Asymmetric Double Oxidative [3 + 2] Cycloaddition for the Synthesis of CF3-Containing Spiro[pyrrolidin-3,2'-oxindole]

Org Lett. 2023 May 5;25(17):3152-3156. doi: 10.1021/acs.orglett.3c01083. Epub 2023 Apr 21.

Abstract

An asymmetric double oxidative [3 + 2] cycloaddition is reported. Oxidation of 3-((2,2,2-trifluoroethyl)amino)indolin-2-ones and β-aryl-substituted aldehydes simultaneously and subsequent asymmetric cycloaddition in the presence of the chiral amino catalyst generated highly functionalized chiral CF3-containing spiro[pyrrolidin-3,2'-oxindole] with four contiguous stereocenters stereoselectively, which is characterized by directly constructing two C-C bonds from four C(sp3)-H bonds. This new method features mild conditions, broad substrate scope, and excellent functional group compatibility.