Study of stereochemical dependences of the direct 13C-1H spin-spin coupling constants in vinil pyridines by the Quantum Chemical INDO-RPA method.

AFONIN, A. V.; NELIDA MARIA PERUCHENA; SOSA, G. L.; CONTRERAS, R. H.

Russian Chemical Bulletin

SPRINGER

Año: 1997 vol. V. p. 251 - 253

1066-5285

The stereochemical dependences of the direct13C−1H spin-spin coupling constants (SSCC) in the vinyl group of vinylpyridines studied by the quantum-chemical INDO-RPA method indicate that the steric closeness of the hydrogen atom to the nitrogen atom causes an increase in the corresponding direct13C−1H SSCC and a decrease in the analogous constant of the geminal hydrogen atom. The results obtained qualitatively agree with the data of ab initio calculations for the simplest systems and the experiment. At the same time, an essential quantitative overestimation of the real effect takes place.