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A new chromogenic fluoride sensor based on 1,3-di-p-nitrophenylazocalix[4]arene-calix[4]pyrrole (1) was designed and synthesized. The color of the solution of probe 1 changed upon the addition of any F(-), CH(3)CO(2)(-), PhCO(2)(-), and H(2)PO(4)(-) ions. However, from these ions the highly specific sensing of F(-) is achieved by the addition of Ca(2+) which leads to a color change from light sky blue (of 1·F(-)) back to the original light orange color of 1. 相似文献
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Thianthan Taweetanavanich Banchob Wanno Thawatchai Tuntulani Buncha Pulpoka Chatthai Kaewtong 《中国化学会会志》2019,66(5):493-499
A rhodamine‐based colorimetric and fluorescent pH chemosensor ( RhA ) was designed and synthesized via a coupling reaction between rhodamine ethylenediamine and succinic anhydride. RhA showed excellent pH response in aqueous solutions. In addition, common cations (Na+, K+, Ag+, Mg2+, Ca2+, Pb2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Al3+, Cr3+, Fe3+, Au3+, Pt2+, and Ru2+) did not interfere with the pH response. As it has the potential to be used as a portable pH sensor, RhA was immobilized on activated cellulose paper using N,N'‐dicyclohexylcarbodiimide (DCC) and N,N'‐dimethylpyridin‐4‐amine (DMAP) as the coupling reagent to obtain a composite pH sensor ( CP‐RhA ). CP‐RhA was characterized by ATR‐FTIR, UV–vis, and fluorescence spectroscopy, and by scanning electron microscopy (SEM). CP‐RhA showed a rapid response in the pH range 1–8 through color and fluorescence changes. DFT calculations showed a blue‐shifted spectrum in the protonated form compared to the neutral form. Moreover, the pH sensor paper could be reused by dipping in NaOH. Thus, our work demonstrates the potential of the rhodamine dye composite for visualizing pH changes in real systems. 相似文献
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Buncha Pulpoka Jong Sueng Kim Seung Hwan Yang Jacques Vicens 《Journal of heterocyclic chemistry》2001,38(6):1383-1385
Two novel calix[4]cryptands were synthesized from 1,3‐alternate calix[4]bis‐azacrown. “Mappemonde II” consists of one 1,3‐calix[4]bis‐azacrown wrapped by a benzo‐crown ether loop. “Mill II” is composed of two 1,3‐calix[4]bis‐azacrowns linked by two benzo‐crown ether strands. 相似文献
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Buncha Pulpoka Zouhair Asfari Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》1997,27(1):21-30
Co-receptor 1,3-calix[4]-di(aza-benzo)crown-crown-6 (1-H) designed with one calix[4]arene in a 1,3-alternate conformation and hard and soft metal ion binding sites has been prepared according to three pathways (A-C). Pathway B, consisting of two different 1 + 1 condensations with ditosylate derivatives, was shown to be the most efficient. 相似文献
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Chatthai Kaewtong Buncha Pulpoka 《Journal of inclusion phenomena and macrocyclic chemistry》2009,65(1-2):129-136
The design, synthesis and cation binding ability of azacalix[3]arene are summarized. Recent developments on its anion complexations and molecular devices are also added for better understanding. 相似文献
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Kaewtong C Fuangswasdi S Muangsin N Chaichit N Vicens J Pulpoka B 《Organic letters》2006,8(8):1561-1564
[structure: see text] We report the synthesis of a novel C(3)(v)()-symmetrical N(7)-hexahomotriazacalix[3]cryptand (1). Compound 1 was shown to be in a fixed cone conformation by (1)H NMR spectroscopy and X-ray single-crystal structure determination. Complexation studies showed that 1 is a selective receptor for halide ions. The effects of zinc metal cation on the receptor (1-Zn(2+)) upon anion recognition are also shown. 相似文献
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Kaewtong C Wanno B Uppa Y Morakot N Pulpoka B Tuntulani T 《Dalton transactions (Cambridge, England : 2003)》2011,40(46):12578-12583
Fluorescence-active chemosensors (L1-L4), comprising a rhodamine scaffold and a pseudo azacrown cation-binding subunit, have been proposed and characterized as a fluorescent chemosensor for Hg(2+). An on-off type fluorescent enhancement was observed by the formation of the ring-opened amide form of the rhodamine moiety, which was induced by the interactions between Hg(2+) and the chemosensor. Upon the addition of Hg(2+), an overall emission change of 350-fold was observed, and the selectivity was calculated to be 300 times higher than Cu(2+) for receptors L2-L4. A polymeric thin film can be obtained by doping poly(methyl methacrylate) or PMMA with chemosensor L2. Such a thin film sensor can be used to detect Hg(2+) with high sensitivity and can be recovered using diluted NaOH. 相似文献
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A series of N,N-bis(2-hydroxybenzyl)alkylamine derivatives (1–5) have been found to form host–guest compounds with transition metal ions. The inclusion phenomena in solution are confirmed from the new peak at 415?nm observed by UV-Vis (ultraviolet-visible) spectroscopy and the aromatic and methylene peak shifts observed by 1H NMR (proton nuclear magnetic resonance) spectroscopy. Comparative studies on 1–5 by liquid–liquid extraction studies suggest that the bulky group at the aza position of the derivatives obstructs the ion interaction resulting in the decrease in ion extraction ability. Inclusion depends on the interaction of the transition metal ions with the compounds 1–5 at the aza and hydroxyl groups as identified by the two-dimensional nuclear Overhauser enhancement technique (1H–1H NOESY). The results from Job's plot and electrospray ionization mass spectroscopy (ESIMS) imply molecular assembly of the host–guest system in a 2:1 ratio. Comparative studies among different ions, i.e., Cu2+, Zn2+ and Cd2+ suggest that the host–guest formation is effective when electron sharing is possible through the outer orbital of the transition metal ions. In the case of inclusion in the solid state, the FTIR (Fourier transform infrared) spectra show the changes in vibrational mode of the functional groups in host molecules whereas the X-ray diffraction (XRD) patterns suggest a change in the packing structure of the host molecules. After host–guest formation, the thermal stability of the host molecules decreases as a result of the change in the packing structure from a hydrogen-bonded network to one of ionic interaction with the guest. 相似文献
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N-benzylhexahomotriaza-p-chlorocalix[3]trinaphthylamide in partial cone conformation was selectively synthesized by appropriately controlling the steric effect during the amidation reactions of N-benzylhexahomotriaza-p-chlorocalix[3]tri(ethyl acetate) in cone or partial cone conformations with use of 1-aminomethylnaphthalene. The conformation was confirmed by (1)H, (13)C, and 2D NMR and X-ray single-crystal analysis. Analyses of the complexes revealed that recognition is strongly affected by Cd(2+), Pb(2+), and F(-) ions. 相似文献