Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes

Article abstract of DOI:10.1016/j.tet.2019.130512

Mono-, di- and oligo-ether linked (1,8)pyrenophanes 1–7 were synthesized, and their fluorescence and conformational properties in the absence and presence of metal ions were elucidated. Fluorescence spectra of 1.0 × 10^?5 M solutions of the mono- and di-ether linked pyrenophanes 1–5 were comprised of only monomer emission bands, while those of the oligoethylene glycol linked analogs 6 and 7 contained both monomer and intramolecular excimer emission bands. Addition of perchlorate salts of Ba²⁺, Na⁺ and Li⁺ to 1:1 v/v CH₃CN:CH₂Cl₂ solutions of 6 and 7 caused decreases in the intensities of the corresponding intramolecular excimer emission bands and, in some cases, increases in the intensities of the monomer emission. Monomer and intramolecular excimer emission from the (1,8)pyrenophanes are suggested to arise from the respective anti and syn conformers, whose ratios are dependent on solvent polarity, temperature and kinds of added metal ions.

Full text of DOI:10.1016/j.tet.2019.130512

Tetrahedron xxx (xxxx) xxx
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Synthesis, fluorescence properties, and conformational analysis of
ether-linked (1,8)pyrenophanes
Hajime Maeda , Makoto Geshi , Kenji Hirose , Taniyuki Furuyama b, Masahito Segi a
a
,
*
a
a
a,
a
Division of Material Chemistry, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192,
Japan
b
Japan Science and Technology Agency (JST)-PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 17 June 2019
Received in revised form
Mono-, di- and oligo-ether linked (1,8)pyrenophanes 1e7 were synthesized, and their fluorescence and
conformational properties in the absence and presence of metal ions were elucidated. Fluorescence
ꢁ5
spectra of 1.0 ꢀ 10 M solutions of the mono- and di-ether linked pyrenophanes 1e5 were comprised of
31 July 2019
only monomer emission bands, while those of the oligoethylene glycol linked analogs 6 and 7 contained
Accepted 6 August 2019
Available online xxx
2þ
þ
both monomer and intramolecular excimer emission bands. Addition of perchlorate salts of Ba , Na
þ
and Li to 1:1 v/v CH
3
CN:CH
2
Cl
2
solutions of 6 and 7 caused decreases in the intensities of the corre-
sponding intramolecular excimer emission bands and, in some cases, increases in the intensities of the
monomer emission. Monomer and intramolecular excimer emission from the (1,8)pyrenophanes are
suggested to arise from the respective anti and syn conformers, whose ratios are dependent on solvent
polarity, temperature and kinds of added metal ions.
Keywords:
Cyclophane
Pyrene
Pyrenophane
Fluorescence
Excimer
© 2019 Elsevier Ltd. All rights reserved.
1. Introduction
However, in contrast to other pyrenophanes, which have been
subjected to extensive studies, descriptions of the synthesis of (1,8)
Since pyrene has a dual fluorescence character (monomer and
excimer), a high fluorescence quantum yield and photostability, it is
often used as a fluorescence reporter group [1e14]. Pyrenophanes
that contain linked two pyrene moieties have attracted much
attention in view of their characteristic fluorescence properties
pyrenophanes is limited [26] and studies have not been conducted
to assess the equilibrium between their syn and anti conforma-
tional isomers.
The investigation described below focused on the development
of novel fluorescence switching molecules. For this purpose, mono-
, di- and oligo-ether linked (1,8)pyrenophanes 1e7 were synthe-
sized, and their fluorescence properties and conformational pref-
erences were assessed.
(
monomer and intramolecular excimer), structures (plain or bent),
and molecular recognition abilities (guest inclusion) (Scheme 1)
5,15]. (2,7)Pyrenophanes have the highest symmetry and, as a
result, are not capable of existing as conformational isomers
16e25]. In contrast, the pyrene moieties in (1,6)pyrenophanes can
exist in two different orientations that correspond atropisomers
having C2h and D symmetries [21,23,26e31]. In addition, syn and
[
[
2. Results and discussion
2
The pathways employed for the synthesis of (1,8)pyrenophanes
anti conformers are possible for (1,3)pyrenophanes [32e35]. We
have previously demonstrated that equilibrium populations of syn
and anti conformers of oxygen-, sulfur- and selenium-linked
1e7, shown in Scheme 2, began with oxidation of pyrene (8) to form
pyrene-4,5-dione (9) [38,39], which was bis-methylated to produce
,5-dimethoxypyrene (10). Dibromination of 10 at the 1,8-position
40,41] followed by formylation and reduction produced diol 13,
4
[
[3.3](1,3)pyrenophanes are influenced by solvent polarity and
temperature, and that these populations govern their fluorescence
characteristics [36,37]. Like (1,3)pyrenophanes, (1,8)pyrenophanes
also have the capability of existing as syn and anti conformers.
which upon bromination and iodination formed the respective
dibromide 14 and diiodide 15. Pyrenophane 1 was then generated
by reaction of 13 with 14 in the presence of NaH in 7% yield. Pyr-
enophanes 2e7, which possess di- and oligo-ether linkages, were
prepared in 6e18% yields by reactions of 14 or 15 with various diols.
The low yields are a consequence of formation of larger cyclic
*
Corresponding author.
E-mail address: maeda-h@se.kanazawa-u.ac.jp (H. Maeda).
https://doi.org/10.1016/j.tet.2019.130512
040-4020/© 2019 Elsevier Ltd. All rights reserved.
0
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

2
H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
the pyrene chromophore (Fig. S1). Fluorescence spectra of these
solutions differed greatly depending on the nature of the pyr-
enophane linking chains (Fig. 1). Although the fluorescence bands
of 1 occurred at relatively longer wavelength than do those that
arise from monomer emission of common pyrene derivatives
[
10,11], they are attributed to monomer emissions because of their
short fluorescence lifetimes (2.05 ns in CH Cl , 1.02 ns in THF)
Fig. S2). Pyrenophanes 2e5 fluoresced with emission maxima at
2
2
(
ca. 400 nm. Because of their wavelength maxima and shapes, these
bands are also associated with monomer emission. The fluores-
cence of 3 is slightly different from 2, 4, and 5 probably because the
difference in structure or motion of the molecule is involved. The
preference for monomer fluorescence displayed by mono- and di-
ether linked pyrenophanes 1e5 markedly differs from that of 1,
dipyrenylalkanes Py(CH
intramolecular excimer emission [3]. These phenomena are likely a
u-
2
)
n
Py (n ¼ 3e5), which display intense
consequence of ring strain present in 1e5 that prevents formation
of syn conformers in which
pꢁp stacking interactions exist be-
tween the pyrene rings. In addition, the fluorescence bands of 1e5
shifted to longer wavelengths and their intensities decreased with
increasing solvent polarity. This phenomenon is often observed for
monomer emission from methoxy-substituted pyrenes [43,44],
owing to the stabilization effect of more polarized excited states by
more polar solvents. In contrast, both monomer and intramolecular
excimer emission bands existed in fluorescence spectra of 6 and 7.
Moreover, the ratios of the intensities of intramolecular excimer to
monomer emission (Iex/Imon) of 6 and 7 increased with increasing
solvent polarity, seen quantitatively in the plot of Iex/Imon versus
Scheme 1. Conformers of pyrenophanes.
oligomers that were not isolated and characterized. In the reaction
producing 7, the pyrenocrown ether 16 was also formed in 16%
T
E (30) [45] given in Fig. 2. Both 5 and 6 have 9 atoms in chains
yield [42].
UVevis absorption spectra of 1.0 ꢀ 10ꢁ M DMF, CH
5
linking their pyrene rings, however, their fluorescence properties
were significantly different. This might be a consequence of the fact
that the methylene chains in 5 should favor the all-anti confor-
mation while the all-gauche conformation should be favored in the
2 2 3
Cl , CHCl ,
THF and toluene solutions of pyrenophanes 1e7 contained broad
bands in the region of 320e380 nm arising from p-p* transitions of
Scheme 2. Synthesis of (1,8)pyrenophanes 1e7.
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
3
ꢁ
5
Fig. 1. Fluorescence spectra (1.0 ꢀ 10 M) of (a) 1,
ex ¼ 357e359 nm, and (g) 7, ex ¼ 357e359 nm, r.t.
l
ex ¼ 345e347 nm, (b) 2,
l
ex ¼ 357e358 nm, (c) 3,
l
ex ¼ 348e358 nm, (d) 4,
l
ex ¼ 357e359 nm, (e) 5,
l
ex ¼ 357e360 nm, (f) 6,
l
l
T
Fig. 2. Plots of Iex/Imon of (a) 6 and (b) 7 vs E (30).
ꢁ
5
Fig. 3. Variable-temperature fluorescence spectra (1.0 ꢀ 10 M) of 6 in (a) DMF,
ex ¼ 356 nm, and (b) toluene, ex ¼ 359 nm.
corresponding oligoethylene glycol chains in 6 [46,47].
l
l
Information about relationships between preferred conforma-
tions of the pyrenophanes and their emission properties has come
from variable-temperature fluorescence studies of 1e7 in DMF and
toluene (Figs. S3 and S4). Inspection of the fluorescence spectra of
(Fig. S3k,l).
Variable-temperature 1H NMR spectroscopic studies were car-
1
e5 in both DMF and toluene showed that the intensities of the
ried out with 1e7 in DMF-d and toluene-d (Fig. S5). A remarkable
7
8
monomer emission bands increased with decreasing temperature.
Importantly, different behavior was observed for 6 (Fig. 3) where
emission from an intramolecular excimer occurred in DMF
regardless of temperature, whereas in toluene the ratio of mono-
mer to excimer emission intensities increased with decreasing
temperature. A similar temperature dependence of emission was
observed in variable temperature fluorescence studies with 7
temperature effect on any proton resonance was not observed in
the cases of 1e5. In contrast, the resonance for the inner protons in
6 (Fig. 4), marked as Ha in the structure displayed in Scheme 2,
ꢂ
appeared at 8.53 ppm at 40 C in DMF-d and did not change as the
7
ꢂ
temperature was lowered to ꢁ60 C. In contrast, the resonance for
H in the spectrum of 6 in toluene-d shifted downfield from 8.52
a
8
ꢂ
ꢂ
(60 C) to 9.21 ppm (ꢁ80 C) as the temperature was lowered.
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

4
H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
membered crown ether ring systems, it is expected that they would
form host-guest complexes with metal ions perhaps in a size se-
lective manner [48e54]. In order to explore this proposal, fluo-
rescence changes were monitored upon addition of perchlorate
3 2 2
salts of various metal ions to 1:1 v/v CH CN:CH Cl solutions of 6
and 7 (Fig. 5aef). In the case of 6, addition of metal salts caused a
decrease in the intensity of the intramolecular excimer emission
band and a simultaneous increase in the intensity of monomer
emission along with the existence of isoemissive points. The degree
2þ
þ
þ
of the change decreased in the order of Ba >Na >Li . The change
from intramolecular excimer to monomer emission of pyrenophane
2
þ
7
, which has a larger ring size, was large when Ba cation was
þ
þ
present, whereas when Na and Li were present the intensity of
intramolecular excimer emission decreased to a lesser extent and
monomer emission was unaltered. Analysis of Job's plots [55e57],
constructed using the absorption and fluorescence spectroscopic
changes, indicated that 6 and 7 form 1:1 complexes as the major
species with all of these metal cations (Fig. 5g and h). Inspection of
complexation constants K [58] obtained from analysis of the fluo-
rescence changes showed that K values for complexation of metal
2
þ
þ
þ
ions to 6 and 7 decrease in the order of Ba >Na >Li and that 7
2þ
binds Ba more strongly than does 6 (Table 1).
Information about structural changes occurring in association
with interactions between the pyrenophanes and metal cations
1
came from H NMR analysis of CDCl
3
solutions of 6 and 7 before and
to
solution of 6 promoted a downfield shift of the resonance
4 2
after addition of metal perchlorates (Fig. 6). Addition of Ba(ClO )
a CDCl
for H
3
a
4
from 8.39 to 8.93 ppm, while addition of NaClO resulted in a
slight upfield shift from 8.39 to 8.33 ppm. Similarly, addition of
Fig. 4. Variable-temperature 1H NMR (500 MHz) spectra of 6 in (a) DMF-d
and (b)
7
8
toluene-d .
Table 1
Ionic radii and complexation constants for metal ions.
Similar changes in the chemical shift of the resonance for H
a
ionic radius (pm)a
K (Mꢁ1)b
metal ion
ꢂ
ꢂ
(
8.45 ppm at 40 C, 8.61 ppm at ꢁ80 C) were observed in
a
1
6
7
variable-temperature H NMR spectroscopic study of 7 in toluene-
. The combined results arising from the variable-temperature
Ba2
þ
þ
135
95
60
775 ± 15
286 ± 14
162 ± 7
9060 ± 290
272 ± 13
166 ± 11
d
8
1
Na
fluorescence and H NMR spectroscopic studies suggest that the
resonance of H of excimer-emitting syn form appears at upfield,
þ
Li
a
a
Data from Ref. [59].
and that of monomer-emitting anti form appears at downfield.
Because pyrenophanes 6 and 7 possess respective 30 and 36
b
Complexation constants calculated by using TitrationFit 2014-0630 based on
fluorescence changes.
Fig. 5. Fluorescence spectra of (a)e(c) 6,
l
ex ¼ 358 nm, and (d)e(f) 7,
2þ
l
ex ¼ 357 nm, upon addition of (a)(d) Ba(ClO
4
)
2
, (b)(e) NaClO
4
, and (c)(f) LiClO
4
, in 1:1 CH
3
CN:CH
2 2
Cl , [6 or
ꢁ
5
2þ
ꢁ5
7
] ¼ 1.0 ꢀ 10 M, r.t. (g) Job's plot for complexation of 6 with Ba obtained from change of fluorescence intensity at 408 nm, [6] þ [Ba ] ¼ 1.0 ꢀ 10 M, r.t.,
l
ex ¼ 358 nm. (h) Job's
2þ
2þ
ꢁ5
plot for complexation of 7 with Ba obtained from change of absorbance at 357 nm, [7] þ [Ba ] ¼ 1.0 ꢀ 10 M, r.t.
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
5
fact that the dipole moment contributions from the pyrene rings in
the syn form are additive, whereas in the anti conformer those from
the pyrene rings are subtractive. Consequently, polar solvents sta-
0 1
bilize the ground state (S ) of syn-6. Also, the excited state (S ) of
the syn conformer can form an intramolecular excimer, which
relative to that of the anti-conformer, is stabilized by polar solvents
such as DMF. Finally, the observed increase in the ratio of intra-
molecular excimer to monomer emission at higher temperatures in
toluene, might also be related to an entropy increase arising from
desolvation, a decrease in solvent viscosity [60], fluorescence life-
time [61,62] and an increase in molecular motion. Similar tem-
perature dependency is also found in pyrene (8) [2] and 1,3-di(1-
pyrenyl)propane [63,64].
(
1,8)Pyrenophanes 6 and 7 containing crown ether moieties
exist as equilibrium mixtures of syn and anti conformers (Scheme
). Addition of metal cations to solutions of 6 and 7 leads to host-
3
1
guest complex formation and fluorescence and H NMR spectral
changes. Inspection of the fluorescence results suggest that struc-
tures of the formed complexes differ depending on the sizes of
crown ether ring systems and metal cations. The findings indicate
that 6 forms M @anti type complexes preferentially with all three
metal cations while 7 forms a M @anti type complex with Ba
Fig. 6. 1H NMR (500 MHz, CDCl
þ excess NaClO , (d) 7, (e) 7 þ excess Ba(ClO
3
) spectra of (a) 6, (b) 6 þ excess Ba(ClO
4 2
) , (c)
nþ
6
4
4
)
2
, and (f) 7 þ excess NaClO , r.t.
4
nþ
2þ
nþ
þ
þ
and M @syn type complexes with Na and Li [65]. The spectral
þ
þ
Ba(ClO
4
)
2
to a CDCl
3
solution of 7 caused a downfield shift of H
induced an upfield
a
changes in fluorescence upon addition of Na or Li to solutions of
7 may indicate that the fluorescence intensities of the complexes
are smaller than that of the uncomplexed substrate.
from 8.32 to 8.89 ppm, while addition of NaClO
4
shift from 8.32 to 8.08 ppm. Combined inspection of increase of
monomer emission and the downfield shift upon addition of
Ba(ClO ) showed again that resonance of H of anti conformer
4 2 a
appears more downfield than that of syn conformer.
3. Conclusion
Optimized structures of syn and anti conformers of 6 and of the
transition state (TS) in interconversion of the conformers were
estimated using DFT calculations with a B3LYP/6-311G basis set
In the study described above, we prepared seven novel ether-
1
linked (1,8)pyrenophanes and probed their fluorescence and
H
(
Fig. 7). The results show that anti-6 is 26.2 kJ/mol more stable than
syn-6. The inner protons H in syn-6 (marked in Fig. 7) were upfield
shifted as a consequence of ring current effect of the opposing
pyrene ring. In contrast, H of anti-6 did not experience a ring
current effect. Because the distance between H and the other
pyrene ring in syn form is larger in 7 than that in 6, the ring current
effect on the chemical shift of H in 7 is lower. Dipole moments of
NMR in order to gain information about their conformational
characteristics and metal cation binding properties. In contrast to
the mono- and di-ether linked pyrenophanes 1e5 that displayed
only monomer-type fluorescence, the oligo-ether tethered sub-
stances 6 and 7 displayed both monomer and intramolecular
excimer emissions. We observed that solvent, temperature and
metal cation binding change the ratios of the intensities of the
monomer- and intramolecular exciplex-emission in a manner that
is consistent with changes in equilibria between the syn and anti
conformers of these substances in the ground, singlet excited and
a
a
a
a
syn-6 and anti-6 were determined to be 5.8 and 0.015 D, respec-
tively. This finding is reasonable when consideration is given to the
0 1
Fig. 7. Energy profiles in interconversion of anti-6 and syn-6 in the ground (S ) and singlet excited (S ) states, calculated by using DFT and a B3LYP/6-311G basis set.
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

6
H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
Scheme 3. Equilibria between anti-6,7 and syn-6,7 and their metal complexes.
metal cation complexed states. We anticipate that the emission
switching pyrenophanes 6 and 7 will be models for the design of
new fluorescence sensors for metal cations.
aqueous layers, and the aqueous layer was washed with CH
(50 mL ꢀ 3). The combined organic layers were washed with satu-
rated NaCl aqueous solution, dried over Na SO , filtered, and
concentrated in vacuo, giving a residue that was subjected to silica
gel column chromatography ( Cl
¼ 0.3) to give pyrene-4,5-dione (9, reddish orange solid, 2.99 g,
5% yield). Lit [38,39].
To a stirred H O (50 mL) and THF (50 mL) solution of pyrene-4,5-
dione (9, 1.758 g, 7.6 mmol) were added n-Bu NBr (0.79 g,
.45 mmol) and Na (4.27 g, 24.5 mmol), and the resulting
solution was stirred at room temperature for 5 min. To the solution
were added NaOH aqueous solution (2.5 M, 40 mL) and Me SO
5.17 g, 41 mmol), and the mixture was stirred at room temperature
2 2
Cl
2
4
f
¼ 5 cm, l ¼ 15 cm, eluent: CH
2
2
,
4
. Experimental section
R
4
f
4.1. Materials and equipments
2
4
Et
C ¼ O. CH
. DMF was distilled without drying agent. Spectral grade
, CH Cl , and DMF were purchased and used for spectro-
2
O and THF were distilled from CaH
2
and then from Na/
2
2 2 4
S O
Ph
2
2
Cl , CHCl , toluene, EtOH, and CH
2
3
3
CN were distilled
from CaH
of CHCl
2
2
4
3
2
2
(
scopic studies without further purification. Most other chemical
substances were used after purification by distillation or recrys-
2
for 12 h and extracted with Et O (50 mL). The aqueous layer was
1
13
washed with Et
washed with H O (50 mL) and then with saturated NaCl aqueous
solution (50 mL), dried over Na SO , filtered, and concentrated in
vacuo, giving a residue that was subjected to silica gel column
chromatography ( , R ¼ 0.8) to
¼ 5 cm, l ¼ 15 cm, eluent: CHCl
give 4,5-dimethoxypyrene (10, ocher solid, 1.81 g, 92% yield). Lit
40].
To an argon-purged, stirred CH
dimethoxypyrene (10, 1.004 g, 3.8 mmol) Br
0.44 mL, 8.4 mmol), and the resulting solution was stirred at room
2
O (30 mL). The combined organic layers were
tallization. H and C NMR spectra were recorded using a JEOL JMN
LA-400 (400 MHz and 100 MHz, respectively) or a JEOL ECA-500
2
2
4
(
4
500 MHz and 125 MHz, respectively) spectrometer with Me Si as
an internal standard. IR spectra were determined using a Shimadzu
FTIR-8300 spectrometer. Low- and high-resolution mass spectra
were taken on a JEOL JMS-AM50 and a JEOL JMS-SM102A instru-
ment, respectively. UVevis spectra were recorded using a Hitachi
U-2900 spectrophotometer. Fluorescence spectra were recorded
using a Jasco FP-8500 spectrophotometer. The fluorescence life-
times of 1 were measured with a picosecond light pulser (Hama-
matsu Photonics C4725, 408 nm, 59 ps FWHM) and a streak-scope
f
3
f
[
2
Cl
2
(20 mL) solution of 4,5-
was added dropwise
2
(
temperature for 5 min. NaOH aqueous solution (20%, 20 mL) was
added and the formed precipitate was collected by filtration and
characterized as the product 11. The filtrate was extracted with
(
Hamamatsu Photonics C4334-02). HPLC separations were per-
formed on recycling preparative HPLC instrument (Japan
a
CH
30 mL ꢀ 2). The combined organic layers were washed with NaCl
aqueous solution (50 mL), dried over Na SO filtered, and
concentrated in vacuo, giving a residue that was subjected to silica
gel column chromatography ( Cl
¼ 5 cm, l ¼ 15 cm, eluent: CH
¼ 0.95) to give 1,8-dibromo-4,5-dimethoxypyrene (11, white
solid, 1.41 g, 87% yield). Lit [40].
2 2 2 2
Cl (50 mL). The aqueous layer was washed with CH Cl
Analytical Industry Co. Ltd., LC-908 equipped with a JAIGEL-H (GPC)
column). Column chromatography was conducted by using Kanto-
Chemical Co. Ltd., silica gel 60 N (spherical, neutral, 0.04e0.05 mm).
Thin-layer chromatography was performed with Merck Kiesel gel
(
2
4
,
f
2
2
,
6
0 F254 plates, and spots were detected by using UV light and a
R
f
phosphomolybdic acid ethanol solution with heating. Theoretical
calculations were performed by using B3LYP/6-311G basis set in a
Gaussian 09 software package. Complexation constants were
calculated by using TitrationFit 2014-0630 based on changes of UV
absorption and fluorescence spectra.
To an argon-purged, stirred THF (120 mL) solution of 1,8-
dibromo-4,5-dimethoxypyrene (11, 1.890 g, 4.5 mmol) was added
ꢂ
slowly tert-BuLi (1.6 M in pentane, 16 mL, 25 mmol) at ꢁ78 C, and
ꢂ
the resulting solution was stirred at ꢁ78 C for 1 h. To the solution
was added slowly DMF (0.733 g, 10 mmol), and the resulting solu-
4.2. Preparation of 1,8-bis(hydroxymethyl)-4,5-dimethoxypyrene
tion was stirred at room temperature for 1 h. H
slowly added and the resulting solution was extracted with CH
50 mL). The aqueous layer was washed with CH Cl
The combined organic layers were washed with HCl aqueous so-
lution (1 N, 50 mL) and then with saturated NaCl aqueous solution
2
O (150 mL) was
Cl
(50 mL ꢀ 3).
(13)
2
2
(
2
2
To a stirred CH
8, 6.068 g, 30 mmol) were added NaIO
120 mL), and RuCl O (0.1 g, 0.4 mmol). The mixture was stir-
ꢃnH
2
Cl
2
(90 mL) and THF (90 mL) solution of pyrene
(
(
4
(21.4 g, 100 mmol), H O
2
3
2
2 4
(50 mL), dried over Na SO , filtered, and concentrated in vacuo to
red at room temperature for 24 h and filtered through silica gel
using CH Cl (200 mL). The filtrate was divided into organic and
give a solid that was washed with acetone and collected by
2
2
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
7
þ
filtration to give 1,8-diformyl-4,5-dimethoxypyrene (12, 1.10 g, 75%
(100), 288 (32), 415 (24), 542 (2, M ); HRMS (EI) calcd for
20 16 2 2
C H I O : 541.9240, found: 541.9296.
ꢂ
1
yield). Data for 12: dark yellow solid; mp 219e222 C; H NMR
400 MHz, CDCl
4.27 (s, 6H), 8.54 (d, J ¼ 8.0 Hz, 2H), 8.71 (d,
J ¼ 8.0 Hz, 2H) 9.56 (s, 2H), 10.82 (s, 2H) ppm; C NMR (100 MHz,
CDCl 61.42, 120.66,122.36,126.09, 128.00, 129.92, 131.88,132.95,
46.55, 192.71 ppm; IR (KBr) 1026, 1203, 1492, 1612, 1685,
(
3
) d
13
4.5. Preparation of pyrenophane 1
3
) d
1
2
2
A mixture of 1,8-bis(hydroxymethyl)-4,5-dimethoxypyrene (13,
0.16 g, 0.5 mmol) and NaH (60% in mineral oil, 0.8 g, 20 mmol) in
THF (120 mL) was stirred at room temperature for 1 h under an
argon atmosphere. To the solution was added dropwise a THF
(45 mL) solution of 1,8-bis(bromomethyl)-4,5-dimethoxypyrene
(14, 0.26 g, 0.5 mmol) over a 2 h period, and the resulting solution
was stirred at reflux for 3 days. Ice water (50 mL) was slowly added.
ꢁ
1
742 cm ; MS (EI) m/z (relative intensity, %) ¼ 198 (1), 231 (13),
þ
59 (10), 275 (7), 303 (27), 318 (100, M ); HRMS (EI) calcd for
C
H
20 14
O
4
: 318.0892, found: 318.0897.
To
a
stirred THF (60 mL) solution of 1,8-diformyl-4,5-
dimethoxypyrene (12, 0.79 g, 2.5 mmol) were added NaBH
4
ꢂ
(
0.39 g, 10.2 mmol) and EtOH (6 mL) at 0 C, and the mixture was
ꢂ
stirred at 0 C for 1 h. HCl (1 N, 50 mL) was slowly added. The so-
lution was extracted with Et O (40 mL) and the aqueous layer was
washed with Et O (30 mL). The combined organic layers were
washed with saturated NaCl aqueous solution (40 mL), dried over
Na SO , filtered, and concentrated in vacuo to give a solid that was
washed with CHCl and collected by filtration to give 1,8-
bis(hydroxymethyl)-4,5-dimethoxypyrene (13, 0.58 g, 72% yield).
The solution was extracted with CHCl
layer was washed with CHCl
(50 mL ꢀ 3). The combined organic
layers were washed with saturated NaCl aqueous solution (50 mL),
dried over Na SO , filtered, and concentrated in vacuo, giving a
residue that was subjected to silica gel column chromatography
3
(50 mL) and the aqueous
2
3
2
2
4
2
4
3
(f
¼ 3 cm, l ¼ 15 cm, eluent: CHCl :EtOH ¼ 30:1, R ¼ 0.4) followed
by recycling preparative HPLC (GPC, eluent: CHCl
7,8,20,21-tetramethoxy-2,15-dioxa[3.3](1,8)pyrenophane
0.010 g, 7% yield). Data for 1: pale yellow solid; mp 234e236 C; H
NMR (400 MHz, CDCl 4.22 (s, 12H), 5.16 (s, 8H), 7.48 (s, 4H), 8.02
3
f
3
) to give
ꢂ
1
Data for 13: yellow solid; mp 160e164 C; H NMR (400 MHz,
CDCl
1.58 (brs, 2H), 4.21 (s, 6H), 5.43 (s, 4H), 8.10 (d, J ¼ 8.0 Hz,
H), 8.47 (s, 2H), 8.48 (d, J ¼ 8.0 Hz, 2H) ppm; C NMR (100 MHz,
CDCl 61.18, 63.84, 119.42, 123.42, 123.54, 126.37, 128.57, 128.66,
33.61, 144.52 ppm; IR (KBr) 961, 1103, 1196, 1227, 1304, 1396, 1612,
(1,
ꢂ
1
3
)
d
13
2
3
) d
13
3
)
d
(d, J ¼ 8.0 Hz, 4H), 8.40 (d, J ¼ 8.0 Hz, 4H) ppm; C NMR (100 MHz,
1
2
CDCl
3
)
d
61.22, 70.53, 118.53, 123.35, 124.99, 128.56, 129.70, 131.74,
ꢁ
1
ꢁ1
847, 3344 cm ; MS (EI) m/z (relative intensity, %) ¼ 44 (7), 77 (13),
144.64, 169.74 ppm; IR (KBr) 1230, 1500, 1604, 2854, 2927 cm
;
þ
105 (6), 149 (12), 218 (10), 231 (17), 307 (35), 322 (100, M ); HRMS
MS (EI) m/z (relative intensity, %) ¼ 260 (6), 288 (8), 320 (4), 608
þ
(
EI) calcd for C20
18
H O
4
: 322.1205, found: 322.1209.
(100, M ); HRMS (EI) calcd for C40
H
32
O
6
: 608.2199, found:
608.2219.
4.3. Preparation of 1,8-bis(bromomethyl)-4,5-dimethoxypyrene
(14)
4.6. Preparation of pyrenophane 2
To an argon-purged, stirred Et
bis(hydroxymethyl)-4,5-dimethoxypyrene (13, 0.805 g, 2.5 mmol)
was added a CHCl (10 mL) solution of PBr (2.3 g, 8.4 mmol). The
resulting solution was stirred at room temperature for 24 h. Satu-
rated NH Cl aqueous solution (30 mL) was added, and the solution
was stirred at room temperature for 10 min. H O (20 mL) was
added. The solution was extracted with CH Cl (30 mL) and the
aqueous layer was washed with CH Cl
(30 mL ꢀ 3). The combined
organic layers were washed with saturated NaCl aqueous solution
30 mL), dried over Na SO , filtered, and concentrated in vacuo to
give 1,8-bis(bromomethyl)-4,5-dimethoxypyrene (14, 0.764 g, 68%
2
O (50 mL) solution of 1,8-
A mixture of ethylene glycol (0.068 g, 1.1 mmol) and NaH (60% in
mineral oil, 0.8 g, 20 mmol) in THF (100 mL) was stirred at reflux for
1 h under an argon atmosphere. To the solution was added drop-
3
3
wise
a THF (40 mL) solution of 1,8-bis(bromomethyl)-4,5-
4
dimethoxypyrene (14, 0.448 g, 1.0 mmol) over a 1 h period, and
the resulting solution was stirred at reflux for 3 days. Ice water
2
2
2
(30 mL) was slowly added. The solution was extracted with CH
(30 mL) and the aqueous layer was washed with CH
2
Cl
Cl
2
2
2
2
2
(30 mL ꢀ 3). The combined organic layers were washed with satu-
rated NaCl aqueous solution (30 mL), dried over Na SO , filtered,
and concentrated in vacuo, giving a residue that was subjected to
silica gel column chromatography (
¼ 3 cm, l ¼ 15 cm, eluent:
CH Cl ¼ 0.3) followed by recycling preparative
:EtOH ¼ 30:1, R
HPLC (GPC, eluent: CHCl ) to give 10,11,26,27-tetramethoxy-
2,5,18,21-tetraoxa[6.6](1,8)pyrenophane (2, 0.049 g, 14% yield).
(
2
4
2
4
ꢂ
1
yield). Data for 14: yellow solid; mp 204e207 C (dec); H NMR
400 MHz, CDCl
f
(
8
d
3
)
d
4.19 (s, 6H), 5.25 (s, 4H), 8.05 (d, J ¼ 8.0 Hz, 2H),
2
2
f
13
.46 (d, J ¼ 8.0 Hz, 2H), 8.51 (s, 2H) ppm; C NMR (100 MHz, CDCl
3
)
3
31.81, 61.21, 119.83, 123.37, 123.59, 128.19, 128.70, 129.35, 130.78,
ꢁ
1
ꢂ
1
1
44.93 ppm; IR (KBr) 640, 1230, 1500, 1604, 2842, 2935 cm ; MS
Data for 2: ocher solid; mp 232e234 C; H NMR (500 MHz, CDCl
3
)
(
(
4
EI) m/z (relative intensity, %) ¼ 226 (68), 288 (100), 367 (68), 448
d
3.96 (s, 8H), 4.17 (s, 12H), 5.22 (s, 8H), 7.97 (d, J ¼ 7.5 Hz, 4H), 8.40
þ
13
13, M ); HRMS (EI) calcd for C20
H16Br
2
O
2
: 447.9497, found:
(d, J ¼ 8.0 Hz, 4H), 8.79 (s, 4H) ppm; C NMR (100 MHz, CDCl
61.13, 70.92, 72.65, 118.88, 118.91, 124.40, 127.64, 128.61, 129.51,
29.53, 131.18, 131.21, 144.44 ppm; IR (KBr) 1226, 1465, 1608, 2881,
3
)
47.9498.
d
1
ꢁ
1
4
.4. Preparation of 1,8-bis(iodomethyl)-4,5-dimethoxypyrene (15)
2950 cm ; MS (FABþ) m/z (relative intensity, %) ¼ 289(28),
3
49(11), 409(3), 697(48); HRMS (FABþ) calcd for C44
41 8
H O :
To an argon-purged, stirred CH
bis(hydroxymethyl)-4,5-dimethoxypyrene (13, 0.161 g, 1 mmol)
were added NaI (0.45 g, 3 mmol) and Me SiCl (0.32 g, 3 mmol), and
the resulting solution was stirred at room temperature for 30 min
66]. H O (20 mL) was added. The formed bright yellow solid was
collected by filtration with CH CN to give 1,8-bis(iodomethyl)-4,5-
3
CN (10 mL) solution of 1,8-
697.2801, found: 697.2792.
3
4.7. Preparation of pyrenophane 3
[
2
A mixture of 1,3-propanediol (0.084 g, 1.1 mmol) and NaH (60%
in mineral oil, 0.8 g, 20 mmol) in THF (100 mL) was stirred at reflux
for 1 h under an argon atmosphere. To the solution was added
dropwise a THF (40 mL) solution of 1,8-bis(bromomethyl)-4,5-
dimethoxypyrene (14, 0.448 g, 1.0 mmol) over a 1 h period, and
the resulting solution was stirred at reflux for 3 days. Ice water
3
dimethoxypyrene (15, 0.178 g, 65% yield). This product is unstable
under air at room temperature and undergoes decomposition to
produce a black residue within 3 days. Data for 15: mp 147e152 C
ꢂ
1
(
dec); H NMR (400 MHz, CDCl
3
)
d
4.18 (s, 6H), 5.22 (s. 4H), 8.06 (d,
J ¼ 8.0 Hz, 2H), 8.42 (d, J ¼ 8.0 Hz, 2H), 8.51 (s, 2H) ppm; IR (KBr)
(30 mL) was slowly added. The solution was extracted with CH
(30 mL) and the aqueous layer was washed with CH
2
Cl
Cl
2
ꢁ
1
1
226, 1497, 1604, 2935 cm ; MS (EI) m/z (relative intensity, %) ¼ 83
2
2
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

8
H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
þ
(
30 mL ꢀ 3). The combined organic layers were washed with satu-
%) ¼ 226 (2), 288 (9), 780 (15, M ); HRMS (FABþ) calcd for
50 52 8
C H O : 780.3662, found: 780.3659.
rated NaCl aqueous solution (30 mL), dried over Na
2
SO
4
, filtered,
and concentrated in vacuo, giving a residue that was subjected to
silica gel column chromatography (
¼ 3 cm, l ¼ 15 cm, eluent:
CH Cl ¼ 0.3) followed by recycling preparative
:EtOH ¼ 30:1, R
HPLC (GPC, eluent: CHCl ) to give 11,12,28,29-tetramethoxy-
,6,19,23-tetraoxa[7.7](1,8)pyrenophane (3, 0.064 g, 18% yield).
f
2
2
f
4.10. Preparation of pyrenophane 6
3
2
A mixture of diethylene glycol (0.106 g, 1.0 mmol) and NaH (60%
in mineral oil, 0.8 g, 20 mmol) in THF (100 mL) was stirred at room
temperature for 1 h under an argon atmosphere. To the solution
ꢂ
1
Data for 3: ocher solid; mp 181e182 C; H NMR (500 MHz, CDCl
1.99 (quint, J ¼ 5.3 Hz, 4H), 3.76 (t, J ¼ 5.5 Hz, 8H) 4.20 (s,12H) 5.02
s, 8H), 7.56 (d, J ¼ 8.0 Hz, 4H), 8.08 (d, J ¼ 8.0 Hz, 4H), 8.11 (s, 4H)
3
)
d
(
was added dropwise
a
THF (45 mL) solution of 1,8-
13
ppm; C NMR (100 MHz, CDCl
3
)
d
30.08, 60.94, 65.38, 71.15, 118.26,
bis(bromomethyl)-4,5-dimethoxypyrene (14, 0.448 g, 1.0 mmol)
over a 1 h period, and the resulting solution was stirred at reflux for
3 days. Ice water (30 mL) was slowly added. The solution was
1
2
2
22.73, 125.22, 127.79, 130.89, 144.04 ppm; IR (KBr) 1137, 1226,
ꢁ1
850, 2920 cm ; MS (FABþ) m/z (relative intensity, %) ¼ 226 (5),
þ
88 (42), 724 (60, M ); HRMS (FABþ) calcd for C46
H
44
O
8
: 724.3038,
extracted with CHCl
with CHCl
(30 mL ꢀ 3). The combined organic layers were washed
with saturated NaCl aqueous solution (30 mL), dried over Na SO
filtered, and concentrated in vacuo, giving a residue that was sub-
jected to silica gel column chromatography (
¼ 3 cm, l ¼ 15 cm,
eluent: CHCl ¼ 0.35) followed by recycling pre-
:EtOH ¼ 30:1, R
parative HPLC (GPC, eluent: CHCl to give 13,14,32,33-
tetramethoxy-2,5,8,21,24,27-hexaoxa[9.9](1,8)pyrenophane
3
(30 mL) and the aqueous layer was washed
found: 724.3024.
3
2
4
,
4.8. Preparation of pyrenophane 4
f
A mixture of 1,4-butanediol (0.099 g, 1.1 mmol) and NaH (60% in
mineral oil, 0.8 g, 20 mmol) in THF (120 mL) was stirred at reflux for
h under an argon atmosphere. To the solution was added drop-
wise THF (50 mL) solution of 1,8-bis(iodomethyl)-4,5-
3
f
3
)
1
(6,
H
ꢂ
1
a
0.020 g, 18% yield). Data for 6: orange solid; mp 191e193 C;
NMR (400 MHz, CDCl
8H), 7.86 (d, J ¼ 8.0 Hz, 4H), 8.29 (d, J ¼ 8.0 Hz, 4H), 8.45 (s, 4H)
dimethoxypyrene (15, 0.542 g, 1.0 mmol) over a 1 h period, and
the resulting solution was stirred at reflux for 3 days. Ice water
3
) d 3.69e3.76 (m, 16H), 4.15 (s, 12H), 5.16 (s,
13
(
(
30 mL) was slowly added. The solution was extracted with CHCl
30 mL) and the aqueous layer was washed with CHCl
(30 mL ꢀ 3).
3
ppm; C NMR (100 MHz, CDCl
3
) d 61.09, 69.44, 70.92, 71.95, 118.70,
3
123.19, 123.97, 127.32, 128.44, 129.24, 131.01, 144.36 ppm; IR (KBr)
ꢁ
1
The combined organic layers were washed with saturated NaCl
aqueous solution (30 mL), dried over Na SO filtered, and
concentrated in vacuo, giving a residue that was subjected to silica
gel column chromatography
¼ 3 cm, l ¼ 15 cm, eluent:
CH Cl ¼ 0.35e0.45) followed by recycling prepar-
:EtOH ¼ 30:1, R
ative HPLC (GPC, eluent: CHCl ) to give 12,13,30,31-tetramethoxy-
,7,20,25-tetraoxa[8.8](1,8)pyrenophane (4, 0.023 g, 6% yield). Data
829, 1137, 1504, 1612, 2862 cm ; MS (FABþ) m/z (relative intensity,
þ
2
4
,
%) ¼ 226 (1), 288 (23), 784 (10, M ); HRMS (FABþ) calcd for
48 49
C H O10: 785.3247, found: 785.3335.
(f
2
2
f
3
4.11. Preparation of pyrenophane 7
2
ꢂ
1
for 4: ocher solid; mp 169e171 C; H NMR (500 MHz, CDCl
3
)
A mixture of triethylene glycol (0.165 g, 1.1 mmol) and NaH (60%
in mineral oil, 0.8 g, 20 mmol) in THF (120 mL) was stirred at reflux
for 1 h under an argon atmosphere. To the solution was added
dropwise a THF (35 mL) solution of 1,8-bis(bromomethyl)-4,5-
dimethoxypyrene (14, 0.448 g, 1.0 mmol) over a 1 h period, and
the resulting solution was stirred at reflux for 3 days. Ice water
d
1.70e1.75 (m, 8H), 3.55e3.60 (m, 8H), 4.18 (s, 12H), 5.08 (s, 8H),
13
7
.95 (d, J ¼ 8.0 Hz, 4H), 8.40 (d, J ¼ 8.0 Hz, 4H), 8.50 (s, 4H) ppm;
C
3
NMR (100 MHz, CDCl ) d 22.64, 29.32, 61.11, 69.88, 71.66, 118.77,
1
23.31, 123.91, 127.30, 128.51, 129.27, 131.33, 144.38 ppm; IR (KBr)
ꢁ
1
1099, 1226, 2855, 2924 cm ; MS (FABþ) m/z (relative intensity,
þ
%
C
) ¼ 226 (2), 288 (28), 752 (12, M ); HRMS (FABþ) calcd for
(30 mL) was slowly added. The solution was extracted with CHCl
(30 mL) and the aqueous layer was washed with CHCl
(30 mL ꢀ 3).
The combined organic layers were washed with saturated NaCl
aqueous solution (30 mL), dried over Na SO filtered, and
concentrated in vacuo, giving a residue that was subjected to silica
gel column chromatography
¼ 3 cm, l ¼ 10 cm, eluent:
CH Cl ¼ 0.45e0.55) followed by recycling prepar-
:EtOH ¼ 15:1, R
ative HPLC (GPC, eluent: CHCl ) to give 16,17,38,39-tetramethoxy-
3
48
H
48
O
8
: 752.3349, found: 752.3335.
3
4.9. Preparation of pyrenophane 5
2
4
,
A mixture of 1,5-pentanediol (0.115 g,1.1 mmol) and NaH (60% in
(f
mineral oil, 0.8 g, 20 mmol) in THF (120 mL) was stirred at reflux for
h under an argon atmosphere. To the solution was added drop-
wise THF (30 mL) solution of 1,8-bis(bromomethyl)-4,5-
2
2
f
1
3
a
2,5,8,11,24,27,30,33-octaoxa[12.12](1,8)pyrenophane (7, 0.047 g,
12% yield) and 16,17-dimethoxy-2,5,8,11-tetraoxa[12](1,8)pyr-
enophane (16, 0.068 g, 16% yield). Data for 7: yellow solid; mp
dimethoxypyrene (14, 0.448 g, 1.0 mmol) over a 1 h period, and
the resulting solution was stirred at reflux for 3 days. Ice water
ꢂ
1
(
(
30 mL) was slowly added. The solution was extracted with CHCl
30 mL) and the aqueous layer was washed with CHCl
(30 mL ꢀ 3).
3
157e160 C; H NMR (500 MHz, CDCl
3
) d 3.62e3.68 (m, 24H), 4.16
3
(s, 12H), 5.16 (s, 8H), 7.93 (d, J ¼ 8.0 Hz, 4H), 8.36 (d, J ¼ 8.0 Hz, 4H),
13
The combined organic layers were washed with saturated NaCl
aqueous solution (30 mL), dried over Na SO filtered, and
concentrated in vacuo, giving a residue that was subjected to silica
gel column chromatography
¼ 3 cm, l ¼ 10 cm, eluent:
CH Cl ¼ 0.35e0.45) followed by recycling prepar-
:EtOH ¼ 30:1, R
ative HPLC (GPC, eluent: CHCl ) to give 13,14,32,33-tetramethoxy-
,8,21,27-tetraoxa[9.9](1,8)pyrenophane (5, 0.035 g, 10% yield).
8.41 (s, 4H) ppm; C NMR (100 MHz, CDCl
3
) d 61.09, 69.56, 70.69,
2
4
,
70.73, 71.98, 118.79, 123.17, 123.94, 127.52, 128.51, 129.28, 130.97,
ꢁ
1
144.37 ppm; IR (KBr) 1134, 1226, 2858 cm ; MS (FABþ) m/z
þ
(f
(relative intensity, %) ¼ 226 (2), 288 (8), 872 (6, M ). HRMS (FABþ)
2
2
f
56
calcd for C52H O12: 872.3772, found: 872.3777. Data for 16: ocher
ꢂ
1
3
solid; mp 143e145 C; H NMR (400 MHz, CDCl
3
) d 3.50 (s, 4H),
2
3.58e3.61 (m, 8H), 4.20 (s, 6H), 5.29 (s, 4H), 7.91 (d, J ¼ 7.6 Hz, 2H),
ꢂ
1
13
Data for 5: ocher solid; mp 166e167 C; H NMR (500 MHz, CDCl
3
)
8.38 (d, J ¼ 8.0 Hz, 2H), 8.67 (s, 2H) ppm; C NMR (100 MHz, CDCl
61.15, 69.34, 70.57, 71.02, 72.94, 118.32, 123.23, 125.05, 127.47,
128.84, 129.76, 131.33, 144.53 ppm; IR (KBr) 1099, 1227, 2878,
3
)
d
1.52e1.66 (m, 12H), 3.46e3.52 (m, 8H), 4.16 (s, 12H), 5.07 (s, 8H),
d
13
7
.93 (d, J ¼ 8.0 Hz, 4H), 8.36 (d, J ¼ 8.0 Hz, 4H) 8.40 (s, 4H) ppm;
C
ꢁ
1
NMR (100 MHz, CDCl
3
)
d
22.64, 29.32, 61.11, 69.88, 71.66, 118.77,
2947 cm ; MS (FABþ) m/z (relative intensity, %) ¼ 226 (1), 288
þ
1
23.31, 123.91, 127.30, 128.51, 129.27, 131.33, 144.38 ppm; IR (KBr)
(49), 436 (100, M ). HRMS (FABþ) calcd for C26
28 6
H O : 436.1886,
ꢁ1
1191, 1227, 2858, 2932 cm ; MS (EI) m/z (relative intensity,
found: 436.1893.
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512

H. Maeda et al. / Tetrahedron xxx (xxxx) xxx
9
Acknowledgments
3929e3939.
[
[
[
[
26] T. Kawashima, T. Otsubo, Y. Sakata, S. Misumi, Tetrahedron Lett. 19 (1978)
115e5118.
5
This study was financially supported by a Grant-in-Aid for Sci-
entific Research (C) (20550049, 23550047, 26410040, 17K05777)
from the Ministry of Education, Culture, Sports, Science and Tech-
nology (MEXT) of Japan. H. M. is also grateful for financial support
from The Mazda Foundation, The Murata Science Foundation, Izumi
Science and Technology Foundation, Shibuya Science Culture and
Sports Foundation, A-STEP (Adaptable and Seamless Technology
Transfer Program through target-driven R&D, JST, Japan), and
Kanazawa University SAKIGAKE Project. We thank Professor
Tsuyoshi Asakawa, Associate Professor Akio Ohta, Professor Tadaaki
Yamagishi, and Professor Tomoki Ogoshi at Kanazawa University
for permission to use UVevis absorption and fluorescence spec-
trophotometers. We thank Professor Seiichi Nishizawa at Tohoku
University for permission to use fluorescence lifetime measure-
ment system. We are also indebted to Professor Shigehisa Akine at
Kanazawa University for donation of the TitrationFit 2014-0630
program.
27] M. Inouye, K. Fujimoto, M. Furusyo, H. Nakazumi, J. Am. Chem. Soc. 121 (1999)
1452e1458.
28] H. Abe, Y. Mawatari, H. Teraoka, K. Fujimoto, M. Inouye, J. Org. Chem. 69
(2004) 495e504.
29] H. Hayashi, N. Matsumura, K. Mizuno, J. Chem. Res. (2004) 599e601.
[30] K. Imai, S. Hatano, A. Kimoto, J. Abe, Y. Tamai, N. Nemoto, Tertahedron 66
2010) 8012e8017.
(
[
[
31] Y. Sagara, N. Tamaoki, RSC Adv. 7 (2017) 47056e47062.
32] T. Umemoto, T. Kawashima, Y. Sakata, S. Misumi, Chem. Lett. 4 (1975)
837e840.
[
[
[
[
33] T. Hayashi, N. Mataga, Y. Sakata, S. Misumi, Chem. Phys. Lett. 41 (1976)
325e328.
34] T. Hayashi, N. Mataga, T. Umemoto, Y. Sakata, S. Misumi, J. Phys. Chem. 81
(1977) 424e429.
35] T. Yamato, A. Miyazawa, M. Tashiro, J. Chem. Soc. Perkin Trans. 1 (1993)
3127e3137.
36] H. Maeda, M. Hironishi, R. Ishibashi, K. Mizuno, M. Segi, Photochem. Photobiol.
Sci. 16 (2017) 228e237.
[37] H. Maeda, K. Nakamura, T. Furuyama, M. Segi, Photochem. Photobiol. Sci.
2019), https://doi.org/10.1039/C9PP00239A in press.
(
[
[
38] J. Hu, D. Zhang, F.W. Harris, J. Org. Chem. 70 (2005) 707e708.
39] J.C. Walsh, K.-L.M. Williams, D. Lungerich, G.J. Bodwell, Eur. J. Org. Chem.
(2016) 5933e5936.
[
[
40] G. Venkataramana, P. Dongare, L.N. Dawe, D.W. Thompson, Y. Zhao,
G.J. Bodwell, Org. Lett. 13 (2011) 2240e2243.
41] A.M. Dmytrejchuk, S.N. Jackson, R. Meudom, J.D. Gorden, B.L. Merner, J. Org.
Chem. 83 (2018) 10660e10667.
Appendix A. Supplementary data
Supplementary data to this article can be found online at
https://doi.org/10.1016/j.tet.2019.130512.
[42] H. Maeda, K. Hirose, M. Segi, J. Lumin. 204 (2018) 269e277.
[43] I. Yamaguchi, K. Sato, Bull. Chem. Soc. Jpn. 86 (2013) 1174e1182.
[44] F. Lu, N. Kitamura, T. Takaya, K. Iwata, T. Nakanishi, Y. Kurashige, Phys. Chem.
Chem. Phys. 20 (2018) 3258e3264.
References
[
[
45] C. Reichardt, Chem. Rev. 94 (1994) 2319e2358.
46] N. Sadhukhan, T. Muraoka, D. Abe, Y. Sasanuma, D.R.G. Subekti, K. Kinbara,
Chem. Lett. 43 (2014) 1055e1057.
[
[
[
[
1] J.B. Birks, Acta Phys. Pol. 34 (1968) 603e617.
2] Th. F o€ rster, Angew. Chem. Int. Ed. 8 (1969) 333e343.
[
[
[
47] S. Kawasaki, T. Muraoka, H. Obara, T. Ishii, T. Hamada, K. Kinbara, Chem. Asian
J. 9 (2014) 2778e2788.
48] K.E. Krakowiak, J.S. Bradshaw, D.J. Zamecka-Krakowiak, Chem. Rev. 89 (1989)
3] K. Zachariasse, W. Kühnle, Z. Phys. Chem. 101 (1976) S267eS276.
4] F.C. De Schryver, P. Collart, J. Vandendriessche, R. Goedeweeck, A.M. Swinnen,
M. Van der Auweraer, Acc. Chem. Res. 20 (1987) 159e166.
929e972.
[
[
[
[
[
5] F.M. Winnik, Chem. Rev. 93 (1993) 587e614.
49] G.W. Gokel (Ed.), Crown Ethers & Cryptands, Royal Society of Chemistry,
London, 1991.
6] S. Karuppannan, J.-C. Chambron, Chem. Asian J. 6 (2011) 964e984.
7] M.E. Østergaard, P.J. Hrdlicka, Chem. Soc. Rev. 40 (2011) 5771e5788.
8] T.M. Figueira-Duarte, K. Müllen, Chem. Rev. 111 (2011) 7260e7314.
9] G. Bains, A.B. Patel, V. Narayanaswami, Molecules 16 (2011) 7909e7935.
[
[
50] R. Cacciapaglia, L. Mandolini, Chem. Soc. Rev. 22 (1993) 221e231.
51] A.P. de Silva, D.B. Fox, A.J.M. Huxley, T.S. Moody, Coord. Chem. Rev. 205 (2000)
41e57.
[
[
[
[
10] E. Manandhar, K.J. Wallace, Inorg. Chim. Acta 381 (2012) 15e43.
11] J. Duhamel, Langmuir 28 (2012) 6527e6538.
12] J.J. Bryant, U.H.F. Bunz, Chem. Asian J. 8 (2013) 1354e1367.
13] J.M. Casas-Solvas, J.D. Howgego, A.P. Davis, Org. Biomol. Chem. 12 (2014)
[52] S. Fery-Forgues, F. Al-Ali, J. Photochem. Photobiol. C 5 (2004) 139e153.
[53] G.W. Gokel, W.M. Leevy, M.E. Weber, Chem. Rev. 104 (2004) 2723e2750.
[54] J. Li, D. Yim, W.-D. Jang, J. Yoon, Chem. Soc. Rev. 46 (2017) 2437e2458.
[55] J.S. Renny, L.L. Tomasevich, E.H. Tallmadge, D.B. Collum, Angew. Chem. Int. Ed.
212e232.
5
2 (2013) 11998e12013.
56] F. Ulatowski, K. Dabrowa, T. Balakier, J. Jurczak, J. Org. Chem. 81 (2016)
746e1756.
[14] X. Feng, J.-Y. Hu, C. Redshaw, T. Yamato, Chem. Eur. J. 22 (2016) 11898e11916.
[15] P.G. Ghasemabadi, T. Yao, G. Bodwell, J. Chem. Soc. Rev. 44 (2015) 6494e6518.
[16] T. Umemoto, S. Satani, Y. Sakata, S. Misumi, Tetrahedron Lett. 16 (1975)
[
1
[
[
[
57] D.B. Hibbert, P. Thordarson, Chem. Commun. 52 (2016) 12792e12805.
58] P. Thordarson, Chem. Soc. Rev. 40 (2011) 1305e1323.
3
159e3162.
17] R.H. Mitchell, R.J. Carruthers, J.C.M. Zwinkels, Tetrahedron Lett. 17 (1976)
585e2588.
18] H. Irngartinger, R.G.H. Kirrstetter, C. Krieger, H. Rodewald, H.A. Staab, Tetra-
hedron Lett. 18 (1977) 1425e1428.
[
[
[
59] L. Pauling (Ed.), The Nature of the Chemical Bond, third ed., Cornell Univeristy
Press, Ithaca, NY, 1960.
60] A.L. Macanita, K.A. Zachariasse, J. Phys. Chem. A 115 (2011) 3183e3195.
61] A. Siemiarczuk, W.R. Ware, J. Phys. Chem. 93 (1989) 7609e7618.
62] K.A. Zachariasse, W. Kühnle, U. Leinhos, P. Reynders, G. Striker, J. Phys. Chem.
2
[
[
[
19] K. Ishizu, Y. Sugimoto, T. Umemoto, Y. Sakata, S. Misumi, Bull. Chem. Soc. Jpn.
50 (1977) 2801e2802.
9
5 (1991) 5476e5488.
63] M.J. Snare, P.J. Thistlethwaite, K.P. Ghiggino, J. Am. Chem. Soc. 105 (1983)
328e3332.
[20] Y. Kai, F. Hama, N. Yasuoka, N. Kasai, Acta Crystallogr. B34 (1978) 1263e1270.
[21] H.A. Staab, R.G.H. Kirrstetter, Liebigs Ann. Chem. (1979) 886e898.
[22] S. Ishikawa, J. Nakamura, S. Iwata, M. Sumitani, S. Nagakura, Y. Sakata,
S. Misumi, Bull. Chem. Soc. Jpn. 52 (1979) 1346e1350.
[
[
[
[
3
64] D. Declercq, P. Delbeke, F.C. De Schryver, L. Van Meervelt, R.D. Miller, J. Am.
Chem. Soc. 115 (1993) 5702e5708.
[
[
[
23] A. Terahara, H. Ohya-Nishiguchi, N. Hirota, Y. Sakata, S. Misumi, K. Ishizu, Bull.
Chem. Soc. Jpn. 55 (1982) 3896e3898.
24] H.A. Staab, N. Riegler, F. Diederich, C. Krieger, D. Schweitzer, Chem. Ber. 117
65] M. Kida, M. Kubo, T. Ujihira, T. Ebata, M. Abe, Y. Inokuchi, ChemPhysChem 19
(
2018) 1331e1335.
66] G.A. Olah, S.C. Narang, B.G.B. Gupta, R. Malhotra, J. Org. Chem. 44 (1979)
247e1251.
(
1984) 246e259.
1
25] P. Reynders, W. Kühnle, K.A. Zachariasse, J. Am. Chem. Soc. 112 (1990)
Please cite this article as: H. Maeda et al., Synthesis, fluorescence properties, and conformational analysis of ether-linked (1,8)pyrenophanes,
Tetrahedron, https://doi.org/10.1016/j.tet.2019.130512