Abstract
Descriptive, low temperature, cyclic voltammetry studies have been conducted upon diethyl fumarate (DEF) in dimethylformamide (DMF). Temperature variations down to 200°K reveal three, interrelated, reduction processes. The first and second correspond to the formation of 
and DEF=; the third is attributed to the reduction of a dimeric product of the initial reduction. Temperature reduction inhibits the formation of this dimeric product while enhancing the availability of 
for reduction to DEF=. The extensive formation of DEF= at reduced temperatures appears to be accompanied by a filming of the electrode surface. This suggests that polymerization may proceed through DEF= and may actually be inhibited by the dimerization process. The addition of water enhances the third reduction peak; it also decreases the available cathodic potential range so that this peak becomes lost in background at room temperature. Temperature reduction increases the available potential range so that products of the water‐accelerated electrohydrodimerization reaction may be studied.