ORGN 512 |
| Metal-catalyzed epoxidation of alkenes is of significant interest from bothe academics and industry. Although numerous methods have been developed, more efficient, selective, and practical riutes are still highly required to include more wide range of substrates. In this presentation, we show that manganese clusters with certain kinds of organic ligands can be employed as a highly efficient catalysts for the epoxidation of various types of alkenes. Especially, ligands of simple structure such as pyridinyl imine appeared to be extremely effective moiety for achieving high degree of success. In solid structure, the ligand and maganese form 2:3 ratio of cluster and the Mn3L2 complex can be used as a catalyst precursor. The epoxidation proceeds highly efficiently under mild conditions to afford the desired epoxides in good to excellent yields. A variety of kinetic studies have suggest that the reaction is first order to catalyst and zeroth order to alkene substrates. In addition, the data reveals that it takes place presumably via a radical intermediacy. |
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New Reactions, Methodology, Total Synthesis, Physical Organic Chemistry
8:00 PM-10:00 PM, Tuesday, 15 March 2005 Convention Center -- Sails Pavilion, Poster
Division of Organic Chemistry |