Mendeleev Commun., 2010, 20, 207–208
Table 1 Electrocatalytic dimerization of diphenylacetonitrile 1a.a
Thus, the new highly efficient electrocatalytic method was
found, namely, the preparation of tetraarylsuccinonitriles from
diarylacetonitriles in 80–100% yields in an undivided cell in
the presence of sodium halides as mediators instead of using
large quantities of expensive oxidants.
The process requires the use of a commercially available
mediator and inexpensive apparatus. The techniques for elec-
trolysis and isolation of the reaction products are simple and con-
venient to use both under laboratory conditions and in large-scale
apparatus. Therefore, this electrocatalytic method brings us a step
closer to the notion of green chemistry and ideal synthesis.28
Electricity
Time/
min
Yield of
Entry Solvent
Electrolyte
NaBr
passed/
2a (%)b
F mol–1
1
2
3
4
MeOH
32
32
42
42
1
1
1.3
1.3
73
80
100
95
MeOH–THF, 3:1 NaBr
MeOH–THF, 3:1 NaBr
MeOH–THF, 3:1 NaI
a1a (5 mmol), mediator (2 mmol), solvent (10 ml), iron cathode (2.5 cm2)
graphite anode (2.5 cm2), current density, 100 mA cm–2, 20 °C. bIsolated
yield.
Table 2 Electrocatalytic dimerization of DAAs 1a–g.a
This work was supported by the Presidential Scholarship
Programme for State Support of Leading Science Schools of
the Russian Federation (project no. 4945.2010.3).
Electricity
Product,
Entry Substrate R1
R2
Electrolyte passed/
F mol–1
yield (%)b
Online Supplementary Materials
Supplementary data associated with this article can be found
in the online version at doi:10.1016/j.mencom.2010.06.008.
1
2
3
4
5
6
7
8
9
1a
1b
1c
1d
1e
1f
1g
1g
1g
H
Me
Cl
Br
I
Me
MeO
MeO
MeO
H
H
H
H
H
NaBr
NaBr
NaBr
NaBr
NaBr
1.3
1.3
1.3
1.3
1.3
1.3
1.3
1.3
5
2a, 100
2b, 95
2c, 97
2d, 93
2e, 89
2f, 87
2g, 81
3, 53c
3, 88
References
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2
3
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,
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Scheme 2
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Ph
Ar
Ph
Ar
Hal2
– Hal–
CN + MeO–
CN
1
A
Ph
Hal
Ar
Ph
Ph
CN
Ar
A
CN
NC
Ar
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4
2
Scheme 3
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Compound 1g, having an electron-donating substituent in a
phenyl ring (4-MeO group), in the presence of sodium bromide
as a mediator, was oxidized directly at the anode with the forma-
tion of 1g cation. The following methoxylation of 1g cation
afforded diaryl(methoxy)acetonitrile 3.
Received: 12th February 2010; Com. 10/3466
– 208 –