Palladium-catalyzed asymmetric allylic alkylation of 3-amino-2-oxindoles: Synthesis of 3-allyl-3-amino-2-oxindoles

• Published in: Tetrahedron letters 2021-10, Vol.82, p.153385, Article 153385
• Main Authors: Kumarswamyreddy, Nandarapu, Jayakumar, Samydurai, Kesavan, Venkitasamy
• Format: Article
• Language: English
• Subjects: 3-Ally-3-amino oxindoles; Asymmetric allylic alkylation; Bi(oxazoline) ligands; Palladium catalyst; Spiropyrrolidine oxindoles
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2021.153385

[Display omitted] •Efficient asymmetric allylic alkylation (AAA) strategy to access chiral 3-allyl-3-amino-2-oxindoles.•Tartrate derived bi(oxazoline)-palladium (II) induce the asymmetric induction.•3-Amino-2-oxindoles used as prochiral nucleophile.•Metal-free intramolecular iodocyclization to enable chiral spiro-pyrrolidine-2-oxindoles. Tartrate derived bi(oxazoline) ligand with palladium (II) species catalyzed asymmetric allylic alkylation reaction to access highly valuable 3-allyl-3-amino-2-oxindoles with vicinal quaternary and tertiary stereocenters in very good yields (up to 91%) and excellent enantioselectivity (up to 98% ee) with moderate to good diastereoselectivity (up to 5:1). The synthetic utility of 3-allyl-3-amino-2-oxindole was further demonstrated to construct spiro(oxindole-3,2′-pyrrolidine) with consecutive one quaternary and three tertiary chiral centers in good stereoselectivity (dr = 8:1 and 80% ee) through metal-free intramolecular iodocyclization reaction.