13C NMR investigations of phenol–triethylamine complexes: Influence of hydrogen bond interaction on the electronic structure of the aliphatic chain

Abstract

AbstractThe influence of hydrogen bond formation on 13C chemical shifts at the α and β positions of triethylamine and tri‐n‐butylamine has been investigated by dipole moment measurements and CNDO/2 calculations. It has been shown that a hydrogen bridge dipole moment occurs during complexation. Moreover, the change observed in the C‐αC‐β bond dipole moment is proportional to the hydrogen bridge dipole moment, but is approximately 100 times smaller. This change has been related to differences between the 13C chemical shifts at the α and β positions of amines.