Fig. 4: Scope of nucleophiles^a.

^aReaction conditions: For 66–70 and 75–80: S1 (0.3 mmol), Et₄NBF₄ (0.2 M), corresponding nitrile solvent (3 mL) or acid solvent (3 mL), HFIP (1.0 mL), MeSO₃H (0.1 mL), graphite felt (2 mm) anode, Pt cathode at rt, in an undivided cell with constant voltage (2.4 V), under air atmosphere. Isolated yield. ^bReactions performed with 3.6 mmol nucleophile (71: MsNH₂, 72: EtSO₂NH₂, 73: 2-oxazolidone, 74: urethane) in 3 mL DCM. ^c0.8 mL TFA was used. ^dGraphite felt (6.5 mm) was used as anode. ^e0.1 mmol of substrate. HFIP 1, 1, 1, 3, 3, 3-hexafluoro-2-propanol, TFA trifluoroacetic acid, DCM dichloromethane, Ac acetyl, Ms methanesulfonyl, ⁿPr n-propyl.