Revised structure for the γ-lactone derived from acid treatment of dihydroisopimaric acid

1976 ◽  
Vol 54 (3) ◽  
pp. 418-422 ◽  
Author(s):  
John W. ApSimon ◽  
Andrew M. Holmes ◽  
Helmut Beierbeck ◽  
John K. Saunders
Keyword(s):  
Acid Treatment ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Ring Fusion ◽  
Spin Lattice ◽  
Structure Revision ◽  
Chemical Shift Data ◽  
Shift Data ◽  
C Nmr

The γ-lactone obtained from acid treatment of dihydroisopimaric acid was found to have a cis-A/B ring fusion. This structure revision was based on 13C nmr chemical shift data and spin–lattice relaxation time (T1) measurements. Using the same methods, the δ-lactone derived from the same acid was shown to have the previously proposed structure.

Activation Energies for Fluxional Behavior in Aryl(pentachlorocyclopentadienyl)mercurials, η1 -C5Cl5 HgR, from 35Cl NQR Relaxation Times

1990 ◽  
Vol 45 (3-4) ◽  
pp. 503-510 ◽  
Author(s):  
Norbert Weiden ◽  
Alarich Weiss ◽  
Gary Wulfsberg ◽  
William Ilsley ◽  
William Ilsley ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Relaxation Times ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Activation Energies ◽  
Spin Lattice Relaxation ◽  
Spin Lattice ◽  
35Cl Nqr ◽  
C Nmr ◽  
Phenyl Mercury

Abstract Solid-state activation energies for fluxional behavior in three aryl-subsituted (pentachlorocyclo-pentadienyl)phenylmercury compounds RHgC5 Cl5 : (pentachlorocyclopentadienyl)(pentamethyl-phenyl)mercury (I, R = C6 (CH3)5 , Eact = 19.3 kJ mol-1); (pentachlorocyclopentadienyl)(2,4,6-tris-(terf-butyl)phenyl)mercury (II, R = 2,4,6-C 6 H 2 (C(CH3)3)3 , Eact = 59.5 kJ mol-1); and (pentachloro-cyclopentadienyl)(phenyl)mercury (III, R = C6H5 , E act = 62.8 kJ mol-1) have beeb obtained from 35Cl NQR spin-lattice relaxation-time measurements. II has also been shown to be fluxional in solution by 13C NMR spectra. II was prepared by an exchange reaction between Hg(C5Cl5)2 and Hg(2,4,6-C6H2(C(CH3)3)3)2 , which reacted readily despite the great steric hindrance present in the latter reagent.

Relative importance of the T-5 and T-7 terms in spin-lattice relaxation time

1979 ◽  
Vol 40 (12) ◽  
pp. 1179-1184 ◽  
Author(s):  
C. Blanchard ◽  
B. Gaillard ◽  
A. Deville
Keyword(s):  
Relaxation Time ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Relative Importance ◽  
Spin Lattice Relaxation Time ◽  
Spin Lattice

NUCLEAR SPIN-LATTICE RELAXATION TIME IN TIN

1978 ◽  
Vol 39 (C6) ◽  
pp. C6-1215-C6-1216
Author(s):  
H. Ahola ◽  
G.J. Ehnholm ◽  
S.T. Islander ◽  
B. Rantala
Keyword(s):  
Relaxation Time ◽  
Nuclear Spin ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Spin Lattice Relaxation Time ◽  
Spin Lattice ◽  
Nuclear Spin Lattice Relaxation

Protron spin-lattice relaxation time of duchenne dystrophy skeletal muscle by magnetic resonance imaging

1988 ◽  
Vol 11 (2) ◽  
pp. 97-102 ◽  
Author(s):  
Kiichiro Matsumura ◽  
Imaharu Nakano ◽  
Nobuo Fukuda ◽  
Hiroo Ikehira ◽  
Yukio Tateno ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Skeletal Muscle ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Resonance Imaging ◽  
Duchenne Dystrophy ◽  
Spin Lattice

Determination of chemical shift anisotropy tensor and molecular correlation time of proton pump inhibitor omeprazole by solid state NMR measurements

2020 ◽  
Vol 44 (44) ◽  
pp. 19393-19403
Author(s):  
Krishna Kishor Dey ◽  
Manasi Ghosh
Keyword(s):  
Correlation Time ◽  
Chemical Shift Anisotropy ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Spin Lattice ◽  
Structure And Dynamics ◽  
Molecular Correlation ◽  
Anisotropy Tensor

The correlation between the structure and dynamics of omeprazole is portrayed by extracting CSA parameters through the 13C 2DPASS CP-MAS SSNMR experiment, site specific spin–lattice relaxation time by Torchia CP experiment, and calculation of the molecular correlation time.

scholarly journals Tunneling Spectroscopy by Nuclear Magnetic Resonance: Analysis of Rotational Tunneling in Solid Pentamethylbenzene

1985 ◽  
Vol 40 (11) ◽  
pp. 1075-1084
Author(s):  
W. T. Sobol ◽  
K.R. Sridharan ◽  
I. G. Cameron ◽  
M. M. Pintar
Keyword(s):  
Frequency Dependence ◽  
Lattice Relaxation ◽  
Time Correlation ◽  
Lattice Relaxation Time ◽  
Polarization Transfer ◽  
Spin Lattice Relaxation ◽  
Transfer Model ◽  
Nuclear Magnetic Resonance Analysis ◽  
Spin Lattice ◽  
Resonance Analysis

The frequency dependence of the spin-lattice relaxation time T1 was measured at three temperatures near one of the Zeeman-tunneling level matching resonances for pentamethylbenzene. These measurements are correlated with 71 temperature dependence data from the literature. It is shown that the frequency dependence of the Zeeman-torsion coupling time cannot be explained in terms of the semiclassical perturbation theory using time correlation functions. A three bath polarization transfer model is also employed and the applicability of both models discussed. Zeeman-torsion coupling is further investigated using a saturation sequence and the results are compared with the predictions of the three bath polarization transfer model.

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