Origins of Selectivity in Brønsted Acid-Promoted Diazoalkane−Azomethine Reactions (The Aza-Darzens Aziridine Synthesis)

Abstract

The mechanism of the Brønsted acid-catalyzed aza-Darzens reaction is explored by charting the stereochemical outcome of the triflic acid-promoted conversion of trans-triazolines to cis-aziridines. These experiments are consistent with the intermediacy of an α-diazonium-β-amino ester intermediate.