Development of chromogenic sensors for copper and silver ions

• Main Authors: Tzu-Ling Chou, 周紫綾
• Other Authors: Yao-Pin Yen
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/94053975591690728901

碩士 === 靜宜大學 === 應用化學系 === 103 === This work describes the synthesis of two Schiff bases based on an 8-formyl-7-hydroxy-4-methylcoumarin framework, (E)-7-hydroxy-8-((2-hydroxyphenylimino)methyl)-4-methylcoumarin (9) and (E)-7-hydroxy-8-((3-hydroxynaphthalen-2-ylimino)methyl) -4-methylcoumarin (10) and were determined by 1H NMR, 13C NMR and HRMS. The Schiff bases, obtained by condensation of amines and aldehydes, can be applied in the detection of metal ions. Receptors 9 and 10 can detect Cu2+ and indicate its presence by visible color change. In addition, they undergo a photochemical reaction in the presence of Ag+ which also produces a color change. In a mixed solvent system (DMSO/H2O 3 : 7), the color of receptor 9 will change from pale yellow to golden yellow in the presence of Cu2+, while receptor 10 changes from colorless to yellow. By spectroscopic evidence including Job's plots, we have shown receptors 9 and 10 interact with Cu2+ in a 2 : 1 ratio. In a mixed solvent system (CH3OH/H2O 3 : 7) and at low concentration (2 × 10-6 M), receptors 9 and receptor 10 in the presence of Ag+ will undergo a photochemical reaction producing a visible color change from colorless to purple.