Development of New Stereoselective Metal-Catalyzed Organic Reactions

点击翻译按钮获取中文摘要

 DESCRIPTION (provided by applicant): Our ability to synthesize carbon-carbon bonds is integral to accessing the important biological activity of myriad organic molecules. Many valuable therapeutic agents exist in non-racemic form comprised of multiple stereogenic elements. Such characteristics highlight the critical need for new chemical reactions that allow chemists to efficiently prepare organic compounds with high levels of selectivity. The focus of this research program involves the development of new stereoselective metal-catalyzed processes for carbon-carbon bond formation via the addition of 1,1-bimetallic nucleophiles to a number of classes of electrophiles. These studies will lead to strategically alternative C-C bond disconnections that deliver important functional molecules in enantiomerically pure form. Many of the reactions described herein do not have existing catalytic protocols. (1) We will develop practical and robust Cu-catalyzed enantio-and diastereoselective alkylations of carbonyls and their derivatives with alkyl boron-containing reagents; these reactions will lead to the synthesis of a range of acyclic hydroxy- and amino-boronates that cannot be easily accessed by others methods. The value of these methods is increased by the installation of a highly versatile stereogenic C-B bond. (2) We will develop general enantioconvergent Cu-catalyzed processes for the addition of a range of alkyl-, alkenyl-, aryl-, allyl- substituted 1,1-heterobimetallic nucleophiles to electron-deficient alkenes. This reaction technology will lead to more efficient ways to synthesize homoallyl alcohols and amines common chemical structures found in bioactive molecules. (3) Reaction development will also demonstrate that 1,1-bimetallic reagents offer unique approaches to substrate-directed stereoselective catalytic reactions. The new catalysts and catalytic methods developed in this program offer unique and selective routes to the enantioselective synthesis of adaptable molecules. Through applications to concise synthesis of pharmacologically active agents, we will demonstrate the utility of our methods, in addition to identifying their limitations.