
TY  - JOUR
A1  - Contreras, RH 
A1  - Giribet, CG 
A1  - Natiello, MA 
A1  - Perez, J 
A1  - Rae, ID 
A1  - Weigold, JA 
T1  - Experimental and Theoretical-Study of Carbon-Fluorine Couplings in the NMR-Spectra of 2-Fluoroaryl Ketones
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1985
VL  - 38
IS  - 12
SP  - 1779
EP  - 1784
KW  - 
UR  - https://doi.org/10.1071/CH9851779 
N2  - Calculations by the IPPP-INDO method give the spin-spin coupling constants for the side-chain carbons, 3JCF and 4JCF, as 4.97 and 6.86 Hz respectively with substantial contributions to through-space coupling from the pathway CO-C-H&#8230;F. The observed values for 1-(2- fluorophenyl ) ethanone , 3.3 and 7.2 Hz, and for 1-(2,5- difluorophenyl ) ethanone , 3.7 and 7.3 Hz, are in good agreement with these predictions. Two compounds, a dihydroindenone and a naphthalenone, in which this pathway cannot be effective, show no fluorine coupling to the aliphatic carbon next to the carbonyl and the values of 3JCF are reduced to 2.2 and 2.5 Hz, consistent with the loss of a through-space Fermi contact term of the kind described above. 
ER  -

