ELECTROREDUCTION OF 2-ETHYLPICOLINATE, 2-FORMYLPYRIDINE AND PICOLINIC-ACID - A VOLTAMMETRIC STUDY

The reduction of 2-ethylpicolinate (1), 2-formylpyridine (2) and picol inic acid (3) in 0.5 to 5 M H2SO4 solution was studied by voltamperome try on lead electrodes between 15 and 65 degrees C. The running curves show a partial passivation of the cathode; it is assumed that a visco us layer of polymeric products is formed on the surface. Under potenti ostatic conditions the quasi-stationary current increased with the tem perature and acidity. Compounds land 3 show some similarities, while t he difference between the behaviour of compounds 1 and 2 results from the non-reducible hydrated form of 2, which is in equilibrium with its free form. Equilibrium data for 2 were measured by an amperometric te chnique. (C) 1998 Elsevier Science Ltd. All rights reserved.