Manganese Compounds
Name Reactions
Recent Literature
An effective epoxidation of lipophilic alkenes using hydrogen peroxide was
accomplished with a manganese sulfate/bicarbonate catalytic system in an ionic
liquid at room temperature.
K.-H. Tong, K.-Y. Wong, T. H. Chan, Org. Lett., 2003, 5,
3423-3425.
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.
B. S. Lane, M. Vogt, V. J. DeRosa, K. Burgess, J. Am. Chem. Soc., 2002,
124, 11946-11954.
Readily available Mn(III) complexes catalyze alkene epoxidation by bleach in
good yields. A highly enantioselective epoxidation catalyst was developed
through a logical sequence of ligand modifications.
E. N. Jacobsen, W. Zhang, A. R. Muci, J. R. Ecker, L. Deng, J. Am. Chem.
Soc., 1991,
113, 7063-7064.
The complex [MnII(R,R-mcp)(CF3SO3)2]
is a very efficient and practical catalyst for the epoxidation of a wide
scope of olefins including terminal, tertiary, cis and trans
internal, enones, and methacrylates using peracetic acid as the terminal
oxidant.
A. Murphy, G. Dubois, T. D. P. Stack, J. Am. Chem. Soc., 2003,
125, 5250-5251.
Mn(OAc)3 based regioselective oxidation of various 2-cyclopentenone, 2-cyclohexenone
and aromatic ketone derivatives in benzene afforded the corresponding
tertiary α'-acetoxy oxidation products in good yields.
C. Tanyeli, C. Iyiguen, Tetrahedron,
2003,
59, 7135-7139.
