1-偶氮苯-3-(3-硝基-5-氯-2-吡啶)-三氮烯的合成及其与铜的显色反应

Synthesis of the New Reagent 1-Azobenzene-3-(3-Nitro-5-Chloro-2-Pyridyl)-Triazene and Its Color Reaction with Copper

合成了新显色剂1-偶氮苯-3-(3-硝基-5-氯-2-吡啶)-三氮烯(ABNCPDT)。研究了它与铜的显色反应。在pH10.5的Na2B4O7-NaOH缓冲溶液中,Triton X-100表面活性剂存在下,试剂与铜生成4∶1型红色配合物。配合物的最大吸收峰位于540nm,表观摩尔吸光系数为1.48×105L·mol-1·cm-1。Cu2+浓度在0—480μg/L范围内符合比耳定律,用于测定铝合金中微量铜,结果满意。

The 1-azobenzene-3-（3-nitro-5-chloro-2-pyridyl）-triazene （ABNCPDT） as a chromogenic reagent was synthesized and its color reaction with copper has been investigated. In the presence of the surface active agent triton X-100 and in the Na2B4O7-NaOH medium of pH 10.5 ,ABNCPDT forms a red complex with Cu（ Ⅱ ）. The apparent molar absorbtivity of the complex is 1.48×10^5L·mol^-1·cm^-1 at an maxmium warelength of 540nm. The molar ratio of Cu（ Ⅱ ） to ABNCPDT is 1 ： 4. Beer＇s law is well obeyed in the range of 0-480μg/L for copper. The method has been applied to the direct determination of copper in aluminium alloys with satisfactory results.