Methylene-Bridged Metallocenes with 2,2′-Methylenebis[1H-inden-1-yl] Ligands: Synthesis, Characterization, and Polymerization Catalysis of a Synthetically Simple Class ofC2- andC2v-Symmetricansa-Metallocenes
7-dimethyl-1H-inden-1-yl]}zirconium ([ZrCl2(5′)] is the most open. The mixture [ZrCl2(1′)]/methylalumoxane (MAO) is inactive in the polymerization of both ethylene and propylene, while the metallocenes with substituted indenyl ligands polymerize propylene to atactic polypropylene of a molecular mass that depends on the size of the alkyl or aryl groups at the 1,1′ positions of the ligand. Ethene is polymerized