Supporting Information
Conjugated Microporous Polymers as Molecular Sensing Devices: Microporous Architecture Enables Rapid Response and Enhances Sensitivity in Fluorescence-On and Fluorescence-Off Sensing Xiaoming Liu, Yanhong Xu, and Donglin Jiang
Corresponding Author: Professor Donglin Jiang Department of Materials Molecular Science, Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan. Tel./Fax: +81-564-59-5520 E-mail:
[email protected] Section 1 Method and Materials Section 2 Infrared Spectra Section 3 NMR Spectra Section 4 XRD Pattern Section 5 Fluorescence Spectra Section 6 Vapor Pressure and Redox Potential of Arenes Section 7 Diagram of Fluorescence-on and -off Sensing of Arenes Section 8 Supporting References
Section 1 Method and Materials Bis(1,5-cyclooctadiene)nickel(0) and anhydrous N,N-dimethylformamide (DMF, 99.0%) were purchased from Aldrich Chemicals. 1,5-Cyclooctadiene and 2,2′-bipyridyl were purchased from TCI. Acetic acid, methanol, tetrahydrofunan, acetonitrile, and acetone were purchased from Wako Chemicals. Chloroform and calcium hydride were purchased from Kanto Co. All the S1
arenes were purchased from nacalai tesque and used as received. TCB monomer (3,8,13-tribromo-5,10,15-triethyltriindole) was synthesized by the reported method.[S1] 1
H NMR spectra were recorded on a JEOL model JNM-LA400 NMR spectrometer, where
the chemical shifts (δ in ppm) were determined with a residual proton of the solvent as standard. Solid-state 13C CP/MAS NMR measurements were performed on a JEOL model 920 MHz NMR spectrometer at a MAS rate of 15 kHz and a CP contact time of 2 ms. Fourier transform infrared (FT-IR) spectra were recorded on a JASCO model FT-IR-6100 infrared spectrometer. UV-Vis-IR diffuse reflectance spectrum (Kubelka-Munk spectrum) was recorded on a JASCO model V-670 spectrometer equipped with integration sphere model IJN-727. Photoluminescence spectrum was recorded on a JASCO model FP-6600 spectrofluorometer. Field-emission scanning electron microscopy (FE-SEM) was performed on a JEOL model JSM-6700 operating at an accelerating voltage of 5.0 kV. The sample was prepared by drop-casting a THF suspension onto mica substrate and then coated with gold. High-resolution transmission electron microscopy (HR-TEM) images were obtained on a JEOL model JEM-3200 microscopy. The sample was prepared by drop-casting a THF suspension of TCB-CMP onto a copper grid. X-ray diffraction (XRD) data were recorded on a Rigaku model RINT Ultima III diffractometer by depositing powder on glass substrate, from 2θ = 1.5° up to 60° with 0.02° increment. Electrochemical measurements were carried out in a three-electrode cell, with the ITO electrode as working electrode, a platinum wire as counter electrode and an Ag/Ag+ electrode reference electrode with ferrocenium–ferrocene (Fc+/Fc) as an internal standard. Cyclic voltammetry was carried out at a scan rate of 100 mV/s in acetonitrile containing 0.1 M Bu4NPF6 as supporting electrolyte. The TCB-CMP samples were coated onto the ITO electrode. Nitrogen sorption isotherms were measured at 77 K with a Bel Japan Inc. model BELSORP-mini II analyzer. Before measurement, the samples were degassed in vacuum at 150 °C for more than 10 h. The Brunauer-Emmett-Teller (BET) method was utilized to calculate the specific surface areas and pore volume. The Saito-Foley (SF) method was applied for the estimation of pore size and pore size distribution. Preparation of thin layer sample for sensing. Quartz slides of were first rinsed with de-ionized water and ethanol and dried in an oven. Black scotch tape was then attached to the low half of the slide. For making the thin layer of the CMP sample, the tap was peered off and the slides were covered with the glue from the tap. The ground powder of samples was then sprinkled evenly onto the glue surface of the slide. The extra samples were removed gentle tapping of the slide with the glued face down. By this process, a very thin continuous sample layer with same sample weight and thickness formed on the quartz surface. The slides were then mounted to a sample holder for fluorescence measurements. S2
Detection of arenes. For the liquid arenes, 1 mL of arene was placed in an open glass vial (10 mL) that was placed in a capped glass vial (50 mL) for a week to ensure that the equilibrated vapor pressure of arenes was reached. For solid arene (DNT), 100 mg was utilized and set in the same set-up for liquid arenes. The slides were put into the 50 mL vial for a designated period for exposure to the vapors and were taken out and without any delay mounted to the sample holder of the fluorescence spectrophotometer and the emission spectrum was recorded. Control experiments on slides with glues but without samples were carried out to treat as the same method and revealed that the effect of glue on fluorescence is negligible. The original emission spectra of the thin layer of the samples were collected before placing the glass slides into the bottles containing the arenes. For the cycle test, the slides were exposed to arene vapors, measured with fluorescence spectrophotometer, vacuumed at 25 °C for 4 h to remove the absorbed arenes, left in air under dark for half an hour, and then were utilized in the next around detection.
Synthetic procedures TCB-CMP. 1,5-Cyclooctadiene (194.71 mg, 1.80 mmol, dried over CaH2) was added to a solution of bis(1,5-cyclooctadiene)nickel(0) (495 mg, 1.80 mmol) and 2,2′-bipyridyl (280 mg, 1.80 mmol) in dehydrated DMF (10 mL), and the mixture was heated at 80 °C for 1 h. To the resulting purple solution was added TCB monomer (300 mg, 0.45 mmol), and the mixture was stirred at 80 °C for 72 h to produce deep purple suspensions. After cooling to room temperature, acetate acid (3 × 10 mL) was added to the mixture and stirred for 10 h. After filtration, the residue was washed with H2O (3 × 30 mL), CHCl3 (3 × 30 mL), and THF (3 × 30 mL), extracted by Soxhlet with H2O, CHCl3, methanol, acetone, and THF for 1 day, respectively, and dried at 150 °C under vacuum for 24 h to afford TCB-CMP, as yellow powder in 97% yield. Elemental analysis calcd. for (C30H24N3)n (theoretical formula for an infinite 2D polymer): C 84.48, H 5.67, N 9.85; found: C 79.81, H 5.51, N 9.12. IR (KBr, ν; cm–1): 2980, 2929, 1574, 1466, 1374, 1301, 1223, 1101, 993, 864, 793, 735, 685, 635, and 577. CB-LP. 1,5-Cyclooctadiene (160.48 mg, 1.47 mmol, dried over CaH2) was added to a solution of bis(1,5-cyclooctadiene)nickel(0) (405.7 mg, 1.47 mmol) and 2,2′-bipyridyl (230.2 mg, 1.47 mmol) in dehydrated DMF (10 mL), and the mixture was heated at 80 °C for 1 h. To the resulting purple solution was added 3,6-dibromo-9-methylcarbazole (200 mg, 0.59 mmol) at 80 °C, and the mixture was stirred at the temperature for 72 h to afford a deep purple suspension. After cooling to room temperature, acetate acid (3 × 10 mL) was added to the mixture and stirred S3
for 10h. After filtration, the residue was washed with H2O (3 × 20 mL), EtOH (3 × 20 mL), respectively, extracted by Soxhlet with H2O and EtOH for 1 day, respectively, and dried at 150 °C under vacuum for 24 h, to afford CB-LP as a yellow powder in 86% yield. Elemental analysis calcd. for (C14H11N)n, C 87.01, H 5.74,N 7.25; found: C 84.75, H 5.08, N 7.56. IR (KBr,
ν; cm–1): 3040, 2925, 2820, 1604, 1485, 1419, 1359, 1300, 1245, 1130, 1025, 875, 795, 653, and 569.
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Section 2 Infrared Spectra
Figure S1.
FT-IR spectra of TCB (black curve), TCB-CMP (red curve), CB (sky blue curve),
and CB-LP (blue curve).
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Section 3 NMR Spectra
Figure S2.
Solid-state
13
C CP/MAS NMR spectrum of TCB-CMP, recorded at a CP contact
time of 2 ms and a MAS rate of 15 kHz.
Signals with * symbols are side peaks.
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Section 4 XRD Pattern
Figure S3. XRD pattern of TCB-CMP.
S7
Section 5 Fluorescence Spectra
Figure S4.
Fluorescence spectral changes of TCB-CMP (A-D, I-L) and CB-LP (E-H, M-P)
upon exposure to the vapors of arenes.
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Section 6 Vapor Pressure and Redox Potential of Arenes Table S1. Vapor Pressure and Redox Potential of Arenes Compounds
Vapor pressure
Reduction Potential
LUMO
(mmHg)
(eV)
(eV)
NBS2
0.2416
-1.15
-3.65
DNTS3
1.44 × 10–4
-1.0
-3.8
NTS4
0.1602
-1.2
-3.6
BQS5
0.8
-0.5
-4.3
BenzeneS4
95.2
-3.42
-1.38
TolueneS5
28.4
-
-
ChlorobenzeneS6
11.8
-3.2
-1.6
MesityleneS7
2.57
-
-
-2.42
-2.38
TCB-CMP
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Section 7 Diagram of Fluorescence-on and -off Sensing of Arenes
Figure S5. Diagram of (A) fluorescence-off and (B) fluorescence-on Sensing of Arenes.
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Section 8 Supporting References 1.
Ji, L.; Fang, Q.; Yuan, M. S.; Liu, Z. Q.; Shen, Y. X.; Chen, H. F. Org. Lett. 2010, 12, 5192-9195.
2.
Yang J.-S.; Swager, T. M. J. Am. Chem. Soc. 1998, 120, 11864.
3.
Lan, A.; Li, K.; Wu, H.; Olson, D. H.; Emge, T. J.; Ki, W.; Hong, M.; Li, J. Angew.Chem., Int. Ed. 2009, 48, 2334.
4.
a) Mortensen, J.; Heinze, J. Angew.Chem. Int. Ed. 1984, 23, 84. b) http://www.epa.gov/ttn/atw/hlthef/benzene.html
5.
http://www.epa.gov/ttn/atw/hlthef/toluene.html
6.
a) Afanas’ev, V.A.; Makarov, A.F.; Khidekel’, M.L. Russian Chemical Bulletin,1982, 31, 845. b) http://www.jtbaker.com/msds/englishhtml/C2475.htm (vsAg/AgCl electrode).
7.
Kassel, L. S. J. Am. Chem. Soc. 1936, 58, 670-671.
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