Approaches to the assembly of the antifungal agent FR-900848: determination of the geometry of the dicyclopropylethene unit and an X-ray crystallographic study of (1R,2S)-1,2-bis[(1S,2S)-2-methylcyclopropyl]-1,2-ethanediyl 3,5-dinitrobenzoate
Abstract
Whitham elimination is used to prepare (Z)-1,2-bis[(1S,2S)-2-methylcyclopropyl]ethene, which along with the corresponding E-alkene, is used as a structural model to determine that the geometry of the dicyclopropylethene unit of FR-900848 is trans.