Titanium and zirconium complexes containing the new 2,3-dimethyl-1,4-diphenylcyclopentadienyl ligand. Synthesis, characterization and polymerization behavior

Abstract

An easy and inexpensive three-step synthesis of new 2,3-dimethyl-1,4-diphenylcyclo-pentadiene (3) ligand and the titanium (4) and zirconium (5) homometallocene dichlorides and the mixed ligand zirconium complex [ZrCl2(η5-C5H-2,3-Me2-1,4-Ph2)(η5-C5H5)] (6) prepared thereof are described. The polymerisation of ethene using 4 - 6/MAO catalysts revealed that zirconocene complexes 5 and 6 displayed moderate and high activity, respectively, whereas the titanium catalyst 4/MAO was inactive. The crystal structures of 4 and 5 have been determined by X-ray crystallography.

Keywords

• titanocene
• zirconocene
• polymerization
• 2,3-dimethyl-1,4-diphenylcyclopentadiene
• ethene
• crystal structure
• sterically demanding pentaphenylcyclopentadienyl
• elastomeric polypropylene
• olefin polymerization
• polyphosphoric acid
• Ziegler-catalysts