Enantioselective syntheses and X-ray structures of (S)- and (R)-N-norlaudanidine: trace opium constituents

The enantioselective synthesis of each of the enantiomers of N-norlaudanidine, a minor Papaver somniferum opium benzyltetrahydoisoquinoline alkaloid is described. This was achieved using a chiral auxiliary-mediated Bischler–Napieralski cyclization-sodium borohydride reduction strategy. The X-ray crystal structures of each of these secondary amines are reported.