Survey, fluorescence spectra, and solubility of liquid cyanine dyes

Article abstract of DOI:10.1039/C6NJ02160C

We synthesized four liquid cyanine dyes, namely N,N′-didodecyl 44,N,N′-dioctadecyl indolenium 45,N,N′-bis(2,5,8-trioxa-10-octadecanyl)benzoxazolium 50 and benzothiazolium 51, which have a bis(perfluorobutylsulfonyl)imide anion. In the neat form, these liquid dyes exhibit more intense fluorescence at ?196 °C than at 25 °C. The liquid N,N′-dialkylated indolenium derivatives 44 and 45 exhibited larger solubility in hexane than the corresponding solid derivatives. In addition, the liquid N,N′-bis(2,5,8-trioxa-10-octadecanyl)benzoxazolium and benzothiazolium derivatives 50 and 51 were more soluble in propanol than the corresponding solid derivatives.

Full text of DOI:10.1039/C6NJ02160C

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Survey, fluorescence spectra, and solubility
of liquid cyanine dyes†
Cite this:DOI: 10.1039/c6nj02160c
Masaki Matsui,* Takaya Yamamoto, Yasuhiro Kubota and Kazumasa Funabiki
We synthesized four liquid cyanine dyes, namely N,N0-didodecyl 44, N,N0-dioctadecyl indolenium 45, N,N0-
bis(2,5,8-trioxa-10-octadecanyl)benzoxazolium 50 and benzothiazolium 51, which have a bis(perfluorobutyl-
sulfonyl)imide anion. In the neat form, these liquid dyes exhibit more intense fluorescence at ꢀ196 1C than at
25 1C. The liquid N,N0-dialkylated indolenium derivatives 44 and 45 exhibited larger solubility in hexane than the
corresponding solid derivatives. In addition, the liquid N,N0-bis(2,5,8-trioxa-10-octadecanyl)benzoxazolium and
benzothiazolium derivatives 50 and 51 were more soluble in propanol than the corresponding solid derivatives.
Received (in Montpellier, France)
12th July 2016,
Accepted 11th October 2016
DOI: 10.1039/c6nj02160c
www.rsc.org/njc
N-alkylated with alkyl iodides 6–9 and/or N-oxaalkylated with
an oxaalkyl tosylate 10 to yield N-alkyl 11–18 and/or N-oxaalkyl
Introduction
Cyanine dyes are very interesting and important compounds derivatives 19–22, which were allowed to react with triethoxy-
owing to their excellent photophysical properties such as their methane to yield cyanine iodides 23–30 and/or tosylates 31–34,
high absorption coefficient, high fluorescence quantum yield, respectively. These compounds were treated with tetrafluoroboric
and long absorption and emission wavelengths. Therefore, they acid (35) and sodium or lithium reagents 36–38 to produce 39–53.
are used as near-infrared absorbing dyes,1,2 probes,3–5 sensors,6–8
Scheme 2 demonstrates the preparation of quinaldinium
information recording materials,9 emitters,10 and sensitizers.11,12 cyanine dye 57. 6-Hydroxy-2-methylquinoline (54) was allowed
Organic dyes are usually solids because of p–p interactions, hydrogen to react with 2,5,8-trioxa-10-octadecanyl tosylate (10) to give a
bonding, and their strong polarity. Recently, we serendipitously N,O-bis(2,5,8-trioxa-10-octadecanyl) derivative 55, followed by
discovered several neutral-type liquid dyes, coumarins,13 (dialkyl- reaction with triethoxymethane to provide 56, which was treated
amino)perfluorophenazines,14 and azo compounds.15 Recently, with 38 to yield 57. The purity of cyanine dyes was determined
much attention has been paid to ionic liquids, whose chemical via 1H NMR spectroscopy (Fig. S1–S17, ESI†) and elemental
structures consist of heteroaromatic cations and anions. They are analyses.
used as reaction solvents,16–26 electrolytes for secondary batteries27–30
Four liquid cyanine dyes, namely 44, 45, 50, and 51, were
and in dye-sensitised solar cells.31,32 Interestingly, amino acid ionic produced in this study. They were viscous liquids at room
liquids,33 magnetic ionic liquids,34 and herbicidal ionic liquids35 temperature. Even when they were cooled using liquid nitrogen,
have also been reported. On this basis, we wondered whether no crystals and/or powders were formed. Fig. 1a shows the
cationic-type cyanine liquid dyes could be produced since the differential scanning calorimetry (DSC) results of 44. When
structure of cyanine dyes also consists of a cationic heteroaromatic compound 44 was heated from ꢀ50 to 50 1C, a small endothermic
moiety and an anion. To the best of our knowledge, no liquid cyanine peak with a DH of 1.05 kJ molꢀ1 was observed at ꢀ18 1C and no
dyes have been reported so far. As ‘‘liquid dye’’ is a new concept, its peak was observed up to 50 1C. When this compound was cooled
practical applications have not been reported yet. Herein, we report from 50 to ꢀ50 1C, a small exothermic peak was observed at
the survey of a series of liquid cyanine dyes and their properties.
ꢀ24 1C. The second heating–cooling cycle showed similar results
to the first one. Thus, compound 44 was an oil and presented a
glass transition temperature (Tg) of ꢀ18 1C. In contrast, compound
45 exhibited a large endothermic peak at ꢀ9 1C as shown in
Fig. 1b. The shape of the peak in the second cycle was slightly
smaller compared with that in the first cycle. This result suggests
that although the majority of the liquid phase was crystallised by
cooling, a small amount of the amorphous phase still remained.
The heat of fusion was calculated to be 18.3 kJ molꢀ1, which is
significantly larger than that of 44 (1.05 kJ molꢀ1). A freezing point
was clearly observed at ꢀ19 1C. Therefore, the endothermic peak
Results and discussion
Scheme 1 shows the synthesis of cyanine dyes. Methyl-substituted
nitrogen-containing heteroaromatic compounds 1–5 were
Department of Chemistry and Biomolecular Science, Faculty of Engineering,
Gifu University, Yanagido, Gifu 501-1193, Japan. E-mail: matsuim@gifu-u.ac.jp
† Electronic supplementary information (ESI) available: 1H NMR spectra of 23,
39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, and 57 and thermal analyses
data. See DOI: 10.1039/c6nj02160c
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Scheme 1 Conditions and reagents: (i) 1–5 (1.0 equiv.), RY (3.0 equiv.), CHCl3 or toluene, rt, 2 days, (ii) 11–22 (1.0 equiv.), CH(OC2H5)3 (0.6 equiv.),
pyridine, reflux, overnight, (iii) 23–34 (1.0 equiv.), 35–38 (1.5 equiv.), (CH3)2CO–H2O (1 : 1), rt, overnight.
Scheme 2 Conditions and reagents: (i) 54 (1.0 equiv.), NaH (1.1 equiv.), 10 (3.0 equiv.), THF, reflux, 3 h, then 10 (3.0 equiv.), toluene, reflux, overnight,
(ii) 55 (1.0 equiv.), CH(OC2H5)3 (0.6 equiv.), toluene, reflux, overnight, (iii) 56 (1.0 equiv.), 38 (1.5 equiv.), (CH3)2CO–H2O (1 : 1), rt, overnight.
at ꢀ9 1C was assigned to the melting point of 45. Fig. 1c fluorine-containing compounds is lower than those of non-
indicates that compound 50 showed a similar DSC behaviour fluorine-containing derivatives.36 In addition, bulky fluorine-
to 44 with 50 having a Tg at ꢀ22 1C (DH = 1.08 kJ molꢀ1). containing anions can reduce the p–p interactions between the
Compound 51 also showed a similar behaviour to 50 as shown in cations to lower the melting point. Therefore, we prepared
Fig. 1d. Its Tg was observed at ꢀ23 1C with a DH of 0.85 kJ molꢀ1
.
bis(perfluorobutylsulfonyl)imide derivatives to produce liquid
Thus, the cyanine dyes 44, 45, 50, and 51 are liquids at room cyanine dyes.
temperature. Among them, only the liquid 45 displayed melting
Fig. 2b shows the relationship between the melting point or
and freezing points owing to its long octadecyl groups, which Tg and the alkyl substituents on the cyanine dyes that have a
have strong alkyl–alkyl interactions.14,15
bis(perfluorobutylsulfonyl)imide anion. Liquid dyes were
obtained for the dodecyl 44 and octadecyl 45 derivatives. Thier
ꢀ
ꢀ
The effꢀect of the counter anions (Iꢀ, BF4
,
BPh4
,
(CF3SO2)2N , and (C4F9SO2)2Nꢀ) in 1,10-diethylindolenium cya- DSC charts are shown in Fig. 1a and b. The ethyl 42 and octyl 43
nine dyes 23, 39, 40, 41, and 42 on the melting point is shown derivatives were solids (Fig. S22 and S23, ESI†). When the alkyl
in Fig. 2a. Thermal analyses of these dyes are presented in group is short, p–p interactions are dominant. Conversely, the
Fig. S18–S22 (ESI†). The dependence of the melting point on dodecyl and octadecyl groups can weaken and/or inhibit the
the anion is in the order: (C4F9SO2)2Nꢀ (42, 105 1C) o intermolecular interactions to lower the melting point.
(CF3SO2)2Nꢀ (41, 167 1C) o BPh4 (40, 219 1C) o BF4ꢀ, (39,
On the basis of these results, the N,N0-didodecyl heteroaromatic
ꢀ
247 1C) o Iꢀ (23, 267 1C). Usually, the melting points of cyanine dyes with bis(perfluorobutylsulfonyl)imide anions were
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To obtain liquid derivatives, oxyethylene units were introduced
on the nitrogen atoms. The unshared electron pairs on the oxygen
atoms of the oxyethylene unit produce an electronic repulsion,
resulting in less intermolecular interactions, whereas alkyl groups
have van der Waals interactions. The melting points of N,N0-
bis(2,5,8-trioxa-10-octadecanyl) cyanine dyes 50, 51, 52 and 53 are
also indicated in Fig. 2c. As expected, the benzoxazolium and
benzothiazolium derivatives 50 and 51 were liquids with Tgs of
ꢀ22 and ꢀ23 1C, respectively. The DSC curves are shown in Fig. 1c
and d. However, the melting points of quinaldinium 52 and
lepidinium dyes 53 were observed at 46 and 65 1C (Fig. S28 and
S29, ESI†), respectively. The melting point of quinaldinium
cyanine dye 57, in which four oxyethylene units are introduced
in a molecule, was observed at 65 1C (Fig. S30, ESI†), owing to
the wide quinaldinium p-plane.
Fig. 3a and b show the effects of the counter anion and the
alkyl group in indolenium cyanine dyes 23, 39–45 on their
UV-vis absorption and fluorescence spectra in toluene, respectively
(Table 1). No significant differences in the spectra were observed
by changing the counter anions and the alkyl substituents on the
nitrogen atoms. The Stokes shift was small at ca. 20 nm. The
observed fluorescence quantum yield (Ff) ranged from 0.11 to
0.14. The absorption maxima (lmax) of benzoxazolium dyes 46
and 50 were observed at around 498 nm; they were the most
hypsochromic among the indolenium, benzoxazolium, benzo-
thiazolium, quinaldinium, and lepidinium cyanine dyes as
shown in Fig. 3c. The fluorescence maxima (Fmax) of 46 and
50 were observed at 512 and 511 nm, respectively. The Ff of 46
Fig. 1 DSC curves of (a) 44, (b) 45, (c) 50, and (d) 51. A sample (5–7 mg)
was heated from ꢀ50 to 50 1C (10 1C minꢀ1), kept at 50 1C for 2 min,
cooled from 50 to ꢀ50 1C (10 1C minꢀ1), and kept at ꢀ50 1C for 2 min
under a nitrogen atmosphere. This process was repeated again.
Fig. 2 Relationship between the melting point and (a) counter anions, (b) the
number of carbon atoms in R, and (c) heteroaromatic moieties in cyanine dyes.
synthesised to produce a series of liquid cyanine dyes. The
melting points of 46, 47, 48, and 49 were observed at 103, 105,
61, and 80 1C (Fig. S24–S27, ESI†), respectively, as shown in
Fig. 2c. Thus, the N,N0-didodecyl benzoxazolium, benzothiazolium,
quinaldinium, and lepidinium cyanine dyes were solids. This
result can be explained via their planar heteroaromatic moieties,
which enhance p–p interactions compared with indolenium
derivatives wherein two methyl groups attached to the sp3-carbon
provide steric hindrance.
Fig. 3 UV-vis absorption and fluorescence spectra in toluene: (a) 23, 39,
40, 41, and 42 (1.0 ꢁ 10ꢀ5 mol dmꢀ3), (b) 42, 43, 44, and 45 (1.0 ꢁ
10ꢀ5 mol dmꢀ3), (c) 46 and 50 (1.0 ꢁ 10ꢀ6 mol dmꢀ3), (d) 47 and 51 (1.0 ꢁ
10ꢀ6 mol dmꢀ3), (e) 48, 52, and 57 (1.0 ꢁ 10ꢀ6 mol dmꢀ3), and (f) 49 and 53
(1.0 ꢁ 10ꢀ6 mol dmꢀ3).
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Table 1 Physical properties of cyanine dyes
Compd
mp/1C
lmax (e)a/nm
Fmaxa/nm
Ffa
0.12
0.14
0.12
0.12
0.12
0.11
0.12
23
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
57
267
247
219
167
105
68
523 (88 000), 557 (175 000)
524 (75 000), 560 (157 000)
524 (93 000), 559 (174 800)
524 (89 000), 557 (174 000)
523 (89 000), 557 (175 000)
523 (89 000), 557 (174 000)
524 (89 000), 559 (170 000)
525 (86 000), 559 (171 000)
476 (sh), 498 (208 000)
578
581
579
579
578
580
580
580
512
587
630
734
511
583
640
732
654
ꢀ18b
ꢀ9
0.12
0.28
0.19
103
105
61
537 (sh), 575 (185 000)
565 (79 000), 610 (179 000)
660 (48 000), 721 (250 000)
472 (sh), 498 (145 000)
o0.01
80
0.04
ꢀ22b
ꢀ23b
46
0.18
0.16
537 (sh), 576 (119 000)
574 (57 000), 621 (121 000)
659 (34 000), 719 (167 000)
584 (58 000), 636 (114 000)
o0.01
65
65
0.03
o0.01
a
b
Measured on 1.0 ꢁ 10ꢀ5 mol dmꢀ3 of a substrate in toluene. Glass
transition temperature (Tg).
and 50 were observed to be 0.28 and 0.18, respectively.
Benzothiazolium dyes 47 and 51 had their lmax and Fmax at
around 575 and 585 nm in toluene, respectively, as indicated in
Fig. 3d. The Ff values of 47 and 51 were observed to be 0.19 and
0.17, respectively. Fig. 3e depicts that the lmax of quinaldinium
dyes depended on the substituent in the order: N,N0-dodecyl 48
(610 nm) o N,N0-bis(2,5,8-trioxa-10-octadecanyl) 52 (621 nm) o
N,N0,O,O0-tetrakis(2,5,8-trioxa-10-octadecanyl) 57 (636 nm).
Fig. 4 Fluorescence spectra of (a) 42, (b) 44, (c) 45, (d) 46, and (e) 50 in
the crystalline or neat form at 25 and ꢀ196 1C.
This result originates from the electron-donating nature of The fluorescence at ꢀ196 1C was ca. 4.5-times more intense than
the oxyethylene unit. The Fmax of 48, 52, and 57 were observed that at 25 1C. For 45, Fmax was observed at 635 with a Ff of 0.05
at 630, 640, and 654 nm, respectively. The Ff of 48, 52, and 57 at 25 1C. At ꢀ196 1C, Fmax was observed at 647 nm. The
was very small at less than 0.01. The lmax of lepidinium dyes 49 fluorescence was 6.6-times more intense than that at 25 1C.
and 53 were observed at 721 and 719 nm, respectively; they were
Fig. 4d indicates the fluorescence spectra of the solid
amongst the most bathochromic of the cyanine dyes, as shown benzoxazolium dye 46(mp = 103 1C). Fmax was observed at
in Fig. 3f. Their Ff was small at ca. 0.04. The UV-vis absorption 590 nm with a Ff of 0.66. This compound showed a Fmax at
bands of the indolenium, benzoxazolium, benzothiazolium, 588 nm with a similar fluorescence intensity at ꢀ196 1C. Fig. 4e
quinaldinium, and lepidinium cyanine dyes showed a large demonstrates that the liquid derivative 50 showed its Fmax at
first absorption band with a shoulder peak at a short wave- 610 nm with a Ff of 0.25 at 25 1C. At low temperatures, its Fmax
length. The fluorescence spectra were mirror images of the was observed at 605 nm and its fluorescence was 5.4-times
UV-vis absorption spectra. This result indicates that not only more intense.
the S0,0 - S1,0 and S1,0 - S0,0 transitions were observed for the
cyanine dyes in toluene but also the vibrational S0,0 - S1,1 and and 46 were scarcely affected even at ꢀ196 1C, no remarkable
S1,0 - S0,1 transitions were seen. changes in the Fmax and fluorescence intensity were observed.
As the intermolecular interactions of the solid derivatives 42
Interestingly, the liquid dyes 44, 45, and 50 were fluorescent We propose that the shift of Fmax of the liquid derivatives 44,
in their neat form. Therefore, their fluorescence spectra were 45, and 50 at ꢀ196 1C depends on the packing motif formed
compared with those of the corresponding solid derivatives 42 owing to the liquid nitrogen.14 The increase in the fluorescence
and 46 at 25 and ꢀ196 1C (in liquid nitrogen). The solid intensity of the liquid derivatives 44, 45, and 50 at ꢀ196 1C
derivatives 42 and 46 were recrystallized from ethanol. Fig. 4a–c arises from the inhibition of rotational and vibrational processes.
depict the fluorescence spectra of the solid indolenium dye 42 The increase in the fluorescence intensity of fluorophores in
(mp = 105 1C) and its liquid derivatives 44 (Tg = ꢀ18 1C) and 45 solution at low temperatures has been reported previously.37
(mp = ꢀ9 1C), respectively. The Fmax of 42 was observed at 643 nm However, this paper is the first report of the fluorescence of
with a Ff of 0.12 at 25 1C. When the fluorescence spectrum was liquid dyes in their neat form drastically increasing at low
measured at ꢀ196 1C, the Fmax was observed at 643 nm, which is temperatures.
at the same position as observed at 25 1C. The fluorescence
The difference in the solubility between the solid and liquid
intensity increased ca. 1.7-times at ꢀ196 1C. The Fmax of dye 44 indolenium dyes in hexane at room temperature is shown in
was at 636 nm with a Ff of 0.01 at 25 1C. At ꢀ196 1C, Fmax Fig. 5a. Usually, cationic dyes are insoluble in non-polar hexane.
was observed at 648 nm, which constitutes a red-shift of 12 nm. However, the liquid derivative 44 (Tg = ꢀ17 1C) was much more
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obtained using JEOL 400 and 600 spectrometers. Mass spectra
were obtained with a JEOL MStation JMS-700 photometer.
Elemental analysis was performed with a J. Science Lab. CHN
coder JM10. UV-vis absorption and fluorescence spectra were
recorded on Hitachi U-4100 and JASCO FP8600 spectrophoto-
meters, respectively.
Materials
Fig. 5 Solubility of (a) 23, 42, and 44 in hexane, (b) 46 and 50 in propanol,
and (c) 47 and 51 in propanol at 25 1C.
2,3,3-Trimethylindolenine (1), 2-methylbenzoxazole (2), 2-methyl-
benzothiazole (3), 2-methylquinoline (4), 4-methylquinoline (5),
iodoethane (6), 1-iodooctane (7), 1-iododecane (8), 1-iodo-
octadecane (9), sodium tetraphenylborate (36), and triethyl
orthoformate were purchased from TCI Co., Ltd. Tetrafluoro-
boric acid (35) was obtained from Sigma-Aldrich. Lithium
bis(trifluoromethylsulfonyl)imide (37) and lithium bis(perfluoro-
butylsulfonyl)imide (38) were purchased from Wako Chemical
Industries, Ltd. 2,5,8-Trioxa-10-octadecanyl tosylate (10),38 1-ethyl-
2,3,3-trimethyl-3H-indolenium iodide (11),39 2,3,3-trimethyl-1-
octyl-3H-indolenium iodide (12),40 2,3,3-trimethyl-1-octadecyl-3H-
indolenium iodide (14),41 1,10-diethyl-3,3,30,30-tetramethyl-
indolenium cyanine iodide (23),42 and 2-methylquinoline-6-ol
(54)43 were prepared as described in the literature.
soluble in hexane compared to solid derivatives 23 (mp = 267 1C)
and 42 (mp = 105 1C). This result may originate from the weak
intermolecular interactions and affinities of the long alkyl
groups of 42 and 44 with hexane. The oxyethylene derivatives
were insoluble in hexane. However, they were easily soluble in
ether, acetone, and methanol. The difference in the solubility
between the liquid and solid derivatives was also observed in
propanol; Fig. 5b shows that the liquid oxyethylene benzoxazolium
dye 50 (Tg = ꢀ22 1C) was more soluble than the solid derivative 46
(mp = 103 1C). The liquid oxyethylene benzothiazolium dye 51
(Tg = ꢀ23 1C) was also more soluble than the solid derivative 47
(mp = 105 1C) as shown in Fig. 5c.
Synthesis of N-dodecyl iodides 13, 15, 16, 17, and 18
To a chloroform solution (10 mL) of nitrogen-containing hetero-
aromatic compounds 1–5 (10 mmol) was added dodecyl iodide
(8.9 g, 30 mmol) and refluxed for two days. After the reaction
was completed, the mixture was poured into ether. The resulting
precipitate was filtered and washed with ether. The crude
product was dissolved in chloroform and poured into ether.
The resulting precipitate was washed with ether and dried.
1-Dodecyl-2,3,3-trimethyl-3H-indolenium iodide (13). Yield
32%; mp 90–92 1C; 1H NMR (CDCl3) d = 0.88 (t, J = 7.5 Hz, 3H),
1.24–1.29 (m, 14H), 1.36 (quin, J = 7.5 Hz, 2H), 1.45 (quin, J = 7.5
Hz, 2H), 1.67 (s, 6H), 1.94 (quin, J = 7.5 Hz, 2H), 3.13 (s, 3H),
4.67 (t, J = 7.5 Hz, 2H), 7.58–7.60 (m, 3H), 7.66–7.67 (m, 1H);
FABMS (NBA) m/z 328 (M+ ꢀ I).
Conclusions
Liquid indolenium, benzoxazolium, and benzothiazolium cyanine
dyes were synthesised. For the indolenium cyanine dyes, the N,N0-
didodecyl and N,N0-dioctadecyl derivatives that had a bis(perfluoro-
butylsulfonyl)imide anion were liquids at room temperature. Thus,
the medium alkyl-substituted derivatives are liquids, probably owing
to less p–p-interactions. For the benzoxazolium and benzothi-
azolium cyanine dyes, the N,N0-bis(2,5,8-trioxa-10-octadecanyl)
derivatives that had a bis(perfluorobutylsulfonyl)imide anion
were liquids due to the electronic repulsion that comes from
lone-electron pairs on the oxygen atoms. The fluorescence of
the liquid cyanine dyes in their neat form was more intense (4.5–
6.6 times) at ꢀ196 1C than at 25 1C, whereas that of fluorescence of
the solid derivatives showed only a slight intensity increase. This
result can come from the inhibition of rotational and vibrational
processes at ꢀ196 1C. The N,N0-dialkylated liquid indolenium
derivatives were more soluble in hexane than the solid derivatives
due to the weak intermolecular interactions and affinities of the
long alkyl groups with hexane. In addition, the N,N0-bis(2,5,8-trioxa-
10-octadecanyl) liquid benzoxazolium and benzothiazolium deriva-
tives were more soluble in propanol than the solid derivatives. The
concept ‘‘liquid dyes’’ is new, and there are no practical applications
yet. However, for example, liquid dyes have potential applications as
inkjet dyes which need high solubility in solvents.
1-Dodecyl-2-methylbenzoxazolium iodide (15). Yield 22%;
mp 45–47 1C; 1H NMR (CDCl3) d = 0.88 (t, J = 7.6 Hz, 3H),
1.20–1.33 (m, 14H), 1.36 (quin, J = 7.6 Hz, 2H), 1.46 (quin,
J = 7.6 Hz, 2H), 2.02 (quin, J = 7.6 Hz, 2H), 3.42 (s, 3H), 4.75 (t,
J = 7.6 Hz, 2H), 7.75–7.79 (m, 2H), 7.84–7.86 (m, 1H), 7.88–7.90
(m, 1H); FABMS (NBA) m/z 302 (M+ ꢀ I).
1-Dodecyl-2-methylbenzothiazolium iodide (16). Yield 60%;
1
mp 122–124 1C; H NMR (CDCl3) d = 0.88 (t, J = 7.6 Hz, 3H),
1.24–1.30 (m, 14H), 1.36 (quin, J = 7.6 Hz, 2H), 1.48 (quin,
J = 7.6 Hz, 2H), 1.95 (quin, J = 7.6 Hz, 2H), 3.44 (s, 3H), 4.85 (t,
J = 7.6 Hz, 2H), 7.71 (t, J = 8.2 Hz, 1H), 7.82 (t, J = 8.2 Hz, 1H),
8.03 (d, J = 8.2 Hz, 1H), 8.42 (d, J = 8.2 Hz, 1H); FABMS (NBA)
m/z 318 (M+ ꢀ I).
1-Dodecyl-2-methylquinaldinium iodide (17). Yield 12%; mp
93–95 1C; 1H NMR (CDCl3) d = 0.88 (t, J = 7.6 Hz, 3H), 1.22–1.32
(m, 14H), 1.42 (quin, J = 7.6 Hz, 2H) 1.63 (quin, J = 7.6 Hz, 2H),
Experimental
Instruments
DSC and TG/DTA curves were measured with a SII Technology 2.00 (quin, J = 7.6 Hz, 2H), 3.34 (s, 3H), 5.06 (t, J = 7.6 Hz, 2H), 7.90
EXSTAR 6000 thermal analysis system. NMR spectra were (t, J = 8.3 Hz, 1H), 8.12 (d, J = 8.3 Hz, 1H), 8.18 (t, J = 8.3 Hz, 1H),
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8.30 (d, J = 8.3 Hz, 1H), 8.33 (d, J = 8.3 Hz, 1H), 8.98 (d, J = 8.3 Hz,
1H); FABMS (NBA) m/z 312 (M+ ꢀ I).
1,10-Diethyl-3,3,30,30-tetramethylindolenium carbocyanine
iodide (23). Yield 95%; 1H NMR (CDCl3) d = 1.51 (t, J =
1-Dodecyl-2-methyllepidinium iodide (18). Yield 90%; oil; 7.2 Hz, 6H), 1.71 (s, 12H), 4.34 (q, J = 7.2 Hz, 4H), 7.14 (d,
1H NMR (CDCl3) d = 0.87 (t, J = 7.6 Hz, 3H), 1.22–1.24 (m, 14H), J = 8.5 Hz, 2H), 7.25 (t, J = 8.5 Hz, 2H), 7.37 (d, J = 8.5 Hz, 2H),
1.35 (quin, J = 7.6 Hz 2H), 1.50 (quin, J = 7.6 Hz, 2H), 2.10 (quin, 7.38 (t, J = 8.5 Hz, 2H), 7.44 (d, J = 13.3 Hz, 2H), 8.44 (t, J = 13.3
J = 7.6 Hz, 2H), 3.05 (s, 3H), 5.27 (t, J = 7.6 Hz, 2H), 8.03 (t, Hz, 1H); FABMS (NBA) 385 (M+ ꢀ I).
J = 8.2 Hz, 1H), 8.04 (d, J = 5.5 Hz, 1H), 8.26 (t, J = 8.2 Hz, 1H),
3,3,30,30-Tetramethyl-1,10-dioctylindolenium carbocyanine
8.43 (d, J = 8.2 Hz, 1H), 8.45 (d, J = 8.2 Hz, 1H), 10.09 (d, iodide (24). Yield 67%; mp 86–88 1C; 1H NMR (CDCl3) d =
J = 5.5 Hz, 1H); FABMS (NBA) m/z 312 (M+ ꢀ I).
0.86 (t, J = 7.4 Hz, 6H), 1.22–1.40 (m, 16H), 1.56 (quin, J = 7.4 Hz,
4H), 1.71 (s, 12H), 1.88 (quin, J = 7.4 Hz, 4H), 4.28 (t, J = 7.4 Hz,
4H), 7.11 (d, J = 7.8 Hz, 2H), 7.24 (t, J = 7.8 Hz, 2H), 7.36 (d,
J = 7.8 Hz, 2H), 7.37 (t, J = 7.8 Hz, 2H), 7.46 (d, J = 13.6 Hz, 2H),
Synthesis of N-(2,5,8-trioxa-10-octadecanyl) heteroaromatic
tosylates 19–22
To a toluene solution (10 mL) of nitrogen-containing hetero- 8.44 (t, J = 13.6 Hz, 1H); FABMS (NBA) m/z 554 (M+ ꢀ I); anal.
aromatic compounds 1–5 (10 mmol) was added 2,5,8-trioxa-10- found: C, 68.50; H, 8.52; N, 4.10%. Calcd for C39H57IN2: C,
octadecanyl tosylate (9.54 g, 30 mmol) and refluxed for two 68.81; H, 8.44; N, 4.11%.
days. After the reaction was completed, the mixture was poured
into ether. The resulting precipitate was filtered. The crude iodide (25). Yield 70%; mp 36 1C; H NMR (CDCl3) d = 0.87 (t,
product was purified by column chromatography (SiO2, CHCl3 : J = 7.5 Hz, 6H), 1.23–1.28 (m, 28H), 1.36 (quin, J = 7.5 Hz, 4H),
1,10-Didodecyl-3,3,30,30-tetramethylindolenium carbocyanine
1
MeOH = 10 : 1).
1.54 (quin, J = 7.5 Hz, 4H), 1.72 (s, 12H) 1.89 (quin, J = 7.5 Hz,
2-Methyl-1-(2,5,8-trioxa-10-octadecanyl)benzoxazolium tosylate 4H), 4.27 (t, J = 7.5 Hz, 4H), 7.12 (d, J = 7.6 Hz, 2H), 7.25 (t, J = 7.6
1
(19). Yield 5%; oil; H NMR (CDCl3) d = 2.27 (s, 3H), 3.27 (s, 3H), Hz, 2H), 7.33 (d, J = 13.4 Hz, 2H), 7.37 (d, J = 7.6 Hz, 2H), 7.39 (t,
3.32 (s, 3H), 3.42–3.45 (m, 8H), 3.93 (t, J = 4.9 Hz, 2H), 5.12 (t, J = 7.6 Hz, 2H), 8.43 (t, J = 13.4 Hz, 1H); FABMS (NBA) m/z
J = 4.9 Hz, 2H), 7.02 (d, J = 7.9 Hz, 2H), 7.62 (t, J = 7.6 Hz, 1H), 666 (M+ ꢀ I).
7.65 (d, J = 7.9 Hz, 2H), 7.70 (t, J = 7.6 Hz, 1H), 8.09 (d, J = 7.6 Hz,
1,10-Dioctadecyl-3,3,30,30-tetramethylindolenium carbocyanine
1
1H), 8.18 (d, J = 7.6 Hz, 1H); FABMS (NBA) m/z 280 (M+ ꢀ TsO). iodide (26). Yield 72%; mp 11 1C; H NMR (CDCl3) d = 0.88 (t,
2-Methyl-1-(2,5,8-trioxa-10-octadecanyl)benzothiazolium tosylate J = 7.5 Hz, 6H), 1.24–1.29 (m, 52H), 1.37 (quin, J = 7.5 Hz, 4H),
1
(20). Yield 43%; mp 61–63 1C; H NMR (CDCl3) d = 2.27 (s, 3H), 1.54 (quin, J = 7.5 Hz, 4H) 1.74 (s, 12H), 1.88 (quin, J = 7.5 Hz,
3.26 (s, 3H), 3.32 (s, 3H), 3.41–3.46 (m, 8H), 3.93 (t, J = 4.9 Hz, 2H), 4H), 4.23 (t, J = 7.5 Hz, 4H), 7.02 (d, J = 13.7 Hz, 2H), 7.14 (d,
5.12 (t, J = 4.9 Hz, 2H), 7.02 (d, J = 7.9 Hz, 2H), 7.62 (t, J = 7.6 Hz, 1H), J = 7.6 Hz, 2H), 7.27 (t, J = 7.6 Hz, 2H), 7.40 (t, J = 7.6 Hz, 2H),
7.65 (d, J = 7.9 Hz, 2H), 7.70 (t, J = 7.6 Hz, 1H) 8.09 (d, J = 7.6 Hz, 1H), 7.41 (d, J = 7.6 Hz, 2H), 8.44 (t, J = 13.7 Hz, 1H); FABMS (NBA)
8.18 (d, J = 7.6 Hz, 1H); FABMS (NBA) m/z 296 (M+ ꢀ TsO).
m/z 834 (M+ ꢀ I).
2-Methyl-1-(2,5,8-trioxa-10-octadecanyl)quinaldinium tosylate
1,10-Didodecylbenzoxazolium carbocyanine iodide (27). Yield
1
1
(21). Yield 12%; oil; H NMR (CDCl3) d = 2.31 (s, 3H), 3.25 (s, 67%; mp 150 1C; H NMR (CDCl3) d = 0.87 (t, J = 7.6 Hz, 6H),
3H), 3.32 (s, 3H), 3.42–3.70 (m, 8H), 4.13–4.15 (m, 2H), 5.48–5.49 1.23–1.29 (m, 28H), 1.38 (quin, J = 7.6 Hz, 4H), 1.48 (quin,
(m, 2H), 7.09 (d, J = 7.9 Hz, 2H), 7.73 (d, J = 7.9 Hz, 2H), 7.81 (t, J = 7.6 Hz, 4H), 1.92 (quin, J = 7.6 Hz, 4H), 4.27 (t, J = 7.6 Hz, 4H),
J = 7.6 Hz, 1H), 7.84 (d, J = 7.6 Hz, 1H), 8.10 (t, J = 7.6 Hz, 1H), 6.80 (d, J = 13.0 Hz, 2H), 7.28 (d, J = 8.2 Hz, 2H), 7.33 (t,
8.13 (d, J = 7.6 Hz, 1H), 8.58 (d, J = 8.2 Hz, 1H), 8.75 (d, J = 8.2 Hz, 2H), 7.39 (t, J = 8.2 Hz, 2H), 7.47 (d, J = 8.2 Hz, 2H),
J = 8.2 Hz, 1H); FABMS (NBA) m/z 290 (M+ ꢀ TsO).
8.48 (t, J = 13.0 Hz, 1H); FABMS (NBA) m/z 614 (M+ ꢀ I).
2-Methyl-1-(2,5,8-trioxa-10-octadecanyl)lepidinium tosylate
1,10-Didodecylbenzothiazolium carbocyanine iodide (28).
1
1
(22). Yield 69%; oil; H NMR (CDCl3) d = 2.27 (s, 3H), 2.91 (s, Yield 33%; mp 155 1C; H NMR (CDCl3) d = 0.87 (t, J = 7.6 Hz,
3H), 3.31 (s, 3H), 3.43–3.46 (m, 6H), 3.55 (t, J = 4.8 Hz, 2H), 4.03 6H), 1.23–1.29 (m, 28H), 1.35 (quin, J = 7.6 Hz, 4H), 1.54 (quin,
(t, J = 4.8 Hz, 2H), 5.35 (t, J = 4.8 Hz, 2H), 7.06 (d, J = 7.9 Hz, 2H), J = 7.6 Hz, 4H), 1.87 (quin, J = 7.6 Hz, 4H), 4.35 (t, J = 7.6 Hz, 4H),
7.74 (d, J = 7.9 Hz, 2H), 7.84 (d, J = 8.2 Hz, 1H), 7.88 (t, J = 8.2 Hz, 7.28 (d, J = 7.6 Hz, 2H), 7.31 (t, J = 7.6 Hz, 2H), 7.37 (d,
1H), 8.09 (t, J = 8.2 Hz, 1H), 8.25 (d, J = 8.2 Hz, 1H), 8.56 (d, J = 12.4 Hz, 2H), 7.46 (t, J = 7.6 Hz, 2H), 7.69 (d, J = 7.6 Hz,
J = 8.2 Hz, 1H), 9.44 (d, J = 8.2 Hz, 1H); FABMS (NBA) m/z 290 2H), 7.73 (t, J = 12.4 Hz, 1H); FABMS (NBA) m/z 646 (M+ ꢀ I).
(M+ ꢀ TsO).
1,10-Didodecylquinaldinium carbocyanine iodide (29). Yield
Synthesis of cyanine dyes 23–34. To pyridine (5 mL) were 21%; 199 1C; 1H NMR (CDCl3) d = 0.87 (t, J = 7.3 Hz, 6H), 1.26–
added compounds 11–22 (2 mmol) and triethyl orthoformate 1.43 (m, 36H), 1.62–1.79 (m, 4H), 4.27 (br s, 4H), 6.41 (d, J = 12.8
(178 mg, 1.2 mmol). The mixture was refluxed overnight. After Hz, 2H), 7.18 (t, J = 8.2 Hz, 2H), 7.26 (d, J = 7.6 Hz, 2H), 7.40 (d,
cooling, pyridine was removed in vacuo. The product was J = 8.2 Hz, 2H), 7.45 (t, J = 8.2 Hz, 2H), 7.73 (d, J = 9.4 Hz, 2H),
extracted with dichloromethane (50 mL ꢁ 3). The extract was 8.66 (d, J = 9.4 Hz, 2H), 8.70 (t, J = 12.8 Hz, 1H); FABMS (NBA)
dried over anhydrous sodium sulfate. After removing the solvent m/z 634 (M+ ꢀ I).
in vacuo, the product was purified by chromatography (SiO2,
CHCl3 : MeOH = 10 : 1) and recrystallized from ethanol. No 26%; mp 133 1C; H NMR (CDCl3) d = 0.87 (t, J = 7.6 Hz, 6H),
molecular ion peak was observed for 31, 32, 33, and 34 1.24–1.32 (m, 32H), 1.40 (quin, J = 7.6 Hz, 4H), 1.86 (quin,
1,10-Didodecyllepidinium carbocyanine iodide (30). Yield
1
by FABMS.
J = 7.6 Hz, 4H), 4.23 (t, J = 7.6 Hz, 4H), 6.87 (d, J = 13.0 Hz, 2H),
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7.47 (t, J = 7.6 Hz, 2H), 7.51 (d, J = 7.6 Hz, 2H), 7.69 (t, J = 7.6 Hz, 68.32; H, 7.43; N, 5.89%; calcd for C27H33BF4N2: C, 68.65; H,
2H), 7.91 (d, J = 7.6 Hz, 2H), 7.94 (d, J = 7.6 Hz, 2H), 8.24 (d, 7.04; N, 5.93%.
J = 7.6 Hz, 2H), 8.60 (t, J = 13.0 Hz, 1H); FABMS (NBA) m/z
634 (M+ ꢀ I).
1,10-Diethyl-3,3,30,30-tetramethylindolenium carbocyanine
tetraphenylborate (40). Yield 77%; 1H NMR (CDCl3) d = 1.18
1,10-Bis(2,5,8-trioxa-10-octadecanyl)benzoxazolium carbocyanine (t, J = 7.3 Hz, 6H), 1.68 (s, 12H), 3.60 (q, J = 7.3 Hz, 4H), 5.87 (d,
tosylate (31). Yield 51%; 1H NMR (CDCl3) d = 2.31 (s, 3H), 3.33 (s, J = 13.3 Hz, 2H), 6.86 (t, J = 7.3 Hz, 4H), 6.99–7.03 (m, 10H), 7.26
6H), 3.43–3.45 (m, 4H), 3.48–3.52 (m, 8H), 3.59–3.61 (m, 4H), (t, J = 7.3 Hz, 2H), 7.35 (d, J = 7.3 Hz, 2H), 7.39 (t, J = 7.3 Hz, 2H),
3.95 (t, J = 4.8 Hz, 4H), 4.42 (t, J = 4.8 Hz, 4H), 6.66 (d, J = 13.2 Hz, 7.43–7.47 (m, 8H), 8.28 (t, J = 13.3 Hz, 1H); 13C NMR (CDCl3)
2H), 7.13 (d, J = 7.8 Hz, 2H), 7.28 (t, J = 7.6 Hz, 2H), 7.33 (t, d = 12.4 (2C), 27.9 (4C), 39.4 (2C), 49.1 (2C), 103.2 (2C), 110.9
J = 7.6 Hz, 2H), 7.43 (d, J = 7.6 Hz, 2H), 7.46 (d, J = 7.6 Hz, 2H), (2C), 121.7 (4C), 122.1 (2C), 125.46 (2C), 125.52 (8C), 129.0 (2C),
7.85 (d, J = 7.8 Hz, 2H), 8.43 (t, J = 13.2 Hz, 1H).
136.3 (8C), 140.6 (2C), 141.5 (2C), 150.3, 173.2 (2C); in
1,10-Bis(2,5,8-trioxa-10-octadecanyl)benzothiazolium carbo- this compound, no four-carbon peaks assigned to the carbon
1
cyanine tosylate (32). Yield 67%; H NMR (CDCl3) d = 2.35 (s, atoms attached to boron were observed. FABMS (NBA) m/z 385
3H), 3.24 (s, 6H), 3.40–3.42 (m, 4H), 3.44–3.45 (m, 4H), 3.46– (M+ ꢀ BPh4); anal. found: C, 86.64; H, 7.65; N, 3.66%; calcd for
3.48 (m, 4H), 3.54–3.56 (m, 4H), 3.97 (t, J = 4.1 Hz, 4H), 4.60 (t,
J = 4.1 Hz, 4H), 7.14 (d, J = 12.4 Hz, 2H), 7.29 (t, J = 7.8 Hz, 2H),
C
51H53BN2: C, 86.91; H, 7.58; N, 3.97%.
1,10-Diethyl-3,3,30,30-tetramethylindolenium carbocyanine
7.42 (t, J = 7.8 Hz, 2H), 7.43 (d, J = 7.6 Hz, 2H), 7.56 (d, J = 7.8 Hz, bis(trifluoromethylsulfonyl)imide (41). Yield 87%; 1H NMR
2H), 7.57 (d, J = 7.8 Hz, 2H), 7.72 (t, J = 12.4 Hz, 1H), 7.86 (d, (CDCl3) d = 1.45 (t, J = 7.2 Hz, 6H), 1.73 (s, 12H), 4.16 (q, J =
J = 7.6 Hz, 2H).
7.2 Hz, 4H), 6.45 (d, J = 13.4 Hz, 2H), 7.14 (d, J = 7.8 Hz, 2H),
1,10-Bis(2,5,8-trioxa-10-octadecanyl)quinaldinium carbocyanine 7.28 (t, J = 7.8 Hz, 2H), 7.40 (d, J = 7.8 Hz, 2H), 7.41 (t, J = 7.8 Hz,
tosylate (33). Yield 14%; 1H NMR (CDCl3) d = 2.35 (s, 3H), 3.33 (s, 2H), 8.43 (t, J = 13.4 Hz, 1H); 13C NMR (CDCl3) d = 12.4 (2C),
6H), 3.44–3.45 (m, 4H), 3.50–3.52 (m, 4H), 3.54–3.56 (m, 4H), 28.1 (4C), 39.6 (2C), 49.3 (2C), 103.0 (2C), 110.9 (2C), 120.1 (q,
3.62–3.64 (m, 4H), 4.00 (br s, 4H), 4.60 (br s, 4H), 6.56 (d, J = J = 320 Hz, 2C), 122.4 (2C), 125.7 (2C), 129.1 (2C), 140.8 (2C),
13.1 Hz, 2H), 7.17 (d, J = 8.2 Hz, 2H), 7.20 (t, J = 8.2 Hz, 2H), 7.42 141.6 (2C), 150.8, 173.8 (2C); 19F NMR (CDCl3, ext. CFCl3) d =
(d, J = 7.6 Hz, 2H), 7.47 (t, J = 8.2 Hz, 2H), 7.65 (d, J = 8.2 Hz, 2H), ꢀ78.5 (3F); FABMS (NBA) m/z 385 (M+ ꢀ (CF3SO2)2N); anal.
7.67 (d, J = 8.2 Hz, 2H), 7.94 (d, J = 7.6 Hz, 2H), 8.40 (d, J = 8.2 Hz, found: C, 52.14; H, 5.01; N, 6.21%. Calcd for C29H33F6N3O4S2:
2H), 8.70 (t, J = 13.1 Hz, 1H).
C, 52.32; H, 5.00; N, 6.31%.
1,10-Bis(2,5,8-trioxa-10-octadecanyl)lepidinium carbocyanine
1,10-Diethyl-3,3,30,30-tetramethylindolenium carbocyanine
tosylate (34). Yield 19%; 1H NMR (CDCl3) d = 2.32 (s, 3H), 3.31 (s, bis(perfluorobutylsulfonyl)imide (42). Yield 66%; 1H NMR
6H), 3.43–3.44 (m, 4H), 3.50–3.52 (m, 8H), 3.55–3.56 (m, 4H), (CDCl3) d = 1.43 (t, J = 7.2 Hz, 6H), 1.73 (s, 12H), 4.16 (q, J =
3.82–3.84 (m, 4H), 4.39–4.42 (m, 4H), 6.73 (d, J = 13.1 Hz, 2H), 7.2 Hz, 4H), 6.47 (d, J = 13.7 Hz, 2H), 7.14 (d, J = 8.2 Hz, 2H), 7.27
7.16 (d, J = 8.2 Hz, 2H), 7.36–7.38 (m, 4H), 7.60–7.63 (m, 4H), (t, J = 8.2 Hz, 2H) 7.40 (d, J = 8.2 Hz, 2H), 7.41 (t, J = 8.2 Hz, 2H), 8.42
7.71 (d, J = 8.2 Hz, 2H), 7.94 (d, J = 7.6 Hz, 2H), 8.09 (d, J = 8.2 Hz, (t, J = 13.7 Hz, 1H); 13C NMR (CDCl3) d = 12.2 (2C), 27.9 (4C), 39.5
2H), 8.28 (t, J = 13.1 Hz, 1H).
(2C), 49.2 (2C), 102.9 (2C), 110.8 (2C), 122.3 (2C), 125.6 (2C), 129.0
Syntheses of 39–53. To an acetone–chloroform 1 : 1 mixed (2C), 140.7 (2C), 141.6 (2C), 150.7, 173.7 (2C); 19F NMR (CDCl3, ext.
solution (10 mL) of iodides 23–30 or tosylates 31–34 (0.30 mmol) CFCl3) d = ꢀ125.8 (4F), ꢀ120.9 (4F), ꢀ112.7 (4F), ꢀ80.6 (6F); FABMS
were added tetrafluoroboric acid (35), sodium tetraphenylborate (NBA) m/z 385 (M+ ꢀ (C4F9SO2)2N); anal. found: C, 43.45; H, 3.50; N,
(36), lithium bis(trifluoromethylsulfonyl)imide (37), and lithium 4.39%. Calcd for C35H33F18N3O4S2: C, 43.53; H, 3.44; N, 4.35%.
bis(perfluorobutylsulfonyl)imide (38) (0.45 mmol). The mixture
3,3,30,30-Tetramethyl-1,10-dioctylindolenium carbocyanine
was stirred overnight. After the reaction was completed, the bis(perfluorobutylsulfonyl)imide (43). Yield 56%; 1H NMR
solvent was removed in vacuo. The residue was dissolved in (CDCl3) d = 0.86 (t, J = 8.3 Hz, 6H), 1.22–1.30 (m, 12H), 1.34
dichloromethane, purified by column chromatography (SiO2, (quin, J = 8.3 Hz, 4H), 1.44 (quin, J = 8.3 Hz, 4H), 1.70 (s, 12H),
CHCl3 :MeOH = 10:1) and recrystallized from ethanol. Compounds 1.82 (quin, J = 8.3 Hz, 4H), 4.09 (t, J = 8.3 Hz, 4H), 6.42 (d,
44 and 45 were purified by column chromatography (SiO2, C6H14
:
J = 13.7 Hz, 2H), 7.12 (d, J = 7.6 Hz, 2H), 7.27 (t, J = 7.6 Hz, 2H),
CHCl3 = 1:1, CHCl3, and then CHCl3 :MeOH = 10:1). In the case of 7.39 (d, J = 7.6 Hz, 2H), 7.50 (t, J = 7.6 Hz, 2H), 8.42 (t, J = 13.7
42–54, no carbon peaks assigned to the perfluorobutyl group of the Hz, 1H); 13C NMR (CDCl3) d = 14.1 (2C), 22.7 (2C), 26.8 (2C),
counter anion were shown.
27.6 (2C), 28.1 (4C), 29.1 (2C), 29.4 (2C), 31.8 (2C), 44.6 (2C),
1,10-Diethyl-3,3,30,30-tetramethylindolenium carbocyanine 49.3 (2C), 103.2 (2C), 111.2 (2C), 122.3 (2C), 125.6 (2C), 129.0
tetrafluoroborate (39). Yield 59%; H NMR (CDCl3) d = 1.48 (t, (2C), 140.7 (2C), 142.1 (2C), 150.6, 174.1 (2C); 19F NMR (CDCl3,
1
J = 7.6 Hz, 6H), 1.72 (s, 12H), 4.22 (q, J = 7.6 Hz, 4H), 6.81 (d, J = ext. CFCl3) d = ꢀ125.8 (4F), ꢀ120.9 (4F), ꢀ112.6 (4F), ꢀ80.7 (6F);
13.0 Hz, 2H), 7.14 (d, J = 7.7 Hz, 2H), 7.25 (t, J = 7.7 Hz, 2H), 7.37 FABMS (NBA) m/z 554 (M+ ꢀ (C4F9SO2)2N); anal. Found: C,
(d, J = 7.7 Hz, 2H), 7.40 (t, J = 7.7 Hz, 2H), 8.40 (t, J = 13.0 Hz, 50.01; H, 5.17; N, 3.67%. Calcd for C47H57F18N3O4S2: C, 49.78;
1H); 13C NMR (CDCl3) d = 12.5 (2C), 28.0 (4C), 39.7 (2C), 49.0 H, 5.07; N, 3.71%.
(2C), 104.0 (2C), 110.8 (2C), 122.1 (2C), 125.2 (2C), 128.9 (2C),
1,10-Didodecyl-3,3,30,30-tetramethylindolenium carbocyanine
140.7 (2C), 141.8 (2C), 150.9, 173.3 (2C); 19F NMR (CDCl3) d = bis(perfluorobutylsulfonyl)imide (44). Yield 86%; 1H NMR
ꢀ152.7 (4F); FABMS (NBA) m/z 385 (M+ ꢀ BF4); anal. found: C, (CDCl3) d = 0.86 (t, J = 7.6 Hz, 6H), 1.20–1.31 (m, 28H), 1.34
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(quin, J = 7.6 Hz, 4H), 1.44 (quin, J = 7.6 Hz, 4H), 1.72 (s, 12H), (t, J = 7.9 Hz, 2H), 7.30 (d, J = 7.9 Hz, 2H), 7.43–7.51 (m, 4H),
1.81 (quin, J = 7.6 Hz, 4H), 4.10 (t, J = 7.6 Hz, 4H), 6.43 (d, J = 7.68 (d, J = 9.6 Hz, 2H), 8.00 (d, J = 9.6 Hz, 2H), 8.41 (t, J = 12.8
13.1 Hz, 2H), 7.12 (d, J = 7.5 Hz, 2H), 7.26 (t, J = 7.5 Hz, 2H), 7.39 Hz, 1H); 13C NMR (CDCl3) d = 14.1 (2C), 22.7 (2C), 26.6 (2C),
(d, J = 7.5 Hz, 2H), 7.40 (t, J = 7.5 Hz, 2H), 8.41 (t, J = 13.1 Hz, 1H); 27.2 (2C), 29.4 (2C), 29.4 (2C), 29.5 (2C), 29.6 (4C), 29.7 (2C),
13C NMR (CDCl3) d = 14.1 (2C), 22.7 (2C), 26.8 (2C), 27.5 (2C), 31.9 (2C), 47.8 (2C), 104.7 (2C), 115.1 (2C), 120.1 (2C), 124.7
28.0 (6C), 29.4 (4C), 29.6 (6C), 31.9 (2C), 44.5 (2C), 49.2 (2C), (2C), 125.0 (2C), 129.2 (2C), 131.8 (2C), 135.9 (2C), 138.7 (2C),
103.2 (2C), 111.1 (2C), 122.2 (2C), 125.5 (2C), 128.9 (2C), 140.6 147.0, 152.5 (2C); 19F NMR (CDCl3) d = ꢀ125.8 (4F), ꢀ120.8 (4F),
(2C), 142.1 (2C), 150.5, 174.0 (2C); 19F NMR (CDCl3, ext. CFCl3) ꢀ112.7 (4F), ꢀ80.6 (6F); FABMS (NBA) m/z 634 (M+ ꢀ (C4F9SO2)2N);
d = ꢀ125.8 (4F), ꢀ120.9 (4F), ꢀ112.6 (4F), ꢀ80.7 (6F); FABMS anal. found: C, 52.76; H, 5.76; N, 3.43%. Calcd for C53H65N3O4S2:
(NBA) m/z 666 (M+ ꢀ (C4F9SO2)2N); anal. Found: C, 52.96; H, C, 52.43; H, 5.40; N, 3.46%.
6.05; N, 3.31%; calcd for C55H73N3O4S2: C, 53.00; H, 5.90;
N, 3.37%.
1,10-Didodecyllepidinium carbocyanine bis(perfluorobutyl-
sulfonyl)imide (49). Yield 63%; 1H NMR (CDCl3) d = 0.87 (t,
1,10-Dioctadecyl-3,3,30,30-tetramethylindolenium carbocyanine J = 7.1 Hz, 6H), 1.23–1.36 (m, 36H), 1.81 (quin, J = 7.1 Hz, 4H),
bis(perfluorobutylsulfonyl)imide (45). Yield 94%; 1H NMR 4.09 (t, J = 7.1 Hz, 4H), 6.79 (d, J = 13.3 Hz, 2H), 7.43–7.48 (m,
(CDCl3) d = 0.88 (t, J = 7.6 Hz, 6H), 1.24–1.38 (m, 56H), 1.44 6H), 7.59 (d, J = 7.9 Hz, 2H), 7.67 (t, J = 7.9 Hz, 2H), 8.19 (d, J =
(quin, J = 7.6 Hz, 4H), 1.73 (s, 12H), 1.82 (quin, J = 7.6 Hz, 4H), 7.9 Hz, 2H), 8.40 (t, J = 13.3 Hz, 1H); 13C NMR (CDCl3) d = 14.1
4.09 (t, J = 7.6 Hz, 4H), 6.39 (d, J = 13.7 Hz, 2H), 7.12 (d, J = (2C), 22.7 (2C), 26.6 (2C), 29.0 (2C), 29.2 (2C), 29.3 (2C), 29.4
6.9 Hz, 2H), 7.27 (t, J = 6.9 Hz, 2H), 7.39 (d, J = 6.9 Hz, 2H), 7.40 (2C), 29.5 (2C), 29.6 (4C), 31.9 (2C), 54.4 (2C), 109.2 (2C), 110.3
(t, J = 6.9 Hz, 2H), 8.42 (t, J = 13.7 Hz,1H); 13C NMR (CDCl3) (2C), 116.1 (2C), 124.8 (2C), 125.3 (2C), 125.5 (2C), 132.3 (2C),
d=14.1 (2C), 22.7 (2C), 26.8 (2C), 27.5 (2C), 28.0 (6C), 29.4 (4C), 138.1 (2C), 140.1 (2C), 142.5, 159.2 (2C); 19F NMR (CDCl3) d =
29.7 (18C), 31.9 (2C), 44.5 (2C), 49.3 (2C), 103.0 (2C), 111.1 (2C), ꢀ125.7 (4F), ꢀ120.8 (4F), ꢀ112.6 (4F), ꢀ80.6 (6F); FABMS (NBA)
122.2 (2C), 125.6 (2C), 128.9 (2C), 140.6 (2C), 142.1 (2C), 150.5, m/z 634 (M+ ꢀ (C4F9SO2)2N); anal. found: C, 52.73; H, 5.50; N,
174.1 (2C); 19F NMR (CDCl3, ext. CFCl3) d = ꢀ125.8 (4F), ꢀ120.9 3.38%. Calcd for C53H65F18N3O4S2: C, 52.43; H, 5.40; N, 3.46%.
(4F), ꢀ112.6 (4F), ꢀ80.7 (6F); FABMS (NBA) m/z 834 (M+
ꢀ
1,10-Bis(2,5,8-trioxa-10-octadecanyl)benzoxazolium carbocyanine
(C4F9SO2)2N); anal. found: C, 56.66; H, 6.67; N, 2.88%; calcd bis(perfluorobutylsulfonyl)imide (50). Yield 83%; 1H NMR
for C67H97N3O4S2: C, 56.89; H, 6.91; N, 2.97%.
(CDCl3) d = 3.33 (s, 6H), 3.43–3.45 (m, 4H), 3.49–3.50 (m, 4H),
1,10-Didodecylbenzoxazolium carbocyanine bis(perfluorobutyl- 3.51–3.53 (m, 4H), 3.59–3.60 (m, 4H), 3.91 (t, J = 4.8 Hz, 4H), 4.32
sulfonyl)imide (46). Yield 73%; 1H NMR (CDCl3) d = 0.87 (t, (t, J = 4.8 Hz, 4H), 6.19 (d, J = 13.1 Hz, 2H), 7.31 (t, J = 7.6 Hz, 2H),
J = 7.4 Hz, 6H), 1.23–1.45 (m, 36H), 1.85 (quin, J = 7.4 Hz, 4H), 7.36 (t, J = 7.6 Hz, 2H), 7.45 (d, J = 7.6 Hz, 2H), 7.45 (d, J = 7.6 Hz,
4.11 (t, J = 7.4 Hz, 4H), 6.10 (d, J = 13.3 Hz, 2H), 7.26 (d, J = 2H), 8.47 (t, J = 13.1 Hz, 1H); 13C NMR (CDCl3) d = 45.0 (2C), 58.9
8.2 Hz, 2H), 7.32–7.41 (m, 4H), 7.50 (d, J = 8.2 Hz, 2H), 8.47 (t, (2C), 68.3 (2C), 70.3 (2C), 70.4 (2C), 70.6 (2C), 71.8 (2C), 86.2
J = 13.3 Hz, 1H); 13C NMR (CDCl3) d = 14.0 (2C), 22.6 (2C), 26.6 (2C), 110.3 (2C), 112.0 (2C), 124.9 (2C), 125.8 (2C), 132.3 (2C),
(2C), 27.9 (2C), 29.2 (2C), 29.3 (2C), 29.3 (2C), 29.5 (2C), 29.5 146.7 (2C), 148.1, 162.2 (2C); 19F NMR (CD3OD) d = ꢀ125.8 (4F),
(4C), 31.8 (2C), 44.5 (2C), 85.9 (2C), 110.3 (2C), 110.8 (2C), 125.1 ꢀ120.9 (4F), ꢀ112.7 (4F), ꢀ80.7 (6F); FABMS (NBA) m/z 559 (M+
(2C), 126.0 (2C), 121.3 (2C), 146.8 (2C), 148.0, 162.1 (2C); 19F ꢀ (C4F9SO2)2N); anal. found: C, 40.78; H, 3.37; N, 3.42%. Calcd
NMR (CDCl3) d = ꢀ125.8 (4F), ꢀ120.9 (4F), ꢀ112.7 (4F), ꢀ80.7 for C39H41F18N3O12S2: C, 40.74; H, 3.59; N, 3.65%.
(6F); FABMS (NBA) m/z 614 (M+ ꢀ (C4F9SO2)2N); anal. found: C,
1,10-Bis(2,5,8-trioxa-10-octadecanyl)benzothiazolium carbo-
49.65; H, 5.38; N, 3.43%; calcd for C49H61N3O6S2: C, 49.28; H, cyanine bis(perfluorobutylsulfonyl)imide (51). Yield 86%;
5.15; N, 3.52%.
1H NMR (CDCl3) d = 3.33 (s, 6H), 3.41–3.44 (m, 4H), 3.46–3.48
1,10-Didodecylbenzothiazolium carbocyanine bis(perfluoro- (m, 4H), 3.50–3.52 (m, 4H), 3.56–3.58 (m, 4H), 3.95 (t, J = 4.9 Hz,
butylsulfonyl)imide (47). Yield 61%; 1H NMR (CDCl3) d = 0.86 (t, 4H), 4.48 (t, J = 4.9 Hz, 4H), 6.66 (d, J = 12.4 Hz, 2H), 7.32 (t,
J = 6.9 Hz, 6H), 1.23–1.41 (m, 36H), 1.78 (quin, J = 6.9 Hz, 4H), J = 7.6 Hz, 2H), 7.45 (t, J = 7.6 Hz, 2H), 7.57 (d, J = 7.6 Hz, 2H),
4.18 (t, J = 6.9 Hz, 4H), 6.58 (d, J = 12.8 Hz, 2H), 7.21 (d, J = 7.8 7.60 (d, J = 7.6 Hz, 2H), 7.73 (t, J = 12.4 Hz, 1H); 13C NMR
Hz, 2H), 7.31 (t, J = 7.8 Hz, 2H), 7.44 (t, J = 7.8 Hz, 2H), 7.64 (d, (CDCl3) d = 47.6 (2C), 59.0 (2C), 68.5 (2C), 70.3 (2C), 70.5 (2C),
J = 7.8 Hz, 2H), 7.73 (t, J = 12.8 Hz, 1H); 13C NMR (CDCl3) d = 70.8 (2C), 71.9 (2C), 100.0 (2C), 114.6 (2C), 121.8 (2C), 124.8
14.1 (2C), 22.7 (2C), 26.6 (2C), 27.8 (2C), 29.3 (2C), 29.4 (2C), (2C), 125.3 (2C), 127.8 (2C), 142.6 (2C), 147.3, 162.5 (2C);
29.4 (2C), 29.6 (2C), 29.6 (4C), 31.9 (2C), 46.9 (2C), 99.5 (2C), 19F NMR (CDCl3) d = ꢀ125.8 (4F), ꢀ120.9 (4F), ꢀ112.8 (4F),
112.8 (2C), 122.4 (2C), 125.2 (2C), 125.4 (2C), 128.0 (2C), ꢀ80.6 (6F); FABMS (NBA) m/z 601 (M+ ꢀ (C4F9SO2)2N); anal.
141.4 (2C), 147.4, 165.0 (2C); 19F NMR (CDCl3) d = ꢀ125.8 found: C, 40.01; H, 3.83; N, 3.56%. Calcd for C39H41F18N3O10S4:
(4F), ꢀ120.9 (4F), ꢀ112.7 (4F), ꢀ80.7 (6F); FABMS (NBA) m/z C, 39.63; H, 3.50; N, 3.56%.
646 (M+ ꢀ (C4F9SO2)2N); anal. found: C, 47.81; H, 5.42; N,
1,10-Bis(2,5,8-trioxa-10-octadecanyl)quinaldinium carbocyanine
3.36%. Calcd for C49H61F18N3O4S4: C, 47.99; H, 5.01; N, 3.73%. bis(perfluorobutylsulfonyl)imide (52). Yield 54%; 1H NMR (CDCl3)
1,10-Didodecylquinaldinium carbocyanine bis(perfluorobutyl- d = 3.31 (s, 6H), 3.42–3.67 (m, 16H), 3.97 (t, J = 4.9 Hz, 4H), 4.50 (t,
sulfonyl)imide (48). Yield 43%; 1H NMR (CDCl3) d = 0.87 (t, J = 4.9 Hz, 4H), 6.28 (d, J = 12.8 Hz, 2H), 7.16 (t, J = 7.3 Hz, 2H) 7.39
J = 6.6 Hz, 6H), 1.26–1.42 (m, 32H), 1.53–1.60 (m, 4H), 1.80 (d, J = 7.3 Hz, 2H), 7.43 (t, J = 7.3 Hz, 2H), 7.61 (d, J = 7.3 Hz, 2H), 7.66
(br s, 4H), 4.23 (br s, 4H), 6.19 (d, J = 12.8 Hz, 2H), 7.20 (d, J = 9.6 Hz, 2H), 7.91 (d, J = 9.6 Hz, 2H), 8.31 (t, J = 12.8 Hz, 1H);
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13C NMR (CDCl3) d = 47.9 (2C), 58.9 (2C), 68.1 (2C), 70.4 (2C), 4.49 (br s, 4H), 6.38 (d, J = 12.8 Hz, 2H), 6.72 (d, J = 3.2 Hz, 2H),
70.5 (2C), 71.0 (4C), 71.8 (2C), 105.2 (2C), 116.6 (2C), 119.7 (2C), 7.00 (dd, J = 9.6 and 3.2 Hz, 2H), 7.22 (d, J = 8.2 Hz, 2H), 7.49 (d,
124.7 (2C), 124.8 (2C), 128.7 (2C), 131.6 (2C), 136.2 (2C), J = 10.1 Hz, 2H), 7.53 (d, J = 9.6 Hz, 2H), 7.97 (d, J = 8.2 Hz, 2H),
139.7 (2C), 146.5, 152.9 (2C); 19F NMR (CDCl3) d = ꢀ125.7 (4F), 8.30 (d, J = 10.1 Hz, 2H), 8.47 (t, J = 12.8 Hz, 1H); FABMS (NBA)
ꢀ120.8 (4F), ꢀ112.7 (4F), ꢀ80.6 (6F); FABMS (NBA) m/z 589 m/z 914 (M+ ꢀ Tos).
(M+ ꢀ (C4F9SO2)2N); anal. found: C, 44.34; H, 4.18; N, 3.45%.
Synthesis of 1,10-bis(2,5,8-trioxa-10-octadecanyl)-6,60-bis(2,5,8-
trioxa-10-octadecanyloxy)quinaldinium carbocyanine bis(perfluoro-
Calcd for C43H45F18N3O10S2: C, 44.14; H, 3.88; N, 3.59%.
1,10-Bis(2,5,8-trioxa-10-octadecanyl)lepidinium carbocyanine butylsulfonyl)imide (57). To a 1 : 1 acetone–chloroform mixed
bis(perfluorobutylsulfonyl)imide (53). Yield 74%; 1H NMR solution (10 mL) of 56 (150 mg, 0.14 mmol) was added 38
(CDCl3) d = 3.32 (s, 6H), 3.44–3.58 (m, 16H), 3.84 (t, J = 4.8 Hz, (120 mg, 0.21 mmol). The mixture was stirred overnight. After
4H), 4.28 (t, J = 4.8 Hz, 4H), 6.79 (d, J = 12.8 Hz, 2H), 7.28 (d, the reaction was completed, to the residue were added water
J = 7.8 Hz, 2H) 7.43 (t, J = 7.8 Hz, 2H), 7.53 (d, J = 7.8 Hz, 2H), (30 mL) and dichloromethane (30 mL). The organic layer was
7.55 (d, J = 7.8 Hz, 2H), 7.63 (t, J = 7.8 Hz, 2H), 8.15 (d, J = 7.8 Hz, dried over anhydrous sodium sulfate. After removing the
2H), 8.26 (t, J = 12.8 Hz, 1H); 13C NMR (CDCl3) d = 53.6 (2C), 58.9 organic layer in vacuo, the product was dissolved in dichloro-
(2C), 68.3 (2C), 70.5 (4C), 70.8 (2C), 71.8 (2C), 108.4 (2C), 110.6 methane, and purified by column chromatography (SiO2,
1
(2C), 116.3 (2C), 124.7 (2C), 125.2 (2C), 125.6 (2C), 132.4 (2C), CHCl3 : MeOH = 10 : 1). Yield 45%; H NMR (CD3OD) d = 3.28
138.3 (2C), 140.6 (2C), 142.0, 149.1 (2C); 19F NMR (CDCl3) d = (s, 6H), 3.35 (s, 6H), 3.44 (t, J = 4.5 Hz, 4H), 3.52–3.54 (m, 8H),
ꢀ125.7 (4F), ꢀ120.8 (4F), ꢀ112.6 (4F), ꢀ80.6 (6F); FABMS (NBA) 3.59–3.60 (m, 4H), 3.63–3.68 (m, 12H), 3.72–3.73 (m, 4H), 3.88 (t,
m/z 589 (M+ ꢀ (C4F9SO2)2N); anal. found: C, 44.07; H, 4.17; N, J = 4.5 Hz, 4H), 4.00 (t, J = 4.5 Hz, 4H), 4.20 (t, J = 4.5 Hz, 4H),
3.55%. Calcd for C43H45F18N3O10S2: C, 44.14; H, 3.88; N, 3.59%. 4.63 (br s, 4H), 6.43 (d, J = 12.5 Hz, 2H), 7.17 (d, J = 2.8 Hz, 2H),
Synthesis of 2-methyl-1-(2,5,8-trioxa-10-octadecanyl)-6-(2,5,8- 7.28 (dd, J = 9.6 and 2.8 Hz, 2H), 7.74 (d, J = 9.6 Hz, 2H), 7.81 (d,
trioxa-10-octadecanyloxy)quinolinium tosylate (55). To a THF J = 9.6 Hz, 2H), 7.98 (d, J = 9.6 Hz, 2H), 8.42 (t, J = 12.5 Hz, 1H);
solution (10 mL) of 54 (581 mg, 3.6 mmol) were added 60% 19F NMR (CD3OD) d = ꢀ125.1 (4F), ꢀ122.0 (4F), ꢀ114.1 (4F),
sodium hydride (146 mg, 3.7 mmol) and 10 (3.5 g, 11.0 mmol). ꢀ82.3 (6F); FABMS (NBA) m/z 914 (M+ ꢀ (C4F9SO2)2N); anal.
The mixture was refluxed for 3 h. After the reaction was found: C, 45.93; H, 4.74; N, 3.1%. Calcd for C57H73F18N3O18S2:
completed, the solvent was removed in vacuo. To the resulting C, 45.81; H, 4.92; N, 2.81%.
residue were added water (50 mL) and dichloromethane (50 mL).
The organic layer was dried over anhydrous sodium sulfate.
Dichloromethane was removed in vacuo. This crude 2-methyl-6-
(2,5-8-trioxa-10-octadecanyloxy)quinolone was dissolved in
Notes and references
toluene (10 mL). To this solution was added 10 (3.5 g, 11.0 mmol).
The mixture was refluxed overnight. After the reaction was
completed, the mixture was poured into ether. The resulting
precipitate was filtered and purified by column chromatography
(SiO2, CH3Cl : MeOH = 5 : 1). Yield 21%; 1H NMR (CDCl3) d = 2.32
(s, 3H), 3.12 (s, 3H), 3.31 (s, 3H), 3.37 (s, 3H), 3.40–3.42 (m, 8H),
3.55–3.58 (m, 2H), 3.66–3.68 (m, 2H), 3.69–3.72 (m, 2H),
3.75–3.77 (m, 2H), 3.90 (t, J = 4.6 Hz, 2H), 4.04 (t, J = 4.6 Hz,
2H), 4.27 (t, J = 4.6 Hz, 2H), 5.34 (s, 2H), 7.11 (d, J = 8.0 Hz, 2H),
7.51–7.55 (m, 2H), 7.71 (d, J = 8.2 Hz, 1H), 7.78 (d, J = 8.0 Hz,
2H), 8.36 (d, J = 8.2 Hz, 1H), 8.86 (d, J = 8.2 Hz, 1H); FABMS
(NBA) m/z 452 (M+ ꢀ Tos).
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