Synthesis of Chiral Dispiro‐Indolinone‐Pyrrolidine‐Imidazolones Using ( <i>R</i> ) or ( <i>S</i> )‐1‐(2,4‐Dimethoxyphenyl)Ethyl Amine

Abstract Chiral dispyrindolinone‐pyrrolidine‐indolinones were obtained using a four‐step synthetic sequence: (1) preparation of thioureas and 5‐arylidene‐thiohydantoins from ( R ) or ( S )‐1‐(2,4‐dimethoxyphenyl)ethylamine; (2) 1,3‐cycloaddition reaction of the chiral 5‐arylidene‐thiohydantoins with azomethine ylide to obtain a diastereomers' mixture; (3) diastereomers separation and removing the auxiliary 1‐(2,4‐dimethoxyphenyl)ethyl group.