Pyridine admixtures have a slight effect on the activity and selectivity parameters in the oxidation of alkanes with the O2-H 2O2-vanadate anion-pyrazine-2-carboxylic acid reagent in acetonitrile. This feature distinguishes this reagent, which oxygenates alkanes via the mechanism involving free hydroxyl radicals, from similar systems based on iron complexes that show unusual selectivity in alkane oxidation in the presence of pyridine (Gif systems). The data obtained may indirectly indicate that free hydroxyl radicals do not directly participate in alkane functionalization with the Gif system, at least in the principal reaction route. Copyright © 2005 by MAIK "Nauka/Interperiodica" (Russia).456413418Bagrii, E.I., Nekhaev, A.I., (1989) Zh. Vses. Khim. O-va Im. D. I. Mendeleeva, 34, p. 634Shilov, A.E., Shul'pin, G.B., (1997) Chem. Rev., 97, p. 2879Maravin, G.B., Avdeev, M.V., Bagrii, E.I., (2000) Neftekhimiya, 40, p. 3(2000) Pet. Chem., 40, p. 1Shilov, A.E., Shul'pin, G.B., (2000) Activation and Catalytic Reactions of Saturated Hydrocarbons in the Presence of Metal Complexes, , Kluwer, DordrechtShul'pin, G.B., (2002) J. Mol. Catal., A: Chem., 189, p. 39Shul'pin, G.B., (2003) C. R. Acad. Sci., Chim., 6, p. 163Shul'pin, G.B., (2004) Transition Metals for Organic Synthesis, 2, p. 215. , Ed. by M. Beller and C. Bolm (Wiley-VCH, Weinheim)Barton, D.H.R., Li, T., (1998) Tetrahedron, 54, p. 1735Barton, D.H.R., (1998) Tetrahedron, 54, p. 5805Schuchardt, U., Jannini, M.J.D.M., Richens, D.T., (2001) Tetrahedron, 57, p. 2685Shul'pin, G.B., Nizova, G.V., Kozlov, Y.N., (2004) Adv. Synth. Catal., 346, p. 317Shul'pin, G.B., Süss-Fink, G., Shul'pina, L.S., (2000) Chem. Commun., p. 1131Shul'pin, G.B., Nizova, G.V., (1992) React. Kinet. Catal. Lett., 48, p. 333Shul'pin, G.B., Attanasio, D., Suber, L., (1993) J. Catal., 142, p. 147Shul'pin, G.B., Guerreiro, M.C., Schuchardt, U., (1996) Tetrahedron, 52, p. 13051Shul'pin, G.B., Kozlov, Y.N., Nizova, G.V., (2001) J. Chem. Soc., Perkin Trans., 2, p. 1351De La Cruz, M.H.C., Kozlov, Y.N., Lachter, E.R., Shul'pin, G.B., (2003) New J. Chem., 27, p. 634Kozlov, Y.N., Nizova, G.V., Shul'pin, G.B., (2005) J. Mol. Catal., A: Chem., 227, p. 247Shul'pin, G.B., Nizova, G.V., Kozlov, Y.N., (1996) New J. Chem., 20, p. 1243Shul'pin, G.B., Lachter, E.R., (2003) J. Mol. Catal., A: Chem., 197, p. 65Shul'pin, G.B., Süss-Fink, G., Lindsay Smith, J.R., (1999) Tetrahedron, 55, p. 5345Shul'pin, G.B., Süss-Fink, G., Shul'pina, L.S., (2001) J. Mol. Catal., A: Chem., 170, p. 17Shul'pin, G.B., Nizova, G.V., Kozlov, Y.N., J. Organomet. Chem., , in press