Expeditious Synthesis of Enantioenriched Tetrahydropyrans <i>via</i>
Chemoselective <i>C−N</i>
bond Cleavage of Aza-Oxa-Bicyclo[3.2.1]Octanes
作者:Cecilia Sasso D'Elia、Sébastien Goudedranche、Thierry Constantieux、Marco Bella、Damien Bonne、Jean Rodriguez
DOI:10.1002/adsc.201700735
日期:2017.10.25
between ambident electrophilic and 1,4‐bis‐nucleophilic 1,2‐ketoamides and 1,3‐bis‐electrophilic enals, leading to aza‐oxa‐bicyclo[3.2.1]octane. Then, the TiCl4/Et3SiH system ensures a chemoselective cleavage of the C−N bond and affords the desired trisubstituted tetrahydropyran in good yield and with conservation of the precursors optical purity. This final synthetic operation includes two consecutive
据报道,快速合成对映体富集的2,3,4-三取代的四氢吡喃具有良好的收率和立体选择性。第一步是环境亲电子和1,4-双亲核1,2-酮酰胺和1,3-双亲电子烯醛之间的多米诺有机催化反应,形成氮杂-氧杂双环[3.2.1]辛烷。然后,TiCl 4 / Et 3 SiH系统确保C-N键的化学选择性裂解,并以高收率提供所需的三取代四氢吡喃,并保留了前体的光学纯度。该最终合成操作包括两个连续的氧碳鎓离子形成和还原。