Catalytic asymmetric darzens condensation in the presence of bovine serum albumin.
作者:Rita Annunziata、Stefano Banfi、Stefano Colonna
DOI:10.1016/s0040-4039(00)94856-1
日期:1985.1
Darzenscondensation of aromatic aldehydes with phenacyl halides in the presence of a catalytic amount of bovine serum albumin afforded the corresponding epoxyketones in up to 62% e.e.
A highly enantioselective asymmetric Darzens reaction catalysed by proline based efficient organocatalysts for the synthesis of di- and tri-substituted epoxides
A new class of easily available and readily tunable proline based chiral organocatalysts was found to efficiently catalyse an unprecedented highly enantioselective asymmetric Darzens reaction of α-chloro ketones and substituted α-chloro ketones with various aldehydes, which directly produces optically active di- and tri-substituted chiral epoxides with higher product yields (up to 97 %) and excellent
Solvent microstructure effect on reaction stereochemistry; ring opening of chalcone oxides
作者:Dana Durham、Charles A. Kingsbury
DOI:10.1039/p29860000923
日期:——
The stereochemistry and kinetics of acid-catalysed ring-opening reactions of epoxides are reported. Predominant inversion is found in the usual hydroxylic solvents. As the nucleophilicity of the solvent diminishes and acidity increases, the stereochemistry changes to predominant retention. Electron-donating substituents also tend to favour retention. In mixed solvents, the solvent microstructure is
1,1,2,2‐Tetrahydroperoxy‐1,2‐diphenylethane was used for the efficient and metal‐free epoxidation of various α,β‐unsaturated ketones, carried out under mild alkaline conditions at room temperature.
Facile epoxidation of α, β-unsaturated ketones with urea-2,2-dihydroperoxypropane as a new oxidant
作者:Kaveh Khosravi、Shirin Naserifar
DOI:10.1007/s13738-016-0980-1
日期:2017.2
AbstractVarious aromatic α, β-unsaturatedketones were successfully transformed into their corresponding epoxides using urea-2,2-dihydroperoxypropane as the oxygen source for the first time. The reactions were carried out under mild alkaline conditions at room temperature in high yields and short reaction times. Graphical Abstract