Siberian Federal University

The effect of the alkaline environment on the oxidation of glucose into gluconic acid (gluconate ion) without the participation of a catalyst was studied by the density functional theory. It has been shown that the solvation environment destabilizes the intermediates of the reaction and, first of all, the glucose diolate R-CHO(OH)‾, the formation of which becomes unlikely. As a consequence, under real catalytic conditions, glucose diolate should be formed on the surface of the catalyst. Destabilization of intermediates, as well as an increase in the energy difference between the triplet and singlet states of the R-CHO(OH)‾… O2 complex in the solution enhances the activation barrier in an alkaline environment to 140 kJ/mol (101 kJ/mol in the gas phase). Of the two main factors, glucose diolate instability and high activation barrier, the first of them plays a decisive role in preventing the reaction from taking place in solution