Synthesis of piperidine derivatives fused to a tetrahydrofuran ring

This is the authors' abstract. We don't add key points for this paper.

Intramolecular nucleophilic opening of the oxirane ring in tert -butyl 6-(2-hydroxyethyl)-7-oxa-3-azabicyclo[4.1.0]heptane-3-carboxylate by the action of excess potassium hydroxide in 75% aqueous dimethyl sulfoxide at 110–120°C gave tert -butyl (3a R ,7a S )-3a-hydroxyhexahydrofuro[2,3- c ]pyridine-6(2 H )-carboxylate whose treatment with POCl 3 resulted in elimination of water molecule and tert -butoxycarbonyl group with formation of 2,3,4,5,6,7-hexahydrofuro[2,3- c ]pyridine hydrochloride. The latter reacted with electrophiles (acetic anhydride, methanesulfonyl chloride, and benzaldehyde in combination with sodium triacetoxyhydridoborate) in the presence of triethylamine, yielding the corresponding N-substituted 2,3,4,5,6,7-hexahydrofuro[ 2,3- c ]pyridine derivatives.