2-Deoxy-β-d-erythro-pentofuranose:  Hydroxymethyl Group Conformation and Substituent Effects on Molecular Structure, Ring Geometry, and NMR Spin−Spin Coupling Constants from Quantum Chemical Calculations

2001 ◽  
Vol 123 (20) ◽  
pp. 4781-4791 ◽  
Author(s):  
Francis Cloran ◽  
Ian Carmichael ◽  
Anthony S. Serianni
Keyword(s):  
Molecular Structure ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Substituent Effects ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Hydroxymethyl Group ◽  
Ring Geometry ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling

The Molecular Structure of Allenes and Ketenes, XIII Correlations of Carbon-Proton Spin-Spin Coupling Constants in Allenes with ab initio STO-3G Overlap Populations

1979 ◽  
Vol 34 (1) ◽  
pp. 118-120 ◽  
Author(s):  
Wolfgang Runge
Keyword(s):  
Molecular Structure ◽  
Ab Initio ◽  
Substituent Effects ◽  
Proton Spin ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Proton Coupling ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
Cl Atoms

Abstract It is shown that substituent effects on one-bond and long-range carbon-proton coupling constants in monosubstituted allenes parallel quantitatively ab initio STO-3G carbon 2s-hydrogen 1 s overlap populations, irrespectively of whether the substituents are bonded to the allenic skeleton via first-row (C, O) or second-row (Si, S, Cl) atoms.

Structural Characterization of Natural Products By Means of Quantum Chemical Calculations of NMR Parameters: New insights

2021 ◽  
Author(s):  
Fabio Luiz Paranhos Costa ◽  
Ana Carolina Ferreira de Albuquerque ◽  
Rodolfo Goetze Fiorot ◽  
Luciano Morais Lião ◽  
Lucas Haidar Martorano ◽  
...  
Keyword(s):  
Natural Products ◽  
Structural Characterization ◽  
Quantum Chemical ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Nmr Parameters ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling

The calculation of NMR parameters for natural products was pioneered by Bifulco and coworkers in 2002. Since then, modelling 1H and 13C chemical shifts and spin-spin coupling constants for this...

9-Borafluorenes – NMR spectroscopy and DFT calculations. Molecular structure of 1,2-(2,2′-diphenylylene)-1,2-diethyldiborane

2010 ◽  
Vol 75 (7) ◽  
pp. 743-756 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Peter Thoma ◽  
Rhett Kempe ◽  
Germund Glatz
Keyword(s):  
Molecular Structure ◽  
Nmr Spectroscopy ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Spin Coupling ◽  
X Ray Diffraction ◽  
Data Set ◽  
Chemical Shift Tensors ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling

9-Borafluorene derivatives 1 (9-R = Et (a), Ph (b), Cl (c), NEt2 (d)), the pyridine adduct 1py+ and 1,2-(2,2′-biphenylylene)-1,2-diethyldiborane(6) (3), were studied by 11B and 13C NMR spectroscopy to obtain a fairly complete data set for the first time. The molecular structure of the doubly hydrogen-bridged 1,2-diphenylenediborane 3 was determined by X-ray diffraction. The gas-phase structures of the compounds 1, related derivatives, and of some doubly hydrogen-bridged 1,2-diphenylenediboranes were optimized by quantum chemical calculations (B3LYP/6-311+G(d,p) level of theory) and NMR parameters, such as chemical shifts, 11B chemical shift tensors and indirect nuclear 13C–11B spin–spin coupling constants were calculated at the same level of theory and compared with experimental data.

Quantum chemical analysis of the orientational lone-pair effect on spin-spin coupling constants

1990 ◽  
Vol 210 ◽  
pp. 175-186 ◽  
Author(s):  
R.H. Contreras ◽  
C.G. Giribet ◽  
M.C.Ruiz De Azúa ◽  
C.N. Cavasotto ◽  
G.A. Aucar ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Quantum Chemical ◽  
Lone Pair ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Quantum Chemical Analysis ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling
Sign in / Sign up

Export Citation Format

Share Document