Study of neutral species coordination by macrocyclic anion receptors using FTIR spectroscopy

Complexation ability for two various macrocyclic receptors applied previously as anion receptors to poly(ethylene oxide)-based solid polymer electrolytes was studied by means of FTIR spectroscopy. We have proved that the interactions between neutral species (solvent) and receptors depend both on the donor properties of the solvent and type of the functional groups in receptor. For solvent characterized by similar dielectric constant and coordinating properties (donor and acceptor numbers) like 1,2-dimethoxyethane and its high molecular weight analogues-poly(ethylene oxide) interactions are also affected by steric effect.     

Selective Ion Transport and Complexation in Layer‐by‐Layer Assemblies of p‐Sulfonato‐ calix[n]arenes and Cationic Polyelectrolytes

The first study of ion transport across self‐assembled multilayered films of p‐sulfonato‐calix[n]arenes and poly(vinyl amine) (PVA) is presented. The films are prepared by the alternate electrostatic layer‐by‐layer assembly of the anionic calixarenes and cationic PVA on porous polyacrylonitrile (PAN) supports. We use tetra‐p‐sulfonato‐calix[4]arene (calix4), hexa‐p‐sulfonato‐calix[6]arene (calix6), and octa‐p‐sulfonato‐calix[8]arene (calix8) as the calixarenes. Ultraviolet (UV) studies indicate that dipping solutions of pH 6.8, without a supporting electrolyte, are most suited for film preparation. Calix8 is adsorbed in higher concentrations per layer than calix6 or calix4, probably because desorption is less pronounced. The permeation rates, P_Rs, of monovalent alkali‐metal chlorides (Li, Na, K, Cs), magnesium chloride, divalent transition‐metal chlorides (Ni, Cu, Zn), trivalent lanthanide chlorides (La, Ce, Pr, Sm), and sodium sulfate across the calix4/PVA, calix6/PVA, and calix8/PVA membranes are studied and compared with the corresponding P_R values across a poly(styrene sulfonate) (PSS)/PVA multilayer membrane prepared under the same conditions. The P_R values of the alkali‐metal salts are between 4 and 17 × 10^–6 cm s^–1, those of magnesium chloride and the transition‐metal salts are 0.2–1.3 × 10^–6 cm s^–1, and those of the lanthanide salts are about 0.1 × 10^–6 cm s^–1. Possible origins for the large differences are discussed. Ion transport is first of all controlled by electrostatic effects such as Donnan rejection of di‐ and trivalent ions in the membrane, but metal‐ion complexation with the calixarene derivatives also plays a role. Complexation occurs especially between Li⁺ or Na⁺ and calix4, Mg²⁺, or Cu²⁺ and calix6, Cu²⁺, Zn²⁺, or the lanthanide ions and calix8. Divalent sulfate ions are found to replace the calixarene polyanions in the membrane. UV studies of the permeate solutions indicate that calix4 especially is displaced during sulfate permeation.     

杯芳烃的配位化学Ⅲ．乙酰基甲氧基对叔丁基杯［4］芳烃的合成及对金属的萃取

合成了对叔丁基杯［４］芳烃及其衍生物乙酰基甲氧基对叔丁基杯［４］芳烃（简称Ｌ）。研究了萃取剂Ｌ对各种金属离子的萃取，发现该试剂对Ｎａ￣＋有特殊的萃取效率，测定了Ｌ萃取Ｎａ￣＋的萃取平衡常数，并讨论了其萃取机理。     

Photocurrent and hydrogen production by overall water splitting based on polymeric composite Calix[n]arene/Cyanin Dye/IrO2 nanoparticle

In this study, a new photoelectrochemical cell based on overall splitting of water into oxygen and hydrogen is constructed to obtain an improved photocurrent under a visible range of light. The photoanode was obtained by a gold electrode (GE) modified with carboxylic acid functionalized SH-Calix-4-arene-COOH and IrO₂ nanoparticles attached light absorbing cyanine dye via polymeric oligoaniline linkages. The conductive polymer, 4- (4H-Dithieno [3,2-b: 2 ′, 3′-d] pyrrol-4-yl)aniline, was coated on GE using electropolymerization and used as a photocathode after platinum nanoparticles (Pt) were attached on the surface. The system was illuminated under the visible light, and the water was oxidized via IrO₂ catalyst to produce hydrogen on the photocathode side while oxygen on the photoanode. A photocurrent density of 182.03 μA cm⁻² was obtained by direct transfer of electrons without using a mediator. The bilirubin oxidase (BOx) enzyme was successfully used to remove excess oxygen from the reaction chamber and a further increase in photocurrent was reached up to 272.44 μA cm⁻². Hydrogen production in the reaction chamber was measured by gas chromatography at different time intervals and a maximum of 1.25 × 10⁻⁸ mol cm⁻² was obtained.     

杯芳烃及其衍生物在色谱分离中的应用

杯芳烃是由多个苯酚在 2 ,6位通过亚甲基相连形成的大环化合物。它是继环糊精和冠醚之后的第三代超分子物质 ,兼有环糊精、冠醚之所长 ,具备更高的选择性。其分子识别功能在现代分离科学中有着广泛的应用。本文对其在色谱分离中的应用进行了综述和展望     

Monolayer behavior of calix-4-resorcinarenes and their surfactant complexes

We describe within this paper a series of calix-4-resorcinarenes along with their complexes with tetraalkylammonium surfactants and their behavior in Langmuir monolayers. Calix‐4‐resorcinarenes were synthesized containing both undecyl and phenyl sidechains and then modified using Mannich reactions to incorporate neutral, cationic or anionic groups in the 2‐positions of the resorcinol unit. In the cases of resorcinarenes modified with four sulfonate groups, mixing with long chain dialkyl dimethyl ammonium surfactants led to the formation of 1:4 complexes. These various materials were spread as Langmuir monolayers and their behavior upon compression measured. Long chain substituted resorcinarenes gave more stable monolayers than their short chain analogues. The incorporation of long chain surfactants led to large increases in surface area, demonstrating that both resorcinarenes and surfactant are located at the water surface, except for one system where a bilayer structure is potentially formed.     

杯芳烃合成研究进展

杯芳烃是一类超分子主体化合物,主要有杯[4]、杯[6]和杯[8]芳烃的杯芳烃衍生物、杯芳烃聚合物及杯芳烃配合物等。介绍了不同杯芳烃及其衍生物的合成工艺的研究进展。     

杯芳烃BEHBCalixC6萃取低浓度Cs^＋研究

杯芳烃BEHBCalixC6对低浓度Cs^＋有较好的萃取性能。实验表明用二氯甲烷做稀释剂时萃取效率最高,且萃取效率随着主客体摩尔比增大而增大。并研究了酸度对萃取效率的影响及杯芳烃BEHBCalixC6的重复回收使用。     

Novel phosphinoxide-bearing ligands and their photoluminescent complexes: Spectroscopic studies

Several novel phosphinoxide ligands have been prepared, based on molecular frameworks: pyridine, 2,2′-bipyridine, cavitands, cyclotriphosphazene and 1,3,5-triazine. These compounds form highly luminescent complexes with Eu(III) and Tb(III). Excellent luminescent properties were observed in case of pyridine and 2,2′-bipyridine ligands with photoluminescence quantum yields approaching 25%. Cavitand-based phosphinoxides turned out to be rather poor sensitisers for the lanthanide ion emission. Particularly long emission lifetime was observed in case of pyridine P-oxide complexes of Eu(III) and Tb(III), exceeding 3 ms.