[Br:1][C:2]1[N:7]=[C:6]([C:8](=[O:10])[CH3:9])[CH:5]=[CH:4][CH:3]=1.[F:11][B-](F)(F)F.F[B-](F)(F)F.F[N+]12CC[N+](O)(CC1)CC2>CO>[Br:1][C:2]1[N:7]=[C:6]([C:8](=[O:10])[CH2:9][F:11])[CH:5]=[CH:4][CH:3]=11-(6-Bromopyridin-2-yl)ethanone (2 g, 10.0 mmol) and 1-fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (9.65 g, 15.0 mmol) were combined in MeOH (100 mL) and heated to reflux for 3 days. After cooling to room temperature, the white solid (alumina) was removed by filtration and filtrate was concentrated in vacuo. The residue was taken up in EtOAc and water and extracted with EtOAc (2×). The combined organic extracts were washed with brine, dried over MgSO4, filtered, and concentrated in vacuo. The residue was stirred in a combination of 6 N HCl and Et2O overnight. The organic phase was separated and the aqueous phase extracted with Et2O. The combined organic extracts were washed with brine, dried over MgSO4, filtered, and concentrated in vacuo. Purification of the residue by silica gel column chromatography (0-20% EtOAc-hexanes) gave the title compound as a white solid.
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