Organocatalytic Asymmetric Synthesis of 1,2,4-Trisubstituted Azetidines by Reductive Cyclization of Aza-Michael Adducts of Enones
作者:Lal Yadav、Ritu Kapoor、Ruchi Chawla、Santosh Singh
DOI:10.1055/s-0031-1290954
日期:2012.6
aza-Michael addition of N-substituted phosphoramidates to enones generates aza-Michael adducts which undergo intramolecular reductive cyclization with (R)-alpine borane to afford 1,2,4-trisubstituted azetidines in a one-pot procedure. These optically active products are obtained in good to high yields (67–93%) with excellent stereocontrol (78–96% ee) from a vast variety of enones.
N-取代的氨基磷酸酯与烯酮的高效和高度对映选择性有机催化氮杂-迈克尔加成生成氮杂-迈克尔加合物,该加合物与 (R)-高山硼烷进行分子内还原环化,在一锅法中提供 1,2,4-三取代氮杂环丁烷. 这些光学活性产物以良好到高产率 (67–93%) 获得,具有出色的立体控制 (78–96% ee),来自种类繁多的烯酮。