157 resultados para FULLERENE DERIVATIVES


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Three new asymmetrical ruthenium (II) complexes: [Ru(phen)(2){phen-NHCO(CH2)(4)Br}](PF6)(2), [Ru(phen)(2){phen-NHCO(CH2)(5)Br}](PF6)(2) and [Ru(phen)(2){phen-NHCO(CH2)(10)Br}](PF6)(2) were synthesized, which were confirmed by the technique of FT-IR, H-1 NMR and ESI-MS. The electrochemical and fluorescent properties of three Ru (II) complexes were investigated with cyclic voltammetry and fluorometry.

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Four typical LB monolayer film materials, Ru(phen)(3)(2+) complexes with one ligand attached to different long chain alkyl amides, were designed and synthesized. Their chemical structures were identified by the techniques of FT-IR, H-1 NMR and ESI-MS. Also, UV-Vis, electrochemistry and fluorescence of these complexes are reported.

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The gas-phase ion-molecule reactions of C-60 with the methoxymethyl ion [CH3O=CH2](+) and the 1-hydroxyethyl ion [CH3CH=OH](+) generated under the self-chemical-ionization (self-CI) conditions of alkyl methyl ethers and primary alcohols were studied in the ion source of a mass spectrometer. The adduct ions [C60C2H5O](+) and protonated molecules [C60H](+) were observed as the major products of C-60 with the plasma of alkyl methyl ethers. On the contrary, the reactions of C-60 With the plasmas of primary alcohols produced few corresponding adduct ions. The AM1 semiempirical molecular orbital calculations were carried out on 14 possible structures. The calculated results showed that the most stable structure among the possible isomers of [C60C2H5O](+) is the [3+2] cycloadduct. According to experimental and theoretical results, the pathway for the formation of the adduct was presented.

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Four novel screw-like Ru(II) complexes, tris(5-lauramide-1,10-phenanthroline)Ru(II) bishexafluorophosphate, tris(5-myristamide-1,10-phenanthroline)Ru(II) bishexafluorophosphate, tris(5-palmitamide-1,10-phenanthroline)Ru(II) bishexafluorophosphate and tris (5-stearamide-1,10-phenanthroline)Ru(II) bishexafluorophosphate have been efficiently synthesized. They are confirmed by the techniques of IR, H-1 NMR, H-1-H-1 COSY and ES-MS. Also, their electrochemistry, fluorescence and electrochemiluminescence are reported.

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Distyryl benzene derivatives (DSB-1 and DSB-2) were deposited on a KBr (001) surface. DSB-1 molecules took two kinds of orientations depending on the substrate temperature. On the other hand, DSB-2 grew epitaxially. The longitudinal axes of DSB-2 molecules were oriented parallel to the substrate surface.

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New aromatic diamines [(1) and (2)] containing polycycloalkane structures between two benzene rings were synthesized by HCl-catalyzed condensation reaction of aniline hydrochloride and corresponding polycycloalkanone derivatives. The structures of diamines were identified by H-1-NMR, C-13-NMR, FTIR spectroscopy, and elemental analysis. The polyimides were synthesized from the obtained diamines with various aromatic dianhydrides by one-step polymerization in m-cresol. The inherent viscosities of the resulting polyimides were in the range of 0.34-1.02 dL/g. The polyimides showed good thermal stabilities and solubility. All the polymers were readily soluble in N-methyl-2-pyrrolidone, m-cresol, tetrachloroethane, etc. Some of them were soluble even in chloroform at room temperature. The glass transition temperatures were observed in the range of 323-363 degrees C, and all of the polymers were stable up to 400 degrees C under nitrogen atmosphere. (C) 1999 John Wiley & Sons, Inc.

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The infrared spect ra of N-n-(4-nitrophenyl)azophenyloxyalkyldiethanolamines (Cn) are examined in the range of 4000-400 cm(-1) at different temperatures and the assignment of the fundamental vibrations given. Based on (1) the localization of the broad absorption band at 3456 cm(-1), and (2) attribution of the associated OH bands centred at 1410-1390, 1100, and 650-634 cm(-1) to, respectively delta OH deformation, nu C-O stretching and gamma OH out-of-plane bending, intermolecular hydrogen bonding between OH groups in the crystalline, liquid crystalline and isotropic states is proposed. By considering the results of FTIR, WAXD and DSC measurements, the molecular arrangement of C10 in its smectic A phase as consisting of hydrogen bonding and strong interaction between dipolar groups (NO,) is proposed. This may explain the high stability and high orientational ordering property of Cn compounds in the liquid crystalline state compared with that of n-bromo-1-[4-(4-nitrophenyl)azophenyl]oxyalkanes (Bn).

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Self-assembled monolayers(SAMs) of trichlorogermanyl propanoic acid derivatives on hydroxylated silicon substrates are prepared for the first time. Contact angle measurement, ellipsometry and X-ray photoelectron spectrometry(XPS) are used to characterize these SAMs, It is demonstrated that a quasi-2D network is formed on the surface of the substrate after molecules adsorbed on it. The molecular chains have certain tilt angles to the substrate surface, The wettabilities of the SAMs are various,because the molecules adsorbed and liquids used in the experiments are different. It can be concluded that trichlorogermanes have similar self-assembly behavior as trichlorosilanes, Four SAMs are studied together: they are acid, ethyl, butyl and hexyl surfaces whose results are of good consistency.

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Molecular connectivity index and comparative molecular field analysis (CoMFA) have been applied to the studies of the correlation of the derivatives of benzamide and their antiallergic activities. The results achieved by using CoMFA based on 3D factors are much better than that obtained by using multiple regression analysis based on majorly 2D structural information. The CoMFA results show that the dominant factor which affects activity is steric, whereas electrostatic effect only plays an unimportant role.

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Ion-molecule reactions of four isomeric cyclopropane derivatives were investigated under chemical ionization(CI) conditions, using methane, acetone and vinyl acetate as reagent gases, The methane positive-ion CI mass spectra of each of two isomer pairs 1,2 and 3,4 are identical, and so are the collision-induced dissociation (CTD) spectra of the protonated molecules of each of the two isomer pairs, The protonation reactions for the isomer pairs 1,2 and 3,4 occurred on the sites of the carboxyl groups and the R groups, respectively, Differences between isomers 1 and 2 are observed in their acetone (A) positive-ion CI mass spectra and in the CID spectra of their adduct ions ([M+H+A](+)), The adduct ions of compounds 2, 3 and 4 with protonated acetone and with protonated acetone dimer are observed in their CI mass spectra, However, only the adduct ions of compound 1 with protonated acetone appear in its CI mass spectrum, The protonated dimers of each of the four compounds are found in their vinyl acetate positive-ion CI mass spectra, and the CID spectra of these dimers for isomers 1 and 2 can also reflect their stereostructural difference. (C) 1998 John Wiley & Sons, Ltd.

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The reaction of anhydrous PrCl3 with Na(C9H7) in 1.2 mole ratio in THF gives [(C9H7)(2)PrCl(THF)](2)1. 1 crystallized in monoclinic system, space group P2(1)/c with a = 7.808(2), b = 17.796(6), c = 14.070(4) Angstrom, beta = 93.97(2)degrees, V= 1950.3(9) Angstrom(3), Dcalcd = 1.63 g/cm(3) and Z = 2. Each Pr ion is surrounded by two indenyl, two Cl and one THF in a roughly trigonal bipyramid arrangement with average Pr-C(ring) and Pr-Cl distances of 2.81 and 2.84 Angstrom. The reaction of LaCl3 with Na(C9H7) in 1:3 mole ratio gives (C9H7)(3)LaTHF 2, which crystallizes in the monoclinic space group P2(1)/a with unit cell constants a = 21.871(8), b = 10.585(3), c = 23.652(7) Angstrom,beta = 114.62(2)degrees, V = 4977.9 Angstrom(3) and Z = 8. (C) 1997 Elsevier Science S.A.

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A series of novel aromatic diamines (1-3) containing kinked cyclohexylidene moieties was synthesized by a reaction of excess aniline and corresponding methyl-substituted cyclohexanone derivatives. The structures of (1-3) were identifield by H-1 NMR, C-13 NMR, and FT-IR. The polymers were synthesized from the obtained diamines and various aromatic dianhydrides by the conventional polycondensation reaction followed by chemical imidization as well as high-temperature one-step polymerization. The inherent viscosities and weight-average molecular weights of the resulting polyimides were in the ranges of 0.55-1.58 dL/g and (7.4-15.2) x 10(4) g/mol, respectively. The prepared polyimides showed excellent thermal stabilities and good solubility. All polymers were readily soluble in common organic solvents such as tetrahydrofuran, chloroform, tetrachloroethane, etc., and the glass transition temperatures were observed at 290-372 degrees C.

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Soluble poly (o-toluidine) (POT), poly(o-anisidine) (PAs) and poly (o-chloroaniline) (PCAn) were doped with camphorsulfonic acid (CSA). The conductivity and UV-Vis spectra of the CSA-doped POT, PAs and PCAn were studied. These properties were found to be dependent on the solvent used. The cast films from m-cresol solution exhibit more effective doping and higher conductivity.

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Concise probabilistic formulae with definite crystallographic implications are obtained from the distribution for eight three-phase structure invariants (3PSIs) in the case of a native protein and a heavy-atom derivative [Hauptman (1982). Acta Cryst. A38, 289-294] and from the distribution for 27 3PSIs in the case of a native and two derivatives [Fortier, Weeks & Hauptman (1984). Acta Cryst. A40, 646-651]. The main results of the probabilistic formulae for the four-phase structure invariants are presented and compared with those for the 3PSIs. The analysis directly leads to a general formula of probabilistic estimation for the n-phase structure invariants in the case of a native and m derivatives. The factors affecting the estimated accuracy of the 3PSIs are examined using the diffraction data from a moderate-sized protein. A method to estimate a set of the large-modulus invariants, each corresponding to one of the eight 3PSIs, that has the largest \Delta\ values and relatively large structure-factor moduli between the native and derivative is suggested, which remarkably improves the accuracy, and thus a phasing procedure making full use of all eight 3PSIs is proposed.