NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY OF SOME SELENIUM COMPOUNDS

1965 ◽  
Vol 43 (6) ◽  
pp. 1672-1679 ◽  
Author(s):  
T. Birchall ◽  
R. J. Gillespie ◽  
S. L. Vekris
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Resonance Spectroscopy ◽  
Arsenic Trichloride ◽  
Selenium Compounds ◽  
Nuclear Magnetic Resonance Spectra ◽  
Tin Tetrachloride ◽  
Nuclear Magnetic

Selenium nuclear magnetic resonance spectra have been observed for a number of selenium compounds. Chemical shifts and coupling constants with hydrogen and fluorine have been obtained. Various systems involving selenium compounds have been studied. It was found that a mixture of SeOF2 and SeOCl2 contains SeOClF and that rapid selenium exchange occurs between SeOCl2 and SeOBr2 presumably via the intermediate SeOClBr. The reactions of selenium tetrahalides with sulfur and selenium trioxides and with boron trifluoride were studied. It was observed that antimony pentachloride, tin tetrachloride, arsenic trichloride, quinoline, and potassium chloride produce considerable shifts in the resonance of selenium oxychloride. These shifts can be interpreted in terms of the acid–base behavior of the solutes.

Studies of specifically fluorinated carbohydrates. Part II. Nuclear magnetic resonance studies of pentopyranosyl fluoride derivatives

1969 ◽  
Vol 47 (1) ◽  
pp. 19-30 ◽  
Author(s):  
L. D. Hall ◽  
J. F. Manville
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Resonance Spectroscopy ◽  
Magnetic Resonance Studies ◽  
Conformational Model ◽  
Nuclear Magnetic

Detailed studies, by 1H and 19F nuclear magnetic resonance spectroscopy, of a series of fully esterified pentopyranosyl fluorides, show that all such derivatives favor that conformer in which the fluorine substituent is axially oriented. This conclusion is supported by separate considerations of the vicinal and geminal19F–1H and 1H–1H coupling constants, of the long-range (4J) 1H–1H and 19F–1H coupling constants and of the 19F chemical shifts. The limitations of the above conformational model are discussed.

scholarly journals Carbon-13 nuclear magnetic resonance spectra of oxazoles

1979 ◽  
Vol 57 (23) ◽  
pp. 3168-3170 ◽  
Author(s):  
Henk Hiemstra ◽  
Hendrik A. Houwing ◽  
Okko Possel ◽  
Albert M. van Leusen
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Proton Coupling ◽  
Nuclear Magnetic Resonance Spectra ◽  
C Nmr ◽  
Magnetic Resonance Spectra ◽  
Nuclear Magnetic

The 13C nmr spectra of oxazole and eight mono- and disubstituted derivatives have been analyzed with regard to the chemical shifts and the various carbon–proton coupling constants of the ring carbons. The data of the parent oxazole are compared with thiazole and 1-methylimidazole.

13C nuclear magnetic resonance spectra of 3,6-disubstituted pyridazines

1991 ◽  
Vol 69 (6) ◽  
pp. 972-977 ◽  
Author(s):  
Gottfried Heinisch ◽  
Wolfgang Holzer
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Molecular Orbital Calculations ◽  
Nuclear Magnetic Resonance Spectra ◽  
13C Nuclear Magnetic Resonance ◽  
Magnetic Resonance Spectra ◽  
Nuclear Magnetic

The 13C nuclear magnetic resonance spectra of 17 3,6-disubstituted pyridazine derivatives have been systematically analyzed. Chemical shifts and various 13C, 1H coupling constants are reported. Attempts were made to correlate these data with results obtained from semiempirical molecular orbital calculations as well as with substituent electronegativities and Taft's substituent constants σI and σR0. Key words: 3,6-disubstituted pyridazines, 13C NMR spectroscopy, 13C, 1H spin coupling constants.

Nuclear Magnetic Resonance Studies on Fluorides of Trivalent Phosphorus

1965 ◽  
Vol 20 (2) ◽  
pp. 104-109 ◽  
Author(s):  
G. S. Reddy ◽  
R. Schmutzler
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Trivalent Phosphorus ◽  
Magnetic Resonance Studies ◽  
Regular Change ◽  
Nuclear Magnetic Resonance Spectra ◽  
Multiple Substitution ◽  
Nuclear Magnetic

The P31, F19, and H1 nuclear magnetic resonance spectra of a new series of compounds of the types (RO)nPF3-n and (R2N)nPF3-n (n = 1,2) have been studied. A regular change in the chemical shifts and coupling constants has been observed with multiple substitution. The changes in the coupling constants have been explained on the basis of the electronegativity of the atoms attached to phosphorus. Some long-range coupling constants between hydrogen and fluorine separated by five bonds were observed.

31P and 19F Nuclear Magnetic Resonance Studies of Phosphorus-Fluorine Compounds

1970 ◽  
Vol 25 (11) ◽  
pp. 1199-1214 ◽  
Author(s):  
G. S. Reddy ◽  
R. Schmutzler
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Coordination Number ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Magnetic Resonance Studies ◽  
Nuclear Magnetic Resonance Spectra ◽  
Fluorine Compounds ◽  
Nuclear Magnetic

The nuclear magnetic resonance spectra (31P, 19F) of a variety of compounds containing phosphorus-fluorine bonds have been studied, in continuation of earlier investigations on the same type of compounds.The previously observed relationship between coordination number of phosphorus and δP was generally confirmed, i. e. δP becomes more positive as the coordination number around phosphorus increases. No meaningful substitution rules, either for chemical shifts or for P-F coupling constants, could be established. The data obtained are discussed qualitatively in relation to the electronegativity of the substituents and to the coordination number of phosphorus. Data on the preparation and characterization of numerous phosphorus-fluorine compounds are also included.

scholarly journals Application of multiplet structure deconvolution to extract scalar coupling constants from 1D nuclear magnetic resonance spectra

2021 ◽  
Vol 2 (2) ◽  
pp. 545-555
Author(s):  
Damien Jeannerat ◽  
Carlos Cobas
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Scalar Coupling ◽  
Order Effects ◽  
Multiplet Structure ◽  
First Order ◽  
Nuclear Magnetic Resonance Spectra ◽  
Nuclear Magnetic

Abstract. Multiplet structure deconvolution provides a robust method to determine the values of the coupling constants in first-order 1D nuclear magnetic resonance (NMR) spectra. Functions simplifying the coupling structure for partners with spin larger than 1/2 and for doublets with unequal amplitudes were introduced. The chemical shifts of the coupling partners causing mild second-order effects can, in favourable cases, be calculated from the slopes measured in doublet structures. Illustrations demonstrate that deconvolution can straightforwardly analyse multiplet posing difficulties to humans and, in some cases, extract coupling constants from unresolved multiplets.

Aqueous solution interaction of the methylmercuric cation with the dinucleotides CpG and dCpdG as studied by carbon-13 nuclear magnetic resonance spectroscopy

1986 ◽  
Vol 64 (10) ◽  
pp. 2038-2041 ◽  
Author(s):  
G. W. Buchanan ◽  
M. J. Bell
Keyword(s):  
Aqueous Solution ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
The Self ◽  
Coupling Constants ◽  
Resonance Spectroscopy ◽  
Spectral Parameters ◽  
Guanine Base ◽  
Nuclear Magnetic

13C nuclear magnetic resonance chemical shifts and 13C–31P coupling constants are reported for the self-complementary dinucleotides CpG and dCpdG in aqueous solution. The influence of methylmercuration at pH 6.0 on these spectral parameters has been examined. Results are interpreted in terms of preferential methylmercuration at the N-7 site of the guanine base of each dinucleotide with concomitant base destacking.

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