A pyrene-functionalized triazole-linked hexahomotrioxacalix[3]arene as a fluorescent chemosensor for Zn2+ ions

Abstract

A new pyrenyl appended hexahomotrioxacalix[3]arene L featuring 1,2,3-triazole linkers was synthesized as a fluorescent chemosensor for Zn 2+ in mixed aqueous media. It exhibited high affinity toward Zn 2+ , and the monomer and excimer emission of the pyrene moieties could be adjusted. The binding stoichiometry of the L•Zn 2+ complex was determined to be 1:1, and the association constant (Ka) was found to be 7.05 × 10 4 M −1 . The binding behaviour with Zn 2+ has been confirmed by 1 H NMR spectroscopic analysis.

A Hexahomotrioxacalix[3]arene-Based Ditopic Receptor for Alkylammonium Ions Controlled by Ag+ Ions

“…In agreement with its C 3 -symmetric cone -in conformation, receptor cone - 1 displays the following characteristic 1 H and 13 C-NMR spectroscopic features: (1) the cone - 1 conformation is firmly established by the presence of the bridging methylene protons that have a Δδ separation between H ax and H eq of Δδ 0.41 ppm in the 1 H-NMR spectrum (CDCl 3 ). In the calix[4]arenes, the Δδ values of the ArCH 2 Ar methylene protons have been correlated with the orientation of the adjacent aromatic rings [ 33 , 34 ] and similar findings were previously observed with hexahomotrioxacalix[3]arenes [ 12 , 13 ]. (2) The 13 C-NMR spectrum of receptor cone - 1 in CDCl 3 exhibited two peaks at δ 31 and 34 ppm for the tert -butyl carbons and a single peak at δ 69 ppm for the -O C H 2 - bridge linker carbons [ 35 ].…”

“…For example, calix[4]arene derivatives incorporating crown ethers, amides, esters, and carboxylic acid groups have been shown to selectively extract metal ions [ 10 ]. Hexahomotrioxacalix[3]arenes, which are structurally related to both calixarenes and to crown ethers, have a three dimensional cavity with a potentially C 3 -symmetric structure, and have been shown to be useful ligands for metal cations [ 11 , 12 , 13 , 14 ], ammonium cations [ 15 , 16 ], and fullerene derivatives [ 17 , 18 ].…”

Luminescent Conductive Columnar π-Gelators for Fe(II) Sensing and Bio-Imaging Applications

“…It was observed that the C–H peak corresponding to the triazole moiety of 1.3 at 7.68 ppm was gradually shifted to downfield upon addition of increasing the amount of Fe 2+ ion. This implies that the Fe 2+ ion binds with the triazole moiety of 1.3 , which is in good agreement with the previous reports. , Further, binding stoichiometry of 1.3 with Fe 2+ was evaluated by Job’s plot (Figure S20) exhibiting maxima at 0.5 mol fraction, which confirmed 1:1 complexation (Figure d) . To check the possibility of aerial oxidation of iron (Fe 2+ to Fe 3+ ), titration of 1.3 with addition of increasing amount Fe 3+ was performed via fluorescence spectrometry and 1 H NMR spectroscopy.…”

Phenothiazine–rhodamine‐based colorimetric and fluorogenic ‘turn‐on' sensor for Zn2+ and bioimaging studies in live cells

“…A fluorescent, colorimetric sensor based on 8‐aminoquinoline for Zn 2+ detection in living cells through internal charge transfer (ICT) and chelation‐enhanced fluorescence mechanisms has been described previously . A pyrenyl appended hexahomotrioxacalix[3]arene was found to exhibit high selectivity towards Zn 2+ in mixed aqueous medium and using two simple compounds based on conjugated Schiff bases from indole‐derived p ‐phenylenediamine for Zn 2+ ions …”