Diastereo- and Enantioselective Synthesis of Polyfunctional Cyclic Ketones with Neighboring Quaternary and Tertiary Stereogenic Centers via [2,3]-Wittig Rearrangement
作者:Dieter Enders、Michael Bartsch、Dirk Backhaus、Jan Runsink、Gerhard Raabe
DOI:10.1055/s-1996-4412
日期:1996.12
The diastereo- and enantioselective synthesis of β-substituted γ,δ-unsaturated cyclic α-hydroxy ketones 4 with neighboring quarternary and tertiary stereogenic centers via asymmetric [2,3]-Wittig rearrangement of SAEP-hydrazones 2 with good overall yields (58-74%), high anti-selectivities (92-94%) and excellent enantiomeric excesses (ee ≥ 96%) is described. The absolute configuration is determined by X-ray structure analysis of the hydrazone 3b and by 1H NMR NOE measurements.
介绍了通过 SAEP-hydrazones 2 的不对称 [2,3]-Wittig 重排,非对映地和对映体选择性地合成具有邻近四元和三元立体中心的δ²-取代δ³,δ-不饱和环状δ-羟基酮 4 的方法,该方法具有良好的总收率(58-74%)、高反选择性(92-94%)和优异的对映体过量(ee ≥ 96%)。通过对腙 3b 的 X 射线结构分析和 1H NMR NOE 测量确定了其绝对构型。