The TEMPO-BF₃ complex is a plausible candidate for the non-electroactive species formed through the interaction with BF₃-CH3CN, as similar adducts have been isolated and identified in reactions between TEMPO and Lewis acids, as shown in several previous studies . However, since our initial attempts to isolate or confirm the TEMPO-BF₃ complex have not been conclusive, we refer to this nonredox species as TEMPO-X for the time being.