Deuterium- induced 19F Isotope Shifts in Fluoroethenes
Deuterium‐induced 1 9F isotope shifts in the NMR spectra of 17 fluoroethenes are reported here together with other NMR parameters (1H and 1 9F chemical shifts and FF, HF, DF, and DH coupling constants). The two‐bond (g e m) and three‐bond (t r a n s) isotope shifts exhibit correlations with nuclear spin–spin coupling constants 2 J g e m (HF) and 3 J t r a n s (HF). The isotope shifts are interpreted using derivatives of nuclear shielding with respect to bond extension derived from the 1 9F temperature dependence at the zero‐pressure limit, and the changes in the mean bond lengths due to isotopic substitution. The latter are calculated using the previously reported Urey–Bradley force fields for these molecules. The analysis of the isotope shifts lead to estimates of the change of 1 9F nuclear shielding due to extension of a bond which is located at a g e m, c i s, or t r a n s position relative to the resonant nucleus. These 1 9F nuclear shielding derivatives correlate with the nuclear spin–spin coupling constants 2 J g e m (HF) , 3 J c i s (HF), and 3 J t r a n s (HF) which share the same pathway of electronic transmission.
Osten, H. J., Cynthia J. Jameson, and Norman C. Craig. 1985. "Deuterium- induced 19F Isotope Shifts in Fluoroethenes." The Journal of Chemical Physics 83(11): 5434-5441.
Journal of Chemical Physics
Chemistry and Biochemistry
Isotope shifts, Chemical bonds, Nuclear magnetic resonance, Chemical shifts, Nuclear resonance reactions