Synthesis of Fullerene Oxides Containing Both 6,6-Closed Epoxide and 5,6-Open Ether Moieties through Thermolysis of Fullerene Peroxides

Abstract

Thermolysis of the fullerene hexaadduct C(60)(OO(t)Bu)(6) results in cleavage of two O-O bonds and elimination of two tert-butoxy groups to form two isomeric products with the formula C(60)(O)(2)(OO(t)Bu)(4) in comparable yields. The two oxygen atoms exist as two epoxy groups in one isomer 3, and as an epoxy and an ether group in the other isomer 2. Addition of hydroxylamine to 2 opens both the epoxy and the ether moieties to give a cage-opened keto-ketoxime derivative.

A precision structural model for fullerenols

“…8,9 Besides, open-bonded ether structures will also prevail as the corresponding conjugate bases or oxidized radicals of other diols. Indeed, the existence of these structural units has been unambiguously identied in C 60 fullerenols or their derivatives synthesized using the stepwise methods by Gan and coworkers, 15,22,23 supporting the high viability of these structures.…”

“…5 shows the NMR spectra. Compared with the previous NMR characterizations, 15,23,24 13 C-labeled samples which we used here allowed to obtain NMR spectra with a higher resolution and thus to perform a more detailed structural characterization. As shown in Fig.…”

Fullerenes

“…The resulting two isomeric products of C 60 O 2 (OO 0 Bu) 4 form either an epoxy or an ether moiety at the same 5,6-junction, which could serve as a precursor for cage-opened fullerenes. 103 A highly efficient photochemical method for the direct acylation of C 60 which includes the novel reaction of C 60 with carbonyl radicals, mediated by tetrabutylammonium decatungstate catalyst, has been developed. 104 The reaction of C 60 with freshly prepared RCH 2 CH 2 ONa/RCH 2 CH 2 OH (R = H, Me, Et, Ph) in anhydrous toluene in the presence of air unexpectedly afforded fullerene products which contained a C 60 -fused tetrahydrofuran ring skeleton and an acetal moiety.…”

Open-cage fullerenes: towards the construction of nanosized molecular containers

“…The structures of compounds 129 and 132 were clarified through both spectroscopic and single-crystal X-ray analysis. 128 It was found that the ether oxygen atom of the pyran ring in 129 is tilted towards the 6-membered ring; furthermore, the existence of a carbonyl and a ketoxime group in 132 was confirmed. On the basis of spectroscopic data the hydrogen atom in 132 could be either next to the ketoxime group (structure depicted in Scheme 30) or next to the carbonyl group; the exact location of the hydrogen was not determined because of the disorder in the X-ray structure of 132.…”

“…65 The reactivity of hexa-adduct 125 was examined under thermal conditions as well. 128 Heating a solution of 125 in chlorobenzene at 100 1C promotes homolysis of the O-O bond on the central pentagon, eventually providing the two isomeric products 129 and 130, bearing an epoxide and an ether group, and two epoxide moieties respectively (Scheme 30). No interconversion between the two isomers was detected.…”