Catalytic Asymmetric 1,2-Difunctionalization of Indolenines with α-(Benzothiazol-2-ylsulfonyl) Carbonyl Compounds

A novel catalytic asymmetric 1,2-difunctionalization reaction of indolenines with alpha-(benzothiazol-2-ylsulfonyl) carbonyl compounds was developed. By employing the strategy of Bronsted acid-assisted chiral phosphoric acid catalysis, the Mannich addition/Smiles rearrangement cascade occurred smoothly and provided a new family of optically active 1,2-difunctionalized 2-substituted indolines in good yields and enantioselectivities.