Ferrocenyl Carbonium Ions and Related Cationic Complexes. Structure and Stabilisation Mechanism

The review presents data on the structure and mechanism of the stabilisation of ferrocenyl carbonium ions and related cationic complexes with different types of hydrocarbon ligands. The results obtained in the study of complex carbonium ions by X-ray diffraction, ⁵⁷Fe Mössbauer spectroscopy, and ¹H, ¹³C, ¹⁹F, ⁵⁷Fe, and ¹⁸⁷Os NMR are compared. It is shown that the ability of the metal atom to interact directly with the carbonium ion centre generated in the β-position relative to it is a general property of transition metal complexes.
The bibliography includes 132 references.