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Updated: Jun 21, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
PCNCP ligands in the chromium-catalyzed oligomerization of ethylene: tri- versus tetramerization
Christian Klemps1, Elina Payet, Lionel Magna
1Laboratoire Hétéroéléments et Coordination, Ecole Polytechnique-CNRS, 91128 Palaiseau cedex, France.
Abstract:
Chromium(III) complexes bearing R'N(CH2PR2)2 (PCNCP) ligands have been prepared. Upon activation with methylaluminoxane, these complexes proved to be effective in the selective tri- and tetramerization of ethylene. The formation of either 1-hexene or 1-octene was found to be highly dependent on the steric bulk of the substituents R on the phosphine moieties. This observation was rationalized by using density functional theory calculations on selected steps of the metallacyclic mechanism of the ethylene oligomerization reaction.
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