Novel Inorganic Ligand Architectures for Catalysis

T.Keith Hollis，加州大学河滨分校，由无机化学、生物无机化学和有机金属化学项目支持，研究茂磷催化剂。这些化合物具有一个或两个与过渡金属配位的磷杂环戊二烯配体。芳环上的磷导致了独特的异构化途径，包括环滑移和P-反转。这些过程具有立体化学效应，并可导致茂金属、手性催化剂和振荡催化剂的动态拆分。手性茂金属催化剂已被应用于烯烃聚合、环氧化物开环、不对称氢化、不对称烯丙基烷基化和烯丙醇对映体选择性异构化等反应。该项目中开发的杂金属茂化合物为制药和精细化学品生产商感兴趣的许多转化提供了新的潜在催化剂。从事这个项目的学生将接受有机金属和有机化学的培训，包括平行组合化学和聚合物化学。

T. Keith Hollis, University of California-Riverside, is supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program for studies of phosphametallocene catalysts. These compounds have one or two phosphacyclopentadienyl ligands coordinated to a transition metal. The phosphorus in the aromatic ring gives rise to unique isomerization pathways, including ring slip and P-inversion. These processes have stereochemical consequences and can lead to the dynamic resolution of metallocenes, chiral catalysts and oscillating catalysts. Extensions to other heterometallocene systems such as boratabenzene, pyrrolyl and arsolyl may lead to similar isomerizations and yield additional useful chiral catalysts.Chiral metallocene catalysts have been applied in several processes, including olefin polymerization, epoxide ring opening, asymmetric hydrogenation, asymmetric allylic alkylation and enantioselective isomerization of allylic alcohols. The heterometallocenes developed in this project offer new potential catalysts for many transformations of interest to pharmaceutical and fine chemical producers. Students working on this project will be trained in organometallic and organic chemistry, including parallel combinatorial chemistry, and in polymer chemistry.