Novel Group 9 Metal Complexes Containing an S,S'-Chelating o-Carboranyl Ligand System: Synthesis, Crystal Structures, and Electrochemical Properties of Dinuclear [{(cod)M}₂(S,S'-S₂C₂B₁₀H₁₀)] (cod = 1,5-cyclooctadiene;M = Rh OR Ir)] and Mononclear Cp^*CoI[S,S'-S(S=PMe2)C₂B₁₀H₁₀] Metal Complexs

Abstract

The synthesis of novel group 9 metal complexes containing the S,S'-chelate ligands, Li 2 S 2 C 2 B 10 H 10 (2a) and LiS(S=PMe 2 )C 2 B 10 H 10 (2b), is described. Two new dinuclear complexes of the type [{(cod)M} 2 (S,S'-S 2 C 2 B 10 H 10 )] (cod = 1,5-cyclooctadiene; M = Rh (3a), or Ir (3b)) were synthesized by the reaction of chloridebridged dimers [M(µ-Cl)(cod)] 2 with one molar equivalent of the corresponding dilithium dithiolato ligand Li 2 S 2 C 2 B 10 H 10 (2a). X-ray crystal structure analysis of 3a revealed a dinuclear structure in which each (cod)Rh unit is attached to a distinct sulfur atom of a 1,2-dithio-o-carboranyl ligand (2a). Additionally, the electrochemical properties of 3a and 3b were investigated by cyclic voltammetry. In an analogous manner, reaction of the lithium dithiolato ligand LiS(S=PMe 2 )C 2 B 10 H 10 (2b) with Cp*CoI 2 (CO) produced a mononuclear dithiolato complex, [Cp*CoI{(S,S'-S(S=PMe 2 )C 2 B 10 H 10 )}] (4), which was characterized by single-crystal X-ray analysis.