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111.
C60 derivatives bearing either terminal alkyne or azide functional groups have been prepared and used as building blocks under the copper-mediated Huisgen 1,3-dipolar cycloaddition conditions leading to 1,2,3-triazole derivatives. 相似文献
112.
113.
Hahn U Gégout A Duhayon C Coppel Y Saquet A Nierengarten JF 《Chemical communications (Cambridge, England)》2007,(5):516-518
Fullerene derivatives bearing a carboxylic acid function undergo self-assembly with n-butylstannonic acid (nBuSn(O)OH) to produce fullerene-rich nanostructures with a stannoxane core in almost quantitative yields. 相似文献
114.
A series of polyacrylonitrile–dimethylsulfoxide–CuX2 (X=CF3SO3−, Cl−, Br−), films (foils) were prepared by means of the solution cast technique. The thickness of the foils was between 0.04 and 0.09 cm and they contained 70–80 wt.% of the solvent. Conductivities of the solid electrolytes were obtained from impedance measurements. The conductivity increases with the increase of the salt content up to 8 wt.%; at higher concentrations (>8 wt.%) the conductivity is more or less stable, and reaches, in the case of Cu(CF3SO3)2 and CuCl2, the level of ca. 10−3 Ω−1 cm−1 at room temperature. The foils based on the CuBr2 show even higher conductivity, close to 10−2 Ω−1 cm−1 at room temperature, a value comparable to that characteristic for liquid solutions. The temperature variation of the conductivity for all the systems studied is of the Arrhenius type. The activation energy, determined from linear plots lnσ=f(T−1), is of the order ca. 14 kJ mol−1 for the PAN/CuBr2/DMSO and of ca. 21 kJ mol−1 for the PAN/CuCl2/DMSO and the PAN/Cu(CF3SO3)2/DMSO systems. 相似文献
115.
Adam Tracz Jeremiasz Jeszka Iwona Kuciska Jean‐Paul Chapel Gisele Boiteux 《Macromolecular Symposia》2001,169(1):129-135
High density polyethylene (PE) was crystallised from the melt on freshly cleaved surface of highly oriented pyrolitic graphite (HOPG) or mica. Atomic force microscopy (AFM) studies of structure of the polymer surface adjacent to the graphite or mica were performed after peeling of from the substrate. Significant differences of crystalline structure on the interface were found between PE crystallised on graphite and mica. The surface of polyethylene crystallised on graphite shows large areas with regularly arranged rectangular structures. These objects (ca 20‐80 nm big) probably represent the nucleation centres of the lamellar growth. The surface of polyethylene crystallised at mica surface shows some dot‐like structures showing no particular arrangement. 相似文献
116.
117.
Delphine Felder Manuel GutirrezNava Maria delPilarCarren Jean‐Franois Eckert Michaël Luccisano Corinne Schall Patrick Masson Jean‐Louis Gallani Benoît Heinrich Daniel Guillon Jean‐Franois Nierengarten 《Helvetica chimica acta》2002,85(1):288-319
Various amphiphilic fullerene derivatives were prepared by functionalization of [5,6]fullerene‐C60‐Ih (C60) with malonate or bis‐malonate derivatives obtained by esterification of the malonic acid mono‐esters 5 – 7 . Cyclopropafullerene 10 was obtained by protection of the carboxylic acid function of 6 as a tert‐butyl ester, followed by Bingel addition to C60 and a deprotection step (Scheme 2). The preparation of 10 was also attempted directly from the malonic acid mono‐ester 6 under Bingel conditions. Surprisingly, the corresponding 3′‐iodo‐3′H‐cyclopropa[1,9][5,6]fullerene‐C60‐Ih‐3′‐carboxylate 11 was formed instead of 10 (Scheme 3). The general character of this new reaction was confirmed by the preparation of 15 and 16 from the malonic acid mono‐esters 13 and 14 , respectively (Scheme 4). All the other amphiphilic fullerene derivatives were prepared by taking advantage of the versatile regioselective reaction developed by Diederich and co‐workers which led to macrocyclic bis‐adducts of C60 by a cyclization reaction at the C‐sphere with bis‐malonate derivatives in a double Bingel cyclopropanation. The bis‐adducts 37 – 39 with a carboxylic acid polar head group and four pendant long alkyl chains of different length were prepared from diol 22 and acids 5 – 7 , respectively (Scheme 9). In addition, the amphiphilic fullerene derivatives 45, 46, 49, 54 , and 55 bearing different polar head groups and compound 19 with no polar head group were synthesized (Schemes 11–13, 15, and 5, resp.). The ability of all these compounds to form Langmuir monolayers at the air‐water interface was investigated in a systematic study. The films at the water surface were characterized by their surface pressure vs. molecular area isotherms, compression and expansion cycles, and Brewster‐angle microscopy. The spreading behavior of compound 10 was not good, the two long alkyl chains in 10 being insufficient to prevent aggregation resulting from the strong fullerene‐fullerene interactions. While no films could be obtained from compound 19 with no polar head group, all the corresponding amphiphilic fullerene bis‐adducts showed good spreading characteristics and reversible behavior upon successive compression/expansion cycles. The encapsulation of the fullerene in a cyclic addend surrounded by four long alkyl chains is, therefore, an efficient strategy to prevent the irreversible aggregation resulting from strong fullerene‐fullerene interactions usually observed for amphiphilic C60 derivatives at the air‐water interface. The balance of hydrophobicity to hydrophilicity was modulated by changing the length of the surrounding alkyl chains or the nature of the polar head group. The best results in terms of film formation and stability were obtained with the compounds having the largest polar head group, i.e. 45 and 46 , and dodecyl chains. Finally, the Langmuir films obtained from the amphiphilic fullerene bis‐adducts were transferred onto solid substrates, yielding high‐quality Langmuir‐Blodgett films. 相似文献
118.
The title compound (C14H8N2O7,M
r
=306.2) crystallizes in the orthorhombic space group Pbca witha=6.962(1).b=24.688(1), andc=15.890(1)Å,V=2731.0 Å3,D
x
=1.489 g·cm–3 forZ=8,=0.98 mm–1,F(000)=1296,T=293 K. FinalR=0.053 for 1873 observed reflections. The structure was solved by direct methods. Approximately planar molecules lie perpendicular to the [100] direction and show partial stacking. The structure is the first example of a symmetric anhydride which does not retain the symmetry in the crystal state. The two independent nitro groups twist out of the ring planes by 10.5 and 14.8°, respectively. 相似文献
119.
120.
A stable C60 derivative bearing an azide functional group was prepared and used as a building block under the copper-mediated Huisgen 1,3-dipolar cycloaddition conditions for the preparation of a fullerene-porphyrin conjugate. 相似文献