| Abstrakt: |
Some aspects of the chemical degradation of N-(3, 4-dimethyl-5-isoxazolyl)-4-amino-1, 2-naphthoquinone were investigated as a function of pH and temperature. In acid and neutral pH, four main degradation products were identified: 2-hydroxy-1, 4-naphthoquinone, 2-butanone, ammonia, and hydroxylamine. No significant buffer effects were observed for the buffer species used in this study. The pH–rate profile exhibited a specific acid catalysis which is important at pH values <3.5, and an inflection point at pH 1.10 corresponding to a pKavalue. From Arrhenius plots, the activation energy was found to be 17.8 ± 0.3 kcal/mol. |
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