ナフトキノン誘導体の有機試薬への利用研究 (第2報)

3-Aminolawsoneと金属イオンとの沈殿・呈色反応

抄録

Examinations were made on the precipitation and color reactions of 2-hydroxy-3-amino-1, 4-naphthoquinone (3-aminolawsone) and metal ions, and their limit of identification was determined. Of the 26 Kinds of common metal ions, the naphthoquinone reacted with Bi^III and Hg^II at pH 3.2 and with Bi^III, Hg^II, Cu^II, Zn^II, Fe^III, and Al^III at pH 6.8 to produce bathochromic violet to blue precipitate or color. The reaction with Bi^III, Cu^II, and Fe^III in neutral solution was comparatively sensitive. The pH at which these metal ions begin to form precipitate or coloration with the naphthoquinone and pH at which the reaction completes were measured. The pH at which the reaction begins was 0.2 with Bi^III, 2.7-2.9 with Hg^II, 3.2-3.3 with Cu^II, 4.7 with Fe^III, 4.8-4.9 with Al^III, and 6.1-6.2 with Zn^II. These facts reveal that selective detection of Hg^II and Cu^II, or specific detection of Bi^III would be possible by adjustment of pH of the reaction mixture.