Dynamic Behavior of Chiral Sulfonimidoyl-Substituted Allyl and Alkyl (Dimethylamino)titanium(IV) Complexes: Metallotropic Shift, Reversible β-Hydride Elimination/Reinsertion, and ab Initio Calculations of Allyl and Alkyl Aminosulfoxonium Ylides
作者:Hans-Joachim Gais、Peter R. Bruns、Gerhard Raabe、Rüdiger Hainz、Marcel Schleusner、Jan Runsink、Gadamsetti S. Babu
DOI:10.1021/ja0433828
日期:2005.5.1
orbital at the Calpha atom is periplanar to the S=Obond and that at the N atom periplanar to the Calpha-Ph bond. Variable-temperature NMR spectroscopy of the sulfonimidoyl-substituted alkyltitanium(IV) complex 16, which carries diethylamino groups at the Ti atom, revealed a dynamic behavior leading to a complete topomerization of all four methylene hydrogens of the Calpha-ethyl groups. Two fast processes
磺酰亚胺酰基取代的烯丙基钛 (IV) 配合物 E-1a-c 和 Z-1a-c 的变温 (1)H 和 (13)C NMR 光谱在 Ti 原子上带有二乙氨基,显示出快速的Ti 原子的 3-C,N 位移,导致差向异构 Cα-钛烯丙基配合物 A 和 C 与 N-钛烯丙基氨基锍叶立德 B 之间达到平衡。基于这些发现,建立了 E-1a 反应模型-c 和 Z-1a-c 与醛,其特点是 N-钛叶立德 B 在 α 位和 Cα-钛络合物 A 在 γ 位的区域和非对映选择性反应。亚甲基和烯丙基(二甲氨基)锍叶立德 10 和 14 的从头算模型分别揭示了短 Calpha-S 键,静电相互作用和负超共轭的稳定性,和低 Calpha-S 旋转障碍。叶立德优先采用 Calpha-S 和 Calpha-N 构象,其中 Calpha 原子上的孤对轨道与 S=O 键共面,而 N 原子与 Calpha-Ph 键共面。磺酰亚胺酰基取代的烷基钛
Homogeneous catalysts and olefin polymerization process
申请人:The Dow Chemical Company
公开号:US05194532A1
公开(公告)日:1993-03-16
Olefins are polymerized in the presence of a homogeneous catalyst represented by the formula LTi(NR.sub.2).sub.3 wherein L is a .pi.-bonded ligand selected from the group consisting of indenyl, C.sub.1 -C.sub.4 alkyl substituted indenyl, --OSiR.sub.3 substituted indenyl, R is a C.sub.1 -C.sub.4 alkyl group wherein each R attached to the same nitrogen atom is the same, but the R groups attached to different nitrogen atoms can be the same or different from those attached to the other nitrogen atoms.