M. Zanoni, N. Stradiotto
Aug 26, 1991
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0
Influential Citations
8
Citations
Journal
Journal of Electroanalytical Chemistry
Abstract
Abstract The reduction of benzenesulfonyl derivatives of n-butylamine and N,N -di-n-butylamine with nitro substituents at the 2, 3 and 4 positions of the phenyl ring in N,N -dimethylformamide is reported. The N , N -di-n-butyl-4- and N -n-butyl-2-nitrobenzenesulfonamides are reduced in two cathodic steps. The first one, at about −0.90 V vs. SCE, a reversible one-electron process, gives a stable anion radical. The second reduction step at −1.70 V vs. SCE leads to cleavage of the S-N bond in good yields ( > 70%). It is shown that the reduction of the N -n-butyl-3- and N -n-butyl-4-nitrobenzenesulfonamide is different, with three reduction steps. The first reduction step occurs with the formation of an unstable anion radical, which decomposes via N-H bond cleavage. The reduction of this sulfonamide anion occurs at −1.16 V vs. SCE and the third cathodic step arises at −1.70 V vs. SCE when the remaining radical anion is reduced to its dianion. The S-N bond cleavage is rapid but is always a minor process. The mechanisms of the reduction are discussed.