Cascade fluorofunctionalisation of 2,3-unsubstituted indoles by means of electrophilic fluorination

Cascade fluorofunctionalisation of 2,3-unsubstituted indoles featuring the formation of C–C, C–F and C–O bonds via electrophilic fluorination using N-fluorobenzenesulfonimide is described. The use of an O-nucleophile tethered to the nitrogen of indoles enables the synthesis of polycyclic fluorinated indoline derivatives from simple precursors in 40–63% yields.