Synthesis of (1R,2R)-DPEN-derived triazolium salts and their application in asymmetric intramolecular Stetter reactions.

A series of novel chiral triazolium salts has been synthesized from readily available (1R,2R)-DPEN and found to be efficient for the enantioselective intramolecular Stetter reaction. With 10 mol% of the catalyst, the intramolecular Stetter reaction was realized in excellent yields with up to 97% ee.