Identification des configurations Z et E en série cyclopropylidénique. Stéréosélectivité de la migration exocyclique de la double liaison cyclopropénique en milieu basique
作者:M. Vincens、C. Dumont、M. Vidal
DOI:10.1016/s0040-4020(01)98975-6
日期:1981.1
The identification of E- and Z-2-alkyl-3-ethylidenecyclopropane having a functional group (ketone, ester, alcohol) at C-1 of the ring, is realized by chemical means and by NMR induced shifts using Eu(dpm)3. These structure assignments show that the cyclopropene ester, ketone, alcohol double bond migration in basic media leads preferentially to the E-configuration; the stereoselectivity may reach 90%
通过化学方法和使用Eu(dpm)3的NMR诱导的位移,可以识别在环的C-1处具有官能团(酮,酯,醇)的E-和Z -2-烷基-3-亚乙基亚环丙烷。这些结构分配表明,在碱性介质中环丙烯酯,酮,醇双键迁移优先导致E-构型。立体选择性可能达到90%。此外,与环相比,原生质是区域特异性和立体特异性的。