Terpyridine-Functionalized Calixarenes: Synthesis, Characterization and Anion Sensing Applications

Abstract

Lanthanide complexes have been developed and are reported herein. These complexes were derived from a terpyridine-functionalized calix[4]arene ligand, chelated with Tb3+ and Eu3+. Synthesis of these complexes was achieved in two steps from a calix[4]arene derivative: (1) amide coupling of a calix[4]arene bearing carboxylic acid functionalities and (2) metallation with a lanthanide triflate salt. The ligand and its complexes were characterized by NMR (1H and 13C), fluorescence and UV-vis spectroscopy as well as MS. The photophysical properties of these complexes were studied; high molar absorptivity values, modest quantum yields and luminescence lifetimes on the ms timescale were obtained. Anion binding results in a change in the photophysical properties of the complexes. The anion sensing ability of the Tb(III) complex was evaluated via visual detection, UV-vis and fluorescence studies. The sensor was found to be responsive towards a variety of anions, and large binding constants were obtained for the coordination of anions to the sensor.

Complexing Eu3+/Tb3+ in a Nanoscale Postmodified Zr-MOF toward Temperature-Modulated Multispectrum Chromism

“…The first step toward the postsynthetic modification of Zr-NMOF to the proposed luminescent MOF was carried out by grafting presynthesized 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine (ctpy) (Figure S5) onto the framework through a solvent-assisted linker exchange to provide a binding center for the Ln 3+ (see the Experimental Section). , It is well known that terpyridine-based ligands are excellent chelating motifs for Ln 3+ to induce an antenna effect. , Moreover, the triplet state level of the ctpy ligand was found to be 25,123 cm –1 as obtained from the density functional theory (DFT) calculation and was suitable to sensitize both Tb 3+ and Eu 3+ (Figure S6). ,, The successful incorporation of ctpy into Zr-NMOF was confirmed by 1 H NMR spectroscopy of the postsynthetically modified MOF, which was labeled as Zr-ctpy-NMOF (Figure S7).…”

“…25,34 It is well known that terpyridine-based ligands are excellent chelating motifs for Ln 3+ to induce an antenna effect. 35,36 Moreover, the triplet state level of the ctpy ligand was found to be 25,123 cm −1 as obtained from the density functional theory (DFT) calculation and was suitable to sensitize both Tb 3+ and Eu 3+ (Figure S6). 13,37,38 The successful incorporation of ctpy into Zr-NMOF was confirmed by 1 H NMR spectroscopy of the postsynthetically modified MOF, which was labeled as Zrctpy-NMOF (Figure S7).…”

Synthesis, Structure and Magnetic Properties of Some Copper(II) Complexes Supported by Pendant Calix[4]arene Ligands

“…[2,3] Thus, the photophysical properties of several calix [4]arenes bearing two pyrene, [4] anthracene, [5] naphthalene, [6] and dipyrenyl [7,8] groups have been exploited as fluorescence sensors for the selective recognition of various guest molecules. [9][10][11][12] Typically, such calix [4]arenes bind the guest molecules by π-π stacking and cation-π interactions in a pincer-like mode. [13][14][15][16] Another set of calix [4]arenes comprises pendant ligand arms in order to bind transition metal and lanthanide ions and to control the structure and functions of the resulting complexes.…”

Design strategies and applications of novel functionalized phenazine derivatives: a review

“…[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] In the design of photoelectric functional materials, it becomes one of the most attractive and appropriate structures. [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40] Typically, the functionalization of nitrogen atoms on the phenazine skeleton leads to the formation of a series of phenazine derivatives with variable absorption and fluorescence properties. From then on, researchers have functionalized phenazine in a variety of ways, including alkyl, thiophene, aryl, cyanide and metal bridging, resulting in obvious colored, excellent conductive functional materials with photophysical properties that differ dramatically from those of other unmodified materials.…”