ChemInform Abstract: NMR SPECTRA OF ALKALI AND HALOGEN NUCLEI IN ALKALI AND HALOGEN SALTS

1978 ◽  
Vol 9 (44) ◽  
Author(s):  
W. GAUSS ◽  
S. GUENTHER ◽  
A. R. HAASE ◽  
M. KERBER ◽  
D. KESSLER ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Halogen Salts

NMR Spectra of Alkali and Halogen Nuclei in Alkali and Halogen Salts

1978 ◽  
Vol 33 (8) ◽  
pp. 934-939 ◽  
Author(s):  
W. Gauß ◽  
S. Günther ◽  
A. R. Haase ◽  
M. Kerber ◽  
D. Kessler ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Alkali Halides ◽  
Coupling Constants ◽  
Magnetic Shielding ◽  
First Order ◽  
Quadrupole Coupling ◽  
Shielding Constants ◽  
Order Of Magnitude ◽  
Nmr Signals ◽  
Halogen Salts

NMR signals of 7Li, 23Na, 35Cl, 39K, 79Br, 87Rb and 127I have been measured in various alkali and halogen salt powders relative to well defined aqueous solutions. With the known shielding constants of some of these solutions the nuclear magnetic shielding constants of the alkali and chlorine nuclei in crystalline powders were evaluated in the atomic reference scale. The theoretical values of the shielding constants in alkali halides do not agree even in the order of magnitude with the experimental ones in some cases.For 23Na first-order and second-order quadrupole patterns have been observed and the quadrupole coupling constants are given.

NMR spectra and relaxation in incommensurate systems in the presence of a devil's staircase

1985 ◽  
Vol 46 (7) ◽  
pp. 1205-1209 ◽  
Author(s):  
R. Blinc ◽  
S. Žumer ◽  
D.C. Ailion ◽  
J. Nicponski
Keyword(s):  
Nmr Spectra ◽  
Devil's Staircase ◽  
Devil’S Staircase

Some Considerations Regarding the 1H and 13C Spectra of 4-(1-azulenyl)-2,6-bis(2-heteroaryl-vinyl)- pyrylium and Pyridinium and their Corresponding Pyridines

2018 ◽  
Vol 69 (1) ◽  
pp. 64-69
Author(s):  
Liviu Birzan ◽  
Mihaela Cristea ◽  
Constantin C. Draghici ◽  
Alexandru C. Razus
Keyword(s):  
Double Bond ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Pyridinium Salts ◽  
13C Nmr Spectra ◽  
1H And 13C Nmr ◽  
Pyrylium Salts

The 1H and 13C NMR spectra of several 2,6-diheteroarylvinyl heterocycles containing 4-azulenyl moiety were recorded and their proton and carbon chemical shifts were compared with those of the compounds without double bond between the heterocycles. The influence of the nature of central and side heterocycles, molecule polarization and anisotropic effects were revealed. The highest chemical shifts were recorded for the pyrylium salts and the lowest at pyridines, but in the case of the pyridinium salts, the protons chemical shifts at the central heterocycle are more shielded due to a peculiar anisotropy of the attached vinyl groups.

The Electron Effect of Aromatic Group: Control Conformation of 2-Aromatic Cyclododecanone Derivatives

2020 ◽  
Vol 24 (10) ◽  
pp. 1139-1147
Author(s):  
Yang Mingyan ◽  
Wang Daoquan ◽  
Wang Mingan
Keyword(s):  
1H Nmr ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
The Other ◽  
Repulsive Interaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Effect ◽  
Group Control

2-Phenylcyclododecanone and 2-cyclohexylcyclododecanone derivatives were synthesized and characterized by 1H NMR, 13C NMR, HR-ESI-MS and X-ray diffraction. Their preferred conformations were analyzed by the coupling constants in the 1H NMR spectra and X-ray diffraction, which showed the skeleton ring of these derivatives containing [3333]-2-one conformation, and the phenyl groups were located at the side-exo position of [3333]-2-one conformation due to the strong π-π repulsive interaction between the π- electron of benzene ring and π-electron of carbonyl group. The cyclohexyl groups were located at the corner-syn or the side-exo position of [3333]-2-one conformation depending on the hindrance of the other substituted groups. The π-π electron effect played a crucial role in efficiently controlling the preferred conformation of 2-aromatic cyclododecanone and the other 2-aromatic macrocyclic derivatives with the similar preferred square and rectangular conformations.

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