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Fullerene Unit (fullerene + unit)
Selected AbstractsA theoretical study on fullerene-dizincocene hybridsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 6 2009Guohua Gao Abstract Using the density functional theory, we investigated the possible formation of fullerene-dizincocene hybrids, specifically C60*-Zn-Zn-Cp*, C60*-Zn-Zn-C60*, C70*-Zn-Zn-Cp*, and C70*-Zn-Zn-C70*, where C60*, Cp*, and C70* represent C60(CH3)5, C5(CH3)5, and C70(CH3)5 radicals. Our calculation shows that these hybrids have HOMO-LUMO gaps which are larger than has been experimentally identified for C60*-Fe-Cp. In addition, the strength of the ZnZn bonds is similar to that in Cp*-Zn-Zn-Cp* which was also synthesized recently. Furthermore, heterohybrids, C60*-Zn-Zn-Cp* and C70*-Zn-Zn-Cp* are expected to exist in equilibria with homohybrids, C60*-Zn-Zn-C60* and C70*-Zn-Zn-C70*, in which heterohybrids are much more favored. On the other hand, another hybrid involving Sc3N@C68 as a fullerene unit is not highly probable. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Helical Arrays of Pendant Fullerenes on Optically Active Poly(phenylacetylene)sCHEMISTRY - A EUROPEAN JOURNAL, Issue 4 2005Tatsuya Nishimura Dr. Abstract Novel, optically active, stereoregular poly(phenylacetylene)s bearing the bulky fullerene as the pendant were synthesized by copolymerization of an achiral phenylacetylene bearing a [60]fullerene unit with optically active phenylacetylene components in the presence of a rhodium catalyst. The C60 -bound phenylacetylene was prepared by treatment of C60 with N -(4-ethynylbenzyl)glycine in a Prato reaction. The obtained copolymers exhibited induced circular dichroism (ICD) in solution both in the main-chain region and in the achiral fullerene chromophoric region, although their ICD intensities were highly dependent on the structures of the optically active phenylacetylenes and the solution temperature. These results indicate that the optically active copolymers form one-handed helical structures and that the pendant achiral fullerene groups are arranged in helical arrays with a predominant screw sense along the polymer backbone. The structures and morphology of the copolymers on solid substrates were also investigated by atomic force microscopy. [source] Sugar Balls: Synthesis and Supramolecular Assembly of [60]Fullerene GlycoconjugatesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 16 2007Haruhito Kato Abstract The synthesis and characterization of fully deprotected C60 glycoconjugates 4 and 17 is reported. Bis(,- D -mannopyranosyl)malonamide 4 was obtained by using nucleophilic cyclopropanation chemistry, which in general is a very versatile method for fullerene functionalization. Fullerene sugar 17 contains two dendritic ,- D -mannopyranosides that are connected through two adjacent imino bridges to the all-carbon framework. In this adduct-type of C60, which represents a 1,9-dihydro-1a-aza-1(2)a-homo(C60 - Ih)[5,6]fullerene derivative, the entire 60-,-electron system of the fullerene core is retained. This architecture allows the basic cleavage of the acetyl protection groups of precursor adduct 16 without destruction of the core structure of the fullerene sugar. Dendritic glycoconjugate 17 containing six deprotected sugar building blocks is very soluble in water. The amphiphilic nature of 17 with its cone-shaped structure forces the formation of small supramolecular aggregates in aqueous solutions to shield the hydrophobic fullerene units from the water subphase. DOSY NMR spectroscopy and TEM investigation reveal micellar sugar balls with an extremely narrow size distribution of around 4 nm.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Construction of diads and triads copolymer systems containing perylene, porphyrin, and/or fullerene blocksJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2006Ning Wang Abstract A series of conjugated copolymers containing perylene, porphyrin, and/or fullerene units on the main chain have been synthesized. The structures and photophysical properties of polymers were characterized by FTIR, NMR, UV,vis, and fluorescence spectroscopy, gel permeation chromatography, and cyclic voltammetry. The photoinduced charge transfer properties of the films were also measured by a three-electrode cell technique. A rapid, steady, and reproducible cathodic photocurrent response for each polymer was produced when the film was irradiated by a white light. The SEM and TEM images displayed the aggregation superstructures of the polymers. In chloroform, polySPeZnP2F could form a large quantity of spherical nanoparticles. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5863,5874, 2006 [source] | ||||||||||