Stereoselective Ring‐Opening of gem‐Difluorocyclopropanes: An Entry to Stereo‐defined (E,E)‐ and (E,Z)‐Conjugated Fluorodienes

: The ring-opening of gem-difluorocyclopropyl acetaldehydes producing selectively (E,E)- and (E,Z)-conjugated fluorodienals is described. Two stereo-divergent methods are presented to access both stereoisomers from a common precursor, in high yield and selectivity. The mechanistic aspect of these transformations is discussed.