Sn-Li exchange and 'poor man's Hoffmann tests' establish asymmetric trapping of alpha-lithio-N-(tert-butoxythiocarbonyl) (Botc) azetidine to be controlled by dynamic thermodynamic resolution or dynamic kinetic resolution, depending on the electrophile. Unusually, different configurational stability is seen for the anion generated by lithiation compared to transmetallation. Configurational stability of alpha-lithio-N-Boc azetidine indicates instability with theN-Botc system is due to the CS group.
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