Ruthenium-Catalyzed Asymmetric Allylic Alkylation of Isatins

Abstract

A new ruthenium-based catalytic system for branched-selective asymmetric allylic alkylation is disclosed and applied to the synthesis of chiral isatin derivatives. The catalyst, which is generated <i>in situ</i> from commercially available CpRu(MeCN)₃PF₆ and a BINOL-derived phosphoramidite, is both highly active (TON up to 180) and insensitive to air and moisture. Additionally, the <i>N</i>-alkylated isatins accessible using this methodology are versatile building blocks that are readily transformed into chiral analogs of achiral drug molecules.