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 (H2L) and salicylaldehyde 4phenylthiosemicarbazone (H2L) with assorted chromium(III) precusors, [Cr(H2O)6]Cl3, [Cr(H2O)6](NO3)33H2O 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 4Metsc)2]ClCH3OH 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)