质子惰性介质中o,m,p-硝基甲苯在铂微盘电极上的电化学行为

在298K下，以铂微盘电极为工作电极，在含有0．1mol／L四丁基高氯酸铵（TBAP）为支持电解质的N，N-二甲基甲酰胺（DMF）有机溶液中分别测定了0．01mol／L邻-硝基甲苯、间-硝基甲苯和对-硝基甲苯的循环伏安曲线，讨论了扫描速度对硝基甲苯电化学行为的影响，根据实验结果推测硝基甲苯还原反应是转移电子数为1的受扩散控制的可逆过程．并对不同位甲基取代硝基甲苯的电还原行为进行了比较，结果表明在质子惰性介质中，间硝基甲苯最容易被还原，对硝基甲苯次之，而邻硝基甲苯最难被还原．

Electrochemical behavior of ortho-, meta-, and para- nitrotoluene in aprotic medium on Pt micro-disk electrode

Electrochemical reduction of ortho-,meta-, and para-nitrotoluene in aprotic medium on Pt micro-disk electrode has been investigated using cyclic voltammetry.The effect of scan rate on electrochemical characteristics of nitrotoluene was discussed.The electrochemical reduction of nitro compounds showed a reversible cathodic wave corresponding to one electron transfer,and formed the nitro radical anion,which was controlled by diffusion.Also,a comparison among ortho-,meta- and para-nitrotoluene relating the effects of different positions of methyl on nitrobenzene on the easiness of formation of radical in aprotic medium was presented.The reduction potential of the nitrotoluenes was: m-nitrotoluene> p-nitrotoluene> o-nitrotoluene,a plausible explanation for these results could be ascribed to the more electron-donating properties of the methyl group on the electron density of the nitro moiety in the ortho-position and para-position compared than the meta-position.And o-nitrotoluene appeared more negative than p-nitrotoluene,probably,this result could be explained on the basis that in the ortho position the nitro group suffers steric hindrance by the proximity of the methyl group qrovoking a little loss of coplanarity between the nitro group and the aromatic ring.