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distilled over calcium hydride prior to use. Dichloromethane (DCM)
was refluxed with calcium hydride and distilled prior to use. Other
solvents were used as received. Reactions were monitored by thin-
layer chromatography (TLC) plates. Visualization of the developed
plates was performed under UV light (254 nm and 365 nm).
Column chromatography was performed with silica gel (100–200
mesh) using glass columns. 1H NMR spectra were recorded on
a Bruker Av400 NMR spectrometer at 400 MHz. 13C NMR spectra
were recorded on a Bruker Av500 NMR spectrometer at 126 MHz.
Chemical shifts are given in parts per million (ppm) relative to tet-
ramethylsilane (TMS). High-resolution mass spectra (HRMS) were
recorded on a Waters GC-TOF and LC/Q-TOF mass spectrometer.
All the new compounds were characterized by 1H NMR, 13C NMR
spectroscopy and HRMS. For known compounds, we have cited
the reported characterization data that we used to compare to our
synthesized compounds and we have provided a 1H NMR spectrum
to confirm the purity of the isolated material. Fluorescence spectra
were obtained from a Jasco FP-8300 spectrofluorometer. UV/Vis
absorption spectra were all taken on a Hitachi UV-4100 spectro-
photometer. Quartz cells with 1 cm path length were used. Meas-
urements of the specific viscosities as a function of concentration
were conducted using an Ubbelohde micro-dilution viscometer at
258C. To ensure the accuracy, each sample was measured for 5
times to calculate the average flowing time. Dynamic light-scatter-
ing (DLS) tests were carried out on a Malvern Zetasizer Nano ZSP
and the solutions were filtered through a Teflon filter (pore size:
0.2 mm) before tests. SEM studies were carried out on a FEI
Quanta 450 electron microscopy operated at 20 kV. The sample for
SEM was prepared by dropcasting the solution to a freshly pre-
pared silicon wafer and then dried in the ambient environment
naturally. After that, the sample was sputtered with gold and sub-
mitted to the microscopy. TEM studies were run on a FEI Tecnai 20
electron microscopy at 200 kv. The sample for TEM was prepared
by dropcasting the solution to a carbon-coated copper grid and
dried in the ambient environment. Then the sample was submitted
to the microscopy.
127.52, 127.47, 124.77, 124.32, 123.85, 121.38, 118.65, 114.31,
55.38 ppm; TOF-LD-MS calcd for C67H47N6O: 951.3811 [M+H]+;
found: 951.3788.
Synthesis of compound 4: Under N2 atmosphere, compound 3
(0.475 g, 0.5 mmol) was dissolved in dry DCM (30 mL). Then the so-
lution was cooled to À788C and BBr3 (0.46 mL, 3 mmol) was added
in one portion. The solution turned brown immediately and was al-
lowed to obtain room temperature overnight, then quenched
slowly with a few drops of water until no gas was observed. The
precipitate was filtered and washed with DCM and CH3OH repeat-
edly, which gave 4 (0.42 g, 89.7%) as a yellow powder. 1H NMR
(400 MHz, [D6]DMSO): d=8.98 (d, J=8.1 Hz, 4H), 8.94–8.91 (m,
8H), 8.36 (t, J=7.8 Hz, 4H), 8.19 (d, J=8.3 Hz, 4H), 8.08–8.02 (m,
9H), 7.97–7.92 (m, 6H), 7.82–7.78 (m, 4H), 7.75 (d, J=8.5 Hz, 2H),
6.94 ppm (d, J=8.7 Hz, 2H); 13C NMR (126 MHz, [D6]DMSO): d=
152.10, 152.05, 152.03, 150.85, 150.84, 150.82, 150.78, 150.15,
150.13, 146.40, 146.39, 146.35, 146.31, 142.28, 142.27, 142.25,
142.23, 142.22, 142.21, 142.19, 141.22, 139.86, 138.27, 135.22,
135.20, 128.27, 127.97, 127.87, 127.84, 127.80, 127.57, 127.56,
127.54, 127.30, 126.32, 126.31, 123.43, 120.16, 115.76 ppm; TOF-LD-
MS calcd for C66H45N6O: 937.3655 [M+H]+; found: 937.3638.
Synthesis of 1,4-bis(4-bromobutoxy)benzene: 1,4-Bis(4-bromobu-
toxy)benzene was synthesized similarly according to a previously
published procedure.[27] 1H NMR (400 MHz, CDCl3): d=6.83 (s, 4H),
3.96 (t, J=6.1 Hz, 4H), 3.51 (t, J=6.7 Hz, 4H), 2.13–2.04 (m, 4H),
1
1.94 ppm (dt, J=12.6, 6.2 Hz, 4H). The H NMR data are in agree-
ment with those found in the literature.
Synthesis of copillar[5]arene: To a 250 mL three-neck round
bottom
flask,
1,4-bis(4-bromobutoxy)benzene
(1.564 g,
4.116 mmol), 1,4-dimethoxybenzene (5.687 g, 41.16 mmol) and par-
aformaldehyde (3.391 g, 113.045 mmol) were added. Then, 1,2-di-
chloroethane (100 mL) was added and the solution was degassed
with N2 for 10 min. Boron trifluoride diethyl etherate (5.7 mL,
45.22 mmol) was injected into the flask under N2 atmosphere and
the mixture was stirred at room temperature. After 30 min, metha-
nol (60 mL) was added to quench the reaction. The solvent was
evaporated under vacuum and the residue was dissolved in DCM
(50 mL) and washed with saturated NaHCO3 aqueous solution for
three times. After that, the organic phase was dried over anhy-
drous MgSO4 and crude product was obtained as a white powder.
Recrystallization from a mixture of ethanol and DCM (3:1, v: v)
Compound 1 and 2 were prepared according to our previously re-
ported method.[26]
Synthesis of 4’-(4-boronatophenyl)-2,2’:6’,2“-terpyridine: 4’-(4-
Boronatophenyl)-2,2’:6’,2”-terpyridine was synthesized according to
a previously reported method.[19] 1H NMR (400 MHz, CD3OD): d=
8.71–8.58 (m, 6H), 8.00 (td, J=7.8, 1.6 Hz, 2H), 7.83–7.68 (m, 4H),
7.50–7.45 ppm (m, 2H).The 1H NMR data are in agreement with
those found in the literature.
1
gave pure copillar[5]arene (1.3 g, 32.3%) as white crystals. H NMR
(400 MHz, CDCl3): d=6.81 (s, 2H), 6.79 (d, J=3.5 Hz, 4H), 6.76 (s,
2H), 6.72 (s, 2H), 3.84–3.75 (m, 14H), 3.70–3.63 (m, 24H), 3.21 (s,
4H), 1.78 ppm (d, J=18.6 Hz, 8H); 13C NMR (126 MHz, CDCl3): d=
150.67, 150.61, 150.55, 150.43, 149.71, 128.42, 128.26, 128.24,
128.13, 128.05, 114.63, 113.97, 113.96, 113.70, 113.49, 67.23, 55.91,
55.70, 55.64, 33.38, 29.65, 29.35, 29.14, 28.32 ppm; TOF-LD-MS
calcd for C51H60O10Br2: 990.2553 [M]+; found: 990.2544.
Synthesis of compound 3: To a 250 mL round bottom flask, 2
(0.492 g,
1 mmol),
4’-(4-boronatophenyl)-2,2’:6’,2“-terpyridine
(0.847 g, 2.4 mmol) and K2CO3 (10 mmol, 1.382 g) were suspended
in a mixture of dioxane (60 mL) and water (20 mL). After bubbling
with N2 for 10 min, [Pd(PPh3)4] (0.04 mmol, 46.24 mg) was added
immediately. The mixture was heated at 888C under N2 atmos-
phere for 36 h. After cooling to room temperature, the solvent was
evaporated and DCM (100 mL) was added. The red solution was
washed three times with water and the organic phase was collect-
ed and dried over anhydrous MgSO4. After the solvent was evapo-
rated in vacuum, compound 3 (0.55 g, 58%) was obtained as
a white powder after purification by column chromatography with
Synthesis of host molecule: Copillar[5]arene (59.4 mg, 0.06 mmol),
compound 4 (56.2 mg, 0.06 mmol), K2CO3 (82.9 mg, 0.6 mmol) and
a catalytic amount of KI (5 mg) were placed in a 100 mL round
bottom flask. Dry CH3CN (50 mL) were added and the suspension
was heated at reflux at 828C under N2 atmosphere for 3 days. After
cooling to room temperature, the pale precipitate was filtered off
and washed with deionized water and CH3CN repeatedly. After
drying in vacuum, host was obtained as a white powder which
was used without further purification. 1H NMR (400 MHz, CDCl3):
d=8.81 (s, 8H), 8.76 (d, J=3.9 Hz, 8H), 8.70 (d, J=8.1 Hz, 8H), 8.02
(d, J=8.2 Hz, 8H), 7.88 (dd, J=23.4, 15.9 Hz, 39H), 7.65 (d, J=
7.3 Hz, 4H), 7.40–7.35 (m, 8H), 7.01 (d, J=9.1 Hz, 4H), 6.88–6.67
(m, 10H), 4.26–3.52 (m, 42H), 2.04 ppm (s, 8H); 13C NMR (126 MHz,
[D8]THF): d=155.89, 154.27, 154.20, 148.56, 147.52, 147.21, 139.80,
a
mixture eluent of DCM and CH3OH (100:1, v/v). 1H NMR
(400 MHz, CDCl3): d=8.87 (s, 4H), 8.78 (d, J=4.0 Hz, 4H), 8.73 (d,
J=7.9 Hz, 4H), 8.08 (d, J=8.3 Hz, 4H), 7.94 (t, J=7.0 Hz, 4H), 7.88–
7.81 (m, 15H), 7.72–7.66 (m, 2H), 7.41 (dd, J=6.8, 5.2 Hz, 4H), 7.06
(d, J=8.8 Hz, 2H), 3.90 ppm (s, 3H); 13C NMR (126 MHz, CDCl3): d=
159.38, 156.17, 155.89, 149.64, 149.09, 142.06, 141.76, 141.18,
140.38, 139.49, 137.29, 136.90, 133.53, 128.40, 127.78, 127.76,
Chem. Eur. J. 2016, 22, 6881 – 6890
6888
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