Fullerene-containing compounds

No X-ray diffraction studies on structure were performed however, the NMR studies provided evidence that the Co species should have a structure closely related to that of analogous Ru or Rh derivatives whose X-ray structures are known, that is, the Cso unit being 77 -bonded to the metal center via one of its G=C units. Electrochemical reduction has been performed to afford the dianion species. The fullerene unit was shown to be weakly coordinated to Co as it could be easily displaced by smooth electrophiles such as I2, maleic anhydride, or PPhs, regenerating the free C6o- At approximately the same time, Baird et al. studied the electron transfer between Ceo and NaCo(CO)4. This reaction led to a transient compound NaCo(CO)3[C6o], which was unstable and led in refluxing THE solution to NaCo[C6ol 3THF Unfortunately, this carbonyl-free compound could not be analyzed by X-ray diffraction 

A triple scission of a six-membered ring on the surface of C60 leading to one of the most remarkable transformations in metal-fullerene chemistry has been observed in 219. This reaction occurred via addition of CpCo(CO)2 on the bis-methano annulene 218 (Equation (36)). 

Reprinted with permission from Arce, M.-J. Viado, A. L. An, Y.-Z. Khan, S. i. Rubin, Y. 

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Schur D.V., Khotynenko N.G., Scherbakova L.G., Adejev V.M., Golovko E.I., Zaginaichenko SYu. Electrochemical method for synthesis of fullerene-containing compounds and coatings. In Carbon-2004 Int. Confer, on Carbon, Brown University, USA, 2004 198. 

The compounds, which are anodic oxidation products of ethanol and toluene, on the one hand, and oxidation products of the combined solvated donor-acceptor fullerene complex to form the fullerene-containing compound, on the other hand, can form on the anode. 

Bis(zinc porphyrin)-oxoporphyrinogen [(ZnTPP)2-OxP] is an example of a donor-acceptor-type triad. Excitation of the zinc porphyrin gronps leads to an efficient energy or electron transfer in the triad and this process depends on the polarity of the solvent used. Further elaboration of this system was accomplished by complexing this compound and other derivatives with fullerene-containing compounds capable of coordinating at the porphyrin zinc metal ions. The structures of the complexes are shown in Figure 14. 

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. 

So far, all efforts to generate, isolate and characterize heterofuUerenes via Kratsch-mer-Huffman vaporization of graphite in the presence of hetero-element-containing compounds such as boron nitride (BN) or cyanogen (CN)2 have failed. An alternative route for the direct formation of heterofuUerenes is cluster rearrangement within exohedral fullerene derivatives such as iminofullerenes and azafuUeroids. The first hints of success by this approach were obtained from mass spectrometry investigations of the cis-l-diazabishomo[60]fullerene 3 [12], the n-butylamine adduct 4 [12] the 1,2-epiminofullerene 5 [11] and the cluster opened ketolactam 6 [2]. 

Abstract. The work demonstrates a principle possibility to produce the films of fullerenes and fullerene-containing products from their solutions by the electrochemical method. Electrical properties of fullerene solutions have been studied. The proposed method can be used for the special-purpose application of fullerene-containing coatings and for synthesis of fullerene compounds with organic and inorganic substances. 

To date, all the confirmed isolable endohedral fullerenes contain metals either scandium, yttrium, or one of the f-block elements may be encapsulated, and compounds containing up to three metals have been reported. The proportions of the endohedral fiillerenes observed depends upon the manner by which they are extracted from the soot. For lanthanum, predominantly La Cg2 and l. i2 C%o are isolated by solvent extraction techniques, whereas direct sublimation from the soot yields La C6o, La C7o, La C74, and La C82- An explanation for this behavior is that most of the endohedral fullerenes are present as insoluble salts, e.g. [La C6o]" [Ceo], and only La Cg2 and La2 C8o are sufficiently redox stable to be extracted as the neutral molecules. 

Topics that have formed the subjects of reviews this year include contemporary issues in electron transport research, dynamics of bimolecular photoelectron transfer reactions, photophysical properties of functionalised fullerene derivatives, carbon-carbon bond formation via radical ions, photoinduced electron transfer processes in ketone, aldehyde, and ester synthesis, photochemical reactions between arenenitriles and benzylic donors, photo-oxidation of conjugated dienes, photoredox reactions of aromatic nitro compounds, electron transfer-mediated photochemistry of some unsaturated nitrogen-containing compounds, reactions of 02( Ag), carbon dioxide activation by aza-macrocyclic complexes, and photochromism of chalcone derivatives. ... 

The surface of fullerene molecules itself in porous fullerene - containing aerogel probably are screened for the interaction with other organic molecules owing to the bonding of possible 14 aminocompounds with fullerene molecules during the reaction of polycondensation [19]. So to prepare fullerene containing adsorbent with opened for interaction of fullerene molecules with other compounds it is better to modify silica surface by 3-aminopropyltrietoxysilane and then to modify this adsorbent by fullerene molecules. In this case fullerene molecules can be attached to the surface only from one side of molecule and after reaction of modification the pore surface will be covered by fullerene molecules. The pore diameter and specific surface area of prepared adsorbent will be determined... 

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