1,2,3-三羧甲氧基苯的催化合成及其与钍的显色反应

The Catalytic Synthesis and Colour Reaction with Thorium of 1,2,3-tri(carboxylmethoxyl)benzene.

以三丁基乙基硫酸乙酯铵为相转移催化剂 ,用焦性没食子酸、一氯乙酸和氢氧化钠为原料 ,合成了一种新的钍分析试剂——— 1,2 ,3-三羧甲氧基苯 (TCMOB)。显色试验表明 ,TCMOB是一种性能优良的钍显色剂 ,在 2 5ml 4mol/L的HClO4 介质中形成 1∶1的配合物 ,其最大吸收峰位于 32 5nm ,吸光系数为ε4 2 5nm =8.86× 10 4 L·mol- 1·cm- 1,钍的含量在 0～30 μg/ 2

A new reagent, 1,2,3 tri(carboxylmethoxyl) benzene(TCMOB), which is highly sensitive and selective chromogenic to the determination of thorium, was catalytically synthesized from pyrogallol, chloroacetic acid and sodium hydroxide in a chloroform solvent. In a 2.5ml 4mol/L perchloric acid medium, thorium reacts with TCMOB to form a stable 1∶1 chelate, which has a maximum absorption at 325nm. Beer's law is obeyed over the range of 0～30μg/25ml, whereas the apparent molar absorptivity is 8.86×10 4L·mol -1 ·cm -1 .