Combined Schmidt Rearrangement Cascade Reactions

Domino reactions, which combine sequential transformations in a single pot, can allow the rapid development of complex products from simple starting materials. One design feature required for successful domino process involves control over the order of reaction events. Since Bronsted acids or Lewis acids are required for the initiation of nearly all azido-Schmidt reactions, combining such reactions with other acid-accelerated processes presents a logical starting point for assembling Schmidt-centric tandem reactions. 

Tu and coworkers demonstrated a tandem semi-pinacol/Schmidt rearrangement sequence beginning with certain azido-tethered epoxides. When epoxide 46 was 

8 Schmidt Rearrangements in the Totai Synthesis of Naturai Products 

Although of only modest biological interest, lasubine II (54), has attracted considerable interest from organic chemists for the validation of new methodologies for alkaloid total synthesis. A total synthesis of this target revealed a limitation of the intramolecular 

Schmidt reactions as it pertains to quinolizidine ring systans and led to the development of a workaround involving the photochemical rearrangonent of nitrones.  

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