The role of the ionic polynuclear complexes of the f-elements as components of diene cis-polymerization catalytic systems

This paper studies the catalytic behavior of several polynuclear complexes of the f-elements where there is no direct linkage between the f-element and the halogen. Results are obtained as an example of the cis-regulating capability of lanthanide catalytic systems where the active centers lack a halide function at the metal. Significantly, no fluorides of aluminum and lanthanide are formed in consequence of the detachment of fluoride anions from the C6F5 nuclei in the given case, even though similar processes are well known