Synthesis, structures and inclusion properties of tetranaphthalides: New macrocyclic clathrate hosts

Article abstract of DOI:10.1016/j.tet.2011.02.053

Novel tetranaphthalide host compounds 3 and 4 bearing isomeric naphthalene moieties have been synthesized and their inclusion properties were investigated. These host compounds enclathrated several kinds of ketones, cyclic ethers, amides, sulfoxides and aromatic compounds. The structures of two representative inclusion compounds containing different host molecules and a common guest (dimethyl sulfoxide) were investigated by X-ray diffraction to determine the nature of guest inclusion and to rationalize their distinctly different thermal decomposition profiles.

Full text of DOI:10.1016/j.tet.2011.02.053

Tetrahedron 67 (2011) 2911e2915
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Synthesis, structures and inclusion properties of tetranaphthalides: new
macrocyclic clathrate hosts
,
a
a
a
b,
Koichi Tanaka a , Kyosuke Hori , Asuka Masumoto , Ryuichi Arakawa , Mino R. Caira
*
*
a Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University, Suita, Osaka 564-8680, Japan
b Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
a r t i c l e i n f o
a b s t r a c t
Article history:
Novel tetranaphthalide host compounds 3 and 4 bearing isomeric naphthalene moieties have been
synthesized and their inclusion properties were investigated. These host compounds enclathrated sev-
eral kinds of ketones, cyclic ethers, amides, sulfoxides and aromatic compounds. The structures of two
representative inclusion compounds containing different host molecules and a common guest (dimethyl
sulfoxide) were investigated by X-ray diffraction to determine the nature of guest inclusion and to ra-
tionalize their distinctly different thermal decomposition profiles.
Received 5 December 2010
Received in revised form 18 February 2011
Accepted 21 February 2011
Available online 26 February 2011
Ó 2011 Elsevier Ltd. All rights reserved.
1. Introduction
2. Results and discussion
There has been increasing interest in host/guest inclusion
compounds because of their potential applications, such as sepa-
ration of isomeric compounds,1 optical resolution of racemates,2
reaction medium of included molecules3 and sensor materials.4
Macrocyclic host compounds have been studied intensively dur-
ing the last few decades.5 Calixarene is one of the useful host
molecules in supramolecular systems and the subtype of hetero-
atom-bridged calixarene compounds including oxygen,6 sulfur,7
nitrogen8 and amide9 has been developed. Recently, we reported
the synthesis, crystal structure and inclusion properties of novel
ester bond bridged calixarene analogues, tetra- and hexa-salicylide
hosts (1 and 2).10 The tetrasalicylide hosts having a 5-substituted
halogen atom on the aromatic ring form organogels with several
kinds of organic solvents, whereas the hexa-salicylide hosts are
prone to include several organic solvent molecules in the solid
state. With a view to exploring the potential host properties of
isologues of tetra- and hexa-salicylides, we have examined the
cyclocondensation reaction of some hydroxynaphthoic acid de-
rivatives as valuable precursors bearing larger aromatic compo-
nents. Here, we report the synthesis and inclusion properties of
novel tetranaphthalide host compounds 3a,b and 4, as well as two
representative crystal structures.
2.1. Synthesis of tetranaphthalides and their inclusion
properties
The tetranaphthalides were synthesized by a cyclization re-
action of the corresponding hydroxynaphthoic acid derivatives in
toluene in the presence of POCl3. For example, a mixture of 3-hy-
droxy-2-naphthoic acid 5a and POCl3 was heated in toluene under
reflux for 6 h. After cooling the reaction mixture to room temper-
ature, the crystals deposited were separated by filtration and
washed with water and aq NaHCO3 solution and filtered. The
crystalline solid was collected and purified by silica gel column
chromatography to give 3a in 54% yield.
Similar treatment of 7-methoxy-3-hydroxy-2-naphthoic acid 5b
and 1-hydroxy-2-naphthoic acid 6 afforded corresponding tetra-
naphthalides 3b and 4 in 48% and 23% yield, respectively. However,
similar treatment of 2-hydroxy-1-naphthoic acid 7 gave only 2-
naphthol 8 in 54% yield instead of the tetranaphthalide. This may be
due to the severe steric repulsion between aromatic rings of the
naphthalide.
A variety of organic solvents including cyclic ethers, cyclic and
acyclic ketones, amides, sulfoxides and several kinds of aromatic
compounds were used for the inclusion experiments (Table 1). The
inclusion crystals were obtained by recrystallization of the tetra-
naphthalide from the respective guest solvents. The host/guest
ratios were evaluated by TGA and 1H NMR spectral integration. As
shown in Table 1, tetranaphthalides 3a and 3b showed excellent
inclusion ability and included all the guest solvents tested in
Table 1. The host/guest stoichiometric ratios of 1:5 (guests: cyclo-
hexanone, DMSO) and 1:4 (guests: diethylketone, aniline) are
* Corresponding authors. E-mail address: ktanaka@ipcku.kansai-u.ac.jp (K.
Tanaka).
0040-4020/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2011.02.053

2912
K. Tanaka et al. / Tetrahedron 67 (2011) 2911e2915
X
exceptionally large, which indicates the high efficiency of guest
X
X
accommodation by these host compounds. However, tetranaph-
thalide 4 showed relatively poor inclusion ability. This is attribut-
able to the low symmetry of the molecular structure of 4. As for the
inclusion of DMSO, host 3b showed higher guest release temper-
ature (237 ꢀC) than that of host 3a and 4. The thermogravimetric
analysis (TGA) data for these complexes are shown in Fig. 1. Similar
behaviour was observed for the inclusion of 3-methylpyridine.
O
O
X
O
C
O
O
O
O
O
O
O
C
C
O
O
O
X
O
X
O
C
O
O
O
O
X
O
X
a: X = H d: X = Br
b: X = F e: X = I
c: X = Cl
1
X
Y
X
2
Y
Y
Y
O
C
O
C
O
C
O
O
Y
CO2H
OH
O
Δ
O
C
C
O
O
O
C
C O
O
O
C
C
O
O
O
O
POCl3 / toluene
O
a: Y = H
O
C
O
O
C
O
O
C
O
b: Y = OMe
5
a: Y = H
b: Y = OMe
3
Y
4
3
Y
Y
Y
O
C
Table 1
O
Host/guest ratios and guest release temperatures of the inclusion crystals of 3a, 3b
and 4
Δ
O
C
C
O
O
CO2H
O
Guest
3a
3b
4
da
POCl3 / toluene
OH
Diethylketone
Cyclopentanone
Cyclohexanone
1,4-Dioxane
DMSO
DMF
Pyridine
2-Methylpyridine
3-Methylpyridine
4-Methylpyridine
Benzene
1:4b (84)c
2:3 (161)
1:5 (102)
2:3 (145)
1:5 (120)
1:2 (176)
1:2 (65)
1:3 (122)
1:3 (146)
1:1 (173)
1:2 (83)
1:4 (169)
1:3 (127)
1:2 (137)
1:3 (123, 162)
1:3 (126)
1:1 (185)
1:3 (128)
1:1 (184)
1:2 (113, 152)
2:3 (84)
1:1 (57)
2:3 (76)
1:1 (70)
O
C
O
6
1:1 (165)
1:2 (137, 175)
2:3 (94, 138)
1:2 (121)
d
4
1:2 (237)
1:2 (191, 212)
1:1 (64)
2:3 (124, 143)
1:2 (185)
1:2 (120, 146)
1:1 (70)
1:2 (118)
1:2 (69)
1:1 (70)
1:1 (72)
1:1 (68, 172)
1:1 (78)
2:1 (75)
1:1 (60)
1:4 (89)
1:1 (136)
1:1 (101)
1:1 (163)
1:1 (72)
1:3 (103, 151)
d
Δ
OH
CO2H
OH
POCl3 / toluene
8
Aniline
Anisole
7
Chlorobenzene
Bromobenzene
o-Dichlorobenzene
m-Dichlorobenzene
o-Xylene
d
d
1:2 (137, 147)
1:1 (139)
1:1 (176)
1:1 (157)
2:3 (106, 139)
2.2. X-ray structural analyses
m-Xylene
p-Xylene
Table 2 lists crystal data and refinement parameters for the
representative inclusion compounds 3a$(DMSO)5 and 3b$(DMSO)2,
whose structures were investigated to establish the nature of
common guest inclusion by the respective host molecules and to
rationalize the significantly different thermal stabilities of these
species (Fig. 1).
1:1 (72)
a
No inclusion complexation.
b
c
Host/guest ratios were determined by TG and 1H NMR spectroscopy.
Guest release temperature (ꢀC).
Table 2
Crystal data and refinement parameters for two representative inclusion com-
pounds of host molecules 3a and 3b
3a$(DMSO)5
3b$(DMSO)2
C48H32 12$ (C2H6OS)2
956.99
Formula
C44H24O8$(C2H6OS)5
1071.27
O
Formula weight
Crystal system
Space group
Tetragonal
I41/a
18.9747 (4)
14.6378 (4)
5270.2 (2)
4
Tetragonal
I41/a
13.9412 (19)
23.0660 (16)
4483.0 (9)
4
ꢀ
a, A
ꢀ
c, A
V, A
3
ꢀ
Z
T, K
113 (2)
0.71073 (Mo K
0.0486
100 (2)
0.71073 (Mo K
0.0437
ꢀ
l, A
a
)
a)
R1
wR2
Goodness of fit
0.1151
1.055
0.1143
1.038
Fig. 1. TGA traces for the 1:5 DMSO complex of 3a (blue line) and 1:2 DMSO complex
of 3b (red line).

K. Tanaka et al. / Tetrahedron 67 (2011) 2911e2915
2913
In effect, the host surface is almost completely solvated by
surrounding DMSO molecules. As a result, there are no direct
host/host interactions. Instead, DMSO molecules act as bridges
between neighbouring host molecules (Fig. 4). Thus, each naph-
thalene ring of host molecule 3a engages in two CeH/O hydrogen
bonds, the acceptors being oxygen atoms of inversion-related
DMSO molecules. The result is a centrosymmetric ring motif, R (14),
ꢀ
ꢀ
with C/O distances 3.356 (3) A (C1eH1/O15) and 3.299 (3) A
(C7eH7/O15). There are no significant -interactions between
p
aromatic rings of neighbouring host molecules.
Fig. 2. ORTEP diagram of host 3a in its inclusion compound with DMSO, showing the
atomic numbering of the asymmetric unit and thermal ellipsoids drawn at the 50%
probability level.
Fig. 4. Hydrogen bonded motif in 3a$(DMSO)5.
The molecule of tetranaphthalide 3a (Fig. 2) is located on
a fourfold inversion centre with the orientations of the four
naphthalene residues alternating up and down, these residues
being held together by trans ester linkages (representative torsion
angle C3eC11eO13eC2i¼ꢁ174.2 (2)ꢀ, i¼3/4ꢁy, ꢁ1/4þx, 3/4ꢁz).
Furthermore, the conformation adopted by 3a is that in which the
four carbonyl groups are directed away from the inversion centre,
ester oxygen atom O13 and its three symmetry-related counter-
parts forming a flattened tetrahedron at the centre of the molecule
with O/Cg/O angles in the range 96.8e139.7ꢀ (where Cg is the
centroid of the four ester O atoms). The closest O/O contact dis-
The distinctive two-step TGA mass loss observed on heating
inclusion compound 3a$(DMSO)5 can be accounted for qualitatively
and quantitatively on the basis of its crystal structure. As noted
above, the included DMSO molecules occur in two distinct sets in
a ratio of 4:1, those in general positions (16 per unit cell) and those
arranged around the positions of fourfold-inversion symmety (4
per unit cell). Fig. 5 shows the arrangement of the DMSO molecules
located in general positions. They generate a series of infinite spi-
rals parallel to the crystal c-axis. Within a spiral, the DMSO mole-
cules are in close contact.
ꢀ
tance is 2.645 (1) A. As concerns inclusion ability, an important
parameter characterizing host molecule 3a is the angle between
two diad-related naphthalene rings, since this determines the size
of guest or guest residue that may be accommodated within the V-
shaped groove, which these planes define. For the conformation
adopted by molecule 3a, this angle is 54.8 (1)ꢀ.
In the asymmetric unit of 3a$(DMSO)5, there are two crystal-
lographically independent DMSO molecules: one of these is located
in a general position (multiplicity 16) while the other is disordered
around a position of fourfold-inversion (-4) symmetry, with the
oxygen atom on the C2-axis passing through this point (accounting
for four additional DMSO molecules per unit cell). The host/guest
ratio is thus 4:20, or 1:5 (Table 1). The DMSO content is high owing
to accommodation of solvent molecules both within the hosts’
V-shaped clefts (disordered DMSO) and in the interstitial spaces
between host molecules (ordered DMSO). Fig. 3 shows a single
molecule of 3a with its assembly of nearest-neighbour DMSO
molecules.
Fig. 5. Stereoview of the arrangement of DMSO molecules located in general positions
in the unit cell. For clarity, a representative spiral is shown in green.
In contrast, DMSO molecules located around fourfold inversion
axes are very efficiently encapsulated within the cavity formed by
two abutting host molecules. In Fig. 6, one such representative
Fig. 3. Stereoview of a single molecule of host 3a surrounded by DMSO molecules. The
host molecule is represented in stick mode while the solvent molecules are shown in
ball-and-stick representation.
Fig. 6. Stereoview of a disordered DMSO molecule in 3a$(DMSO)5 enclathrated by two
host molecules.

2914
K. Tanaka et al. / Tetrahedron 67 (2011) 2911e2915
disordered molecule of DMSO (of four in the unit cell) is shown for
simplicity.
Neighbouring host molecules 3b are tethered by bifurcated
hydrogen bonds C5eH/O14iii (iii¼3/4ꢁy, 1/4þx, 1/4þz) and
C5eH/O15iv (iv¼ꢁ1/2þx, y, 1/2ꢁz) with C/O distances of 3.397
Thus, on heating the inclusion compound 3a$(DMSO)5, it can be
envisaged that the weakly bound DMSO molecules, arranged in
continuous infinite spirals (Fig. 5), diffuse along the z-direction out
of the crystal first (i.e., at relatively low temperature, w120 ꢀC), as
shown in Fig. 1, accounting for an initial observed mass loss of
w30% (calcd for loss of four DMSO molecules per 3a$(DMSO)5 unit:
29.2%). This would be followed by the loss of the significantly more
tightly bound DMSO molecules (Fig. 6) at considerably higher
temperature (w170 ꢀC), accounting for the observed second mass
loss of w5% (Fig. 1). The theoretical mass loss for the remaining
DMSO molecule in 3a$(DMSO)5 is 7.3%.
ꢀ
(2) and 3.184 (2) A, respectively.
The DMSO molecule in the inclusion compound 3b$(DMSO)2 is
disordered around the crystallographic twofold rotation axis,
which intersects the host symmetry centre. Host and guest mole-
cules in the unit cell thus have respective site multiplicities of 4 and
8, accounting for the stated 1:2 stoichiometry (Table 1). Only the
oxygen atom of the solvent molecule is located on the C2-axis and
the geometry at the sulfur atom is slightly pyramidal, as usually
observed.
As for the inclusion compound 3a$(DMSO)5, the TGA profile for
3b$(DMSO)2 is readily explained on the basis of its crystal structure.
In contrast to the former compound, there is a one-step mass loss in
TGA for 3b$(DMSO)2, which is consistent with the DMSO molecules
occupying only one type of crystallographic site. It is evident from
the partial packing diagram shown in Fig. 9 that each solvent
molecule is accommodated within the V-shaped cleft of a host
molecule and is further entrapped by methoxynaphthalene rings of
neighbouring host molecules. Fig. 9 shows the complete encapsu-
lation of two DMSO molecules that are related by the fourfold in-
version centre situated at 1/2, 3/4, 5/8. As revealed by comparative
space-filling diagrams, this DMSO inclusion mode is even more
severely constricting than that shown in Fig. 6 and thus accounts
for the exceptionally high onset temperature of desolvation
(237 ꢀC) when crystals of 3b$(DMSO)2 are heated (Table 1).
The inclusion compound 3b$(DMSO)2 also crystallizes in the
tetragonal space group I41/a with the host molecule again located
on a fourfold inversion centre (Fig. 7). However, relative to host 3a,
molecule 3b adopts an inverted conformation, with the four car-
bonyl groups (C13]O14 and symmetry-related counterparts) now
directed towards the centre of the host molecule while the four
ester oxygen atoms (O15 and counterparts) are at the periphery.
The four carbonyl oxygen atoms are in a slightly distorted tet-
rahedral array (O/Cg/O angles in the range 102.9e112.9ꢀ, where
ꢀ
Cg is the centroid) and the shortest O/O contact is 2.996 (1) A.
trans Ester linkages (C1eC13eO15eC2ii¼ꢁ170.1 (1)ꢀ, ii¼5/4ꢁy,
1/4þx, 1/4ꢁz) are again responsible for holding the macrocycle
together. A further consequence of the inverted conformation in 3b
is that the angle between diad-related naphthalene ring planes is
85.6 (1)ꢀ, i.e., considerably larger than that in 3a, namely 54.8 (1)ꢀ.
The distinctly different conformations of host molecules 3a and 3b
are further contrasted in Fig. 8.
Fig. 9. Stereoview showing isolated DMSO molecules encapsulated by the host matrix
in the inclusion compound 3b$(DMSO)2.
In summary, in addition to the synthesis of the novel hosts de-
scribed in this paper and investigation of their inclusion properties,
X-ray analyses of representative inclusion compounds of host
molecules 3a and 3b with the common solvent DMSO revealed
significant differences in host conformations as well as significantly
different modes of guest inclusion. Furthermore, the X-ray struc-
tural data enabled the authors to rationalize the distinctly different
thermal desolvation profiles of 3a$(DMSO)5 and 3b$(DMSO)2.
Fig. 7. ORTEP diagram of host 3b in its inclusion compound with DMSO, showing
atomic numbering of the asymmetric unit and thermal ellipsoids drawn at the 50%
probability level.
3. Experimental
3.1. General
1H NMR spectra were recorded in CDCl3 on a JEOL JNM-GSX 400
FT-NMR spectrometer. IR spectra were recorded with a JASCO FT-IR
4100 spectrometer. Thermogravimetric analyses (TG) were per-
formed on a Rigaku TG-8120 instrument. X-ray analyses are de-
scribed in Section 3.3. ESI mass spectra were obtained by a triple
quadrupole mass spectrometer TSQ (ThermoFisher) in a positive
ion mode. The capillary temperature was 250 ꢀC, spray voltage
4.5 kV, auxiliary gas pressure 20 psi and sheath gas pressure 60 psi.
Fig. 8. Host molecules 3a (left) and 3b (right) viewed down their symmetry axes.

K. Tanaka et al. / Tetrahedron 67 (2011) 2911e2915
2915
3.2. Synthesis of host compounds
Absorption corrections were applied to both data sets.13 Struc-
tures were solved by direct methods and refined by full-matrix
least-squares methods using programs in the SHELX suite.14 All
non-H atoms were refined anisotropically. Hydrogen atoms were
located in difference electron density maps and were included in
a riding model with isotropic displacement parameters fixed at
1.2e1.5 those of their parent atoms.
3.2.1. Synthesis of tetranaphthalide 3a. A mixture of 3-hydroxy-2-
naphthoic acid 5 (2.8 g, 15 mmol), POCl3 (3 mL, 30 mmol) and tol-
uene (30 mL) was heated under reflux for 6 h. After cooling the
reaction mixture to room temperature, water was added. The
crystals deposited were separated by filtration and washed with
water and aq NaHCO3 solution. The crystalline solid was purified by
silica gel column chromatography using AcOEt as eluent to give 3a
as white solid. Yield 54% (1.5 g); mp>300 ꢀC; IR (Nujol) 1745 cmꢁ1
Acknowledgements
(C]O); 1H NMR (CDCl3, 400 MHz)
d 8.98 (s, 4H, Ar), 7.93 (d,
This work was supported by ‘High-Tech Research Center’ Project
for Private Universities: mating fund subsidy from MEXT (Ministry
of Education, Culture, Sports, Science and Technology), 2005e2009.
M.R.C. thanks the University of Cape Town and the NRF (Pretoria)
for research support.
J¼8.0 Hz, 4H, Ar), 7.76 (d, J¼8.0 Hz, 4H, Ar), 7.66 (s, 4H, Ar), 7.55 (t,
J¼6.8 Hz, 4H, Ar), 7.48 (t, J¼6.8 Hz, 4H, Ar); 13C NMR (CDCl3,
67.8 MHz)
d 163.5, 147.1, 136.1, 135.2, 130.8, 129.25, 129.29, 127.2,
126.7, 121.7, 120.8. Anal. Calcd for C44H24O8: C 77.64, H 3.55; found:
C 77.35, H 3.71; MS (ESI) m/z: 687.29 [MþLi]; 719.29 [MþK].
Supplementary data
3.2.2. Synthesis of tetranaphthalide 3b. A mixture of 3-hydroxy-2-
naphthoic acid 5 (3.3 g, 15 mmol), POCl3 (3 mL, 30 mmol) and tol-
uene (40 mL) was heated under reflux for 6 h. After cooling the
reaction mixture to room temperature, water was added. The
crystals deposited were separated by filtration and washed with
water and aq NaHCO3 solution. The crystalline solid was purified by
silica gel column chromatography using AcOEt as eluent to give 3b
as pale yellow solid. Yield 48% (1.5 g); mp>300 ꢀC; IR (Nujol)
CCDC 809198 and 802802 contain the supplementary crystal-
lographic data for this paper. These data can be obtained free of
charge at ‘http://www.ccdc.cam.ac.uk/conts/retrieving.html’ [or
from the Cambridge Crystallographic Data Centre, 12, Union Road,
Cambridge CB2 1EZ, UK; e-mail: deposit@ccdc.cam.sc.uk].
References and notes
1742 cmꢁ1 (C]O); 1H NMR (CDCl3, 400 MHz)
4H, Ar), 7.98e7.73 (m, 12H, Ar), 7.60e7.51 (m, 8H, Ar); 13C NMR
(CDCl3, 67.8 MHz) 162.9, 157.9, 144.6, 132.7, 131.7, 130.9, 128.7,
d
8.12 (d, J¼8.8 Hz,
1. Inclusion Compounds; Atwood, J. L., Davies, J. E. D., MacNicol, D. D., Eds.; Aca-
demic: Oxford, 1994; Vols. 1e3; Comprehensive Supramolecular Chemistry; At-
wood, J. L., Davies, J. E. D., MacNicol, D. D., Eds.; Pergamon: Oxford, 1996; Vols.
1e11; Separations and Reactions in Organic Supramolecular Chemistry; Toda, F.,
Bishop, R., Eds.; Wiley: Chichester, 2004; Tanaka, K.; Nakashima, A.; Shimada,
Y.; Scott, J. L. Eur. J. Org. Chem. 2006, 2423e2428; Yun Hang, H.; Eli, R. Angew.
Chem., Int. Ed. 2006, 45, 2011e2013; Scott, J. L.; Hachiken, S.; Tanaka, K. Cryst.
Growth Des. 2008, 8, 2447e2452.
d
122.3, 121.4, 121.0, 107.3, 55.4. Anal. Calcd for C48H32O12: C 72.00, H
4.03; found: C 71.72, H 4.09; MS (ESI) m/z: 807.32 [MþLi]; 839.41
[MþK].
2. For example Tanaka, K.; Takenaka, H.; Caira, M. R. Tetrahedron: Asymmetry
2006, 17, 2216e2219; Miyata, M.; Tohnai, N.; Hisaki, I. Acc. Chem. Res. 2007, 40,
649e702; Urbanczyk-Lipkowska, Z.; Fukuda, N.; Tanaka, K. Tetrahedron:
Asymmetry 2007, 18, 1254e1256.
3.2.3. Synthesis of tetranaphthalide 4. A mixture of 1-hydroxy-2-
naphthoic acid 5 (2.8 g, 15 mmol), POCl3 (3 mL, 30 mmol) and tol-
uene (30 mL) was heated under reflux for 6 h. After cooling the
reaction mixture to room temperature, water was added. The
crystals deposited were separated by filtration and washed with
water and aq NaHCO3 solution. The crystalline solid was purified by
silica gel column chromatography using AcOEt as eluent to give 4 ꢁas1
white solid. Yield 23% (0.7 g); mp>300 ꢀC; IR (Nujol) 1731 cm
3. Toda, F. Acc. Chem. Res. 1995, 28, 480e486; Tanaka, K.; Toda, F. Chem. Rev. 2000,
100, 1025e1074; Organic Solid State Reactions; Toda, F., Ed.; Kluwer: Dordrecht,
2001; Organic Solid State Reactions, Topics in Current Chemistry 254; Toda, F., Ed.;
Springer: Berlin, 2005; MacGillivray, L. R.; Papaefstathiou, G. S.; Friscic, T.;
Hamilton, T. D.; Bucar, D.-K.; Chu, Q.; Varshney, D. B.; Georgiev, I. G. Acc. Chem.
Res. 2008, 41, 280e291; MacGillivray, L. R. In Strategies and Tactics in Organic
Synthesis; Harmata, M., Ed.; Elsevier: Academic, London, 2008; pp 368e382.
4. Dickert, F.; Haunschild, A. Adv. Mater. 1993, 5, 887e895; Meinhold, D.; Seichter,
W.; Kohnke, K.; Seidel, J.; Weber, E. Adv. Mater. 1997, 9, 958e961; Pirondini, L.;
Dalcanale, E. Chem. Soc. Rev. 2007, 695e706.
5. Gutsche, C. D. In Calixarenes; Stoddart, J. F., Ed.; Royal Society of Chemistry:
Cambridge, 1989; Calixarenes 2001; Asfari, Z., Bohmer, V., Harrowfield, J.,
Vicens, J., Saadioui, M., Eds.; Kluwer: Dordrecht, 2001.
6. Chen, Y.; De-Xian, W.; Zhi-Tang, H.; Mei-Xiang, W. J. Org. Chem. 2010, 75,
3786e3796.
(C]O); 1H NMR (CDCl3, 400 MHz)
J¼8.8 Hz, 4H, Ar), 7.86 (s, 4H, Ar), 7.65 (s, 4H, Ar), 7.35 (d, J¼8.8 Hz,
4H, Ar); 13C NMR (CDCl3, 67.8 MHz)
164.5, 148.9, 137.2, 129.3,
d 8.87 (s, 4H, Ar), 7.91 (d,
d
127.8,127.7,127.4,127.2,126.5,123.4,117.7. Anal. Calcd for C44H24O8:
C 77.64, H 3.55; found: C 77.38, H 3.74; MS (ESI) m/z: 687.26 [MþLi];
719.35 [MþK].
7. Morohashi, N.; Narumi, F.; Iki, N.; Hattori, T.; Miyano, S. Chem. Rev. 2006, 106,
5291e5316.
3.3. X-ray structure determinations
8. Tue, H.; Ishibashi, K.; Tokita, S.; Takahashi, H.; Matsui, K.; Tamura, R. Chem.d
Eur. J. 2008, 14, 6125e6134.
9. Gong, B. Chem.dEur. J. 2001, 7, 4336e4342; Gong, B. Acc. Chem. Res. 2008, 41,
1376e1386.
X-ray diffraction data for 3a$(DMSO)5 were collected on a Non-
ius Kappa CCD diffractometer while those for 3b$(DMSO)2 were
collected on a Bruker Apex Duo diffractometer. The crystal speci-
mens were cooled to their respective low temperatures in a con-
stant stream of nitrogen vapour. Unit cell refinements and data
reductions were performed with DENZO-SMN11 and SAINTþ.12
10. Tanaka, K.; Hayashi, S.; Caira, M. R. Org. Lett. 2008, 10, 2119e2122.
11. Otwinowski, Z.; Minor, W. Methods Enzymol. 1997, 276, 307e326.
12. Bruker, SAINTþ. Version 7.12; Bruker AXS: Madison, Wisconsin, USA, 2008.
€
13. Program SADABS, Version 2.05; University of Gottingen: Germany, 1997.
14. Sheldrick, G. M. Acta Crystallogr. 2008, A64, 112e122.