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>Polarographic and electrochemical studies of some aromatic and heterocyclic nitro compounds: Part V. Polarographic reduction of cyano‐and carboxamido‐nitropyrazoles
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Polarographic and electrochemical studies of some aromatic and heterocyclic nitro compounds: Part V. Polarographic reduction of cyano‐and carboxamido‐nitropyrazoles
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机译：Polarographic and electrochemical studies of some aromatic and heterocyclic nitro compounds: Part V. Polarographic reduction of cyano‐and carboxamido‐nitropyrazoles
AbstractReduction of the nitro group in 1‐alkyl‐4‐cyano‐5‐nitropyrazoles follows a pattern similar to that of 1‐alkyl‐5‐nitropyrazoles, involving the sequence H+, e, H+, e, 2e, 2H+. On the other hand, the sequence of proton and electron transfers in the reduction of the nitro group in 1‐alkyl‐3‐nitro‐4‐cyanopyrazoles differs from that in 1‐alkyl‐3‐nitropyrazoles. Similarly, the reductions of 4‐cyano‐3(5) ‐nitropyrazole differs from that of 3(5)‐nitropyrazole, even when both of these reductions are affected by the dissociation of the NH group with pKB= 6.26 and 9.81, respectively. Similarly, the behavior of 1‐alkyl‐4‐carboxamido‐5‐nitropyrazoles resembles that of 1‐alkyl‐5‐nitropyrazoles, but that of 1‐alkyl‐3‐nitro‐4‐carboxamidopyrazoles is different from that of 1‐alkyl‐3‐nitropyrazoles. In 1‐alkyl‐4‐carboxamido‐5‐hydroxylaminopyrazoles, the carboxamido group is reduced in a two‐ and four‐electron process, but the low absolute value
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