An efficient Lewis acid induced nitrogen-driven rearrangement iminium-trapping cascade from an epoxytropinone 3 gives a 7-allylated 6-azabicyclo[3.2.1]octan-3-one 2, which is converted into the alkaloid (+/-)-peduncularine (1).

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Epoxide Opening-Induced Tandem 8-Azabicyclo[3.2.1]octane to 6-Azabicyclo[3.2.1]octane Rearrangement-Iminium Allylation: Synthesis of (±)-Peduncularine. -The rearrangement of (I) is promoted by TmsOTf and affords (III) in high yield. The product is further transformed into the target alkaloid (±)-peduncularine (IV) in 13 steps and 5% yield. -(HODGSON*, D. M.; SHELTON, R. E.; MOSS, T. A.; DEKHANE, M.; Org. Lett. 12 (2010) 12, 2834-2837, DOI:10.1021/ol100943j ; Dep. Chem., Univ. Oxford, Oxford OX1 3TA, UK; Eng.) -R. Steudel 45-199