Organocatalytic Enantioselective aza‐Friedel‐Crafts Reactions of Pyrazolinone Ketimines with Hydroxyindoles and Electron‐Rich Phenols

Abstract A variety of enantioenriched indole derivatives substituted in the benzene ring were synthesised via an organocatalytic asymmetric aza‐Friedel‐Crafts reaction of pyrazolinone ketimines with hydroxyindoles. This reaction was also applicabled to electron‐rich phenols, yielding the desired products in high yields (up to 99%) and excellent stereo‐selectivities (91–99% ee). Moreover, this method presents its potential in the synthesis of structurally novel indole‐pyrazolinone conjugate derivatives. magnified image