Quantitation of deuterium-hydrogen NMR isotope effects on carbon-13 chemical shifts. Linear correlations associated with hybridization and charge density changes in norbornenyl systems

1986 ◽  
Vol 108 (25) ◽  
pp. 8089-8091 ◽  
Author(s):  
Hermann. Kuenzer ◽  
Charles E. Cottrell ◽  
Leo A. Paquette
Keyword(s):  
Charge Density ◽  
Chemical Shifts ◽  
Isotope Effects ◽  
Linear Correlations

scholarly journals NMR of Natural Products as Potential Drugs

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3763
Author(s):  
Poul Erik Hansen
Keyword(s):  
Natural Products ◽  
Hydrogen Bonding ◽  
Density Functional ◽  
Chemical Shifts ◽  
Isotope Effects ◽  
Density Functional Theory Calculations ◽  
Intramolecular Hydrogen Bonding ◽  
Chemical Equilibria ◽  
Nmr Techniques ◽  
Intramolecular Hydrogen

This review outlines methods to investigate the structure of natural products with emphasis on intramolecular hydrogen bonding, tautomerism and ionic structures using NMR techniques. The focus is on 1H chemical shifts, isotope effects on chemical shifts and diffusion ordered spectroscopy. In addition, density functional theory calculations are performed to support NMR results. The review demonstrates how hydrogen bonding may lead to specific structures and how chemical equilibria, as well as tautomeric equilibria and ionic structures, can be detected. All these features are important for biological activity and a prerequisite for correct docking experiments and future use as drugs.

Hydrogen/Deuterium-Isotope Effects on NMR Chemical Shifts and Symmetry of Homoconjugated Hydrogen-Bonded Ions in Polar Solution

2000 ◽  
Vol 122 (51) ◽  
pp. 12878-12879 ◽  
Author(s):  
Parwin Schah-Mohammedi ◽  
Ilja G. Shenderovich ◽  
Carsten Detering ◽  
Hans-Heinrich Limbach ◽  
Peter M. Tolstoy ◽  
...  
Keyword(s):  
Chemical Shifts ◽  
Isotope Effects ◽  
Polar Solution ◽  
Nmr Chemical Shifts ◽  
Hydrogen Deuterium ◽  
Deuterium Isotope Effects ◽  
Hydrogen Bonded

Carbon-13/carbon-12 isotope effects on nitrogen-15 chemical shielding in some diamagnetic cyano complexes

1982 ◽  
Vol 60 (17) ◽  
pp. 2194-2197 ◽  
Author(s):  
Roderick E. Wasylishen
Keyword(s):  
Transition Metal ◽  
High Field ◽  
Chemical Shifts ◽  
Isotope Effects ◽  
Chemical Shielding ◽  
Cyanide Ion ◽  
Theoretical Formulation ◽  
Metal Cyanides ◽  
Shielding Constants ◽  
Cyano Complexes

Carbon-13/carbon-12 isotope-induced 15N chemical shifts of 0.06 to 0.10 ppm have been observed for the cyanide ion and several transition metal cyanides. In each case, the 15N resonance of the 13C labelled isotopomers is to high field of that in the corresponding carbon-12 species. The sensitivity of the 15N and 13C shielding constants in the cyanide ion to small changes in the CN bond length are evaluated using the theoretical formulation of Jameson: (∂σ(15N)/∂r)e = −872 ± 160 ppm/Å and (∂σ(13C)/∂r)e = −473 ± 90 ppm/Å. Nitrogen-15 chemical shifts in the metal complexes exhibit basically the same behaviour as do the 13C chemical shifts in these same complexes.

Deuterium Isotope Effects on13C NMR Chemical Shifts Reflect the Smaller Steric Size of CD3Compared to CH3Groups§

2000 ◽  
Vol 2 (25) ◽  
pp. 4111-4113 ◽  
Author(s):  
Kerstin Ibrom ◽  
Gunther Kohn ( ◽  
Kai-Uwe Boeckmann ◽  
Roswitha Kraft ◽  
Petra Holba-Schulz ◽  
...  
Keyword(s):  
Chemical Shifts ◽  
Isotope Effects ◽  
Nmr Chemical Shifts ◽  
Deuterium Isotope Effects

Tritium isotope effects on carbon-13 NMR chemical shifts

1986 ◽  
Vol 108 (6) ◽  
pp. 1356-1357 ◽  
Author(s):  
Cheryl H. Arrowsmith ◽  
Lars. Baltzer ◽  
A. Jerry. Kresge ◽  
Michael F. Powell ◽  
Yui S. Tang
Keyword(s):  
Chemical Shifts ◽  
Isotope Effects ◽  
Nmr Chemical Shifts

Cyclic trimers of phosphinic acids in polar aprotic solvent: symmetry, chirality and H/D isotope effects on NMR chemical shifts

2018 ◽  
Vol 20 (7) ◽  
pp. 4901-4910 ◽  
Author(s):  
V. V. Mulloyarova ◽  
I. S. Giba ◽  
M. A. Kostin ◽  
G. S. Denisov ◽  
I. G. Shenderovich ◽  
...  
Keyword(s):  
Aprotic Solvent ◽  
Chemical Shifts ◽  
Isotope Effects ◽  
Nmr Chemical Shifts ◽  
Polar Aprotic Solvent ◽  
Phosphinic Acids ◽  
Proton Chemical Shifts ◽  
Bonded Complexes ◽  
Hydrogen Bonded

By using NMR in liquefied gases, the stoichiometry of hydrogen-bonded complexes is determined via H/D isotope effects on proton chemical shifts.

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