High pressure liquid chromatography for the analysis of enantiomerically enriched products

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The equipment requested in this grant is a high-pressure liquid chromatography system with the capability of performing enantiomer separation. This instrument will be used to analyze the enantiomeric composition of chiral compounds prepared using organocatalytic methods.    Asymmetric catalysis using organic molecules (organocatalysis) has recently emerged as a powerful approach for the synthesis of organic compounds in an enantioselective fashion. Despite the great advances accomplished in this area, most methods developed so far show a narrow scope of reagents. Also, the catalysts reported thus far show very little variety in their scaffold and the nature of their catalysis. The purpose of this research is to develop new classes of organocatalysts and new catalytic modes of action that will complement and expand existing methodology. In order to achieve these goals, three different areas will be explored: asymmetric phase transfer catalysis, multifunctional catalysis, and Lewis base-catalyzed Diels-Alder reactions.    In the first part of the program, phase transfer catalysts possessing novel scaffolds will be synthesized in order to broaden the scope and to improve the stability of this type of catalysts. In the area of multifunctional catalysis, various types of activating groups, such as substituted guanidines, will be introduced. These groups will display increased reactivity as well as the ability to tune their activity through the judicious choice of their substituents. Finally, the application of Lewis base catalysts to the Diels-Alder reaction will dramatically expand the scope of available reactive partners for this very important reaction. In particular, it will allow the use of a wide variety of functionalized dienes that are incompatible with commonly used Lewis acid catalysts.    The underlying theme of this research program is the asymmetric synthesis of useful chemical building blocks using organic molecules as catalysts. In order to assess the efficiency of these catalytic processes, the use of chiral high-pressure liquid chromatography will be essential.