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RESEARCH PRODUCT

Non-bridged amido cyclopentadienyl complexes of titanium: synthesis, characterization, and olefin polymerization catalysis

Piet-jan SinnemaThomas P. SpaniolJun Okuda

subject

EthyleneLigandOrganic ChemistryAlkylationPhotochemistryBiochemistryMedicinal chemistryStyreneCatalysisInorganic Chemistrychemistry.chemical_compoundchemistryPolymerizationCyclopentadienyl complexMaterials ChemistryMoleculePhysical and Theoretical Chemistry

description

Alkylation of Ti(η 5 -C 5 Me 5 )(NMe 2 )Cl 2 gives thermally stable, crystalline dialkyl complexes Ti(η 5 -C 5 Me 5 )(NMe 2 )R 2 (R=Me, CH 2 Ph, Ph). The molecular structure of the dibenzyl complex reveals an unprecedented conformation of the doubly bonded NMe 2 group which is turned parallel to the η 5 -C 5 Me 5 ligand, according to single-crystal X-ray diffraction studies. Treatment of the dibenzyl complex with B(C 6 F 5 ) 3 in d 5 -bromobenzene solution results in the quantitative formation of a thermally (>10°C) unstable monobenzyl cation as solvent-separated ion pair [Ti(η 5 -C 5 Me 5 )(NMe 2 )CH 2 Ph] + [PhCH 2 B(C 6 F 5 ) 3 ] − which efficiently polymerizes styrene syndiospecifically at 25°C. Ethylene is polymerized by Ti(η 5 -C 5 Me 5 )(NMe 2 )Cl 2 methylalumoxane with low activity.

https://doi.org/10.1016/s0022-328x(99)00701-9