Pulsed electrolysis: enhancing primary benzylic C(sp 3 )-H nucleophilic fluorination.

Electrosynthesis is an efficient and powerful tool for the generation of elusive reactive intermediates. The application of alternative electrolysis waveforms provides a new level of control for dynamic redox environments. Herein, we demonstrate that pulsed electrolysis provides a favourable environment for the generation and fluorination of highly unstable primary benzylic cations from C(sp 3 )-H bonds. By introduction of a t off period, we propose this waveform modulates the electrical double layer to improve mass transport and limit over-oxidation.