Open cage fullerene

Figure 14.1 Possible derivatizations of Qq- ( ) fullerene salts, (b) exohedral adducts, (c) open cage fullerenes, (d) quos/Tullerenes, (e) heterofullerenes, (f) endohedral fullerenes.

Fig. 2.3 Various Jt-electron conjugated systems constructed on the [60]fuIlerene skeleton. (a) C60Br6. (b, c, d) Open-cage fullerenes with a 14-, 13- and 18-membered orifice,...

Iwamatsu, S., Stanisky, C.M., Cross, R.J. et al. (2006) Carbon monoxide inside an open-cage fullerene. Angewandte Chemie International Edition, 45, 5337-5340. 

Synthesis, structure, and molecular encapsulation of open-cage fullerenes, particularly, possessing heterocyclic fragments 05SL2117. 

Komatsu K, Murata Y, Fujiwara K, Suzuki M, Murata M. Synthesis of new fullerene dimers and open-cage fullerenes by solid-state and liquid-phase reaction of Cgo with N-containing aromatics and with organosilicon compounds. Electrochem Soc Proc 2002 12 291-7. 

Murata Y, Kato N, Komatsu K. The Reaction of fullerene C with phthalazine the mechanochemical solid-state reaction yielding a new C dimer versus the hquid-phase reaction affording an open-cage fullerene. J Org Chem 2001 66 7235-9. 

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

An ether, such as 24 can be produced, when the intermediate cation C59N+ is trapped by an alcohol (Scheme 9.21) [42]. This product contains a carbon atom attached to an oxygen and a nitrogen atom, providing a potential precursor of open-cage fullerenes [42]. 

An Open-Cage Fullerene with a 14-Membered-Ring Orifice... 

Figure 9.4. Open-cage fullerene derivatives having a 12-membered-ring orifice.

Insertion of a Small Guest into Open-Cage Fullerene Derivatives... 

For pristine Geo, insertion of a helium atom ( He) required drastic conditions such as 650 °C and 3000 atm to give He C6o in an incorporation rate of 0.1% [58, 84). The incorporation was improved to 1% when Cso vvas pre-treated with KCN the reason for this is as yet unknown [85]. In contrast, theoretical calculations showed that insertion of a helium atom or a hydrogen molecule into open-cage fullerene 65 would take place under milder conditions such as at 124 or 397 °C for helium or hydrogen, respectively (Scheme 9.35) [59]. Actually, such insertion into 65, which was obtained in a similar maimer as 41, was achieved for the first time in 2001 by Rubin and coworkers [59]. The treatment of 65 as a crystalline powder with He (288-305 °G, ca. 475 atm, 7.5 h) gave the He-encapsulating molecule, He 65, in 1.5% yield. The NMR chemical shift of the He incorporated in 65 appeared at AS = —10.10 ppm relative to the free dissolved He gas. The He atom slowly escaped when He 65 was heated above 80 °C in a solution of... 

If the orifice of an open-cage fullerene encapsulating a guest species can be completely closed while retaining the guest inside, the molecular surgery approach toward the synthesis of endohedral fullerenes is actualized. In 2005, Komatsu and co-workers reported such closure of the orifice of H2 56 by a four-step sequence of... 

Open-cage fullerene derivatives are useful not only for the synthesis of endohe-dral fullerenes as described in this chapter but also for the synthesis of heteroful-lerenes such as C59NH [94] and (Cs9N)z [35]. Thus, there are possibilities that novel heterofullerenes can be obtained from open-cage fullerenes if reactions are developed to insert heteroatoms on the rim of the orifice and to close the orifice... 

Synthesis of an Open-Cage Fullerene with an Eight-membeied-ring Orifice (49)... 

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