Asymmetric Synthesis ofα,γ-Substitutedγ-Sultones via Allylation of Chiral Lithiated Sulfonates
作者:Dieter Enders、Wacharee Harnying、Nicola Vignola
DOI:10.1002/ejoc.200300342
日期:2003.10
The first auxiliary controlled asymmetricsynthesis of enantiopure α,γ-substituted γ-sultones via α-allylation of lithiatedsulfonates by using 1,2:5,6-di-O-isopropylidene-α-D-allofuranose as chiral auxiliary is described. The high asymmetric inductions of the α-allylations were reached in good to excellent yields. Successive epimerization-free cleavage of the auxiliary and diastereoselective ring
Diastereoselective Hydrolysis of α,γ-Substituted γ-Sultones in the Asymmetric Synthesis of γ-Hydroxy Sulfonates
作者:Dieter Enders、Wacharee Harnying、Gerhard Raabe
DOI:10.1055/s-2004-815952
日期:——
The hydrolysis of enantiopure α,γ-substituted γ-sultones with water under mild conditions leads to α,γ-substituted γ-hydroxy methyl sulfonates in very good yields and excellent diastereo- and enantiomeric excesses (de, ee ≥ 98%). The reaction proceeds via a SN2 mechanism with inversion of configuration at the attacked γ-carbon atom whose absolute configuration was established by X-ray crystallography.
在温和的条件下用水水解对映体纯的δ±,δ³-取代的δ³-磺酮,可以得到δ±,δ³-取代的δ³-羟基甲基磺酸盐,收率非常高,非对映和对映体过量率非常好(de, ee ≥ 98%)。该反应通过 SN2 机制进行,在被攻击的 δ³ 碳原子上发生构型反转,其绝对构型由 X 射线晶体学确定。