Clarification and Application of Selectivity for Metal Ion of Ternary System of Aldonic Acid, Boric Acid, and Metal (II) Ion

醛糖酸、硼酸、金属(II)离子三元体系金属离子选择性的澄清及应用

• 批准号: 06640779
• 负责人: AIZAWA Sen-ichi
• 金额: $ 1.41万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640779/
• 关键词: aldonic acid; potentiometry; ternary system; selectivity for metal ion; 錯形成反応; 三元系錯形; aldonic acid; potentiometry; ternary system; selectivity for metal ion; 錯形成反応; 三元系錯形

The complexation equilibria for the binary system of glucosaminic acid (2-amino-2-deoxy-D-gluconic acid) and boric acid and that of glucosaminic acid and metal (II) ion and the ternary system of glucosaminic acid, boric acid, and metal (II) ion have been investigated by potentiometric measurements using Ni (II), Zn (II), Cd (II), and Pb (II) as the metal (II) ions. The structures of the present complexes have been characterized by ^<13>C and ^<11>B NMR.The additional stabilization by forming the ternary systems is the greatest in the Cd (II) system. It is considered that the conformation of the glucosaminic acid in its boric-acid binary systems can distinguish the difference in the ion size. On the other hand, the ternary system with germanic acid instead of boric acid exhibits no selectivity for the metal (II) ions probably due to the adjustment of the geometry of the five-coordinate germanic acid. It is revealed that the Cd (II) complex is more stable than the Pb (II) complex in the ternary system with boric acid while the stability in the glucosaminic-acid binary system is reversed. The development of such a new selectivity arising from the ternary system is the major purpose for the present study. Because it is easy for the ternary complex to dissociate the metal (II) ion by raising the pH value of the solution, the present system is extensively applicable for the separation or concentration of the metal ion in the field of analytical chemistry.

The complexation equilibria for the binary system of glucosaminic acid (2-amino-2-deoxy-D-gluconic acid) and boric acid and that of glucosaminic acid and metal (II) ion and the ternary system of glucosaminic acid, boric acid, and metal (II) ion have been investigated by potentiometric measurements using Ni (II), Zn (II), Cd (II), and Pb （ii）作为金属（ii）离子。本络合物的结构以 ^<13> c和 ^<11> b nmr的特征。形成三元系统的额外稳定化是CD（II）系统中最大的。据认为，在其硼酸二元系统中，葡萄糖氨酸的构象可以区分离子大小的差异。另一方面，搭配日耳酸代替硼酸的三元系统对金属（II）离子没有选择性，这可能是由于调整了五坐标日耳曼酸的几何形状。据表明，与三元系统中的Pb（II）复合物相比，CD（II）复合物具有硼酸的Pb（II）复合物，而葡萄糖胺 - 酸性二元系统的稳定性被逆转。从三元系统产生的这种新选择性的发展是本研究的主要目的。由于三元络合物很容易通过提高溶液的pH值来解离金属（II）离子，因此本系统广泛适用于分析化学领域中金属离子的分离或浓度。