Asymmetric Synthesis Based on Chiral Heterobicyclo{2.2.1}heptanes

在有机合成项目的支持下，张旭木教授， 宾夕法尼亚州立大学化学系的教授， 探索了手性杂双环（2.2.1）庚烷作为催化剂的用途， 用于对映选择性有机转化的助剂。 膦催化的（3+2）环加成反应提供了手性化合物， 环戊烯具有高度的区域和对映选择性， 由手性磷杂双环（2.2.1）庚烷介导。 相关不对称 探索了催化剂在亲核伽马中的适用性， 与带有吸电子基团的炔的加成反应， Baylis-Hillman反应和硫醚介导的环氧化反应， 醛的氮丙啶化。 手性氮杂双环（2.2.1）庚烷是 烯胺用作不对称去质子化的手性助剂， 烷基化和环加成反应。 开发合成方法变得越来越重要， 允许精确控制有机物的三维形态 分子，因为即使是结构上看似微小的差异 由两个相互关联的分子作为镜像显示， 很少导致化学性质的显著差异。 宾夕法尼亚大学化学系的Xumu Zhang教授 州立大学在有机合成项目的支持下， 探索实现这种高度受控的有机合成的方法 分子。 通过探索和发展由以下因素介导的反应 专门设计和定制的含磷或含氮 分子，张教授能够赋予特定的三维 形成这些反应的产物。 除了开发 张教授通过实际的合成方法， 这些分子转化的发生和重要目标 药物和医药中间体，以证明其合成 效用

With the support of the Organic Synthesis Program, Professor Xumu Zhang, of the Department of Chemistry at the Pennsylvania State University, explores the use of chiral heterobicyclo(2.2.1) heptanes as catalysts and auxiliaries for enantioselective organic transformations. Phosphine-catalyzed (3+2) cycloaddition reactions afford chiral cyclopentenes with a high degree of regio- and enantioselectivity when mediated by chiral phosphabicyclo(2.2.1)heptanes. Related asymmetric catalysts are explored for their applicability in nucleophilic gamma addition reactions with alkynes bearing electron withdrawing groups, the Baylis-Hillman reaction, and thioether-mediated epoxidation and aziridination of aldehydes. Chiral azabicyclo(2.2.1)heptanes are employed as chiral auxiliaries for asymmetric deprotonation, enamine alkylation, and cycloaddition reactions. It has become increasingly important to develop synthetic methods which allow precise control over the three-dimensional form of organic molecules, since even the seemingly minor difference in structure displayed by two molecules related to one another as mirror images not infrequently leads to a dramatic difference in chemical properties. Professor Xumu Zhang, of the Department of Chemistry at the Pennsylvania State University, with the support of the Organic Synthesis Program, explores methods to effect such highly controlled syntheses of organic molecules. By exploring and developing reactions which are mediated by specifically designed and tailored phosphorus- or nitrogen-containing molecules, Professor Zhang is able to impart specific three-dimensional forms to the products of these reactions. In addition to developing practical synthetic methods, Professor Zhang explores the mechanisms by which these molecular transformations take place and targets important drugs and pharmaceutical intermediates to demonstrate their synthetic utility.