Group 3 metal catalysts for ethylene and α-olefin polymerization

This review focuses on the use of group 3 organometallic catalysts for ethylene and alpha-olefins polymerization, as well as for functionalization of such poly(alpha-olefin) chains. It describes the evolution from initially designed neutral alkyl (hydrido) bis(cyclopentadienyl) complexes of trivalent lanthanides towards ansa-bridged ligand systems, constrained-geometry hemi-metallocenes, divalent lanthanidocenes, and the most recent cyclopentadienyl-free systems. (C) 2004 Elsevier B.V. All rights reserved.