Synthesis of (2<i>R</i>,5<i>R</i>)‐5‐Chloropipecolic Acid via a Homochiral Acyliminium Ion Intermediate

Abstract

Abstract An efficient synthesis of (2 R ,5 R )‐5‐chloropipecolic acid hydrochloride ( 11 ) is described, starting from the readily available methyl ( S )‐5‐( tert ‐butyldimethylsilyloxy)‐2‐oxopiperidine‐1‐carboxylate ( 3 ).