Phosphanylalkylcyclopentadienyl ligands: synthesis, molecular structures and catalytic properties of [{(η5-C5H4)CMe2PHR}CrCl2(PMe2Ph)] (R=Ph, )
摘要:
Li[(C5H4)CMe2PHPh] reacted with [CrCl3(THF)(3)] with formation of a mixture of products, among which only [{(eta(5)-C5H4)CMe2PPh}CrCl](2) (1) could be isolated. However, when [CrCl3(PMe2Ph)(3)] was treated with Li[(C5H4)CMe2PHR], the complexes [{(eta(5)-C5H4)CMe2PHR}CrCl2(PMe2Ph)] (R = Ph (2), Bu-t (3)) were obtained in moderate yield. Complexes 1 and 2 were characterised by X-ray crystallography, 1-3 by IR spectroscopy. In the solid state, a phosphanido-bridged dimer is observed for 1, while 2 and 3 are monomeric complexes without coordination of the phosphanyl group of the cyclopentadienyl ring. 2 and 3 were also characterised by mass spectrometry and NMR and UV-Vis spectroscopy, and their magnetic moments were determined. 2 and 3 were studied in the catalytic polymerisation of ethylene with methylalumoxane (MAO) as cocatalyst. (C) 2004 Elsevier Ltd. All rights reserved.