Iron(III)-Catalyzed (4 + 2)-Cycloannulation of 2-Hydroxy Ketoxime Ethers with Indol-2-ylamides: Synthesis of Indole-Fused 2-Piperidinones
作者:Marcel Schlegel、Christoph Schneider
DOI:10.1021/acs.joc.9b00261
日期:2019.5.3
A highly regio- and diastereoselective (4 + 2)-cycloannulation process of indanone-derived 2-hydroxy ketoxime ethers with 1,4-bisnucleophilic indol-2-ylamides has been developed. In the presence of 5 mol % FeCl3, densely functionalized 2-piperidinones containing two new σ-bonds and two vicinal quaternary stereogenic centers were formed under mild reaction conditions in a one-pot operation. Moreover
已开发出由茚满酮衍生的2-羟基酮肟醚与1,4-双亲核吲哚-2-基酰胺的高度区域选择性和非对映选择性(4 + 2)-环环化工艺。在5 mol%FeCl 3的存在下,在一锅操作中,在温和的反应条件下,形成了含有两个新的σ键和两个相邻的季铵立体构型中心的稠密官能化的2-哌啶酮。而且,大多数产物直接从溶液中沉淀出来,并通过简单过滤分离而无需通过柱色谱法纯化。