Synthesis and Structure of Heterometallic Clusters (IrCo₂, IrFe) Containing Bridging 1,2-Dicarba-closo-dodecaborane-1,2-dichalocogenolato Ligands

The 16-electron half-sandwich iridium complexes [Cp*Ir{E 2 C 2 (B 10 H 10 )}] [E = S ( 1a ), Se ( 1b )] (Cp* = η 5 -C 5 Me 5 ) [Cp*Ir[E 2 C 2 (B 10 H 10 )] = η 5 -pentamethylcyclopentadienyl-[1,2-dicarba- closo -dodecaborane(12)-dichalcogenolato]iridium] reacted with Co 2 (CO) 8 in toluene solution to afford the trinuclear clusters [Cp*Ir{E 2 C 2 (B 10 H 10 )}]{Co 2 (CO) 5 } [E = S ( 2a ), Se ( 2b )] and mononuclear complexes [Cp*Ir(CO){E 2 C 2 (B 10 H 10 )}] [E = S ( 3a ), Se ( 3b )] as byproducts. Compounds 2a and 2b contain closed IrCo 2 triangle geometry with one Co−Co and two Ir−Co bonds. The dinuclear IrFe complexes [Cp*Ir{E 2 C 2 (B 10 H 10 )}]{Fe(CO) 3 } [E = S ( 4a ), Se ( 4b )] were obtained from the reactions of 1a and 1b with Fe(CO) 5 in the presence of Me 3 NO. The molecular structures of 2a, 2b, and 4b have been determined by X-ray crystallography.