2-Cyano-1-methylpyridinium ion [4415-72-9] exhibits 3 well-defined polarog. waves in Britton-Robinson buffers at pH 5 to 8. Electrolysis at the plateau potential of the most pos. wave, involving a 1-electron uptake, leads to the formation of a pyridinyl radical which probably dimerizes to a 2,4'-linked structure. Electrolysis at the plateau potential of the 2nd-wave, involving a no. ofelectrons variable between nearly 4 (at pH .apprx.5) and .apprx.3 (at pH .apprx.8), leads to the formation of a mixt. of 2-aminomethyl-1-methylpyridinium ion and 1-methylpyridinium ion. At the 3rd wave potentials the 2nd wave products are further reduced to give basic species with catalytic activity.