Crystal Structures and Magnetic Properties of (2,2'-Dipyridyl)-(3-methoxysalicylaldiminato)copper(II) Perchlorate and (2,2'-Dipyridyl)-(4-methoxysalicylaldiminato)copper(II) Perchlorate

Abstract

The mixed-ligand dinuclear complexes (2,2'-dipyridyl)-(3-methoxysalicylaldiminato)copper( II) perchlorate (1) and (2,2'-dipyridyl)-(4-methoxysalicylaldiminato)copper(II) perchlorate (2)were synthesized and their crystal structures determined. Both structures consist of a dimeric unit involving a planar Cu 2 O 2 group. In both structures, the coordination sphere of the Cu atoms can be described as an elongated octahedron where the basal plane is formed by the twoN atoms of the 2,2'-dipyridyl molecule and the two O atoms of the salicylaldehyde anion. The phenoxo O atom is the negative ligand of the monomeric unit. Two apical Cu-O contacts complete the 4+2 coordination of the Cu atoms. They correspond to one of the O atoms of the perchlorate anion and to the O atom of the nearest salicylaldehyde molecule. Variable-temperature magnetic susceptibility data obey the Curie-Weiss law with Θ = -10.3(2) K for 1 and -10.1(2) K for 2. The decrease of the effective magnetic moment from 1.89(7) μB at 300 K to 1.77(7) μB at 70 K for 1 and from 1.88(8) μB at 300 K to 1.76(8) μB at 70 K for 2 and the negative Weiss constants indicate weak antiferromagnetic interactions between the two copper atoms in the dimeric units.