Etude par la résonance de l'azote 15 et du phosphore 31 de la liaison P—N dans des dérivés du phosphore trivalent; analyse statistique des données expérimentales

Abstract

Natural abundance 15N and 31P nmr and dynamic 13C nmr have been applied to the study of about fifty aminophosphines, in order to generalize the influence of the chemical factors which govern the electronic distribution of the nitrogen–phosphorus III bond. Factor and regression analyses of δ15N, δ31P, and 1JP—N values performed on different series of aminophosphines have shown that common factors and various correlations exist between the nmr parameters in the different kinds of derivatives. The statistical results are discussed in terms of topologic, electronic, and steric contributions. The nature of the different substituents of the nitrogen or phosphorus atoms governs the observed changes in screening, coupling constants, and the rotational barriers ΔG≠ around the P—N bond, which are explained in considering the type of nitrogen and phosphorus hybridization, the pπ–dπ donation and the electronic states (ΔE−1 approximation) of the P—N fragment.