Mechanism of Dehydro-L-ascorbic Acid Reduction at Mercury Dropping Electrode

Quantitative substantiation of the difference in the intermediate stages of dehydro-L-ascorbic acid polarographic reduction to L-ascorbic acid and of L-ascorbic acid polarographic oxidation to dehydro-L-ascorbic acid is given. It has been established that the first process is described by the C_rE_qrC_i mechanism with the preceding reversible and the following irreversible rate determining chemical stages and with the quasi-reversible transfer of the first electron in two parallel stages with and without participation of proton.