Asymmetric synthesis of piperidines and octahydroindolizines using a one-pot ring-closure/ N-debenzylation procedure

The conjugate addition of an enantiopure lithium amide to a ζ-hydroxy-α,β-unsaturated ester followed by a one-pot ring-closure/N-debenzylation protocol has been used in the asymmetric syntheses of ( S)-coniine and ( R)-δ-coniceine (isolated as the corresponding hydrochloride salts), and ( R, R)-1-(hydroxymethyl)octahydroindolizine (the bicyclic fragment of stellettamides A–C). A one-pot ring-closure/N-debenzylation protocol has been used in the asymmetric syntheses of ( S)-coniine, ( R)-δ-coniceine, and ( R, R)-1-(hydroxymethyl)octahydroindolizine (the bicyclic fragment of stellettamides A–C). [Display omitted]