Synthesis and Structural Study of the Mixed Copper (II)/lanthanum (III) Complex with the Bicompartmental Ligand H2L = 2,2'-{propane-1,2-diyl bis[Nitrilomethylylidene ]}Bis(6-Methoxyphenol)

Abstract

The neutral hetero-trinuclear compound 3d-4f, [Cu(II)La(III)Cu(II)] was obtained with the “brick by brick” method and it crystallizes in the monoclinic system with a space group of P2/n. The asymmetric unit of the structure of [Cu2(μ-L2)La(NO3)2] contains two molecules of the dideprotonated ligand L2-, two Cu(II) ions, one La(III) ion and two bidentate nitrate anions. In the structure of the trinuclear complex, the two Cu(II) ions and the La(III) ion are bridged by two phenolate oxygen atoms. The Cu(II) ion has a square planar geometry with the basal plane formed by two imine nitrogen atoms and two phenolic oxygen atoms. The La(III) ion, which occupies the largest open site of the Schiff base ligand, is bonded to two phenolate oxygen atoms and two methoxy oxygen atoms of the ligand and two oxygen atoms of a bidentate nitrate group from each ligand. The La(III) cation is located in the planar cavity defined by the two phenolate oxygen atoms and the two methoxy oxygen atoms. The positive charge of Cu(II) and La(III) ions is balanced by the deprotonated L2- ligand, perchlorata and nitrate anions. The duodecacoordinated La(III) ion coordination polyhedron is described as a severely distorted icosahedron or dodecahedron.