Selectfluor as a nucleofuge in the reactions of azabicyclo[n.2.1]alkane β-halocarbamic acid esters (n=2,3)

The ability of Selectfluor to act as a nucleofuge for hydrolysis of beta-anti-halides was investigated with N-alkoxycarbonyl derivatives of 6-anti-Y-7-anti-X-2-azabicyclo[2.2.1]heptanes and 4-anti-Y-8-anti-X-6-azabicyclo[3.2.1]octanes. The azabicycles contained X = I or Br groups in the methano bridge and Y = F, Br, Cl, or OH substituents in the larger bridge. The relative reactivities of the halides were a function of the azabicycle, the halide, and its bridge and the addition of Selectfluor or HgF(2) as a nucleofuge. All halide displacements occurred with retention of stereochemistry. Selectfluor with sodium bromide or sodium chloride, but not sodium iodide, competitively oxidized some haloalcohols to haloketones. A significant 15.6 Hz F center dot center dot center dot HO NMR coupling was observed with 4-anti-fluoro-8-anti-hydroxy-6-azabicyclo[3.2.1]octane.