New Reactions for Organic Synthesis

该计划的总体目标是开发新的化学反应和合成策略，使复杂的有机化学品能够有效地合成。由于碳在有机化学中的核心重要性，我们的研究集中在开发新的选择性(化学、区域和立体选择性)方法来形成碳-碳键。建议的研究范围很广，既包括旨在对化学反应活性有一个基本了解的机理研究，也包括旨在探索我们正在开发的反应用于制备特定复杂目标结构的效用的全合成研究。在拟议的项目期间，我们的大部分工作将集中于开发新的环化反应，以制备中环杂环和碳环。在所有类型的环系(小的、普通的、中等的和大的)中，现有的方法对于制备中环最不令人满意。我们的研究是基于当前授权期内的一项重要发现，即通过简单的缩醛-烯烃环合反应可以有效地生成中环醚。其他研究将集中在开发新的方法，以制备对映体纯的单环β-内酰胺类药物。我们还将继续我们的合作计算和实验研究，以开发新的模型来预测高度官能化的环加成组分的Diels-Adler反应的区域和立体选择性。

The general objective of this program is to develop new chemical reactions and synthesis strategies that will allow complex organic chemicals to be synthesized efficiently. As a result of the central importance of carbon in organic chemistry,our studies focus on the development of new selective (chemo-,regio-, and stereoselective) methods for forming carbon-carbon bonds. The studies proposed are broad in scope and encompass both mechanistic studies aimed at developing a fundamental understanding of chemical reactivity and total synthesis studies aimed at exploring the utility of the reactions we are developing for the preparation of specific complex target structures. The majority of our efforts during the proposed project period will focus on developing new cyclization reactions to prepare medium ring heterocycles and carbocycles. Of all the types of ring systems (small, common, medium and large) existing methods are least satisfactory for preparing medium rings. Our studies are based on an important discovery made during the current grant period that medium ring ethers can be formed efficiently by simple acetal-alkene cyclizations. Other investigations will focus on developing new methods to prepare monocyclic b-lactams in enantiomerically pure form. We will also continue our collaborative computational and experimental investigations to develop new models for predicting regio- and stereoselectivity in Diels-Adler reactions of highly functionalized cycloaddition components.