Synthesis, Structure, and Theoretical Study of Trifluoromethyl Derivatives of the IPR Isomer of C84 Fullerene, C84(11)(CF3)10,12,14

Abstract

AbstractC84 is the most abundant higher fullerene which is present in the arc‐discharge fullerene soot. Among 24 topologically possible Isolated‐Pentagon Rule isomers of C84, two major isomers, C84(22) and C84(23), and several minor ones have been identified experimentally. We report the synthesis, HPLC isolation, and synchrotron X‐ray structure elucidation of trifluoromethyl derivatives of the most abundant minor isomer of C84, C84(11)(CF3)10,12,14. The experimentally determined addition patterns are discussed in terms of the attachments in ribbons of edge‐sharing para C6(CF3)2 hexagons and the uniform distribution of CF3 groups on the C2‐C84(11) carbon cage. A general scheme of C84(11) trifluoromethylation pathways was proposed on the basis of theoretical DFT calculations of formation energies. Thus, trifluoromethylation pathways are now discussed in details for five different isomers of C84.