Synthesis of a new bis(ferrocenyl)ruthenacyclopentatriene compound with a significant inter-metal electronic communication

A new 2,5-bis(ferrocenyl)ruthenacyclopentatriene complex was synthesized by the metallacycle formation reaction of RuBrCp-(cod) (Cp = eta (5)-C5H5) an d ethynylferrocene. Cyclic voltammetry of the complex showed a reversible o ne-electron reduction due to the ruthenacycle and a two-step one-electron o xidation of the ferrocenyl moieties. Separation of the redox potentials of the ferrocenyl moieties was 0.24 V, and the electronic spectrum of one-elec tron oxidized species exhibited an intervalence-transfer band at 1180 run. These results indicate the existence of significant electronic interactions between two ferrocenyl moieties through the ruthenacyclopentatriene ring. (C) 2001 Elsevier Science B.V. All rights reserved.