Güngör Özlem, Nuralin Levent
Department of Chemistry, Faculty of Science, Gazi University, 06500, Ankara, Turkey.
Department of Chemical Engineering, Faculty of Engineering, Gazi University, 06570, Ankara, Turkey.
J Fluoresc. 2024 May;34(3):1319-1342. doi: 10.1007/s10895-023-03368-z. Epub 2023 Aug 2.
A naphthylidene-diimine L was newly designed, and its structure was identified by elemental analysis and spectroscopic methods. The effect of temperature, acid-base and light on enol-keto tautomerism in this Schiff base was evaluated by colorimetry, UV-Vis and fluorescence spectroscopy. Under irradiation 365 nm, L emitted yellow, orange and strong green emission in pure, basic and aqueous DMSO media (v/v, 1/1), respectively. Its ionochromic behavior against various cations (Fe, Al, Cr, Cu, Co, Ni, Zn, Cd, Pb, Ba and Ag) and anions (F, Cl, CHCOO, SO, SO, HSO, HPO, NO, CN, and OH) was investigated in aqueous DMSO media (v/v, 1/1) by UV-Vis and fluorescence experiments. Dark yellow color of L changed to colorless for Fe, Cr and HSO ions, and turned to light yellow for Al and Cu ions, and to orange for CN and OH ions. According to UV-Vis data, the chemosensor displayed selective recognition towards Fe, Al, Cu, HSO, CN and OH with a 1:1 stoichiometric ratio. At the excitation wavelength of 365 nm, L gave strong yellowish white emission (λ = 445 and 539 nm) in the presence of Al, and the intensity increased about 12.5 times. On the other hand, the chemosensor displayed one emission band at 452 nm and 450 nm in the presence of CN and OH with 1.9 fold and 2.3 fold fluorescence enhancement, respectively.
新设计了一种萘亚基二亚胺L，并通过元素分析和光谱方法确定了其结构。采用比色法、紫外-可见光谱法和荧光光谱法评估了温度、酸碱和光照对该席夫碱中烯醇-酮互变异构的影响。在365nm光照下，L在纯、碱性和水-DMSO介质（v/v，1/1）中分别发出黄色、橙色和强绿色荧光。通过紫外-可见光谱和荧光实验研究了其在水-DMSO介质（v/v，1/1）中对各种阳离子（Fe、Al、Cr、Cu、Co、Ni、Zn、Cd、Pb、Ba和Ag）和阴离子（F、Cl、CHCOO、SO、SO、HSO、HPO、NO、CN和OH）的离子变色行为。L的深黄色在Fe、Cr和HSO离子作用下变为无色，在Al和Cu离子作用下变为浅黄色，在CN和OH离子作用下变为橙色。根据紫外-可见光谱数据，该化学传感器对Fe、Al、Cu、HSO、CN和OH具有选择性识别，化学计量比为1:1。在365nm激发波长下，L在Al存在下发出强烈的黄白色荧光（λ = 445和539nm），强度增加约12.5倍。另一方面，该化学传感器在CN和OH存在下分别在452nm和450nm处显示一个发射带，荧光增强分别为1.9倍和2.3倍。
