Organic Electrode Reactions - Fundamentals and Applications of Organic Electrochemistry - page 149

another example [55]. The
trifluoromethylation of fumaronitrile
requires both anodic and cathodic reactions,
hence this reaction is a kind of paired
electrosynthesis.
Linear paired electrosynthesis
(electrosynthesis of single product
through anodic oxidation followed by
cathodic reduction or vice versa): As
shown in Eq. 5.17 , oxidation of
2,3-butandiol provides acetoin, and
afterwards acetoin is reduced at an Hg/Zn
cathode to ethyl methyl ketone [56]. The use
of an undivided cell is essential in this case.
(5.17)
Paired electrosynthesis using EGB
regenerated at the anode and cathode
successively or vice versa: Figure 5.13
illustrates an example of this kind of paired
electrosynthesis. An azobenzene is reduced
to give the corresponding dianion (EGB),
which then reacts with a mixture of ethyl
acetate and butyl bromide as the starting
substrate to give the final product (ethyl
α-(acetyl)hexanoate) and EGBH 2 . The
EGBH 2 is oxidized at the anode to
regenerate the EGB [57].