[Structure: see text] In addition reactions of enecarbamates and enamides, extremely high turnover frequency of the catalyst was observed in comparison with that of silicon enolate addition reactions. This is presumably due to fast transfer of the proton that locates on the nucleophiles.
Core-Structure-Oriented Asymmetric Organocatalytic Substitution of 3-Hydroxyoxindoles: Application in the Enantioselective Total Synthesis of (+)-Folicanthine
作者:Chang Guo、Jin Song、Jian-Zhou Huang、Peng-Hao Chen、Shi-Wei Luo、Liu-Zhu Gong
DOI:10.1002/anie.201107079
日期:2012.1.23
yield and excellent enantioselectivity. This reaction enabled the enantioselective construction of hexahydropyrroloindole skeletons and the first catalytic enantioselective total synthesis of (+)‐folicanthine.
A C2-symmetric nickel diamine complex as an asymmetric catalyst for enecarbamate additions to butane-2,3-dione
作者:John S. Fossey、Ryosuke Matsubara、Paulo Vital、Shū Kobayashi
DOI:10.1039/b505404d
日期:——
Butane-2,3-dione was activated towards nucleophilicaddition of enecarbamates by a series of metal triflate complexes of a C2-symmetric diamine to give stereogenic, aldol-like, t-alcohols, a novel nickel(II) triflate complex was identified as a good catalyst for this asymmetric transformation, and an aquo nickel(II) complex was identified by XRD techniques.