Asymmetric Aldol Reaction of Ketones with Alkenyl Trichloroacetates Catalyzed by Dibutyltin Dimethoxide and BINAP⋅Silver(I) Complex: Construction of a Chiral Tertiary Carbon Center
作者:Akira Yanagisawa、Yuuki Terajima、Kazuma Sugita、Kazuhiro Yoshida
DOI:10.1002/adsc.200900437
日期:2009.8
The reaction was found to be remarkably accelerated by the addition of a catalytic amount of a bidentate phosphine⋅silver(I) complex. Use of the BINAP⋅silver triflate (AgOTf) complex as the chiral co-catalyst resulted in the formation of optically active aldol products possessing a chiral tertiary carbon with up to 93% ee. This catalytic method was further applied to the asymmetric reaction of diketene
Highly Enantioselective Reactions of Cyclohexanone and<i>β</i>,<i>γ</i>-Unsaturated<i>α</i>-Keto Ester: The Tuning of Chemo-selectivities by Secondary and Primary Amine Catalysts
作者:Jianwei Wei、Wengang Guo、Xin Zhou、Xin Du、Yan Liu、Can Li
DOI:10.1002/cjoc.201400431
日期:2014.10
amphiphilic imidazole based secondary and primaryaminecatalysts were synthesized and shown to be very effective with an acid cocatalyst for the asymmetric reaction of cyclohexanone to β,γ‐unsaturated α‐keto ester. Interestingly, primary and secondaryaminecatalysts show different regio‐selectivities in this reaction. Under the catalysis of secondaryamine 1, excellent enantioselectivities were observed for