Heteroleptic Dithiocarbamato–Chlorido Gold(III) Complexes [Au(S2CNR2)Cl2] (R = CH3, iso-C3H7; R2 = (CH2)6): Synthesis, Supramolecular Structures, and Thermal Behavior

Resumo

The chemisorption binding of gold(III) by freshly precipitated binuclear zinc dithiocarbamates [Zn₂(S₂CNR₂)₄] from solutions in 2 M HCl makes it possible to obtain heteroligand complexes [Au(S₂CNR₂)Cl₂]: R = CH₃ (I), iso-C₃H₇ (II); R₂ = (CH₂)₆ (III). The structural organization of complexes I, II, and III is determined by X-ray diffraction analysis (CIF files CCDC no. 1813107, 1813369, and 1813108, respectively). The distorted square–planar structure of the cis-[AuS₂Cl₂] chromophores shows the low-spin dsp²-hybrid state of the central gold atom. Pairwise secondary interactions Au⋅⋅⋅S between the adjacent molecules in complexes I and III result in the building of zigzag polymer chains (⋅⋅⋅[Au{S₂CN(CH₃)₂}Cl₂]⋅⋅⋅)_n and binuclear aggregates [Au{S₂CN(CH₂)₆}Cl₂]₂ at the supramolecular level. Complex II is presented by discrete molecules [Au{S₂CN(iso-C₃H₇)₂}Cl₂]. According to the simultaneous thermal analysis data, the single final product of the thermolysis of compounds I–III is reduced elemental gold.