Synthesis of α-Aryl Oxindoles by Friedel–Crafts Alkylation of Arenes
Balaji V. Rokade, Patrick J. Guiry
Abstract
α-Aryl oxindoles are accessed from isatin via a two-step procedure involving a phospha-Brook rearrangement and a Friedel-Crafts alkylation in a one-pot procedure. The use of 1,1,1,3,3,3-hexafluoro-2-propanol as solvent significantly extended the reaction substrate scope to include relatively less electron-rich arenes including benzene. This new alkylation method is fast and straightforward and allows for the direct introduction of the oxindole moiety onto a range of aromatic compounds including phenols. Additionally, the application of arylated products was shown in decarboxylative asymmetric allylation and protonation.
Topics & Concepts
ChemistryFriedel–Crafts reactionAlkylationArylMoietyOrganic chemistryProtonationElectrophilic aromatic substitutionBenzeneOxindoleCombinatorial chemistryAlkylCatalysisIonAsymmetric Synthesis and CatalysisSynthetic Organic Chemistry MethodsAdvanced Synthetic Organic Chemistry