Аннотация:The reactivity of [AreneRuCp]+ has been studied. It coincides in general with the reactivity of [AreneFeCp]+. The halogens (Cl, F) in the arene ligand of [HalC6H5RuCp]+ can be substituted smoothly by certain nucleophilic groups (PhS, HO, CN, CH3O, C5H10N). The [AreneRuCp]+ cations are capable of undergoing nucleophilic addition at the arene ligand by the action of NaBH4 or C6H5Li. As a result, unsubstituted and substituted cyclohexadienylcyclopentadienylruthenium complexes are formed (C6H7RuC5H5 and exo-C6H5C6H6RuC5H5, respectively). The [CH3C6H5RuC5H5]+ and [C6H5SC6H5RuC5H5]+ cations are transformed to [HOOCC6H5RuC5H5]+ and [C6H5SO2C6H5RuC5H5]+ by the action of KMnO4. The central ruthenium atom remains intact under these conditions. [AreneRuCp]+ cations fail to reduce to AreneRuCp under the reaction conditions used for the synthesis of AreneFeCp.