Stoichiometric and Catalytic Transformations Using Transition Metal Aryloxides

该奖项在无机，生物无机和有机化学 该计划与办公室的仪器的贡献， 多学科活动支持过渡金属研究 普渡大学化学系Ian P. Rothwell博士 大学 芳氧基钛是用于区域-和 不饱和有机分子的立体选择性偶联。 环二烯 并且各种烯烃和炔烃已经显示出经历这种类型的 反应 在这里，反应的合成有用性将是 利用和控制产品几何形状的机制将是 测定 此外，低价钨芳氧化物将进行测试 作为4电子还原剂。 一种新开发的配体， 2，6-二苯酚-3，5-二叔丁基苯酚，将用于合成高 价前过渡金属有机金属化合物和高价 亲电的低配位过渡金属化合物。 相比之下 与过去使用的类似配体相比，该配体不经历 金属化 通过这些内的邻苯基取代基螯合 配体为研究新型金属芳烃打开了大门 键合和反应性，包括CH-键活化和立体特异性 偶合器. 与过渡金属键合的空间大体积基团通常有效地与过渡金属键合。 防止一定尺寸和形状的反应物接触金属 中心 因此，发生的反应产生产物 具有优选的几何形状。 在这项研究中，庞大的醇盐基团将被 用于实现对某些钛的立体特异性反应， 钨促进的有机合成反应 化合物.

This award in the Inorganic, Bioinorganic, and Organometallic Chemistry Program with a contribution for instrumentation from the Office of Multidisciplinary Activities supports research on transition metal aryloxides by Dr. Ian P. Rothwell, Department of Chemistry, Purdue University. Titanium aryloxides are catalysts for regio- and stereoselective coupling of unsaturated organic molecules. Cyclodienes and various olefins and alkynes have been shown to undergo this type of reaction. Here the synthetic usefulness of the reaction will be exploited and the mechanism that controls product geometry will be determined. In addition, low valent tungsten aryloxides will be tested as 4-electron reducing agents. A newly developed ligand, 2,6-diphenol-3,5-di-tert-butylphenol, will be used to synthesize high valent early transition metal organometallic compounds and highly electrophilic, low coordination transition metal compounds. In contrast to analogous ligands used in the past, this ligand does not undergo metalation. Chelation via ortho-phenyl substitutents within these ligands opens the door for investigation of new types of metal-arene bonding and reactivity, including CH-bond activation and stereospecific coupling. Sterically bulky groups bound to transition metals are often effective in preventing reactants of certain size and shape from accessing the metal center. As a consequence, the reactions that do occur produce products with a preferred geometry. In this study, bulky alkoxide groups will be used to effect stereospecific reactivity to some titanium- and tungsten-promoted reactions of utility in the synthesis of organic compounds.