Study on Synthesis and Recognition of the Receptors of Triphenylene Anions Bearing Thiosemicarbazone Schiff Base Side Chain

Three thiosemicarbazide schiff base side chain bearing triphenylene anion receptors (R1, R2 and R3) were synthesized. Their structures were characterized by 1H-NMR and IR, and their capability of recognition of anions were studied by colorimetry, UV-Vis absorption spectrometry and fluorospectrometry. As shown by the experimental results, all of the three receptors displayed efficient recognition toward F-, and R3 also shown response to Ac- and H2PO4-. It was shown in the UV-Vis absorption spectrogram of R3, upon addition of the 3 anions, the original absorption peak at 345 nm was gradually weakened, while a new absorption peak at 455 nm appeared. The 3 anion receptors were combined with the anion F- through hydrogen bond in the thiourea group of the receptors, while the anion F- behaved to have strong electronegativity, thus efficient recognition of F- by the 3 receptors was attained.