Nuclear magnetic resonance studies of lanthanoid complexes. Part 3. Adducts of tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyloctane-3,5-dionato)praseodymium with bidentate amines

Abstract

Dynamic n.m.r. spectra have been obtained for adducts of the titie complex [Pr(fod)₃] with substituted ethylenediamines. Four exchange processes have been characterized or observed: (i) intermolecular exchange; (ii) ring opening; (iii) ring inversion; and (iv) intramolecular rearrangement(s) of the eight-co-ordinate complex. Barriers to ring inversion are reported. For the NN′-dimethylethylenediamine adduct, DL. and meso isomers are present in a 3.0 : 1 ratio.