Chelating diamide complexes of titanium: new catalyst precursors for the highly active and living polymerization of α-olefins
作者:John D. Scollard、David H. McConville、Jagadese J. Vittal、Nicholas C. Payne
DOI:10.1016/s1381-1169(97)00174-x
日期:1998.2
titanium dimethyl complexes are active catalysts for the polymerization of 1-hexene, when activated with methylaluminoxane (MAO). Activities up to 350,000 g of poly(1-hexene)/mmol catalyst·h were obtained in neat 1-hexene. These systems actively engage in chain transfer to aluminum. Equimolar amounts of 5a or 5b and B(C6F5)3 catalyze the living aspecific polymerization 1-hexene. Polydispersities (Mw/Mn)
RHN(CH 2)3 NHR(1a,b)(a,R = 2,6- i Pr 2 C 6 H 3 ; b,R = 2,6-Me 2 C 6 H 3)与2当量的反应的BuLi溶液,然后是2当量的ClSiMe 3,得到甲硅烷基化的二胺R(Me 3 Si)N(CH 2)3 N(SiMe 3)R(3a,b)。3a,b与TiCl 4的反应产生二氯化物络合物[RN(CH 2)3 NR] TiCl 2(4a,b)和两个当量的ClSiMe 3。X射线研究4a(P2 1 / n,a = 9.771(1)Å,b = 14.189(1)Å,c = 21.081(2)Å,β = 96.27(1)°,V = 2905.2(5 )埃3,ž = 4,Ť = 25°C,- [R = 0.0701,- [R瓦特= 0.1495)显示约钛扭曲的四面体几何与芳基躺在垂直于在TiN 2-飞机。化合物4a,b与2当量的MeMgBr反应,得到二甲基衍生物[RN(CH