IrCl33H2O

IrCl3·3H2O, commonly written IrCl3(H2O)3, is a coordination compound of iridium in the +3 oxidation state. The neutral complex can be viewed as [Ir(H2O)3Cl3], an octahedral Ir(III) center bound to three water molecules and three chloride ligands. In such ML3L3 systems, fac- and mer- isomers are possible, and solid samples may consist of a mixture of arrangements depending on crystallization conditions.

Preparation and occurrence: The trihydrate is typically prepared by hydration of anhydrous IrCl3 or by crystallization from aqueous IrCl3 solutions. As a crystalline hydrate, it serves as a convenient iridium(III) chloride source for subsequent ligand substitution reactions in solution. In aqueous solution, ligand exchange can occur as aqua and chloride ligands are displaced by other donors.

Chemical properties and reactions: The aqua ligands in IrCl3(H2O)3 can be substituted by a range of ligands, enabling synthesis of diverse Ir(III) complexes. The chloride ligands can also participate in ligand redistribution under appropriate conditions. The compound is generally used as a starting material for preparing heteroleptic Ir(III) complexes, including those employed in catalysis and photoredox chemistry.

Applications: IrCl3(H2O)3 is a common precursor in inorganic synthesis for Ir(III) chemistry. It is used to prepare complexes with phosphines, polypyridines, and other ligands, and serves as a convenient entry point to catalysts and photochemical systems based on iridium.

Safety: Iridium compounds are relatively low in acute toxicity but should be handled with standard laboratory care. IrCl3(H2O)3 is a corrosive irritant to skin and eyes; use appropriate PPE, work in a fume hood, and follow institutional waste disposal procedures for inorganic salts.