Synthesis of cis,cis,cis,cis-[5.5.5.4]-1-azafenestrane with discovery of an unexpected dyotropic rearrangement

Article abstract of DOI:10.1002/anie.200500367

(Figure Presented) An unprecedented skeletal reorganization initially hindered a concise route based on a tandem [4+2]/[3+2] nitroalkene cycloaddition for the synthesis of the strained title compound. Conditions to suppress the observed dyotropic rearrangement were developed, and X-ray crystallographic analysis of the BF₃ derivative (see picture) of the azafenestrane revealed significant planarization around the central carbon atom.