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Konstantinov IA, Broadbelt LJ. Regression Formulas for Density Functional Theory Calculated 1H and 13C NMR Chemical Shifts in Toluene-d8. J Phys Chem A 2011; 115:12364-72. [DOI: 10.1021/jp2060975] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Ivan A. Konstantinov
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Rd, E-136, Evanston, Illinois 60208, United States
| | - Linda J. Broadbelt
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Rd, E-136, Evanston, Illinois 60208, United States
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52
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Jiang T, Wang L, Zhang S, Sun PC, Ding CF, Chu YQ, Zhou P. Interaction of curcumin with Al(III) and its complex structures based on experiments and theoretical calculations. J Mol Struct 2011. [DOI: 10.1016/j.molstruc.2011.07.059] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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53
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Nazarski RB, Pasternak B, Leśniak S. Three-component conformational equilibria of some flexible pyrrolidin-2-(thi)ones in solution by NMR data (δC, δH, and nJHH) and their DFT predictions: a confrontation of different approaches. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.06.095] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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54
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Sarotti AM, Suárez AG, Spanevello RA. DFT calculations induced a regiochemical outcome revision of the Diels–Alder reaction between levoglucosenone and isoprene. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.04.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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55
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Bally T, Rablen PR. Quantum-Chemical Simulation of 1H NMR Spectra. 2. Comparison of DFT-Based Procedures for Computing Proton–Proton Coupling Constants in Organic Molecules. J Org Chem 2011; 76:4818-30. [DOI: 10.1021/jo200513q] [Citation(s) in RCA: 144] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Thomas Bally
- Department of Chemistry, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Paul R. Rablen
- Department of Chemistry & Biochemistry, Swarthmore College, Swarthmore, Pennsylvania 19081-1397, United States
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56
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Zhao XZ, Jiang T, Wang L, Yang H, Zhang S, Zhou P. Interaction of curcumin with Zn(II) and Cu(II) ions based on experiment and theoretical calculation. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2010.09.049] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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57
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Barone V, Cimino P, Pedone A. An integrated computational protocol for the accurate prediction of EPR and PNMR parameters of aminoxyl radicals in solution. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2010; 48 Suppl 1:S11-S22. [PMID: 20625984 DOI: 10.1002/mrc.2640] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Magnetic spectroscopic techniques such as electron paramagnetic resonance (EPR) and paramagnetic NMR (PNMR) are valuable tools for understanding the structure and dynamics of complex systems such as, for example, biomolecules or nanomaterials labeled with suitable free radicals. Unfortunately, such spectra do not give direct access to the radical structure because of the subtle interplay between several different effects not easily separable and evaluable by experimentalists alone. In this respect, computational spectroscopy is becoming an essential and versatile tool for the assignment and interpretation of experimental spectra. In this article, the new integrated computational approaches developed in the recent years in our research group are reviewed. Such approaches have been applied to two widely used spin probes showing that proper account of stereo-electronic, environmental and dynamical effects leads to magnetic properties in remarkable agreement with experimental results.
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58
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Bagno A. Computing the NMR spectra of the sponge metabolite arsenicin A: when simple becomes difficult. J PHYS ORG CHEM 2010. [DOI: 10.1002/poc.1719] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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59
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Berionni G, Pégot B, Goumont R. Theoretical and experimental 1H, 13C and 15N NMR studies of N-alkylation of substituted tetrazolo[1,5-a]pyridines. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2010; 48:101-110. [PMID: 19937909 DOI: 10.1002/mrc.2544] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The (15)N as well as (1)H and (13)C chemical shifts of nine substituted tetrazolopyridines and their corresponding tetrazolopyridinium salts have been determined by using NMR spectroscopy at the natural abundance level of all nuclei in CD(3)CN. In this paper, we report, for the first time, the N-alkylation reaction of electron deficient tetrazolopyridines. The treatment of tetrazolopyridines 5-13 with one equivalent of trialkyloxonium tetrafluoroborate leads to a mixture of two isomers, i.e. N3- and N2-alkyl tetrazolo[1,5-a]pyridinium salts. It has been observed that the N3-isomer is always the major isomer, except in the case of the CF(3) substituent, where the two isomers are obtained in the same amount. The quaternary tetrazolopyridinium nitrogen N3 is shielded by around 100 ppm (parts per million) with respect to the parent tetrazolopyridine. Experimental data are interpreted by means of density functional theory (DFT) calculations, including solvent-induced effects, within the conductor-like polarizable continuum model (CPCM). Good agreements between theoretical and experimental (1)H, (13)C and (15)N NMR were found. The combination of multinuclear magnetic resonance spectroscopy with gauge including atomic orbital (GIAO) DFT calculations is a powerful tool in the structural elucidation for both neutral and cationic heterocycles and in the determination of the orientation of N-alkylation of tetrazolopyridines.
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Affiliation(s)
- Guillaume Berionni
- Institut Lavoisier de Versailles, CNRS UMR 8180, Université de Versailles, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France
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Taubert S, Sundholm D, Pichierri F. Magnetically Induced Currents in Bianthraquinodimethane-Stabilized Möbius and Hückel [16]Annulenes. J Org Chem 2009; 74:6495-502. [DOI: 10.1021/jo900736d] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stefan Taubert
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtanens plats 1, Helsinki FIN-00014, Finland
| | - Dage Sundholm
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtanens plats 1, Helsinki FIN-00014, Finland
| | - Fabio Pichierri
- G-COE Laboratory, Department of Applied Chemistry, Graduate School of Engineering, Tohoku University, Aoba-yama 6-6-07, Sendai 980-8579, Japan
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61
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The structure elucidation of a new bromophenol metabolite from Polysiphonia urceolata by experimental and DFT theoretical methods. J Mol Struct 2009. [DOI: 10.1016/j.molstruc.2009.03.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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62
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Molecular structure, NMR analyses, density functional theory and ab initio Hartree–Fock calculations of 3-phenylpropylamine. CR CHIM 2009. [DOI: 10.1016/j.crci.2008.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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63
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d'Antuono P, Botek E, Champagne B, Wieme J, Reyniers MF, Marin GB, Adriaensens PJ, Gelan JM. A joined theoretical-experimental investigation on the 1H and 13C NMR signatures of defects in poly(vinyl chloride). J Phys Chem B 2009; 112:14804-18. [PMID: 18975894 DOI: 10.1021/jp805676q] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1H and 13C chemical shifts of PVC chains have been evaluated using quantum chemistry methods in order to evidence and interpret the NMR signatures of chains bearing unsaturated and branched defects. The geometrical structures of the stable conformers have been determined using molecular mechanics and the OPLS force field and then density functional theory with the B3LYP functional and the 6-311G(d) basis set. The nuclear shielding tensor has been calculated at the coupled-perturbed Kohn-Sham level (B3LYP exchange-correlation functional) using the 6-311+G(2d,p) basis set. The computational scheme accounts for the large number of stable conformers of the PVC chains, and average chemical shifts are evaluated using the Maxwell-Boltzmann distribution. Moreover, the chemical shifts are corrected for the inherent and rather systematic errors of the method of calculation by employing linear regression equations, which have been deduced from comparing experimental and theoretical results on small alkane model compounds containing Cl atoms and/or unsaturations. For each type of defect, PVC segments presenting different tacticities have been considered because it is known from linear PVC chains that the racemic (meso) dyads are characterized by larger (smaller) chemical shifts. NMR signatures of unsaturations in PVC chains have been highlighted for the internal -CH=CH- and -CH=CCl- units as well as for terminal unsaturations like the chloroallylic -CH=CH-CH2Cl group. In particular, the 13C chemical shifts of the two sp2 C atoms are very close for the chloroallylic end group. The CH2 and CHCl units surrounding an unsaturation present also specific 13C chemical shifts, which allow distinguishing them from the others. In the case of the proton, the CH2 unit of the -CHCl-CH2-CCl=CH- segment presents a larger chemical shift (2.6-2.7 ppm), while some CHCl units close to the -CH=CH- unsaturations appear at rather small chemical shifts (3.7 ppm). The -CH2Cl and -CHCl-CH2Cl branches also display specific signatures, which result in large part from modifications of the equilibrium conformations and their reduced number owing to the increased steric interactions. These branches lead to the appearance of 13C peaks at lower field associated either to the CH unit linking the -CH2Cl and -CHCl-CH2Cl branches (50 ppm) or to the CHCl unit of the ethyl branches (60 ppm). The corresponding protons resonate also at specific frequencies: 3.5-4.0 ppm for the -CH2Cl branch or 3.8-4.2 ppm for the terminal unit of the -CHCl-CH2Cl branch. Several of these signatures have been detected in the experimental 1H and 13C NMR spectra and are consistent with the reaction mechanisms.
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Affiliation(s)
- Philippe d'Antuono
- Laboratoire de Chimie Théorique Appliquée, Facultés Universitaires Notre-Dame de la Paix, Namur, Belgium
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64
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Dybiec K, Gryff-Keller A. Remarks on GIAO-DFT predictions of 13C chemical shifts. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2009; 47:63-66. [PMID: 18951367 DOI: 10.1002/mrc.2350] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Predicting (13)C chemical shifts by GIAO-DFT calculations appears to be more accurate than frequently expected provided that: (a) the comparison between experimental and theoretical data is performed using the linear regression method, (b) a sufficiently high level of theory [e.g. B3LYP/6-311 + + G(2d,p)//B3LYP/6-311 + + G(2d,p) or PBE1PBE/6-311 + G(2df,p)//B3LYP/6-311 + + G(2d,p)] is used, (c) the experimental data originate from the measurements performed in one solvent whose influence is taken into account at the molecular geometry optimization step and, first of all, during the shielding calculation, (d) the experimental data are free of heavy atom effects or such effects are appropriately treated in calculations, and finally (e) the conformational compositions of the investigated objects are known.
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Affiliation(s)
- Katarzyna Dybiec
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland
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65
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Senyel M, Alver O, Parlak C. (1)H, (13)C, (15)N NMR and (n)J(C, H) coupling constants investigation of 3-piperidino-propylamine: a combined experimental and theoretical study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 71:830-834. [PMID: 18373948 DOI: 10.1016/j.saa.2008.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 01/29/2008] [Accepted: 02/01/2008] [Indexed: 05/26/2023]
Abstract
Proton coupled and decoupled (13)C, (1)H, (15)N, DEPT, COSY, HETCOR and INADEQUATE NMR spectra of 3-piperidino-propylamine (3-pipa) have been reported for the first time. In order to provide a precise structural elucidation, the magnitude of (n)J(C, H) (n=1, 2, 3) coupling constants of 3-pipa (C(8)H(18)N(2)) have been determined. Solvent effects on chemical shifts have been investigated by using CDCl(3) and DMSO. Molecular mobility of the title molecule has also been investigated by performing (13)C NMR spin-lattice relaxation time (T(1)) measurements. (13)C, (1)H and (15)N NMR chemical shifts and (1-3)J(C, H) coupling constants of 3-pipa have been calculated by means of B3LYP density functional method with 6-311++G(d,p) basis set. Comparison between the experimental and the theoretical results indicates that density functional B3LYP method is able to provide satisfactory results for predicting NMR properties.
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Affiliation(s)
- Mustafa Senyel
- Department of Physics, Science Faculty, Anadolu University, 26470 Eskişehir, Turkey
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66
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Tähtinen P, Saielli G, Guella G, Mancini I, Bagno A. Computational NMR Spectroscopy of Organoarsenicals and the Natural Polyarsenic Compound Arsenicin A. Chemistry 2008; 14:10445-52. [DOI: 10.1002/chem.200801272] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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67
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Fonseca TL, Coutinho K, Canuto S. The isotropic nuclear magnetic shielding constants of acetone in supercritical water: A sequential Monte Carlo/quantum mechanics study including solute polarization. J Chem Phys 2008; 129:034502. [DOI: 10.1063/1.2951995] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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68
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Bagno A, Rastrelli F, Saielli G. Predicting the NMR spectra of nucleotides by DFT calculations: cyclic uridine monophosphate. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2008; 46:518-524. [PMID: 18327890 DOI: 10.1002/mrc.2204] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We present an experimental and quantum chemical NMR study of the mononucleotide cyclic uridine monophosphate in water. Spectral parameters ((1)H and (13)C chemical shifts and (1)H--(1)H, (13)C--(1)H, (31)P--(13)C and (31)P--(1)H spin-spin coupling constants) have been carefully obtained experimentally and calculated using DFT methods including the solvent effect and the conformational flexibility of the solute. This study confirms that the (1)H and (13)C spectra of polar, flexible molecules in aqueous solution can be predicted with a high level of accuracy, comparable to that obtained for less complex systems.
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Affiliation(s)
- Alessandro Bagno
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo, 1-35131 Padova, Italy.
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69
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Smith SG, Paton RS, Burton JW, Goodman JM. Stereostructure Assignment of Flexible Five-Membered Rings by GIAO 13C NMR Calculations: Prediction of the Stereochemistry of Elatenyne. J Org Chem 2008; 73:4053-62. [DOI: 10.1021/jo8003138] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Steven G. Smith
- Unilever Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K., and Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Robert S. Paton
- Unilever Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K., and Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Jonathan W. Burton
- Unilever Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K., and Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Jonathan M. Goodman
- Unilever Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K., and Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
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70
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Santos D, Suardiaz R, Montero LA, Pérez C. DFT analysis of rotational barriers, 1H and 13C NMR chemical shifts in neutral and protonated furfurylidenanilines. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.theochem.2007.12.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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71
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Casabianca LB, de Dios AC. Ab initiocalculations of NMR chemical shifts. J Chem Phys 2008; 128:052201. [DOI: 10.1063/1.2816784] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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72
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Mawhinney RC, Peslherbe GH, Muchall HM. Characterizing Nitrilimines with Nuclear Magnetic Resonance Spectroscopy. A Theoretical Study. J Phys Chem B 2007; 112:650-5. [DOI: 10.1021/jp709968d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Robert C. Mawhinney
- Centre for Research in Molecular Modeling and Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada
| | - Gilles H. Peslherbe
- Centre for Research in Molecular Modeling and Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada
| | - Heidi M. Muchall
- Centre for Research in Molecular Modeling and Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada
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73
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Bagno A, Rastrelli F, Saielli G. Prediction of the 1H and 13C NMR Spectra of α-d-Glucose in Water by DFT Methods and MD Simulations. J Org Chem 2007; 72:7373-81. [PMID: 17718506 DOI: 10.1021/jo071129v] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have applied computational protocols based on DFT and molecular dynamics simulations to the prediction of the alkyl 1H and 13C chemical shifts of alpha-d-glucose in water. Computed data have been compared with accurate experimental chemical shifts obtained in our laboratory. 13C chemical shifts do not show a marked solvent effect. In contrast, the results for 1H chemical shifts provided by structures optimized in the gas phase are only fair and point out that it is necessary to take into account both the flexibility of the glucose structure and the strong effect exerted by solvent water thereupon. Thus, molecular dynamics simulations were carried out to model both the internal geometry as well as the influence of solvent molecules on the conformational distribution of the solute. Snapshots from the simulation were used as input to DFT NMR calculations with varying degrees of sophistication. The most important factor that affects the accuracy of computed 1H chemical shifts is the solute geometry; the effect of the solvent on the shielding constants can be reasonably accounted for by self-consistent reaction field models without the need of explicitly including solvent molecules in the NMR property calculation.
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Affiliation(s)
- Alessandro Bagno
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo, 1-35131 Padua, Italy
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74
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Katritzky AR, Akhmedov NG, Doskocz J, Mohapatra PP, Hall CD, Güven A. NMR spectra, GIAO and charge density calculations of five-membered aromatic heterocycles. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45:532-43. [PMID: 17534885 DOI: 10.1002/mrc.1967] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The B3LYP/6-31+G(d) molecular geometry optimized structures of 17 five-membered heterocycles were employed together with the gauge including atomic orbitals (GIAO) density functional theory (DFT) method at the B3LYP/6-31+G(d,p), B3LYP/6-311++G(d,p) and B3LYP/6-311+G(2d,p) levels of theory for the calculation of proton and carbon chemicals shifts and coupling constants. The method of geometry optimization for pyrrole (1), N-methylpyrrole (2) and thiophene (7) using the larger 6-311++G(d,p) basis sets at the B3LYP/6-31+G(d,p), B3LYP/6-311++G(d,p), B3LYP/6-31+G(2d,p) and B3LYP/cc-pVTZ levels of theory gave little difference between calculated and experimental values of coupling constants. In general, the (1)H and 13C chemical shifts for all compounds are in good agreement with theoretical calculations using the smaller 6-31 basis set. The values of nJHH(n=3, 4, 5) and rmnJ(CH)(n=1, 2, 3, 4) were predicted well using the larger 6-31+G(d,p) and 6-311++G(d,p) basis sets and at the B3LYP/6-31+G(d,p), B3LYP/6-311++G(d,p), B3LYP/6-31+G(2d,2p) levels of theory. The computed atomic charges [Mülliken; Natural Bond Orbital Analysis (NBO); Merz-Kollman (MK); CHELP and CHELPG] for the B3LYP/6-311++G(d,p) geometry optimized structures of 1-17 were used to explore correlations with the experimental proton and carbon chemical shifts.
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Affiliation(s)
- Alan R Katritzky
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611-7200, USA.
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75
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A joined theoretical–experimental investigation on the 1H and 13C NMR chemical shifts of chloro-alkenes. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.01.047] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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76
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Katritzky AR, Akhmedov NG, Doskocz J, Hall CD, Akhmedova RG, Majumder S. Structural elucidation of nitro-substituted five-membered aromatic heterocycles utilizing GIAO DFT calculations. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45:5-23. [PMID: 17042032 DOI: 10.1002/mrc.1894] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The GIAO (Gauge Including Atomic Orbitals) DFT (Density Functional Theory) method is applied at the B3LYP/6-31+G(d,p)//B3LYP/6-31+G(d), B3LYP/6-311++G(d,p)//B3LYP/6-31+G(d), B3LYP/6-311+G (2d,p)//B3LYP/6-31+G(d) and B3LYP/6-311++G(d,p)//B3LYP/6-311++G(d,p) levels of theory for the calculation of proton and carbon chemicals shifts and coupling constants for 25 nitro-substituted five-membered heterocycles. Difference (1D NOE) spectra in combination with long-range gHMBC experiments were used as tools for the structural elucidation of nitro-substituted five-membered heterocycles. The assigned NMR data (chemical shifts and coupling constants) for all compounds were found to be in good agreement with theoretical calculations using the GIAO DFT method. The magnitudes of one-bond (1JCH) and long-range (nJCH, n>1) coupling constants were utilized for unambiguous differentiation between regioisomers of nitro-substituted five-membered heterocycles.
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Affiliation(s)
- Alan R Katritzky
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611-7200, USA.
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77
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78
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Dodziuk H, Ostrowski M. Planarization of the Cyclohexane Ring by Its Incorporation Into a Cyclophane Cage: Hexahydrosuperphane. European J Org Chem 2006. [DOI: 10.1002/ejoc.200600237] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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79
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Bagno A, Kantlehner W, Kress R, Saielli G, Stoyanov E. Fries Rearrangement of Aryl Formates: A Mechanistic Study by Means of 1H, 2H, and 11B NMR Spectroscopy and DFT Calculations. J Org Chem 2006; 71:9331-40. [PMID: 17137359 DOI: 10.1021/jo061475x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1H, 2H, and 11B NMR spectroscopy has been used to study the mechanism of the Fries rearrangement of aryl formates promoted by boron trichloride by monitoring both the substrate and the Lewis acid. DFT calculations were employed to investigate the energetics of several reaction paths and to calculate NMR chemical shifts of key intermediates and products. After the formation of a 1:1 substrate-Lewis acid adduct, the rearrangement proceeds in two steps, beginning with the cleavage of the ester bond and the release of formyl chloride in situ, which, in turn, acts as a formylating agent, introducing an aldehydic functionality into the aromatic ring. The high regioselectivity (only the ortho product is obtained) is also accounted for by the proposed intermolecular, Lewis acid-assisted mechanism.
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Affiliation(s)
- Alessandro Bagno
- Dipartimento di Scienze Chimiche, Università di Padova, Via Marzolo, 1 35131 Padova, Italy
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80
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Abildgaard J, Hansen PE, Josephsen J, Hansen BK, Sørensen HO, Larsen S. Synthesis and characterization of nickel-, palladium- and platinum(II) complexes of three o,o′-dihydroxydiarylazo dyes: Determination of the coordination geometry of this comprehensive series of tridentate diaryl dye complexes by combining results from NMR and X-ray experiments with theoretical ab initio calculations. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2006.05.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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81
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d'Antuono P, Botek E, Champagne B, Spassova M, Denkova P. Theoretical investigation on H1 and C13 NMR chemical shifts of small alkanes and chloroalkanes. J Chem Phys 2006; 125:144309. [PMID: 17042592 DOI: 10.1063/1.2353830] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Using density functional theory (DFT) with the B3LYP, PBE, and PBE0 exchange-correlation functionals as well as the Moller-Plesset second-order perturbation theory (MP2) combined with a series of rather extended basis sets, 1H and 13C chemical shifts of small alkanes and chloroalkanes (with different numbers of chlorine atoms on specific positions) have been simulated and compared to experimental data. For the 1H chemical shifts, theory tends to reproduce experiment within the limits of the experimental errors. In the case of 13C chemical shift, the differences between theory and experiment increase monotonically with the number of chlorine atoms and exhibit a deviation from additivity. This behavior is related to the saturation of the experimental 13C chemical shifts with the number of chlorine atoms, whereas the evolution is mostly linear at both DFT and MP2 levels of approximation. This difference has been traced back to the relativistic spin-orbit coupling effects, which are exalted as a result of the enhancement of the s character of the C atom when increasing the number of linked Cl atoms. Thus, it was demonstrated that not only electron correlation but also relativistic effects have to be considered for estimating the 13C chemical shifts when several Cl atoms are directly attached to the C atom. Linear (theory/experiment) regressions have then been performed for the different types of C atoms, i.e., bearing one, two, and three Cl atoms, with excellent correlation coefficients. The linear correlation relationships so obtained can then serve to predict and facilitate the interpretation of the nuclear magnetic resonance spectra of more complex compounds. Furthermore, by investigating the basis set effects, the correlation between the chemical shifts calculated using the 6-311 + G(2d,p) basis set and the more extended 6-311 + G(2df,p) and aug-cc-pvtz basis sets is excellent, demonstrating that the choice of the 6-311 + G(2d,p) basis set for calculating the 1H and 13C chemical shifts is relevant.
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Affiliation(s)
- Philippe d'Antuono
- Laboratoire de Chimie Théorique Appliquée, Facultés Universitaires Notre-Dame de la Paix, rue de Bruxelles, 61, B-5000 Namur, Belgium
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82
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Rastrelli F, Bagno A. Selective J-resolved spectra: a double pulsed field gradient spin-echo approach. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 182:29-37. [PMID: 16807018 DOI: 10.1016/j.jmr.2006.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 04/24/2006] [Accepted: 06/05/2006] [Indexed: 05/10/2023]
Abstract
A simple method to obtain selective J-resolved spectra is presented, which relies on the refocusing properties of double pulsed field gradient spin-echoes and provides unambiguous assignment of the measured coupling constants. The proposed examples show how this method is of general applicability, and requires no more than a simple optimization strategy to produce artifact-free spectra. Examples of application include the determination of a small, long-range coupling constant (0.7 Hz) in trans-retinal and Halpha couplings in a tripeptide.
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Affiliation(s)
- Federico Rastrelli
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy.
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83
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Bagno A, Rastrelli F, Saielli G. Toward the Complete Prediction of the1H and13C NMR Spectra of Complex Organic Molecules by DFT Methods: Application to Natural Substances. Chemistry 2006; 12:5514-25. [PMID: 16680788 DOI: 10.1002/chem.200501583] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The NMR parameters (1H and 13C chemical shifts and coupling constants) for a series of naturally occurring molecules have been calculated mostly with DFT methods, and their spectra compared with available experimental ones. The comparison includes strychnine as a test case, as well as some examples of recently isolated natural products (corianlactone, daphnipaxinin, boletunone B) featuring unusual and/or crowded structures and, in the case of boletunone B, being the subject of a recent revision. Whenever experimental spectra were obtained in polar solvents, the calculation of NMR parameters was also carried out with the Integral Equation-Formalism Polarizable Continuum Model (IEF-PCM) continuum method. The computed results generally show a good agreement with experiment, as judged not only by statistical parameters but also by visual comparison of line spectra. The origin of the remaining discrepancies is attributed to the incomplete modeling of conformational and specific solvent effects.
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Affiliation(s)
- Alessandro Bagno
- Dipartimento di Scienze Chimiche, Università di Padova, Padua, Italy.
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84
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Alcântara AFC, Piló-Veloso D, Almeida WBD, Maltha CR, Barbosa LCA. Conformational analysis of 8-oxabicyclo[3.2.1]oct-6-en-3-one derivatives by NMR and theoretical calculations. J Mol Struct 2006. [DOI: 10.1016/j.molstruc.2006.01.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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85
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Mulholland DA, Langlois A, Randrianarivelojosia M, Derat E, Nuzillard JM. The structural elucidation of a novel iridoid derivative from Tachiadenus longiflorus (Gentianaceae) using the LSD programme and quantum chemical computations. PHYTOCHEMICAL ANALYSIS : PCA 2006; 17:87-90. [PMID: 16634284 DOI: 10.1002/pca.890] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Oleanolic acid, scoparone, scopoletin and a novel iridoid derivative, angelone, were isolated from Tachiadenus longiflorus (Gentianaceae). The structure of angelone was determined from NMR data, given as input to the Logic for Structure Determination Programme, and was finally confirmed by comparison of experimental 13C-NMR chemical shifts with those obtained by quantum mechanical calculations.
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Affiliation(s)
- D A Mulholland
- Natural Products Research Group, School of Chemistry, University of KwaZulu-Natal, Durban 4041, South Africa
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86
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Pavone M, Brancato G, Morelli G, Barone V. Spectroscopic Properties in the Liquid Phase: Combining High-Level Ab Initio Calculations and Classical Molecular Dynamics. Chemphyschem 2006; 7:148-56. [PMID: 16331721 DOI: 10.1002/cphc.200500357] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We present an integrated computational tool, rooted in density functional theory, the polarizable continuum model, and classical molecular dynamics employing spherical boundary conditions, to study the spectroscopic observables of molecules in solution. As a test case, a modified OPLS-AA force field has been developed and used to compute the UV and NMR spectra of acetone in aqueous solution. The results show that provided the classical force fields are carefully reparameterized and validated, the proposed approach is robust and effective, and can also be used by nonspecialists to provide a general and powerful complement to experimental techniques.
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Affiliation(s)
- Michele Pavone
- Dipartimento di Chimica, Università di Napoli Federico II, Complesso Universitario di Monte Sant'Angelo, Via Cintia, 80126 Napoli, Italy
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87
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Bagno A, Casella G, Saielli G. Relativistic DFT Calculation of 119Sn Chemical Shifts and Coupling Constants in Tin Compounds. J Chem Theory Comput 2005; 2:37-46. [DOI: 10.1021/ct050173k] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alessandro Bagno
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo, 1-35131 Padova, Italy, Dipartimento di Chimica Inorganica e Analitica “Stanislao Cannizzaro”, Università di Palermo, Viale delle Scienze Parco d'Orleans II, 90128 Palermo, Italy, and Istituto CNR per la Tecnologia delle Membrane, Sezione di Padova, via Marzolo, 1-35131 Padova, Italy
| | - Girolamo Casella
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo, 1-35131 Padova, Italy, Dipartimento di Chimica Inorganica e Analitica “Stanislao Cannizzaro”, Università di Palermo, Viale delle Scienze Parco d'Orleans II, 90128 Palermo, Italy, and Istituto CNR per la Tecnologia delle Membrane, Sezione di Padova, via Marzolo, 1-35131 Padova, Italy
| | - Giacomo Saielli
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo, 1-35131 Padova, Italy, Dipartimento di Chimica Inorganica e Analitica “Stanislao Cannizzaro”, Università di Palermo, Viale delle Scienze Parco d'Orleans II, 90128 Palermo, Italy, and Istituto CNR per la Tecnologia delle Membrane, Sezione di Padova, via Marzolo, 1-35131 Padova, Italy
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88
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Dodziuk H, Jaszuński M, Schilf W. 1H and 13C NMR chemical shifts and spin-spin coupling constants in trans- and cis-decalins. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2005; 43:639-46. [PMID: 15915544 DOI: 10.1002/mrc.1598] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The NMR parameters characterizing the spectra of trans- and cis-decalins were determined from theoretical calculations and experimental spectra. The calculated values of the shielding constants are in good agreement with the measured chemical shifts, with a small but noticeable difference in accuracy for the bridgehead atoms. Of all the spin-spin coupling constants, only most of (1)J(C,C) and (1)J(C,H) values could be extracted from the spectra, and the corresponding computed values are in good agreement with experiment. It appears that the applied density functional theory (DFT) approach overestimates slightly the J(C,C) coupling and underestimates the differences between one-bond (1)J(C,H) coupling constants. For all these constants [J(C,C), J(C,H) and J(H,H)] through one to three bonds, which could not be obtained experimentally, the predicted values are in good agreement with the general rules relating spin-spin coupling to the number and spatial arrangement of the intervening bonds.
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Affiliation(s)
- Helena Dodziuk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
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89
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d’Antuono P, Botek E, Champagne B, Wieme J, Reyniers MF, Marin GB, Adriaensens PJ, Gelan JM. Density functional theory investigation of the stereochemistry effects on 1H and 13C NMR chemical shifts of poly(vinyl chloride) oligomers. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.06.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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90
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Rautiainen JM, Way T, Schatte G, Passmore J, Laitinen RS, Suontamo RJ, Valkonen J. A Computational and Experimental Study of the Structures and Raman and 77Se NMR Spectra of SeX3+ and SeX2 (X = Cl, Br, I): FT-Raman Spectrum of (SeI3)[AsF6]. Inorg Chem 2005; 44:1904-13. [PMID: 15762716 DOI: 10.1021/ic048310w] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability of MP2, B3PW91 and PBE0 methods to produce reliable predictions in structural and spectroscopic properties of small selenium-halogen molecules and cations has been demonstrated by using 6-311G(d) and cc-pVTZ basis sets. Optimized structures and vibrational frequencies agree closely with the experimental information, where available. Raman intensities are also well reproduced at all levels of theory. Calculated GIAO isotropic shielding tensors yield a reasonable linear correlation with the experimental chemical shift data at each level of theory. The largest deviations between calculated and experimental chemical shifts are found for selenium-iodine species. The agreement between observed and calculated chemical shifts for selenium-iodine species can be improved by inclusion of relativistic effects using the ZORA method. The best results are achieved by adding spin-orbit correction terms from ZORA calculations to nonrelativistic GIAO isotropic shielding tensors. The calculated isotropic shielding tensors can be utilized in the spectroscopic assignment of the 77Se chemical shifts of novel selenium-halogen molecules and cations. The experimental FT-Raman spectra of (SeI3)[AsF6] in the solid state and in SO2(l) solution are also reported.
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Affiliation(s)
- J Mikko Rautiainen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, FIN-40014, Finland
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91
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Johansson P. Illustrative direct ab initio calculations of surface Raman spectra. Phys Chem Chem Phys 2005; 7:475-82. [DOI: 10.1039/b415535a] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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92
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Taubert S, Konschin H, Sundholm D. Computational studies of 13C NMR chemical shifts of saccharides. Phys Chem Chem Phys 2005; 7:2561-9. [PMID: 16189565 DOI: 10.1039/b505546f] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The (13)C NMR chemical shifts for alpha-D-lyxofuranose, alpha-D-lyxopyranose (1)C(4), alpha-D-lyxopyranose (4)C(1), alpha-D-glucopyranose (4)C(1), and alpha-D-glucofuranose have been studied at ab initio and density-functional theory levels using TZVP quality basis set. The methods were tested by calculating the nuclear magnetic shieldings for tetramethylsilane (TMS) at different levels of theory using large basis sets. Test calculations on the monosaccharides showed B3LYP(TZVP) and BP86(TZVP) to be cost-efficient levels of theory for calculation of NMR chemical shifts of carbohydrates. The accuracy of the molecular structures and chemical shifts calculated at the B3LYP(TZVP) level is comparable to those obtained at the MP2(TZVP) level. Solvent effects were considered by surrounding the saccharides by water molecules and also by employing a continuum solvent model. None of the applied methods to consider solvent effects was successful. The B3LYP(TZVP) and MP2(TZVP)(13)C NMR chemical shift calculations yielded without solvent and rovibrational corrections an average deviation of 5.4 ppm and 5.0 ppm between calculated and measured shifts. A closer agreement between calculated and measured chemical shifts can be obtained by using a reference compound that is structurally reminiscent of saccharides such as neat methanol. An accurate shielding reference for carbohydrates can be constructed by adding an empirical constant shift to the calculated chemical shifts, deduced from comparisons of B3LYP(TZVP) or BP86(TZVP) and measured chemical shifts of monosaccharides. The systematic deviation of about 3 ppm for O(1)H chemical shifts can be designed to hydrogen bonding, whereas solvent effects on the (1)H NMR chemical shifts of C(1)H were found to be small. At the B3LYP(TZVP) level, the barrier for the torsional motion of the hydroxyl group at C(6) in alpha-D-glucofuranose was calculated to 7.5 kcal mol(-1). The torsional displacement was found to introduce large changes of up to 10 ppm to the (13)C NMR chemical shifts yielding uncertainties of about +/-2 ppm in the chemical shifts.
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Affiliation(s)
- Stefan Taubert
- Department of Chemistry, University of Helsinki, P.O. Box 55 A.I. Virtanens plats 1, FIN-00014 Helsinki, Finland
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93
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Crescenzi O, Pavone M, De Angelis F, Barone V. Solvent Effects on the UV (n → π*) and NMR (13C and 17O) Spectra of Acetone in Aqueous Solution. An Integrated Car−Parrinello and DFT/PCM Approach. J Phys Chem B 2004; 109:445-53. [PMID: 16851035 DOI: 10.1021/jp046334i] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The accurate reproduction of ultraviolet and nuclear magnetic resonance spectra of acetone in aqueous solution is used as a test of an integrated computational tool rooted in the density functional theory, the polarizable continuum model, and the Car-Parrinello dynamics. The analysis and solution of several conceptual and practical issues results in a robust and effective approach, which also can be used by nonspecialists and provides a general and powerful complement to experimental techniques.
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Affiliation(s)
- Orlando Crescenzi
- Dipartimento di Chimica, Università di Napoli Federico II, Complesso Universitario di Monte Sant'Angelo, Via Cintia, I-80126 Napoli, Italy
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94
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Gauze GF, Pontes RM, Basso EA. A factorial design analysis of wave functions to be used in calculations of NMR parameters of ketones. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2004.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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95
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Tähtinen P, Bagno A, Koch A, Pihlaja K. Conformational Analysis of Saturatedtrans-Fused 1,3,2-Benzoxazaphosphinine 2-Oxides − DFT Calculation of NMRJ(P,H) Coupling Constants. European J Org Chem 2004. [DOI: 10.1002/ejoc.200400447] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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96
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Ro??i? M, Eklund R, Nordmark EL, Horvat ?, Widmalm G. Stereochemical Assignment of Diastereomeric Imidazolidinone-Ring-Containing Bicyclic Sugar-Peptide Adducts: NMR Spectroscopy and Molecular Calculations. European J Org Chem 2004. [DOI: 10.1002/ejoc.200400391] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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97
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Bagno A, Saielli G. Calculation of NMR parameters in van der Waals complexes involving organic systems and xenon. J PHYS ORG CHEM 2004. [DOI: 10.1002/poc.815] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Alessandro Bagno
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
| | - Giacomo Saielli
- Istituto per la Tecnologia delle Membrane del CNR, Sezione di Padova, via Marzolo 1, 35131 Padova, Italy
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98
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Brynda M, Wesolowski TA, Wojciechowski K. Theoretical Investigation of the Anion Binding Affinities of the Uranyl Salophene Complexes. J Phys Chem A 2004. [DOI: 10.1021/jp049404u] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marcin Brynda
- Department of Chemistry, University of California Davis, One Shields Avenue, Davis, California 95616, Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland, and Department of Analytical, Inorganic and Applied Chemistry, University of Geneva, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
| | - Tomasz A. Wesolowski
- Department of Chemistry, University of California Davis, One Shields Avenue, Davis, California 95616, Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland, and Department of Analytical, Inorganic and Applied Chemistry, University of Geneva, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
| | - Kamil Wojciechowski
- Department of Chemistry, University of California Davis, One Shields Avenue, Davis, California 95616, Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland, and Department of Analytical, Inorganic and Applied Chemistry, University of Geneva, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
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99
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Crescenzi O, Correale G, Bolognese A, Piscopo V, Parrilli M, Barone V. Observed and calculated 1H- and 13C-NMR chemical shifts of substituted 5H-pyrido[3,2-a]- and 5H-pyrido[2,3-a]phenoxazin-5-ones and of some 3H-phenoxazin-3-one derivatives. Org Biomol Chem 2004; 2:1577-81. [PMID: 15162207 DOI: 10.1039/b401147c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Carbon and proton NMR spectra of several substituted 5H-pyrido[3,2-a]-, 5H-pyrido[2,3-a]phenoxazin-5-ones and 3H-phenoxazin-3-one derivatives have been assigned, and the experimental chemical shifts have been compared with the results of density functional calculations employing large basis sets. Solvent effects were explored by means of the polarizable continuum method (PCM), while the (limited) side-chain flexibility of the compounds has been addressed by Boltzmann averaging of the computed spectral parameters over different conformational minima. Overall, the calculated shifts reproduce well the experiment results; thus, the computational procedure represents a feasible and useful complement to multidimensional NMR experiments in the assignment process.
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Affiliation(s)
- Orlando Crescenzi
- Department of Chemistry, University of Naples Federico II, Via Cintia, I-80126 Naples, Italy
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100
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Bifulco G, Bassarello C, Riccio R, Gomez-Paloma L. Quantum Mechanical Calculations of NMR J Coupling Values in the Determination of Relative Configuration in Organic Compounds. Org Lett 2004; 6:1025-8. [PMID: 15012091 DOI: 10.1021/ol049913e] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text] An approach relying on quantum mechanical calculations of proton-proton and proton-carbon J coupling values is proposed as a tool for assigning the relative configuration on chiral organic compounds. The method is suitable for carbon frameworks containing several adjacent stereogenic centers and may allow significant advances in the extensive use of spin-spin couplings in structural elucidation.
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Affiliation(s)
- Giuseppe Bifulco
- Dipartimento di Scienze Farmaceutiche, Università di Salerno, 84084 Fisciano (SA), Italy.
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