Fullerenes reactivity

Since efficient syntheses have been available, fullerenes (in particular Cso) have been the focus of an explosion of 

Other reactions typical of double-bond character include the formation of cycloaddition products (exemplifled schematically in equation 13.12), and some have been developed to prepare a range of rather exotic derivatives. 

Reactions of Cgo with free radicals readily occur, e.g. photolysis of RSSR produces RS which reacts with Cgo to give CgoSR , although this is unstable with respect to regeneration of Cgo- The stabilities of radical species CgoY are 

The electrochemical reduction of Cgo results in the formation of a series of fulleride ions, [Cgo] where n = 1-6. The midpoint potentials (obtained using cyclic voltammetry and measured with respect to the ferrocenium/ferrocene couple, Fc /Fc = 0 V, ferrocene see Section 23.13) for the reversible one-electron steps at 213 K are given in scheme 13.16. 

Protonation of Ceo has only been observed by superacids of type HCHBiiRsXs (e.g. X = Cl) (see Section 9.9). The solution NMR spectrum of [HCgol shows a single, sharp peak, indicating that the proton migrates over the entire fullerene cage on the NMR timescale. Solid state NMR spectroscopic data (i.e. for a static structure) show that the protonated sp C atom S 56 ppm) is directly bonded to the sp cationic site (S 182 ppm). 

Other reactions typical of double-bond character include the formation of cycloaddition products (exemplified 

The formation of methanofullerenes, CeoCR2, occurs by reaction at either 5,6- or 6,6-edges in Ceo- For the 

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Fullerene reactivity and applications have been explored since being discovered in 1985. Nowadays, this chemistry has been intensely developed, although there is still the possibility to find some new reactions, as recently underlined by Martin... 

The C60 and C70 reactivity with the vegetable oils at first glance could appear as an obstacle in the use of fullerene solutions in vegetable oils. Apart from the fact that one could use fully saturated fatty acids derivatives as vehicle for fullerenes delivery, which are not reactive with them, the formation of adducts between the unsaturated fatty acids and fullerenes could be exploited not only in the stabilization of the systems fullerenes-vegetable oils, but also in the alteration and, may be in the attenuation of the fullerene reactivity in in vivo and in a very gradual release of the fullerenes-fatty acids derivatives in living systems. 

Cardona, C.M., Kitaygorodskiy, A., and Echegoyen, L. (2005) Trimetallic nitride endohedral metallo-fullerenes reactivity dictated by the encapsulated metal cluster. Journal of the American Chemical Society, 127, 10448-10453. 

The driving force of fullerene reactivity most of aU originates from their curved surface. Any addition from the outside to one or more of the already prepyramidal-ized carbon atoms leads to sp -hybridization and thus reduces the strain in the fullerene molecule. An addition from the inside, on the contrary, would increase the strain and consequently is impossible. In addition the overlap of the participating orbitals would be insufficient (Figure 2.33). Endohedrally included atoms or molecules accordingly are not bound to the carbon skeleton, but they exist inside of it as more or less free entity (refer to Section 2.5.4). 

The present voliune combines reports and the current status of the principles of fullerene reactivity, of cluster modified fullerenes, of higher fullerenes and nanotubes and reviews potential applications of fullerene materials. This volume is also meant to inspire interested fullerene researchers to find elegant... 

Barth and Lawton s production of [5]circulene or corannulene 114 (Fig. 1.9) in 1966 [90] was a significant achievement due to the fuDerene-based, nonplanar structure of 114. The 17-step synthesis began with acenaphthene and relied on alkylation, condensation, and Pdaromatization reactions to afford the macrocycle. The following decade would see continued efforts to isolate [7]circulene IIS (Fig. 1.9) but another decade would pass before 115 was successfiilly produced [Id], Sygula and Rabideau discuss more recent work on buckybowls and fiillerene fragments in Chapter 12, whereas fullerene reactivity is outlined by Kitagawa, Mur-ata, and Komatsu in Chapter 9. 

Fullerene Reactivity - Fullerene Cations and Open-Cage Fullerenes... 

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