DEVELOPING AN UNDERSTANDING OF ASYMMETRIC INDUCTION

这项建议旨在了解 催化不对称过程与手性化合物的设计与开发 用于不对称催化的过渡金属基催化剂。 手性合成技术的影响是多种多样的 对药物化学和制药领域至关重要 化学反应。这项建议的具体目的是：(一)了解 手性双磺酰胺的结构、性质及反应活性 配合物及其在不对称催化中的作用，(II)合成 (双磺酰胺)TiX2络合物(X=F，C1，Br)及其碱加合物， (三)探索化合物的合成、结构和反应性 用途广泛的双磺酰胺基钛双酰胺络合物 制备(双磺酰胺)钛物种的中间体， 和(Vi)开发六齿钛双磺酰胺化合物和 将它们应用于不对称催化。我们的长期目标是 发展对手性转移机制的理解。 建立了非对称流程，以便为 合理设计新的不对称反应。不对称的过程 合成是由对光学的需求的增加所推动的 纯净的材料。因此，这一领域的大部分焦点都转向了 涉及改进不对称过程中催化剂筛选的方法。 然而，很少有人了解催化体系，而且往往知之甚少。 了解催化剂的结构或运行情况。 我们用来实现目标的方法涉及到独立的 不对称反应催化剂的合成及其催化性能 表征(包括结构上的)。这些复合体就是 在不对称过程中进行测试，以评估其可行性 催化剂。

This proposal is directed toward the understanding of the mechanisms of catalytic asymmetric processes and the design and development of chiral transition metal based catalysts to be used in asymmetric catalysis. The impacts of chiral synthetic technology are quite diverse and are critical to the fields of medicinal chemistry and pharmaceutical chemistry. The specific aims of this proposal are: (I) To understand the structure, properties and reactivity of chiral bissulfonamido complexes and their role in asymmetric catalysis, (II) To synthesize (bissulfonamido)TiX2 complexes (X=F, C1, Br) and their base adducts, (III) To explore the synthesis, structure and reactivity of bissulfonamido titanium bisamide complexes which are versatile intermediates for the preparation of (bissulfonamido)titanium species, and (VI) to develop hexadentate titanium bissulfonamide compounds and apply them to asymmetric catalysis. Our long-term objective is to develop an understanding of the mechanism of chirality transfer in established asymmetric processes in order to build a foundation for the rational design of new asymmetric reactions. The course of asymmetric synthesis has been driven by an increase in the demand for optically pure materials. As result, much of the focus of this field has turned to improving methods to screen catalysts in asymmetric processes. However, rarely is the catalytic system understood and often little is known of the structure or the operation of the catalyst. The methods that we use to accomplish our goals involve the independent synthesis of proposed catalysts in asymmetric reactions and their characterization (including structurally). These complexes are then tested in the asymmetric process to evaluate their viability as catalysts.