Diastereoselective Construction of the 6-Oxa-2-azabicyclo[3.2.1]octane Scaffold from Chiral alpha-Hydroxyaldehyde Derivatives by the Aza-Prins Reaction

摘要

(R)-2,3-Di-O-benzylglyceraldehyde and N-tosyl homoallylamine undergo aza-Prins cyclization to afford (1R,SS,7S)-7-[(benzyloxy)methy1]-2-tosy1-6-oxa-2-azabicyclo[3.2.1]octane in a highly diastereoselective manner through an unexpected intramolecular nudeophilic attack Our work has opened a new route toward the asymmetric synthesis of 7 -(alkyl or aryl)-6-oxa-2-azabicyclo[3.2.1]octane derivatives from chiral alpha-hydroxyaldehyde derivatives in one step.