Mendeleev Communications Mendeleev Commun., 2008, 18, 27–28 – 27 – © 2008 Mendeleev Communications. All rights reserved. Mixed chlorotrifluoromethyl fullerene C 60 (CF 3 ) 12 Cl 12 Sergey I. Troyanov* a and Erhard Kemnitz b a Department of Chemistry, M. V . Lomonosov Moscow State University, 119992 Moscow, Russian Federation. F ax: +7 495 939 1240; e-mail: stroyano@thermo.chem.msu.ru b Institute of Chemistry, Humboldt University, 12489 Berlin, Germany DOI: 10.1016/j.mencom.2008.01.011 A mixed chlorothifluoromethyl derivative of [60]fullerene, C 60 (CF 3 ) 12 Cl 12 , was prepared by the chlorination of C 60 (CF 3 ) 12 with SbCl 5 at 280 °C. Fullerene chloride, C 60 Cl 6 , reported in 1993, was among the first derivatives obtained after the discovery of fullerenes. 1 Other chlorides such as C 60 Cl 24 , C 60 Cl 28 and C 60 Cl 30 were syn- thesised recently by the reaction of fullerenes with inorganic chlorides (SbCl 5 , VCl 4 , PCl 5 , ICl etc.). 2 The preparation, though as a mixture, of trifluoromethylated fullerenes was first reported in 1993. 3 Since then, a large variety of C 60 (CF 3 ) n compounds with n = 2–18 were synthesised by the reaction of C 60 with compounds easily releasing CF 3 radicals on heating. Their mole- cular structures were unambiguously characterised by X-ray diffraction studies. 4–6 The compound S 6 -C 60 (CF 3 ) 12 is prominent among others in that its synthesis can be carried out with a high selectivity and its crystalline form is negligibly soluble in most organic solvents. 7 Here, we report the first preparation of a mixed chlorotrifluoro- methyl derivative of fullerene, C 60 (CF 3 ) 12 Cl 12 , accomplished by the chlorination of S 6 -C 60 (CF 3 ) 12 with SbCl 5 . The crystal and molecular structures of the new compound were elucidated by X-ray crystallography. Crystalline S 6 -C 60 (CF 3 ) 12 was prepared by the known method using an ampoule reaction of C 60 with CF 3 I. 7 The reaction product was washed out with toluene to remove the traces of other C 60 (CF 3 ) n compounds. It was placed in a two-section glass ampoule together with excess liquid SbCl 5 . The ampoule was evacuated at cooling, sealed off, and then heated in a tube furnace at 270–280 °C for 24 h. At cooling, light yellow crystals were formed, which were separated from remaining SbCl 5 and a small amount of SbCl 3 by their condensation in the other (cooled) section of the ampoule. The isolated compound C 60 (CF 3 ) 12 Cl 12 (30 mg, 90% yield) was structurally characterised by single- crystal X-ray diffraction analysis. † Its IR spectrum is essentially different from that of the starting compound apart for the posi- tions of some IR bands at 1150–1300 cm –1 due to the presence of CF 3 groups (Figure 1). The compound is stable in air; it is practically insoluble in most organic solvents. The thermal stability of the compound is high. According to thermogravi- metric analysis in an inert atmosphere at 1 bar, it decomposes at 360–415 °C with evolution of chlorine immediately followed by sublimation of the remaining C 60 (CF 3 ) 12 at 415–490 °C thus resulting in a complete mass loss. X-ray crystallography revealed that the molecular structure of the new compound retains the addition pattern of CF 3 groups † Crystal data: C 60 (CF 3 ) 12 Cl 12 , crystal dimensions 0.4×0.4×0.2 mm, M = 1974.12, trigonal, space group R3 – c, a = 13.371(2), c = 59.129(11) Å, V = 9155(3) Å 3 , m = 0.709 mm –1 , Z = 6. Data collection was performed with an IPDS (Stoe) at 170 K (MoKα, l = 0.71073 Å). Reflections collected 25515, independent 2626, R int = 0.037. Structure solution with SHELXS97 11 and structure refinement with SHELXL97. 12 Anisotropic refinement with 190 parameters yielded a conventional R 1 (F) = 0.039 for 2364 reflections with I >2s(I) and wR 2 (F 2 ) = 0.104 for all reflections. One of two independent Cl atoms is disordered between two positions with occupancies 0.80 and 0.20, respectively. CCDC 671037 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif. For details, see ‘Notice to Authors’, Mendeleev Commun., Issue 1, 2008. 1400 1200 1000 800 600 400 0 20 40 60 80 399 459 601 723 737 759 798 821 848 891 914 978 994 1012 1050 1116 1179 1234 Intensity (arbitrary units) Figure 1 IR spectrum of C 60 (CF 3 )Cl 12 in a KBr pellet. Figure 2 S 6 -C 60 (CF 3 )Cl 12 molecule viewed along the axes (a) c and (b) b; (c) Schlegel diagrams for S 6 -C 60 (CF 3 )Cl 12 (triangles and circles denote CF 3 groups and Cl atoms, respectively) and (d) C 60 X 24 (circles denote halogen atoms X = Cl or Br). (a) (b) (c) (d)