Simulation of 2D 1 H homo- and 1 H– 13 C heteronuclear NMR spectra of organic molecules by DFT calculations of spin–spin coupling constants and 1 H and 13 C-chemical shifts

The 13C, 69/71Ga and 115In NMR spectra of lithium tetra(tert-butyl)gallate and -indate were measured under various conditions. It proved possible to determine for the first time the coupling constants 1J(69/71Ga,13C) = 182 Hz/232 Hz and 1J(115In,13C) = 310±10 Hz for these metallates under conditions for solvent-separated ions. DFT calculations [B3LYP/6-311+G(d,p)] were carried out for organogallium compounds such as tri(tert-butyl)gallium, trimethylgallium and tetramethylgallate in order to predict and confirm coupling constants 1J(Ga,13C).

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Prediction of the1H NMR spectra of epoxy-fused cyclopentane derivatives by calculations of chemical shifts and spin–spin coupling constants

Molecular Physics ◽

10.1080/00268976.2013.772256 ◽

2013 ◽

Vol 111 (20) ◽

pp. 3147-3155

Author(s):

C. Özen ◽

A. Yıldırım ◽

N. Ş. Tüzün ◽

P. Haslak ◽

E. Doğan ◽

...

Keyword(s):

Nmr Spectra ◽

Chemical Shifts ◽

Coupling Constants ◽

Spin Coupling ◽

Spin Coupling Constants ◽

Spin Spin Coupling

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1H, 1 3C, and 1 5N Chemical shifts and 1H-1 5N and 1 3C-1 5N heteronuclear spin-spin coupling constants in the NMR spectra of 5-substituted furfural oximes

Chemistry of Heterocyclic Compounds ◽

10.1007/bf00515016 ◽

1985 ◽

Vol 21 (9) ◽

pp. 974-979 ◽

Cited By ~ 7

Author(s):

Yu. Yu. Popelis ◽

�. �. Liepin'sh ◽

E. Ya. Lukevits

Keyword(s):

Nmr Spectra ◽

Chemical Shifts ◽

Coupling Constants ◽

Spin Coupling ◽

Spin Coupling Constants ◽

Spin Spin Coupling

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

Organic Chemistry Frontiers ◽

10.1039/d1qo00034a ◽

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...

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Hyperconjugation In Trialkylboranes Shown By Indirect Nuclear Spin-Spin Coupling Constants. Experimental Data And Density Functional Theory (Dft) Calculations

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-0304 ◽

2005 ◽

Vol 60 (3) ◽

pp. 259-264 ◽

Cited By ~ 29

Author(s):

Bernd Wrackmeyer ◽

Oleg L. Tok

Keyword(s):

Experimental Data ◽

Dft Calculations ◽

Density Functional ◽

Calculated Data ◽

Coupling Constants ◽

Spin Coupling ◽

Functional Theory ◽

Spin Coupling Constants ◽

Spin Spin Coupling ◽

C Nmr

Trimethylborane (1), triethylborane (2), 1,3-dimethyl-1-boracyclopentane (3), 1-methyl-1- boracyclohexane (4), 9-methyl- and 9-ethyl-9-borabicyclo[3.1.1]nonane [5(Me) and 5(Et)], and 1- boraadamantane (6) were studied by 11B and 13C NMR spectroscopy with respect to coupling constants 1J(13C,11B) and 1J(13C,13C). Results of DFT calculations at the B3LYP/6-311+g(d,p) level of theory show satisfactory agreement with the experimental data. Hyperconjugation arising from C-C σ bonds adjacent to the tricoordinate boron atom is indicated, in particular for 1-boraadamantane (6), by the optimised calculated structures, and by the experimental and calculated data 1J(13C,13C). The calculated magnitude of 1J(13C,1H) for carbon atoms adjacent to boron becomes significantly smaller if the optimised structures suggest hyperconjugative effects arising from these C-H bonds

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The planar conformation of 2-methylthiobenzaldehyde in solution

Canadian Journal of Chemistry ◽

10.1139/v83-005 ◽

1983 ◽

Vol 61 (1) ◽

pp. 26-28

Author(s):

Ted Schaefer ◽

Rudy Sebastian

Keyword(s):

Chemical Shifts ◽

Coupling Constants ◽

Spin Coupling ◽

Spectral Parameters ◽

H Nmr ◽

Heavy Atoms ◽

Planar Conformation ◽

Spin Coupling Constants ◽

Spin Spin Coupling ◽

Infrared Data

The 1H nmr spectral parameters are extracted for a 4 mol% solution of 2-methylthiobenzaldehyde in CCl4 at 305 K. The long-range spin–spin coupling constants involving the aldehydic and methyl protons are consistent only with a preferred conformation in which all heavy atoms are coplanar, as are the chemical shifts of the ring and methyl protons. This conclusion contradicts previous interpretations of the dipole moment, the nmr parameters, and of the infrared data for CCl4 solutions. The present data show that the O-syn and O-anti forms of the compound are present in roughly equal proportions.

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