Regioselective Deuteration of a 3,4‐Dialkoxypyrroline N‐Oxide and Synthesis of 8a‐d‐Indolizidines

Abstract

A simple and efficient method for C‐2 deuterium labeling of 3,4‐di‐tert‐butoxypyrroline N‐oxide, a useful chiral building block in azaheterocycles syntheses, is presented. Selective and quantitative deuterium incorporation (> 99 %) was achieved by base‐catalyzed H/D exchange in D2O under mild reaction conditions. A mechanistic pathway based on kinetic and computational data was proposed. The labeled nitrone was used in the synthesis of C‐8a deuterated (1R,2R,8aR)‐lentiginosine.