Preparation and characterization of p-tert-butyl thiacalix[4]arene imbedded flexible polyurethane foam: An efficient novel cationic dye adsorbent

In this study, a new type of flexible polyurethane foam containing p-tert-butyl thiacalix[4]arene (TC4A) macrocycle was synthesized. TC4A macrocycle was incorporated into polyurethane foam as a part of crosslinking agent as well as glycerol. Structural, morphological, thermal and mechanical properties of this prepared foam were studied and compared with a polyurethane foam based on only glycerol as crosslinking agent, by Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), Thermal gravimetric analysis (TGA), and dynamic mechanical thermal analysis (DMTA). The effect of introduction of TC4A crosslinker on cream time, rise time, apparent density, and water absorbency of the PU foams was evaluated. Moreover, it was shown that new TC4A-based polyurethane foam (TC-PUF) can be a high performance adsorbent for removal of malachite green from aqueous media using batch adsorption technique. The adsorption results indicated that TC-PUF has a high adsorption capacity of 58.82 mg/g for malachite green due to the presence of TC4A macrocycles in the structure of polyurethane foam. The kinetics of adsorption of malachite green was also investigated using the pseudo-first-order and pseudo-second-order kinetic models. The results of kinetic studies showed that the adsorption of malachite green onto TC-PUF followed pseudo-second-order kinetic model.     

Electroanalytical studies on cadmium(II) selective potentiometric sensors based on t-butyl thiacalix[4]arene and thiacalix[4]arene in poly(vinyl chloride)

Cd²⁺-selective sensors have been fabricated from poly(vinyl chloride) (PVC) matrix membranes containing t-butyl thiacalix[4]arene (I) and thiacalix[4]arene (II) as electroactive materials. The addition of sodium tetraphenylborate and the plasticizer 2-nitrophenyl octyl ether has been found to improve the performance of the sensors substantially. The membranes of various compositions of the two thiacalixarenes have been investigated and it was found that the best performance was obtained for the membrane of composition II:PVC:NaTPB:NPOE in the ratio 5:120:3:150. The sensor shows a linear potential response for Cd²⁺ over a wide activity range 3.2 × 10⁻⁶ to 1.0 × 10⁻¹ M with Nernstian compliance (29.5 mV decade⁻¹ of activity) in pH range 4.5-6.5 and a fast response time of ∼8 s. The potentiometric selectivity coefficient values determined by matched potential method indicate excellent selectivity for Cd²⁺ ions over mono-, di- and trivalent interfering cations. The sensor exhibits adequate shelf life (∼3 months) with good reproducibility (S.D. ±0.2 mV) and can also be used in partially non-aqueous media having up to 20% (v/v) methanol, ethanol or acetone content with no significant change in the value of slope or working activity range. The sensor has been used in the potentiometric titration of Cd²⁺ with EDTA. The sensor could be successfully used for the quantification of cadmium in river water samples.     

对叔丁基杯[4]及杯[6]芳烃的合成及其对铜离子的萃取研究

以对叔丁基苯酚和甲醛为原料,分别对对叔丁基杯[4]及杯[6]芳烃的合成和萃取性质进行了研究．结果表明,在本研究范围内,以KOH为催化剂,对叔丁基杯[6]芳烃的最高产率为77．8％;以NaOH为催化剂,对叔丁基杯[4]芳烃的最高产率为47．3％。对于对叔丁基杯[4]和杯[6]芳烃,最佳的反应回流温度都为140℃。对叔丁基杯[6]芳烃对模拟废水中的铜离子具有一定的萃取效果,最高萃取率为70．3％。     

相转移催化合成四乙酰氧基对叔丁基杯[4]芳烃

以聚乙二醇(PEG)600为相转移催化剂合成四乙酰氧基对叔丁基杯[4]芳烃。实验结果表明：当对叔丁基杯[4]芳烃1．0g,乙酸酐9mL,0．0224g浓98％H2SO4(质量分数)和0．4gPEG600,回流反应20min,产率达到75．1％。     

氮杂杯[6]芳烃的合成与表征

以三聚氯氰和对苯二胺为原料,碳酸钾或氢氧化钾作为缚酸剂,合成氮杂杯[6]芳烃第一步中间体N,N’-二(4,6-二氯-1,3,5-均三嗪-2-基)-1,4-苯二胺(Ⅰ)和第二步中间体2,4-二(4-胺基苯胺基)-6-氯-1,3,5-均三嗪(Ⅱ),再由(Ⅰ)和(Ⅱ)合成最终产物氮杂杯[6]芳烃。通过红外光谱分析法和核磁共振氢谱法对产物进行了表征,证实其为目标产物,从而验证了合成路线的可行性。     

羧基苯偶氮基杯[4]芳烃衍生物的合成、表征及光谱特性

以邻、间、对氨基苯甲酸和杯 [4]芳烃为原料 ,经重氮化 -偶联反应合成了发色邻、间、对羧基苯偶氮基杯 [4]芳烃 ,产物的结构经 IR,1H NMR和元素分析表征 ;研究了它们的生色原理和光谱性能。结果表明它们是一类新型指示剂和具有新型配位空腔的主体分子。     

Poly (acrylic acid-co-acryloyl tetrasodium thiacalix[4]arene tetrasulfonate) grafted dextrin: new supper metal ion adsorbing hydrogels

Dextrin as a biodegradable natural polymer has hydrophilic nature that capable to increase the swelling properties and biodegradability of the synthetic hydrogels. This study describes the synthesis of a poly (acrylic acid-co-acryloyl tetrasodium thiacalix[4]arene tetrasulfonate) grafted dextrin superabsorbent hydrogels (ADA) via solution polymerization. The effects of acryloyl tetrasodium thiacalix[4]arene tetrasulfonate (ACSTCA) dose (20–60) on swelling properties of the hydrogels were studied. The synthesized hydrogels were characterized by FTIR, TGA, DMTA and rheometry. The metal ion removal capacity of the gels was investigated by atomic absorption for Cd²⁺, Pb²⁺, and Hg²⁺. The tendency of metal ions adsorption decreased in the order of Pb²⁺>Cd²⁺>Hg²⁺. The effect of key operating parameters including ACSTCA content, contact time, adsorbent dosage, solution pH, and crosslinker density was experimentally studied on Pb²⁺ adsorption from aqueous solution. The equilibrium data was analyzed using Langmuir and Freundlich adsorption isotherms. Our experimental data are in best agreement with Freundlich isotherms, and adsorption of metal cation onto hydrogel followed a pseudo second-order kinetic model. According to the thermodynamic parameters, the adsorption of Pb²⁺ occurred spontaneously. The hydrogels could be regenerated after releasing heavy metal ions, and reused 5 times with less than 7 % loss of adsorption capacity.     

Synthesis and Antimicrobial Activity of p-tetranitrocalix[4]arene Derivative

The present study demonstrates the synthesis and antimicrobial activity of the p-tetranitrocalix[4]arene (3). The microbial activity was determined against a variety of microorganisms, i.e., Gram-positive and Gram-negative bacterial strains such as Staphylococcus aureus ATCC 10231, Streptococcus viridans ATCC 12392, Escherichia coli ATCC 8739, as well as some fungal species including Aspergillus niger ATCC 16404, Aspergillus flavus ATCC 90906, and Candida albicans ATCC 32333. Kirby-Bauer well agar diffusion method was employed for the determination of antimicrobial activity. All the microorganisms were applied to a selective agar medium (Mueller Hinton Agar) for growth. It was observed that compound 3 is considerably effective against selected microorganisms. The MIC values were also evaluated. Thus, from the results it could be deduced that compound 3 may be a valuable addition to the therapeutic index.     

氨基硫脲基新型杯[4]芳烃衍生物的合成

通过1,3-环氧丙基杯[4]烃与硫代氨基脲开环反应,合成硫代氨基脲基杯[4]芳烃衍生物,研究了其对阳离子的吸附性能后发现,与其他氨基杯芳烃相比,该衍生物对铜离子的吸附性能较好,并且有很好的选择性。     

氮杂杯[6]芳烃迭氮化衍生物的合成与表征

以氮杂杯[6]芳烃和迭氮化钠为原料,四氢呋喃为溶剂,在为40~45℃合成了氮杂杯[6]芳烃迭氮化衍生物,通过薄层色谱分析法、红外光谱分析法和核磁共振氢谱法对产物进行了表征,证实其为目标产物,从而验证了合成路线的可行性。     

对叔丁基杯[4]芳烃巯基吡啶衍生物的合成

以对叔丁基苯酚为起始原料,通过缩合得到对叔丁基杯[4]芳烃,再对其下沿酚羟基进行化学改性,得到具有化学活性的杯[4]衍生物中间体,该中间体与具有活泼氢的2-巯基吡啶反应制得新的含N、S杯芳烃衍生物,总收率14.4%。     

蒽醌冠醚双功能化杯[4]芳烃的合成与表征

以对叔丁基杯[4]芳烃为原料,经碱催化两步合成了26,28-双（2-亚甲基蒽醌）-5,11,17,23-四叔丁基杯[4]-25,27-冠-6。产物经IR、1HNMR表征和元素分析表征,该衍生物为锥形结构并与设计思想一致。     

硫代杯[4]冠-4在硝酸体系中对Sr2+的萃取

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、¹H NMR和MS对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH₂Cl₂为稀释剂,在硝酸浓度为3 mol·L^-1,有机相中硫代杯[4]冠-4浓度为1×10^-3 mol·L^-1,水相中Sr²⁺浓度为5×10^-4 mol·L^-1,萃取温度为25℃,萃取80 min条件下,平均传质系数为1.36×10^{-5 m}·s^-1,Sr²⁺的分配比为0.69。分析了不同条件对硫代杯[4]冠-4对Sr²⁺的萃取影响,研究了萃取计量方程式,实验结果表明萃合物为{Sr(NO₃)₂}·{TCACE}。研究了TCACE对其他金属离子Mo⁶⁺、Ni²⁺、Ag⁺、Sn⁴⁺等的萃取效果,表明对Sr²⁺具有较好的选择性。     

芘冠醚双功能化杯[4]芳烃的合成与表征

以杯[4]芳烃为原料,经碱催化合成了26,28-双(1-乙酰基芘)-5,11,17,23-四叔丁基杯[4]-冠-6,产物结构经IR、1HNMR和元素分析表征。该衍生物为锥形结构。     

Thermal Behaviors of Bisazocalix[4]arene Derivatives

In this article, calix[4]arene (4) was prepared by debutylation and hydrolyses reacting from 25,27-dibenzoyl-26,28-dihydroxy-5,11,17,23-tetra(tert-butyl)calix[4]arene (2). Azocalix[4]arenes (6a-c) were coupled by linking 4-methoxy, 4-ethyl, and 4-nitroaniline to calix[4]arene (4) through a diazo-coupling reaction. Thermal behavior characteristics and decomposition routes of 25,26,27,28-tetrahydroxy-11,23-di(tert-butyl)-5,17-(p-substitue phenyl)azocalix[4]arene (6a-c) were investigated in air atmosphere by means of thermogravimetry (TG), differential thermogravimetry (DTG), and differential thermal analysis (DTA) analyses. It was found that the decomposition of all compounds complete with two exothermic stages which corresponded to removal of substitute groups (methoxy-, ethyl-, nitro-) and second stage rest of structure decomposition.     

杯[4]芳烃巯基吡啶衍生物的合成

以对叔丁基苯酚为起始原料,通过缩合得到对叔丁基杯[4]芳烃,再对其下沿酚羟基进行化学修饰,得到具有化学活性的杯[4]衍生物,该化合物与具有活泼氢的4巯基吡啶反应制得新的含N、S杯芳烃衍生物,总收率15.3%。     

A Convenient Approach Toward Fluoride Sorption by Calix[4]arene Based Sorbent

The present study describes the sorption of fluoride on a potential and newly synthesized p-tetraaminocalix[4]arene based resin (p-TAC4 resin). The p-TAC4 resin was synthesized via immobilization of p-tetranitrocalix[4]arene (p-TNC4) onto the Merrifield resin followed by catalytic reduction with SnCl₂/EtOH/HCl. The p-TNC4 and p-TAC4 resins were characterized using FT-IR, elemental analysis, and scanning electron microscopy (SEM). Fluoride removal capability from the aqueous media of the p-TAC4 resin has been evaluated through batch sorption study. The effect of pH, sorbate concentration, sorbent dosage, and contact time on fluoride removal was evaluated. The Langmuir (L), Freundlich (F), and Dubinin–Radushkevich (D-R) isotherms revealed that the fluoride on p-TAC4 resin follows physiosorption mechanism. All the results support and emphasize that the p-TAC4 resin is an effective sorbent for the removal of fluoride from the aqueous environment at a wide range of pH. The study may confer its impact on human health, reinstate polluted sites and other fields such as analytical, clinical, as well as material sciences.     

对叔丁基杯[6]芳烃合成

以对叔丁基苯酚和甲醛为原料,KOH为催化剂,合成对叔丁基杯[6]芳烃。探讨了催化剂用量、升温速率(从加热到回流所用的时间)、回流温度等因素对叔丁基杯[6]芳烃产率的影响,并从反应机理方面进行了讨论。结果表明,以10 g对叔丁基苯酚为原料,催化剂用量1.6 g,升温速率2 h,回流温度140℃时,产率达到90%。     

杯[4]芳烃咪唑盐的微波合成及在氟化反应中的应用

以杯[4]芳烃为起始原料,首先制得中间体杯[4]芳烃双溴代烷基衍生物,然后经微波辐射和阴离子交换,共得9种杯[4]芳烃咪唑盐衍生物,化合物的结构与构象经元素分析、IR、1HNMR、19FNMR、31PNMR表征.研究了它们在对氯硝基苯氟化反应中的催化性能以及对K+的萃取性能.结果表明,这9种化合物在氟化反应中的催化效果良好,对氟硝基苯的收率为80.89％～92.67％;同时化合物对K+具有较好的萃取效果,其中以化合物25,27-二[4-(3-甲基咪唑)乙氧基]-26,28-二羟基-5,11,17,23-四叔丁基杯[4]芳烃六氟磷酸盐的萃取效果最好,萃取率可达75.45％.