Chlorination of Calix[4]arene Derivatives

New convenient method for synthesis of p-chlorinated calix[4]arenes is reported. The sulfuryl chloride was used for chlorination of unsubstituted at the lower rim calix[4]arenes. The products of this reaction were very suitable for further O-alkylation.     

Novel Calix[4]arene Azacrown Ether

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.     

N-硫脲基套索杯[4]冠醚与四硫脲基杯[4]芳烃的合成

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.     

Calix[4]arene based neutral receptor for dihydrogen phosphate anion

A series of novel calix[4]arene hydrazone and semicarbazone based neutral receptors have been synthesized and characterized by IR, UV-vis, and NMR spectroscopies. The preliminary UV-vis and ¹H NMR titration experiments revealed that 25,26,27,28-tetrapropoxycalix[4]arene tetra-semicarbazone can recognize H₂PO₄⁻ through a 1:1 binding-stoichiometry in preference over other anions (Cl⁻, Br⁻, I⁻, HSO₄⁻, ClO₄⁻, and CH₃COO⁻).     

Calix[4]arene based molecular probe for sensing copper ions

A novel calix[4]arene based molecular probe for metal ions has been designed, synthesized and evaluated. Studies on its binding with different metal ions reveal a noticeable naked eye color change, bathochromic shift in absorption spectrum and remarkable enhancement in fluorescence emission in the presence of Cu²⁺ only. The role of calix[4]arene scaffold for selective recognition of Cu²⁺ has been demonstrated by repeat evaluation and analysis of an appropriate reference molecule. A rational explanation for fluorescence enhancement in 3 on interaction with copper has been suggested.     

Potassium Sensing Calix[4]arene Crown Ethers

1,3-Alternate calix[4]arene crown-5 (1) and corresponding biscrown-5 (2) were synthesized and the complexation behavior with alkali metal ions examined. For both 1 and 2, potassium ion was selectively extracted from aqueous phase into organic phase over other alkali metal ions based on two phase extraction experiment. The complexation ratio between calix[4]arene biscrown-5 (2), in which two crown cavities connect to the calix[4]arene framework by 1,3-alternate fashion and potassium metal ion is found to 1:1 by proton NMR spectroscopy and extraction equilibria. Association constants (logK_a) for 1 and 2 were determined to give 2.51 and 3.49, respectively.     

基于杯[4]芳烃的手性识别*

手性杯芳烃是一类重要的主体化合物,在手性识别、对映体分离和不对称催化等方面有着广泛的用途。[4]芳烃引其稳定的构象和易于修饰的特点,成为研究最为广泛的杯芳烃分子,其中大量的文献报道了能够用于对映体识别和检测的手性[4]芳烃。在手性识别的研究中,荧光、紫外和核磁是3中最常见的研究方法,本文根据这3种方法进行分类,综述了近年来以杯[4]芳烃为分子骨架的手性受体的合成及其在手性识别中的应用。最后对手性[4]芳烃的发展前景作了展望。     

四硫脲基杯[4]芳烃衍生物的合成

对叔丁基杯[4]-1,3-二乙酸乙酯与过量的二乙基三胺反应,生成含有游离氨基的杯芳烃酰胺衍物(2),2再与异硫氰酸苯酯反应合成了含4个硫脲基的杯[4]芳烃衍生物,其结构经1H NMR,IR,MS和元素分析表征。     

杯[4]芳烃四丁醚的选择性硝化

硝化反应;杯[4]芳烃四丁醚的选择性硝化     

Calix[4]arene nitroxide tetraradical and octaradical

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.     

Calix[4]arene based selective fluorescent chemosensor for organic acid recognition

A novel calix[4]arene-based fluorescent chemosensor bearing a 2-aminopyridine moiety and a naphthalenic fluorophore was synthesized The chemical structure of the product was elucidated by FT-IR, MS-FAB, NMR and elemental analyses. Then, the properties and identification mechanism of the synthesized chemosensor were investigated. The results show that the chemosensor exhibits selective fluorescent quenching in the presence of aromatic organic acid in acetonitrile solution, and that the binding ability of the chemosensor with organic acid is in the order of p-cyanic-benzyl acid > p-chloric-benzyl acid > p-methoxyl-benzyl acid > benzyl acid. __________ Translated from Journal of South China University of Technology (Natural Science Edition), 2007, 35(4): 20–24 [译自: 华南理工大学学报(自然科学版)]     

New Calix[4]arene Based Hydroxystyryl Cyanine Dyes

Calix[4]arene derivatives bearing one or two hydroxystyryl cyanine chromophores at the wide rim of the macrocycle have been synthesized. The influence of bases and Li⁺ on the UV–Vis spectra of the compounds obtained has been investigated.     

新型杯[4]芳烃衍生物的合成

以对叔丁基杯[4]芳烃为起始原料,通过一步或两步取代反应合成了对叔丁基杯[4]芳烃的衍生物(1和2),其结构经FT-IR,^1H NMR,FAB-MS表征．     

Synthesis of New Rigid Dimeric Calix[4]arene

A new Dimeric calixarene from the head to head linkage of two calix[4]arene units fixed in the cone conformation was synthesized via Sonogashira cross-coupling reaction. The structure of 10 was confirmed by NMR, MS and IR-spectroscopy.     

Calix[4]arene stabilized Transition Metal Imido Complexes

The usage of calix[n]arenes as ancillary poly(phenolate) ligands is a rapidly developing area in coordination chemistry. This article focuses on the synthesis, structure and reactivity of calix[4]arene‐ and calix[4]arene ether‐stabilized imido complexes of group 4 — 6 transition metals as well as on the comparison of calix[4]arene dialkyl ethers in particular with other widely employed related ligand systems such as salenes, porphyrins and tetraazaannulenes. Contrary to these nitrogen containing systems, it is much easier to control the charge of the ligand system through the degree of alkylation of the calixarene's lower rim without a major change in the geometry of the resulting metal complex. This could lead to isoelectronic and structurally closely related transition metal complex fragments for metals in neighboring groups of the periodic table or for metals in different oxidation states. The “intrinsic” reactivity of metal imido linkages might therefore be explored using calix[4]arenes and calix[4]arene ethers and first results are summarized in this research report.     

Synthesis of Schiff Base Calix [4] arene Crowns

This letter reports the synthesis of Schiff base calix [4] arene crowns containing m-xylylene phenol subunit, in which calix [4] arene Schiff base crowns 2a,2b and 2c were formed by 1:1 condensation of calix [4] arene diamine 1 with dialdehydes (2,6-diformyl-4-chlorophenol 3a,2,6-diformyl-4-methylphenol 3b,2,6-diformyl-4-tert-butylphenol 3c)under high dilute condition in refluxing anhydrous ethanol in 65-70% yield.     

四对-乙酰胺苯磺酰氧基杯[4]芳烃的合成

以对叔丁基苯酚为起始原料,通过缩合、取代反应合成了25,26,27,28-四对-乙酰胺苯磺酰氧基对叔丁基杯[4]芳烃,其结构经FT—IR,^1H NMR和FAB-MS表征。