新不对称偶氮羧衍生物的合成及其与钙离子的β型显色反应  

The Synthesis of New Unsymmetric Derivatives of Carboxylazo and Their β-type Colour Reactions with Calcium Ion

作　　者：杜迎翔[1] 罗国安[1] 陈玉英[1] 李勇[1] 潘教麦[2] 徐钟隽[2] 

机构地区：[1]中国药科大学分析化学教研室,南京210009 [2]华东师范大学化学系,上海200062

出　　处：《化学学报》1991年第12期1497-1502,共6页Acta Chimica Sinica

摘　　要：我们合成了五种新的不对称偶氮羧衍生物,并研究了它们与钙离子之间的一种特殊反应—β型反应,考察了试剂分子结构与反应性能的关系.着重探讨了对羧基偶氮羧与钙离子的β型反应行为,在柠檬酸介质中,钙离子与该试剂形成组成比为1:2的灵敏的稳定配合物,最大吸收波长为718nm(△λ=157nm),表观摩尔吸光系数ε=1.51×10~5L·mol^(-1)·cm^(-1),测定条件下,1—13μgCa/25mL 符合 Beer 定律,采用小体积显色,反应可在15分钟内进行完全,配合物可稳定4小时不变.动力学研究结果表明,对羧基偶氮羧与钙离子只发生β型反应,反应级数为2.Five new unsymmetric derivatives of carboxylazo,p-carboxycarboxylazo,p-chlorocarboxylazo,p-methylcarboxylazo,p-sulfocarboxylazo and m-nitrocarboxy-lazo-were synthesized.A new type,β-type reactions of calcium ion with these reagents werestudied.The relationship between the mol(?)cular structure of reagents and reaction condi-tions was detected.The β-type reaction behavior between calcium ion and p-carboxycar-boxylazo was investigated in detail,calcium ion reacts with it to form a 1:2 sensitive andstable β-type complex in citric acid medium,having an absorption maximum at 718 nm(⊿λ=157nm).Beer′s law is obeyed for 1—13μg of calcium in 25mL of solution withan apparent molar absorptivity of 1.51×10~5L·mol^(-1)·cm^(-1) at 718nm.The complexformation is complete within 15 min in a small volume and the resulting complex isstable for 4h after dilution.Kinetic study on this system has shown that calcium ionreacts with p-carboxycarboxylazo to form only a β-type complex and the order ofreaction is 2.

关 键 词：钙离子 不对称偶氮羧 β-显色反应 

分 类 号：O614.231[理学—无机化学]