Synthesis and Fluorescence Sensing Properties of Calix[4]arenes Containing Fluorophores

Abstract

New fluoroionophores 4 and 5 derived from calix[4]arene triester monoacid chloride with 2-amino-4-(1,3-benzothiazol-2-yl)phenol and 4-aminoquinaldine, respectively, have been synthesized. A preliminary test showed that the fluorescence intensity of 5 was very low, so only 4 was subjected to cation recognition investigation. In methanol, the fluorescence intensity of 4 was quenched by Na 1 . The fluorescence intensity decreased linearly with increasing Na 1 concentration with a stability constant of log K 5 2.91 6 0.08. No significant response was observed for other alkali metal ions under the same experimental conditions.

Coordination chemistry of calix[4]arene derivatives with lower rim functionalisation and their applications

“…Disorders in the metabolism of either ion, leading to disrupted homeostasis within the body, can severely affect the overall wellbring of the individual. A number of calixarene derivatives have found application as sensors for these ions including those reported by Tuntulani and co-workers [237] (Fig. 128).…”

Modeling K+ and Ag+ Complexation by Thiacalix[4]arene Amides Using DFT: The Role of Intramolecular Hydrogen Bonding

“…The hydrogen bonds in the binding sites of the ligands, after complex formation with the metal ions, in most cases cease, as was observed experimentally for some amide derivatives of calix[4]arene. , …”

“…The hydrogen bonds in the binding sites of the ligands, after complex formation with the metal ions, in most cases cease, as was observed experimentally for some amide derivatives of calix [4]arene. 43,48 The energetic properties of all the complexes computed at the DFT PBE/L11 level are summarized in Table 2. Complexation energies, ∆E complex , are defined as the total energy of complex (E ML ) minus the sum of total energies of the most energetically favorable ligand of the corresponding configuration (E L ) and the metal ion (E M ).…”

2-Arylbenzothiazole as a Privileged Scaffold in Drug Discovery

“…Similarly the synthesis of substituted 2-arylbenzothiazoles was reported via the condensation of 2-aminothiophenol with substituted benzaldehydes in hot dimethylsulfoxide (DMSO) [4,18,[29][30][31][32][33], nitrobenzene [34] or ethanol [35,36] without the need for further oxidant. Methods for the formation of 2-arylbenzothiazoles catalysed by acids such as p-toluenesulfonic acid [37,38], trimethylsilane [39], acetic acid [40,41] or promoted by bases such as pyridine [42] or silica gel supported sodium hydrogen sulfate [43] in the absence of further oxidant (air oxidation) have also been reported. In certain cases oxidation is not spontaneous and assistance by an external oxidant is required.…”