De novo construction of chiral 3‑oxindoles via organocatalyzed enantioselective ortho-Friedel-Crafts addition/novel [1,2]-ester migration

Abstract

The de novo construction of chiral 3-hydroxyindolenines and 3-oxindoles from easily available starting materials has been highly desired. Meanwhile, the intermolecular enantioselective ortho-C-H addition to ketone carbonyl remains a long-standing challenge. Herein, an unprecedent enantioselective intermolecular direct ortho-Friedel-Crafts addition of primary aryl amine with 2,3-diketoesters to construct 3-hydroxyindolenines with a chiral tertiary alcohol has been disclosed. The following unusual [1,2]-ester migration provides a family of chiral 3-oxindoles in good to excellent yields with excellent enantio-selectivity.

Catalytic Asymmetric Cyclizative Rearrangement of Anilines and Vicinal Diketones to Access 2,2‐Disubstituted Indolin‐3‐ones

“…On the other hand, as specific aromatic amines, the more nucleophilic α‐ and β‐naphthylamines with fixed ortho ‐nucleophilic‐site have been used as 1,3‐binucleophiles for few enantioselective cyclization reactions. [ 17 , 18 ] We report herein the successful realization of this endeavor via chiral phosphoric acid catalyzed CACR of diverse anilines and vicinal diketones using a simple procedure, which provides a modular and general synthesis of 2,2‐disubstituted indolin‐3‐ones in a high level of yield and enantiopurity (Scheme 1D ). Mechanistic studies as well as further synthetic transformations of the resulting products were also performed.…”