共查询到20条相似文献,搜索用时 15 毫秒
1.
Natalia V. Avramenko M. V. Korobov Aksana M. Parfenova P. A. Dorozhko Natalia A. Kiseleva P. V. Dolgov 《Journal of Thermal Analysis and Calorimetry》2006,84(1):259-262
In an effort to improve
understanding of dissolution behaviour of fullerenes and their simple chemical
derivatives the binary systems of C60, C70
and the piperazine monoadduct of [60] fullerene C60
N2C4H8
with a series of aromatic solvents have been studied by means of DSC. In certain
systems solid solvates have been found to be the thermodynamically stable
phases relative to saturated solution at room temperature. Identified solid
solvates were characterized by their compositions, temperatures and enthalpies
of incongruent melting transitions. The regularities in thermodynamic stability
of the solvated crystals have been discussed along with dissolution properties
of fullerenes and the derivative. Certain correlations have been observed. 相似文献
2.
Maria João Brites Susana Nascimento Bárbara Gigante Mário N. Berberan-Santos 《Tetrahedron letters》2004,45(37):6927-6930
New polyads were obtained by covalently linking a coumarin dye to a fullerene (C60) following two different strategies: 1,3-dipolar cycloaddition reaction of azomethine ylides or by cyclopropanation reaction. The new polyads are spectroscopically characterized and their fluorescence properties, including the observation of efficient singlet-singlet energy transfer, reported. 相似文献
3.
Bhattacharya S Nayak SK Chattopadhyay S Ghosh K Banerjee M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,67(5):1257-1262
To improve the selectivity ratio of C70 over C60, a new designer molecule, viz., 3-fluoromesotetraphenylporphyrin (1) has been reported in the present investigations. Fluorescence studies reveal that the Q-absorption band of 1 gets sufficient quenching effect upon addition of both C60 and C70. Binding constants (K) of the C60/1 and C70/1 complexes are estimated to be 580 and 10,800 dm3 mol(-1), respectively. Thus, K(C70)/K(C60) is approximately 19 which is very large and even comparable with other macrocyclic host molecules like calix[5]arene, azacalix[m]arene[n]pyridine, cyclotriveratrylenophane and calixarene bisporphyrin. 1H NMR chemical shift measurements show that the -NH- proton of 1 suffers more shifts in presence of C70 compared to C60. This finding also offers a good support in favor of high K value for C70/1 complex as well as large selectivity ratio of C70 over C60. 相似文献
4.
Reaction of C60 with acyl hypohalogenites CF3COOBr or CF3COOI in the presence of water affords an orthoester-type 1,3-dioxolanofullerene in 40-50% yield. This method cannot be applied for the synthesis of 1,3-dioxolanofullerenes bearing aryl- or alkyl-groups since they undergo non-selective halogenation under the reaction conditions. 相似文献
5.
Chun-Yang Jina Dao-Dao Zhang Tetsuya Oguma Shi-Xiong Qian 《Journal of inclusion phenomena and macrocyclic chemistry》1996,24(4):301-310
Cycloisomalto-heptaose (CI-7) and cycloisomalto-octaose (CI-8) are two novel cyclodextrans. Treatment with C60 or C70 by kneading leads to the formation of four distinct water-soluble inclusion complexes: CI-7/C60 (2: 1), CI-8/C60 (2: 1), CI-7/C70 (2: 1) and CI-8/C70 (2: 1). Their formation and structures have been examined by UV vis spectroscopy, X-ray powder diffraction and fluorescence spectral studies. The reaction is a reversible process. 相似文献
6.
7.
Tainah Dorina Marforio Edoardo Jun Mattioli Francesco Zerbetto Matteo Calvaresi 《Molecules (Basel, Switzerland)》2022,27(6)
The persistency of COVID-19 in the world and the continuous rise of its variants demand new treatments to complement vaccines. Computational chemistry can assist in the identification of moieties able to lead to new drugs to fight the disease. Fullerenes and carbon nanomaterials can interact with proteins and are considered promising antiviral agents. Here, we propose the possibility to repurpose fullerenes to clog the active site of the SARS-CoV-2 protease, Mpro. Through the use of docking, molecular dynamics, and energy decomposition techniques, it is shown that C60 has a substantial binding energy to the main protease of the SARS-CoV-2 virus, Mpro, higher than masitinib, a known inhibitor of the protein. Furthermore, we suggest the use of C70 as an innovative scaffold for the inhibition of SARS-CoV-2 Mpro. At odds with masitinib, both C60 and C70 interact more strongly with SARS-CoV-2 Mpro when different protonation states of the catalytic dyad are considered. The binding of fullerenes to Mpro is due to shape complementarity, i.e., vdW interactions, and is aspecific. As such, it is not sensitive to mutations that can eliminate or invert the charges of the amino acids composing the binding pocket. Fullerenic cages should therefore be more effective against the SARS-CoV-2 virus than the available inhibitors such as masinitib, where the electrostatic term plays a crucial role in the binding. 相似文献
8.
Systematic studies on eight isomers of C70O were performed by means of INDO methods. It has been indicated that the O atom is mainly added to the C1-C2 or C3-C3 bond and an epoxide feature with Cs symmetry is formed. Based on the optimized geometries, the UV-Vis spectra were calculated. It has been found that the main
peaks of C70O resemble those of C70 and the characteristic absorptions beyond 460 nm are produced, which is in agreement with the experimental results. Theoretical
assignments about the absorptions were canied out and the reason for the red-shift of the absorptions was discussed. C70O is probably composed of four isomers according to the calculated results.
Project supported by the National Natural Science Foundation of China. 相似文献
9.
Natalia B. Shustova Igor V. Kuvychko Sergey F. Lebedkin Lothar Dunsch Konrad Seppelt Olga V. Boltalina 《Journal of fluorine chemistry》2010,131(11):1198-1212
New experimental results on perfluoroalkylation of C60 and C70 with the use of RfI (Rf = CF3, C2F5, n-C3F7, n-C4F9, and n-C6F13), along with a critical overview of the existing synthetic methods, are presented. For the selected new fullerene (Rf)n compounds we report spectroscopic, electrochemical and structural data, including improved crystallographic data for the isomers of C70(C2F5)10 and C60(C2F5)10, and the first X-ray structural data for the dodecasubstituted perfluoethylated C70 fullerene, C70(C2F5)12, which possesses unprecedented addition pattern. 相似文献
10.
(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
11.
Wangqiao Chen Qian Zhang Teddy Salim Sandy Adhitia Ekahana Xiangjian Wan Tze Chien Sum Yeng Ming Lam Alfred Hon Huan Cheng Yongsheng Chen Qichun Zhang 《Tetrahedron》2014
A novel C60 solar cell acceptor (BTOQC, benzo[2,1,3]-thiadiazole-o-quinodimethane-C60 bisadducts) based on benzo[2,1,3]thiadiazole has been synthesized as model to study how the thiadiazole group will affect the device performance in bulk heterojunction organic photovoltaics (BHJ-OPV) with poly(3-hexylthiophene) (P3HT) as donor. The optoelectronic, electrochemistry, and photovoltaic properties of the novel bisadduct BTOQC have been fully investigated. The best device performance of this fullerene derivative in our research was obtained as 2.50% with a high Voc of 0.74 V. 相似文献
12.
Nitrogen-doped TiO2 (N-TiO2) were prepared by the impregnation method using urea as a nitrogen source and TiO2-P25 as precursor. N-TiO2 was characterized by x-ray diffraction (XRD), UV–vis diffusion reflectance spectra (UV–vis DRS), Fourier transform infrared spectroscopy (FTIR), and x-ray photoelectron spectroscopy (XPS) techniques. XPS analysis indicates the incorporation of nitrogen in TiO2 lattice as O–Ti–N linkage. DRS spectra reveal the extended absorption to the visible range. Photocatalytic performance of the N-TiO2 was studied by testing the degradation rate of aqueous styrene under visible light. Also, the degradation kinetics of aqueous styrene and possibility of cyclic usage of N-TiO2 were investigated. 相似文献
13.
A series of 4-aziridino[C60]fullerene-1,8-naphthalimide (C60-NI) dyads 4 ([6,6]-closed ring) were synthesized as the only addition product from the reaction of C60 with the corresponding azide compounds 3 under microwave irradiation in good yield. A quenching of fluorescence was shown in dyads 4, and this decay was evidenced to be an intramolecular process. 相似文献
14.
C60/C70键联1,4-二-(咔唑-9-亚甲基)苯的电化学行为与双光子吸收 总被引:1,自引:1,他引:0
设计合成了C60键联1,4-二-(咔唑-9-亚甲基)苯(5)和C70键联1,4-二-(咔唑-9-亚甲基)苯(6), 用红外、核磁共振和MALDI-TOF质谱进行了表征, 确认了化合物5和6的结构, 用循环伏安法研究了化合物5和6的电化学性质, 并用Z扫描对其双光子吸收性质进行了研究. 相似文献
15.
Ping Yan Cheng-Bo TianCong-Li Gao Qianyan ZhangZhuang-Ping Zhan Su-Yuan XieRong-Bin Huang Lan-Sun Zheng 《Tetrahedron》2014
Regioselective reaction of C60Cl6 with thioamides via a radical annulation to form fullereno thiazole derivatives is reported. The reaction is promoted by K2CO3, which might deprotonate thioamide to initiate a single electron transfer from thioamide anion to C60Cl6. The experiments with various thioamides establish the proposed base-promoted reaction as a facile route for synthesis of fullereno fused thiazole derivatives starting from C60Cl6, a prevalent synthon in fullerene chemistry. In addition, the tunable electrochemical properties of the fullereno thiazole products have been investigated for their potential photovoltaic application. 相似文献
16.
Dong Geun Jo Changeun Kim Sinjae Lee Sooyeon Yun Seewon Joung 《Molecules (Basel, Switzerland)》2022,27(5)
In this study, we describe the synthesis of cyclic N-acyl amidines from readily available N-heteroarenes. The synthetic methodology utilized the versatile N-silyl enamine intermediates from the hydrosilylation of N-heteroarenes for the [3 + 2] cycloaddition reaction step. We evaluated various acyl azides and selected an electronically activated acyl azide, thereby achieving a reasonable yield of cyclic N-acyl amidines. We analyzed the relationship between the reactivity of each step and the electronic nature of substrates using in situ nuclear magnetic resonance spectroscopy. In addition, we demonstrated gram-scale synthesis using the proposed methodology. 相似文献
17.
Efficient, mild, and quantitative procedures for the synthesis of functionalized benzo[c]chromeno[2,3-a]phenazine derivatives by one-pot, four-component condensation of 2-hydroxynaphthalene-1,4-dione, 1,2-phenylenediamines, aromatic aldehydes, and cyclic 1,3-dicarbonyl compounds have been developed using catalytic amounts of H2SO4 and phosphotungstic acid in EtOH/H2O (1:1) under reflux and also with [NMP]H2PO4, which acts as catalyst and medium at 80 °C. The reaction avoids tedious workup procedure due to the direct precipitation of products from the reaction medium. The present finding provides promising synthetic strategies for the synthesis of libraries with functional group diversity. 相似文献
18.
A simple KF/Al2O3-catalyzed reaction of 1,3-diaryl-2-propen-1-one and 2,6-diamino-4-hydroxylpyrimidine in ethyl alcohol gave aromatized 5,7-diarylpyrido[2,3-d]pyrimidine derivative by air oxidation. On the other hand, the unaromatized intermediate products were isolated under dry nitrogen successfully. A possible reaction mechanism with two pathways to lose water was proposed based on the further experimental results; one of them was confirmed by 1H NMR spectra of isolated intermediate product. 相似文献
19.
Geert-Jan M. Meppelder 《Journal of organometallic chemistry》2006,691(14):3206-3211
Reaction of [{(R)-C20H12O2}Ti(OiPr)2] with 1,4-dithiaalkanediyl-2,2′-bis(6-tert-butyl-4-methyl-phenol) affords the chiral-at-metal complex [{(R)-C20H12O2}Ti{(C6H2O-tBu-6-Me-4)2S(CH2)2S}] (1) in low diastereomeric excess. Complex 1 can be partially hydrolyzed to give a dinuclear species [μ-{(R)-C20H12O2}-μ-O-{(Λ)-Ti[(C6H2O-tBu-6-Me-4)2S(CH2)2S]}2] (2), in which the two titanium centers are homochiral. The molecular structure of 1 and 2 was confirmed by single crystal X-ray analysis, which shows C2-symmetry in both complexes. 相似文献
20.
Pentafluoroethyl derivatives of [60]fullerene C60(C2F5)n (n = 6, 8, and 10) were synthesized by the reaction of C60 with C2F5I in glass ampoules at 380–440 °C. Isomers of composition C60(C2F5)6 (one isomer), C60(C2F5)8 (five isomers), and C60(C2F5)10 (two isomers) were isolated by chromatographic separation. Their molecular structures were established by X-ray diffraction.
The relative stabilities of isomers were compared by density functional theory calculations.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 881–887, May, 2007. 相似文献