Pharmaceutical Chemistry Section, Van Yuzuncu Yil University, 65080, Van, Turkey.
SAFF Chemical Reagent R&D Laboratory, VAN-TEKNOKENT, Campus, 65080, Van, Turkey.
J Fluoresc. 2021 May;31(3):861-872. doi: 10.1007/s10895-021-02716-1. Epub 2021 Mar 26.
C-2 and C-5 substituted imidazole skeleton was synthesized through a one-pot two-step strategy. Synthesized molecule emits the light on ESIPT (excited-state intramolecular proton transfer). This molecule was utilized for its proton donor ability, and we have observed that fluoride and cyanide ions can be detected selectively. Different cations and anions were selected to observe the response of the synthesized molecule. However, there were not any fluorometric and colorimetric response except for fluoride and cyanide ions. Detection limits of fluoride and cyanide ions were found to be 9.22 μM and 11.48 μM, respectively. H-NMR spectra for the solution of the sensor and TBAF (tetrabuthylammoniumfluoride) were used for the identification of [L][HF] species. 3 equiv. TBAF saturated the solution of the sensor in d-DMSO, and some of the proton resonances shifted to upfield due to the through-bond effect. The disappearance of NH proton with 0.5 equiv. TBAF or TBACN (tetrabuthylammoniumcyanide) showed that there was a proton abstraction by fluoride and cyanide ions, instead of the hydrogen bond. Solid-state application was utilized, and paper test strips were applied. Emission differences emerged when the sensor loaded strips were reacted with TBAF. Time resolved experiments revealed that solution of the sensor and TBAF in DMSO have multiexponential decay, and one of the lifetime was measured as 13.4 ns.
C-2 和 C-5 取代的咪唑骨架通过一锅两步法合成。合成的分子在 ESIPT（激发态分子内质子转移）下发光。该分子被用于其供质子能力，我们观察到可以选择性地检测氟离子和氰离子。选择了不同的阳离子和阴离子来观察合成分子的响应。然而，除了氟离子和氰离子外，没有任何荧光和比色响应。氟离子和氰离子的检测限分别为 9.22 μM 和 11.48 μM。传感器溶液和 TBAF（四丁基氟化铵）的 H-NMR 谱用于识别 [L][HF] 物种。3 当量的 TBAF 使传感器在 d-DMSO 中的溶液饱和，由于键间效应，一些质子共振移向高场。与 0.5 当量的 TBAF 或 TBACN（四丁基氰化铵）反应时，NH 质子消失表明氟离子和氰离子通过质子抽提而不是氢键发生作用。还进行了固态应用，应用了纸条测试。当传感器负载的纸条与 TBAF 反应时，出现了发射差异。时间分辨实验表明，DMSO 中传感器和 TBAF 的溶液具有多指数衰减，其中一个寿命测量为 13.4 ns。
