Enantioselective Allylmetal-Aldehyde, -Acetal and Aldol Reactions

本项目包含三个子项目，其中第一个子项目将使用三个模型来探索烯氧基硅烷与醛反应的过渡结构偏好。研究双键取向、路易斯酸的作用和手性路易斯酸的表面偏好。第二个子项目将发展一般的合成方法，包括使用有机锡试剂作为亲核试剂进行手性缩醛的立体选择性打开。研究的第三个领域涉及基于菌株释放刘易斯酸的新型手性刘易斯酸的开发，催化不对称醛醇缩合的发明，金属环丁烷催化醛类不对称烯丙化反应的研究及五配位硅酸盐配合物催化醛类不对称烯丙化反应试剂的制备。有了这个更新奖，合成有机项目正在支持伊利诺伊大学厄巴纳分校化学系的斯科特·e·丹麦博士的研究。本研究的主要目的是：1)阐明硅化合物一类重要反应的立体化学控制因素；2)扩大有机锡试剂的合成用途；3)开发新的不对称合成催化反应。不对称合成导致在一组复杂的起始物质的反应中，只优先产生许多可能的产物中的一种，这对于高效合成大分子有机分子至关重要。

This project contains three subprojects, in the first of which three models will be used to probe the transition structure preferences in the reaction of enoxysilanes with aldehydes. Double bond orientation, the role of Lewis acids and facial preferences with chiral Lewis acids will be studied. The second subproject will develop general synthetic methodology involving the use of organotin reagents as nucleophiles for stereoselective opening of chiral acetals. The third area of study involves development of a new class of chiral Lewis acids based on strain-release Lewis acidity, the invention of a catalytic asymmetric aldol condensation, the study of a catalytic asymmetric allylation of aldehydes using metallacyclobutanes and preparation of a reagent for asymmetric allylation of aldehydes using pentacoordinate siliconate complexes. %%% With this renewal award, the Synthetic Organic Program is supporting the research of Dr. Scott E. Denmark of the Department of Chemistry at the University of Illinois, Urbana. The primary objectives of the research are: 1) to elucidate those factors responsible for stereochemical control in an important family of reactions of silicon compounds 2) to expand the synthetic utility of organotin reagents, and 3) to develop new catalytic reactions for asymmetric synthesis. Asymmetric synthesis leads to the preferential production of only one of the many products possible from reactions of a complicated set of starting materials, and is of critical importance for the efficient synthesis of large organic molecules.