Enantioselective Synthesis of Aminoindan Carboxylic Acid Derivatives by the Catalytic Intramolecular [2+2+2] Cycloaddition of Amino-Acid-Tethered Triynes

The enantioselective synthesis of aminoindan carboxylic acid (Aic) derivatives was achieved by Rh-catalyzed intramolecular [2+2+2] cycloaddition of amino-acid-tethered triynes. This reaction, along with recrystallization, gave chiral tethered Aic derivatives with excellent enantiomeric excess. Subsequent hydrolysis of the tethered Aic compounds afforded chiral Aic derivatives, which were further transformed into a free Aic and its dimethyl ester in good yields.