Chemical Evolution in Solutions of Ir Complex [H(dmso)₂]₂[IrCl₆]. Structures of [H(dmso)₂]₂[IrCl₆], [H(dmso)][IrCl₄(dmso)₂], [Me₂SCH₂C(O)Me][IrCl₄(dmso)₂], [Me₂SCH₂C(O)Me]₂[IrCl₆] and Its Os Analogue

Abstract

An iridium complex [H(dmso)2]2[IrCl6] (1) is synthesized via the reaction of H2IrCl6 with DMSO in an acetone solution. The substance is thoroughly characterized using UV‐Vis, ATR‐FTIR, NMR, and EPR spectroscopies, single‐crystal and powder X‐ray diffraction. Iridium undergoes a slow spontaneous reduction to the chemical state +3 when solutions of 1 in water, hydrochloric acid, or acetone (CIr=n ⋅ 10−2−n ⋅ 10−4 M) are allowed to age in ambience. In the case of acetone solutions, the reduction is accompanied by the incorporation of DMSO molecules into the coordination sphere of Ir giving rise to trans‐[IrIIICl4(dmso)2]−. In parallel, protonated DMSO shows reactivity towards acetone to afford dimethylacetonylsulfonium cations. Red crystals of [Me2SCH2C(O)Me]2[IrCl6] (2), orange crystals of [Me2SCH2C(O)Me][IrCl4(dmso)2] (3), and yellow crystals of [H(dmso)][IrCl4(dmso)2] (4) were isolated from aged acetone solutions of 1 and studied by X‐ray crystallography. In the crystal structures of 2 and 3, dimethylacetonylsulfonium act as the cationic parts of the complexes. Meanwhile, the protonated form of DMSO, hydroxy(dimethyl)sulfonium, is found in 4. A similar aging procedure applied to an acetone solution of Os‐based analogue [H(dmso)2]2[OsCl6] afforded a novel osmium complex [Me2SCH2C(O)Me]2[OsCl6] (5), which was proven to be isostructural to 2.

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]

“…Recently, we have reported the crystal structure of the compound [H­(dmso)]­[Ir III Cl 4 (dmso-κS) 2 ] corresponding to the space group Ama 2. In that structure, the hydrogen atom of the OH group forms a hydrogen bond with Cl ligands of the anion . Thus, we describe herewith a novel polymorph modification of [H­(dmso)]­[ trans- Ir III Cl 4 (dmso-κS) 2 ].…”

“…In that structure, the hydrogen atom of the OH group forms a hydrogen bond with Cl ligands of the anion. 29 Thus, we describe herewith a novel polymorph modification of [H(dmso)][ trans- Ir III Cl 4 (dmso-κS) 2 ].…”