Synthesis, Supramolecular Self-Organization, and Thermal Behavior of Gold(III)–Thallium(III) Heteronuclear Complexes ([Au{S2CN(CH3)2}2][TlCl4])2 and ([Au{S2CN(C2H5)2}2][TlCl4])n

Abstract

The interaction of polymeric thallium(I) dimethyl- and diethyldithiocarbamates with [AuCl₄]^– in 2 M HCl has been studied. Heteropolynuclear complexes ([Au{S₂CN(CH₃)₂}₂][TlCl₄])₂ (I) and ([Au{S₂CN(C₂H₅)₂}₂][TlCl₄])_n (II) have been preparatively isolated from chemisorption systems [Tl₂{S₂CNR₂}2]_n–Au³⁺/2 M HCl (R = CH₃, C₂H₅). These compounds have been characterized by ¹³C CP/MAS NMR, and their crystal and supramolecular structures have been determined by X-ray crystallography. Basic structural units of compounds I and II are square-planar [Au{S₂CNR₂}₂]⁺ cations (with S,S'- bidentate coordination of two Dtc ligands to the gold atom) and distorted tetrahedral [TlCl4]–anions. In supramolecular self-organization, the decisive role is played by relatively weak secondary interactions Au⋯S and Au⋯Cl. With the use of simultaneous thermal analysis, the thermal behavior of I and II have been studied, which enabled the elucidation of temperature-induced transformations and identification of TlCl and reduced gold among the thermolysis products.