Abstract

Studies on the Coordination Compounds of Thiazolidin-4-one Derived from Salicylaldehyde-o-Hydroxyphenylurea

Author(s): D. Kumar, V. Pandey and Anju Gupta

An equimolar mixture of salicylaldehyde and o-hydrxyphenylurea upon refluxing in MeOH forms the Schiff base (1). The latter upon reacting with HSCH2COOH in dry C6H6 undergoes cycloaddition reaction and forms the corresponding thiazolidin-4-one, LH3 (2). A MeOH solution of 2 reacts with Cu (II), Co (II), Ni (II), MoO2 (VI) and Zr (OH)2 (IV) ions and forms the monomeric, nonelectrolyte coordination compounds, [Cu(OAc)(LH2)] (3), [M(OAc)(LH2)(MeOH)2] (4) (here M = Co, Ni), [MoO2(acac)(LH2)(MeOH)] (5) and [Zr(OH)3(LH2)] (6). A THF solution of a bidentate ON or NN donor ligand (AA) like ethanolamine (ea), o-aminophenol (oap), ethylenediamine (en), o-phenylenediamine (phen), 2,2'-bipyridyl (bipy) and 1,10-phenanthroline (ophen) reacts with a THF solution of (6) and forms the heterochelate, [Zr(OH)3(LH2)(AA)] (7). The coordination compounds have been characterized on the basis of elemental analyses, molecular weight, molar conductance, spectral (IR, reflectance, NMR) studies and magnetic susceptibility measurements. (2) behaves as a monobasic tridentate ONO donor ligand in these coordination compounds. A square-planar structure for (3), an octahedral structure for (4) (M = Co, Ni) and (6), and an eight-coordinate structure for (5) and (7) are suggested.