ORGANIC SYNTHESIS REAGENTS BASED ON TRANSITION METALS

拟议研究的基本目标是开发新的 允许合成络合物的试剂和合成策略 具有生物学意义的有机分子和聚合物。一个家庭 含有金属-碳双键并具有活性的络合物 用于烯烃歧化反应的催化剂现已问世。这些复合体 展示一系列活动和功能群体容忍度。这些复合体 已被证明在合成各种环状化合物中是有用的 烯烃是合成生物活性分子的关键中间体。 现在可用的设计原则和技术将是 旨在将这些催化剂用于选择性地 开环烯烃的立体选择性合成及其开发 用于手性烯烃的动力学拆分的手性络合物 用于三烯烃的不对称环化反应。战略也在进行中 开发出了聚醚和聚醚的模块化合成 多肽的选择性合成(包括固体载体上和载体上的) 使用受约束的几何图形。为了达到许多综合目标，新的 将制备含有空间不对称的催化剂以诱导 所需的双键几何构型，用于转化的水溶性配体 用于不对称诱导的水溶性底物和手性配体 在C-C键形成过程中。所有这些研究都利用了 在室温下形成并裂解碳-碳双键 在存在各种官能团的情况下处于中性状态。

The basic objective of the proposed research is the development of new reagents and synthetic strategies that allow the synthesis of complex organic molecules and polymers that are of biological interest. A family of complexes that contain metal-carbon double bonds and are active catalysts for the metathesis of olefins is now available. These complexes show a range of activities and functional group tolerance. These complexes have been demonstrated to be useful in the synthesis of a variety of cyclic olefins that are key intermediates in the synthesis of bioactive molecules. The design principles and techniques that are now available will be directed toward the use of these catalysts for the selective stereoselective synthesis of acyclic olefins and for the development of chiral complexes to be used in the kinetic resolution of chiral olefins and for the asymmetric cyclization of triolefins. Strategies are also being developed that will allow the modular synthesis of polyethers and the selective synthesis of polypeptides (both on and off of solid supports) with constrained geometries. To reach many of the synthetic goals, new catalysts will be prepared that contain steric asymmetries to induce desired double bond geometries, water soluble ligands for the conversion of water soluble substrates, and chiral ligands for asymmetric induction during C-C bond formation. All of these studies exploit the ability to form and cleave carbon-carbon double bonds at room temperature under neutral conditions in the presence of a wide variety of functional groups.