Supporting Information
External Stimulus-Responsive Supramolecular Polymers Constructed by
a Stilbene Cyclodextrin Dimer and Photochemical Switching of
Conformation
Paul Kuad, Atsuhisa Miyawaki, Yoshinori Takashima, Hiroyasu Yamaguchi and Akira
Harada*
Department of Macromolecular Science, Graduate School of Science, Osaka University,
1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
E-mail: [email protected]
Contents
Measurements and Synthesis.
Additional Experiments
Figure S1.
UV-vis spectra of stilbene bis(β-CD) upon successive irradiations.
Figure S2.
AFM images of 1:1 mixture of the stilbene bis(β-CD) and the guest dimer
C3.
Figure S3a.
Mono- and ditopic guest molecules.
Figure S3b.
Definition of K1 and K2 for the stilbene bis(β-CD).
Table S3.
Results from the ITC titration in water at 30 ºC.
Figure S4.
ITC calorimetric titration thermograms.
Figure S5.
Partial 1H-NMR spectra of C3 guest in D2O at 30 ºC in various conditions.
1
Measurements.
1
H NMR spectra were recorded at 400 MHz on a JEOL-GSX 400 spectrometer. 2D 1H
ROESY NMR spectra were recorded at 600 MHz on a VARIAN UNITY plus NMR
spectrometer. Chemical shifts were referenced to the solvent values (δ = 4.70 ppm for HOD,
δ = 2.50 ppm for DMSO-d6). Positive-ion matrix assisted laser desorption/ionization
time-of-flight (MALDI-TOF) mass measurements were performed on a Shimadzu/KRATOS
AXIMA-CFR spectrometer with 2,5-dihydroxy benzoic acid as matrix, and NaCl as
cationizing agent. Preparative reversed-phase chromatography was performed with Waters
Delta 600 system (column: SunFireTM Prep C18 19 × 150 mm).
Determination of diffusion coefficient and hydrodynamic radius. The pulse field
gradient spin-echo (PFGSE) NMR spectra were recorded at 600 MHz in D2O on a VARIAN
UNITY plus NMR spectrometer at 30.0 °C. A WETBPPSTE pulse sequence was applied for
PFGSE NMR measurements, and the pulsed field gradient strength was increased from 0.30
to 25.0 G/cm.1’ For the time separation between pulsed field gradients and their duration were
applied the values of 0.10 and 1.10 x 10-3 s, respectively. According to the Stejskal and
Ranner’s reports,2’ when ln I/I0 vs g2 were plotted, where I and g are the echo intensity and
(pulsed) gradient strength, respectively, the slope of the line given by D/(Δ - δ/3)γ2δ2. Here, δ,
γ, and Δ are the duration, gyromagnetic ratio, and the time separation, respectively, between
the magnetic field gradient pulses. The hydrodynamic radius (Rh) was estimated by eq 1
Rh =
k BT
6πηD
(1)
where η is the viscosity coefficient and kB is the Boltzmann constant.
ITC measurements. ITC experiments were carried out in a MicroCal VP-ITC system
titration calorimeter at 30.00 ± 0.01°C. Experimental titration curves were analyzed with the
Origin LLC ITC 7.0 program. Host (in the calorimeter cell) were always titrated by guest (in
the syringe). Typical concentrations were 0.05 mM and 4 mM, respectively. The guest
solution was injected into the cell in injections of 20 μL, with a 6-min interval between
injections.
Synthesis.
4,4’-stilbene dicaboxylic acid
4-vinylbenzenboic acid (1 g, 6.75 mmol), 4-iodo-benzoic acid (1.67 g, 6.75 mmol),
triphenylphosphine (59 mg, 0.225 mmol), triethylamine (10ml) and palladium (II) acetate
(40 mg) were allowed to react in THF (20 ml) at 80 ºC for 12 hours. After being cooled down
to room temperature, the precipitate was collected by filtration and washed with acetone 3
times and finally dried in vacuum to give the product (250 mg, yield: 14 %). 1H-NMR
(DMSO-d6, 30 ºC, 400 MHz): δ 7.94 (d, 4H, α aromatic H, J = 8.0Hz), 7.73 (d, 4H, β
aromatic H, J = 8.0Hz), 7.94 (s, 2H, stilbene H).
4,4’-stilbene bis ONSu ester
To a solution of stilbene 4,4’-dicarbonylic acid (100 mg, 0.37 mmol) in DMF (20 ml), DCC
(230 mg, 1.1 mmol), and N-hydroxysuccinimide (125 mg, 1.1 mmol) were added at room
temperature. After 24 hours, 1 more equivalent of DCC and N-hydroxysuccinimide was
added and stirred overnight. After the prescribed time the precipitate, dicyclohexylurea, was
removed by centrifugation. The supernatant solution was evaporated to dry and the residue
was recrystallized from about 50 ml of 2-propanol to give a pale white powder (105 mg,
yield = 60.2%). 1H-NMR (DMSO-d6, 30 ºC, 400 MHz): δ 8.12 (d, 4H, α aromatic H,
J = 8.4 Hz), 7.94 (d, 4H, β aromatic H, J = 8.4 Hz), 7.67 (s, 2H, stilbene H), 2.91 (s, 8H, alkyl
H).
2
stilbene bis(β-CD)
4,4’-stilbene bis ONSu ester (100 mg, 0.22 mmol) and 6-NH2-β-CD (2.2 eq) were dissolved
in 20 ml of DMF and stirred at room temperature for 36 hours. After the prescribed time, the
reaction mixture was poured into 300 ml of acetone to precipitate the CD compounds. The
precipitate was collected by centrifugation and further washed with acetone. The crude
product was purified by reverse-phase preparative HPLC eluted with water/acetonitril.
(elution: H2O/MeCN gradient, flow: 15 ml.min-1, 40 ºC) Positive ion MALDI-TOF MS
(m/z): 2523.5 ([M + Na]+=2523.3). 1H-NMR (DMSO-d6, 30 ºC, 600 MHz): δ 8.24 (bs, 2H,
-CO-NH-), 7.84 (d, 4H, phenyl, J = 7.8 Hz), 7.70 (d, 4H, phenyl, J = 7.8 Hz), 7.40 (s, 2H,
stilbene), 5.83-5.47 (m, 28H, O(2)H and O(3)H of β-CD), 4.98-4.76 (m, 14H, C(1)H of
β-CD), 4.54-4.32 (m, 18H, O(6)H and C(6’)H of β-CD), 3.90-3.14 (m, overlaps with HOD),
Elem. anal. calcd for C100H150N2O70•22H2O: C, 41.47; H, 6.74; N, 0.98. Found: C, 41.34; H,
6.48; N, 1.47
References
(1’) (a) Liu, Y.; Li, L.; Fan, Z.; Zhang, H.-Y.; Wu, X.; Guan, X.-D.; Liu, S.-X. Nano Lett. 2002, 2, 257-261. (b) Liu, Y.; Wang, H.; Liang, P.; Zhang,
H.-Y. Angew. Chem., Int. Ed. 2004, 43, 2690-2694.
(2’) Boger, J.; Corcoran, R. J.; Lehn, J.-M. Helv. Chim. Acta. 1978, 61, 2190.
3
a)
0.8
0.6
from 0 to 3 min
abs.
0.4
0.2
0.0
200
250
300
350
400
λ nm
b)
0.8
0.6
abs.
from 0 to 4 min
0.4
0.2
0.0
200
250
300
350
400
λ nm
Figure S1. UV-vis spectra of stilbene bis(β-CD) upon irradiation at 365 nm (a)
and succesive irradiation at 254 nm (b) in aqueous solutions at 1.0 10-5 M at room
temperature.
4
a)
b)
Figure S2. AFM images of 1:1 mixture of the trans (a) and cis (b) stilbene
bis(β-CD) and the guest dimer C3 on mica substrate.
5
Br
Br
N
N
+
+
O
AdCOCH2Py
AdPy
Br
Br
N
+
N
O
+
+
+
Br
O
AdBpyMe
Br
N
N
O
"C3"
Figure S3a. Mono- and ditopic guest molecules.
K1
+
K2
+
Figure S3b. Definition of K1 and K2 for the cyclodextrin dimer.
K (M-1)
trans
cis
Adpy
AdCOCH2Py
AdBpyme
K1
(1.8 ± 0.3) 104
(1.5 ± 0.4) 105
(1.6 ± 0.2) 105
K2
(3.9 ± 0.4) 103
(1.4 ± 0.4) 104
(2.4 ± 0.3) 104
K1
(2.3 ± 0.4) 104
(1.2 ± 0.2) 105
(1.9 ± 0.3) 105
K2
(4.9 ± 0.4) 10
3
(1.5 ± 0.4) 104
(2.7 ± 0.4) 10
4
Table S3. Results from the ITC titrations in water at 30 ºC. Association constant of stilbene bis(β-CD)
with various model compounds.
6
b)
a)
K = 1.45 106 M-1
K = 4.18 105 M-1
Figure S4. ITC calorimetric titration thermograms. Titration of the trans (a) and
cis (b) stilbene bis(β-CD) by the guest dimer C3 in water at 30 ºC.
7
d)
c)
b)
a)
Figure S5. Partial 1H-NMR spectra of C3 guest (pyridinium protons) in D2O at
30 ºC: (a) no addition, (b) with 2 eq. of β-CD, (c) with 1 eq. of cis host isomer, (d)
with 1 eq. of trans host isomer.
8