Titanium and Zirconium Amido Complexes Ligated by 2,2‘-Di(3-methylindolyl)methanes: Synthesis, Characterization, and Ethylene Polymerization Activity

2,2‘-Di(3-methylindolyl)methanes (L2H2) are introduced as dianionic,
bidentate ligands of reduced π-donating ability. Four complexes
of the type L2Ti(NEt2)2 and L2Zr(NEt2)2(THF) have been synthesized
and characterized by elemental analysis, NMR (1H, 13C) spectroscopy, and X-ray crystallography. Structural data confirm the reduced
π-donating ability of the η1-indolyl moiety compared to that of
diethylamido. Preliminary catalytic activities of these group 4
complexes for the polymerization of ethylene are reported.