F. Bureš et al. / Tetrahedron Letters 51 (2010) 2055–2058
2057
Table 1
Structure, yields, melting points, optical and electrochemical properties of chromophores 1–6
b
b
Chromophore
1
R
Yielda (%)
89
Mp (°C)
kmax (nm (eV))
Color
Epc (V)
Epa (V)
Epa À Epc (V)
2.80
See Scheme 1
218–219
349 (3.55)
Yellow
À1.96
À1.45
+0.84
+0.90
2
3
96
84
238–240
206–208
429 (2.90)
416 (2.98)
Orange
2.35
Orange–red
À1.23
À1.19
À1.16
+0.87
+0.65
+0.94
2.10
1.84
2.10
4
5
78
74
222–225
126–128
437 (2.84)
407 (3.05)
Red
Red
6
81
183–185
450 (2.76)
Dark red
À1.25
+0.75
2.00
a
Isolated yield of the final cross-coupling step.
Epc, Epa—cathodic (anodic) peak potentials measured by CV. All potentials are given versus SCE.
b
Acknowledgements
This research was supported by the Czech Science Foundation
(203/08/0076) and the Ministry of Education, Youth and Sport of
the Czech Republic (MSM 0021627501). J.L. thanks the Structural
Funds, Interreg IIIA, for financial support in purchasing the
diffractometer.
Supplementary data
Supplementary data associated with this article can be found, in
References and notes
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