Diarylamine/diarylnitroxide cycle: quantum chemical and electrochemical estimation

Oleg A Levitskiy; Vyacheslav V Sentyurin; Tatiana V Magdesieva

doi:10.1016/j.heliyon.2019.e02735

Diarylamine/diarylnitroxide cycle: quantum chemical and electrochemical estimation

Heliyon. 2019 Nov 1;5(10):e02735. doi: 10.1016/j.heliyon.2019.e02735. eCollection 2019 Oct.

Authors

Oleg A Levitskiy¹, Vyacheslav V Sentyurin¹, Tatiana V Magdesieva¹

Affiliation

¹ Lomonosov Moscow State University, Chemistry Dept., Leninskie Gory 1/3, Moscow, 119991, Russia.

Abstract

Possibility for diarylamine/diarylnitroxide cycling via electrochemical N-O bond formation/bond breaking processes was considered using quantum-chemical and electrochemical methods. It was shown that electrochemically reduced diarylnitroxides undergo fast N-O bond cleavage in the presence of oxophilic Li ions. The possible reaction scheme was suggested. In contrast, in the presence of Na+ salts, aminoxyl anions are stable and can be considered as possible anodic redox active material in energy storage systems utilizing Na+ ions migration. Direct oxygenation of diarylaminyl radicals with dioxygen yielding diarylnitroxide is not feasible; multiple competing routes involving the aromatic moiety are observed instead. The results obtained shed light on possibilities and limitations for functioning of nitroxide-based redox active electrode materials.

Keywords: Diaryl nitroxides; Electrochemical bond cleavage; Electrochemistry; Electrode reactions; Organic chemistry; Redox materials; Specific solvation; Theoretical chemistry.