anti orientation isomer [18]. Both of them showed one singlet for the tert-butyl
protons, one singlet for the methoxy protons and two singlets for the bridgehead
protons of the triptycene moiety in the
1 H NMR spectra, while there was only one
signal for the methylene carbons in their
13 C NMR spectra. Moreover, there were no
obvious changes in the methylene proton signals with increasing temperature in their
variable-temperature
1 H NMR spectra. These observations suggested that both 4a
and 5a have highly symmetric structures and fixed conformations. However, their
1
H
NMR spectra showed a large difference from each other. For the methylene protons,
a pair of doublet signals at 3.35 and 4.25 ppm (Δδ = 0.90) were observed in 4a,
whereas 5a showed a pair of doublet signals at 3.67 and 3.86 ppm with a Δδ value of
about 0.19 ppm. This result implied that macrocycles 4a and 5a are a pair of
diastereomers, 4a has a syn orientation of the two triptycene moieties, while 5a is
an anti orientation isomer. Similarly, 4b and 5b, 7a–c and 8a–c, 11a–d and 12a–d,
13, and 14 are also diastereomers with symmetric structures and fixed
HN
HN
N
H
NH
HN
HN
N
H
NH
44a R = H, 27%; 45a R = OMe, 20%
N
N
N
N
N
N
N
N
N
N
N
N
NH 2
NH 2
R
R
1c R = H
43 R = OMe
DIPEA
THF, r.t.
Cl
Cl
Cl
Cl
44b R = H,16%; 45b R = OMe, 18%
HN
HN
N
H
NH
HN
HN
N
H
NH
46a R = H, 19%; 47a R = OMe, 16%
46b R = H, 8%; 47b R = OMe, 9%
R
R
R
R
R
R
R
R
DIPEA
THF, reflux
R
R
O 2 N
NO 2
O 2 N
NO 2
R
R
O 2 N
NO 2
O 2 N
NO 2
R
R
R
R
+
+
N
N
N
Cl
Cl
Cl
O 2 N
NO 2
F
F
NH
N
H
N
N
N
N
N
N
Cl
Cl
R
R
Cl
Cl
DIPEA
CH 3 CN, r.t.
44a R = H 45%
45a R = OMe 34%
F
R
R
O 2 N
NO 2
F
NO 2
O 2 N
HN
N
H
46a R = H 26%
47a R = OMe 24%
DIPEA
THF, r.t.
DIPEA
THF, reflux
N
N
N
Cl
Cl
Cl
O 2 N
NO 2
F
F
43
DIPEA
CH3CN, r.t.
43
48a R = H, 87%; 49a R = OMe, 81%
48b R = H, 84%; 49b R = OMe, 79%
44b R = H 34%
45b R = OMe 27%
+
46b R = H 19%
47b R = OMe 11%
+
Scheme 9 Synthesis of triptycene-derived N(H)-bridged azacalixarenes 44–47
6 Triptycene-Derived Macrocyclic Arenes
151
protons, one singlet for the methoxy protons and two singlets for the bridgehead
protons of the triptycene moiety in the
1 H NMR spectra, while there was only one
signal for the methylene carbons in their
13 C NMR spectra. Moreover, there were no
obvious changes in the methylene proton signals with increasing temperature in their
variable-temperature
1 H NMR spectra. These observations suggested that both 4a
and 5a have highly symmetric structures and fixed conformations. However, their
1
H
NMR spectra showed a large difference from each other. For the methylene protons,
a pair of doublet signals at 3.35 and 4.25 ppm (Δδ = 0.90) were observed in 4a,
whereas 5a showed a pair of doublet signals at 3.67 and 3.86 ppm with a Δδ value of
about 0.19 ppm. This result implied that macrocycles 4a and 5a are a pair of
diastereomers, 4a has a syn orientation of the two triptycene moieties, while 5a is
an anti orientation isomer. Similarly, 4b and 5b, 7a–c and 8a–c, 11a–d and 12a–d,
13, and 14 are also diastereomers with symmetric structures and fixed
HN
HN
N
H
NH
HN
HN
N
H
NH
44a R = H, 27%; 45a R = OMe, 20%
N
N
N
N
N
N
N
N
N
N
N
N
NH 2
NH 2
R
R
1c R = H
43 R = OMe
DIPEA
THF, r.t.
Cl
Cl
Cl
Cl
44b R = H,16%; 45b R = OMe, 18%
HN
HN
N
H
NH
HN
HN
N
H
NH
46a R = H, 19%; 47a R = OMe, 16%
46b R = H, 8%; 47b R = OMe, 9%
R
R
R
R
R
R
R
R
DIPEA
THF, reflux
R
R
O 2 N
NO 2
O 2 N
NO 2
R
R
O 2 N
NO 2
O 2 N
NO 2
R
R
R
R
+
+
N
N
N
Cl
Cl
Cl
O 2 N
NO 2
F
F
NH
N
H
N
N
N
N
N
N
Cl
Cl
R
R
Cl
Cl
DIPEA
CH 3 CN, r.t.
44a R = H 45%
45a R = OMe 34%
F
R
R
O 2 N
NO 2
F
NO 2
O 2 N
HN
N
H
46a R = H 26%
47a R = OMe 24%
DIPEA
THF, r.t.
DIPEA
THF, reflux
N
N
N
Cl
Cl
Cl
O 2 N
NO 2
F
F
43
DIPEA
CH3CN, r.t.
43
48a R = H, 87%; 49a R = OMe, 81%
48b R = H, 84%; 49b R = OMe, 79%
44b R = H 34%
45b R = OMe 27%
+
46b R = H 19%
47b R = OMe 11%
+
Scheme 9 Synthesis of triptycene-derived N(H)-bridged azacalixarenes 44–47
6 Triptycene-Derived Macrocyclic Arenes
151