systems does not generally result in catalysts exhibiting lower activities and producing lower molecular weight polymers. An EPR study of the Cp*TiMe3/[Ph3C][B(C6F5)4] system in chlorobenzene at room temperature indicates that <0.01% of the titanium is present occasionally during polymerization as a complex of titanium(III), suggesting that a contribution to the catalytic processes by titanium(III) species
化合物的Cp *时间2 E(*的Cp =η 5 -C 5我5 ; E =我,C 6 ˚F 5,OC 6 ˚F 5,Cl)的具有三苯甲基四反应(
全氟苯基)
硼酸盐,[PH 3 C] [ B(C 6 F 5)4 ]形成热不稳定的二
钛配合物[(Cp * TiMeE)2(μ-Me)] [B(C 6 F 5)4 ],所有这些都作为高价
金属的来源亲电物质[Cp * TiMeE] +。这些[B(C 6 F 5)的活性的调查4 ] -作为
乙烯和
丙烯聚合催化剂的盐表明,它们比类似化合物Cp * TiMeE(μ-Me)B(C 6 F 5)3更具活性,这是因为[B(C 6 F 5)4 ] -是比[BMe(C 6 F 5)3 ] -更差的
配体。然而,与目前所认为的智慧相反,[Cp * TiMe 2 ] +的甲基
配体被更多的吸电子C 6 F 5,OC 6 F 5取代这些单
环戊二烯基体系中的C 1和C 1
配体通常不会导