Direct Observation of Insertion Events atrac-(C2H4(1-indenyl)2)Zr(MeB(C6F5)3)−Polymeryl Intermediates: Distinction between Continuous and Intermittent Propagation Modes
- 24 January 2003
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 125 (7) , 1710-1711
- https://doi.org/10.1021/ja028070o
Abstract
The propagating species for 1-hexene, propene, and ethene polymerization as catalyzed by [rac-(C2H4(1-indenyl)2)Zr(CH3)][CH3B(C6F5)3] has been intercepted at T < −40 °C and characterized by NMR methods. Observation of the propagating species permits direct monitoring of initiation, propagation, and termination processes by NMR. Detailed examination of alkene incorporation into Zr−polymeryl species using 13C-labeled 1-alkenes supports a continuous insertion mechanism whereby the anion re-coordinates after each alkene insertion.Keywords
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