Nuclear magnetic resonance studies of lanthanoid complexes. Part 2. Adducts of tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyloctane-3,5-dion-ato)-praseodymium and -europium with unidentate secondary and tertiary amines

Abstract

Proton resonance spectra are reported far the title complexes [Pr(fod)₃] and [Eu(fod)₃] with a variety of secondary and tertiary amines. At low temperatures both substrate exchange and nitrogen inversion are slow on a proton-resonance time scale. Secondary amines form both 1 : 1 and 2 : 1 adducts; but tertiary amines give 1 : 1 adducts only. In the 2 : 1 adducts of NHMePrⁿ, meso and rac isomers, in approximately equal abundance, can be distinguished. In the 1 : 1 adduct of N-methylpiperidine with [Eu(fod)₃], axial and equatorial isomers are present in approximately equal amounts.