Synthesis and X-ray crystallographic studies of complexes involving H2acacen with early lanthanoids (H2acacen = N,N'-ethylenebis(acetylacetoneimine))

Abstract

The coordination properties of the Schiff base ligand N,N′-ethylenebis(acetylacetoneimine) (H2acacen), were investigated with a range of lanthanoid nitrate hexahydrate salts yielding [Ln(NO3)3(H2acacen)2][C6H12]n (Ln=La, Pr, Nd and Sm), and X-ray crystallographic characterisation revealed that the early lanthanoids all adopt the same polymeric structure with a single, bidentate H2acacen ligand attached to each metal centre and two monodentate H2acacen ligands bridging between successive metal centres resulting in a polymeric array. In a similar reaction, Yb(NO3)3·6H2O induced decomposition of H2acacen resulting in isolation of the new complex [Yb(H2O)2(NO3)2(μ-NO3)(acac)]2.