RhCl33H2O

RhCl3·3H2O, also written RhCl3(H2O)3, is rhodium(III) chloride trihydrate. It is an inorganic compound commonly used as a versatile precursor for the preparation of rhodium coordination complexes. In solid form, the compound is typically described as the octahedral complex [Rh(H2O)3Cl3], with three chloride ligands and three aqua ligands bound to a Rh(III) center.

Preparation and occurrence: RhCl3·3H2O is usually obtained by crystallization from aqueous solutions of rhodium(III) chloride or by hydrolysis of RhCl3 in water under controlled conditions. It is a stable, water-containing salt that can be handled as a solid or dissolved in water.

Structure and reactivity: The rhodium center in RhCl3·3H2O is six-coordinate and achieves an octahedral geometry. The compound readily undergoes ligand substitution, allowing the three water ligands (aqua) to be replaced by a variety of neutral or anionic ligands to form a wide range of rhodium(III) complexes. Upon strong heating or certain chemical treatments, it can lose water ligands and participate in further transformations, including reduction to other oxidation states under appropriate conditions.

Uses: As a common starting material in inorganic and organometallic synthesis, RhCl3·3H2O is employed to prepare diverse rhodium(III) complexes used in catalysis and materials chemistry. It serves as a convenient source of Rh(III) for ligand substitution reactions and for generating catalysts after appropriate modification with ligands or reducing agents.

Safety: Rhodium salts can be irritants and should be handled with standard laboratory safety practices, including gloves and eye protection, in a well-ventilated area. Avoid ingestion, inhalation, and contact with skin.