High resolution 119Sn nuclear magnetic resonance studies by pulse Fourier transform

1977 ◽  
Vol 55 (6) ◽  
pp. 927-931 ◽  
Author(s):  
C. R. Lassigne ◽  
E. J. Wells
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
High Resolution ◽  
Chemical Shift ◽  
Chemical Shifts ◽  
Relaxation Times ◽  
Spin Rotation ◽  
Tin Compounds ◽  
Magnetic Resonance Studies ◽  
Scalar Contribution

The T1's, linewidths (T2's), and chemical shifts of 119Sn nuclei in a variety of tin compounds have been surveyed using pulse Fourier transform techniques. The results span the very large chemical shift range for tin-119 (∼2000 ppm), and indicate rather short T1 values with widely varied T2 relaxation times. Possible mechanisms are discussed for both T1 and T2 relaxation times. Our results show an approximate correlation between T1 (119Sn) and the paramagnetic contribution to the observed shielding of the 119Sn nucleus, indicating that apart from a large scalar contribution in Sn(IV) iodides and bromides, the dominant 119Sn T1 mechanism is spin rotation interaction.

Carbon-13 Nuclear Magnetic Resonance Studies of Some Methyl Substituted Diphenylmethanes

1974 ◽  
Vol 52 (18) ◽  
pp. 3196-3200 ◽  
Author(s):  
Gerald W. Buchanan ◽  
Giorgio Montaudo ◽  
Paolo Finocchiaro
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Ring Current ◽  
Chemical Shifts ◽  
Magnetic Resonance Studies ◽  
Nuclear Magnetic

Carbon-13 n.m.r. chemical shifts are reported for diphenylmethane and nine methylated derivatives. Results are compared with those for related methylbenzenes. In the case of tri-ortho-substituted materials the predominance of a perpendicular conformation is suggested. Ring current calculations show that in contrast to the 1H chemical shift interpretations, the 13C shielding trends cannot originate primarily from anisotropic effects.

Carbon-13 nuclear magnetic resonance studies of organotellurium compounds. II. Chemical shift trends

1982 ◽  
Vol 60 (5) ◽  
pp. 596-600 ◽  
Author(s):  
Raj. K. Chadha ◽  
Jack M. Miller
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Chemical Shifts ◽  
Magnetic Resonance Studies ◽  
Nmr Chemical Shifts ◽  
Organic Group ◽  
Opposite Trend ◽  
Organotellurium Compounds ◽  
C Nmr

13C nmr chemical shifts are reported for some aromatic and aliphatic tellurium compounds. For a given organic group, the shift of the C1 atom varies in the order [Formula: see text], as expected from electronegative considerations. The C2 atom experiences an opposite trend while the C3 and C4 atoms of the ring experience smaller changes. The chemical shifts of para-substituted aromatic tellurium compounds do not show additivity of contributions from the substituents.

NOTIZEN: Use of 95Mo NMR for Identification of Molybdenum (VI) Chalcogenide Anions in Aqueous Solution

1977 ◽  
Vol 32 (5) ◽  
pp. 505-506 ◽  
Author(s):  
O. Lutz ◽  
A. Nolle ◽  
P. Kroneck
Keyword(s):  
Aqueous Solution ◽  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Magnetic Resonance ◽  
Aqueous Solutions ◽  
Chemical Shifts ◽  
Magnetic Resonance Studies ◽  
Nuclear Magnetic

Abstract95Mo Fourier transform nuclear magnetic resonance studies were made on aqueous solutions of oxo thiomolybdates. Chemical shifts up to 2200 ppm were found for the different unambiguously assigned species MoO4-nSn2- (n = 0, 1, 2, 3, 4).

Nuclear Magnetic Resonance Studies of Solute–Solvent Interactions. Improved Methods of Proton Chemical Shift Determinations for Completely Associated and Unassociated Solutes

1973 ◽  
Vol 51 (5) ◽  
pp. 787-791 ◽  
Author(s):  
R. E. Klinck
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Chemical Shifts ◽  
Solvent Ratio ◽  
Proton Chemical Shift ◽  
Solvent Interactions ◽  
Magnetic Resonance Studies ◽  
Improved Methods ◽  
Proton Chemical Shifts

Previous data for the temperature dependence of the proton chemical shifts of two para-substituted benzaldehydes in toluene solution are re-investigated using improved methods for obtaining the proton chemical shifts in the associated and unassociated solutes. The calculations provide ΔH and ΔS values of −1.13 ± 0.07 kcal/mol and −4.0 ± 0.3 e.u., respectively. Attempts to determine the solute–solvent ratio gave inconclusive results.

scholarly journals Fourier Transform NM R Investigations of 77Se in Aqueous Solutions

1978 ◽  
Vol 33 (9) ◽  
pp. 1025-1028 ◽  
Author(s):  
W. Koch ◽  
O. Lutz ◽  
A. Nolle
Keyword(s):  
Fourier Transform ◽  
High Resolution ◽  
Aqueous Solutions ◽  
Magnetic Moment ◽  
Infinite Dilution ◽  
Chemical Shifts ◽  
Relaxation Times ◽  
Recovery Method ◽  
A Value ◽  
Nmr Signals

In solutions of H2SeO3, Na2SeO3 , NaHSeO3 and Na2SeO4 in H2O NMR signals of 77Se have been observed. In these solutions chemical shifts were determined. In a 4 molal solution of Na2SeO3 the ratio of Larmor frequencies υ(77Se)/υ(1H) has been measured with a high-resolution probe. A value of the magnetic moment of 77Se in Na2SeO3 at infinite dilution in H2O is given: |μ(77Se)| = 0.533 299 6(7)μN. Relaxation times T1 have been measured by the inversion-recovery method. In a 4 molal solution of Na2SeO3 in H2O a NOE enhancement of 0.4(1) could be observed.

Metabolites of bird's nest fungi. Part 10. Carbon-13 nuclear magnetic resonance studies on the cyathins

1978 ◽  
Vol 56 (16) ◽  
pp. 2197-2199 ◽  
Author(s):  
William A. Ayer ◽  
Thomas T. Nakashima ◽  
Dale E. Ward
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Chemical Shifts ◽  
Magnetic Resonance Studies ◽  
Chemical Shift Data ◽  
Related Compounds ◽  
Shift Data ◽  
Methyl Acetal ◽  
Magnetic Resonance Spectra

The carbon-13 magnetic resonance spectra of cyathin A3 and several related compounds have been measured and the chemical shifts have been assigned. The chemical shift data have been used to determine the stereochemistry at C-1 in cyafrin A4 and to determine the position of the bromine in 1-bromoallocyathin A3 methyl acetal.

The High Resolution NMR Spectra of Pesticides. II. The DDT-Type Compounds

1969 ◽  
Vol 52 (5) ◽  
pp. 1074-1092 ◽  
Author(s):  
L H Keith ◽  
A L Alford ◽  
A W Garrison
Keyword(s):  
Nuclear Magnetic Resonance ◽  
High Resolution ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Aromatic Rings ◽  
Nuclear Magnetic Resonance Spectra ◽  
High Resolution Nmr ◽  
Related Compounds ◽  
Deshielding Effect

Abstract The high resolution nuclear magnetic resonance spectra of the DDT class of pesticides and related compounds are discussed, including a study of the resonances of the aromatic protons as they are affected by various substiluents. The CCl3 moiety on the α-carbon strongly deshields the ortho protons on the aromatic rings, and this deshielding effect is greatly enhanced by substitution of a chlorine ortho rather than para on the aromatic ring. These deshielding effects are explained by a consideration of the electronegativity of the substituents and the stereochemistry of the molecule. The chemical shifts and coupling constants are tabulated.

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