[2-(Dimethylamino)ethyl]-substituted cyclopentadienyltitanium complexes (3-6) have been synthesized and characterized. Structural data indicates intramolecular coordination of the dimethylamino group to titanium. The catalytic activities and selectivities for styrene, ethylene, and propylene polymerization with 3-6 have been compared with the reference compounds CpTiCl(3) (1), Cp*TiCl3 (2), and Cp(2)TiCl(2) (7), and are consistent with Ti-N Lewis acid-base interaction.