MAGNETIC-PROPERTIES AND CRYSTAL-STRUCTURES OF BINUCLEAR COPPER(II) COMPLEXES WITH HETEROCYCLIC THIONE DONORS OF 1,3-BIS(HYDROXYMETHYL)-2-IMIDAZOLIDINETHIONE AND 1-HYDROXYMETHYL-3-METHYL-2-IMIDAZOLIDINETHIONE

A new series of binuclear copper(II) complexes with 1,3-bis(hydroxymet hyl)-2-imidazolidinethione, [Cu-(RCOO)(HL(1))](2) (where R=CH3 (1), C6 H5 (2), 2-CH3C6H4 (3), 4-CH3C6H4 (4), 2-ClC6H4 (5), and 2-Br6C6H4 (6)) , and with 1-hydroxymethyl-3-methyl-2-imidazolidinethione, [Cu(RCOO)(L (2))](2) (where R=CH3 (7), 2-CH3C6H4 (8), and 4-CH3C6H4 (9)), have bee n prepared. The magnetic susceptibility data of complexes 1-9 conform to the usual dimer equation with the -2J values ranging from 227 to 99 2 cm(-1). Crystal structure analyses of 3, 4, 7, and 9 revealed that t wo copper atoms are linked by two alkoxo-bridges with separations of 3 .015(3)-3.069(3) Angstrom in each complex. The coordination around eac h copper atom of the complexes is essentially a square planar configur ation with one sulfur and two alkoxo-oxygen atoms of HL(1) or L(2) and one oxygen atom of carboxylates. Each alkoxo-group asymmetrically bri dges with the Cu1-O1 bonds (1.90-1.92 Angstrom), which are shorter tha n the Cu1'-O1 bonds (1.93-1.97 Angstrom). The -2J values for complexes 3, 4, 7, and 9 are much better correlated with the Cu1'-O1 bond dista nces than with the allcoxo-bridging Cu1-O1-Cu1' angles.