Asymmetric Synthesis Using N-O Compounds.

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DESCRIPTION (provided by applicant): This research proposal describes the development of an efficient asymmetric catalysis based on the new chemistry of N-O compounds. The research will be directed towards three goals. The first goal will be to design a metal catalyst for a truly useful and practical asymmetric oxidation of olefinic alcohols, alkenes, sulfides, and phosphines. The method heavily depends on our previous observations of vanadium asymmetric epoxidation catalyst for which unique hydroxamic acid libraries were developed. We intend to synthesize a number of new hydroxamic acid ligand libraries and evaluate them for enantioselectivity and reactivity in vanadium-catalyzed asymmetric epoxidation. The second theme will focus on selective synthesis of new hydroxyamino and aminooxy carbonyl compounds. Using simple nitroso starting materials in the presence of Lewis acid catalysts, various carbonyl compounds could be converted to new hydroxyamino and aminooxy derivatives. Furthermore, with this approach, asymmetric catalytic introduction of oxygen and nitrogen functional groups alpha to carbonyl compounds will be obtained and used as a key synthetic reaction useful for chiral natural and unnatural product synthesis. The third effort will be to develop new asymmetric protonation in alcoholic solvents using metal catalysts with hydroxamic acid and related N-O ligand libraries. Efficient asymmetric protonation of racemic carbonyl compounds is an important synthetic transformation, which has not been developed to a useful level. Overall, all of these goals are expected to result in not only the development of highly efficient catalytic asymmetric synthesis but also the development of new methods and concepts that should provide a number of useful organic synthesis endeavors as well as new entry into various N-O compounds, which biologically are a highly important class of molecules.