2-Lithioindenyllithium: An Easily Accessible Intermediate for the One-Pot Synthesis of Single- and Double-Functionalised 2-Indene Derivatives
11 April 2006 (eFirst)
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.
2-lithioindenyllithium - 2-indene derivatives - silicon-bridged ligand
WangB, and GruterGJM. inventors; (DSM) Patent Appl. WO 02079272. Chem. Abstr. 2002, 137, 777999
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Currently employed with Avantium Technologies Amsterdam.3
Yields determined by 1H NMR of the crude reaction mixture.7
Wang, B.; unpublished results.