Asymmetric Organocatalytic Access to Spiro-fused Heterocyclic Compounds: E1cB Elimination Mediates Formal [4 + 2] Annulation
作者:Zhi-Hao You、Yan-Kai Liu
DOI:10.1021/acs.orglett.2c02435
日期:2022.9.2
synthesis of polycyclic compounds which contained both chromane and spirooxindole moieties. In the reaction, regardless of the competitive pathways resulting from multireactive sites of starting materials, products could be obtained in good yields (up to 84%) and with excellent enantioselectivities (most 98 to >99% ee) under the catalysis of a chiral bifunctional thiourea-tertiary amine (1–5 mol %)
基于分子内E1cB消除,设计了一种新颖的[4 + 2]环化方法,并成功应用于不对称合成含有色烷和螺氧吲哚部分的多环化合物。在该反应中,无论起始材料的多反应位点导致的竞争途径如何,在手性双官能团的催化下,都可以以良好的收率(高达 84%)和优异的对映选择性(大多数 98 至 >99% ee)获得产物硫脲-叔胺 (1–5 mol %)。