- Contribution from the Department of Biomolecular Engineering, Faculty of Engineering, Center for Interdisciplinary Science, Tohoku University, Sendai 980-8579, Japan
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24
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Hughes E, Brouwer EB, Harris RK. Fluorine-19 solid-state NMR magic-angle-turning experiments using multiple-pulse homonuclear decoupling. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1999; 138:256-267. [PMID: 10341129 DOI: 10.1006/jmre.1999.1740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
For compounds giving "crowded" 1-dimensional magic-angle-spinning spectra, information about the local atomic environment in the form of the chemical shift anisotropy (CSA) is sacrificed for high resolution of the less informative isotropic chemical shift. Magic-angle-turning (MAT) NMR pulse sequences preserve the CSA information by correlating it to the isotropic chemical shift in a 2-dimensional experiment. For low natural abundance nuclei such as 13C and 15N and under 1H heteronuclear dipolar decoupling conditions, the dominant NMR interaction is the chemical shift. For abundant nuclei such as 1H, 19F, and 31P, the homonuclear dipolar interaction becomes a significant contribution to the observed linewidth in both F1 and F2 dimensions. We incorporate MREV8 homonuclear multiple-pulse decoupling sequences into the MAT experiment to give a multiple-pulse MAT (MP-MAT) experiment in which the homonuclear dipolar interaction is suppressed while maintaining the chemical shift information. Extensive use of computer simulation using GAMMA has guided the pulse sequence development. In particular, we show how the MREV8 pulses can be incorporated into a quadrature-detected sequence such as MAT. The MP-MAT technique is demonstrated for a model two-site system containing a mixture of silver trifluoroacetate and calcium difluoride. The resolution in the isotropic evolution dimension is improved by faster sample spinning, shorter MREV8 cycle times in the evolution dimension, and modifications of the MAT component of the pulse sequence. Copyright 1999 Academic Press.
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Affiliation(s)
- E Hughes
- South Road Laboratories, University of Durham, Durham, DH1 3LE, United Kingdom
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25
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Godbout N, Sanders LK, Salzmann R, Havlin RH, Wojdelski M, Oldfield E. Solid-State NMR, Mössbauer, Crystallographic, and Density Functional Theory Investigation of Fe−O2 and Fe−O2 Analogue Metalloporphyrins and Metalloproteins. J Am Chem Soc 1999. [DOI: 10.1021/ja9832820] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nathalie Godbout
- Contribution from the Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Lori K. Sanders
- Contribution from the Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Renzo Salzmann
- Contribution from the Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Robert H. Havlin
- Contribution from the Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Mark Wojdelski
- Contribution from the Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Eric Oldfield
- Contribution from the Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
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26
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Affiliation(s)
- William P. Power
- Contribution from the Guelph-Waterloo Center for Graduate Work in Chemistry, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Christopher W. Kirby
- Contribution from the Guelph-Waterloo Center for Graduate Work in Chemistry, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Nicholas J. Taylor
- Contribution from the Guelph-Waterloo Center for Graduate Work in Chemistry, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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27
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Facelli JC. Density Functional Theory Calculations of the Structure and the 15N and 13C Chemical Shifts of Methyl Bacteriopheophorbide a and Bacteriochlorophyll a. J Phys Chem B 1998. [DOI: 10.1021/jp9800970] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Julio C. Facelli
- Center for High Performance Computing, University of Utah, Salt Lake City, Utah 84112-0190
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