Synthesis and nitration of calix[4] (aza)crowns

Calix[4] (aza) crowns containing amide groups 3a-d were synthesized by the reactions of calix[4]arene (1a) or p-tert-butylcalix[4]arene (1b) with N, N'-ethylenebis(2-chloroac-etamide) (2a) or N, N'-1,2-phenylenebis(2-chloroacetamide) (2b) by one step procedure in yields of 85-90% . Calix[4]-(aza) crowns 4a-b could be obtained by the reduction of 3a-b with LiAlH4 in yields of 51 and 67% , respectively. The nitration of 3a or 3c afforded new chromogenic calix[4]arenes 5a bearing two nitrophenol moieties and 5c bearing one nitro-phenol and one quinone moiety, respectively. The ipso-nitrations of 3b and 3d were also studied. Both gave the products containing one nitrophenol and one quinone moiety. Moreover, a very interesting calix[4]arene derivative 5d containing one cyclohexadienone moiety was also separated as the main product when 3d was ipso -nitrated.     

Nano CaCO3:An Unique Condensation Agent for the Preparation of Monosubstituted Calix[4] arene by Ring-opening Reaction

Nano CaCO3 was used as a condensation agent in the ring-opening reaction of p-tert-butylcalix[4] arene with epichlorohydrin to afford 5,11,17,23-tetra-tert-butyl1-26,27,28-trihydroxy-25-(1′-chloro-2′-hydroxy-3′-propyl)calix(4] arene regioselectively in 52% yield,The yield was less than 2% by using normal CaCO3 instead of nano one under the same conditions.     

QCM 表面自组装胱氨酸1，3－桥连杯[4]芳烃膜用于识别气相丁胺

Two cystine-bearing 1,3-bridged calix[4]arenes were used as the coatings of the quartz crystal microbalance (QCM) with gold electrodes. The two calix[4]arene derivatives were self-assembled onto the gold electrode surface by the covalent attachment between the di-sulfur and gold. The compound of cystine-bearing bi-phenylalanine 1,3-bridged calix[4]arene (CPC) with longer alkyl chain had better self-assembled capacity onto the fresh surfaces of gold electrode than that of cystine-bearing 1,3-bridged calix[4]arene (CC) with comparably shorter alkyl chain.The modified QCM sensors were used to recognize the butylamine isomers in gas. The results showed that the QCM coated with both compounds had preferential affinity to n-butylamine, then i-butylamine, t-butylamine in the range of low concentrations, indicating that in the recognition process, the steric hindrance effect played an important role when forming complex with guest molecules. When the concentrations of the analytes were increased, the polarity and the magnetism of the butylamine became determinative factors. The reversibility was improved greatly and the equilibrium time was much shorter on the self-assembled film than on the film obtained by dropping coating.     

Studies on Properties of p—Nitrophenylazo Calix[4]arene Derivatives

The p-nitrophenylazo calix[4] arene derivatives la-ld with nonlinear optical(NLO)properties were prepared by the diazo-coupling reaction of calix[4]arene with p-nitrophenyl diazonium.The diazotization reaction of p-nltroaniline was caried out with isoamyl nitrite as a source of nitrous acid in EtONa/EtOH under refluxing conditon.X-Ray crystallographic analysis and ^1H NMR sptectra reveal that they exist as cone conformation in crystal state or in soution.HRS measurements at 1064 nm in THF indicate that p-nitrophenylazo calix[4]arenes have higher hyperpolarizability βz values than the corresponding reference compound 4-(4-nitrophenylazo)-2,6-dimethyl-phenol,without red shift of the charge transfer band.The tetrakis p-nitropheylazo calix[4]arene(2)with longer alkyl chains can form monolayer aht the air/water interface.     

High extraction ability of 1,3-dialkynyl calixarene towards mercury（Ⅱ） ion

The reaction of 1,3-dipropyn-2-yloxycalix[4]arene with mercury(II)acetate could give mercury-containing alkynyl calixarenepolymer.The extraction behavior of 1,3-dipropyn-2-yl-oxycalix[4]arene towards mercury(II)ion was examined.When the moleratio of Hg~(2 )/calixarene was 1:1,the extractive percent can reach to 99.1%,and the extraction capacity was up to 431 mg/g.It couldalso decrease the Hg~(2 )concentration from 5 to 0.85 mg/L,which was only 17%of the national standard of effluent and satisfied thenational standard of drinking water.The extraction process included chemical reaction.     

一对含有苯甲醛基修饰的杯芳烃异构体的晶体结构以及它们与铽离子配位的光物理性质

Two calix[4]arene isomers with benzaldehyde moieties, i.e., 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(o-formyl-phenoxy)ethoxy]-26,28-dihydroxycalix[4]arene (3) and 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(p-formylphenoxy)-ethoxy]-26,28-dihydroxycalix[4]arene (4), were synthesized according to a newly designed route in high yields, and their crystal structures have been determined by X-ray crystallographic study. The photophysical behavior on complexation of calix[4]arene derivatives 3 and 4 with terbium(Ⅲ) nitrate was investigated in anhydrous acetonitrile at 25℃ by UV-Vis and fluorescence spectroscopies. The crystallographic structure of 3 indicated that the eight oxygen atoms formed a preorganized ionophoric cavity due to intramolecular π-π stacking, which could encapsulate lanthanide ions tightly. In sharp contrast, the compound 4 formed a linear array by intermolecular π-π stacking, hence the oxygen atoms of pendant arms could not coordinate with metal ions, giving a poor binding ability to Tb^3 . The absorption spectra of 3 with Tb^3 showed clearly a new broad intense absorption at 385nm. Interestingly, the narrow emission line spectrum has also been observed for compound 3 with Tb^3 , and the results obtained were discussed from the viewpoint of energy transfer mechanism between host structures and the properties of lanthanide ions.     

Study on Interaction of L-Tryptophan with p-Suffonatocalix[4]arene by Spectrofluorometry

The interactions between L-tryptophan（L-Trp） and water-soluble p-sulfonatocalix[4]- arene （SCX4） were investigated by spectrofluorometry. The effect of pH was discussed. The interaction process was estimated from the thermodynamic viewpoint. The SCX4 was found to be able to adjust its conformation to fit the size of L-Trp, and the benzene of L-Trp penetrated into the hydrophobic cavity of SCX4. Meanwhile, the binding mechanism was further elucidated by IHNMR and molecular mechanics calculations.     

单氧代-二硒烷基-1, w-二氧取代杯[4]衍生物的合成,结构及萃取性能研究

Novel macrocyclic monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a were synthesized by the reaction of calix[4]arene dibromides 1-5 with the disodium salt of bis（2-selenylethyl）ether in the yields between 28% and 64%. Their structures were characterized by proton and carbon NMR spectra. X-Ray structure analysis of la further confirmed the cone conformation of compounds 1a-5a. An interesting host-guest complex of la with dichloromethane via CH/π and C1/π interactions was elucidated. Extraction experiments showed that these novel monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a had strong extraction ability towards mercury ion. The interaction of Hg^2＋with the calix ligand has also been investigated by 1^H NMR titration.     

Construction of [1]rotaxanes with pillar[5]arene as the wheel and terpyridine as the stopper

The condensation reaction ofω-aminoalkyleneamide-functionalized pillar[5]arenes with 2-(4-([2,2’:6’,2〃-terpyridin]-4’-yl)phenoxy)acetic acid or 4-(4-([2,2’:6’,2"-terpyridin]-4’-yl)phenoxy)butanoic acid in dry chloroform at room temperature under the catalysis of HOBT/EDCl resulted in novel pillar[5]arene diamido-bridged terpyridine derivatives.~1 H NMR and 2 D NOESY spectra clearly indicated that the interesting[1]rotaxanes were formed by longer alkylene such as propylene,butylene and hexylenediamido chains threading into the cavity of the pillar[5]arene and with larger terpyridine acting as the stopper.However,the shorter ethylenediamido chain only exists outer of cavity of pillar[5]arene and the molecule exist on free form.     

Unprecedented synthesis of chiral calix[4](aza)crowns and its potent encapsulating methanol

Unprecedented synthesis of chiral (aza)crown ethers of calix[4]arene derivatives bearing a carboxyl amide bridge was described. The synthesis proceeds through condensation of the corresponding dinitriles with optically active 1,2-aminoalcohols,and is catalyzed by the ZnCl2 Lewis acid at elevated temperature in a very efficient one-pot process. The cavity of calix[4](aza)crowns can encapsulate methanol molecules by O—H...π interaction,which has been confirmed by X-ray crystal structures and ESI-MS.     

含酰胺和席夫碱单元的杯[4]芳烃衍生物的合成与配合性能

杯[4]-1,3-二乙酸乙酯衍生物1与水合肼反应生成杯[4]芳烃酰肼衍生物2, 然后进一步与相应的芳醛反应, 高产率地合成了三个新型的含酰胺和席夫碱单元的杯[4]芳烃衍生物3a～3c和一例新型杯[4]冠醚4. 阳离子萃取实验表明新型杯芳烃衍生物比只含有酰胺基或席夫碱基的杯芳烃衍生物有更强的软金属离子配合性能, 杯[4]冠醚4还对Ag^＋有较好的选择性萃取能力.     

含席夫碱和酰胺单元的新型双杯[4]芳烃的合成

对叔丁基杯[4]芳烃-1,3-二醛基衍生物2与对叔丁基杯[4]-1,3-二酰肼衍生物4在稀释条件下进行“1＋1”分子间缩合反应, 高产率地合成了含席夫碱和酰胺单元的新型双杯[4]芳烃衍生物5. 所有新化合物的结构经元素分析、质谱、核磁共振谱等表征证实, 杯[4]芳烃单元均为1,3-桥联且采取锥式构象.     

High-performance Liquid Chromatography Study of the Nitration Course of Tetrabutoxycalix[4]arene at the Upper Rim:Determination of the Optimum Conditions for the Preparation of 5,11,17-Trinitro-25,26,27,28-tetrabutoxycalix[4]arene

A selective nitration of calix[4]arene at the upper rim in one pot process was described by monitoring the time dependence of the distribution of products by high‐performance liquid chromatography (HPLC). The discrimination of five nitrated products was accomplished by molecular symmetry considerations and ¹H NMR analysis. As a result, unusual 5,11,17‐trinitrocalix[4]arene ( 2d ) was obtained in 57% isolated yield. 5,11‐Dinitro‐calix[4]arene ( 2b ) and 5,11,17‐trinitrocalix[4]arene ( 2d ) with tetranitrocalix[4]arene 2e were further characterized by crystal X‐ray diffraction analysis. Furthermore, as an example of potential application, trinitrocalix[4]arene 2d could be converted to triaminocalix[4]arene 3d conveniently.     

含噻二唑官能基的对叔丁基硫桥杯[4]芳烃衍生物的合成及结构

以对叔丁基硫桥杯[4]芳烃(1)为原料, 在碳酸钾存在下与碘甲烷反应, 生成1,3-二取代桥杯[4]芳烃(2), 其分别与1,2-二溴乙烷, 1,3-二溴丙烷在碳酸钾的存在下进行烷基化反应, 生成硫桥杯[4]芳烃衍生物3和4. 在氢氧化钠存在下,其与过量的含不同官能团的2-巯基-1,3,4-噻二唑反应, 生成下缘含1,3,4-噻二唑基的硫桥杯[4]芳烃衍生物5a, 5b, 6a和6b, 并通过了¹H NMR, ¹³C NMR, IR, MS和元素分析的确证. 同时, X射线分析确定了硫桥杯[4]芳烃3和5a的晶体结构.     

苄连氮桥联双硫杂杯[4]芳烃的合成

硫杂杯[4]二醛基衍生物(1)在水合肼中肼解,合成了新化合物硫杂杯[4]二醛腙基衍生物(2);1和2在弱酸的催化下反应合成了新的具有对称结构的苄连氮双硫杂杯[4]芳烃(3);2和3的结构经1H NMR,IR,ESI-MS和元素分析表征.     

Synthesis and crystal structure of uranium(IV) complexes with calix[n]arenes (n = 4, 6 and 8): mononuclear, polynuclear and 1D polymeric species

Reactions of UCl4 with calix[n]arenes (n = 4, 6) in THF gave the mononuclear [UCl2(calix[4]arene - 2H)(THF)2].2THF (.2THF) and the bis-dinuclear [U2Cl2(calix[6]arene - 6H)(THF)3]2.6THF (.6THF) complexes, respectively, while the mono-, di- and trinuclear compounds [Hpy]2[UCl3(calix[4]arene - 3H)].py (.py), [Hpy](4)[U2Cl6(calix[6]arene - 6H)].3py (.3py), [Hpy]3[U2Cl5(calix[6]arene - 6H)(py)].py (.py) and [Hpy]6[U3Cl11(calix[8]arene - 7H)].3py (.3py) were obtained by treatment of UCl4 with calix[n]arenes (n = 4, 6, 8) in pyridine. The sodium salt of calix[8]arene reacted with UCl4 to give the pentanuclear complex [U{U2Cl3(calix[8]arene - 7H)(py)5}2].8py (.8py). Reaction of U(acac)4 (acac = MeCOCHCOMe) with calix[4]arene in pyridine afforded the mononuclear complex [U(acac)2(calix[4]arene - 2H)].4py (.4py) and its treatment with the sodium salt of calix[8]arene led to the formation of the 1D polymer [U2(acac)6(calix[8]arene - 6H)(py)4Na4]n. The sandwich complex [Hpy]2[U(calix[4]arene - 3H)2][OTf].4py (.4py) was obtained by treatment of U(OTf)4 (OTf = OSO2CF3) with calix[4]arene in pyridine. All the complexes have been characterized by X-ray diffraction analysis.     

苄连氮基桥联的双杯[4]芳烃的合成

对叔丁基杯[4]芳烃-1, 3-二醛基衍生物1分别与水杨醛腙、水合肼进行“1＋2”和“2＋2”缩合反应, 方便地合成了苄连氮基取代或桥联的新型杯[4]芳烃衍生物2和双杯[4]芳烃衍生物3, 产率分别为84%和81%. 新化合物的结构与构象经元素分析、质谱、核磁共振谱和1H-1H COSY谱图等表征证实, 双杯[4]芳烃衍生物3为空间结构完全对称的具有管状三维空腔的杯式构象.     

Synthesis and characterization of diametrically substituted tetra-O-n-butylcalix[4]arene ligands and their chelated complexes of titanium,molybdenum, and palladium

The ligation properties of three new upper-rim-substituted calix[4]arene ligands, 5,17-bis(hydroxymethyl)-tetra-n-butoxycalix[4]arene ((HOCH2)2-nBu4Clx, 7), 5,17-bis((diphenylphosphinito)methoxy)-tetra-n-butoxycalix[4]arene ((PPh2OCH2)2-nBu4Clx, 8), and 5,17-bis((diphenylphosphino)methyl)-tetra-n-butoxycalix[4]arene ((PPh2CH2)2-nBu4Clx, 10) are reported herein. The newly prepared compounds differ from previously reported diametrically substituted calix[4]arene derivatives in that the lower-rim substituent was n-butyl. The presence of this lower-rim substituent did not reduce the inherent crystallinity of these complexes as purification of all materials occurred via simple crystallizations. The key precursor for the syntheses of 8 and 10 was 7, acquisition of which occurred in six steps starting from tetra-tert-butylcalix[4]arene, 1. Calix[4]arene derivatives include, tetra-n-butoxycalix[4]arene (nBu4Clx, 3), 5,11,17,23-tetrabromo-tetra-n-butoxycalix[4]arene (Br4-nBu4Clx, 4), 5,17-dibromo-tetra-n-butoxycalix[4]arene (Br2-nBu4Clx, 5), 5,17-bis(formyl)-tetra-n-butoxycalix[4]arene ((CHO)2-nBu4Clx, 6), and 5,17-bis(chloromethyl)-tetra-n-butoxycalix[4]arene ((ClCH2)2-nBu4Clx, 9), all of which were synthesized using modifications of existing procedures. Characterization of all compounds occurred, when possible, using 1H, 13C, and 31P NMR, elemental analyses, FAB-MS, ESI-MS, FT-IR, and X-ray crystallography. The solid-state structures of all calix[4]arene intermediates and ligands showed that the annulus adopted the pinched-cone conformation in which the average C(5)...C(17) intraannular separation was 4.5 +/- 0.4 A. Reaction of 7 with CpTiMe3 yielded the cis-chelate, CpTi(Me)[(OCH2)2-nBu4Clx] (11), quantitatively. Data obtained using ESI-MS (positive-ion mode) confirmed the monomer formulation showed above, and 1H NMR spectra provided sufficient information to deduce the nature of the Ti coordination sphere. Reaction of 8 with cis-Cl2Pd(NCPh)2 in refluxing benzene afforded cis-Cl2Pd[(PPh2OCH2)2-nBu4Clx] (12) in good yields. The monomeric identity of this compound was verified by both X-ray crystallography and positive-ion ESI-MS. The cis-bidentate calix[4]arene ligand did not undergo any noticeable contortion upon chelation of the PdCl2 fragment. Acid-promoted decomposition of 12 occurred in the presence of adventitious HCl and gaseous HCl, and the products of this decomposition were 9 and [mu2-ClPd(PPh2OH)(PPh2O)]2. In addition, chelates of 8 that contained Mo(CO)3L (L = NCMe (14a), NCEt (14b), and CO (14c)) showed that the mode of coordination was relatively insensitive to the identity of the metal. X-ray crystallography afforded views of the solid-state structures of 14b,c and, like 12, showed that the Mo(CO)3L fragment resided above the pinched-cone of the calix[4]arene. 1H NMR revealed that C-H/pi interactions existed between L (14a,b) and a phenyl ring of the coordinated phosphinite. Finally, the bis(diphenylphosphine)calix[4]arene ligand (10) readily coordinated the Mo(CO)3L species, but the reaction did not go to completion, as evidenced by 1H NMR, even after a 5 day reaction time. Data suggest that the product is similar to that observed for 12 and 14, but the incomplete reaction complicated attempts to obtain pure material and prohibited definitive assignment of the coordination array.     

A Facile Method to Synthesize Spiro-calix[4]arenes

Calixarenes have absorbed considerable interests for their outstanding abilities of recognition for cations, anions and organic molecules1. In order to include larger and more complex molecules, polytopic receptors were designed from two or more host macrocycles linked by one or several links. Therefore, double-calixarenes and oligocalixarenes have been synthesized and reviewed2. Among these polytopic receptors, double-calixarenes can be used as the mimic of ion channel or to self-organize koi…     

Energies of charge transfer and supramolecular interactions of some mono O-substituted calix[6]arenes with [60]fullerene by absorption spectrometric method

Equilibria for the formation of supramolecular complexes of [60]fullerene with a series of mono O-substituted calix[6]arenes, namely: (i) 37-methoxy-38,39,40,41,42-pentahydroxy-5,11,17,23,29,35-hexa(4-tert-butyl)calix[6]arene (1), (ii) 37-allyl-38,39,40,41,42-pentahydroxy-5,11,17,23,29,35-hexa(4-tert-butyl)calix[6]arene (2), (iii) 37-phenacyl-38,39,40,41,42-pentahydroxy-5,11,17,23,29,35-hexa(4-tert-butyl)calix[6]arene (3), (iv) 37-ethylester-38,39,40,41,42-pentahydroxy-5,11,17,23,29,35-hexa(4-tert-butyl)calix[6]arene (4) and (v) 37-benzyl-38,39,40,41,42-pentahydroxy-5,11,17,23,29,35-hexa(4-tert-butyl)calix[6]arene (5) have been studied in CCl4 medium by absorption spectroscopic technique. The stoichiometry has been found to be 1:1 ([60]fullerene:calix[6]arene) in each case. An absorption band due to charge transfer (CT) transition is observed in each case in the visible region. The vertical ionisation potentials (I(D)(v)) of all the calix[6]arenes under study have been estimated utilising CT transition energy. The experimental I(D)(v) values also yield a good estimate of the electron affinity of [60]fullerene. The degrees of CT in the ground state of the complexes have been found to be very low (about 0.15%). Resonance energy of the complexes have been estimated. Thermodynamic parameters for the supramolecular complex formation of [60]fullerene with mono O-substituted calix[6]arene receptors are reported. It is observed that among the calix[6]arenes under the present study, only 1 and 4 form inclusion complexes with [60]fullerene. This has also been substantiated by theoretical calculation using PM3 method. Thus presence of one substituent group (of different types) on the lower rim of the calix[6]arene molecule has been shown to govern the host-guest complexation process.