The Rare Examples of Thiosemicarbazonato Chromium(III) Complexes: Crystal Structures of [Cr(Hsal 4-Metsc)2]ClCH3OH and [Cr(Hsal 4-Phtsc)2]Cl

Reactions of salicylaldehyde 4-methylthiosemicarbazone (H2L1) and salicylaldehyde 4- phenylthiosemicarbazone (H2L2) with assorted chromium(III) precusors, [Cr(H2O)6]Cl3, [Cr(H2O)6](NO3)33H2O and [Cr(H2O)6](CH3COO)3, afforded new mononuclear chromium(III) complexes of the general formula [Cr(HL)2]X (X = Cl−, NO3 − and CH3COO−). In all isolated compounds, Cr(III) ion is coordinated by the O,N,S atoms of the two singly deprotonated thiosemicarbazonato ligands, which are present in the thione form. All complexes have been characterized in the solid-state by means of chemical analyses, TG analysis and IR spectroscopy. The crystal and molecular structures of [Cr(Hsal 4- Metsc)2]ClCH3OH and [Cr(Hsal 4-Phtsc)2]Cl have been determined on the basis of single-crystal X-ray diffraction data. In accordance with kinetic inertness of neutral chromium(III) complexes all our attempts to prepare thiosemicarbazonato complexes via ligand-exchange reaction with [Cr(acac)3] have been unsuccessful.( doi: 10.5562/cca2153

Supramolecular Isomerism of Coordination Compounds Based on the in Situ Formed [V2O3]4+ Core: Discrete and Chain-like Architectures

Flexible 1,5-bis(salicilydene)carbohydrazone ligand in combination with an in situ formed divanadium [V2O3]4+ core afforded one discrete tetranuclear complex and two polymeric chain-like architectures, mutually related as supramolecular isomers. The occurrence of a particular isomer was controlled through the reaction conditions. All isolated products were structurally characterized via X-ray diffraction and infrared spectroscopy, while the relative stability of the architectures was assessed via competitive slurry and thermal experiments. This study highlights the adaptability of oxovanadium species towards the coordination “inventory” of building blocks present in the environment, while at the same time it unveils the richness of assembly modes of the related structural units