New Alkene Difunctionalization Reactions for Organic Synthesis

描述(申请人提供)：饱和杂环的立体选择性结构在有机合成中仍然是一个重要的挑战，因为许多具有生物活性的天然分子都含有这些亚基。虽然杂环构筑方法的发展长期以来一直是人们感兴趣的，但一些重要的目标很难使用现有的转化以立体选择性的方式产生。此外，许多方法并不容易从单一的前体制备许多类似物。我们研究计划的长期目标是开发新的反应，用于构建具有生物活性的富含对映体的杂环。这项研究的目标是开发新的烯烃碳杂功能化反应，用于合成几类特定的生物相关杂环，并开发用于不对称碳杂官能化反应的新催化剂，这是我们长期目标的重要步骤。这些目标将通过以下三个具体目标来实现：(1)开发新的烯烃碳杂化反应以构建复杂的双环杂环；(2)开发新的不对称烯烃碳杂化反应；(3)开发新的烯烃碳杂化反应用于含缩醛或氨基立体中心的分子的对映选择性合成。所有这三个目标都涉及到新型钯催化的芳基/烯基卤化物与含侧链烯的胺/醇的反应。这些反应将在一步中形成两个键和两个立体中心，以高效和立体选择性的方式生成所需的杂环，并将应用于合成具有生物意义的目标。拟议的研究具有创新性，因为它们将导致新的战略层面的脱节，可以由工业界和学术界的各种化学家应用于复杂分子的合成。此外，这些研究将延伸烯烃碳杂官能化过程的前沿，并将为控制这类重要转化中的不对称诱导因素提供洞察。所得知识可用于其他新反应的进一步开发。这项拟议的研究意义重大，因为在这些研究期间开发的新转化将为获得重要的生物活性化合物提供便利的途径，而现有方法很难产生这些化合物。这将扩大可用于药物化学/药物开发的杂环构建块的范围。此外，这些新的转化还将允许容易地产生感兴趣的分子的类似物，可用于优化先导化合物的生物或药学性质。

DESCRIPTION (provided by applicant): The stereoselective construction of saturated heterocycles remains an important challenge in organic synthesis, as many biologically active natural molecules contain these subunits. Although the development of methods for the construction of heterocycles has been of longstanding interest, a number of important targets are difficult to generate in a stereoselective manner using existing transformations. In addition, many methods are not readily amenable to the preparation of numerous analogs from a single precursor. The long-term goal of our research program is to develop new reactions for the construction of enantiomerically enriched, biologically active heterocycles. The objectives of the research outlined in this proposal, which represent significant steps toward our long term goal, are to develop new alkene carboheterofunctionalization reactions for the synthesis of several specific classes of biologically relevant heterocycles, and to develop new catalysts for asymmetric carboheterofunctionalization reactions. These objectives will be achieved by pursuing three specific aims: (1) to develop new alkene carboheterofunctionalization reactions for the construction of complex bicyclic heterocycles; (2) to develop new asymmetric alkene carboheterofunctionalization reactions; and (3) to develop new alkene carboheterofunctionalization reactions for the enantioselective synthesis of molecules bearing acetal or aminal stereocenters. All three aims involve the invention of new types of Pd-catalyzed reactions of aryl/alkenyl halides with amines/alcohols bearing pendant alkenes. These reactions will form two bonds and two stereocenters in one step to generate the desired heterocycles in an efficient and stereoselective manner, and will be applied to the synthesis of biologically significant targets. The proposed studies are innovative because they will lead new strategy-level disconnections that can be applied to complex molecule synthesis by a variety of chemists in both industry and academia. In addition, these studies will extend the forefront of alkene carboheterofunctionalization processes, and will provide insight into factors that can be used to control asymmetric induction in this important class of transformations. The knowledge gained can be used for the future development of other new reactions. The proposed research is significant because the new transformations developed during these studies will provide facile access to important biologically active compounds that are difficult to generate with existing methods. This will broaden the range of heterocyclic building blocks available for use in medicinal chemistry/drug development. In addition, these new transformations will also allow for facile generation of analogs of interesting molecules, which can be used to optimize biological or pharmaceutical properties of lead compounds.