A catalyst-free water-mediated regio- and stereospecific ring-opening reaction of nonracemic spiroaziridine oxindoles and indoles has been developed with retention of configuration. This method provides direct access to enantiopure 3,3'-mixed bisindoles with excellent yield and enantioselectivity (up to 98% ee).

Chiral BOX-Cu(OTf)2 catalyzed enantioselective aminolactonization of the tert-butyl ester of alkenoic acids has been developed via in situ aziridination using PhINNs as the nitrene source. It provides exclusively trans-γ- and δ-amino lactones including an additional all-carbon quaternary stereo-centre with up to 98% ee in good to excellent yields.

A general and direct strategy for the synthesis of chiral spiro-aziridine oxindoles has been developed via an aza-Corey-Chaykovsky reaction of isatin-derived N-tert-butanesulfinyl ketimines with excellent selectivity (dr = 98:2 to >99:1). The method is explored for the synthesis of chiral 3-substituted spiro-aziridine oxindoles with high (2S,3S)-selectivity over (2S,3R).