Rh-Catalyzed Hydroformylation-Initiated Bicyclization: Construction of Azabicyclic Systems

Here, we describe
the recent progress toward construction of 1-azabicyclic
structures using a domino hydroformylation double cyclization strategy
of an amide bearing the trisubstituted alkene functionality. The method
provides a rapid and atom-economic access to alkaloid structures under
mild conditions, especially for quinolizidine and pyrrolidine-fused
azepane skeletons with yields up to 82% and good diastereoselectivity.
Subsequent oxidative cleavage conditions are developed for the synthesis
of Dendrobatid alkaloid epi-epiquinamide.