Study of molecular complex formation between [60]fullerene and two series of donors by the NMR method

Formation of molecular complexes between [60]fullerene and (i) a series of aromatic hydrocarbons, namely, anthracene, acenaphthene, phenanthrene, pyre ne, durene, pentamethylbenzene, and hexamethylbenzene, and (ii) a series of pyridines, namely, pyridine, 2-picoline, 3-picoline, 4-picoline, 2,6-lutid ine, and 2,4,6-collidine has been studied in CCl4 medium by NMR method. [60 ]Fullerene has been shown to form 1:1 molecular adducts with the above seri es of compounds. Formation constants (K) of the above complexes have been d etermined from the systematic variation of NMR chemical shifts of specific protons of the donors in the presence of C-60. The K values of [60]fulleren e complexes with pyridine, 3-picoline, and 4-picoline yield good estimates of the Hammett constant, rho, for the complexation reaction.