F. Yang et al. / Tetrahedron Letters 53 (2012) 1598–1602
1601
Table 1
phenylene column with calixarene units on ancillary lateral sides
for the first time. The studies on complexation property and its influ-
ences on mesomorphic property will be studied and reported in due
course.
Transition temperatures (peak temperature/°C) and associated enthalpy changes (kJ/
mol in parentheses) of 4 and 7
Triads
4
Phase transitiona
T(
D
H) Heating scan
T(DH) Cooling scan
Cr–Col1
39.47(14.4)
48.64(0.49)
72.96(2.14)
34.13(41.0)
46.64(0.40)
66.80(2.24)
37.26(3.84)
51.60(1.67)
65.60(0.89)
30.0(2.46)
35.18(10.1)
51.93(19.5)
Col1–Col2
Col2–Iso
Cr–Col1
Col1–Col2
Col2–Iso
Acknowledgments
7
Financial support from the National Natural Science Foundation
of China (No: 20402002), Fujian Natural Science Foundation of Chi-
na (No. 2011J01031), Project of Fujian Provincial Department of
Education (JA11044) and Program for Excellent young researchers
in University of Fujian Province (JA10056) were greatly acknowl-
edged. Thanks to Professor Lei Zhu for the direction on synthesis
of triphenylene.
a
Cr = crystalline, Col = columnar, Iso = isotropic.
that mesophase existed on melting process with state-meso-
phase(Col1 and Col2 phase)-isotropic phase on heating. Further,
based on the DSC results, the phase textures of mesophase of com-
pounds 4 and 7 were investigated under polarized optical micros-
copy as shown in Figure 1. The clear columnar-shaped textures
were observed. These textures were similar to the known textures
for columnar phase of triphenylene derivatives.32–36
Supplementary data
Supplementary data associated with this article can be found, in
The molecular stacking behavior of compound 4 was also stud-
ied by AFM in tapping mode as shown in Figure 2. The plump
stripes in the image represented the columnar structure. This re-
sult demonstrated that triad 4 possessed highly ordered columnar
phase, which was in accordance with the previous reports of tri-
phenylene columnar phases.32–37
References and notes
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ther, triads 4 and 7 were studied by the XRD. The results were
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29. Compound 4: 1H NMR (400 MHz, CDCl3) d ppm: 0.97 (t, 30H, J = 7.2 Hz, CH3),
1.07 (s, 18H, C(CH3)3), 1.28 (s, 18H, C(CH3)3),1.42–1.96 (m, 76H, CH2), 3.49 (d,
4H, J = 13.6 Hz, ArCH2Ar), 3.96 (t, 4H, J = 6.4 Hz, OCH2), 4.23 (m, 28H, TpOCH2
and ArCH2Ar), 4.60 (s, 4H, OCH2), 6.74 (d, 4H, J = 9.2 Hz, ArH), 6.98 (s, 4H, ArH),
7.12 (s, 4H, ArH), 7.33 (d, 4H, J = 9.2 Hz, ArH), 7.83 (s, 12H, ArH), 8.05 (s, 2H,
NH), 10.13 (s, 2H, OH); 13C NMR (150 MHz, CDCl3) d ppm: 14.149, 22.601,
23.646, 26.558, 28.435, 29.175, 29.726, 31.093, 31.254, 31.535, 31.725, 31.952,
33.865, 34.037, 66.610, 68.843, 68.910, 69.010, 69.289, 69.559, 69.879, 73.688,
107.008, 107.108, 107.390, 107.471, 107.671, 107.740, 108.414, 114.924,
122.996, 123.115, 125.735, 127.810, 129.543, 132.888, 141.490, 146.227,
147.189, 148.096, 148.747, 148.908, 149.035, 149.116, 149.256, 149.320,
149.439, 149.511, 149.649, 150.641, 160.765; IR/cmÀ1: 3436, 2955, 2926,
1682, 1615, 1510, 1433, 1262, 1169, 1040, 832; UV–vis: 278 nm. MS m/z (%):