Second cinchona rearrangement

Scheme 12.42 Second cinchona rearrangement. Effect of a change to O-mesylated cinch base (6 -R = H) and solventtrifluoroethanol.

The [2.2.2]azabicyclic cage of the alkaloids is not immutable. The first and second cage expansions have been discovered only during the past decade. A general cinchona alkaloid solvolysis and rearrangement scheme and a unified theory have been presented. Classical solvolysis chemistry with conventional hydrocarbon substrates is complemented. The resulting azabicyclo[3.2.2]nonanes have hardly been studied. 

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