Read by QxMD icon Read

Fullerene C60

Pavlo O Dral, Timothy Clark
We propose a new approach to the synthesis of AHx@fullerene structures via reactions through the fullerene wall. To investigate the feasibility of the approach, the step-by-step hydrogenation of the template endofullerene N@C60 up to NH4@C60 has been studied using DFT and MP2 calculations. Protonation of the endohedral guest through the fullerene wall is competitive with escape of the guest, whereas reaction with a hydrogen atom is less favorable. Each protonation step is highly exothermic, so that less active acids can also protonate the guest with less accumulation of energy...
June 22, 2017: Physical Chemistry Chemical Physics: PCCP
Suru V John, Christian C De Filippo, Simone Silvestrini, Michele Maggini, Emmanuel Iwuoha
Through a cycloaddition reaction, fullerene (C60) was derivatized with a novel organic compound 5-(benzo[b]thiophen-3-yl)pyridine-3-carbaldehyde to form the processable and stable 3-(benzo[b]thiophene-3yl)-5-fullero-1-methylpyrrolidinepyridine (BTFP) compound. BTFP exhibits close similarities to phenyl-C61-butyric-acid-methyl-ester (PCBM) in terms of first reduction potential values (-0.62 and -0.61 V vs. Ag/AgCl, for BTFP and PCBM, respectively) and lowest occupied molecular orbital (LUMO) energy level values (3...
June 2017: ChemistryOpen
Norihito Fukui, Taeyeon Kim, Dongho Kim, Atsuhiro Osuka
Porphyrin tapes possessing meso-meso β-β β-β triple direct linkages have been targets of extensive studies because of their fully conjugated characteristic π-electronic networks. In this paper, we report porphyrin arch-tapes that bear additional carbonyl group(s) or methylene group(s) inserted between one of the β-β linkage(s) of the porphyrin tapes. The carbonyl-inserted porphyrin arch-tapes were efficiently synthesized by double fusion reactions of β-to-β carbonyl-bridged porphyrin oligomers with DDQ and Sc(OTf)3, and were converted to the methylene-bridged porphyrin arch-tapes via Luche reduction with NaBH4 and CeCl3 followed by ionic hydrogenation with HBF4·OEt2 and BH3·NEt3...
June 23, 2017: Journal of the American Chemical Society
Tao Li, Luoyi Fan, Hao Gong, Zeming Xia, Yanpeng Zhu, Nianqiang Jiang, Gaofeng Liu, Long Jiang, Yang Li, Jiaobing Wang
We report a kind of homoditopic molecular host, janusarene, which has two back-to-back compactly arranged nanocavities for guest complexation. The unique two-face structural feature of janusarene allows it to bind and align various guest compounds, concurrently, which include the spherical pristine fullerene C60 and the planar polycyclic aromatic hydrocarbons (PAHs) such as pyrene, perylene, and 9,10-dimethylanthracene. The host-guest interactions were characterized by single crystal X-ray diffraction. A pairwise encapsulation of the PAH guests by janusarene enables us to obtain PAH dimers which deliver emerging spectroscopic properties distinct from those of PAHs dissolved in solution, or in the bulk state...
June 16, 2017: Angewandte Chemie
Francis D'Souza, Shuai Shao, Habtom Gobeze, Paul Karr
BF2-chelaed dipyrromethene, BODIPY, was functionalized to carry two stryryl crown ether tails and a secondary electron donor at the meso-position. Using a 'two-point' self-assembly strategy, a bis-alkyl ammonium functionalized fullerene, C60 was allowed to self-assemble the crown ether voids of BODIPY to obtain multi-modular donor-acceptor conjugates. As a consequence of the two-point binding, the 1:1 stoichiometric complexes formed yielded complexes of higher stability in which fluorescence of BODIPY was found to be quenched suggesting occurrence of excited state processes...
June 13, 2017: Chemistry, An Asian Journal
Li-Yun Yang, Si-Yu Hua, Zhi-Qiang Zhou, Guan-Chao Wang, Feng-Lei Jiang, Yi Liu
Fullerenols, known as polyhydroxylated derivatives of fullerene, have attracted great attention due to their distinctive material properties and potential applications in biology and medicine. As a step toward the elucidation of basic behavior in biological systems, a variety of spectroscopic measurements as well as isothermal titration calorimetry (ITC) were applied to study the interaction between fullerenol (C60(OH)44) and serum proteins (bovine serum albumin (BSA) and γ-globulins). The results of fluorescence spectra indicated that the intrinsic fluorescence of proteins could be effectively quenched by the dynamic mechanism...
May 31, 2017: Colloids and Surfaces. B, Biointerfaces
Francis D'Souza, Yi Hu, Michael Thomas, Waruna Jinadasa, Hong Wang
Simultaneous occurrence of energy and electron transfer events involving different acceptor sites in a newly assembled supramolecular triad comprised of covalently linked free-base porphyrin-zinc porphyrin dyad, H2P-ZnP axially coordinated to electron acceptor fullerene, has been successfully demonstrated. The dyad was connected through the -pyrrole positions of the porphyrin macrocycle for better electronic communication. Interestingly, the -pyrrole functionalization modulated the optical properties to such an extent that it was possible to selectively excite the ZnP entity in the supramolecular triad...
June 7, 2017: Chemistry: a European Journal
Bettina D Gliemann, Volker Strauss, Jakob F Hitzenberger, Pavlo O Dral, Frank Hampel, Jean-Paul Gisselbrecht, Thomas Drewello, Walter Thiel, Dirk M Guldi, Milan Kivala
We describe the synthesis and the electronic and photophysical characterization of novel N-heterotriangulene derivatives decorated with methoxycarbonyl- and methylsulfanyl-substituted dithiafulvenyl moieties. The association of these electron-rich compounds with fullerene C60 as electron acceptor was investigated by means of photophysical, voltammetric, and mass spectrometric methods and rationalized by DFT calculations. Importantly, light-induced interactions between the dithiafulvene-substituted N-heterotriangulene bearing methoxycarbonyl substituents with C60 leads to cooperative fluorescence...
June 2, 2017: Chemistry: a European Journal
Michael Renzler, Lorenz Kranabetter, Marcelo Goulart, Paul Scheier, Olof Echt
We report on the formation and ionization of cesium and C60Cs clusters in superfluid helium nanodroplets. Size distributions of positively and negatively charged (C60) m Cs n(±) ions have been measured for m ≤ 7, n ≤ 12. Reproducible intensity anomalies are observed in high-resolution mass spectra. For both charge states, (C60) m Cs3(±) and (C60) m Cs5(±) are particularly abundant, with little dependence on the value of m. Distributions of bare cesium cluster ions also indicate enhanced stability of Cs3(±) and Cs5(±), in agreement with theoretical predictions...
May 25, 2017: Journal of Physical Chemistry. C, Nanomaterials and Interfaces
Dexuan Xu, Yang Gao, Wanrun Jiang, Zhigang Wang
First-principles calculations show that a carbon adatom defect at the Def[5, 6] site on the surface of C60 can produce a more stable spin-polarized singlet electronic state instead of a magnetic triplet state. This is clearly different from the cases of graphene and nanotubes. The mechanism results from the electron population of the adatom, which produces antiferromagnetic coupling around the C60 cage and the adatom itself. Our calculations show the same phenomenon occurs in other IPR fullerenes, such as C70 and C80...
May 31, 2017: Nanoscale
Jie Guan, David Tománek
Superconducting behavior even under harsh ambient conditions is expected to occur in La@C60 if it could be isolated from the primary metallofullerene soot when functionalized by CF3 radicals. We use ab initio density functional theory calculations to compare the stability and electronic structure of C60 and the La@C60 endohedral metallofullerene to their counterparts functionalized by CF3. We found that CF3 radicals favor binding to C60 and La@C60 and have identified the most stable isomers. Structures with an even number m of radicals are energetically preferred for C60 and structures with odd m for La@C60 due to the extra charge on the fullerene...
June 14, 2017: Nano Letters
Eduardo Victor Peris, Carmen Mejuto, Luis Escobar, Gregorio Guisado-Barrios, Pablo Ballester, Dmitry Gusev
The deprotonation of a corannulene-based bisazolium salt allowed to prepare a corannulene-based NHC di-Au(I) complex. The prepared di-Au(I)-complex was tested in the recognition of fullerene-C60, demonstrating good binding affinity in toluene solution, and producing a host:guest complex with 3:1 stoichiometry, as evidenced by a combination of NMR and ITC titrations. The experimental results are fully supported by DFT calculations. The binding of C60 with the di-Au(I) complex in toluene solution is enthalpically and entropically favored...
May 26, 2017: Chemistry: a European Journal
Tao Wei, M Eugenia Pérez-Ojeda, Andreas Hirsch
An unprecedented hybrid dumbbell consisting of a metallofullerene and an empty fullerene was afforded via simple click reaction of suitable precursor derivatives of Sc3N@C80 and a C60 hexakisadduct.
May 30, 2017: Chemical Communications: Chem Comm
Liting Ju, Pingxiao Wu, Xiaolin Lai, Shanshan Yang, Beini Gong, Meiqing Chen, Nengwu Zhu
In this study, ZnAlTi layered double hydroxide (ZnAlTi-LDH) combined with fullerene (C60) was fabricated by the urea method, and calcined under vacuum atmosphere to obtain nanocomposites of C60-modified ZnAlTi layered double oxide (ZnAlTi-LDO). The morphology, structure and composition of the nanocomposites were analyzed by Scanning Electron Microscopy, High-resolution transmission electron microscopy, X-ray diffraction patterns, Fourier transform infrared and specific surface area. The UV-vis diffuse reflectance spectra indicated that the incorporation of C60 expanded the absorption of ZnAlTi-LDO to visible-light region...
May 23, 2017: Environmental Pollution
Yuchun Liu, Ling Xu, Chen Zhao, Ming Shao, Bin Hu
Fullerene (C60) is an important n-type organic semiconductor with high electron mobility and low thermal conductivity. In this work, we report the experimental results on the tunable Seebeck effect of C60 hybrid thin-film devices by adopting different oxide layers. After inserting n-type high-dielectric constant titanium oxide (TiOx) and zinc oxide (ZnO) layers, we observed a significantly enhanced n-type Seebeck effect in oxide/C60 hybrid devices with Seebeck coefficients of -5.8 mV K(-1) for TiOx/C60 and -2...
June 7, 2017: Physical Chemistry Chemical Physics: PCCP
Daniel Waas, Florian Rückerl, Martin Knupfer, Bernd Büchner
We have used photoelectron spectroscopy to determine the energy-level alignment at organic heterojunctions made of manganese phthalocyanine (MnPc) and the fullerene C60. We show that this energy-level alignment depends upon the preparation sequence, which is explained by different molecular orientations. Moreover, our results demonstrate that MnPc/C60 interfaces are hardly suited for application in organic photovoltaic devices, since the energy difference of the two lowest unoccupied molecular orbitals (LUMOs) is rather small...
2017: Beilstein Journal of Nanotechnology
Rebecca Sure, Andreas Hansen, Peter Schwerdtfeger, Stefan Grimme
We investigate all 1812 isomers of the fullerene C60 consistently with high-accuracy quantum chemistry methods. The isomers are optimized at the PBE-D3/def2-TZVP level of theory and their relative energies are obtained at the affordable and accurate hybrid-DFT level PW6B95-D3(ATM)/def2-QZVP. For the first time reliable values for the relative energy distribution among the 1812 isomers (maximum value of 549.1 kcal mol(-1), average value of 189.8 ± 46.8 kcal mol(-1), 1267 isomers in an energy window of 150-250 kcal mol(-1)) are given...
June 7, 2017: Physical Chemistry Chemical Physics: PCCP
Norman A Lapin, Martyna Krzykawska-Serda, Sean Dilliard, Yuri Mackeyev, Maciej Serda, Lon J Wilson, Steven A Curley, Stuart J Corr
The aim of this study is to understand the combined and differential biokinetic effects of radiofrequency (RF) electric-field hyperthermia as an adjunctive therapy to [60]fullerene nanoparticle-based drug delivery systems in targeting the micro-vasculature and micro-environments of breast cancer tumors. Intravital microscopy (IVM) is an ideal tool to provide the spatial and temporal resolution needed for quantification in this investigation. The water-soluble and fluorescent [60]fullerene derivative (C60-serPF) was designed to be an amphiphilic nanostructure, which is able to cross several biological membranes and accumulate in tumor tissues by passing through abnormally leaky tumor blood vessels...
May 17, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
Marialuisa Siepi, Jane Politi, Principia Dardano, Angela Amoresano, Luca De Stefano, Daria Maria Monti, Eugenio Notomista
Fullerenes, allotropic forms of carbon, have very interesting pharmacological effects and engineering applications. However, a very low solubility both in organic solvents and water hinders their use. Fullerene C60, the most studied among fullerenes, can be dissolved in water only in the form of nanoparticles of variable dimensions and limited stability. Here the effect on the production of C60 nanoparticles by native and denatured hen egg white lysozyme, a highly basic protein, has been systematically studied...
May 19, 2017: Nanotechnology
Piotr Piotrowski, Joanna Pawłowska, Jarosław Grzegorz Sadło, Renata Bilewicz, Andrzej Kaim
C60TEMPO10 catalytic system linked to a microspherical gold support through a covalent S-Au bond was developed. The C60TEMPO10@Au composite catalyst had a particle size of 0.5-0.8 μm and was covered with the fullerenes derivative of 2.3 nm diameter bearing ten nitroxyl groups; the organic film showed up to 50 nm thickness. The catalytic composite allowed for the oxidation under mild conditions of various primary and secondary alcohols to the corresponding aldehyde and ketone analogues with efficiencies as high as 79-98%, thus giving values typical for homogeneous catalysis, while retaining at the same time all the advantages of heterogeneous catalysis, e...
2017: Journal of Nanoparticle Research: An Interdisciplinary Forum for Nanoscale Science and Technology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"