Polarographic studies of some organic compounds

Abstract

Polarographic investigations of ambrette musk, ketone musk and xylene musk have been carried out. Each of these compounds showed a clear reducing wave by using 0.25 M NaBr as a supporting electrolyte and 0.04 M Britton-Robinson buffer in 80% alcoholic solution containing 0.028% gelatin. The wave height of these compounds was proportional to the concentration within the concentration range 1.00. 1mM and pH range 2.710.6. The wave heights decreased in the order xylene musk, ambrette musk and ketone musk; and each of the half-wave potentials was shifted to the negative side with an increase in pH. The diffusion coefficient calculated from the Stokes-Einstein equation was applied in the Ilkovic equation to obtain the electron number, from which the mechanism of reduction at the dropping mercury electrode was then deduced. It was found that the quantitative determination of each of these compounds by the polarographic method was possible. The structural formula of ambrette musk was shown to be different from the heretofore accepted one with three nitro groups : it was ascertained to be a formula with two nitro groups.The Polarographic behavior of piperine has been investigated. A clear reducing wave was indicated by using 0.25 M NaBr as a supporting electrolyte and 0.04 M Britton-Robinson buffer in 80% alcoholic solution containing 0.028% gelatin. Quantitative determination by polarography was possible as the wave heights were proportional within the concentration of 1.00.1 mM and pH range of 2.610.7. The half-wave potentials were shifted toward the negative side with an increase of pH value. Shifting toward the positive side, though slight, was observed with an increase of pH value within the range of 7.010.7. The mechanism of reduction at the dropping mercury electrode was deduced by applying the diffusion coefficient calculated from the Stokes-Einstein equation for determining the electron number in the Ilkovic equation.