CATALYTIC METHODS FOR STEREOSELECTIVE SYNTHESIS

立体选择性合成的催化方法

• 批准号: 1057818
• 负责人: Thaliyil RajanBabu
• 金额: $ 45万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1057818&HistoricalAwards=false
• 关键词: CATALYTIC; METHODS; STEREOSELECTIVE; SYNTHESIS

With this award, the Chemical Synthesis (SYN) Program is funding Professor T.V. RajanBabu of the Department of Chemistry at Ohio State University to explore catalytic methods in synthesis. The SYN Program finds particularly notable both the efficient Ni-mediated hydrovinylation transformation, and the impressive regiodivergent Y-salen-mediated aziridine opening chemistry developed in the last cycle. Key features of the research plan in the next cycle include investigation of the mechanism of the efficient stereoselective hydrovinylation reaction and development of an unprecedented asymmetric silyl(boryl)stannylation-diyne cyclization that would give axial chiral cyclic dienes. In most ring-forming reactions, even among highly catalytic and selective ones, the number of functional groups is often depleted in going from an unsaturated starting material to a product. In the aforementioned metal-catalyzed cyclization of diynes, enynes, allenynes and allene-aldehydes mediated by various X-Y reagents (X, Y = [R3Si], [R3Sn], [R2B]), there is a net increase in the number of functional groups in the product of the reaction. Moreover, in the case of the alpha,omega-diyne cyclization, the product (ZZ)-1,2-bis-alkylidene is axially chiral, and transfer of such chirality to centers of chirality around the newly formed ring is projected to add a new dimension to stereocontrol in cyclization reactions. These catalytic processes are part of an underlying green chemistry theme of this and related work in the RajanBabu research group. This theme carries over into the undergraduate organic teaching laboratory in which a project involving an aqueous, asymmetric biocatalytic reduction of unsymmetrical ketones has been introduced. Such a laboratory experience exposes a large undergraduate population to several aspects of modern organic synthesis (e.g., chirality, asymmetric catalysis, green chemistry, structure-activity relationships, separations by chiral stationary phase chromatography).

通过这一奖项，化学合成(SYN)计划资助俄亥俄州立大学化学系的T.V.RajanBabu教授探索合成中的催化方法。SYN计划发现特别值得注意的是镍介导的氢乙烯基化转化，以及在上一个循环中发展起来的令人印象深刻的区域发散的Y-Salen介导的氮杂环丙烷开放化学。下一周期研究计划的主要特点包括研究高效的立体选择性氢乙烯基化反应的机理，以及开发一种史无前例的不对称硅基(硼基)锡化-二炔环化反应，该环化反应将得到轴向手性环二烯。在大多数成环反应中，即使是在高度催化和选择性的反应中，官能团的数量通常在从不饱和的起始物质到产物的过程中被耗尽。在上述由不同X-Y试剂(X，Y=[R3Si]，[R3Sn]，[R2b])催化的二炔、烯炔、烯丙炔和丙二烯-醛的环化反应中，反应产物中的官能团数量净增加。此外，在α，omega-diyne环化的情况下，产物(ZZ)-1，2-双亚烷基是轴向手性的，并且这种手性转移到新形成的环周围的手性中心预计将为环化反应中的立体控制增加一个新的维度。这些催化过程是RajanBabu研究小组这一基本绿色化学主题和相关工作的一部分。这一主题延续到本科生的有机教学实验室，在实验室中介绍了一个涉及不对称酮的水相不对称生物催化还原的项目。这样的实验室经验使大量本科生接触到现代有机合成的几个方面(例如，手性、不对称催化、绿色化学、构效关系、手性固定相色谱分离)。