Transition metal complexes with the thiosemicarbazide-based ligands—I. Nickel(II) complexes with the quadridentate ligands based on S-methylisothiosemicarbazide; X-ray crystal structure of (acetyl-acetone N(1)-salicylidene-S-methylizothiosemicarbazonato) nickel(II)

Abstract

The reaction of a warm ethanolic solution of [Ni(SALSMeTSC-H)Py]Cl·0.5Py (SALSMeTSC = salicylaldehyde S-methylisothiosemicarbazone) with salicylaldehyde and acetylacetone (HACAC), yielded the corresponding square-planar complexes [Ni(SAL 2SMeTSC-2H)] ( A) and [Ni(SALACACSMeTSC-2H)] ( B) (SAL 2SMeTSC, and SALACACSMeTSC = quadridentate 2O2N ligand: N(1),N(3)- bis(salicylidene)-S-methylisothiosemicarbazide, and acetylacetone N(1)-salicylidene-S-methylisothiosemicarbazone, respectively). An X-ray analysis of complex B showed that in the reaction of the starting complex with HACAC a rearrangement of the salicylaldehyde moiety takes place (while the CN(3) bond of the azomethine group is ruptured) and its binding to the N(1) nitrogen. At the same time, HACAC is simultaneously bonded to the liberated N(3)-nitrogen of the hydrazine fragment. Crystal data for the complex B (NiC 14H 15N 3O 2S) are: M r = 348.0, orthorhombic, space group Pna2 1, a = 7.484(3), b = 21.995(8), c = 8.866(3) Å; V = 1459.44 Å 3, Z = 4, F(000) = 720, Dc = 1.58 g cm −1, Do = 1.56 g cm −1, μ(MoKα) = 14.45 cm −1. The structure was solved by the heavy-atom method and refined anisotropically to an R value of 0.078 for 1174 non-zero reflections. The complex molecules are planar, the NiNi distance of nearest molecules being about 3.76 Å. The compounds have been characterized by elemental analysis as well as by IR and electronic spectra.