Metallocene Catalysts for Olefin Polymerization

The Vinyl Homopolymerization of Norbornene

“…[28,29,30,39] The term "metallocene" often refers to catalysts derived from metallocene dichloride precatalysts.…”

Borane Activators for Late-Transition Metal Catalysts in Norbornene Polymerization

“…MAO combines the function of alkyl-transfer agent, activator and scavenger. [10,17] The molar metal/borane/TEA and metal/MAO ratios were 1 : 9 : 10 and 1 : 100, respectively. We would like to emphasize that the cocatalyst quantities required were much less with borane/TEA than with MAO for similar monomer conversions and activities.…”

Facile, aprotic degradation of η-CpZrCl3·dme by ternary sodium/group 14 tert-butoxides: From η-CpZrCl3·dme back to NaCp in two easy steps

“…This oil hardened to a white, waxy solid, which melted at 32 C. The compound has the expectedly simple 1 H NMR spectrum, consisting of singlets at 6.34 (5 H) and 1.24 (27 H), respectively. The peak pattern is identical to that of 4, whose synthesis from the comproportionation of Cp 2 Mg and Zr(O t Bu) 4 recently reported [21]. Unfortunately, the report gave only the NMR spectra and elemental analysis data, but neither the mode of isolation of 4, nor its state of matter was described.…”

“…Thus, the bent metallocenes of the Group 4 metals are synthesized from the tetrachlorides with two equivalents of NaCp. Group 4 metallocenes have found uses in a myriad of synthetic applications [1e3], ranging from single-step organic transformations to industrial-scale polymer catalysis [4,5]. Outside of the iron group few transition metals rival the Group 4 metals in the thermal and chemical robustness of their Cp derivatives.…”