Acylthiourea derivatives as colorimetric sensors for anions: Synthesis, characterization and spectral behaviors

摘要

Several acylthioureas have been synthesized to develop colorimetric sensors for detection of biologically important anions. UV-vis titration experiments indicated that the absorbance values have a good linear relationship with concentration of anions when the anions were added in AR-1, AR-4 and AR-6 sensor molecules. The detection limit to AcO- and F- is 5 x 10(-6) mol/L when the concentration of receptors are 2 x 10(-5) mol/L. Especially, compounds AR-1 and AR-4, decorated with strong electron-withdrawing NO2 substituent, showed augmented anion sensing properties, being capable of naked-eye detecting of F- and AcO- when the water content is lower than 15%. The recognition details of anion sensing were also assessed using H-1 NMR technique and confirmed that the basic anions induced deprotonation of N-H. (C) 2015 Elsevier B.V. All rights reserved.