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1.
Ond?ej Kundrát Marcela Tkadlecová Josef Cva?ka Pavel Lhoták 《Tetrahedron letters》2007,48(38):6620-6623
Molecular tweezers based on calix[4]arene- or thiacalix[4]arene-porphyrin conjugates have been prepared starting from tetraformyl calixarenes and aminoporphyrin moieties. As proven by NMR and UV/vis titration experiments, these compounds form 1:1 complexes with C60 and C70 fullerenes in solution while possessing a high selectivity towards fullerene C70. 相似文献
2.
Ampoule reactions of C70 with n- and i-C3F7I were carried out at 250-310 °C. Two step HPLC separations allowed the isolation of several C70(n-C3F7)4-8 and C70(i-C3F7)4 compounds. Crystal and molecular structures of C70(n-C3F7)8-V, C70(n-C3F7)6O, C70(n-C3F7)4, and three isomers of C70(i-C3F7)4 have been determined by X-ray crystallography using synchrotron radiation. Molecular structures of the new compounds were compared with the known examples and discussed in terms of addition patterns and relative energies of their formation. 相似文献
3.
Hiroshi Imahori Atsushi Fujimoto Hiroki Hotta Tomokazu Umeyama Seiji Isoda 《Tetrahedron》2006,62(9):1955-1966
Structure and photoelectrochemical properties of nanostructured SnO2 electrodes deposited electrophoretically with the composite clusters of porphyrin-modified gold nanoparticle with a long, flexible spacer and C60 molecules have been examined to obtain basic information on the development of organic solar cells with a high performance. The photoelectrochemical system with the long, flexible spacer between the porphyrin and the gold nanoparticle in the porphyrin-modified gold nanoparticle exhibited comparable external quantum yield in the UV-vis regions relative to porphyrin-modified gold nanoparticle with a relatively short spacer—C60 composite reference system. These results demonstrate that a suitable spacer to incorporate C60 molecules efficiently between the porphyrins in porphyrin-modified gold nanoparticles is a prerequisite for improving the performance of porphyrin and fullerene-based organic solar cells. 相似文献
4.
Jerry L. Atwood Leonard J. Barbour Colin L. Raston Ida B. N. Sudria 《Angewandte Chemie (International ed. in English)》1998,37(7):981-983
Isostructural species are found in the solid state for the supramolecular 1:2 complexes of a calix[6]arene molecule and either C60 or C70 (see the structure of the [(calix[6]arene)(C60)2] complex on the right). The calixarene assumes a double-cone conformation, and the overall structure is a result of the complementarity of the building blocks with respect to size and form—in other words, the shallow calixarene cavity and the fullerene surface have similar curvatures. 相似文献
5.
C60 reacts thermally with 1,3-dipoles, formed in situ, from sulfide-bearing imines of glycine esters, and affords dihydro-pyrrolo [60]fullerene derivatives containing a vinylic sulfide group, which were isolated in good yields, and characterized with 1H and 13C NMR, FTIR, UV-vis spectroscopies, and with FAB, ESI mass spectrometries. The new derivatives contain a sulfide, an imine, and an ester functionality for further chemical transformations. Mechanistic considerations with regard to the loss of a mercaptan molecule in the course of the cycloaddition are deployed. 相似文献
6.
One isomer of C60(i-C3F7)8, three isomers of C60(i-C3F7)6, and the first mixed perfluoroalkylated fullerene, C60(CF3)2(i-C3F7)2, have been isolated by HPLC from a mixture prepared by reaction of C60 with heptafluoroisopropyl iodide in a glass ampoule at 260-290 °C. The molecular structures of the four new compounds have been determined by means of X-ray single crystal diffraction partially also by use of synchrotron radiation. Theoretical calculations at the DFT level of theory have been employed to rationalize the energetics of isomers and of C60-Rf binding. 相似文献
7.
Bo-Cheng Wang Likey Chen Kuei-Jen Lee Chang-Yuan Cheng 《Journal of Molecular Structure》1999,469(1-3):127-134
The spectral analysis indicates that all isomers of C60O, C70O and C60O2 have an epoxide-like structure (an oxygen atom bridging across a C–C bond). According to the geometrical structure analysis, there are two isomers of fullerene monoxide C60O (the 5,6 bond and the 6,6 bond), eight isomers of fullerene monoxide C70O and eight isomers of fullerene dioxide C60O2. In order to simulate the real reaction conditions at 300 K, the calculation of the different isomers of C60O, C60O2 and C70O fullerene oxides was carried out using the semiempirical molecular dynamics method with two different approaches: (a) consideration of the geometries and thermodynamic stabilities, and (b) consideration of the ozonolysis mechanism. According to the semiempirical molecular dynamic calculation analysis, the probable product of this ozonolysis reaction is C60O with oxygen bridging over the 6–6 bond (C2v). The most probable product in this reaction contains oxygen bridging across in the upper part of C70 (6–6 bond in C70O-2 or C70O-4) an epoxide-like structure. C60O2-1, C60O2-3 and C60O2-5 are the most probable products for the fullerene dioxides. All of these reaction products are consistent with the experimental results. It is confirmed that the calculation results with the semiempirical molecular dynamics method are close to the experimental work. The semiempirical molecular dynamics method can offer both the reaction temperature effect by molecular dynamics and electronic structure, dipole moment by quantum chemistry calculation. 相似文献
8.
(C70)2-
-tert-butylcalix[6]arene complex films on GC electrode surface showed two couples of redox reactions in mixed solvent of (1:1, v:v) acetonitrile and water containing tetra-butylammonium perchlorate. The electrocatalytic reduction for nitrite by these films was observed, indicating that (C70)2-
-tert-butylcalix[6]arene is capable of mediating the electron transfer to nitrite. 相似文献
9.
A novel open-cage C60 derivative (a 19-membered ring orifice), prepared by the sequential cage scission reactions of the ketolactam derivative of C60 with o-phenylenediamine, allows the encapsulation of one water molecule. The resulting endohedral water complexes were confirmed for the first time by mass spectroscopy. The efficiency of the encapsulation was affected by the substituent on the nitrogen atom. 相似文献
10.
Van Rossom W Caers J Robeyns K Van Meervelt L Maes W Dehaen W 《The Journal of organic chemistry》2012,77(6):2791-2797
In pursuit of highly preorganized macrocyclic host molecules for the complexation of anions, a series of oxacalix[2]arene[2]pyrimidine-based bis(thio)ureido receptors were synthesized and fully characterized. The pincer-like 1,3-alternate conformation of the oxacalix[4]arene scaffold, essential for an efficient host-guest interaction, was visualized by single-crystal X-ray analysis and supported by variable-temperature NMR studies. The anion binding properties of the receptors were evaluated via (1)H NMR titration experiments, showing intermolecular interactions with H(2)PO(4)(-), AcO(-), BzO(-), and Cl(-) ions. The host molecule bearing 4-nitrophenyl substituents on the bisurea binding pocket showed association constants in the range of 200-400 M(-1) in the strongly competitive solvent mixture of DMSO/0.5% H(2)O. 相似文献
11.
Fredrik LakeChristian Linde 《Tetrahedron letters》2012,53(30):3927-3929
A high yielding gram-scale synthesis of [13C4] N-benzylpiperazine for use as a convenient and versatile building block in isotope labeling studies of clinical drug candidates is reported. 相似文献
12.
13.
D. P. Domonov S. I. Pechenyuk N. L. Mikhailova A. T. Belyaevskii 《Russian Journal of Inorganic Chemistry》2007,52(7):1027-1032
The thermolysis of the complexes [Co(NH3)6]2C2O4[Cu(C2O4)2]2 (I) and [Co(NH3)6]Cl[Cu(C7H4O3)2] (II) in air and hydrogen at 200, 350, and 500°C and the composition and properties of the thermolysis products are considered.
The oxidative thermolysis of the complexes yields mixtures of cobalt and copper oxides, including mixed ones. The reductive
thermolysis of the complexes yields a Co + Cu bimetallic powder in the case of compound I and a Co + Cu + C powder in the
case of compound II. The thermal behavior of the complexes is governed by the nature of the ligand coordinated to the copper
atom. The observed data are explicable in terms of the properties of this ligand. The chemistry of the oxidative and reductive
thermolysis is discussed.
Original Russian Text ? D.P. Domonov, S.I. Pechenyuk, N.L. Mikhailova, A.T. Belyaevskii, 2007, published in Zhurnal Neorganicheskoi
Khimii, 2007, Vol. 52, No. 7, pp. 1104–1110. 相似文献
14.
Karine Gorgy Marie-Noëlle Collomb Jean-Claude Leprêtre Alain Deronzier Carole Duboc-Toia Stphane Mnage Marc Fontecave 《Electrochemistry communications》2001,3(12)
A simple electrochemical procedure to tailor thin polymeric films containing the [FeII(bpy)2(CH3CN)2]2+ and/or [FeII(bpy)3]2+-like cores have been described (bpy=2,2′-bipyridine). The procedure is based on the electroreductive precipitation of soluble polymers prepared in situ in CH3CN by mixing Fe3+ ions and a bis bipyridyl ligand, (chiragen: chir). In the resulting [FeII(chir)(CH3CN)2]n2+ films, the two labile S ligands can be easily replaced by a bidentate ligand. This method has been applied with success to design a modified electrode with a supramolecular structure. 相似文献
15.
Lemi Türker 《Journal of Molecular Structure》2004,680(1-3):47-51
Semiempirical quantum chemical calculations at the level of AM1 (restricted Hartree–Fock) have been performed on a fullerene derivative, C54N4, theoretically obtained from C60 and its mono and diprotonated forms. All these structures are stable, but endothermic in nature. Some calculated geometrical and physicochemical properties of these have also been reported. 相似文献
16.
Qianling Guo Wenxiang Zhu Shujing Dong Shulan Ma Xi Yan 《Journal of Molecular Structure》2003,650(1-3):159-164
The title calixarene, dimanganese thiacalix[4]arene tetrasulfonate, was prepared and its crystal structure was determined. [Mn(H2O)6]2[thiacalix[4]arene tetrasulfonate]·0.5H2O crystallizes in the monoclinic system, P2(1)/m space group, with a=13.014 (6), b=14.146 (9), c=13.184 (7) Å, β=113.307 (10)°, V=2229 (2) Å3 and Dc=1.710 gcm−3, Z=2. The title calixarene exists in the solid state as bilayer structure. The hydrophobic organic layer consists of thiacalix[4]arene tetrasulfonate in an up-down fashion, whereas, the hydrophilic inorganic layer consists of hexaaquamanganese (II) which is linked to the former through a second-sphere coordination. 相似文献
17.
D. V. Konarev N. V. Drichko R. N. Lyubovskaya Yu. M. Shul''ga A. L. Litvinov V. N. Semkin Yu. A. Dubitsky A. Zaopo 《Journal of Molecular Structure》2000,526(1-3):25-29
A molecular complex of fullerene C60 with triptycene, TPC·C60 is obtained. The complex has a three-dimensional packing of C60 molecules. According to the IR spectra, the freezing of free rotation of C60 molecules in the complex is maintained up to 360 K. The XP-spectra of TPC·C60 show the suppression of π–π* transitions of TPC phenylene rings. The separation of C60 molecules by TPC ones in TPC·C60 results in low intensity of the C60 transitions in the 420–500 nm range in an optical spectrum. This absorption is assumed as that attributed to intermolecular transitions between adjacent C60 molecules. 相似文献
18.
N.S. Chilingarov A.V. NikitinJ.V. Rau I.V. GolyshevskyA.V. Kepman F.M. SpiridonovL.N. Sidorov 《Journal of fluorine chemistry》2002,113(2):219-226
Fluorination of C60(s), C60(s)-MnF2(s), C60(s)-NiF2(s) and C60(s)-MnF3(s) mixtures has been studied by Knudsen cell mass spectrometry with admission of molecular fluorine. The fluorination is selective when fullerene reacts with the fluorine chemisorbed on the MnF2 surface. When the MnF2 content in the initial mixture is at least 90 mol% both C60F18 and C60F36 are selectively formed. Under certain conditions, mixtures predominantly containing one of three compounds C60F38, C60F40, and C60F42 can be obtained. A consecutive change of the main fluorination products (C60F18 and C60F36) takes place at constant temperature (720 K) and on fluorine admission. A quantitative explanation of this fact is given. Selective fluorination of C60(s) by molecular fluorine is compared with solid-phase fluorination using MnF3(s) as a fluorinating agent. 相似文献
19.
Bambar Davaasuren 《Journal of solid state chemistry》2009,182(6):1331-5692
The lanthanum iron carbide La3.67[Fe(C2)3] was prepared from the elements by argon arc-melting followed by annealing. The crystal structure of the ternary phase was reported previously (space group P63/m with a=878.7(2) pm, and c=535.1(1) pm) [A.M. Witte, W. Jeitschko, Z. Naturforsch. 51b (1996) 249-255]. In the present work the compound was reinvestigated by X-ray powder and single crystal diffraction, and was further characterized by metallographic methods and chemical analyses. Our diffraction data clearly reveal a superstructure with weak superstructure reflections in the space group P63/m with a=879.26(8) pm and c=1604.59(15) pm, thus tripling the previously reported subcell. The crystal structure (refinement to R1=0.044 and wR2=0.075 for 1387 unique reflections and 60 variables) contains Fe(C2)3 trigonal planar groups with the C2 ligands bonded end-on to the Fe atoms. The C-C distance is typical for a double bond. La atoms as the least electronegative component surround the complex anions and form a framework of face-sharing tricapped trigonal prisms. The resulting hexagonal channels at 0, 0, z of the partial structure with chemical composition La3FeC6 are occupied by four additional La atoms per unit cell. These La atoms are fully ordered within a linear chain and display a Peierls-like distortion pattern. However, no long-range order in the a−b plane has been observed due to the random orientation of the chains. Because of the two different orientations which are possible for each chain the situation is similar to an Ising model on a triangular lattice. 相似文献
20.
The article depicts a detailed study regarding copper selective chemosensing and complexation nature of 5,11,17,23-tetrakis[(N,N-diphenylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (PAC4). Its photophysical characteristics in various solvents of different polarities along with the influence of acid and base on its spectral properties in these solvents are also discussed. The complexation affinity of PAC4 with regard to its latent applications as Cu(II) selective colorimetric and fluorescent sensor among the selected series of various cations such as Li(I), Na(I), K(I), Rb(I), Ba(II), Sr(II), Al(III), Fe(III), Cd(II), Co(II), Hg(II), Mn(II), Ni(II), Pb(II) and Zn(II) was examined by UV–visible and fluorescence emission spectroscopy in dichloromethane:acetonitrile (DCM:MeCN) solvent system. In addition, the process of complexation has been investigated through Job's plot and it has been observed that the complex between PAC4 and Cu(II) is formed in 1:1 stoichiometric ratio. The complex formation between PAC4 and Cu(II) has also been confirmed by FT-IR spectroscopy and thermal gravimetric analysis (TGA). 相似文献