1,3-Asymmetric Induction in Diastereoselective Allylations of Chiral <i>N</i>-Tosyl Imines
作者:Anna Lo、David A. Gutierrez、Garrett Toth-Williams、James C. Fettinger、Jared T. Shaw
DOI:10.1021/acs.joc.1c02691
日期:2022.3.4
Lewis acid mediated allylations of β-alkoxy N-tosyl imines using allyltrimethylsilane lead to 3-alkoxy homoallylic N-tosyl amines with anti-selectivity. Two methods of Cu(OTf)2-mediated allylations are reported herein, demonstrating that diastereoselectivity can be achieved through 1,3 acyclic stereocontrol of β-chiral aldimines. Observed selectivity trends and computational evidence suggest selectivity
使用烯丙基三甲基硅烷的路易斯酸介导的 β-烷氧基N-甲苯磺酰基亚胺烯丙基化产生具有反选择性的 3-烷氧基高烯丙基N-甲苯磺酰基胺。本文报道了两种 Cu(OTf) 2介导的烯丙基化方法,证明非对映选择性可以通过 β-手性醛亚胺的 1,3 无环立体控制来实现。观察到的选择性趋势和计算证据表明选择性是通过形成六元环螯合物而产生的。这些烯丙基化的产物比率取决于过渡态结构中螯合物的构象偏好和空间效应。