Lanthanide-induced shifts in proton nuclear magnetic resonance spectra. II. Lanthanide-induced changes in proton spin-spin coupling constants

1972 ◽  
Vol 94 (12) ◽  
pp. 4381-4382 ◽  
Author(s):  
B. L. Shapiro ◽  
Milton D. Johnston ◽  
Robert L. R. Towns

An analysis has been made of the high-resolution nuclear-magnetic-resonance spectrum given by the hydrogen nuclei of 2:3-dichloropropene-l and cisand trans 1:3-dichloropropene-1. The spectra at 40 Mc/s of the 1:3-dichloropropenes were analyzed by means of the theory for ABX 2 developed here; the 16·2 Mc/s spectra were analyzed according to the ABC 2 theory by means of a digital computer. It is concluded that the ‘long-range’ spin-spin coupling constants between hydrogen nuclei on carbon atoms 1 and 3 of the 1 : 3-dichloropropenes are of opposite sign to the remainder. A correlation of these results with earlier work on butene-1 by Alexander (1958) leads to analogous conclusions for this molecule also.



1996 ◽  
Vol 74 (8) ◽  
pp. 1524-1525 ◽  
Author(s):  
Ted Schaefer ◽  
Guy M. Bernard ◽  
Frank E. Hruska

An excellent linear correlation (r = 0.9999) exists between the spin–spin coupling constants 1J(1H,13C), in benzene dissolved in four solvents (R. Laatikainen et al. J. Am. Chem. Soc. 117, 11006 (1995)) and Ando's solvation dielectric function, ε/(ε – 1). The solvents are cyclohexane, carbon disulfide, pyridine, and acetone. 1J(1H,13C)for gaseous benzene is predicted to be 156.99(2) Hz at 300 K. Key words: spin–spin coupling constants, 1J(1H,13C) for benzene in the vapor phase; spin–spin coupling constants, solvent dielectric constant dependence of 1J(1H,13C) in benzene; benzene, estimate of 1J(1H,13C) in the vapor; nuclear magnetic resonance, estimate of 1J(1H,13C) in gaseous benzene.



1957 ◽  
Vol 35 (12) ◽  
pp. 1487-1495 ◽  
Author(s):  
W. G. Schneider ◽  
H. J. Bernstein ◽  
J. A. Pople

The proton resonance spectra of pyridine, 2,6-pyridine-d2, 3-pyridine-d1, and 4-pyridine-d1 have been obtained for the pure liquids under conditions of high resolution. The spectra have been analyzed as proton groupings of AB2X2, AB2, perturbed ABX, and B2X2 respectively. The spin-coupling constants obtained from analysis of the simpler spectra of the deuterated molecules were used to suggest trial solutions for the analysis of the complicated AB2X2 spectrum of pyridine. A final set of chemical shifts and spin-coupling constants derived for pyridine give satisfactory agreement between the observed and calculated spectrum.



1978 ◽  
Vol 56 (16) ◽  
pp. 2129-2133 ◽  
Author(s):  
Alan Wilmot Douglas

Carbon-13 nuclear magnetic resonance spectra have been obtained and fully assignee for a number of 2-methyl-1-{[p-(methylthio) or -(methylsulfinyl}phenyl]methylene}-1H-indene-3- acetic acid derivatives, including the potent anti-inflammatory compound sulindac, 1Z. Paired E and Z isomers were studied along with the sulindac sodium salt and ethyl ester in the Z series. Variations in steric crowding in E vs. Z isomers produce chemical shift effects which alternate with the number of intervening bonds. Fluorine substituent effects and 19F nuclear spin coupling to 13C nuclei, second-order features in off-resonance proton-decoupled spectra, and values of long-range 13CH nuclear spin coupling constants have been employed in making a complete set of assignments.



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