Abstract The kinetics of reactions of hindered phenols (2, 4, 6-trimethylphenol, 2, 6-di-tert- butyl-4-methylphenol and 2, 4, 6-tri-tert-butylphenol) with 1-fluoro-4-chloromethyl-1, 4- diazoniabicyclo [2.2. 2] octane bis (tetrafluoroborate)(Selectfluor™, F-TEDA-BF 4) in acetonitrile in the absence or presence of various sources of external nucleophile (alcohols, water, trifluoroacetic acid) were studied. The reactions exhibited overall second-order ...