Formation of rhodium(III) carbonyls in nonaqueous solvents, and their decomposition by water to rhodium(I)

Abstract

Carbon monoxide reacts with dimethylacetamide solutions of RhCl₃,3H₂O under mild conditions to give initially a monocarbonyl complex of rhodium(III) in a bimolecular S_N2 reaction. This complex is slowly decomposed by the water present from the trihydrate to give the dichlorodicarbonylrhodate(I) species, [Rh(CO)₂Cl₂]^–. The study gives direct evidence for the role of water, or more likely hydroxide, in the reduction of metal ions by carbon monoxide.