Fullerene, dendrimer

Braun M, Atalick S, Guldi Dirk M, Lanig H, Brettreich M, Burghardt S, Hatzimarinaki M, Ravanelli E, Prato M, Van Eldik R, Hirsch A (2003) Electrostatic Complexation and Photoinduced Electron Transfer between Zn-Cytochrome c and Polyanionic Fullerene Dendrimers. Chem. Eur. J. 9 3867-3875. 

Various covalent and non-covalent approaches for the incorporation of fullerene building blocks into liquid crystalline mesomorphic materials have been developed [35]. Lyotropic mesophases (buckysomes) were obtained upon dissolving globular amphiphilic fullerene dendrimers in water [145]. 

Owing to their spheroidal molecular shape, fullerenes represent attractive functional core units for light-harvesting dendritic systems. In fullerene dendrimers of... 

Fig. 5.11 Zeroth- to second-generation fullerene dendrimers (according to Nierengarten et al.)...

Figure 4. Frechet et al. [26] have reported the first fullerene dendrimer.

Other examples include the fullerene dendrimer 57 [61] with a molecular mass of 7344 Da, dendrimer 59 featuring a bis(l,10-phenanthroline)copper(II) core and 16 peripheral fullerene groups (molecular mass 31601 Da) [72,73], and porphyrin derivatives with two [74] and four (58) [75] appended fullerenes. 

The two fullerene-dendrimer conjugates (Scheme 6) constitute one of the rare examples of fullerene derivatives able to give stable monomolecular Langmuir films, which also do not show aggregation at the air-water interface. The monolayers were transferred onto quartz slides with relatively good transfer ratios for the up cycles [60]. 

FIGURE 2.6 Examples of different approaches of Diels-Alder reaction (a) direct formation of a fullerene dendrimer and (b) fullerene-TTF derivatives synthesized by the generation in situ of the corresponding diene. 

Nierengarten JF, Habicher T, Kessinger R, Cardullo F, Dieder-ich F, Gramlich V, Gisselbrecht JP, Boudon C, Gross M. Mac-rocyclization on the fullerene core direct regio and diastereoselective multi-functionalization of [60]fullerene, and synthesis of fullerene- dendrimer derivatives. Helv. Chim. Acta 1997 80 2238-2276. 

Entries on new materials, including re-cyclate plastics, fullerenes, hard-surfaced polymers, dendrimers, transflective materials, rapid prototyping materials, silicone nitride, supercritical fluids, bulk molding compounds, conversion coatings, folic acid, replacements for chloro-fluorocarbons ... 

Fullerenes possess electronic and photophysical properties which make them natural candidates for the preparation of functional dendrimers. The attachment of a controlled number of dendrons on a core provides a compact insulating layer around the carbon sphere, and the... 

Keywords. Dendrimers, Fullerenes, Optical limitation. Photophysical properties, Thin films... 

The ability of a dendritic shell to encapsulate a functional core moiety and to create a specific site-isolated microenvironment capable of affecting the molecular properties has been intensively explored in recent years [19]. A variety of experimental techniques have been employed to evidence the shielding of the core moiety and to ascertain the effect of the dendritic shell [19, 20]. Dendrimers with a fullerene core appear to be appealing candidates to evidence such effects resulting from the presence of the surrounding dendritic branches. Effectively, the lifetime of the first triplet excited state of fullerene derivatives... 

Both energy and electron transfer quenchers have been employed to show that the quenching rates of the fullerene triplet state are decreased as a function of the size of the dendrimer shell [36]. These results further demonstrate that fullerene is an excellent functional group to probe the accessibility of a dendrimer core by external molecules. 

Light-Harvesting Dendrimers with a Fullerene Core... 

All the fullerene-containing dendrimers reported to date have been prepared with a Cgo core but never with fullerene units at their surface or with Cgg spheres in the dendritic branches. We have recently started a research program on the synthesis of dendrons substituted with fullerene moieties. These fulleroden-drons are interesting building blocks for the preparation of monodisperse fullerene-rich macromolecules. In addition, they are also amphiphilic compounds capable of forming stable Langmuir films at the air-water interface. 

In a recent study, poly(aryl ether) dendritic branches terminated with triethyleneglycol chains were attached to Cgg [66] dendrimer 32 represents the fourth generation. The photophysical properties of these fullerodendrimers have been systematically investigated in three solvents, namely toluene, dichloromethane, and acetonitrile. On increasing dendrimer generation, it has been found that in each solvent (i) the maximum of the fullerene fluorescence band is red-shifted... 

The following sections discuss many of the major particle types and provide bioconjugation options for the coupling of ligands to the surface of functionalized particles. Some additional nanoparticle constructs, including gold particles, dendrimers, carbon nanotubes, Buckyballs and fullerenes, and quantum dots are discussed more fully elsewhere (see Chapter 7 Chapter 9, Section 10 Chapter 15 and Chapter 24). 

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