Synthesis of hetero-substituted derivatives of cobalt bis(1,2-dicarbollide)

A new approach to synthesis of hetero-substituted derivatives of cobalt bis(1,2-dicarbollide) was proposed. The approach involves stepwise introduction of functional groups into different dicarbollide ligands. Halogenation of the monohydroxy derivative [8-OH-3,3′-Co-(1,2-C2B9H10)(1′,2′-C2B9H11)]− gave the corresponding halogen hydroxy derivatives [8-OH-8′-X-3,3′-Co(1,2-C2B9H10)2]− (X = Cl, Br, and I). Reactions of 8,8′-μ-iodonium-3-commo-cobaltbis(1,2-dicarba-closo-dodecaborate) [8,8′-I-3,3′-Co(1,2-C2B9H10)2] with chloroform and 1,2-dibromoethane yielded the mixed halides [8-Y-8′-I-3,3′-Co(1,2-C2B9H10)2]− (Y = Cl and Br).