44ª Reunião Anual Virtual da SBQ

Xanthates are compounds of great interest in coordination chemistry due to the presence of the OS2 group in their structure, which establishes different forms of coordination with the metallic center. In addition, this class has applicability in the biological, environmental and technological areas. In this work, thermochemical, NBO and EDA analyzes of zinc complexes C1-C4 with propyl (L1), butyl (L2), amyl (L3) and 2-ethoxyethylxanthates (L4) were performed. The density functional theory through the M06L method was used associated with the base functions 6-311++ G ** for the atoms of S, C, O and H and LANL2TZ with pseudopotential for zinc. The thermochemistry was analyzed for the zinc complexes from the first and second substitution of water molecules by the xanthate ligands. Furthermore, the complexes were analyzed in their bidentate form and also for their cis/trans isomerism. It is possible to observe an increase in stability, which is proportional to the increase in the chain from L1 to L3. This trend can be explained by the better neutralization of the metal’s dicathionic charge through the increase in the electron density in the sulfur atom, from the carbon chain donor atoms. Besides, the M-S bond occurs through density donation from the sulfur p character orbital and density reception by the zinc s orbital. The data obtained in this study confirm that xanthate complexes can have different coordination spheres. The complexes trans-C1-C4 have M-L bond predominantly ionic.