PROTONATION OF METALLOCENES BY STRONG ACIDS. STRUCTURE OF THE CATION

Abstract

Ferrocene recently has been shown to form a stable complex salt of composition (C_(10_H_(10)Fe•HAlCl_4) in the presence of aluminum chloride and hydrogen chloride. This finding, together with the suggestion that the transition state for electrophilic substitution of ferrocene, ruthenocene and osmocene may involve initial interaction of the electrophile with the metal atom, prompted us to examine then.m.r. spectra of these moetallcenes in media of high acidity.