Organic Electrode Reactions - Fundamentals and Applications of Organic Electrochemistry - page 121

selectively by the choice of appropriate
mediator.
(5.3)
5.1.2.2 Electrosynthesis Using Halogen
Mediators
Anodic oxidation of halide ions (X − ) generates
various kinds of reactive cationic species, for
example X + , OX − , X 2 , X 3 − etc., which are
widely utilized as mediators for various
oxidative molecular conversions, as shown in
Figure 5.1 . Oxidative power increases in the
order I < Br < Cl, and positive Cl is too strong
oxidant to give good selectivity. Iodide and
bromide ions are therefore mainly employed as
mediators for selective indirect oxidation. The
synthetic applications of such electrogenerated
active halogen species as mediators have been
demonstrated by highly selective
functionalization of olefins, e.g. epoxidation,
halohydroxylation, 1,2-dihalogenation and
ene-type chlorination, heteroatom-heteroatom