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1.
The selectivity of inclusion ofp-xylene andp-dibromobenzene from their liquid mixtures by the host [Ni(NCS)2(4-methylpyridine)4] and the enthalpy of clathration were determined.p-Dibromobenzene is clathrated significantly more thanp-xylene. The heats of clathration show a linear dependence upon the composition of the enclathrated mixture and are considered to be indicative of the conclusion that the guest-guest interactions are negligible from the thermochëmical point of view. By comparing data presented herein with some literature data on competitive clathration an attempt to derive the entropy of guest exchange in the clathrate was performed.Presented at the International Seminar on Inclusion Compounds, Jaszowiec, Poland, 24–26 September, 1987.  相似文献   

2.
The synthesis and crystal structures of a calix[4]arene (1) with two affixed pyrene units and its corresponding inclusion compound with chloroform (1a) are reported. In both cases, stacking structures resulting from the influencing control of the pyrene units are observed. The occurrence of infinite or dimeric stack motifs of the pyrene units is dependent on the absence or presence of the included guest solvent.

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3.
The conditions for the formation of heteroleptic complexes of a lanthanide(iii) ion (Ln = La, Gd, and Tb) with p-sulfonatothiacalix[4]arene and a heteroaromatic chromophore in water were found using X-ray diffraction analysis, pH-metry, 1H NMR and UV—Vis spectroscopy, and nuclear magnetic relaxation. In the resulting complexes, the heteroaromatic chromophore is in the calix[4]arene cavity and the lanthanide ion is coordinated by the electron-donating groups of the upper or lower calix[4]arene rim. Emission spectroscopic studies revealed changed emission properties of TbIII ions in the terbium(iii)—p-sulfonatothiacalix[4]arene—bipy complex. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1871–1878, September, 2008.  相似文献   

4.
A cyclic pentamer was obtained fromp-(1,1,3,3-tetramethylbutyl) phenol. It crystallizes from a mixture of acetone and toluene at room temperature giving a 1 : 1 complex with toluene (compound A), whereas at 50°C the empty form (compound B) is obtained. Crystals of A are orthorhombic, space groupPna21,a = 20.083(2),b = 12.936(6),c = 28,423(1) Å,Z = 4, finalR value = 0.067. The empty form, B, is monoclinicP21/c,a = 18.695(2),b = 11.673(5),c = 35.100(4) Å, = 114.33(1),Z = 4, finalR value = 0.135. The macrocycle is in the cone conformation for both compounds; the toluene molecule lies in the cone as often found for calix[4]arenes.  相似文献   

5.
The stability constants (log K), the reaction enthalpy( H) and entropy ( S) of the complexesformed between some amino acids (glycine, L-alanine,L-valine, L-leucine, L-phenylalanine, L-tryptophan,L-threonine, and L-lysine) and peptides (glycyl-glycine,glycyl-L-alanine, glycyl-L-leucine, glycyl-L-phenylalanine,L-leucyl-glycine, L-leucyl-L-alanine, glycyl-L-valine,L-leucyl-glycyl-glycine, and glycyl-glycyl-glycine) withp-sulfonatocalix[4]arene and hexasodiump-sulfonatocalix[6]arene in aqueous solutions by meansof calorimetric titration have been investigated. The reportedresults demonstrate that the amino acids and peptides under studyform complexes with both p-sulfonatocalix[4]areneand hexasodium p-sulfonatocalix[6]arene. In the case of theamino acids and peptides the complexation with water-solublecalixarenes in aqueous solution is favored by enthalpiccontributions and disfavored by entropic contributions. However,no influence of the ring size of the calixarenes upon thecomplexation is observed. By comparison with the reaction ofthe sodium salt of phenol-4-sulfonic acid with amino acids amacrocyclic effect in case of the calixarenes is possible.  相似文献   

6.
In this paper we report evidence for an inclusion complex between carbon dioxide and p-t-butylcalix[4]arene. The complex was studied with infrared spectroscopy,single-crystal X-ray diffraction, solid-state NMR, and thermogravimetric analysis.Results indicate that 70% of the p-t-butylcalix[4]arene cavities could be occupiedby a CO2 molecule following exposure at 30 MPa and 40 °C.  相似文献   

7.
The non-symmetrical cobalt (III) complex cis-[Co(Ad)(en)2Cl]Cl (1Cl), possessing two flexible ethylendiaminate chelate rings (en) and monodentate N(9)-bound adeninate (Ad-) was chosen as the guest of p-sulfonatothiacalix[4]arene (STCA) to study the inclusion complex formation at wide range of pH 2–10. It was shown by 1H, NOE NMR methods and pH-metric procedure, that pH-driven variation of the inclusion mode of 1 + into calixarene cavity is the result of the protonation of 1 + via adeninate moiety.  相似文献   

8.
Calix[4]arene derivatives bearing anionic carboxylato groups at the upper rim (p-carboxylatocalix[4]arenes) are able to ‘grab’ paraquat dicationic guest through an induced-fit mechanism, which originates from the conformational mobility of calixarene skeleton.  相似文献   

9.
Calix[4]arenes with substituents at three of the four OH groups of the lower rim have been synthesized to investigate their properties as ionophores for Na+ and K+ metal ions. Crystal structures of these trisubstituted compounds revealed that the calixarene moiety has adopted a partial cone conformation, however the precise shape of the molecule, and intra- and intermolecular interactions, are significantly different due to variations of the substituents. Compound L2 encapsulated an acetonitrile molecule in the cavity of the calix moiety, held by C–H?π interactions. In the case of L3, the 2-(2-chloroethoxy)-ethanol substituent is involved in strong intramolecular C–H?π interactions with the centroid of the phenyl rings of the calix, bringing the 2-(2-chloroethoxy)-ethanol moiety inward the calix cone, which prevented the entry of any solvent molecule into the cavity. The complexation properties of L2L4 with Na+ and K+ ions have been investigated in chloroform–methanol mixture by 1H NMR and an attempt has been made to isolate these complexes in the solid state. Complexation studies reveal that only L3 forms a complex selectively with K+, involving 2-(2-chloroethoxy)-ethanol as a coordinating moiety. The association constant (1.4 × 105 M−1) of the complex has also been determined.  相似文献   

10.
The structures of three arene-tricarbonylchromium complexes prepared from cone and 1,3-alternate-25, 26,27,28-tetrapropoxycalix[4]arene(1) and Cr(CO)6 were determined by single crystal X-ray studies. Crystal data for 1,3-alternate-Cr(CO)3 are space groupP21/a,a=19.496(3)Å,b=11.118(2)Å,c=19.121(2)Å, =109.95°(1) andV=3895Å3. The structure was refined toRw=0.068. Crystal data for cone-Cr(CO)3 are space groupP21/a,a=21.457(4)Å,b=12.184(1)Å,c=14.816(2)Å, =91.61°(1) andV=3872Å3. The structure was refined toRw=0.077. Crystal data for cone-2Cr(CO)3 are space groupP21/a,a=18.019(3)Å,b=41.347(4)Å,c=11.743(2)Å, =97.39°(1) andV=8676Å3. The single crystal included two similar but slightly different structures but the data were successfully refined toRw=0.092. The structure of 1,3-alternate-Cr(CO)3 differs only slightly from that of the regular 1,3-alternate calix[4]arene. In contrast, cone-Cr(CO)3 and cone-2Cr(CO)3 show an unusual conformation with a pair of faced gablelike roofs, which is considerbly distorted from the regular cone calix[4]arene. The origin of this distortion is discussed in combination with the spectral studies.This paper is dedicated to the commemorative issue of the 50th anniversary of calixarenes.  相似文献   

11.
报道了2-羰基丙酸(4-吡啶甲酰基)腙(H~2L)与碱土金属(Ca,Mg,Sr,Ba)四种配合物的合成,结构及热稳定性。同时,用X射线单晶衍射仪测定了Mg和Ba两种配合物的晶体结构,结构分析表明两种配合物均属单斜晶系,空间群均为P2~1/c。此外,还比较讨论了各配合物不同成键方式所对应的IR特征及热稳定性变化规律。  相似文献   

12.
合成了Co23tricmenClZnCl423tri=N2胺乙基13丙二胺cmen=12二胺基丙烷体系中的部分配合物异构体解析了其中两异构体的晶体结构。其中晶体属单斜晶系空间群P21/ca=1.02112nmb=0.92082nmc=1.95004nmβ=97.9074°V=1.81617nm3Dc=1.803g·cm-3Z=4F000=1000.00μMoKα=29.66cm-1R=0.0317Rw=0.0923晶胞中含4个配合物阳离子4个ZnCl42-阴离子晶体属三斜晶系空间群a=0.9095318nmb=0.96942nmc=1.17712nmα=110.6694°β=92.2384°γ=91.2114°V=0.96973nm3Dc=1.750g·cm-3Z=2F000=520.00μMoKα=27.84cm-1R=0.0365Rw=0.0975晶胞中含2个配合物阳离子2个ZnCl42-阴离子及2个水分子。两异构体中Co3 为六配位其差异仅表现在二元胺cmen中甲基的取向不同。在结构单元中对映体的比例为1∶1。  相似文献   

13.
Synthesis and Crystal Structures of (PPh4)2[As2Se4Cl12] and (PPh4)2[As2Se4Br12] The reaction of PPh4Cl and As2Se3 with SOCl2 or with chlorine in dichloromethane affords (PPh4)2[As2Se4Cl12] with good yields. From PPh4Br, As2Se3 and bromine the corresponding bromo compound was obtained. According to the X-ray crystal structure determinations both compounds are isotypic, crystallizing in the space group of P1 . In the anions two Se2X2 molecules are linked with two X? ions forming an Se4X2 ring in chair conformation. Each X?-ion is associated with an additional AsX3 molecule (X = Cl, Br).  相似文献   

14.
用过氧化物法合成了 [Co(3,3-tri)(amp)Cl][ZnCl4]的两个经式异构体,晶体结构解析表明两者互为差向异构体。其中反式异构体 (仲氢相对于 Cl)晶体属单斜晶系,空间群 C2/c, a=2.7663(7)nm, b=0.9505(1)nm, c=1.8288(4)nm,β =105.57(2)°, V=4.632(1)nm3, Dc=1.706g· cm-3, Z=8, F000=2432.00,μ (MoKα )=23.51cm-1, R=0.033, Rw=0.041;顺式异构体 (仲氢相对于 Cl)晶体属三斜晶系,空间群, a=1.0790(2)nm, b=1.1749(1)nm, c=0.8920(1)nm,α =90.73(1)°,β =109.573(9)°,γ =80.60(1)°, V=1.0500(2)nm3, Dc=1.71g· cm-3, Z=2, F000=548.00,μ (MoKα )=25.73cm-1, R=0.022, Rw=0.030。两异构体中 Co3+为六配位,其差异仅表现在 3,3-tri仲胺上氢的取向不同。  相似文献   

15.
以[(bpca)Fe(CN)3]-(bpca=二(2-吡啶羰基)酰胺阴离子)为构筑基元,设计合成了2个新颖的3d-4f异金属配合物,{[(bpca)Fe(CN)3Pr(H2O)5]Cl2}n(1)和{[(bpca)2Fe2(CN)6Pr(H2O)6]Cl·4H2O}n(2),并测定了它们的晶体结构.化合物1的晶体属正交晶系,Pnma空间群;而化合物2属三斜晶系,P1空间群.在这2个化合物中,[(bpca)Fe(CN)3]-和[Pr(H2O)x]3 (1,x=5;2,x=6)交替排列形成一维链状结构,并通过π-π堆积作用、氢键作用及分子间短距离相互作用形成三维网络结构.  相似文献   

16.
From the reaction ofp-t-butylcalix[4]arene with -chloro-N,N-diethyl acetamide a new lipophilic ether-amide ligand (2) has been obtained in high yield. Solution studies show (2) to be a very strong cation receptor for alkali cations, especially sodium and potassium. The X-ray crystal structure determination of the free ligand (2) and two potassium complexes (KI and KSCN) shows the calix[4]arene in a fixed cone structure and the cation completely encapsulated in a polar cavity of eight oxygen atoms. Supplementary Data relating to this article are deposited with the British Library as supplementary publication No. SUP 82059 (57 pages).Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986.  相似文献   

17.
Thiacalix[4]arenes bearing two or four carboxylic functions on the lower rim served as starting compounds for the synthesis of novel calixarene oligomers connected by amidic functions. The cone conformers react smoothly with four molecules of 5-amino-calix[4]arene to yield the corresponding pentakis-calixarenes. On the other hand, because steric hindrance, the 1,3-alternate condenses only with two molecules leading thus to tris-calixarene, possessing a novel type of inherent chirality based on the 25,26-substitution pattern. The title compounds, which connect together ‘classical’ calixarene and thiacalixarene building blocks, represent a first step towards calixarene-based dendritic structures.  相似文献   

18.
The thermal deamination of [Co(diox·H)2(amine)2]X type complexes were studied in dynamic temperature conditions (diox·H2 stands for 1,2-cycloheptanedione dioxime (heptoxime, heptox·H2) and 1,2-cyclo-octanedione dioxime (octoxime, octox·H2), amine for aniline and pyridine,X for Br, I and NCS). Kinetic parametersn, E and logZ have been derived for some derivatives by means of two computerized integral methods. The influence of the sample weight, heating rate and chemical constitution upon the kinetic parameters, as well as the kinetic compensation effect are discussed.
Thermische Desaminierung einiger Komplexe des Typs [Co(Diox·H) 2 (Amin2]X. Über -Dioximinkomplexe der Übergangsmetalle, LXIV.
Zusammenfassung Die thermische Desaminierung einiger Komplexe des Typs [Co (Diox·H)2(Amin)2]X wurde bei dynamischen Temperaturbedingungen untersucht [Diox·H2 bedeutet 1,2-Cycloheptandiondioxim, (Heptoxim, Heptox·H2) und 1,2-Cyclooctandiondioxim (Octoxim, Octox·H2), Amin bedeutet Anilin und Pyridin,X bedeutet Br, I, bzw. NCS]. Die kinetische Parametern, E und logZ wurden mit Hilfe von zwei computergeeigneten Integralmethoden bestimmt. Der Einfluß des Gewichtes der Proben, der Heizungsgeschwindigkeit und der chemischen Zusammensetzung auf die kinetischen Parameter, bzw. der kinetische Kompensationseffekt werden diskutiert.
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19.
The title compound was obtained as colourless transparent prismatic crystals (from acetone/methanol 1:1), space groupPa=16.647(2),b=16.447(2),c=14.269(3) Å, =108.56(3), =105.63(3), =87.23(3)°,Z=1,D calc=1.03 g cm–3. Refinement was carried out using 2863 reflections, withI>(I). The molecule, which lies on a center of symmetry, possesses a roughly ellipsoidal shape with two sets of four phenolic nuclei following a helical arrangement. The polyether chains of two adjacent phenolic units partially fill the intramolecular cavity. No guest molecules are present. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication SUP 82025 (22 pages).For part 11 see [1].  相似文献   

20.
The effect of the ion-pairing of Co(III) complexes with p-sulfonatothiacalix[4]arene (STCA) on Fe(II)–Co(III) electron transfer rate was evaluated from the analysis and comparison of kinetic data in double Co(III)–Fe(II) and triple Co(III)–Fe(II)—STCA systems at various concentration conditions. Complexes [Co(en)3]3+(1), [Co(en)2ox]+(2), [Co(dipy)3]3+ (3), [Co(His)2]+(4) and [Fe(CN)6]4− were chosen as Co(III) and Fe(II) compounds. The effect of STCA was found to correlate with the association mode. The outer-sphere association with STCA was found to exhibit the insignificant effect on Fe(II)–Co(III) electron transfer k et constants for complexes 3 and 4 with bulky and rigid chelate rings, while more sufficient inclusion of flexible ethylendiaminate rings of 1 and 2 into the cavity of STCA results in the unusual increase of k et.  相似文献   

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