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1.
We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The crystal structures of the calix-[4]arene with two butyl amide (3b) and four butyl amide moieties (4b) were determined. The intermolecular hydrogen bonds make 4b form two-dimensional net work insolid state. The 1H NMR spectra prove that 3b is of a pinched cone conformation, while 4b and tetraheptylamide-calix[4]arene (6b) take fast interconversion between two C2v isomers in solution and appear an apparent cone conformation at room temperature. As decreasing temperature, the interconversion rate decreases gradually and, finally, the interconversion process is frozen at Tc = -10℃, which makes both conformations of 4b and 6b the pinched cone structures. The hydrogen bond improves the interconversion barrier, and the large different values of the potential barrier between 6b and 4b (or 6b) may 相似文献
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A new idea of the nanorods preparation and a novel application of calixarenes are presented. Calix[4]arene was introduced
into solvothermal system to produce one-dimensional inorganic nanomaterial. The obtained product was characterized by XRD
and TEM. Results of the XRD analysis showed that the product was pure cubic phase of PbS with high crystallinity. TEM images
revealed that the diameter and length of the PbS nanorods were about 200 nm and up to 3.5 μm, respectively. Optical properties
of the product were also studied. PL emission image showed that the product exhibited an emission peak at 308 nm in ultraviolet
region showing a blue shift of 14 nm compared to the bulk material. The formation mechanism of PbS nanorods in the presence
of calix[4]arene is discussed. 相似文献
4.
Tian-Ming Y Zhi-Feng Y Li W Jin-Ying G Si-De Y Xian-Fa S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(14):3033-3038
The catalysis effect of water-soluble calix[4]arene C[4] (calix[4]arene-5,11,17,23-tetrasulfonate) on hydrolysis of ATP in aqueous solution was studied by HPLC. Using laser photolysis and pulse radiolysis, the supramolecular interaction between water-soluble calix[4]arene and ATP was investigated. 相似文献
5.
Shobhana K. Menon Ravindra V. Patel Jayesh G. Panchal 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(1-2):73-79
A series of azocalix[4]arene dyes (1–7) were prepared by linking 2,4-di-chloroaniline, 2,4,5-tri-chloroaniline, 2,4-di-nitroaniline, 2-nitro p-toluidin, 4-nitro o-toluidin, 5-nitro o-toluidin and sulfanilic acid, to calix[4]arene through a diazo-coupling reaction. These compounds were characterized by elemental analysis, FT-IR, 1H NMR, 13C NMR, MALDI-TOF, UV–Vis., DSC, and DTA. The absorption properties of the synthesized dyes were studied and the application of the water soluble dye on cotton and wool was discussed. Solvent based inks were investigated and the fastness properties of formulated inks were also discussed. 相似文献
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[structure: see text] The synthesis of a Pacman heterobisporphyrin associating an octaethyl porphyrinatozinc (ZnOEP) energy donor and a triaryl porphyrinatozinc (ZntPP) energy acceptor around a calix[4]arene spacer is described. Contrary to previous symmetrical architectures, correlations between the chromophores in the unsymmetrical calixarene bisporphyrin Pacman scaffold can now be observed in ROESY experiments. Independent of the excitation wavelength, only the luminescence of the ZntPP moiety was observed corresponding to quenching of the OEP moiety's emission. 相似文献
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K. Chennakesavulu M. Raviathul Basariya G. Bhaskar Raju S. Prabhakar 《Journal of Thermal Analysis and Calorimetry》2011,103(3):853-862
Thermal decomposition kinetics of calix[6]arene (C6) and calix[8]arene (C8) were studied by Thermogravimetry analysis (TG)
and Differential thermal analysis (DTA). TG was done under static air atmosphere with dynamic heating rates of 1.0, 2.5, 5.0,
and 10.0 K min−1. Model-free methods such as Friedman and Ozawa–Flynn–Wall were used to evaluate the kinetic parameters such as activation
energy (E
a) and pre-exponential factors (ln A). Model-fitting method such as linear regression was used for the evaluation of optimum kinetic triplets. The kinetic parameters
obtained are comparable with both the model-free and model-fitting methods. Within the tested models, the thermal decomposition
of C6 and C8 are best described by a three dimensional Jander’s type diffusion. The antioxidant efficiency of C6 and C8 was
tested for the decomposition of polypropylene (PP). 相似文献
10.
Yong Xia 《Supramolecular chemistry》2013,25(1):32-38
Theoretical studies of a diquinone calix[4]arene and its interactions with the cations Li+, Na+, K+ and Ag+ have been performed. Conformational features and cation-binding properties were evaluated with the restricted hybrid Becke three-parameter exchange functional method using the 6-31G(d) basis set and its relativistic effective core potentials. To model the effect of medium, the polarisable continuum model was also used. Four typical conformations of the parent diquinone calix[4]arene were studied. The calculated results show that the most stable conformers are 1,3-alternate and partial cone in the gas phase and in CH2Cl2 solution, respectively. The optimised geometric structures were used to perform natural bond orbital analysis. The two main types of driving force metal–ligand and cation–π interactions are investigated. The calculated binding energy for cations (Li+, Na+, K+ and Ag+) is discussed. The calculated results indicate that cone complexes are the most stable. 相似文献
11.
Hasalettin Deligz Mustafa Tavasli Mustafa Yilmaz 《Journal of polymer science. Part A, Polymer chemistry》1994,32(15):2961-2964
A polymeric compound containing more than one calixarene molecule was synthesized by reacting the oligomer ( 2 ) with 25,26,27-tribenzoyloxy-28-hydroxy calix[4]arene. After basic hydrolysis of 3a , the polymeric calixarene ( 3b ) was utilized for selective extraction of some metal cations from aqueous phase to organic phase. It was found that the compound ( 3b ) was selective toward Fe3+ from an aqueous solution containing Cu2+, Ni2+, Co2+ and Fe3+ cations. The mechanism of the extraction process was discussed. © 1994 John Wiley & Sons, Inc. 相似文献
12.
Shivanyuk A 《Journal of the American Chemical Society》2007,129(46):14196-14199
A hexameric resorcinarene nanocapsule in wet CDCl3 forms inclusion complexes of calix[4]arene with tetramethylammonium and trimethylsulfoxonium cations to give highly stable Russian-doll-type multicomponent assemblies. The 2D NOESY experiments revealed the size of the assembly, the close proximity of the encapsulated calix[4]arene molecule to the resorcinarene molecules of the capsule, and the inclusion of the tetramethylammonium cation in the calix[4]arene cavity. 相似文献
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New types of lower rim proximally bridged thiacalix[4]arenes have been prepared by direct aminolysis of starting tetraacetate derivative in the cone conformation using aliphatic α,ω-diamines. X-ray crystallography revealed the highly preorganized array of -C(O)NH- bonds resulting in strong intramolecular hydrogen bonding between amide groups of both bridges. The length of the corresponding diamine was found to have an essential influence on the yield of these bridged molecules. 相似文献
15.
Giuseppe Arena Francesco Attanasio Dongmei Zhang Yanfei Yang Richard A. Bartsch Carmelo Sgarlata 《Analytical and bioanalytical chemistry》2013,405(2-3):1133-1137
A fluorogenic derivative of a calix[4]arene with two proton-ionizable N-(phenyl)sulfonyl carboxamide-containing side arms in the 1,3-positions on the lower rim is employed for the selective sensing of Hg2+ at low concentration levels in water/MeCN (1:1, v/v) solutions containing Pb2+ and Cd2+. All three metal ions quench the fluorescence of the ligand in pure MeCN. However, in water/MeCN mixed solvent, the recognition of such cations occurs differently as only Hg2+ complexation quenches the fluorescence of the calixarene. Experiments carried out in the presence of an acid and a bulky non-complexing cation shows that the quenching of the calixarene fluorescence upon Hg2+ addition is likely due to proton displacement from the proton-ionizable side arms of the ligand. The system may be employed as a simple tool for the selective and efficient mercury sensing in mixed water/organic solvent. 相似文献
16.
Junyan Zhan Xiaolei Zhu Fei Fang Fajun Miao Demei Tian Haibing Li 《Tetrahedron》2012,68(27-28):5579-5582
Novel naphthyl-modified calix[4]arene was synthesized by click chemistry, and exhibited high affinity and selectivity for p-nitroaniline by the fluorescence spectroscopy. However, the sensitivity toward other anilines 3a–e are negligible. The 1H NMR, 1H NOESY, MALDI-TOF mass spectroscopy and computational calculations revealed the formation of host–guest complex driven by H-bonding and hydrophobic interactions. 相似文献
17.
Furer VL Borisoglebskaya EI Kovalenko VI 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(1-2):355-359
The experimental IR and Far IR spectra of the calix[4]arene, p-tert-butylcalix[4]arene, thialcalix[4]arene and p-tert-butylthiacalix[4]arene were examined at different temperatures and interpreted. The band frequencies and intensities in the IR spectra of the calix[4]arene and thialcalix[4]arene were calculated. The absorption curves of the four possible calix[4]arene conformations: cone, partial cone, 1,2- and 1,3-alternate were computed. The bands characteristic for each conformation are defined and assigned. The obtained spectra-structure correlation can be used for the characteristic of calixarenes conformation. 相似文献
18.
Langxing Chen Xianshun Zeng Xiwen He Zhengzhi Zhang 《Analytical and bioanalytical chemistry》2000,367(6):535-538
Silver ion-selective electrodes were prepared with polymeric membranes based on two calix[4]arene derivatives functionalized by two hydroxy and two benzothiazolylthioethoxy groups. The electrodes all gave a good Nernstian response of 58?mV decade–1 for silver in the activity range 5 × 10–6–10–1 M, the limits of detection reached 10–5.8 M and exhibited high selectivity towards alkali, alkaline earth and some transition metal ions. The electrode was used as indicator electrode in titrations of Ag+ with Cl– ion. 相似文献
19.
Jerry L. Atwood Anthony W. Coleman Hongming Zhang Simon G. Bott 《Journal of inclusion phenomena and macrocyclic chemistry》1989,7(2):203-211
The title calixarenes all exist in the solid state as bilayers of anionic calixarenes in the cone configuration. These layers alternate with inorganic regions which contain the cations and the water molecules. The overall structures bear a close resemblance to those found for clay minerals. The sodium salt crystallizes in the triclinic space groupP witha = 10.998(6),b = 13.582(5),c = 14.472(5) Å, = 74.01(3), = 89.09(4), = 86.50(4)°, andZ = 2 forD
calc
= 1.72 g cm–3. Refinement based on 4727 observed reflections led to a conventionalR = 0.050. The potassium salt crystallizes in the triclinic space groupP witha = 11.815(9),b = 13.636(6),c = 14.040(9) Å, = 100.24(5), = 111.86(9), = 95,14(9)°, andZ = 2 forD
calc
= 1.77 g cm–3. Refinement based on 2977 observed reflections led toR = 0.15. The rubidium and cesium salts are isostructural and crystallize in the monoclinic space groupP21/n with parameters for Rb[Cs]a = 11.603(5) [11.704(3)],b = 28.607(8) [29.747(9)],c = 12.512(5) [12.604(4)] Å, = 91.70(4) [91.63(2)°], andZ = 4 forD
calc
= 2.01 [2.24] g cm–3. Refinement based on 1750 [4257] observed reflections led toR = 0.108 [0.075]. Disorder of the cations was observed for the rubidium and cesium salts.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82074 (95 pages). 相似文献
20.
Regioselective synthesis of calix[4]arene 1,3-di- and monosubstituted sulfur-containing Schiff bases
Jing Sun Dong Mei Liu Jin Xiang Wang Chao Guo Yan 《Journal of inclusion phenomena and macrocyclic chemistry》2009,64(3-4):317-324
Regioselective alkylations of p-tert-butylcalix[4]arene with 3-methoxy-4-ω-chloroalkoxy-benzaldehydes in the system of K2CO3/KI/CH3CN efficiently produce 1,3-di- and monosubstituted aldehydes according to the length of alkyl chains in alkylating reagent, which provides a versatile protocol for preparing calixarene 1,3-di- and sulfur-containing Schiff bases. 相似文献