PREPARATION, PROPERTIES AND X-RAY STRUCTURE OF A CYCLIC COMPARTMENTALSCHIFF-BASE AND RELATED COMPLEXES CONTAINING D-METAL OR F-METAL IONS

A new compartmental ligand (H2LA) containing an N2O2 Schiff base and a n O2O4 'crown like' coordination site has been prepared by reaction of oxaoctane-1,8-diyldioxy)bis(2-hydroxybenzaldehyde) with ethylenediami ne and the [1 + 1] cyclic nature was confirmed by its X-ray single cry stal structural determination. When reacted with d- or f-metal ions, H 2LA forms mononuclear complexes where the metal ion coordinates respec tively the N2O2 or the O2O4 chamber. The X-ray structure of [La(H2LA)( H2O)(4)]Cl-3 shows the ten-coordination about the metal ion is reached by the six oxygen atoms of the compartmental ligand and by the oxygen atoms of four water molecules; the chloride atoms are ionic.