Fulleroids, rearrangement

In general, open structures II are energetically preferred over the closed forms I [8, 9], In the ring closed isomers I two unfavorable double bonds within five-membered rings would be required. No monoadduct with such a structure has been observed. Fulleroids such as 1-3 are usually formed via rearrangement of their pyrazoline-, triazoline- or ozonide [6,6]-precursor adducts accompanied by extrusion of N2 or O2 (see Chapter 4) [7,10-12]. 

Photochemical fulleroid to methanofiillerene conversion via di-rt-methane rearrangement has been reported by Wudl and coworkers [138]. 

Recently, the electrochemistry of fullerenes and their derivatives has gained much attention [33]. Cgo, C70 and higher fullerenes were reduced electrochemi-cally, and six reduction waves were observed for both Cgo and C70 [34], as well as for most of the higher fullerenes [35]. The energy levels that were obtained from these experiments were mostly in line with MO calculations. The electrochemistry of numerous fullerene derivatives was studied to compare their electron affinities and energy levels with their parent fullerenes. Electrochemically induced isomer-izations can be observed in CV, as is the case in the rearrangement of fulleroids to methanofullerenes [36]. 

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