Y. Wu et al. / Tetrahedron 76 (2020) 131549
5
using petroleum ether:ethyl acetate ¼ 30:1 to 20:1 as eluent to
obtain compound 4 as a white solid powder (6.02 g, yield 64.3%). 1H
NMR (600 MHz, CDCl3, 298 K)
d
(ppm): 6.91 (d, J ¼ 6 Hz, 8H), 6.61
(d, J ¼ 6 Hz, 8H), 3.92 (t, J ¼ 6 Hz, 8H), 3.47 (t, J ¼ 6 Hz, 8H), 2.05 (m,
8H), 1.90 (m, 8H).
4.3.5. Synthesis of compound 5
Under the protection of argon, compound 1 (3.29 g, 14.4 mmol)
and K2CO3 (7.95 g, 57.6 mmol) were mixed in 500 mL of CH3CN in a
three-neck flask. The mixture was stirred and refluxed in the three-
neck flask. Then, compound 4 (1.69 g, 1.80 mmol) in 100 mL CH3CN
was injected slowly. After 2 days, the mixture was filtered and the
filtrate was concentrated under vacuum. The residue was purified
by column chromatography using CH2Cl2:methanol ¼ 20:1 as
eluent to obtain compound 5 as an orange solid powder (420 mg,
yield 15.3%). 1H NMR (600 MHz, DMSO-d6, 298 K)
d (ppm): 7.84 (d,
J ¼ 6 Hz, 8H), 7.78 (d, J ¼ 6 Hz, 8H), 7.47 (d, J ¼ 6 Hz, 8H), 7.07 (d,
J ¼ 12 Hz, 8H), 6.81 (d, J ¼ 6 Hz, 8H), 6.67 (d, J ¼ 6 Hz, 8H), 5.33 (s,
4H), 4.56 (s, 8H), 4.08 (t, J ¼ 12 Hz, 8H), 3.93 (t, J ¼ 12 Hz, 8H), 1.83
(m, 16H). 13C NMR (151 MHz, DMSO-d6, 298 K)
d (ppm): 164.4,
160.0, 154.1, 149.3, 148.6, 139.3, 135.2, 135.1, 135.0, 130.2, 127.5,
125.2, 118.1, 116.9, 70.9, 70.0, 65.9, 42.5, 32.6, 28.4. HRMS: m/z calcd
for [M þ 2K þ 2H]4þ, C94H94N8O12K42þ, 401.0834, found 401.0832,
error ꢀ1 ppm.
4.3.6. Synthesis of compound 6
To a solution of compound 5 (130 mg, 85.0 mmol) in 50.0 mL of
dried CH2Cl2 was added PBr3 (65.0
m
L, 0.680 mmol) at ꢀ50 ꢁC. The
resulting mixture was stirred for 5 min at ꢀ50 ꢁC and then 1 h at
room temperature. After quenched by water, the organic layer was
separated and concentrated to obtain 6 (135 mg, yield 89.4%) as an
orange solid, which was used in the next step without further
purification. 1H NMR (600 MHz, CDCl3, 298 K)
d (ppm): 7.89 (d,
J ¼ 6 Hz, 8H), 7.84 (d, J ¼ 6 Hz, 8H), 7.51 (d, J ¼ 6 Hz, 8H), 6.98 (d,
J ¼ 6 Hz, 8H), 6.93 (d, J ¼ 6 Hz, 8H), 6.64 (d, J ¼ 6 Hz, 8H), 4.54 (s,
8H), 4.10 (t, J ¼ 6 Hz, 8H), 3.97 (t, J ¼ 6 Hz, 8H), 1.81 (m, 16H). 13
C
NMR (151 MHz, CDCl3, 298 K)
d (ppm): 164.4, 155.2, 149.8, 142.8,
135.2, 132.5, 127.8, 125.7, 117.4, 116.2, 70.7, 70.0, 35.6, 125.6, 32.3,
28.6, 25.3, 16.6, 3.7, 2.6. MALDI-TOF MS: m/z calcd for [M þ H]þ
C94H89N8O8Brþ4 , 1777.0185, found 1777.0160.
Declaration of competing interest
Scheme 2. Synthetic procedures of the TPE-bearing guest molecule.
The authors declare that they have no competing financial in-
terests or personal relationships that could have appeared to in-
fluence the work reported in this paper.
4.3.3. Synthesis of compound 3
Compound 3 was prepared according to the previous report.
[37b] BBr3 (3.80 mL, 40.0 mmol) was added to a cooled solution of
compound 2 (4.53 g, 10.0 mmol) in CHCl3 (200 mL) at 0 ꢁC and the
resulting deep red mixture was stirred for 2 h at. After removal of
the cooling bath, the mixture was stirred for 10 h at room tem-
perature and then quenched by water. The precipitate was filtered,
washed with H2O and CH2Cl2. Recrystallization from EtOH/H2O
(1:1) obtained 3.29 g (yield 82.3%) of a light pink solid. 1H NMR
Acknowledgments
This work was supported by the Fundamental Research Funds
for the Central Universities.
Appendix A. Supplementary data
(400 MHz, DMSO-d6, 298 K)
8H), 6.47 (d, J ¼ 12 Hz, 8H).
d
(ppm): 9.22 (s, 4H), 6.70 (d, J ¼ 8 Hz,
Supplementary data to this article can be found online at
4.3.4. Synthesis of compound 4
Supplementary Material
Compound 4 was prepared according to the previous report
[38c]. Under the protection of argon, 1,4-dibromobutane (23.9 mL,
200 mmol) and K2CO3 (22.1 g, 160 mmol) were mixed and refluxed
in 500 mL of CH3CN in a three-neck flask. Compound 3 (3.96 g,
10.0 mmol) in 100 mL of CH3CN was injected slowly. After 2 days,
the mixture was filtered and the filtrate was concentrated under
vacuum. The residue was purified by column chromatography
1H and 13C NMR spectra, mass spectra, and other materials.
Supplementary data related to this article can be found at http://xx.
References