NEW ASYMMETRIC PROCESSES FOR USE IN ORGANIC SYNTHESIS

这项研究旨在发现和开发新的不对称过程 用于合成对映体纯的有机物质。发送到 在实现这一目标的程度上，许多精细化学品的合成 产品，特别是药品，将被简化。 大约一年前，在这笔赠款的支持下，我们发现了一位将军 烯烃不对称双羟基化的催化方法。在… 这项提议的核心是开发这种新的不对称的计划 进程。将作出重大努力，以寻找更好的 同时试图实现不对称配体的机械化 洞察力，这将使配体设计工作更加理性。ADH 该工艺也正在扩展到催化羟胺化法领域。 将仔细检查该工艺的底物范围。目前 几乎所有的烯烃都是一个可能的候选者，因为不对称诱导 不依赖于底物与催化剂的先前结合。 现在容易获得的高手性二醇的合成应用将 得到重视。主要的推力依赖于将二醇转化为 类似环氧化物的合成子，如1，2-环硫酸盐。这部作品有一个 “合成方法”方向，但也包括有计划的合成 各种生物活性物质(例如，β-内酰胺，地尔硫卓， 油菜素内酯、抗生素AT-125、赤霉醇等)。 C2对称性的同手性二醇现在很容易制备，并将被 作为其他不对称过程的手性辅助剂/配体被研究。 被分离的成功的不对称双羟基化所鼓舞 烯烃，这个项目持续的长期目标是不对称的 分离的烯烃的环氧化反应。

This research seeks to discover and develop new asymmetric processes for use in the synthesis of enantiomerically pure organic substances. To the extent that this aim is realized, the syntheses of many fine chemical products, especially pharmaceuticals, will be simplified. About a year ago, under support by this grant, we discovered a general catalytic method for the asymmetric dihydroxylation (ADH) of olefins. At the heart of this proposal are the plans for developing this new asymmetric process. A major effort will be directed toward finding even better asymmetric ligands while at the same time trying to achieve the mechanistic insight which will make the ligand-design work more rational. The ADH process is also being extended to the area of catalytic oxyamination. The substrate scope of the process will be carefully examined. At present almost any olefin is a possible candidate since the asymmetric induction does not depend on prior binding of the substrate to the catalyst. Synthetic applications for the now readily available homochiral diols will receive emphasis. The main thrust relies on conversion of the diols into epoxide-like synthons, such as 1,2-cyclic sulfates. This work has a "synthetic methods" orientation but also includes planned syntheses of various biologically active substances (e.g. beta-lactams, diltiazem, brassinolide, antibiotic AT-125, cianidanol, etc.). Homochiral diols of C2 symmetry are now easily prepared and will be examined as chiral auxillaries/ligands for other asymmetric processes. Encouraged by the successful asymmetric dihydroxylation of isolated olefins, a continuing long-range goal of this project is asymmetric epoxidation of isolated olefins.