Alkylidenverbrückte dissymmetrische zweikernige Metallocenkomplexe als Katalysatoren für die Ethylenpolymerisation
作者:Matthias Deppner、Ralf Burger、Helmut G. Alt
DOI:10.1016/j.jorganchem.2003.11.043
日期:2004.4
dissymmetric alkylidene bridgeddinuclearmetallocene complexes of titanium, zirconium and hafnium and some of the corresponding mononuclear reference complexes. The influence of structural parameters on the polymerization behaviour of the MAO activated complexes is systematically investigated for homogeneous ethylene polymerization. The dinuclear catalysts show higher polymerization activities than a mixture
Amido functionalized ansa half-sandwich dichloride complexes of titanium, zirconium and hafnium with alkyl and ω-alkenyl substituents as homogeneous and self-immobilizing catalyst precursors for ethylene polymerization
作者:Helmut G Alt、Alexander Reb、Wolfgang Milius、Annette Weis
DOI:10.1016/s0022-328x(01)00781-1
日期:2001.5
A total of 24 amido functionalized ansa half-sandwich dichloride complexes of titanium, zirconium and hafnium with cyclopentadienyl or indenyl ligands have been prepared, characterized and used for catalytic ethylene polymerization. Alkyl and ω-alkenyl substituents on the aromatic system influence the polymerization activity of the catalysts and the properties of the produced polyethylene. After activation
Ruthenium-Catalyzed Cyclization of 2-Alkyl-1-ethynylbenzenes via a 1,5-Hydrogen Shift of Ruthenium−Vinylidene Intermediates
作者:Arjan Odedra、Swarup Datta、Rai-Shung Liu
DOI:10.1021/jo062573l
日期:2007.4.1
Catalytic cyclization of 2-alkyl-1-ethynylbenzene derivatives was implemented by TpRuPPh3(CH3CN)2PF6 (10 mol %) in hot toluene (105 °C, 36−100 h) to form 1-substituted-1H-indene and 1-indanone products; such cyclizations proceeded more efficiently for substrates bearing electron-rich benzenes. We propose that the cyclization mechanism involves a 1,5-hydrogen shift of initial metal−vinylidene intermediate
通过在热甲苯(105°C,36-100 h)中的TpRuPPh 3(CH 3 CN)2 PF 6(10 mol%)进行2-烷基-1-乙炔基苯衍生物的催化环化反应以形成1-取代的-1 H -茚和1-茚满酮产品;对于带有富电子苯的底物,这种环化反应更有效。我们提出环化机理涉及初始金属-亚乙烯基中间体的1,5-氢转移。