Reaction of dimethylthallium(III) acetate and isatin-3-thiosemicarbazone. Crystal and molecular structure of dimethyl(dimethylsulfoxide)(isatin-3-thiosemicarbazonato)thallium(III)

The reaction of dimethylthallium(III) acetate and isatin-3-thiosemicarbazone (HisaTSC) afforded [TlMe2(isaTSC)], which recrystallised from DMSO as [TlMe2(isaTSC)(DMSO)]. In this crystal the Tl atom is bound to the S, N(3) and O atoms of an N(2)-deprotonated thiosemicarbazone ligand, to the O of a DMSO molecule, and to the two methyl C atoms. An additional Tl⋯OisaTSC interaction with a neighbouring molecule gives rise to a weakly bonded dimer in which the thallium atoms have distorted pentagonal bipyramidal environments. The changes induced in the solid-state IR spectrum of the free ligand by deprotonation and coordination are analysed and the 1H, 13C and 15N NMR spectra are also discussed.