Synthesis,Characterization, and Syndio‐Specific Styrene Polymerization of Pyrrolyl‐Substituted Cyclopentadienyl Scandium Complexes

Acid‐base reaction of Sc(CH₂C₆H₄NMe₂‐o)₃ with 1 equiv. of pyrrolyl‐substituted cyclopentadienyl ligand C₄H₂Me₂NSiMe₂C₅Me₄H in toluene gave the half‐sandwich scandium bis(aminobenzyl) complex (C₄H₂Me₂NSiMe₂C₅Me₄)Sc(CH₂C₆H₄NMe₂‐o)₂ ( 2 ). Amine elimination between ScN(SiHMe₂)₂]₃(THF) and one equivalent of C₄H₂Me₂NSiMe₂C₅Me₄H afforded the scandium bis(silylamide) complex (C₄Me₂H₂NSiMe₂C₅Me₄)Sc(NSiHMe₂)₂SiMe₂](THF) ( 3 ). Both scandium complexes 2 and 3 were characterized by elemental analysis, NMR spectroscopy, and single‐crystal X‐ray diffraction. 2 and 3 could serve as highly active precursors for styrene polymerization to give syndio‐tactic polystyrene (rrrrrr > 99 %).