Bifunctional organocatalyst for methanolytic desymmetrization of cyclic anhydrides: increasing enantioselectivity by
Ho Sik Rho1, Sang Ho Oh, Ji Woong Lee
1Department of Chemistry, Sungkyunkwan University, 300 Cheoncheon, Jangan, Suwon, Gyeonggi, 440-746 Korea.
Chemical Communications (Cambridge, England)
|March 1, 2008
Abstract:
Highly enantioselective methanolysis of meso-cyclic anhydride was achieved with bifunctional organocatalyst containing a quinine-thiourea moiety; unusual concentration, temperature and solvent effects on the enantioselectivity can be explained in terms of a mechanism involving monomer-dimer equilibration of the catalyst.
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