0.0010
300
500
–6
–4
–2
0
2
4
550
600
650
λ (nm)
700 750
800
0
1x10 4
2x10 4
3x10 4
–80
–40
0
40
MeO
MeO
MeO
OMe
(P)–25
25
26
27
(P)–26
(P)–27
(P)–28
Pr
Pr
Pr
Pr
N
N
N
N
H
NO2
NH2
OMe
OMe
BF 4
–
BF4
–
BF4
–
MeO OMe BF 4
–
Δε (L.mol –1
.cm –1
)
Δε (L.mol –1
.cm –1
)
ε (L.mol –1
.cm –1
)
400
500
600
H
CHO
NO 2
NH 2
λ (nm)
700
800
0.0005
0.0000 ΔI
–0.0005
–0.0010
1.0
0.8
0.6
0.4
0.2
0.0
0.0
0.0
638 708 778
Wavelength (nm)
Intensity (arb. units)
0.0010
0.0005
0.0000 ΔI
–0.0005
–0.0010
1.0
0.8
0.6
0.4
0.2
638
568
708 778
Wavelength (nm)
Intensity (arb. units)
0.0010
0.0005
0.0000 ΔI
–0.0005
–0.0010
1.0
0.8
0.6
0.4
0.2
638
568
708 778
Wavelength (nm)
Intensity (arb. units)
+
Pr
Pr
N
N
CHO
+
Pr
Pr
N
N
+
+
Fig. 4.9 Chemical structures of carbocationic diaza[4]helicenes 25–28 and their UV-vis, ECD
and CPL activities. Adapted with permission [29]. Copyright 2016, Royal Society of Chemistry
64
J. Crassous