Studies of the polarographic and coulometric behaviour of aromatic nitro-compounds I. Nitrobenzene in ethanol

Vijayalakshamma, SK

doi:10.1016/0368-1874(69)87011-5

Cited by 2 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, previously published work showed that in anhydrous N , N -dimethylformamide upon the addition of a proton source the polarographic reduction of nitrobenzene to a radical anion decreases in intensity and a new reduction wave occurs that is attributed to the four-step, four-electron production of N -phenylhydroxylamine . In aqueous media, the reduction of nitrobenzene proceeds directly to the formation of N -phenylhydroxylamine, which in acidic solutions undergoes an additional two-proton, two-electron transfer at more negative potential to produce aniline. ,,, Recently, a computational study investigated the electrochemical mechanism and potentials of TNT reduction in aqueous solution, making reference to the literature of experimental electrochemistry of various nitroaromatic compounds . While the authors showed that the nitro group in the 2 position of TNT is most easily reduced, it was not clear whether this is also true for DNT.…”

Section: Introductionmentioning

confidence: 65%

“…31 In aqueous media, the reduction of nitrobenzene proceeds directly to the formation of N- phenylhydroxylamine, which in acidic solutions undergoes an additional two-proton, two-electron transfer at more negative potential to produce aniline. 29,30,36,37 Recently, a computational study investigated the electrochemical mechanism and potentials of TNT reduction in aqueous solution, making reference to the literature of experimental electrochemistry of various nitroaromatic compounds. 38 While the authors showed that the nitro group in the 2 position of TNT is most easily reduced, it was not clear whether this is also true for DNT.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Electrochemical Reduction of 2,4-Dinitrotoluene in Aprotic and pH-Buffered Media

et al. 2015

View full text Add to dashboard Cite

As an intermediate in industrial 2,4,6-trinitrotoluene (TNT) production, 2,4-dinitrotoluene (DNT) is one of the most prevalent impurities in TNT. Its high volatility as compared to TNT makes DNT a telltale sign of TNT explosives, and the electroactivity of its nitro groups lends itself to electrochemical detection as a particularly promising route for DNT sensing. In this work, the electrochemical reduction mechanism of DNT was investigated by cyclic voltammetry. In anhydrous solvents and in the absence of another source of protons, DNT exhibits two well resolved one-electron transfers. The radical anion formed by reduction of DNT is shown to be sufficiently basic to deprotonate the weakly acidic methyl group of still unreacted DNT, giving rise to an intense blue color. In contrast, in the presence of a pH buffer, DNT is readily reduced in acetonitrile to 2,4-bis(N-hydroxylamino)toluene by an irreversible transfer of eight protons and eight electrons. Density functional calculations suggest that the pathway to 2,4-bis(N-hydroxylamino)toluene is thermodynamically more favorable than the formation of aminonitrotoluene. This occurs at a substantially less negative potential than in the absence of protons, which shows that the reduction of DNT in the presence of protons is directly coupled to the protonation of DNT. The enhancement in signal observed for DNT in the presence of protons indicates that the incorporation of a proton source to electrochemical sensing setups will greatly enhance the sensitivity of electroreductive DNT analysis.

show abstract