Synthesis of diverse N, O-bridged calix[1]arene[4]pyridine-C60 dyads and triads and formation of intramolecular self-inclusion complexes

Article abstract of DOI:10.1021/jo1019267

Starting from both the bridging nitrogen atom-functionalized and the upper rim-functionalized N,O-bridged calix[1]arene[4]pyridine reactants, different types of heteracalixaromatics-C₆₀ dyads and triads of varied spacers were expediently synthesized using mainly the click reaction as the key step. By means of various spectroscopic methods, the heteracalixaromatics-C₆₀ dyads and triads obtained have been shown to form intramolecular self-inclusion complexes rather than oligomers or polymers in solution because of a flexible spacer in between the heteracalixaromatic ring and C₆₀ moiety. The current study, coupled with previous investigations, would provide the guideline for the construction of supramolecular fullerene motifs based on molecular design of the dyads and triads.

Full text of DOI:10.1021/jo1019267

pubs.acs.org/joc
Synthesis of Diverse N,O-Bridged Calix[1]arene[4]pyridine-C Dyads
and Triads and Formation of Intramolecular Self-Inclusion Complexes
60
†
Jin-Cheng Wu, De-Xian Wang,* Zhi-Tang Huang, and Mei-Xiang Wang*
,†
†
,†,‡
†
Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and
Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China, and
The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education),
‡
Department of Chemistry, Tsinghua University, Beijing 100084, China
dxwang@iccas.ac.cn; wangmx@mail.tsinghua.edu.cn
Received September 29, 2010
Starting from both the bridging nitrogen atom-functionalized and the upper rim-functionalized
N,O-bridged calix[1]arene[4]pyridine reactants, different types of heteracalixaromatics-C60 dyads and
triads of varied spacers were expediently synthesized using mainly the click reaction as the key step.
By means of various spectroscopic methods, the heteracalixaromatics-C60 dyads and triads obtained
have been shown to form intramolecular self-inclusion complexes rather than oligomers or polymers
in solution because of a flexible spacer in between the heteracalixaromatic ring and C60 moiety. The
current study, coupled with previous investigations, would provide the guideline for the construction
of supramolecular fullerene motifs based on molecular design of the dyads and triads.
Introduction
for example, a few macrocyclic fullerene receptors such as
3
azacrown ethers, calixarenes, cyclotriveratrilenes (CTV),
4
5
Recent years have witnessed an increasing interest in fullerene
6
7
triptycenes, cyclodextrins (CD), and carbon nanorings
8
1
chemistry. Along with the very rapid and enormous devel-
opment of functionalizations of fullerenes via the formation
2
of various covalent bonds, supramolecular fullerene chemistry
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3
or the nonchemical bonding interactions between fullerenes
and synthetic host molecules has also attracted consider-
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(
(
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604 J. Org. Chem. 2010, 75, 8604–8614
Published on Web 11/18/2010
DOI: 10.1021/jo1019267
r 2010 American Chemical Society

Wu et al.
JOCArticle
have been investigated. Porphyrins and metalloporphyrins
with planar π-surfaces are also found to form complexes with
fullerenes. Bis-macrocyclic molecules, such as bisporphyrins
potentially useful optoelectronic materials, though very few,
have been constructed by means of host-guest interactions.
For example, Liu and co-workers have reported the first
example of a water-soluble fullerene assembly between full-
9
1
0
11
“Jaws”) and biscalixarenes, have been explored to enhance
(
1
2
the power of complexation with fullerenes. It is noteworthy
that fullerene-based supramolecular oligomers and polymers,
erenes and rigidified dimeric cyclodextrins. The comple-
mentary molecular interaction between C60 and calix[5]arenes
has been applied as a driving force for the preparation of a
1
1c
self-assembly network. Li and co-workers reported molec-
ular assembly of zinc porphyrin-based molecular tweezers
13
with fullerenes and derivatives.
(
7) (a) Andersson, T.; Nilsson, K.; Sundahl, M.; Westman, G.;
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As a new generation of macrocyclic host molecules, hetera-
14-18
calixaromatics have recently received fast growing interest.
Because of the different electronic nature of heteroatoms com-
pared with those of carbon, the heteroatom bridged calix-
(
Reed, C. A. J. Org. Chem. 1997, 62, 3642. (b) Olmstead, M. M.; Costa, D. A.;
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(hetero)aromatics exhibit interesting structural and molecular
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2
The bridging nitrogen atoms, for example, can adopt sp and
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3
sp electronic configurations and can form different degrees
of conjugation with the adjacent aromatic rings, leading to
the formation of versatile and fine-tuned macrocyclic struc-
14a,15d
tures and cavities.
Furthermore, various electronic effects
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ent guests.
While macrocycles of a small cavity such as azacalix[4]pyridine
1
Commun. 2002, 402. (c) Haino, T.; Matsumoto, Y.; Fukazawa, Y. J. Am.
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5d-f,l-q,16a,16k,16o-16q
(
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do not interact with fullerene C , azacalix[n]pyridines
6
0
2
(
n = 5-10) and azacalix[4]arene[4]pyridine are powerful host
(
molecules to complex with fullerenes C60 and C70 in solution.
Very recently, we reported that N,O-bridged calix[1]arene-
(
[4]pyridines, unusual heteracalixaromatics bearing an odd
number of different aromatic rings, form a 1:1 complex with
2
1
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(
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-1 18f
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4
9,494 M
.
The easy preparation and functionalization
of N,O-bridged calix[1]arene[4]pyridines both on the upper
rim position (aromatic ring) and on the bridging nitrogen
atom render these novel macrocylcles a unique platform for
the construction of sophisticated molecular architectures.
Our interest in the supramolecular fullerene chemistry,
9
2
(
(
particularly in the construction of heteracalixaromatics-C60
complexes at both small molecular and oligomeric or poly-
meric levels, led us to undertake the present work. Herein we
report the expedient synthesis of N,O-bridged calix[1]arene-
[
4]pyridine-C60 dyads and triads containing different spacers
mainly using click reaction as a key step. Interestingly, the
resulting novel heteracalixaromatics-C60 dyads and triads
all form self-inclusion complexes rather than the “head-to-tail”
supramolecular oligomers and polymers because of the soft
and flexible spacers.
(
p) Vale, M.; Pink, M.; Rajca, S.; Rajca, A. J. Org. Chem. 2008, 73, 27. (q) Yao,
B.; Wang, D.-X.; Huang, Z.-T.; Wang, M.-X. Chem. Commun. 2009, 2899.
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(
M.-X.; Yang, H.-B. J. Am. Chem. Soc. 2004, 126, 15412. (b) Katz, J. L.;
Feldman, M. B.; Conry, R. R. Org. Lett. 2005, 7, 91. (c) Katz, J. L.; Selby, K. J.;
Conry, R. R. Org. Lett. 2005, 7, 3505. (d) Katz, J. L.; Geller, B. J.; Conry, R. R.
Org. Lett. 2006, 8, 2755. (e) Maes, W.; Van Rossom, W.; Van Hecke, K.; Van
Meervelt, L.; Dehaen, W. Org. Lett. 2006, 8, 4161. (f ) Hao, E.; Fronczek, F. R.;
Vicente, M. G. H. J. Org. Chem. 2006, 71, 1233. (g) Chambers, R. D.; Hoskin,
P. R.; Kenwright, A. R.; Khalil, A.; Richmond, P.; Sandford, G.; Yufit, D. S.;
Howard, J. A. K. Org. Biomol. Chem. 2003, 2137. (h) Chambers, R. D.; Hoskin,
P. R.; Khalil, A.; Richmond, P.; Sandford, G.; Yufit, D. S.; Howard, J. A. K.
J. Fluorine Chem. 2002, 116, 19. (i) Li, X. H.; Upton, T. G..; Gibb, C. L. D.;
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K.-Y.; Yang, L.; Li, J.-H.; Chen, L.-J.; You, J.-S. Eur. J. Org. Chem. 2006, 1109.
Results and Discussion
Having functionalized N,O-bridged calix[1]arene[4]pyridines
18f
in hand, we decided to employ the click reaction strategy to
(17) For a review on thiacalixarenes, see: Morohashi, N.; Narumi, F.; Iki,
N.; Hattori, T.; Miyano, S. Chem. Rev. 2006, 106, 5291.
(
2
(
k) Wang, Q.-Q.; Wang, D.-X.; Zheng, Q.-Y.; Wang, M.-X. Org. Lett. 2007, 9,
847. (l) Katz, J. L.; Geller, B. J.; Foster, P. D. Chem. Commun. 2007, 1026.
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008, 10, 585. (o) Yang, H.-B.; Wang, D.-X.; Wang, Q.-Q.; Wang, M.-X. J. Org.
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B.; R o€ del, M.; Bubenitschek, P.; Jones, P. G.; Thondorf, I. J. Org. Chem. 1995, 60,
7406. (b) K o€ nig, B.; R o€ del, M.; Bubenitschek, P.; Jones, P. G. Angew. Chem., Int.
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Z.-T.; Wang, M.-X. Tetrahydron Lett. 2009, 50, 7209.
2
Chem. 2007, 72, 3757. (p) Hou, B.-Y.; Wang, D.-X.; Yang, H.-B.; Zheng, Q.-Y.;
Wang, M.-X. J. Org. Chem. 2007, 72, 5218.(q)Hou, B.-Y.;Zheng, Q.-Y.;Wang,
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Wen, K. J. Am. Chem. Soc. 2009, 131, 8338.
J. Org. Chem. Vol. 75, No. 24, 2010 8605

Wu et al.
JOCArticle
SCHEME 1. Synthesis of 3 and 6
0
SCHEME 2. Synthesis of C60 derivatives 7 and 7
0
Information, Scheme S1), the C60 derivatives 7 and 7 were
prepared (Scheme 2). The CuI-catalyzed 1,3-dipolar cyclo-
addition reaction of alkynes 3 and 6 with azide 7 produced
the desired N,O-bridged calix[1]arene[4] pyridine-C60 dyads
8
and 9 in 98% and 97% yield, respectively (Scheme 3).
Encouraged by the efficient synthesis of 8 and 9, we then
attempted the preparation of N,O-bridged calix[1]arene-
4]pyridine-C60 triads. The diazide compound 10 was first
[
obtained from the Bingel reaction between C60 and 2-azido-
ethyl malonate (see Supporting Information, Scheme S2).
The subsequent click reaction of the Bingel adduct 10 with 2
equiv of alkyne 3 led to the almost quantitative formation of
N,O-bridged calix[1]arene[4]pyridine-C60 triad 11 (Scheme 4).
Since the length of a linker between heteracalixaromatics
and C60 moiety may influence the host-guest interactions,
we then synthesized a calix[1]arene[4]pyridine-C60 triad molec-
ule using a shorter spacer. The ester of N,O-bridged calix-
[
1]arene[4]pyridine compound 12, which was synthesized
1
8f
following a literature method, was reduced with LiAlH4
to give a hydroxy compound 13 in 90%. Esterification of 13
upon treatment with malonate dichloride in the presence of
Cs CO as an acid scavenge furnished the biscalix[1]arene-
2
3
0
[4]pyridine 14 in 59% yield. Through the Bingel reaction
0
between 14 and C with DBU as a base, the N,O-bridged
6
0
calix[1]arene[4]pyridine-C60 triad 14 bearing a shorter linker
was obtained in 42% yield (Scheme 5). It should be noted
that both the dyad molecule 8 and triad molecule 11 contain
a linker between the bridging nitrogen of the calixarene and
C , whereas in the case of dyad molecule 9 and triad molec-
construct heteracalixaromatics-C dyads and triads. Scheme 1
60
illustrates the synthesis of the acetylene components. The alkene
group on the bridging nitrogen atom of macrocycle 1 was
converted to primary alcohol 2 in an excellent yield after
hydroboration and oxidation. In the presence of NaH, nucleo-
philic substitution reaction of 2 with propargyl bromide affor-
ded a terminal alkyne product 3 almost quantitatively. Follow-
ing the same procedures, acetylene compound 6 was prepared
equally efficiently from 4 (Scheme 1).
6
0
ule 14 the spacer is connected to the upper rim position of the
benzene ring of the calixarene macrocycle.
For the purpose of comparison study, two N,O-bridged
0
0
calix[1]arene[4] pyridine derivatives 8 and 9 and a biscalix-
0
[
1]arene[4]pyridine compound 11 , which all contain no full-
1
9
erene moiety, were also synthesized efficiently applying the
same click reaction method (Scheme 6).
The structure of all products including the N,O-bridged
By means of Bingel reaction between C60 and diethyl
malonate and azido-containing malonate (see Supporting
0
0
0
0
calix[1]arene[4] pyridines 8 , 9 , 11 , and 14 , the correspond-
ing heteracalixaromatics-C60 dyads 8 and 9, and triads 11
and 14 was established on the basis of their spectroscopic
(19) (a) Hooper, N.; Beeching, L. J.; Dyke, J. M.; Morris, A.; Ogden, J. S.;
Dias, A. A.; Costa, M. L.; Barros, M. T.; Cabral, M. H.; Moutiho, A. M. C.
J. Phys. Chem. A 2002, 106 (42), 9968. (b) Bingel, C. Chem. Ber. 1993, 126, 1957.
8
606 J. Org. Chem. Vol. 75, No. 24, 2010

Wu et al.
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SCHEME 3. Synthesis of N,O-Bridged Calix[1]arene[4]pyridine-
C60 Dyads 8 and 9
SCHEME 4. Synthesis of N,O-Bridged Calix[1]arene[4]pyridine-
C60 Triad 11
data and microanalysis (see Supporting Information, Figures
1
S16-S45). The assignment of proton signals in H NMR was
1
1
made by means of H- H COSY NMR technique (see Sup-
porting Information, Figure S1). As illustrated in Figure 1,
introduction of a C60 moiety into heteracalixaromatic deri-
0
0
vatives leads the proton signals H (4.62 ppm), H (8.05 ppm),
a
b
0
0
0
0
0
H (4.46 ppm), H (4.05 ppm), and H (1.13 ppm) in com-
c
11 , and14 with fullerene C and its Bingel adduct with diethyl
60
d
e
0
0
pound 8 to shift downfield to H (4.94 ppm), H (8.11 ppm),
b
malonate 7 . As illustrated in Figure 3 and Figures S4-S5 in
Supporting Information, the interaction of heteracalixarenes
a
H (4.84 ppm), H (4.45 ppm), and H (1.31 ppm), respectively,
c
d
e
in heteracalixaromatics-C60 dyad 8. The greater downfield
derivatives with C60 leads to a marginal blue shift of the
0
0
0
b
shift of the proton signals H (4.58 ppm), H (8.04 ppm,)
maximum absorption (λmax) of 7 at about 488 nm in UV-vis
absorption spectra. The titration of macrocyclic compounds
a
0
0
and H (4.43 ppm) in compound 11 to H (4.98 ppm), H
b
c
a
(
8.09 ppm), and H (4.86 ppm) in heteracalixaromatics-C60
with C , however, gave rise to the gradual quench of fluo-
60
c
triad 11 was also observed (Figure 1). Similar results were
also found in the case of heteracalixaromatics-C60 dyad 9
and triad 14 when their H NMR spectra were compared
rescence intensity (Figure 2 and Figures S6-S10 in Support-
ing Information). Based on the Job’s plot experiments (see inset
in Figure 2 and Figures S6-S10 in Supporting Information),
which gave the stoichiometry of the complex, and the fluo-
rescence titration data, all N,O-bridgedcalix[1]arene[4]pyridine
host molecules formed a 1:1 complex with fullerene C60 with
a binding constant in the range of 34719 ( 1051 to 42041 (
1
0
0
with that of N,O-bridged calix[1]arene[4] pyridines 9 and 14
see Supporting Information, Figures S2 and S3). The down-
(
field shift of the proton signals of dyads and triads indicates
the deshielding effect of C moiety imposed on alkoxy protons,
60
-1
implying the proximity of these substituents to the C60 surface
and therefore the self-inclusion of C60 moiety by heteracalix-
arenes ring(s) (infra vide).
1321 M (Table 1). It is worth noting that the binding ability
0
0
0
0
of macrocyclic compounds 8 , 9 , 11 , and 14 toward C
is comparable with that of the parent N,O-bridged calix-
60
1
8f
As a prelude to the investigation of the molecular inter-
action of heteracalixaromatics-C60 dyads and triads synthe-
sized, we initially studied the interaction of compounds 8 , 9 ,
[1]arene[4]pyridines, demonstrating that the substituent or
a long “tail” attached either on the bridging nitrogen atom or
on the upper-rim position of the benzene ring did not very
0
0
J. Org. Chem. Vol. 75, No. 24, 2010 8607

Wu et al.
JOCArticle
SCHEME 5. Synthesis of N,O-Bridged Calix[1]arene[4]pyridine-C60 Triad 14
much affect the interaction of macrocyclic ring with C . It is
6
The interaction between macrocyclic ring and fullerene
C60 moiety was clearly evidenced by the fluorescence spec-
0
important to address that N,O-bridged calix[1]arene[4]pyridine
0
0
0
derivatives 8 and 11 complexed equally well with the Bingel
0
troscopy. As shown in Figure 4, the parent macrocycles 8
0
adduct of C60 with diethyl malonate 7 under the identical
0
and 11 , upon irradiation, gave a fluorescence emission band
at 408 and 377 nm, respectively. In the presence of 1 equiv of
0
conditions. The binding constants for 1:1 complexes of 8 7 ,
3
0
0
0
0
1
1 7 , and 14 7 were 51224 ( 1441, 54979 ( 1625, and
1224 ( 1441 M , respectively (Table 1).
After revealing the strong complexation of N,O-bridged
C , the fluorescence intensity was quenched almost com-
60
3
3
-
1
5
pletely. Under the identical conditions, the dilute solution of
dyad 8 and triad 11 did not emit at all, indicating a strong
self-quenching effect between macrocycle and C60 moiety.
Similar results of dyad 9 and triad 11 can also be observed in
Figures S11-S12 in Supporting Information. The self-
quenching of the fluorescence emission is most probably
attributed to the intramolecular interaction between N,O-
bridged calix[1]arene[4]pyridine concave and the convex of
C , because the intermolecular interaction was easily ex-
calix[1]arene[4]pyridine derivatives and bis-calix[1]arene-
0
[
4]pyridinewithC and the Bingel adduct 7 , we then examined
60
the interaction of N,O-bridged calix[1]arene[4]pyridine-C60
dyads and triads. Figure 3 and Figures S4-S5 show the UV-vis
spectra of N,O-bridged calix[1]arene[4]pyridine-C60 dyads
and triads. The electronic absorption spectrum of a mix-
0
ture of N,O-bridged calix[1]arene[4]pyridine compounds 8 ,
0
6
0
0
0
9 , 11 , and 14 and the Bingel adduct of C were also
depicted. The absorption of the Bingel adduct of C60 at
cluded in a very dilute solution used. It is also important to
note that the intramolecular quenching of fluorescence of
heteracalixaromatics by the C60 group was most likely via a
“space-to-space” mechanism since the flexible spacers did
6
0
4
4
94 nm shifted hypsochromically to 488, 490, 488, and
87 nm when an equimolar amount of N,O-bridged calix-
0
0
0
0
20
[
1]arene[4]pyridine derivatives 8 , 9 , 11 , and 14 was added,
respectively. A further hypsochromic shift was observed at
78, 486, 483, and 485 nm when C60 and macrocyclic ring was
not favor a “through chemical bond” mechanism.
To shed further light on the interaction of heterocalixacro-
4
matics-C60 dyads and triads, a number of other techniques
were employed. The H NMR spectra of the dyads and
1
covalently bonded to form dyads and triads 8, 9, 11, and 14,
respectively. A weak absorption band in a longer wavelength
region (ca. 690 nm) gave the similar hypsochromic shift
when the Bingel adduct was complexed and bonded with a
macrocyclic ring (Figure 3 and Figure S4 in Supporting
Information).
triads either in different concentrations (0.3-20 mM for 11
and 0.3-10 mM for 14, respectively) (Figures S13-S14 in
(20) Tung, C.-H.; Zhang, L.-P.; Li, Y.; Cao, H.; Tanimoto, Y. J. Am.
Chem. Soc. 1997, 119, 5348 and references therein.
8
608 J. Org. Chem. Vol. 75, No. 24, 2010

Wu et al.
0
SCHEME 6. Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivatives 8 , 9 , and 11
JOCArticle
0
0
Supporting Information) and at varied temperatures
298-218 K) (Figure S15 in Supporting Information) did
model may also best explain the complete quenching of
fluorescence of heteracalixaromatics by C moiety through
(
6
0
2
0
not show noticeable shift of the proton signals. These obser-
vations were in agreement with the formation of an intra-
molecular complex rather than the intermolecular “head-to-tail”
oligomers or polymers. The very slight broadening of the
proton signals at a low temperature was most probably due
to the decrease of the flexibility of the macrocycle structure.
a space-to-space mechanism.
As reported in the literature,
1
1c,12
the formation of supra-
molecular fullerene oligomers is achieved utilizing bis-
cyclodextrin or bis-calix[5]arene with a very rigid linker. The
dominant formation of intramolecular self-inclusion com-
plexes of dyads and triads in the current study is most prob-
ably due to the molecular flexibility. With a soft and flexible
spacer such as an alkylene chain in between host and guest
moieties, intramolecular calixarene-C60 interaction wins
over intermolecular interaction.
1
Diffusion H NMR (DOSY NMR) gave no evidence either
for the intermolecular “head-to-tail” interactions between
dyads or triads. Except for monomeric structures, no other
peaks of larger molecular weights were observed from MAL-
DI-TOF mass spectrometry (Figures S46-S49 in Supporting
Information).
Conclusion
Taking all aforementioned results into consideration, both
N,O-bridged calix[1]arene[4]pyridine-C60 dyads 8 and 9 and
triads 11 and 14 formed the corresponding self-inclusion
complexes rather than intermolecular “head-to-tail” aggre-
gates. We proposed that, instead of forming the extended
conformations such depicted in Schemes 3-5, the dyad and
triad molecules adopt most likely the folded conformations
In summary, we have synthesized both the upper rim-
linked and the bridging nitrogen-linked N,O-bridged calix-
[1]arene[4]pyridine-C60 dyads and triads using click reac-
tion protocol from conveniently available functionalized
heteracalixaromatics. By means of UV-vis and fluorescence
spectroscopy, NMR techniques, and MALDI-TOF mass
spectrometric methods, the novel dyads and triads prepared
have been shown to form dominantly intramolecular self-
inclusion complexes rather than intermolecular interacted
oligomers or polymers. This is most probably because of a
flexible spacer in between the heteracalixaromatics ring and
C60 moiety. The use of a rigid linker in dyads and triads,
which prohibits the folding of the molecular conformation,
would enable the formation of “head-to-tail” supramolecular
(Figure 5). The structures of folded self-inclusion complexes
of dyads and triads in Figure 5 were consistent with the
observation of downfield shift of the alkoxy proton signals
of dyads and triads (see Figure 1 and Figures S2-S3 in Sup-
porting Information) (supra vide), as the alkoxy protons of
dyads and triads are proximal to C60 moiety and experience
the deshielding effect of the buckyball. The folded self-inclusion
J. Org. Chem. Vol. 75, No. 24, 2010 8609

Wu et al.
JOCArticle
1
0
0
FIGURE 1. H NMR spectrum of compounds 8 and 8, 11 and 11.
fullerene aggregates. The outcomes of the current study and
of previous investigations would provide a useful guideline
for the construction of supramolecular fullerene motifs based on
molecular design of the dyads and triads.
of NaOH (2M, 11 mL). Then H
2
O
2
(30%, 17 mL) was added into
the mixture for 1 h. The resulting mixture was kept for 4 h in an ice-
bath and another 4 h at room temperature. Brine (200 mL) was
added to the mixture, and the aqueous phase was extracted with
CH Cl
2
2
twice (200 mL ꢀ 2). The organic phase was washed with
NaOH (2 M) solution three times and then dried with anhydrous
Na SO . After filtration and removal of the solvent, the residue was
chromatographed on a silica gel column with a 1:1 mixture of
Experimental Section
2
4
General Procedure for the Synthesis of N,O-Bridged Calix-
[
1]arene[4]pyridine Derivatives 2 and 5. 9-BBN (15 mmol in 30 mL
THF) was added to a solution of 1 (836 mg, 1.5 mmol) or 4 (900 mg,
.5 mmol) in dry THF (200 mL) under argon protection. The
mixture was reacted for 12 h in an ice-bath followed by the addition
petroleum ether and ethyl acetate as the mobile phase to give pure 2
(813 mg, 94%) or 5 (823 mg, 89%) as a pale yellow solid. Data for 2:
1
1
mp 61-62 °C; H NMR (300 MHz, CDCl
3
) δ 7.56 (t, J
2
=8.0 Hz, J =8.0 Hz, 2H),
1
=4.5 Hz,
J
2
=7.9 Hz, 2H), 7.47 (b, 1H), 7.39 (t, J
1
8
610 J. Org. Chem. Vol. 75, No. 24, 2010

Wu et al.
JOCArticle
0
-5
0
FIGURE 2. Emission spectra (λex = 321 nm) of 8 (3.2 ꢀ 10 M) in the presence of C60 (left) and 7 (right) in toluene at 25 °C. The
-6
concentrations of C60 for curves a-l (from top to bottom) are 0, 1.20, 2.40, 3.60, 4.80, 6.00, 7.20, 8.40, 9.60, 10.80, 12.00, and 15.60 ( ꢀ 10 M).
0
-6
The concentrations of 7 forcurvesa-l (from top to bottom) are 0, 1.20, 2.40, 3.60, 4.80, 6.00, 7.20, 8.40, 9.60, 10.80, 12.00, and 15.60 ( ꢀ 10 M).Insets:
0
0
The up insets are the variation of fluorescence intensity F
(
0
/Fcal of 8 with increasing C60 concentration (left) and with increasing 7 concentration
right). The down insets are the Job plots for 8 C60 (left) and 8 7 (right) complex in toluene solution (total concentration is 2.4 ꢀ 10 M).
0
0
0
-5
3
3
0
0
0
0
0
0
FIGURE 3. Absorption spectra of N,O-bridged calix[1]arene[4]pyridine derivatives 8 and 11 , C60 derivative 7 , 1:1 mixture of 8 and 7 , 11
-3
and 7, and N,O-bridged calix[1]arene[4]pyridine-C60 dyad 8 and triad 11. The concentration for all compounds is 1.0 ꢀ 10 M.
-
1
þ
TABLE 1. Association Constants for the 1:1 Complexation of N,O-Bridged
Calix[1]arene[4]pyridines with Fullerene C60 and Bingel Adduct 7
1617, 1590, 1568 cm ; MS (MALDI-TOF) m/z:619.4 [M þ H] ,
þ þ
34 34 8 4
0
a
641.4 [M þ Na] , 657.4 [M þ K] . Anal. Calcd for C H N O
þ þ
K
R
(1:1 complexation (1:1 complexation
0
K
R
[M þ H] : 618.2703. Found: 618.2708 [M þ H] .
-1
-1
compound
with C60) (M
)
with 7 ) (M
)
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivative 3.
NaH (1440 mg, 60 mmol), 2(863mg, 1.5 mmol), and3-bromoprop-
1-yne (714 mg, 6 mmol) were dissolved in dried THF. The mixture
was stirred for 1 h at room temperature and then refluxed for 3 h.
The mixture was cooled in an ice-bath, and ammonium chloride
0
8
42041 ( 1321
34719 ( 1051
37177 ( 1097
40978 ( 1330
49992 ( 1321
b
54979 ( 1625
51224 ( 1441
0
9
0
0
1
1
1
4
a
(
10 mL) was added slowly. After removal of solvent, water
(100 mL) was added, and the mixture was extracted with CH Cl
three times (100 mL ꢀ 3). The organic phase was dried with
anhydrous Na SO . After filtration and removal of the solvent,
the residue was chromatographed on a silica gel column with a
mixture of petroleum ether and ethyl acetate as the mobile phase
to give pure 3 (876 mg, 95%) as a pale yellow solid: mp 54-55 °C;
H NMR (300 MHz, CDCl ) δ 7.52 (t, J =8.0 Hz, J =7.8 Hz,
1 2
H), 7.49 (t, J= 2.4 Hz, 1H), 7.36 (t, J =7.9 Hz, J =7.9 Hz,
H), 7.34 (t, J=7.9 Hz, 1H), 6.96 (dd, J =8.1 Hz, J =2.2 Hz,
2
2H), 6.60-6.52 (m, 6H), 6.36 (d, J=8.0 Hz, 2H), 4.10 (d, J=2.4
Hz, 2H), 3.88 (t, J=7.5 Hz, 2H), 3.49 (t, J=6.5 Hz, 2H), 3.38 (s,
6H), 2.39 (t, J=2.3 Hz, 1H), 1.71 (quintet, J=7.5 Hz, 2H), 1.62
(quintet, J = 7.5 Hz, 2H), 1.41 (quintet, J = 7.5 Hz, 2H);
NMR (75 MHz, CDCl ) δ 161.4, 157.1, 156.0, 155.7, 154.7,
The association constants were calculated using a Stern-Volmer
equation based on fluorescence titration data. Not determined.
b
2
2
7
6
3
.34 (t, J = 8.2 Hz, 1H), 6.96 (dd, J
.61-6.56 (m, 6H), 6.38 (d, J=8.0 Hz, 2H), 3.91 (t, J=7.4 Hz, 2H),
.61 (t, J=6.4 Hz, 2H), 3.39 (s, 6H), 1.72 (quintet, J=7.5 Hz, 2H),
1 2
= 8.1 Hz, J = 2.2 Hz, 2H),
2
4
13
1
.59 (quintet, J= 7.5 Hz, 2H), 1.72 (quintet, J= 7.5 Hz, 2H);
NMR (75 MHz, CDCl ) δ 161.3, 156.9, 155.9, 155.6, 154.6, 140.5,
38.3, 129.5, 114.5, 114.4, 108.5, 107.9, 106.6, 103.4, 62.8, 48.7, 36.7,
C
1
3
1
2
3
2
2
1
-
1
32.5, 28.2, 23.4; IR (KBr) 3331, 2928, 1590, 1573 cm ; MS
1
þ
þ
(
MALDI-TOF) m/z 576.2 [M þ H] , 598.2 [M þ Na] , 614.2
þ
þ
[
M þ K] . Anal. Calcd for C33
H
33
N
7
O
3
[M þ H] : 575.2645.
þ
1
Found: 575.2649 [M þ H] . Data for 5: mp 69-70 °C; H NMR
1
3
(
7
300 MHz, CD OD) δ 7.74 (t, J=7.9 Hz, 2H), 7.53-7.64 (br, 1H),
C
3
.41 (t, J= 8.0 Hz, 2H), 7.00-7.10 (br, 2H), 6.79 (d, J=8.0 Hz),
.55-6.68 (m, 4H), 6.58 (d, J = 7.9 Hz, 2H), 3.57-3.72 (m, 2H),
3
6
140.5, 138.2, 129.5, 116.6, 114.4, 108.6, 108.0, 106.5, 103.4, 80.1,
74.0, 70.1, 58.0, 48.8, 29.4, 28.3, 23.9; IR (KBr) 3291, 2113,
13
3
(
1
5
.40 (s, 9H), 2.97-3.12 (m, 3H), 1.68-1.97 (m, 2H); C NMR
75 MHz, CDCl ) δ 171.0, 170.6, 160.9, 156.9, 156.0, 155.5, 154.2,
40.8, 138.2, 137.2, 115.6, 15.4, 108.8, 107.5, 106.5, 103.9, 103.6, 58.9,
8.3, 48.4, 44.0, 37.4, 36.8, 35.8, 32.9, 30.9, 29.3; IR (KBr) 3397, 1635,
-1
þ
3
1590, 1564 cm ; MS (MALDI-TOF) m/z 614.4 [M þ H] , 636.4
þ þ
36 35 7 3
[M þ Na] , 652.4 [M þ K] . Anal. Calcd for C H N O : C,
70.45; H, 5.75; N, 15.98. Found: C, 70.73; H, 6.02; N, 15.87.
J. Org. Chem. Vol. 75, No. 24, 2010 8611

Wu et al.
JOCArticle
0
-4
0
-4
FIGURE 4. Fluorescence spectra of N,O-bridged calix[1]arene[4]pyridine derivatives 8 (1.0 ꢀ 10 M) and 11 (1.0 ꢀ 10 M), and of the 1:1
0
0
-4
-4
mixture of 8 and C60, 11 and C60, and of the N,O-bridged calix[1]arene[4]pyridine-C60 dyad 8 (1.0 ꢀ 10 M) and triad 11 (1.0 ꢀ 10 M).
FIGURE 5. Schematic illustration of the intramolecular self-inclusion of the N,O-bridged calix[1]arene[4]pyridine-C60 dyad 8 and triad 11
molecules.
1
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivative 6.
NaH (240 mg, 10 mmol), 5 (618 mg, 1 mmol), and 3-bromoprop-
pale yellow solid: mp 39-40 °C; H NMR (300 MHz, d
6
-DMSO)
δ 8.05 (s, 1H), 7.73 (t, J=7.9 Hz, 2H), 7.40 (t, J=8.2 Hz, 1H),
1
-yne (595 mg, 5 mmol) were dissolved in dried THF. The
7.33 (t, J=8.0 Hz, 2H), 7.22 (t, J=2.1 Hz, 1H), 7.99 (dd, J =
8.2 Hz, J =2.1 Hz, 2H), 6.78 (d, J=8.0 Hz, 2H), 6.56 (d, J=8.2Hz,
1
mixture was stirred for 1 h at room temperature and then refluxed
for 3 h. The mixture was cooled in an ice-bath, and ammonium
chloride (10 mL) was added slowly. After removal of solvent,
water (100 mL) was added, and the mixture was extracted with
CH
with anhydrous Na
2
2H), 6.53 (J=8.0 Hz, 2H), 6.40 (d, J=7.9 Hz, 2H), 4.61 (t, J=
4.7 Hz, 2H), 4.46 (t, J=5.3 Hz, 2H), 4.46 (s, 2H), 4.05 (q, J=7.1
Hz, 2H), 3.78 (t, J=7.1 Hz, 2H), 3.46 (s, 2H), 3.38 (t, J=6.5 Hz,
2H), 3.26 (s, 6H), 1.43-1.67 (m, 4H), 1.27-1.38 (m, 2H), 1.13
2
Cl
2
three times (100 mL ꢀ 3). The organic phase was dried
1
3
SO . After filtration and removal of the
2 4
3
(t, J=7.1 Hz, 3H); C NMR (75 MHz, CDCl ) δ 166.1, 166.0,
solvent, the residue was chromatographed on a silica gel column
with a mixture of petroleum ether and ethyl acetate as the mobile
phase to give pure 6 (604 mg, 92%) as a pale yellow solid: mp
161.2, 156.9, 155.8, 155.5, 154.5, 145.9, 140.6, 138.2, 129.5,
123.1, 116.5, 114.4, 108.4, 107.8, 106.5, 103.4, 70.6, 64.3, 63.3,
61.7, 48.8, 48.7, 41.2, 36.7, 29.4, 28.2, 23.8; IR (KBr) 2933, 1750,
1
-1
þ
7
2
5-76 °C; H NMR (300 MHz, d
6
-acetone) δ 7.75 (t, J=7.9 Hz,
H), 7.40 (t, J=8.0 Hz, 2H), 7.34 (s, 1H), 7.03 (s, 2H), 6.82 (d,
1733, 1599, 1568 cm ; MS (MALDI-TOF) m/z 815.5 [M þ H] ,
þ þ
43 46
837.5 [M þ Na] , 853.6 [M þ K] . Anal. Calcd for C H -
þ
þ
J = 7.9 Hz, 2H), 6.62 (d, J = 8.0 Hz, 2H), 6.51-6.60 (m, 4H),
N O [M þ H] : 815.3624. Found: 815.3612 [M þ H] .
1
0
7
0
3
2
.89-4.30 (m, 2H), 3.48-3.69 (br, 2H), 3.21-3.47 (m, 11H),
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivative 9 .
Diisopropylethylamine (5 mL) and CuI (86 mg, 0.4 mmol) were
added to a solution of 6 (142 mg, 0.2 mmol) and 2-azidoethyl
1
3
.84-3.06 (m, 4H), 1.67-1.98 (m, 2H); C NMR (75 MHz,
CDCl ) δ 170.6, 160.9, 156.9, 156.1, 155.4, 154.3, 140.7, 138.3,
3
1
38.1, 115.4, 115.3, 115.0, 108.7, 107.6, 106.6, 103.5, 79.7, 74.5,
7.7, 66.7, 58.1, 48.6, 45.2, 37.9, 36.8, 35.9, 33.0, 28.4, 27.1; IR
3
ethyl malonate (80 mg, 0.4 mmol) in CHCl (10 mL). The
6
(
mixture was stirred for 2 h at room temperature. After filtration
and removal of the solvent, the residue was chromatographed
on a silica gel column with a mixture of acetone and dichloro-
-
1
KBr) 3291, 3225, 2113, 1630, 1590, 1568 cm ; MS (MALDI-
þ
þ
þ
TOF) m/z 657.4 [M þ H] , 679.4 [M þ Na] , 695.4 [M þ K] .
Anal. Calcd for C37 : C, 67.67; H, 5.53; N, 17.06.
Found: C, 67.62; H, 5.65; N, 17.22.
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivative 8 .
Diisopropylethylamine (5 mL) and CuI (153 mg, 0.8 mmol) were
added to a solution of 3 (245 mg, 0.4 mmol) and 2-azidoethyl
0
H
36
8
N O
4
methane as the mobile phase to give pure 9 (165 mg, 97%) as a
1
pale yellow solid: mp 43-44 °C; H NMR (300 MHz, CD
3
OD)
0
δ 7.66-7.92 (d, J = 27.0 Hz, 1H), 7.63 (t, J = 8.0 Hz, 2H),
7.39-7.51 (d, J = 18.7 Hz, 1H), 7.28 (t, J = 7.7 Hz, 2H), 6.89
(s, 2H), 6.67 (d, J=7.8 Hz, 2H), 6.49 (t, J=8.3 Hz, 4H), 6.40 (t, J=
7.5 Hz, 2H), 4.22-4.61 (m, 6H), 4.02 (m, 2H), 3.51 (t, J=6.2 Hz,
2H), 3.25-3.45 (m, 13H), 2.79-2.96 (m, 3H), 1.63-1.90 (m, 2H),
3
ethyl malonate (161 mg, 0.8 mmol) in CHCl (10 mL). The
mixture was stirred for 2 h at room temperature. After filtration
and removal of the solvent, the residue was chromatographed
on a silica gel column with a mixture of petroleum ether and
1
3
1.10 (q, J = 7.1 Hz, 3H); C NMR (75 MHz, CDCl ) δ 170.3,
3
169.9, 166.1, 165.9, 160.9, 156.9, 155.9, 155.4, 154.3, 145.1, 140.7,
138.1, 123.3, 115.2, 108.8, 107.4, 106.4, 103.5, 68.0, 67.4, 64.3,
0
ethyl acetate as the mobile phase to give pure 8 (320 mg, 98%) as
8
612 J. Org. Chem. Vol. 75, No. 24, 2010

Wu et al.
3.3, 61.6, 48.7, 45.0, 41.2, 37.6, 36.7, 35.7, 32.8, 28.4, 27.2, 14.0;
IR (KBr) 2923, 1750, 1732, 1626, 1595, 1568 cm ; MS (MALDI-
JOCArticle
103.5, 71.2, 70.8, 54.9, 64.5, 63.7, 51.7, 48.8, 48.7, 36.8, 29.5,
6
-
1
-1
28.2, 23.9, 14.3; IR (KBr) 1746, 1732, 1590, 1564 cm ; MS
þ
þ
þ
þ
þ
TOF) m/z 858.6 [M þ H] , 880.6 [M þ Na] , 896.6 [M þ K] .
(MALDI-TOF) m/z 1534.4 [M þ H] , 1556.3 [M þ Na] , 1572.3
þ þ
103 44 10 7
þ
Anal. Calcd for C H N O [M þ H] : 858.3682. Found:
[M þ K] . Anal. Calcd for C H N O [M þ H] : 1533.3467.
þ
4
4
47 11
8
þ
1
8
58.3693 [M þ H] .
Found: 1533.3465 [M þ H] . Data for 9: mp 178-179 °C; H
0
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivative 11 .
Diisopropylethylamine (30 mL) and CuI (153 mg, 0.8 mmol)
NMR (300 MHz, d -DMSO, 380 K) δ 7.98 (s, 1H), 7.70 (t, J=
6
7
.7 Hz, 2H), 7.35 (t, J=7.6 Hz, 2H), 7.18-7.28 (br, 1H), 6.90 (d,
were added to a solution of 3 (245 mg, 0.4 mmol) and bis-
(
J = 1.7 Hz, 2H), 6.78 (d, J = 7.7 Hz, 2H), 6.34-6.63 (m, 6H),
3
2-azidoethyl) malonate (48 mg, 0.2 mmol) in CHCl (10 mL).
4
3
1
1
1
1
1
1
6
2
.85-4.96 (br, 2H), 4.72-4.85 (br, 2H), 4.32-4.51 (m, 4H),
The mixture was stirred for 2 h at room temperature. Then more
bis(2-azidoethyl) malonate (24 mg, 0.1 mmol) was added, and
the mixture was kept for another 1 h. After filtration and
removal of the solvent, the residue was chromatographed on a
silica gel column with a mixture of acetone and dichloromethane
.32-3.50 (m, 5H), 3.30 (s, 3H), 3.26 (s, 6H), 1.59-1.85 (m, 2H),
13
.36 (t, J = 7.0 Hz, 3H); C NMR (75 MHz, CDCl ) δ 170.4,
3
70.4, 163.2, 161.0, 156.9, 156.0, 155.4, 154.3, 145.59, 145.24,
45.16, 145.01, 144.96, 144.87, 144.65, 144.61, 144.58, 144.46,
43.85, 143.79, 143.62, 143.05, 143.00, 142.90, 142.65, 142.16,
42.14, 141.81, 140.91, 140.82, 139.18, 138.61, 138.25, 127.77,
23.2, 115.1, 114.0, 109.0, 108.7, 107.5, 106.6, 106.3, 103.6, 71.3,
0
as the mobile phase to give pure 11 (289 mg, 99%) as a pale
1
yellow solid: mp 65-67 °C; H NMR (300 MHz, d
.04 (s, 2H), 7.72 (t, J=7.9 Hz, 4H), 7.40 (t, J=8.3 Hz, 2H), 7.31
t, J=8.1 Hz, 4H), 7.22 (t, J=1.9 Hz, 2H), 7.69 (dd, J =8.3 Hz,
J2 =1.9 Hz, 4H), 6.76 (d, J=7.8 Hz, 4H), 6.55 (d, J=8.1 Hz,
6
-DMSO) δ
8
8.3, 67.5, 64.8, 64.7, 63.7, 51.8, 48.7, 45.0, 37.8, 36.8, 35.8, 32.9,
8.6, 27.2, 14.2; IR (KBr) 1750, 1715, 1640, 1591, 1569 cm
(
1
-1
;
þ
þ
MS (MALDI-TOF) m/z 1577.5 [M þ H] , 1599.5 [M þ Na] ,
4
5
4
H), 6.52 (d, J=8.3 Hz, 4H), 6.39 (d, J=8.0 Hz, 4H), 4.59 (t, J=
.0 Hz, 4H), 4.43 (m, 8H), 3.76 (t, J=7.0 Hz, 4H), 3.42-3.66 (m,
H), 3.38 (m, 4H), 3.25 (s, 12H), 1.58 (m, 4H), 1.47 (m, 4H), 1.29
þ
þ
1
1
615.5 [M þ K] . Anal. Calcd for C H N O [M þ H] :
1
þ
04 46 11
8
576.3525. Found: 1576.3512 [M þ H] .
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine-C60 Triad 11.
Following the same procedure for the preparation of 8 or 9, 11
1053 mg, 49%) was obtained from the reaction of 3 (851 mg,
13
(
m, 4H); C NMR (75 MHz, d -DMSO) δ 165.8, 160.6, 156.6,
6
1
55.4, 154.7, 154.0, 144.2, 141.3, 138.4, 129.8, 124.0, 116.6, 113.1,
10.0, 107.2, 105.8, 104.3, 79.1, 71.9, 69.5, 63.2, 63.1, 48.2, 47.6,
6.4, 29.5, 28.8, 27.5, 23.2; IR (KBr) 2933, 1750, 1733, 1595,
(
1
3
1
1
1
.388 mmol) as a dark brown solid: mp 149-150 °C; H NMR
-1
þ
(300 MHz, d -DMSO) δ 8.09 (s, 2H), 7.71 (t, J = 8.0 Hz, 4H),
6
567 cm ; MS (MALDI-TOF) m/z 1469.8 [M þ H] , 1491.8
þ
þ
7.40 (t, J=8.1 Hz, 2H), 7.29 (t, J=7.9 Hz, 4H), 7.23 (t, J=2.1 Hz,
2
[
[
M þ Na] , 1507.8 [M þ K] . Anal. Calcd for C79
80 20 10
H N O
þ
þ
1 2
H), 6.98 (dd, J =8.0 Hz, J =2.1 Hz, 4H), 6.75 (d, J=8.1 Hz,
M þ H] : 1469.6439. Found: 1469.6469 [M þ H] .
4
H), 6.53 (d, J = 8.0 Hz, 4H), 6.50 (d, J = 8.0 Hz, 4H), 6.37
General Procedure for the Synthesis of Ν,Ο-Bridged Calix-
1]arene[4]pyridine-C60 Dyads 8 and 9. Under argon protection,
(
6
d, J=8.0 Hz, 4H), 4.68-4.95 (m, 8H), 4.38 (s, 4H), 3.74 (t, J=
.3 Hz, 4H), 3.24 (s, 12H), 1.50-1.62 (m, 4H), 1.39-1.49 (m,
[
a mixture of C60 (500 mg, 0.694 mmol) and dried toluene (500 mL)
was stirred until the C60 was thoroughly dissolved. The flask was
covered with kitchen foil to avoid light. A solution of 2-azidoethyl
1
3
3
4H), 1.31-1.32 (m, 4H); C NMR (75 MHz, CDCl ) δ 162.6,
161.3, 156.9, 155.7, 155.5, 154.5, 145.79, 145.24, 145.17, 144.91,
144.83, 144.66, 144.61, 144.49, 144.45, 143.80, 143.00, 142.93, 412.12,
141.77, 140.94, 140.62, 138.84, 138.25, 129.5, 123.1, 116.6, 114.6,
108.6, 107.8, 106.5, 103.5, 70.9, 10.8, 65.0, 64.4, 60.4, 51.2, 48.7,
ethyl malonate (210 mg, 1.045 mmol) and a solution of CBr
1152 mg, 3.470 mmol) in dried toluene were added consecu-
4
(
tively. Then a solution of DBU (1055 mg, 6.940 mmol) in dried
toluene (approximately 20 mL) was injected slowly to the
mixture during 4 h. The resulting mixture was reacted for
another 6 h. After completion of the reaction, water (500 mL)
was added, and the organic phase was separated and dried with
anhydrous Na SO . After filtration, the mixture was concen-
-
1
36.8, 29.4, 28.2, 23.9; IR (KBr) 1746, 1732, 1595, 1573 cm ; MS
(MALDI-TOF) m/z 2188.3 [M þ H] , 2210.3 [M þ Na] , 2226
þ
þ
þ
þ
[M þ K] . Anal. Calcd for C H N O [M þ H] : 2187.6283.
1
þ
39 79 20 10
Found: 2187.6253 [M þ H] .
2
4
Synthesis of N,O-Bridged Calix[1]arene[4]pyridine Derivative 13.
Under argon protection and at 0 °C, LiAlH (2280 mg, 60
mmol) in THF (100 mL) was added slowly into a solution of 12
trated to approximately 30 mL (Caution! The complete removal
of the solvent caused decomposition of the product). Column
chromatography on a silica gel column eluted with first CS to
4
2
(1686 mg, 3 mmol) in dried THF (100 mL) for 2 h. It was reacted
for another 4 h at 0 °C and then 18 h at room temperature. After
completion of the reaction, the mixture was cooled down to 0 °C
with an ice-bath, ethyl acetate (50 mL) was added for 1 h, and the
mixture was stirred for 2 h. Then methanol (50 mL) was added
for 1 h, and the mixture was reacted for 5 h at 0 °C and 2 h at
remove unconsumed C60 and then with a mixture of CS and
2
CH
approximately 10 mL, CHCl
resulting solution was added 3 (425 mg, 0.694 mmol) or 6 (455 mg,
.694 mmol), CuI (1910 mg, 10 mmol), and diisopropylethyl-
amine (50 mL). The mixture was kept at room temperature for
h. After filtration and removal of solvent, the residue was
2
Cl
2
(1:1) to give a black solution. After concentrating to
3
(130 mL) was added. To the
0
room temperature. CHCl (200 mL) was added for 1 h while
3
6
stirring. After filtration, the filter residue was mixed with
another 200 mL of CHCl and was kept stirring for another
chromatographed on a silica gel column with a mixture of
acetone, dichloromethane and carbon bisulfide (1:3:3) as the
mobile phase to give pure 8 (524 mg, 51%) or 9 (546 mg, 50%) as
3
1 h followed by filtration. The filtrate was combined and dried
with anhydrous Na SO . After removal of organic solvent, the
2
4
1
a dark brown solid. Data for 8: mp 120-121 °C; H NMR (300
residue was chromatographed on a silica gel column with a
mixture of acetone and dichloromethane (1:3) as the mobile
phase to give pure product 13 (1441 mg, 90%) as a white solid:
MHz, d -DMSO) δ 8.11 (s, 1H), 7.73 (t, J=7.9 Hz, 2H), 7.40 (t,
6
J=8.2 Hz, 1H), 7.30 (t, J=7.9 Hz, 2H), 7.23 (s, 1H), 6.99 (dd,
1
J
(
1
=7.9 Hz, J
2
=2.1 Hz, 2H), 6.76 (d, J=7.9 Hz, 2H), 6.46-6.52
m, 4H), 6.38 (d, J = 7.9 Hz, 2H), 4.94 (br, 2H), 4.83 (br, 2H),
mp 210-211 °C; H NMR (300 MHz, CDCl ) δ 7.56 (t, J=7.9
3
Hz, 2H), 7.44 (t, J=1.8 Hz, 1H), 7.40 (t, J=8.0 Hz, 2H), 7.00 (d,
J = 2.1 Hz, 2H), 6.63 (d, J = 7.9 Hz, 2H), 6.59 (d, J = 8.0 Hz,
4H), 6.40 (d, J = 8.0 Hz, 2H), 4.72 (s, 2H), 3.43 (s, 3H), 3.41
4
3
1
.45 (q, J = 6.9 Hz, 2H), 4.41 (s, 2H), 3.76 (t, J = 6.6 Hz, 2H),
.37 (t, J = 6.4 Hz, 2H), 3.25 (s, 6H), 1.52-1.63 (m, 2H),
1
3
13
.41-1.52 (m, 2H), 1.20-1.37 (m, 5H); C NMR (75 MHz,
(s, 6H); C NMR (75 MHz, CDCl ) δ 161.2, 156.9, 156.2, 155.4,
3
CDCl ) δ 163.2, 163.1, 161.2, 156.9, 155.7, 155.5, 154.5, 145.93,
154.4, 143.2, 140.5, 138.1, 114.8, 113.5, 108.3, 107.5, 106.6, 103.4,
64.5, 36.7, 35.8; IR (KBr) 3325, 2907, 1577, 1439 cm ; MS
3
-
1
1
1
1
1
45.26, 145.18, 145.00, 144.96, 144.92, 144.89, 144.82, 144.67,
44.64, 144.58, 144.49, 143.86, 143.82, 143.05, 143.02, 142.92,
42.16, 142.15, 141.82, 141.80, 140.97, 140.85, 140.59, 139.22,
38.64, 138.25, 129.5, 122.9, 116.6, 114.4, 108.5, 107.9, 106.5,
þ
þ
(MALDI-TOF) m/z 534.4 [M þ H] , 556.5 [M þ Na] . Anal.
Calcd for C H N O : C, 67.53; H, 5.10; N, 18.38. Found: C,
27
3
0
7
3
67.16; H, 5.01; N, 18.21.
J. Org. Chem. Vol. 75, No. 24, 2010 8613

Wu et al.
JOCArticle
0
Synthesis of Biscalix[1]arene[4]pyridine 14 . To a mixture of
3 (1066 mg, 2 mmol) and Cs CO (978 mg, 3 mmol) in dried
CH Cl (100 mL) was added a solution of malonyl dichloride 2
Scheme S2 in Supporting Information) (169 mg) in dried
CH Cl
(50 mL) for 3 h at 0 °C under argon protection. After
h of stirring, water (100 mL) was added, and the resulting
was added. The organic phase was separated and dried with
anhydrous Na SO . After filtration and removal of solvent, the
2 4
residue was chromatographed on a silica gel column first with
CS to remove the unconsumed C and then with a mixture of
CS and CH Cl (2:1) as the mobile phase to give pure 14 (163 mg,
42%) as a dark brown solid: mp 226-227 °C; H NMR (300
3
MHz, CDCl ) δ 7.51 (t, J=2.2 Hz, 2H), 7.50 (t, J=7.9 Hz, 4H),
7.35 (t, J = 8.0 Hz, 4H), 7.07 (d, J = 2.0 Hz, 4H), 6.58 (d, J =
8.2 Hz, 4H), 6.55 (d, J=8.6 Hz, 4H), 6.52 (d, J=8.1 Hz, 4H),
1
2
3
0
0
2
2
(
2
60
2
2
2
2
2
1
9
mixture was stirred for 0.5 h. Then the aqueous phase was
extracted with CH Cl three times (100 mL ꢀ 3), and the organic
2
2
2 4
phase was dried with anhydrous Na SO . The residue, after
removal of the solvent, was chromatographed on a silica gel
0
6.33 (d, J=8.0 Hz, 4H), 5.51 (s, 4H), 3.39 (s, 6H), 3.37 (s, 12H);
C NMR (75 MHz, CDCl ) δ 163.2, 161.0, 156.9, 156.2, 155.4,
13
column to give pure product 14 (670 mg, 59%) as a yellow solid:
3
1
mp 120-121 °C; H NMR (300 MHz, CDCl ) δ 7.52 (t, J=7.9 Hz,
154.4, 145.16, 145.10, 145.03, 144.89, 144.83, 144.62, 144.54,
143.7, 142.91, 142.84, 142.1, 141.7, 140.87, 140.68, 139.0, 138.2,
136.5, 116.7, 114.9, 108.4, 107.6, 106.7, 103.3, 71.1, 68.1, 36.8,
3
4
J = 2.1 Hz, 4H), 6.60 (d, J = 7.9 Hz, 4H), 6.56 (d, J = 8.0 Hz,
H), 7.47 (t, J = 2.1 Hz, 2H), 7.37 (t, J = 8.0 Hz, 4H), 6.95 (d,
-
1
8
H), 6.36 (d, J=8.0 Hz, 4H), 5.19 (s, 4H), 3.54 (s, 2H), 3.40 (s,
35.8; IR (KBr) 1751, 1593, 1568, 1434 cm ; MS (MALDI-TOF)
O
1
3
þ
þ
6
1
H), 3.38 (s, 12H); C NMR (75 MHz, CDCl
56.8, 156.1, 155.4, 154.4, 140.6, 138.2, 137.1, 116.0, 114.3, 108.4,
07.5, 106.7, 103.4, 66.4, 41.4, 36.7, 35.9; IR (KBr) 1755, 1738, 1593,
3
) δ 166.0, 161.0,
m/z 1854.4 [M þ H] . Anal. Calcd for C123
H
52
N
14
8
[M þ H] :
þ
1853.4130. Found: 1853,4165 [M þ H] .
1
1
-
1
þ
Acknowledgment. We thank the National Natural Science
Foundation of China (20532030, 20772125), Ministry of Science
and Technology (2007CB808005), and the Chinese Academy
of Sciences for financial support.
568, 1435 cm ; MS (MALDI-TOF) m/z 1135.7 [M þ H] .
þ
Anal. Calcd for C63
1
H
54
N
14
O
8
[M þ H] : 1135.4322. Found:
þ
135.4323 [M þ H] .
Synthesis of Calix[1]arene[4]pyridine-C Triad 14. Under
6
0
0
argon protection, a mixture of C (200 mg, 0.278 mmol) and 14
(
6
0
235 mg, 0.208 mmol) in dried toluene (400 mL) was stirred until
the C60 was thoroughly dissolved. The flask was covered with
kitchen foil to avoid light irradiation. After a solution of CBr4
Supporting Information Available: Experimental details and
1
13
characterizations of products, H and C NMR spectra of pro-
ducts, UV-vis and fluorescence spectra, fluorescence titration
spectra, and variable-temperature NMR of 11 and 14. This
material is available free of charge via the Internet at http://
pubs.acs.org.
(
1152 mg, 3.470 mmol) in dried toluene was added, a solution of
DBU (1055 mg, 6.940 mmol) in dried toluene was injected slowly
for 2 h. After 6 h, the reaction was completed, and water (300 mL)
8
614 J. Org. Chem. Vol. 75, No. 24, 2010