Asymmetric Synthesis of Complex Molecules Using Polyfunctional Cyclopropanes

在这个由化学系化学合成计划资助的项目中，Andrew Harned教授正在开发基于独特小分子家族所表现出的不寻常反应性的新合成方法。除了探索这些小分子环丙烷的反应性之外，正在开发新的催化剂来合成这些材料作为单一立体异构体。一些生物活性的天然产物正在使用这种方法合成。除了这些实验室的努力，从这项工作中选择的数据正在被用来填充基于网络的NMR FID数据库，该数据库也正在PI的实验室中开发。这一独特的教育资源正在向世界各地的教师提供。该项目的化学重点是开发有效合成复杂分子的新方法。主要目标是利用高度官能化的三环环丙烷家族固有的不寻常的反应模式。将这些化合物与亲核试剂或亲电试剂反应，得到具有高区域和立体选择性的高度官能化的开环产物。环丙烷的必要起始原料，对映体富集的对-喹啉，用新的手性芳基碘催化剂合成。与这些方法学研究同时，独特的环丙烷被用作构建几种天然产物的关键中间体，特别是azaphilone内酯和briarane二萜类化合物。

In this project funded by the Chemical Synthesis program of the Chemistry Division, Professor Andrew Harned is developing new synthetic methodologies based on the unusual reactivity displayed by a family of unique small molecules. In addition to exploring the reactivity of these small-molecule cyclopropanes, new catalysts are being developed to synthesize these materials as single stereoisomers. Several biologically active natural products are being synthesized using this methodology. In addition to these laboratory efforts, selected data from this work are being used to populate a web-based NMR FID database that is also under development in the PI's laboratory. This unique educational resource is being made available to instructors around the world.The chemical focus of the project concerns the development of new methodology for the efficient synthesis of complex molecules. The main goal is to harness the unusual reactivity patterns inherent to a family of highly functionalized, tricyclic cyclopropanes. Reacting these compounds with either nucleophiles or electrophiles affords highly functionalized, ring-opened products with high regio- and stereoselectivity. The requisite starting materials for the cyclopropanes, enantioenriched para-quinols, are synthesized with new chiral aryl iodide catalysts. Concurrent with these methodology studies, the unique cyclopropanes are being used as key intermediates for the construction of several natural products, specifically azaphilone lactones and briarane diterpenoids.