S1
Supporting Information for
Solvent Dependent Intramolecular Excimer Emission of Di(1-pyrenyl)silane and Di(1-pyrenyl)methane Derivatives
Shin-ichi Kondo*†‡, Yuka Taguchi†, and Yi Bie†
†Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, Yamagata
990-8560, Japan ‡Institute for Regional Innovation, Yamagata University, Kanakame, Kaminoyama, Yamagata 999-3101,
Japan
E-mail: [email protected]
Contents
General ···················································································································· S2
Synthesis of di(1-pyrenyl)di(trimethylsiloxy)silane ······························································ S2
Synthesis of dimethyldi(1-pyrenyl)silane ·········································································· S4
Synthesis of dimethylphenyl(1-pyrenyl)silane ···································································· S5
Synthesis of di(1-pyrenyl)methanol ················································································· S7
Synthesis of di(1-pyrenyl)methanone ··············································································· S8
Synthesis of di(1-pyrenyl)methane ·················································································S10
Synthesis of phenyl(1-pyrenyl)methanol ·········································································· S11
Measurements of UV-vis spectra of probes ·······································································S13
Measurements of fluorescence spectra of probes ································································S13
Determination of quantum yields ··················································································S13
Fig. S15. UV-vis spectra of 1–4 in organic solvents ·······························································S14
Fig. S16. Fluorescence spectra of 1c in organic solvents ··························································S15
Fig. S17. Fluorescence spectra of 1b–4 in organic solvents ······················································S16
Fig. S18. Effect of concentration of 1c on the ratio of fluorescence intensities ································S17
Fig. S19. Effect of solvent parameters on the ratios of excimer-like and monomer emissions (I470/I378) of
1a–c ·······················································································································S18
Fig. S20. Effect of solvent parameters on the ratios of excimer-like and monomer emissions (I447/I377) of 3a
and 3b ·····················································································································S19
Fig. S21. Excitation spectra of 1c in CHCl3, DMSO, and MeCN ················································S20
Fig. S22. Effect of DMSO–CHCl3 on fluorescence spectra of 1c ················································S21
Fig. S23. Effect of water–DMSO on fluorescence spectra of 1c ·················································S21
Fig. S24. UV-vis and fluorescence spectra of dimethyldi(1-naphthyl)silane ···································S21
Fig. S25. Fluorescence spectra of 3a under aerobic and argon saturated conditions in DMSO··············S22
Table S1 The ratios of the fluorescence intensities 1a-c, 3a, and 3b in various solvents ·····················S22
Electronic Supplementary Material (ESI) for RSC Advances.This journal is © The Royal Society of Chemistry 2014
S2
General
All reagents used were of analytical grade. Tetrahydrofuran was dried over Na/benzophenone. NMR
spectra were measured on a JEOL ECA-500 (500 MHz) spectrometer. UV-vis spectra were recorded
on JASCO V-560 and Shimadzu UV-2500PC spectrometers with a thermal regulator (±0.5 ºC).
Fluorescence spectra were recorded on Hitachi F-7000 and Jobin Yvon Horiba Fluoromax-3
spectrofluorometers under aerobic condition. HRMS were measured in CHCl3 : MeOH = 3: 1 at 150–
200 ºC on a ABI Sciex TripleTOF 4600. Column chromatography was performed by using Silica Gel
60N from Kanto Reagents. Melting points were determined with a Yanagimoto MP-J3 micro melting
point apparatus and are uncorrected. Di(1-pyrenyl)silanediol was prepared according to the previously
reported method.1
Synthesis of di(1-pyrenyl)bis(trimethylsiloxy)silane (1b)
Into a solution of di(1-pyrenyl)silanediol (0.10 g, 0.22 mmol) in THF, pyridine (0.50 ml, 6.2 mmol) and
chlorotrimethylsilane (0.11 ml, 0.86 mmol) were added and the mixture was stirred for 3 h under argon
atmosphere at r.t. The mixture was extracted with chloroform/dil. HCl and the organic layer was dried over
anhydrous sodium sulfate. After evaporation under reduced pressure, the residue was chromatographed on
silica gel column chromatography (CHCl3 : hexane = 1 : 1, v/v as an eluent) to give the product as colorless
needles. Yield 0.11 g, 83%. M. p. 221.2–222.2 ºC. 1H NMR (500 MHz, CDCl3) δ 8.48 (d, 2H, J = 9.0 Hz),
8.46 (d, 2H, J = 7.5 Hz), 8.19 (d, 2H, J = 7.5 Hz), 8.16 (d, 2H, J = 7.5 Hz), 8.10 (d, 2H, J = 8.8 Hz), 8.09 (d,
2H, J = 7.5 Hz), 8.08 (d, 2H, J = 8.8 Hz), 7.95 (t, 2H, J = 7.5 Hz), 7.89 (d, 2H, J = 9.0 Hz), 0.08 (s, 18H). 13C NMR (126 MHz, CDCl3) δ 135.78, 133.12, 132.78, 132.69, 131.21, 130.69, 128.46, 128.16, 127.55,
127.01, 125.70, 125.18, 125.04, 124.75, 124.58, 124.25, 1.84. 29Si NMR (99 MHz, CDCl3) δ 10.8, −21.8.
HRMS (ESI, positive mode): Calcd for C38H36NaO2Si3 [M+Na]+, 631.1915. Found 631.1872.
S3
Fig. S1. 500 MHz 1H NMR spectrum of di(1-pyrenyl)di(trimethylsiloxy)silane in CDCl3.
Fig. S2. 126 MHz 13C NMR spectrum of di(1-pyrenyl)di(trimethylsiloxy)silane in CDCl3.
010
.020
.030
.040
.050
.0
9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
485
8.
471
8.
466
8.
456
8.
198
8.
184
8.
092
8.
086
7.
966
7.
951
7.
898
7.
881
7.
252
1.
525
0.
089
0.
082
0.
076
0.
000
17.4
0
6.05
4.00
3.96
2.03
2.00
00.
10.
20.
3
210.0 200.0 190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
135
.775
133
.124
132
.780
132
.685
131
.206
130
.691
128
.459
128
.164
127
.553
127
.009
125
.703
125
.178
125
.035
124
.749
124
.577
124
.253
77.
248
77.
000
76.
742
1.
838
-0.
012
S4
Synthesis of dimethyldi(1-pyrenyl)silane (1c)
Into a solution of 1-bromopyrene (1.00 g, 3.56 mmol) in THF (10 mL), was added n-BuLi/hexane (1.64 M,
2.60 mL, 4.27 mmol) at −78 ºC under argon atmosphaere. The mixture was stirred at −78 ºC for 1 h. Then
tetrachlorosilane (0.204 mL, 1.78 mmol) was slowly added into the solution and the mixture was stirred at
−78 ºC for 30 min, then stirred at −40 ºC for additional 30 min. After the mixture was cooled again to −78
ºC, freshly prepared MeMgI from iodomethane (ca. 2.6 M, 5.5 ml, 8 equiv) was added in the solution. The
mixture was allowed to warm to room temperature and stirred overnight. Aqueous ammonium chloride
(sat.) was added to the mixture, and the mixture was extracted with ether (50 mL 2). The combined
organic layer was washed with brine and dried over anhydrous sodium sulfate. After evaporation under
reduced pressure, the residue was purified by column chromatography on silica gel with hexane as an
eluent to give the product (191 mg, 23%) as colorless solid: M. p. 251.2–252.0 ºC. 1H NMR (500 MHz,
CDCl3) δ 8.41 (d, 2H, J = 7.5 Hz), 8.22 (d, 2H, J = 9.2 Hz), 8.21 (d, 2H, J = 9.2 Hz), 8.15 (d, 2H, J = 7.5
Hz), 8.09 (s, 4H), 8.06 (d, 2H, J = 7.5 Hz), 7.93 (t, 2H, J = 7.5 Hz), 7.81 (d, 2H, J = 9.2 Hz), 1.09 (s, 6H). 13C NMR (126 MHz, CDCl3) δ 135.84, 134.43, 132.77, 132.42, 131.24, 130.58, 128.06, 127.75, 127.51,
127.18, 125.78, 125.21, 125.09, 124.80, 124.75, 124.42, 0.60. HRMS (ESI, positive mode): Calcd for
C34H24NaSi [M+Na]+, 483.1539. Found 483.1503.
Fig. S3. 500 MHz 1H NMR spectrum of dimethyldi(1-pyrenyl)silane in CDCl3.
01.
02.
03.
04.
05.
06.
07.
0
9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
414
8.
399
8.
229
8.
221
8.
208
8.
155
8.
140
8.
088
8.
047
7.
934
7.
823
7.
804
7.
252
1.
541
1.
085
-0.
000
6.18
4.09
3.97
2.07
2.03
2.03
2.00
1.87
S5
Fig. S4. 126 MHz 13C NMR spectrum of dimethyldi(1-pyrenyl)silane in CDCl3.
Synthesis of dimethylphenyl(1-pyrenyl)silane (2)
Into a solution of 1-bromopyrene (0.75 g, 2.67 mmol) in THF (10 mL), was added n-BuLi/hexane (1.64 M,
1.95 mL, 3.20 mmol) at −78 ºC under argon atmosphere. The mixture was stirred at −78 ºC for 1 h. Then
phenyltrichlorosilane (0.428 mL, 2.67 mmol) was slowly added into the solution and the mixture was
stirred at −78 ºC for 30 min, then stirred at −40 ºC for additional 30 min. After the mixture was cooled
again to −78 ºC, freshly prepared MeMgI from iodomethane (ca. 2.6 M, 8.4 mL, 8 equiv) was added in the
solution. The mixture was allowed to warm to room temperature and stirred overnight. Aqueous
ammonium chloride (sat.) was added to the mixture, and the mixture was extracted with ether (45 mL 2).
The combined organic layer was washed with brine and dried over anhydrous sodium sulfate. After
evaporation under reduced pressure, the residue was purified by column chromatography on silica gel with
hexane as an eluent to give the product (364 mg, 41%) as pale yellow solid: M. p. 167.5–168.0 ºC. 1H
NMR (500 MHz, CDCl3) δ 8.23 (d, 1H, J = 7.5 Hz), 8.19 (d, 1H, J = 9.2 Hz), 8.17 (d, 2H, J = 7.5 Hz), 8.14
(d, 1H, J = 7.5 Hz), 8.09 (d, 1H, J = 9.2 Hz), 8.06 (d, 1H, J = 9.2 Hz), 7.98 (t, 1H, J = 7.5 Hz), 7.96 (d, 1H,
J = 9.2 Hz), 7.58 (dd, 2H, J1 = 7.7, J2 = 1.7 Hz), 7.36 (tt, 1H, J1 = 7.4 Hz, J2 = 1.7 Hz), 7.34–7.31 (m, 2H),
0.83 (s, 6H). 13C NMR (126 MHz, CDCl3) δ 139.12, 135.90, 134.23, 133.13, 132.97, 132.44, 131.25,
130.59, 129.08, 128.06, 128.04, 127.94, 127.50, 127.05, 125.81, 125.24, 125.11, 124.80, 124.65, 124.09,
−0.57. HRMS (ESI, positive mode): Calcd for C24H20NaSi [M+Na]+, 359.1226. Found 359.1195.
-0.0
4-0
.02
00.
020.
040.
060.
080.
10.
120.
140.
160.
180.
2
190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
135
.842
134
.430
132
.771
132
.418
131
.244
130
.577
128
.059
127
.753
127
.505
127
.181
125
.779
125
.207
125
.092
124
.797
124
.749
124
.415
77.
258
77.
000
76.
752
0.
598
-0.
012
S6
Fig. S5. 500 MHz 1H NMR spectrum of dimethylphenyl(1-pyrenyl)silane in CDCl3.
Fig. S6. 126 MHz 13C NMR spectrum of dimethylphenyl(1-pyrenyl)silane in CDCl3.
01.
02.
03.
04.
05.
06.
07.
08.
09.
010
.011
.012
.013
.014
.015
.016
.017
.018
.019
.020
.021
.022
.0
9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
221
8.
195
8.
179
8.
177
8.
164
8.
083
8.
074
7.
981
7.
973
7.
585
7.
581
7.
569
7.
566
7.
369
7.
356
7.
344
7.
329
7.
247
1.
545
0.
834
0.
827
0.
821
0.
000
6.00
3.86
2.82
1.93
1.86
1.85
0.97
00.
10.
20.
30.
40.
5
190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
139
.123
135
.899
134
.230
133
.133
132
.971
132
.437
131
.254
130
.586
129
.079
128
.040
127
.944
127
.496
127
.048
125
.808
125
.235
125
.111
124
.091
77.
258
77.
000
76.
752
-0.
566
SiMe
Me
SiMe
Me
S7
Synthesis of di(1-pyrenyl)methanol (3a)
Into a solution of 1-bromopyrene (0.50 g, 1.78 mmol) in THF (5 mL), was added n-BuLi/hexane (1.64 M,
1.30 mL, 2.13 mmol) at −78 ºC under argon atmosphere. The mixture was stirred at −78 ºC for 1 h. Then
1-pyrenecarboxyaldehyde (0.41 g, 1.78 mmol) in 5 mL of THF was slowly added into the solution and the
mixture was stirred at −78 ºC for 30 min. The mixture was allowed to warm at room temperature and
stirred overnight. Water (10 mL) was added to the mixture, and ether (10 mL) was also added to the
mixture. The produced solid was filtered and the solid was washed with ether to give the product (0.33 g,
43%) as pale yellow solid: M. p. 248.5–249.5 ºC (decomp, lit.2 254 ºC). 1H NMR (500 MHz, DMSO-d6) δ
8.49 (dd, 2H, J1 = 9.2, J2 = 2.3 Hz), 8.29 (d,2H, J = 7.5 Hz), 8.25 (d, 2H, J = 6.9 Hz), 8.24 (d, 2H, J = 7.5
Hz), 8.15 (m, 6H), 8.06 (t, 2H, J = 7.5 Hz), 8.04 (d, 2H, J = 6.9 Hz), 7.82 (d, 1H, J = 4.0 Hz), 6.55 (d, 1H, J
= 4.0 Hz). 13C NMR (126 MHz, DMSO-d6 ) δ 138.41, 130.83, 130.18, 130.10, 127.72, 127.56, 127.42,
127.15, 126.25, 125.38, 125.35, 125.16, 124.74, 124.11, 124.00, 123.42, 68.33. HRMS (ESI, positive
mode): Calcd for C33H20NaO [M+Na]+, 455.1406. Found 455.1376.
01.
02.
03.
04.
05.
06.
07.
08.
0
10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
499
8.
480
8.
301
8.
285
8.
241
8.
225
8.
161
8.
158
8.
146
8.
143
8.
072
8.
057
8.
051
8.
035
6.
553
6.
543
6.05
4.06
4.00
2.11
2.08
1.00
1.00
Fig. S7. 500 MHz 1H NMR spectrum of di(1-pyrenyl)methanol in DMSO-d6.
S8
Fig. S8. 126 MHz 13C NMR spectrum of di(1-pyrenyl)methanol in DMSO-d6.
Synthesis of di(1-pyrenyl)methanone
Into a suspension of pyridinium chlorochromate (0.199 g, 0.925 mmol) and Hyflo Super-Cel (0.199 g) in
dichloromethane (100 mL), was slowly added di(1-pyrenyl)methanol (0.20 g, 0.462 mmol) at r.t. under
argon atmosphere. The mixture was stirred at r.t. for 2 h and column chromatographed on silica gel
(CH2Cl2) to give the product (0.195 g, 98%) as yellow solid. M. p. 260.0–262.0 ºC (lit.3 234–235 ºC). 1H NMR (500 MHz, CDCl3) δ 8.82 (d, 2H, J = 9.5Hz), 8.28 (d, 2H, J = 8.0Hz), 8.26 (d, 2H, J = 8.0Hz),
8.21 (d, 2H, J = 8.6Hz), 8.17 (d, 2H, J = 9.8Hz), 8.12–8.08(m, 6H), 8.08 (t, 2H, J = 8.0Hz) ; 13C NMR (126
MHz, CDCl3) δ 200.72, 134.39, 133.91, 131.27, 130.77, 130.51, 129.71, 129.59, 129.14, 127.35, 126.56,
126.43, 126.27, 125.07, 124.54, 124.01.
-0.0
2-0
.01
00.
010.
020.
030.
040.
050.
060.
070.
080.
090.
10.
110.
120.
130.
140.
15
200.0190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
138
.412
130
.829
130
.181
130
.095
128
.311
127
.720
127
.558
127
.424
127
.148
126
.251
125
.354
125
.164
124
.744
124
.114
124
.000
123
.418
68.
334
S9
01.
02.
03.
04.
05.
06.
0
9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
825
8.
806
8.
276
8.
272
8.
256
8.
220
8.
203
8.
180
8.
161
8.
114
8.
110
8.
096
8.
080
7.
254
0.
000
8.37
4.07
4.05
2.00
Fig. S9. 500 MHz 1H NMR spectrum of di(1-pyrenyl)methanone in CDCl3.
Fig. S10. 126 MHz 13C NMR spectrum of di(1-pyrenyl)methanone in CDCl3.
00.
10.
20.
30.
4
210.0200.0 190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
200
.721
134
.391
133
.905
131
.272
130
.767
130
.509
129
.708
129
.594
129
.136
127
.352
126
.560
126
.427
126
.265
125
.072
124
.538
124
.014
S10
Synthesis of di(1-pyrenyl)methane (3b)
A suspension of di(1-pyrenyl)methanone (0.10 g, 0.232 mmol), hydrazine monohydrate (0.031 g, 0.627
mmol), and potassium hydroxide (0.102 g, excess) in triethylene glycol (2 mL) was stirred at 180 ºC
overnight under argon atmosphere. The mixture was filtered with suction and the filtrate was extracted with
chloroform (10 mL2) and water. The combined organic layer was twice washed with water and dried over
anhydrous sodium sulfate. After filtration, the solution was evaporated under reduced pressure. The residue
was purified by column chromatography on silica gel with CHCl3:hexane = 1:1 (v/v) as an eluent to give
the product (19 mg, 20%) as pale yellow solid: M. p. 226.4–228.0 ºC (decomp. lit.2 235 ºC). 1H NMR (500 MHz, CDCl3) δ 8.36 (d, 2H, J = 9.8Hz), 8.20 (d, 2H, J = 7.4Hz), 8.18 (d, 2H, J = 7.4Hz),
8.10 (d, 2H, J = 7.4Hz), 8.06 (d, 2H, J = 8.6Hz), 8.05–8.02(m, 6H), 8.01 (t, 2H, J = 7.4Hz), 7.66 (d, 2H, J
= 8.0Hz), 5.47 (s, 2H). 13C NMR (126 MHz, CDCl3) δ 134.44, 131.45, 130.92, 130.16, 129.16, 127.81,
127.72, 127.54, 126.91, 125.93, 125.14, 125.08, 125.00, 124.97, 124.93, 123.42, 36.47.
01.
02.
03.
04.
05.
06.
07.
08.
09.
010
.011
.012
.013
.014
.015
.0
9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
374
8.
354
8.
206
8.
193
8.
178
8.
104
8.
085
8.
068
8.
051
8.
043
8.
036
8.
029
8.
025
8.
014
7.
999
7.
660
7.
644
7.
255
5.
466
-0.
000
7.87
4.02
2.03
2.00
2.00
1.75
Fig. S11. 500 MHz 1H NMR spectrum of di(1-pyrenyl)methane in CDCl3.
S11
00.
10.
20.
3
190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
134
.440
131
.445
130
.920
130
.157
129
.156
127
.811
127
.715
127
.544
126
.905
125
.932
125
.140
125
.083
124
.997
124
.968
124
.930
123
.423
36.
472
Fig. S12. 126 MHz 13C NMR spectrum of di(1-pyrenyl)methane in CDCl3.
Synthesis of phenyl(1-pyrenyl)methanol (4)4
Into a solution of 1-bromopyrene (1.00 g, 3.56 mmol) in THF (7 mL), was added n-BuLi/hexane (1.64 M,
2.60 mL, 4.27 mmol) at −78 ºC under argon atmosphere. The mixture was stirred at −78 ºC for 1 h. Then
freshly distilled benzaldehyde (0.453 g, 4.27 mmol) in 5 mL of THF was slowly added into the solution and
the mixture was stirred at −78 ºC for 10 min. The mixture was allowed to warm at room temperature and
stirred overnight. Water was added to the mixture, and the mixture was extracted with CHCl3 (10 mL2).
After evaporation under reduced pressure, the residue was chromatographed on silica gel (CHCl3 as an
eluent) to give the product (505 mg, 46.0%) as pale yellow solid: M. p. 126.2–127.2 ºC (lit.2 126 ºC) 1H NMR (500 MHz, CDCl3) δ 8.31 (d, 1H, J = 10.0Hz), 8.18–8.17 (m, 3H), 8.15 (d, 1H, J = 7.5Hz), 8.05–
8.04 (m, 3H), 7.99 (t, 1H, J = 7.5Hz), 7.44 (d, 2H, J = 7.5Hz), 7.32 (t, 2H, J = 7.5Hz), 7.27 (t, 1H, J =
7.5Hz), 6.87 (d, 1H, J = 3.3Hz) , 2.54 (d, 1H, J = 3.5Hz). 13C NMR (126 MHz, CDCl3) δ 143.60, 136.57, 131.30, 131.00, 130.59, 128.55, 128.07, 127.78, 127.60,
127.46, 127.43, 126.96, 125.97, 125.34, 125.17, 125.01, 124.88, 124.78, 124.68, 123.04, 73.57.
S12
01.
02.
03.
04.
05.
06.
07.
08.
09.
010
.0
9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0
8.
318
8.
298
8.
187
8.
171
8.
169
8.
145
8.
054
8.
036
8.
005
7.
990
7.
452
7.
437
7.
325
7.
251
6.
874
6.
868
2.
543
2.
537
-0.
000
4.03
3.05
2.00
2.01
1.71
1.01
1.00
1.00
1.00
Fig. S13. 500 MHz 1H NMR spectrum of phenyl(1-pyrenyl)methanol in CDCl3.
00.
10.
20.
30.
4
190.0 180.0 170.0 160.0 150.0 140.0 130.0 120.0 110.0 100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
143
.597
136
.567
131
.302
130
.996
130
.586
128
.545
127
.782
127
.601
127
.458
127
.429
126
.962
125
.970
125
.340
125
.169
125
.006
124
.882
124
.777
124
.682
123
.041
73.
566
Fig. S14. 126 MHz 13C NMR spectrum of phenyl(1-pyrenyl)methanol in CDCl3.
S13
Measurements of UV-vis spectra of probes
Into a solvent (3 mL) in a quarts cell, an aliquots (5.0 μL) of the stock solution of probes (2.510−3 mol
dm−3 for 1a–c, 2, 3b, and 4 in chloroform, 2.510−3 mol dm−3 for 3a in DMSO, and 2.510−4 mol dm−3 for
1c in chloroform for measurements in ethylene glycol) was added with a microsyringe and a UV-vis
spectrum of the solution was measured at 298 0.5 K. The process was repeated for additional two times
(the concentrations of the all probes were up to 1.2510−5 mol dm−3 except for 1c in ethylene glycol,
2.010−6 mol dm−3). The molar absorption coefficients at each wavelength were calculated from the slope
of the absorbance against the concentration of the probes by linear regressions. The solubility of 1b in
ethylene glycol is too low to determine the molar absorption coefficients. The results are shown in Fig. S15.
Measurements of fluorescence spectra of probes
Into a solvent (3 mL) in a quarts cell, an aliquots (8.0 μL) of the stock solution of probes (2.510−4 mol
dm−3 for 1a–c, 2, 3b, and 4 in chloroform and 2.510−4 mol dm−3 for 3a in DMSO) was added with a
microsyringe and a fluorescence spectrum of the solution excited at 348 nm was measured at 298 0.5 K.
The process was repeated for additional two times. The concentrations of the all probes were up to 2.010−6
mol dm−3. The fluorescence intensities at each wavelength were calculated from the slope of the intensity
against the concentration of the probes by linear regressions. The results are summarized in Figs. 1 and
S17.
Determination of quantum yields
Fluorescence quantum yields were determined from the derived fluorescence spectrum of each species
using quinine sulfate as standard (QS = 0.546 in 0.5 mol dm-3 H2SO4 at 298 K) and were corrected for
solvent refractive index. Into an appropriate solvent (3 mL) in a quarts cell, an aliquots of the stock solution
of probes was added with a microsyringe and UV-vis and fluorescence spectra (excited at 348 nm) were
measured at 298 0.5 K. The process was repeated for additional at least four times. The integrated
fluorescence intensities of the probes were plotted against the UV-vis absorbance at each concentrations to
give the slope F/A, in which F and A are the integrated fluorescence intensity and the absorbance of the
probes, respectively. The same procedure was performed for quinine sulfate in 0.5 mol dm-3 H2SO4 at 298
0.5 K to give FQS/AQS, in which FQS and AQS are the integrated fluorescence intensity and the absorbance of
the quinine sulfate, respectively. The quantum yield of the probeswas calculated according to the
equation;
//
where n and nQS are the refractive index of the measured solvent and 0.5 mol dm-3 H2SO4, respectively.
S14
a 1.2
1.0
0.8
0.6
0.4
0.2
0.0
/
10
5M
-1 c
m-1
400360320280Wavelength / nm
b 1.2
1.0
0.8
0.6
0.4
0.2
0.0
/
10
5M
-1 c
m-1
400360320280Wavelength / nm
c 1.2
1.0
0.8
0.6
0.4
0.2
0.0
/
10
5M
-1 c
m-1
400360320280Wavelength / nm
d
e 1.2
1.0
0.8
0.6
0.4
0.2
0.0
/
10
5M
-1 c
m-1
400360320280Wavelength / nm
f 1.2
1.0
0.8
0.6
0.4
0.2
0.0
/
10
5M
-1 c
m-1
400360320280Wavelength / nm
g 1.2
1.0
0.8
0.6
0.4
0.2
0.0
/
10
5M
-1 c
m-1
400360320280Wavelength / nm
Fig. S15. UV-vis spectra of 1a (a), 1b (b), 1c (c), 2 (d), 3a (e), 3b (f), and 4 (g) in DMSO (―), ethylene
glycol (―), DMF (―), MeCN (―), CHCl3 (―), and cyclohexane (―). A UV-vis spectrum of 1b in
ethylene glycol is not shown due to the low solubility of 1b.
1.2
1.0
0.8
0.6
0.4
0.2
0.0
/ 1
05M
-1 c
m-1
400360320280Wavelength / nm
S15
a 100
80
60
40
20
0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
b 100
80
60
40
20
0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
c 100
80
60
40
20
0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
Fig. S16. Fluorescence spectra of 1c (a) in DMSO (―), ethylene glycol (―), DMF (―), MeCN (―),
CHCl3 (―), and cyclohexane (―); (b) in EtOH (―), 2-PrOH (―), 1-BuOH (―), MeOH (―), Et2O (―),
and THF (―); and (c) in acetone (―), ethyl acetate (―), toluene (―) , and hexane (―). ex = 348 nm at
298 K.
S16
a b
c 1.0
0.8
0.6
0.4
0.2
0.0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
d 1.0
0.8
0.6
0.4
0.2
0.0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
e 1.0
0.8
0.6
0.4
0.2
0.0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
Fig. S17. Normalized fluorescence spectra of 1b (a), 1c (b), 2 (c), 3b (d), and 4 (e) in DMSO (―), ethylene
glycol (―), DMF (―), MeCN (―), CHCl3 (―), and cyclohexane (―). A fluorescence spectrum of 1b in
ethylene glycol is not shown due to the low solubility of 1b. ex = 348 nm at 298 K.
1.0
0.8
0.6
0.4
0.2
0.0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
1.0
0.8
0.6
0.4
0.2
0.0Flu
ore
sce
nce
inte
nsi
ty /
Arb
650600550500450400
em / nm
S17
0.25
0.20
0.15
0.10
0.05
0.00
F4
70/F
37
93020100
[1c] / 10-6
mol dm-3
Fig. S18. Effect of concentration of 1c on the ratio of fluorescence intensities at 470 and 379 nm in DMSO
(), MeCN (), and CHCl3 (). ex = 348 nm at 298 K.
S18
a 0.6
0.5
0.4
0.3
0.2
0.1
0.0
I 47
0 /
I3
78
50403020100
r
b
c 0.6
0.5
0.4
0.3
0.2
0.1
0.0
I 47
0 /
I3
78
403020100AN
d 0.6
0.5
0.4
0.3
0.2
0.1
0.0
I 47
0 /
I3
78
0.60.40.20.0
DNN
e 0.6
0.5
0.4
0.3
0.2
0.1
0.0
I 47
0 /
I3
78
0.60.40.2
ETN
f
0.5
0.4
0.3
0.2
0.1
I 47
0 /
I3
78
0.300.200.10f
Fig. S19. Effect of solvent parameters, namely dielectric constant (εr), viscosity, acceptor number (AN),
donor number (DNN), normalized ET value (ETN), and solvent orientation polarizability factor (Δf) on the
ratios of excimer-like and monomer emissions (I470/I378) of 1a–c. ex = 348 nm. : 1a, : 1b, and : 1c.
0.6
0.5
0.4
0.3
0.2
0.1
0.0
I 47
0 /
I3
78
2015105Viscosity / cP
S19
a b
c d
e f
Fig. S20. Effect of the ratios of excimer-like and monomer emissions (I447/I377) of 3a and 3b on solvent
parameters, namely dielectric constant (εr), viscosity, acceptor number (AN), donor number (DNN),
normalized ET value (ETN), and solvent orientation polarizability factor (Δf) . ex = 348 nm. : 3a and :
3b.
1.0
0.8
0.6
0.4
0.2
0.0
I 447
/ I 3
77
50403020100
εr
1.0
0.8
0.6
0.4
0.2
0.0
I 447
/ I 3
77
2015105Viscosity / cP
1.0
0.8
0.6
0.4
0.2
0.0
I 447
/ I 3
77
403020100AN
1.0
0.8
0.6
0.4
0.2
0.0
I 447
/ I 3
77
0.60.40.20.0
DNN
1.0
0.8
0.6
0.4
0.2
0.0
I 447
/ I 3
77
0.60.40.2
ETN
1.0
0.8
0.6
0.4
0.2
0.0
I 447
/ I 3
77
0.300.200.10Δf
S20
Fig. S21. (Left) Excitation spectra of 1c in CHCl3 at 379 (―) and 470 nm (―), in DMSO at 379 (―) and
470 nm (―), and in MeCN at 379 (―) and 470 nm (―), respectively. (Right) UV-vis spectra of 1c in the
corresponding solvents were overlapped as dotted lines to the normalized fluorescence spectra,
respectively.
1.0
0.8
0.6
0.4
0.2Abs
an
d N
orm
aliz
ed
F
360340320300280260
Wavelength / nm
2500
2000
1500
1000
500
0Flu
ore
sce
nce
inte
nsi
ty /
Arb
360340320300280260
ex / nm
800
600
400
200
Flu
ore
scen
ce in
tens
ity /
Arb
360340320300280260
ex / nm
1.0
0.8
0.6
0.4
0.2
0.0
Ab
s a
nd
No
rma
lized
F
360340320300280260
Wavelength / nm
1400
1200
1000
800
600
400
200
0Flu
ore
sce
nce
inte
nsi
ty /
Arb
360340320300280260
ex / nm
1.0
0.8
0.6
0.4
0.2Abs
and
No
rmal
ized
F
360340320300280260
Wavelength / nm
S21
0.25
0.20
0.15
0.10
0.05
0.00
F4
70/F
37
9
100806040200
DMSO% (v/v) in CHCl3
1.0
0.8
0.6
0.4
0.2
0.0
No
rma
lize
d f
luo
resc
en
ce in
ten
sity
650600550500450400
em / nm
DMSO%
Fig. S22. Effect of DMSO–CHCl3 on fluorescence spectra of 1c. [1c] = 2.010−6 mol dm−3, ex = 348 nm at
298 K.
1.0
0.8
0.6
0.4
0.2
0.0
No
rma
lize
d fl
uo
resc
en
ce in
ten
sity
650600550500450400
em / nm
0.4
0.3
0.2
0.1
0.0
F4
70/F
379
50403020100
H2O% (v/v) in DMSO
403020100%
Fig. S23. Effect of water–DMSO on fluorescence spectra of 1c. [1c] = 2.010−6 mol dm−3, ex = 348 nm at
298 K.
a b
Fig. S24. UV-vis (a) and fluorescence (b) spectra of dimethyldi(1-naphthyl)silane in DMSO (―), MeCN
(―), and CHCl3 (―).
1.5
1.0
0.5
0.0
/
10
4 M
-1cm
-1
400360320280Wavelength / nm
1.0
0.8
0.6
0.4
0.2
0.0
No
rma
lize
d F
440400360320
em / nm
S22
Fig. S25. Fluorescence spectra of 3a under aerobic (—) and argon saturated (—) conditions in DMSO. [3a]
= 2.010−6 mol dm−3, ex = 348 nm.
Table S1 The ratios of the fluorescence intensities of excimer and monomer emissions of 1a-c, 3a, and 3b
in various solvents
I470/I378 I447/I377
solvents 1a 1b 1c 3a 3b
hexane 0.0074 0.0102 NDa
cyclohexane 0.0125 0.0234 0.0095 NDa 0.0233
benzene 0.0084
toluene 0.0082 0.0094 0.0530
ether 0.0132 0.0090 0.0522
chloroform 0.0192 0.0309 0.0098 0.0653 0.0278
ethyl acetate 0.0136 0.0081 0.0565
THF 0.0128 0.0083 0.0602
1-butanol 0.0482 0.0096 0.0664
2-propanol 0.0818 0.0084 0.0674
acetone 0.0389 0.0160 0.1343
ethanol 0.0106 0.0786
methanol 0.0253 0.0165 0.1185
acetonitrile 0.1439 0.0840 0.0558 0.3830 0.0491
DMF 0.1944 0.0872 0.0691 0.4117 0.0589
1,2-ethanediol 0.2056 NDa 0.0987 0.5336 0.0643
DMSO 0.5765 0.2592 0.2300 0.9618 0.1564 a Not determined due to the solubility of the compound in these solvents.
2.0
1.5
1.0
0.5
F /
Arb
650600550500450400
em / nm
S23
References
1. S. Kondo, Y. Bie and M. Yamamura, Org. Lett., 2013, 15, 520-523.
2. H. Reimlinger, J.-P. Golstein, J. Jadot and P. Jung, Chem. Ber., 1964, 349-362.
3. A. Berg, Acta Chem. Scand., 1949, 3, 655-659.
4. K. K. Laali and P. E. Hansen, J. Org. Chem., 1997, 62, 5804-5810.
