The First α-Fluoroallenylphosphonate, the Synthesis of Conjugated Fluoroenynes, and the Stereoselective Synthesis of Vinylfluorophosphonates Using a New Multifunctional Fluorine-Containing Building Block Antonio J. Zapata Yonghong Gu Gerald B. Hammond 10.1021/jo991620p.s001 https://acs.figshare.com/articles/journal_contribution/The_First_-Fluoroallenylphosphonate_the_Synthesis_of_Conjugated_Fluoroenynes_and_the_Stereoselective_Synthesis_of_Vinylfluorophosphonates_Using_a_New_Multifunctional_Fluorine-Containing_Building_Block/3720297 Limitations on current methodologies for the introduction of CF<sub>2</sub> and CFH in complex α-fluorophosphonates led to the synthesis of a fluorine-containing building block TIPS-C⋮CCFXP(O)(OEt)<sub>2</sub>, where X = H or F. This multifunctional fluorine synthon reacts with carbonyl compounds under WHE conditions to give high yields of fluorinated conjugated enynes and enediyne. When X = F, trapping of the desilylated anion with an electrophile after TIPS removal provided exclusive access to γ-substituted derivatives of α-fluorophosphonates. When X = H, TBAF deprotection of the silyl group yields H<sub>2</sub>CCCFP(O)(OEt)<sub>2</sub> through an allenyl−propargyl resonance stabilized anion. The allene moiety has been used as template in the stereoselective synthesis of α-fluoro-β,γ-diiodopropenyl phosphonate, via electrophilic iodination, and α-fluoro-γ-amino-α,β-unsaturated phosphonates, including unsaturated phosphononucleosides, by nucleophilic displacement of an allylic iodide. Hydroamination of H<sub>2</sub>CCCFP(O)(OEt)<sub>2</sub> using secondary amines produced (Z)-α-fluoroenaminophosphonates, whereas Diels−Alder cycloaddition with cyclopentadiene provides the corresponding exocyclic vinylfluorophosphonate. 1999-12-17 00:00:00 allenyl derivative Conjugated Fluoroenynes Hydroamination yield allene moiety electrophile allylic iodide Stereoselective Synthesis New phosphononucleoside access template First TBAF deprotection Fluoroallenylphosphonate resonance Multifunctional TIPS removal exocyclic vinylfluorophosphonate Vinylfluorophosphonate introduction Diel nucleophilic displacement enediyne Limitation amines desilylated anion WHE conditions stereoselective synthesis cyclopentadiene methodology cycloaddition multifunctional fluorine synthon CF 2 carbonyl compounds electrophilic iodination CFH