Effects of Substituents in the Aryl Moiety of Bis(1, 2diary-1, 2-ethylenedithiolato)nickel on the Quenching of Singlet Oxygen and the Reaction with Singlet Oxygen

Abstract

Bis(1, 2-diaryl-1, 2-ethylenedithiolato)nickel complexes (X-DTNi; where X represents the substituent in the aryl moiety in the ligand) are efficient quenchers for singlet oxygen.
The formation of 2, 5-dimethyl-2-hydroperoxy-5-methoxy-2, 5-dihydrofuran in the reaction. of 2, 5-dimethylfuran with ¹O₂ generated from H₂O₂ and NaC1O is suppressed more by 'X-DTNi with electron-donating X than by X-DTNi with electron-accepting X (Fig.1). Quenching of ¹O₂ by X-DTNi is not linear to the concentration of X-DTNi, and quenching is more efficient in higher concentrations of X-DTNi than in their lower concentrations. (Fig.1 and Table 2).
The durabilities of X-DTNi with electron-donating X against ¹O₂ are lower than those with electronaccentinu X (Fin.2).