2—(4—安替比啉偶氮)—5—二甲氨基苯胺合成及其与钴(Ⅱ)显色反应的研究

Synthesis of 2-(4-Antipyrinylazo)-5-dimethylamino aniline and it's Chromogenic reation with Co(Ⅱ)

合成了新的安替比啉偶氮试剂2-(4-安替比啉偶氮)-5-二甲氨基笨胺(AADMAA)。在pH4时,AADMAA与Co(Ⅱ)形成红色络合物,λ_(max)为520nm,ε为6.48×10~4。钴量在0—20μg/25mL符合比尔定律,选择性较好,加入适当的掩蔽剂可以不经分离直接测定某些物料中微量钴。

A new agent, 2-(4-antipyrinylazo)-5-dimethyl aminoaniline (AADMAA), was prepared. Co(Ⅱ) was determined spectrophotometrically by complex formation with AADMAA at pH 4. The maximum absorption is at 520 nm. The molar absorptivity was 6.48×10~41.mol.cm. Beer's law is obeyed in the range of 1 to 20 ng Co(Ⅱ)/ 25 mL. The method has been used to determine trace Co(Ⅱ) in some materials without separation and satisfactory results were obtained.