Chlorination-promoted skeletal transformation of IPR C₇₆ discovered via trifluoromethylation under the formation of non-IPR C₇₆(CF₃)_nF_m

Abstract

High-temperature chlorination of an Isolated-Pentagon Rule (IPR) D2-C76 fullerene followed by high-temperature trifluoromethylation of non-IPR C76 chlorides with CF3I unexpectedly resulted in a series of non-IPR C76(CF3)nFm compounds. X-ray diffraction study with the use of synchrotron radiation revealed the mixed CF3/F structures of non-classical, non-IPR C76(CF3)14, C76(CF3)14F2, and C76(CF3)16F6.

Chlorination‐Promoted Cage Transformation of IPR C92 Discovered via Trifluoromethylation under Formation of Non‐classical C92(NC)(CF3)22

“…It was recently shown that C 60 is also capable to skeletal transformations when the interaction is carried out at harsher conditions of 420–440 °C . As the further development of the method, two‐stage process, a chlorination followed by trifluoromethylation (Cl/CF 3 ), was proposed . Using the two‐stage method, some CF 3 derivatives of non‐IPR or non‐classical fullerenes have been isolated in the cases of C 60 and C 76 (1) (the numeral in parentheses indicates the number of isomer according to the spiral algorithm).…”

“…). This type of chlorination‐promoted skeletal transformations has been reported for C 60 and some isomers of higher fullerenes such as C 76 (1), C 78 (2), and C 100 (18) . Usually, the SWR transformations occurred, if one or both carbon atoms of a rotating C−C bond are chlorinated.…”

“…In fact, the addition pattern of C 92 ( NC )(CF 3 ) 22 does not reflect the chlorination pattern because CF 3 groups and Cl atoms are characterized by significantly different space demands. In any case, the skeletal transformation from C 92 (38) is assisted by chlorination but not trifluoromethylation as has been also reported for cage transformations of C 60 or C 76 (1) with final products isolated as CF 3 or CF 3 /F derivatives …”

“…In any case, the skeletal transformation from C 92 (38) is assisted by chlorination but not trifluoromethylation as has been also reported for cage transformations of C 60 or C 76 (1) with final products isolated as CF 3 or CF 3 /F derivatives. [6,7] At the same time, there is some doubts concerning the driving forces of SWR2 in C 92 (38) as the source for C 92 (NC)b ecause no fused pentagons are presenti nt he C 92 (NC)c age. An alternative suggestion would be the presence of C 92 (NC)i nt he C 92 fractionu sed for trifluoromethylation.…”

Freisetzung der Spannung kondensierter Fünfringe des Fullerenkäfigs durch chemische Funktionalisierung

“…[42] 3.2.5. C 76 [133] 3.2.6. C 82 ,C 84 [51] Es wurde postuliert, dass diese beiden nichtklassischen Nicht-IPR-Chloride von C 84 aus zwei unterschiedlichen C 86 -basierten nichtklassischen Nicht-IPR-Fullerenchlorid-Vorstufen hervorgehen:( NC)C 86 Cl 24 und (NC)C 86 Cl 26 .B ei (NC)C 86 Cl 26 ist der einzige Siebenring in der Mitte der beiden DFP-Paare wie bei einem Sandwich angeordnet, was eine Folge der Abspaltung einer C 2 -Einheit der Fünfring-Sechsring-Verknüpfungsstellen innerhalb des ursprünglichen IPR-Käfigs C 2 (33)-C 88 ist.…”