New chloride-dimethylsulfoxide-iridium(III) complex with histaminium

First Iridium(IV) Chloride-Dimethyl Sulfoxide Complex [H(dmso)2][IrCl5(dmso-κO)]: Synthesis and Structure along with Novel Polymorph Modifications of [H(dmso)2][trans-IrCl4(dmso-κS)2] and [H(dmso)][trans-IrCl4(dmso-κS)2]

As evidenced by UV-Vis and EPR spectroscopies, the reaction of H₂IrCl₆·6H₂O or Na₂[IrCl₆]·nH₂O with DMSO results in a slow reduction of Ir(IV) avoiding the formation of Ir(IV) dimethyl sulfoxide complexes in measurable quantities. More specifically, we successfully isolated and solved the crystal structure of a sodium hexachloridoiridate(III), Na₃[IrCl₆]·2H₂O, as a product of Na₂[IrCl₆]·nH₂O reduction in an acetone solution. Furthermore, it was shown that [IrCl₅(Me₂CO)]^- species is gradually formed in an acetone solution of H₂IrCl₆·6H₂O upon storage. The reaction of DMSO with aged acetone solution of H₂IrCl₆·6H₂O dominated by [IrCl₅(Me₂CO)]^- affords a novel iridium(IV) chloride-dimethyl sulfoxide salt [H(dmso)₂][IrCl₅(dmso-κO)] (1). The compound was characterized by various spectroscopies (IR, EPR, UV-Vis) and X-ray diffraction techniques applied both to single-crystal and polycrystalline powder. The DMSO ligand is coordinated to the iridium site via the oxygen atom. New polymorph modifications of known iridium(III) complexes [H(dmso)₂][trans-IrCl₄(dmso-κS)₂] and [H(dmso)][trans-IrCl₄(dmso-κS)₂] were isolated and structurally elucidated as byproducts of the above reaction.

Synthesis, X-ray characterization, DFT calculations and Hirshfeld surface analysis of thiosemicarbazone complexes of Mn+ ions (n = 2, 3; M = Ni, Cd, Mn, Co and Cu)

Herein we report the synthesis, X-ray characterization, DFT calculations and Hirshfeld surface analysis of seven complexes of transition metal ions with pyridine-based thiosemicarbazone ligands.