Formation of non-racemic tricyclic compounds by intramolecular 1,3-dipolar cycloaddition of nitrones

Article abstract of DOI:10.1016/0040-4039(95)02275-9

3-Oxanitrones 10 and 3-azanitrones 11 were prepared starting from (S)-ethyl lactate 5 and (S)-N-benzyl alaninol 8, respectively. Both nitrones underwent spontaneously an intramolecular cycloaddition affording the tricyclic compounds 12 and 13. The diastereomeric forms of 12 and of 13 were separated by column chromatography and identified by NMR spectroscopy.