Manganese-Catalyzed Epoxidations of Alkenes in Bicarbonate Solutions
Benjamin S. Lane, Matthew Vogt, Victoria J. DeRose and Kevin Burgess*
*Department of Chemistry, Texas A & M University, P.O. Box 30012, College Station, Texas 77842-3012, Email: burgesstamu.edu
B. S. Lane, M. Vogt, V. J. DeRosa, K. Burgess, J. Am. Chem. Soc., 2002, 124, 11946-11954.
DOI: 10.1021/ja025956j (free Supporting Information)
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An epoxidation of alkenes using hydrogen peroxide as the terminal oxidant is promoted by catalytic amounts (1.0-0.1 mol %) of manganese(2+) salts, and must be performed using at least catalytic amounts of bicarbonate buffer. Various aryl-substituted, cyclic, and trialkyl-substituted alkenes were epoxidized under these conditions using 10 equiv of hydrogen peroxide, but monoalkyl-alkenes were not. Additives such as sodium acetate and salicylic acid enhanced the rate of the desired epoxidation reaction by 2-3 times. Possible mechanisms for the reaction are discussed.
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