Enantioselective Synthesis of (+)-α-Conhydrine and (-)-Sedamine by L-Proline-Catalysed α-Aminooxylation

An efficient organocatalytic approach to the enantioslective synthesis of two important piperidine alkaloids, namely (+)‐α‐conhydrine (98 % ee) and (–)‐sedamine (95 % ee), by L‐proline‐catalysed α‐aminooxylation of aldehydes has been developed. The strategy involves an intramolecular cyclization to construct the piperidine core. The piperidine ring is a ubiquitous structural motif present in numerous naturally occurring alkaloids and can be frequently recognized in the structures of drug candidates. Conhydrine and sedamine are two such alkaloids, and their enantioselective synthesis has been achieved in good overall yields.