STRUCTURAL CHARACTERIZATION AND ELECTROCHEMICAL STUDY OF NOVEL FERROCENE DERIVATIVES PREPARED FROM [(BETA-FERROCENYLVINYL)IMINO]PHOSPHORANEBY AZA-WITTIG REACTIONS

A rapid and efficient synthetic procedure has been developed to prepar e new ferrocene derivatives such as beta-ferrocenylvinyl heterocumulen es and ferrocene-containing imidazole ring bearing one, two, or three ferrocene subunits. The method is based on the aza Wittig re action of [(beta-ferrocenylvinyl)imino]phosphorane 3, readily available from fe rrocenecarboxaldehyde by sequential treatment with ethyl azidoacetate and triphenylphosphine, with isocyanates and further treatment with th e appropriate primary amine. The crystal structures of compounds 6c (m onoferrocene derivative), 11c, and 12b (biferrocene derivatives) have been determined by single-crystal X-ray methods. The electrochemical p roperties of these new compounds are also reported.