13C RMN: Non-équivalences d'ammoniums quaternaires diastéréoisoméres

¹³C magnetic resonance spectra of six diastereomeric mixtures of quaternary ammonium salts were investigated. Assignment of the signals of the non-aromatic carbons and measurement of the non-equivalences allowed the determination of the ratio of isomers in the mixtures. A deshielding β effect and a shielding γ effect for the quaternisation were pointed out.