Interaction entre les réactifs lanthanidiques et les bases de Lewis: Application à l'analyse conformationnelle d'alcools cyclohexaniques

Abstract

A method for the determination of the intrinsic parameters K and Δ for lanthanide–substrate complexes has been extended to conformationally mobile molecules. These parameters, determined for a series of secondary cyclohexane alcohols (cyclohexanol and 2-methylcyclohexanol) and for tertiary alcohols (1-methylcyclohexanol and 1-ethylcyclohexanol) complexed with Eu(DPM)3 and Yb(DPM)3 lead to the determination of the conformational equilibrium constants between) the free species on one part and the complexed species on the other.The results obtained for the free species are in good agreement with those obtained by other physicochemical methods. For the complexed species an appreciable shift of conformational equilibrium is noted for low values of the association constants.For the first time, the tert-butyl group of Yb(DPM)3 has been used as a conformational probe. [Journal translation]