Polyaza[n](1,4)naphthalenophanes and polyaza[n](9,10)anthracenophanes

Article abstract of DOI:10.1016/S0040-4020(02)00180-1

A series of polyaza[n](1,4)naphthalenophanes and polyaza[n](9,10)anthracenophanes have been prepared by using the Fukuyama's protecting group (2- or 4-nitrophenyl sulfonyl) in a one-pot cyclization-deprotection reaction. Global yields for the purified products are comparable with those obtained for other polyazacyclophanes using the tosyl group as the amine protecting group. Their structural study has been carried-out by NMR showing a high rigidity for the smaller cycles and a more dynamic behaviour for the largest member of the series. The free energy barrier for the rotational equilibrium for compound 25 is about 3kcal/mol lower than that calculated for analogous N-tosylated macrocycles.

Full text of DOI:10.1016/S0040-4020(02)00180-1

TETRAHEDRON
Pergamon
Tetrahedron 58 12002) 2839±2846
Polyaza[n] 1,4)naphthalenophanes and
polyaza[n] 9,10)anthracenophanes
a
a
b,p
M. Isabel Burguete, Beatriu Escuder, Enrique Garcõa-EspanÄa, Santiago V. Luisa,p
Â
and Juan F. Miraveta
a
 Á Á
Departament de Quõmica Inorganica i Organica, Universitat Jaume I, ESTCE, 12071 Castello, Spain
b
 Á Á Á
Departament de Quõmica Inorganica, Universitat de Valencia, 46100 Burjassot, Valencia, Spain
Received 5 July 2001; revised 20 December 2001; accepted 11 February 2002
AbstractÐA series of polyaza[n]11,4)naphthalenophanes and polyaza[n]19,10)anthracenophanes have been prepared by using the
Fukuyama's protecting group 12- or 4-nitrophenyl sulfonyl) in a one-pot cyclization±deprotection reaction. Global yields for the puri®ed
products are comparable with those obtained for other polyazacyclophanes using the tosyl group as the amine protecting group. Their
structural study has been carried-out by NMR showing a high rigidity for the smaller cycles and a more dynamic behaviour for the largest
member of the series. The free energy barrier for the rotational equilibrium for compound 25 is about 3 kcal/mol lower than that calculated
for analogous N-tosylated macrocycles. q 2002 Elsevier Science Ltd. All rights reserved.
1. Introduction
role giving place to the existence of p±p and p±cation
interactions. On the other hand, aromatic subunits are also
important for the potential use of those receptors as
¯uorescence chemosensors.5,6 For the achievement of such
properties, the introduction of extended aromatic moieties
like naphthalene or anthracene seems an interesting
structural feature 1Chart 2).
In the last years, we have been involved in the preparation
and study of a new family of nitrogen containing macro-
cycles, the polyaza[n]cyclophanes 1Chart 1).1,2 Those
compounds combine the features of a ¯exible polynitro-
genated moiety, having different protonation degrees
depending on the pH, with the rigidity and preorganization
imposed by the presence of the aromatic spacer. According
to such characteristics, water soluble polyaza[n]cyclo-
phanes have shown to be good ligands for metal cations
as well as for biologically relevant anions such as nucleo-
tides, pyrophosphate or barbiturates.3,4
Originally, the synthesis of this family of compounds was
achieved by a modi®cation of the Richman±Atkins
procedure, starting from a pertosylated polyamine that
was reacted, under basic conditions, with a bis1bromo-
methyl)arene to give the N-protected macrocycles. Further
removal of the protecting group led to the desired poly-
azamacrocycles 1see Scheme 1).1 This procedure was
successful when the arene moiety was benzene or durene;
however, the deprotection conditions were too drastic for
the obtention of those polyazacyclophanes with naphthalene
and anthracene fragments in their structure.7 Apparently, the
naphthylic and anthrylic C±N bonds were especially labile
and, in most of cases, the strongly acidic or reductive
In the formation of the corresponding complexes and supra-
molecular species, the aromatic unit can play an important
Chart 1.
Keywords: polyaza[n]11,4)naphthalenophane; polyaza[n]19,10)anthraceno-
phane; nitrophenyl sulfonyl; polyazacyclophane.
p
Corresponding authors. Tel.: 134-964-728239; fax: 134-964-728214;
e-mail: luiss@qio.uji.es
Chart 2.
0040±4020/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020102)00180-1

2840
M. I. Burguete et al. / Tetrahedron 58 22002) 2839±2846
Scheme 1.
conditions used for the deprotection led to their cleavage.
Only in one case, for compound N222 1mˆ1, nˆ0), the
macrocyclic structure could survive the detosylation using
a HBr/AcOH/PhOH mixture in a yield lower than 20%.
Those disappointing results prompted us in the search of a
different protecting group that would be able to maintain the
high yields of the cyclization step and would require mild
deprotection conditions. Different protecting groups have
been assayed for the substitution of the tosyl group in the
Richman±Atkins procedure such as mesylates, tri¯uoro-
acetates or diethoxyphosphoryl derivatives.8 However,
most of those groups have not found general application
as they also require deprotection under drastic conditions,
the starting materials are not prepared easily and the
ef®ciency of the cyclization step is low. Recently, the
synthesis of some anthracenophanes in a small scale has
been described with the use of the b-trimethylsilylethane
sulfonyl group to protect the nitrogen atoms.9 A few years
ago, Fukuyama described the use of the nosyl group 12- or
4-nitrophenyl sulfonyl) for the protection of primary amino
groups and its removal under very mild conditions. Since
then, its utility has been demonstrated by the use in the
selective protection and activation of polyamines and
other amino derivatives, both in solution and in supported
media, as well as in the preparation of N-functionalized
pyridinophanes, among others.10
Scheme 2.
carbonate as the base, gave the N-pernosylated polyaza[n]
11,4)naphthalenophanes 14±17 and polyaza[n]19,10)anthra-
cenophanes 18±21 1Scheme 2).
The yields obtained are collected in Table 1. As it can be
seen, the p-nosylated polyamines 18b±11b) are obtained in
slightly higher yields than the o-analogues 18a±11a). The
pernosylated polyamines are yellowish solids sparingly
soluble in most solvents, especially the p-nitro substituted
and the longer ones.
As it happened in the case of the tosylated analogues, the
protecting group seems to have multiple functions: ®rst,
protecting the amino functions from the undesired poly-
alkylation as well as increasing the acidity of the primary
NH groups. On the other hand, the bulkiness of the aryl
sulfonyl groups seems to favor the 1:1 cyclization reaction
by preventing the approach of a second polyamine molecule
to the arene. The high yields obtained 1Table 2) in absence
of high dilution conditions cannot be ascribed to any
template effect as they seem to be independent of the
Here we report on the synthesis of polyaza[n]11,4)naphthal-
enophanes and polyaza[n]19,10)anthracenophanes by the
use of o- and p-nitrobenzenesulfonyl as the amine protecting
groups in
reaction.11
a
one-pot macrocyclization±deprotection
Table 1. Yields obtained in the preparation of pernosylated polyamines
2. Results and discussion
Starting polyamine
Pernosylated polyamine
Yield 1%)
4
5
6
7
A22oNs 18a)
A22pNs 18b)
A33oNs 19a)
A33pNs 19b)
A222oNs 110a)
A222pNs 110b)
A323oNs 111a)
A323pNs 111b)
61
81
54
63
53
62
74
86
2.1. Synthesis
The commercially available polyamines 4±7 were protected
by their reaction with 2- or 4-nitrobenzenesulfonyl chloride
in CH2Cl2 using triethylamine as a base 1Scheme 2). Further
reaction of 8±11 with different bis1bromomethyl)arenes
112, 13) in acetonitrile, using anhydrous potassium

M. I. Burguete et al. / Tetrahedron 58 22002) 2839±2846
2841
Table 2. Yields obtained in the cyclization of the pernosylated polyamines
Table 3. Yields obtained in the one-pot synthesis of naphthalenophanes and
anthracenophanes
Cyclophane
Yield 1%)
Cyclophane
Overall yield 1%)a
N22pNs 114b)
N33pNs 115b)
92
46
88
98
90
75
84
94
80
87
N22 122)
N33 123)
18
13
25
28
27
25
11.2
30
N222pNs 116b)
N323oNs 117a)
N323pNs 117b)
AN22pNs 118b)
AN33pNs 119b)
AN222oNs 120a)
AN222pNs 120b)
AN323pNs 121b)
N222 124)
N323 125)
AN22 126)
AN33 127)
AN222 128)
AN323 129)
a
Yields correspond to the global three-steps route: cyclization±deprotec-
tion±conversion into the hydrochloride.
polyamine chain length and it also happened for the
pertosylated analogues, independent of the metal cation
used.1a
2.2. Structural studies
Finally, the deprotection of the macrocycles 14±21 was
attempted via SNAr by using the different thiol nucleophiles
described in the literature 1PhSH, HSCH2COOH,
HSCH2CH2OH) in acetonitrile with potassium carbonate
as a base. The best results were, in general, obtained with
the use of b-mercaptoethanol. Although the yields
obtained were low and the cleavage of the labile C±N
bonds was not completely suppressed, we could obtain the
polyaza[n]11,4)naphthalenophanes 22±25 and the polyaza-
[n]19,10)anthracenophanes 26±29. The low solubility of the
isolated pernosylated compounds, especially the p-nitro
substituted ones in acetonitrile, could be the factor
responsible for those low yields initially observed. The
deprotection conditions were improved by a one-pot
cyclization±deprotection sequence using DMFas the
solvent 1Scheme 3).
NMR spectroscopy was used to analyze the structural
features of compounds 22±29 and similar trends to the
previously described pertosylated precursors were found.
The main structural characteristic of these ansa compounds
is the possibility of rotation of the aromatic moiety that will
depend on the polyamine chain length.7a,12 As it can be seen
in Fig. 1, for naphthalenophane 24 1N222) the rotation of the
polyamine chain around the naphtyl moiety is precluded,
leading to a loss of symmetry in the molecule and thus to
the nonequivalence of the different geminal protons. This
can be clearly seen for the naphthylic protons that appear as
an AB system and also for the polyamine methylene protons
that split into two different signals for each geminal proton.
The same trends were also observed for the smaller cycles of
the series 22 1N22) and 23 1N33) that, obviously, presented
a higher rigidity. 2D NMR experiments 11H±13C HMQC
and HMBC) were carried out for the full assignation of all
the signals and the summary of the selected signals appears
collected in Table 4.
Thus, the pernosylated polyamine and the corresponding
bis1bromomethyl)arene were reacted in DMFwith
anhydrous K2CO3 as the base. After 3 days of reaction at
1008C, the mixture was cooled to room temperature, the
sulfur nucleophile was added and the mixture was stirred
for 15 h. By this way, using HSCH2CH2OH as the nucleo-
phile, compounds 22±29 were obtained with the overall
yields shown in Table 3 after a thorough puri®cation
process. It is important to note that for these kinds of
compounds, a drastic decrease in yields is always obtained,
very often to less than one-half of the yield for the crude
product, when a complete puri®cation is carried out.1a
The rigidity introduced by the aromatic moiety ®xes the
conformation of the polyamine chain arching above the
aromatic plane. In this situation, the protons located over
the B ring will be magnetically shielded as is the case, for
example, of protons 3 in compound 24 1N222): proton H30
11.79 ppm) is shifted 0.21 ppm up®eld from its geminal
proton H3 12.0 ppm). The same effect can be observed for
protons 4, with an up®eld shift of 0.24 ppm. However, in the
case of protons 2 and 20 there is not an appreciable magnetic
difference between them, probably because both are
oriented to the outside of the macrocyclic cavity. The
observed ®eld effects depend on the macrocycle size,
namely, on the distance between the proton and the aromatic
moiety. Thus, the up®eld shifts observed for protons H20
and H30 in compound 22 1N22) are 1.21 and 0.82 ppm,
respectively, both values clearly larger than those observed
for naphthalenophane 24.
Figure 1. Aliphatic region of the 1H NMR spectra 1300 MHz, D2O) for
naphthalenophanes 24.
Scheme 3.

2842
M. I. Burguete et al. / Tetrahedron 58 22002) 2839±2846
Table 4. Assignation of the 1H NMR signals for naphthalenophanes 22±24
Naphthalenophane
Protona
1H d 1ppm)b
Ddc
N22 122)
1, 10
3.79, 4.82
2.3, 1.09
2.82, 2.0
8.18, 7.59, 7.45
3.56, 4.77
2.7
1.03
1.21
0.82
±
1.21
±
2, 20
3, 30
A, B, C
1, 10
N33 123)
2, 20
3, 30
1.0±1.4
1.5±1.8
±
±
Figure 2. VT 1H NMR spectra 1300 MHz, CDCl3) of the naphthylic protons
for naphthalenophane 25.
4, 40
A, B, C
1, 10
8.17, 7.54, 7.2
3.55, 4.45
2.4
2.0, 1.79
1.67, 1.43
8.03, 7.47, 7.27
±
0.89
±
0.21
0.24
±
N222 124)
2, 20
showed the expected average signals 1see Table 5). VT
NMR experiments were carried out in order to measure
the energy barrier associated to this rotational process. As
it can be seen in Fig. 2 for compound 25 the coalescence of
the naphthylic signals occurs at ca. 2658C, the DGc value
being 9.3 kcal/mol.13 This value is 3 kcal/mol lower than
that found for the pertosylated derivative reported before
and con®rms the importance of the steric hindrance caused
by the nitrogen protecting group that plays a fundamental
role in the conformations adopted by the macrocyclic
compounds and probably also in the macrocyclization
reaction.
3, 30
4, 40
A, B, C
a
10, 20,¼ correspond to the geminal protons of each methylene oriented
towards the B-ring of naphthalene.
CDCl3, 200 MHz.
b
c
Difference of the chemical shifts between the geminal protons.
On the other hand, all the protons of the polyamine chain,
with the exception of the naphthylic ones, are shifted
up®eld, in general, with respect to the analogues bearing
benzene as the aromatic group, as a consequence of the
presence of an extra aromatic ring. The naphthylic protons,
as pointed out before, appear as an AB system. In this case,
the low ®eld signal corresponds to a proton unshielded ca.
1 ppm with respect to the other one, as a consequence of
being located in the proximity of the peri protons of the B
ring of naphthalene. The aromatic signals for HA and HB
appear as an AA0BB0 system also re¯ecting the loss of
symmetry.
In the case of polyaza[n]19,10)anthracenophanes 26
1AN22), 27 1AN33), 28 1AN222) and 29 1AN323) a new
symmetry plane is present and no splitting of the NMR
signals was observed. Anyway, the rotation of the poly-
amine chain around the aromatic moiety is precluded by
the presence of an extra aromatic ring. The chemical shifts
for some selected signals of anthracenophane AN323,
naphthalenophane N323, and related paracyclophanes
B323 and D323 are compared in Table 5. As can be seen,
the presence of the anthryl moiety enhances dramatically
the ®eld effects observed before.
Naphthalenophane 25 shows a different situation: the chain
length is large enough to allow the free rotation around the
aromatic system at room temperature and its spectrum
Molecular mechanics calculations were carried out using
the Monte Carlo conformational search method implemen-
ted in Macromodel V7.0 program. The AMBERp and MM2p
force ®elds were used in a chloroform continuous solvent
simulation 1GB/SA).14 The results obtained in the confor-
mational search were in agreement with the NMR studies.
In all cases, energy minimum conformers were found
showing the polyamine chain arching over the aromatic
system 1Fig. 3). The smaller cycles, 22 and 23, presented
more strained structures with larger energy differences
between the conformers found. In particular, within
the energy gap considered, 12 kcal/mol, for those cyclo-
phanes, no conformers were found for which the chain
was signi®cantly deviated from the plane perpendicular to
the aromatic unit. However, for larger cycles, 24 and
especially 25, a higher degree of ¯exibility was found,
namely, several conformers were found in a small energy
range. Thus, for naphthalenophane 25, conformations
1
Table 5. Compared H NMR chemical shifts for some selected signals of
compounds 25 and 29 and the related p-cyclophanes B32311, nˆ1, mˆ1,
RˆH) and D32311, nˆ1, mˆ1, RˆCH3)
Compound
Proton
1H d 1ppm)a
B32311)
D32311)
N323125)
AN323129)
B32311)
1
1
1
1
3
3
3
3
5
5
5
5
3.8
4.03
4.3
4.9
1.31
1.50
1.45
0.9
2.30
2.47
2.2
D32311)
N323125)
AN323129)
B32311)
D32311)
N323125)
AN323129)
1.7
a
CDCl3, 200 MHz.

M. I. Burguete et al. / Tetrahedron 58 22002) 2839±2846
2843
4.2. General procedure for the preparation of
pernosylated polyamines
4.2.1. N,N0,N00,N000-Tetrakis o-nitrobenzenesulfonyl)-1,5,
8,12-tetraazadodecane 11a). solution of 8.4 g
A
138 mmol) of o-nitrobenzenesulfonyl chloride in dry
CH2Cl2 was added to a mixture of 1,5,8,12-tetraazado-
decane 11.66 g, 9.5 mmol) and 5.6 mL of Et3N in 100 mL
of dry CH2Cl2. The reaction mixture was stirred at room
temperature for 30 h. The resulting suspension was ®ltered,
washed several times with NH4Cl and water, and the solu-
tion was vacuum evaporated. The resulting waxy solid was
further puri®ed by column chromatography on silica-gel
1
1CH2Cl2/acetone, 9:1). 74%. H NMR 1200 MHz, DMSO-
d6): 1.7 1m, 4H, ±CH2±CH2±CH2±), 2.9 1m, 4H, CH2±N),
3.3 1m, 4H, CH2±NH), 3.48 1s, 4H, N±1CH2)2±N), 7.7±8.25
1m, 16H, Ar±H). 13C NMR: 28.3, 40.1, 46.0, 46.5, 124.5,
129.4, 129.7, 131.3, 132.6, 134.0, 134.7, 147.7. Anal. Calcd
for C32H34N8S4O16: C, 42.0; H, 3.8; N, 12.3; S, 14.0. Found:
C, 42.4; H, 3.7; N, 12.4; S, 14.3.
Figure 3. Calculated MM2p energy minimum conformations for
naphthalenophanes 22±25.
4.2.2. N,N0,N00,N000-Tetrakis p-nitrobenzenesulfonyl)-1,5,
8,12-tetraazadodecane 11b). 86%. H NMR 1200 MHz,
1
showing considerable chain mobility, often deviated from
the perpendicular plane, were found even at ca. 2 kJ/mol
above the minimum energy conformer.
DMSO-d6): 1.7 1m, 4H), 2.8 1t, 4H), 3.3 1t, 4H), 7.9 1d,
4H, Jˆ9.2 Hz), 8.11 1m, 4H), 8.3 1d, 4H, Jˆ9.2 Hz), 8.46
1m, 4H). 13C NMR: 28.8, 46.6, 47.1, 123.5, 124.5, 125.0,
127.1, 128.1, 144.2, 147.4, 150.0, 154.4. Anal. Calcd for
C32H34N8S4O16: C, 42.0; H, 3.8; N, 12.3; S, 14.0. Found:
C, 42.3; H, 4.0; N, 12.2; S, 14.2.
3. Conclusions
4.2.3. N,N0,N00-Tris o-nitrobenzenesulfonyl)-1,4,7-triaza
heptane 8a). 61%. H NMR 1200 MHz, DMSO-d6): 3.35
1
In conclusion, the present results clearly con®rm the high
potential of the nosyl group as an alternative to the tosyl
group for the protection of amino functionalities and
removal under mild conditions. The problems associated
in many cases with the low solubility of compounds
containing several nosyl groups have been reduced, in our
case, with the use of one-pot procedures that do not require
isolation of the intermediate nosylated macrocycles. Using
this one-pot methodology we have been able to prepare a
series of polyaza[n]naphthalenophanes and polyaza[n]-
anthracenophanes even in a gram scale. Structural analyses
have shown the versatility of their dynamic characteristics
upon selection of the chain length. The study of these
compounds as receptors for different cationic and anionic
guests is currently under investigation and they seem to
have a great potential in metal coordination as well as in
¯uorescence sensing.6b,15
1q, 4H, J1ˆ5.9 Hz, J2ˆ6.1 Hz), 3.56 1t, 4H, Jˆ6.1 Hz), 5.78
1t, 2H, Jˆ5.9 Hz), 7.6±7.9 1m, 9H), 8.0±8.15 1m, 3H). 13C
NMR: 42.2, 48.9, 124.4, 125.5, 131.0, 131.2, 132.9, 133.1,
133.8, 134.3, 147.8. Anal. Calcd for C22H22N6S3O12: C,
40.1; H, 3.4; N, 12.8; S, 14.6. Found: C, 40.2; H, 3.5; N,
12.7; S, 14.8.
4.2.4. N,N0,N00-Tris p-nitrobenzenesulfonyl)-1,4,7-triaza
1
heptane 8b). 81%. H NMR 1200 MHz, DMSO-d6): 2.5±
3.4 1m, 8H), 7.8±8.0 1m, 6H), 8.1±8.4 1m, 6H). 13C NMR:
40.2, 44.1, 123.4, 127.7, 129.2, 144.2, 145.9, 148.7. Anal.
Calcd for C22H22N6S3O12: C, 40.1; H, 3.4; N, 12.8; S, 14.6.
Found: C, 40.3; H, 3.7; N, 12.5; S, 14.5.
4.2.5. N,N0,N00-Tris o-nitrobenzenesulfonyl)-1,5,9-triaza
nonane 9a). 54%. H NMR 1200 MHz, DMSO-d6): 1.82
1
1q, 4H, J1ˆ6.9 Hz, J2ˆ7.3 Hz), 3.14 1q, 4H, J1ˆ7.3 Hz,
J2ˆ6.1 Hz), 3.38 1t, 4H, J1ˆ6.9 Hz), 5.6 1t, 2H,
Jˆ6.1 Hz), 7.6±7.9 1m, 9H), 8.0 1m, 1H), 8.1 1m, 2H). 13C
NMR: 28.9, 40.8, 45.4, 124.3, 125.5, 130.8, 131.0, 132.1,
132.9, 133.4, 133.8, 134.0, 148.0. Anal. Calcd for
C24H26N6S3O12: C, 42.0; H, 3.8; N, 12.2; S, 14.0. Found:
C, 41.9; H, 3.7; N, 12.1; S, 14.1.
4. Experimental section
4.1. General
1H NMR spectra were recorded either with a 200 MHz
Varian Gemini spectrometer or a 300 MHz Varian Mercury
spectrometer. 13C NMR spectra were recorded at 50.3 and
75.4 MHz using the same spectrometers. Elemental analysis
was carried out in a Carlo Erba EA-1108 CHNS-O analyzer.
1,4-Bis1bromomethyl)naphthalene 112) and 9,10-bis1bromo-
methyl)anthracene 113) were prepared as previously
described.7
4.2.6. N,N0,N00-Tris p-nitrobenzenesulfonyl)-1,5,9-triaza
nonane 9b). 63%. H NMR 1200 MHz, DMSO-d6): 1.57
1
1m, 4H), 2.76 1m, 4H), 3.07 1m, 4H), 7.9±8.1 1m, 6H), 8.3±
8.5 1m, 6H). 13C NMR: 28.5, 40.2, 45.8, 124.6, 124.7, 128.0,
128.4, 144.4, 146.1, 149.5. Anal. Calcd for C24H26N6S3O12:
C, 42.0; H, 3.8; N, 12.2; S, 14.0. Found: C, 42.2; H, 3.9; N,
12.4; S, 14.2.

2844
M. I. Burguete et al. / Tetrahedron 58 22002) 2839±2846
4.2.7. N,N0,N00,N000-Tetrakis o-nitrobenzenesulfonyl)-1,4,
7,10-tetraazadecane 10a). 53%. 1H NMR 1200 MHz,
DMSO-d6): 3.35 1m, 4H), 3.5±3.6 1m, 8H), 5.75 1t, 2H),
7.6±7.9 1m, 12H), 8.0±8.15 1m, 4H). 13C NMR: 42.4,
47.8, 49.0, 124.4, 124.8, 125.4, 131.0, 131.1, 131.6, 132.4,
132.5, 132.6, 132.9, 133.1, 133.9, 134.2, 135.9, 147.8,
147.9. Anal. Calcd for C30H30N8S4O16: C, 40.6; H, 3.4; N,
12.6; S, 14.5. Found: C, 41.0; H, 3.6; N, 12.5; S, 14.4.
1200 MHz, DMSO-d6): 1.3 1m, 4H), 1.9 1m, 4H), 2.8 1m,
4H), 4.4 1m, 2H), 5.1 1m, 2H), 7.4 1s, 2H), 7.7 1m, 2H), 8.0±
8.6 1m, 14H). 13C NMR: 27.1, 42.6, 42.9, 50.5, 124.0, 124.3,
124.5, 126.2, 127.1, 131.9, 146.0, 150.2. Anal. Calcd for
C36H34N6S3O12: C, 51.5; H, 4.1; N, 10.0; S, 11.5. Found:
C, 51.3; H, 4.3; N, 9.8; S, 11.7.
4.3.5. N,N0,N0,N000-Tetrakis p-nitrobenzenesulfonyl)-2,5,
8,11-tetraaza[12] 1,4)naphthalenophane 16b). 88%. H
1
4.2.8. N,N0,N00,N000-Tetrakis p-nitrobenzenesulfonyl)-1,4,
7,10-tetraazadecane 10). 62%. 1H NMR 1200 MHz,
DMSO-d6): 2.93 1m, 4H), 3.1±3.5 1m, 8H), 7.9±8.5 1m,
16H). 13C NMR: 45.6, 47.6, 48.6, 123.3, 124.6, 125.0,
127.0, 128.1, 128.6, 129.7, 149.6, 150.0. Anal. Calcd for
C30H30N8S4O16: C, 40.6; H, 3.4; N, 12.6; S, 14.5. Found:
C, 40.4; H, 3.5; N, 12.7; S, 14.4.
NMR 1200 MHz, DMSO-d6): 1.8 1m, 4H), 2.4 1m
broad, 6H), 3.1 1m, 2H), 4.0 1s broad, 2H), 5.4 1s
broad, 2H), 7.27 1s, 2H), 7.64 1m, 2H), 7.85±8.3 1m
broad, 16H), 8.4 1m, 2H). 13C NMR: 44.1, 45.3, 45.6,
50.7, 124.2, 124.6, 128.3, 130.3, 131.3, 132.0, 132.3,
134.3, 147.9, 148.3. Anal. Calcd for C42H38N8S4O16: C,
48.5; H, 3.7; N, 10.8; S, 12.3. Found: C, 48.3; H, 3.6; N,
10.7; S, 12.2.
4.3. General procedure for the preparation of
pernosylated cyclophanes
4.3.6.
N,N0,N00-Tris p-nitrobenzenesulfonyl)-2,5,8-tri-
aza[9] 9,10)anthracenophane 18b). 75%. 1H NMR
1200 MHz, DMSO-d6): 3.1 1m, 4H), 3.6 1m, 4H), 5.4 1s,
4H), 7.3±8.5 1m, 20H). 13C NMR: 45.3, 45.9, 51.8, 123.3,
124.7, 125.6, 126.9, 127.8, 129.1, 134.5, 148.3, 151.5. Anal.
Calcd for C38H32N6S3O12: C, 53.0; H, 3.8; N, 9.8; S, 11.2.
Found: C, 52.8; H, 3.9; N, 9.7; S, 11.3.
4.3.1. N,N0,N00,N000-Tetrakis p-nitrobenzenesulfonyl)-2,6,
9,13-tetraaza[14] 1,4)naphthalenophane 17b). Perno-
sylated polyamine 7 13 g, 3.2 mmol) and K2CO3 14.5 g,
32 mmol) were suspended in re¯uxing acetonitrile
1250 mL). To this mixture, a solution of 1,4-bis1bromo-
methyl)naphthalene 18) 11 g, 3.2 mmol) was added drop-
wise. After the addition was complete, the suspension was
re¯uxed for 72 h and then ®ltered. The solution was vacuum
evaporated to dryness to give the crude product as a yellow-
ish solid which was puri®ed by column chromatography on
4.3.7. N,N0,N00-Tris p-nitrobenzenesulfonyl)-2,6,10-tri-
aza[11] 9,10)anthracenophane 19b). 84%. 1H NMR
1200 MHz, DMSO-d6): 0.85 1m, 4H), 1.7 1m, 4H), 2.9 1m,
4H), 5.25 1s, 4H), 7.5 1m, 2H), 7.7 1m, 4H), 8.0±8.6 1m,
14H). 13C NMR: 29.7, 45.1, 45.8, 52.0, 124.6, 125.0, 125.6,
126.7, 128.0, 128.9, 129.5, 130.4, 131.4, 132.3, 133.6,
142.8, 144.0, 149.9. Anal. Calcd for C40H36N6S3O12: C,
54.1; H, 4.1; N, 9.4; S, 10.8. Found: C, 54.3; H, 4.0; N,
9.6; S, 10.6.
1
silica gel 1CH2Cl2/acetone, 9:1). 13.4 g, 90%). H NMR
1200 MHz, DMSO-d6): 1.25 1m, 4H, ±CH2±CH2±CH2±),
2.5±3.2 1m, 12H, CH2±N), 4.8 1s broad, 4H, Ar±CH2±N),
7.5 1s, 2H, Ar±H), 7.9 1d, 4H, Ar±H), 8.0±8.5 1m, 12 H,
Ar±H). 13C NMR: 28.5, 46.4, 46.7, 47.0, 53.2, 124.3, 124.7,
127.5, 128.0, 130.8, 131.1, 131.2, 131.8, 132.0, 132.2,
132.4, 132.6, 134.0, 134.2, 147.7, 148.6. IR: 3106, 1701,
1598, 1530, 1350, 1159, 853, 739. Anal. Calcd for
C44H42N8S4O16: C, 49.5; H, 4.0; N, 10.5; S, 12.0. Found:
C, 49.8; H, 3.8; N, 10.3; S, 12.2.
4.3.8. N,N0,N00,N000-Tetrakis p-nitrobenzenesulfonyl)-2,5,
8,11-tetraaza[12] 9,10)anthracenophane 20b). 80%. H
1
NMR 1200 MHz, DMSO-d6): 2.6±3.1 1m, 12H), 5.4 1s
broad), 4H), 7.3±7.8 1m, 8H), 7.9±8.7 1m, 16H). 13C
NMR: 45.3 1broad), 46.0, 47.6, 51.1, 124.7 1broad), 126.9,
127.8, 129.0, 129.9, 130.5, 142.4, 143.5, 149.9. Anal. Calcd
for C46H40N8S4O16: C, 50.7; H, 3.7; N, 10.3; S, 11.8. Found:
C, 50.6; H, 3.8; N, 10.1; S, 11.9.
4.3.2. N,N0,N00,N000-Tetrakis o-nitrobenzenesulfonyl)-2,6,
9,13-tetraaza[14] 1,4)naphthalenophane 17a). 98%. H
1
NMR 1200 MHz, DMSO-d6): 1.2 1m, 4H), 2.9±3.3 1m,
8H), 3.5 1s, 4H), 4.9 1s broad), 4H), 7.7 1s, 2H), 7.7±8.2
1m, 14H), 8.45 1m, 2H). 13C NMR: 27.8, 44.7, 45.2, 46.0,
52.3, 124.5, 124.6, 129.8, 131.0, 132.6, 134.7, 135.0, 147.9,
148.1. Anal. Calcd for C44H42N8S4O16: C, 49.5; H, 4.0; N,
10.5; S, 12.0. Found: C, 49.6; H, 3.9; N, 10.3; S, 12.2.
4.3.9. N,N0,N00,N000-Tetrakis p-nitrobenzenesulfonyl)-2,6,
9,13-tetraaza[14] 9,10)anthracenophane 21b). 87%. H
1
NMR 1200 MHz, DMSO-d6): 0.8 1m, 4H), 1.23 1s, 4H),
2.7 1m, 4H), 3.0 1m, 4H), 5.3 1s, 4H), 7.6 1m, 4H), 7.85
1d, 4H, Jˆ9.3 Hz), 8.2±8.4 1m, 8H), 8.6 1d, 4H,
Jˆ8.1 Hz), 8.7 1m, 4H). 13C NMR: 29.7, 45.1, 46.2, 46.4,
56.0, 124.8, 125.1, 125.6, 125.9, 126.8, 128.0, 128.4, 129.5,
130.8, 142.3, 143.9, 150.0, 150.4. Anal. Calcd for
C48H44N8S4O16: C, 51.6; H, 4.0; N, 10.0; S, 11.5. Found:
C, 51.5; H, 4.1; N, 10.1; S, 11.4.
4.3.3. N,N0,N00-Tris p-nitrobenzenesulfonyl)-2,5,8-triaza-
[9] 1,4)naphthalenophane
14b). 92%. 1H NMR
1200 MHz, DMSO-d6): 1.45 1m, 2H), 2.6±3.0 1m, 6H),
4.45 1d, 2H, Jˆ13.5 Hz), 5.54 1d, 2H, Jˆ13.5 Hz), 7.48
1m, 2H), 7.5±7.8 1m, 12H), 8.0 1m, 2H), 8.25 1dd, 2H,
J1ˆ 3.4 Hz, J2ˆ6.5 Hz). 13C NMR: 44.8, 49.4, 51.8,
124.0, 124.2, 124.5, 128.1, 130.3, 131.0, 131.3, 132.0,
132.3, 132.6, 134.1, 147.8, 148.2. Anal. Calcd for
C34H30N6S3O12: C, 50.4; H, 3.7; N, 10.4; S, 11.9. Found:
C, 50.7; H, 3.8; N, 10.6; S, 11.8.
4.3.10. One-pot synthesis of naphthalenophanes and
anthracenophanes: 2,6,9,13-tetraaza[14] 9,10)anthra-
cenophane 29). A solution of 9,10-bis1bromomethyl)-
anthracene 113) 11.4 g, 3.8 mmol) in DMF1100 mL) was
added dropwise to a mixture of N,N0,N00,N000-tetrakis1o-nitro-
benzenesulfonyl)-1,5,8,12-tetraazadodecane 111a) 13.5 g,
3.8 mmol) and anhydrous K2CO3 15.2 g, 38 mmol) in dry
4.3.4. N,N0,N00-Tris p-nitrobenzenesulfonyl)-2,6,10-triaza-
[11]- 1,4)naphthalenophane 15b). 46%. 1H NMR

M. I. Burguete et al. / Tetrahedron 58 22002) 2839±2846
2845
DMF1300 mL) at 90 8C. After stirring at 908C for 3 days, the
mixture was cooled to room temperature and 3 mL
142.9 mmol) of b-mercaptoethanol were added. The
mixture was stirred for 15 h and then ®ltered, and the
solvent was evaporated under reduced pressure. The sticky
solid obtained was poured into 50 mL of 3 M HCl and
washed several times with CH2Cl2. The aqueous layer was
basi®ed, extracted several times with CHCl3 and dryed with
anhydrous MgSO4. The solvent was vacuum evaporated to
dryness and the yellow solid obtained was further puri®ed
by column chromatography 1MeOH:NH3, 10:0.5) giving a
waxy solid that, after bubbling HCl1g) through its
methanolic solution, was characterized as its hydrochloride
salt. 30%. 1H NMR 1300 MHz, D2O): 1.63 1m, 4H, ±CH2±
CH2±CH2±), 2.53 1t, 4H, CH2±N), 2.7 1t1s, 8H, CH2±N),
4.9 1s, 4H, Ar±CH2±N), 7.7 1m, 4H, Ar±H), 8.1 1m, 4H,
Ar±H). 13C NMR 1D2O): 22.9, 42.5, 43.5, 44.3, 45.0, 124.9,
128.8, 131.0. Anal. Calcd for C24H32N4´4HCl: C, 55.2; H,
6.9; N, 10.7. Found: C, 54.8; H, 6.8; N, 10.9.
4.3.16. 2,6,10-Triaza[11] 9,10)anthracenophane 27).
25%. H NMR 1300 MHz, D2O): 0.4 1m, 4H), 1.85 1m,
4H), 2.9 1m, 4H), 5.1 1s, 4H), 7.8 1m, 4H), 8.3 1m, 4H).
13C NMR 1D2O): 21.55, 40.9, 41.5, 42.5, 43.5, 124.4,
124.9, 129.1, 130.4. Anal. Calcd for C22H27N3´3HCl: C,
59.7; H, 6.8; N, 9.5. Found: C, 59.4; H, 6.5; N, 9.8.
1
4.3.17. 2,5,8,11-Tetraaza[12] 9,10)anthracenophane 28).
11.2%. 1H NMR 1300 MHz, D2O): 3.2±3.6 1m broad, 12H),
4.9 1s broad, 4H), 7.76 1m, 4H), 8.1 1m, 4H). 13C NMR
1D2O): 42.3, 45.2, 46.3, 47.1, 124.4, 128.3, 129.3, 130.2,
137.7. Anal. Calcd for C24H35N4´4HCl: C, 54.9; H, 7.5; N,
10.7. Found: C, 54.2; H, 7.3; N, 10.8.
References
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1m, 2H), 2.82 1m, 2H), 3.79 1d, Jˆ13.2 Hz, 2H), 4.82 1d,
Jˆ13.2 Hz, 2H), 7.45 1s, 2H), 7.59 1dd, J1ˆ3.3 Hz,
J2ˆ3.2 Hz, 2H), 8.18 1dd, J1ˆ3.3 Hz, J2ˆ3.2 Hz, 2H). 13C
NMR 1D2O): 49.8, 51.0, 54.6, 124.3, 124.7, 127.3, 132.8.
Anal. Calcd for C16H21N3´3HCl: C, 52.7; H, 6.6; N, 11.5.
Found: C, 52.2; H, 6.9; N, 10.9.
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4.3.12. 2,6,10-Triaza[11] 1,4)naphthalenophane 23).
13%. H NMR 1300 MHz, D2O): 1.26 1m, 4H), 2.25 1m,
1
2. For other examples of polyazacyclophanes containing other
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4H), 2.67 1m, 4H), 3.56 1d, Jˆ13.6 Hz, 2H), 4.77 1d,
Jˆ13.6 Hz, 2H), 7.2 1s, 2H), 7.54 1m, 2H), 8.17 1m, 2H).
13C NMR 1D2O): 30.4, 47.0, 48.0, 53.6, 125.1, 126.1, 132.5,
138.1. Anal. Calcd for C18H25N3´3HCl: C, 55.0; H, 7.2; N,
10.7. Found: C, 54.6; H, 6.9; N, 10.3.
4.3.13. 2,5,8,11-Tetraaza[12] 1,4)naphthalenophane 24).
25%. H NMR 1300 MHz, D2O): 1.43 1m, 2H), 1.67 1m,
Â
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1dd, J1ˆ4.4 Hz, J2ˆ6.6 Hz, 2H), 8.03 1dd, J1ˆ4.4 Hz,
J2ˆ6.6 Hz, 2H). 13C NMR 1D2O): 45.8, 46.3, 47.8, 50.0,
125.6, 127.6, 128.6, 133.0, 137.0. Anal. Calcd for
C18H26N3´3HBr: C, 34.8; H, 4.9; N, 9.0. Found: C, 34.1;
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28%. 1H NMR 1300 MHz, D2O): 1.45 1m, 4H), 2.23 1s, 4H),
2.45±2.5 1m, 8H), 4.29 1s, 4H), 7.37 1s, 2H), 7.55 1dd,
J1ˆ4.4 Hz, J2ˆ6.6 Hz, 2H), 8.25 1dd, J1ˆ4.4 Hz,
J2ˆ6.6 Hz, 2H). 13C NMR 1D2O): 27.4, 45.3, 46.9, 47.2,
49.8, 125.4, 127.6, 128.5, 132.7, 135.5. Anal. Calcd for
C20H30N4´4HCl: C, 50.9; H, 7.3; N, 11.9. Found: C, 50.7;
H, 7.5; N, 11.1.
Â
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Escuder, B.; Domenech, A.; Garcõa-EspanÄa, E.; Luis, S. V.;
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4H), 7.6 1dd, J1ˆ3.5 Hz, J2ˆ3.2 Hz, 4H), 8.2 1dd,
J1ˆ3.5 Hz, J2ˆ3.2 Hz, 4H). 13C NMR 1D2O): 51.0, 51.2,
54.5, 124.0, 124.4, 131.3, 133.5. Anal. Calcd for
C20H23N3´3HCl: C, 57.9; H, 6.3; N, 10.1. Found: C, 57.3;
H, 6.7; N, 9.8.
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Marcelino, V.; Llinares, J. M.; Ramõrez, J. A.; Soriano, C.
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