Abstract
The electrochemical behaviors of N-(2-benzylbenzoxazol-5-yl)benzamide (B1), N-(2-benzylbenzoxazol-5-yl)- 4-nitrobenzamide (B2) and N-(2-(4-chlorobenzyl)benzoxazol-5-yl)-4-nitrobenzamide (B3) were investigated by cyclic voltammetry (CV), square wave voltammetry (SWV), differential puls voltammetry (DPV), chronoamperometry (CA) and bulk electrolysis (BE) techniques in dimethylsulfoxide (DMSO) containing 0.1 M tetrabutylammonium tetrafluoroborate (TBATFB). The number of electrons transferred and diffusion coefficients were calculated by using chronoamperometry and bulk electrolysis techniques. Standard heterogeneous rate constants for the electrochemical reduction were calculated by Klingler-Kochi technique. The data obtained showed that the quantitative determination of benzoxazoles could be done by using DPV and SWV rapidly and sensitively. For the DPV technique, linear working ranges for B2 and B3 were found to be (6.0 x 10-7-4.0 x 10-4) M and (1.0 x 10-6-2.0 x 10-4) M respectively. The corresponding ranges for these compounds found by SWV were (6.0 x 10-7-4.0 x 10-4) M and (1.0 x 10-6-2.0 x 10-4) M. The detection limits for B2 obtained from DPV and SWV were calculated to be 1.33 x 10-7 M and 1.76 x 10-7 M respectively. The detection limits with B3 deplicted to be almost the same.
Keywords: Benzoxazoles derivatives, Voltammetry, Differential-pulse voltammetry, Square-wave voltammetry
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