Scheme 2. Synthesis of aryl triflates through ex situ generation of CF₃SO₂F gas in a two-chamber reactor. Unless stated otherwise, method A was used. Generation chamber: N-phenyltrifluoromethanesulfonimide (PhNTf₂, 1.5 equiv.), KHF₂ (1.0 equiv.) and MeCN (0.86 M, 1.75 mL) at room temperature. Reaction chamber: (hetero)aryl alcohol (1.0 mmol, 1.0 equiv.), N,N-diisopropylethylamine (DIPEA, 1.5 equiv.) in 3.0 mL of MeCN and 1.0 mL of H₂O. Reaction details see ESI Section 4.† Isolated yield after column chromatography unless stated otherwise. Between brackets is given the ¹⁹F NMR yield using PhCF₃ as internal standard, between parentheses the reaction time. [a] Isolated yield after aqueous work-up. [b] 2.5 equiv. of DIPEA were used in the reaction chamber. [c] 3 mL MeCN was used in the reaction chamber as solvent, and the crude reaction mixture was purified on silica directly without aqueous work-up. [d] 2.5 equiv. of PhNTf₂ and 1.67 equivalents of KHF₂ were used in the generation chamber. [e] The reaction was set under Argon atmosphere. [f] Et₃N (3.5 equiv.) and DMSO (0.25 M, 4.0 mL) were used in the reaction chamber. [g] The corresponding boronic acid was used as the starting material, and protected afterwards with pinacol. [h] Yield corresponds to product isolated as an HCl salt. [i] The assay yield is reported (average over two runs), defined by dividing the [M + 132] peak area by the total AUC of the HPLC-MS TIC chromatogram.