917571-63-2Relevant academic research and scientific papers
Highly active chromium-based selective ethylene tri-/tetramerization catalysts supported by PNPO phosphazane ligands
Zhou, Yusheng,Wu, Hongfei,Xu, Sheng,Zhang, Xuejun,Shi, Min,Zhang, Jun
, p. 9545 - 9550 (2015)
Novel Cr(iii) catalysts supported by PNPO phosphazane ligands of the type Ph2PN(R)P(Ph)OAr have been prepared, all of which, upon activation with MMAO-3A, are highly active in ethylene tri-/tetramerization with considerable selectivity. The effect of ligand substitution on the catalytic performance has been examined. The Cr precatalyst supported by the PNPO phosphazane ligand with an N-cyclohexyl achieved high activity of 316.7 kg (g Cr h-1)-1 and a high total selectivity of 85.1% towards valuable 1-hexene (45.7%) and 1-octene (39.4%) using chlorobenzene as the solvent at 35 bar and 40 °C. In methylcyclohexane, the precatalyst supported by [Ph2PN(iPr)P(Ph)OPh] exhibited a higher 1-octene selectivity (54.0%) with a considerable activity of 73.3 kg (g Cr h-1)-1 at 35 bar and 40°C. With the fine-tuned ligand backbone, such a PNPO phosphazane-based catalyst system provides a mode for precise understanding of the impact of ligand variations on catalytic performance.
Ligand compound and preparation method and application thereof
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Paragraph 0032; 0033; 0034; 0035; 0036; 0037; 0038, (2017/04/13)
The invention relates to a ligand compound as shown in a general formula I. According to the general formula I, R is hydrogen or an alkyl group or a naphthenic group or an aryl group, and R' is hydrogen or an alkyl group or an alkoxy group or a hydroxyl group or a halogen. The invention further relates to a preparation method and application of the ligand compound. Please see the general formula I in the description.
