Comparing the Relative Reactivities of Structurally Varied Alcohols toward Electrochemically Generated Superoxide

Abstract

is a free-radical anion of the reactive oxygen species (ROS) family. In the present study, the relative reactivities of 14 structurally varied aliphatic alcohols toward electrochemically generated O 2 * À were investigated in solutions of N,Ndimethylformamide by using cyclic voltammetry (CV). Upon the stepwise addition of each substrate, the chemical reversibility of the one-electron voltammetric reduction of the dioxygen (O 2 ) to O 2 * À was found to decrease, which enabled the extent of radical inhibition to be determined by measuring the resultant oxidative peak current (I pa ) magnitudes on the reverse scan of the CV. Based on the electrochemical responses gathered, best fit plots of the percentage decrease in the anodic peak current (%DI pa ) against the concentration of substrate added were obtained and compared according to the different classes of alcohols that were examined (linear, fluorinated, branched, and poly-hydroxylated). In addition, different parameters, such as electronic effects, steric effects, degree of hydroxylation, and kinetic effects that affect the O 2 * À scavenging abilities of the alcohols, are also discussed.