Catalytic asymmetric Pictet-Spengler-type reaction for the synthesis of optically active indolo[3,4-cd][1]benzazepines.

A new strategy has been introduced to develop a catalytic asymmetric Pictet-Spengler-type reaction by replacing the aldehyde with an imine. A range of 4-(2-aminoaryl)indoles smoothly undergo the chiral phosphoric acid catalyzed asymmetric Pictet-Spengler-type reaction with imines at room temperature to give structurally diverse indolo[3,4-cd][1]benzazepines in good to excellent yields and ee.