Pyrrolizidine synthesis via N-chloroamine rearrangements

A model system was investigated for its potential applicability toward pyrrolizidine diol synthesis via silver ion induced rearrangement of appropriately substituted N-chloroazabicyclo[4.2.0]-octanes. The results clearly show that this synthetic route is possible.

Attendant to this work was the demonstration that stereospecific modification of a single bicyclic ketoester into a series of diols of differing stereochemistries could be accomplished in high yield. Analogous treatment of compounds with the appropriate regiochemical and stereochemical relationships should provide the naturally occurring necine bases upon rearrangement. That systems of this type are available synthetically was also demonstrated.