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Calix[4]azulene     
Azulene reacts with paraformaldehyde in the presence of florisil to give excellent yields of calix[4]azulene.  相似文献   

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控制反应物的物质的量比, 杯式对叔丁基杯[4]-1,3-二乙酸乙酯衍生物1与5或50倍二乙烯三胺反应, 分别得到杯[4]氮杂冠醚2和开链的氮杂杯[4]芳烃衍生物3. 化合物2和3进一步与异硫氰酸苯酯反应得到首例侧链含硫脲基的套索杯[4]氮杂冠醚4和含4个硫脲基的杯[4]芳烃衍生物5, 产率为92%和87%. 新化合物的结构与构象经元素分析、红外、质谱、核磁共振谱等表征证实.  相似文献   

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Supramolecular chemistry is an interdisciplinary scientific field, including chemical, physical and biological properties of more complex chemical species than the molecules themselves. Calixarenes/calixresorcinarenes are macrocyclic compounds, consisting of ‘n’ phenolic/resorcinolic units linked together by methylene bridges; these macrocycles are often used for molecular recognition. Thus, different modifications can be made to both the lower and upper rim, allowing the construction of well-defined multivalent buildings. In this work, three calix[4]resorcinarene macrocycles were synthesized, namely C-dec-9-en-1-ylcalix[4]resorcinarene (CAL 11U), C-trans-2, cis-6-octa-1,5-dien-1-ylcalix[4]resorcinarene (CAL 9U) and C-nonylcalix[4]resorcinarene (CAL 10) by a simple condensation reaction. The compounds CAL 11U and CAL 10 have been already synthesized by researchers, while the CAL 9U has been synthesized for the first time. Their structures were confirmed using ATR-FTIR, 1H NMR and 13C NMR. Thermal analysis combined with mass spectrometric evolved analysis of the vapors was used to study the thermal behavior of the different synthesized molecules, and they were the subject of characterization by X-ray powder diffraction in order to analyze their degree of crystallinity.

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The synthesis of calix[4]arene based dendrimers containing up to seven calix[4]arene moieties is described, including the X-ray crystal structure of a tris-calix[4]arene branching derivative.  相似文献   

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从简单无机硫、硒化合物直接合成冠醚环上含硫、硒杂原子的杯[4]单硫杂冠-5及杯[4]单硒杂冠-5;化合物的结构经1HNMR、MS及元素分析确证.并研究了它们对Na+,K+,NH4+,Co2+,Ni2+,Ag+及Hg2+的两相萃取性能,发现其对Ag+、Hg2+有较好的识别能力.  相似文献   

11.
Ab initio STO-2G calculations showed that the preferred conformation of a series of calix[6]arenes substituted at the upper rim is a compressed cone stabilized by a pseudo-ring of six hydrogen bonds with close characteristics. The endocyclic dihedral angles between the benzene ring planes, characterizing the molecular shape of the above macrocyclic compounds in this conformation, were calculated. The calculation results are consistent with the conformational data obtained by other theoretical methods and describe the characteristics of hydrogen bonds more adequately, in agreement with the experimental data and with the existing concepts of the hydrogen bonding efficiency.  相似文献   

12.
Abstract

Single halogen atom (i. e. I, Br, Cl and F) substituted calix[4]pyrroles, compounds 2, 3, 4 and 5, were synthesized. Studies of these systems reveal that replacement of a single β-pyrrolic hydrogen atom can increase the anion binding ability of calix[4]pyrroles for a variety of anions (e. g. Cl?, Br?, H2PO4 ? and HSO? 4) relative to normal non-halogen substituted calix[4]pyrrole 1. In the case of chloride anion, the expected relative affinity sequence of 5 > 4 > 3 > 2 was observed. This was not found to be true for Br?, H2PO? 4, and HSO? 4. Here, the chlorine substituted calix[4]pyrrole 4 was found to display a slightly higher affinity in the case of each anion than the fluorine-bearing derivative 5. This was rationalized in terms of intermolecular NH … F hydrogen bonding interactions being present in CD2Cl2 solutions of 5. Support for this latter conclusion came from concentration and temperature-dependent NMR spectroscopic studies.

A matched set of mono halogen substituted calix[4]pyrroles was used to study in detail, the extent to which halogen substituents may be used to fine-tune the anion binding properties of calix[4]pyrroles.  相似文献   

13.
Synthesis and single-crystal X-ray structures of mixed triple and double calixarenes 6 and 7, obtained from the base-catalyzed condensation of calix[5]arene 1 with cone pertosylated calix[4]arene 2, are reported. VT-NMR studies on 7 are consistent with a molecular motion arising from the anti-gauche conformational interconversion of its ethylene linkages.  相似文献   

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R. Rodik  V. Boyko  O. Danylyuk  J. Lipkowski 《Tetrahedron》2007,63(46):11451-11457
The synthesis of calix[4]arenes bearing two quinazolin-4-ones group at the upper rim is decribed. 1H NMR spectra and quantum chemical calculations make it possible to suggest that calix[4]arenequinazolinones form three rotamers in solutions at room temperature, due to the restricted rotation of the quinazolinone fragments. The X-ray structure investigation indicates that quinazolin-4-onecalix[4]arene exists in the crystal state as the methanol 1:1 inclusion complex.  相似文献   

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Calixarenes are a versatile class of macrocyclic compounds, which have attracted extensive interest due to their ability to form host-guest complexes and act as enzyme mimic. Moreover, a number of calixarenes with D-π-A units have been synthesized, and their second-order nonlinear optical (NLO) properties investigated.  相似文献   

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1,3-Alternate calix[4]arene with para-phenylene spacers connecting nitroxide monoradicals and high-spin (S = 1) diradicals provides tetraradical and octaradical scaffolds that possess conformations with slow electron spin relaxation rates (1/T(1)). Such scaffolds may facilitate tuning of relaxation rates that are more favorable for MRI or DNP applications.  相似文献   

18.
1,3-diproyloxycalix[4]arene azacrown ether was successfully synthesized in the fixed 1,3-alternate conformation which was confirmed by a solid state structure.  相似文献   

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A series of calix[4]arene-supported Ln(III)(6) clusters have been synthesised under facile bench top conditions. The magnetic and structural properties of these clusters are reported, the latter suggesting that the Ln(III)-calix[4]arene moiety may be used for the construction of other assemblies in a manner akin to that for the Mn(III)-calix[4]arene analogue.  相似文献   

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