206121-15-5Relevant academic research and scientific papers
Triazamethylenemethane complexes of zirconium and tantalum
Rodriguez, George,Sperry, Caroline K.,Bazan, Guillermo C.
, p. 5 - 28 (1998)
Addition of [Li2(THF)4][C(NPh)3] (2) to a THF solution of Cp *ZrCl3 (Cp * = C5Me5) yields, after recrystallization in Et2O, the zwitterionic species Cp* [C(NPh)3]ZrCl2Li(Et2O)(THF) (3). Treating 3 with excess methylaluminoxane (MAO) affords a homogeneous Ziegler-Natta catalyst for ethylene polymerization. Addition of LiNPh2 to 3 allows for Cl substitution to give the new product Cp*[C(NPh)3]Zr(NPh2)C1Li(THF)2 (4). A single crystal diffraction study of 4 reveals that the [C(NPh)3] ligand is η2-bound. The group 5 complex Cp*[C(NPh)3]TaMe2 (5) was prepared by addition of 2 to Cp * TaMe2Cl(OSO3CF3). The X-ray diffraction structure of 5 shows that the [C(NPh)3] ligand is η2-bound to tantalum and that, when compared to 4, there is less electron delocalization across the inner core of [C(NPh)3].
