Enantioselective synthesis of 2-arylpiperidines from chiral lactams. A concise synthesis of (–)-anabasine

Cyclodehydration of achiral or racemic aryl-δ-oxoacids with (R)-phenylglycinol stereoselectively affords chiral non-racemic bicyclic lactams, from which the enantiodivergent synthesis of (R)- and (S)-2-phenylpiperidine, the diastereodivergent synthesis of cis- and trans-3-ethyl-2-phenylpiperidine, and the enantioselective synthesis of the piperidine alkaloid (−)-anabasine is reported.