Diastereoface Selectivity During Pthalimidonitrene Additions to (E)-and (Z)-configurated ?, ?-unsaturated esters, induced by a chiral center in the ?-position
作者:Zdzislaw Chilmonczyk、Markus Egli、Christoph Behringcr、Andr�S. Dreiding
DOI:10.1002/hlca.19890720528
日期:1989.8.9
ribo-, and lyxo- configuration, respectively, by X-ray structure analysis of 2b, 2d, and 6a. The diastereoface selectivity of the nitrene additions, induced by the chiral substructure around C(γ), resulted in more 2 than 3 from 1, but more 6 than 5 from 4, which means that the preference of attack at the double bond switches from one side to the other depending on the C=C configuration. The preferences
在-原位-生成phthalimidonitrene加入到5个α,含有一个手性仲O形函数β -不饱和酯Ç(γ)。加料完全suprafacial,因为在(E) -异构体1得到只反-aziridines 2和3 (j(β,γ) = 4.8-5.1赫兹)和(Z) -异构体4仅顺-氮丙啶5和6(8.2-8.5 Hz)。该产品2,3,5,和6,其中显示具有阿拉伯- ,低聚木糖- , -核糖- ,和来苏-构型,分别由X射线结构分析图2b,2d中,与图6a。所述的diastereoface选择性氮烯的添加,通过围绕C(γ)的手性亚结构诱导,导致更多的2比3从1,但更6比5从4,这意味着攻击中的双键的偏好从一个切换侧取决于C = C配置。在较低的温度下偏好更高。氮丙啶2a,2d和3d在环N-原子处显示出1 H-NMR-可见的异构体。主要的(78-95%)invertomer甲始终是具有在邻苯二甲酰亚胺基团的