Synthesis and antioxidant activity of dodecyl-(3-(4-hydroxyaryl)propyl)selenides

The article presents a synthesis of structurally related series of dodecyl-(3-(4-hydroxyaryl)propyl)selenides with different number and different structure of the ortho-alkyl substituents. Corresponding 3-(4-hydroxyaryl)-1-bromopropanes, 1-chlorododecane, selenium, and sodium sulfite were used as synthons. The synthesis of the target compounds were carried out via preparation of the bis-dodecyldiselenide as intermediate. The synthesized dodecyl-(3-(4-hydroxyaryl) propyl)selenides were active in reactions with peroxide radicals and peroxides, hence it work like hybrid antioxidants. Antiradical activity of these compounds studied in the model reaction of initiated cumene oxidation at 60 °C. Experimentally measured rate constant interaction with cumylperoxyde radicals ranged from 2.6 ∙ 104 M-1 s-1 ∙ for ortho-unsubstituted dodecyl-(3-(4-hydroxyphenyl)propyl)selenide to 1.3 ∙ 105 ∙ M-1 s-1 for its 3,5-dimethylated analogue. It has been shown, that replacement of selenium in the molecules of dodecyl-(3-(4-hydroxyaryl)propyl)selenides to sulfur does not lead to significant changes in antiradical properties of the compounds. However, the study of the kinetics of decomposition of cumene hydroperoxide in acetic acid at 60 °C in the presence of dodecyl-(3-(4-hydroxyaryl)propyl)selenides and corresponding dodecyl-(3-(4-hydroxyaryl)propyl)sulfides revealed significant differences in peroxide destruction activity these classes of compounds. In conditions of the experiment sulfides were reacted with equimolar amounts of cumene hydroperoxide, while selenides exhibited higher activity and digested whole peroxide (6-fold excess).