Highly efficient synthesis and stereoselective migration reactions of chiral five-membered aza-spiroindolenines: scope and mechanistic understanding

Chem Sci. 2016 Jul 1;7(7):4453-4459. doi: 10.1039/c6sc00176a. Epub 2016 Mar 29.

Abstract

An Ir-catalyzed asymmetric synthesis of five-membered aza-spiroindolenines is achieved. Based on the detailed investigation of the reaction patterns of the aryl iminium migration, a one-pot asymmetric allylic dearomatization/migration sequence from racemic indole derivatives is realized, affording enantioenriched Pictet-Spengler-type products bearing an additional allylic stereogenic center adjacent to the C3 position of the indole core.