We report experimental and computational evidence for nitrogen–fluorine halogen bonding in Ag(I)-initiated radical C–H fluorinations. Simple pyridines form [N–F–N]+ halogen bonds with Selectfluor to facilitate single-electron reduction by catalytic Ag(I). Pyridine electronics affect the extent of halogen bonding, leading to notable differences in selectivity between mono- and bis-fluorinated products. Electronic structure calculations show that halogen bonding to various pyridines alters the single-electron reduction potential of Selectfluor, which is consistent with experimental electrochemical analysis. Multinuclear correlation NMR also provides spectroscopic evidence for pyridine halogen bonding to Selectfluor under ambient conditions.
Baxter Experimental SI ChemRxiv
Baxter Theory SI ChemRxiv