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The general aim of the work is to develop an effective way for synthesis of perfluorocycloalkano[60]fullerenes, namely perfluoro-1,4-butylene[60]fullerene. Earlier such derivatives were obtained in the high temperature reaction of C60 with C4F8I2 [1]. Photochemical activation has certain advantages: it prevents considerable destruction of the reagent and allows selective impact on the reacting particles. The reactions were performed in toluene solution using different light filters and different duration of irradiation. The conversion of fullerene appeared to be up to 90%. The product was subjected to MALDI-TOF analysis, which showed presence of the products of cycloaddition, but the main peaks corresponded to radical particles C60(C4F8I)n with the number of groups from one to four, of which the most intense signal was C60(C4F8I). Mass spectrometric observation of the post source decay indicates possible presence of free radicals in the samples. ESR study of the reaction products revealed the evidence of long-lived paramagnetic particles with the life time more than 6 h. We also managed to observe the hyperfine structure of ESR-spectra of the active intermediate. These results allowed proposing the following mechanism of the photochemical process: C60 + h → C60* C60* + C4F8I2 → C60+I- + C4F8I∙ C60+I-→ C60 + I∙ C60 + C4F8I∙ → C60C4F8I∙ 2C60C4F8I∙ ↔ (C60C4F8I)2 For the proposed geometry of the active radical the ESR spectrum was theoretically calculated with the use of PRIRODA program package [2]. The results appeared to be in good agreement with the experimental data. This work was supported by the Russian Foundation for Basic research (grants No. 13-03-00311 and No. 12-03-31278). References 1. N. I. Gruzinskaya, A. S. Pimenova, P. A. Khavrel, L. N. Sidorov, E. Kemnitz, S. I. Troyanov, Perfluoroalkylated derivatives of С60 fullerene: C60(C4F8)n (n = 2, 3, 4 and 6), Izv. RAS, Ser. chem., 2009, No 11. 2. D. N. Laikov, Fast evaluation of density functional exchange-correlation terms using the expansion of the electron density in auxiliary basis sets, Chem. Phys. Lett., 1997, v. 281, p. 151–156.