Abstract
We found that double-silicon-bridged bisindenyl complexes of early transition metals of group 4 are able to produce polyethylenes with high molecular weights and narrow molecular-weight distributions having high α-olefin incorporation. The bottle-neck for the synthesis of these complexes is the ligand synthesis. The corresponding ligands could be obtained via a three-step procedure with low (15%) overall yields. We found that the use of the new 2-lithioindenyllithium enhanced the overall yield to 50% in a one-pot procedure.
Key words
2-lithioindenyllithium - 2-indene derivatives - silicon-bridged ligand
References
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