Mono-ionizable calix[4]arene-benzocrown-6 ligands in 1,3-alternate conformations: synthesis, structure and silver(I) extraction

Article abstract of DOI:10.1016/j.tet.2009.07.006

Two series of novel mono-ionizable calix[4]arene-benzocrown-6 ligands in 1,3-alternate conformations are synthesized. In one series, the proton-ionizable group (PIG) is attached to the para position of one aromatic ring in the calixarene framework, thereby positioning it over the polyether ring cavity. In the other series, the PIG is a substituent on the benzo group in the polyether ring. This orients the PIG away from the crown ether cavity. In addition to carboxylic acid functions, the PIGs include N-(X)sulfonyl carboxamide groups. With X group variation from methyl to phenyl to 4-nitrophenyl to trifluoromethyl, the acidity of the PIG is 'tuned'. Solvent extraction of Ag⁺ from aqueous solutions into chloroform is used to probe the influence of structural variation within the mono-ionizable calixcrown ligand on metal ion extraction efficiency, including the identity and acidity of the PIG and its orientation with respect to the polyether ring.

Full text of DOI:10.1016/j.tet.2009.07.006

Tetrahedron 65 (2009) 7777–7783
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Mono-ionizable calix[4]arene-benzocrown-6 ligands in 1,3-alternate
conformations: synthesis, structure and silver(I) extraction
,
Malgorzata Surowiec a, Radu Custelcean b, Kazmiriez Surowiec a, Richard A. Bartsch a
*
a Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061, USA
b Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6119, USA
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 11 May 2009
Received in revised form 24 June 2009
Accepted 1 July 2009
Available online 7 July 2009
Two series of novel mono-ionizable calix[4]arene-benzocrown-6 ligands in 1,3-alternate conformations
are synthesized. In one series, the proton-ionizable group (PIG) is attached to the para position of one
aromatic ring in the calixarene framework, thereby positioning it over the polyether ring cavity. In the
other series, the PIG is a substituent on the benzo group in the polyether ring. This orients the PIG away
from the crown ether cavity. In addition to carboxylic acid functions, the PIGs include N-(X)sulfonyl
carboxamide groups. With X group variation from methyl to phenyl to 4-nitrophenyl to trifluoromethyl,
the acidity of the PIG is ‘tuned’. Solvent extraction of Agþ from aqueous solutions into chloroform is used
to probe the influence of structural variation within the mono-ionizable calixcrown ligand on metal ion
extraction efficiency, including the identity and acidity of the PIG and its orientation with respect to the
polyether ring.
Ó 2009 Elsevier Ltd. All rights reserved.
1. Introduction
avoiding the need for concomitant transfer a hydrophilic aqueous
phase anion, such as chloride, nitrate or sulfate, into the low po-
Calixarene-crown ether compounds, also called calixcrowns,
combine a calixarene scaffold with a crown ether unit that bridges
two phenolic oxygens of the former with a polyether chain.1–6
Linking of distal phenolic oxygens in calix[4]arenes gives 1,3-
bridged calix[4]crowns, while connection of the proximal oxygens
produces less common, 1,2-bridged calix[4]crown compounds. It
has been found that 1,3-bridged calix[4]crowns exhibit high bind-
ing affinities towards alkali and alkaline earth metal cations.7-9
By use of appropriate substituents, the calix[4]arene platform
may be locked in different conformations (cone, partial cone, 1,3-
alternate and 1,2-alternate). In calix[4]arene-crown compounds,
this controls the spatial relationship between the polyether ring
and constituents of the calixarene moiety, including the aromatic
rings of the calixarene unit itself, as well as substituents with
potential coordination sites attached via the remaining phenolic
oxygens. Of particular interest in our metal ion separations research
program are substituents that bear proton-ionizable groups (PIGs).
When the number of acidic hydrogens in a calixcrown ligand
matches the charge of the metal ion to be complexed, solvent ex-
traction proceeds by an ion-exchange mechanism. Formation of an
electroneutral, ionized ligand-metal ion complex in the organic
diluent markedly enhances the efficiency of metal ion extraction by
larity medium.
In continuation of our studies of metal ion separations by mono-
ionizable calix[4]arene compounds,10–13 we have now synthesized
two series of novel mono-ionizable calix[4]arene-benzocrown-6
ligands in 1,3-alternate conformations (Fig. 1). These two series
have identical crown ether units and calix[4]arene scaffolds in-
cluding two lipophilic octyl groups, but differ in the spatial re-
lationship between the PIG and the polyether unit. In Series 1, the
PIG is a substituent on the benzo group in the polyether ring. This
orients the PIG away from the crown ether cavity. In Series 2, the
PIG is attached to an aromatic ring of the calixarene framework.
This positions the PIG over the polyether ring cavity.
C8H17
O
OC8H17
Series 1
X
H
Y
PIG
H
O
O
Series 2 PIG
O
O
X
O
O
Y
* Corresponding author. Tel.: þ1 806 742 3069; fax: þ1 806 742 1289.
E-mail address: richard.bartsch@ttu.edu (R.A. Bartsch).
Figure 1. Mono-ionizable 1,3-alternate calix[4]ene-benzocrown-6 ligands with two
different positions for the proton-ionizable group (PIG).
0040-4020/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2009.07.006

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M. Surowiec et al. / Tetrahedron 65 (2009) 7777–7783
We now report synthetic routes to these two series of proton-
benzene to give the corresponding acid chloride. Conversion of 4
(C]O at 1687 cmꢀ1) to the acid chloride (C]O at 1749 cmꢀ1) was
monitored by IR spectroscopy, which showed that the acid chloride
was extremely moisture sensitive with conversion back to the acid
4. The crude acid chloride was reacted with sodium salt forms of
commercially available sulfonamides to give the desired 40-[N-
(X)sulfonyl carbamoyl]-25,27-dioctyloxy-26,28-calix[4]arene-benzo-
crown-6 compounds 5–8 in 71–95% yields.
ionizable calixcrown ligands with carboxylic acid and N-(X)sulfonyl
carboxamide PIGs. A solid-state structure of one of the Series 2 li-
gands is presented. The influence of structural variation within the
mono-ionizable calixcrown ligand, including the identity and acidity
of the PIG and its orientation with respect to the polyether ring, on
metal ion complexation efficiency, is probed by solvent extraction of
Agþ from aqueous solutions into chloroform. Agþ was selected as the
metal ion to study due to its reported ability to coordinate at either
ethereal or p
-basic sites in 1,3-alternate calix[4]crown ligands.14
2.2. Synthesis of series 2 ligands
The preparative route to 5-carboxy-26,28-di(octyloxy)-25,27-
calix[4]arene-benzocrown-6 (16) and 5-[N-(X)sulfonyl carbamoyl]-
26,28-di(octyloxy)-25,27-calix[4]arene-benzocrown-6 compounds
17–20 is depicted in Schemes 2 and 3.
2. Results and discussion
2.1. Synthesis of series 1 ligands
The synthetic route for the preparation of 40-carboxy-25,
Br
27-di(octyloxy)-26,28-calix[4]arene-benzocrown-6 (4) and 40-[N-
OBz
b
OBz
a
(X)sulfonyl
carbamoyl]-25,27-di(octylox)y-26,28-calix[4]arene-
c
benzocrown-6 compounds 5–8 in the 1,3-alternate conformation is
presented in Scheme 1.
HO
OH
OH
Br
OH
OHOH
OBz
OBz
BzO
OBz
10
9
Br
Br
a
OBz
d
C8H17
OHOH
O
HO
OH
OC8H17
e
OHOH
1
C8H17
O
HO
H
OBz
OBz
11
OC8H17
OC8
17OHOH
12
OC8H
b
17OHOH
13
O
O
O OTs
2
NC
O
OTs
Scheme 2. Synthesis of precursor 13. Reagents and conditions: a) BzCl, pyridine, rt; b)
Br2, CH2Cl2, rt; c) NaH, C8H17I, DMF, rt; d) KOH, aq EtOH, reflux; e) K2CO3, C8H17I, MeCN,
reflux. (Compound 11 was in a mixture of conformations for which the partial cone
was predominant.).
C8H17O
C8H17O
C8H17O
OC8H17
OC8H17
OC8H17
c
d,e
O
O
O
O
O O
O
O
O
O
O
O
O
O
O
O
O O
X
5
CH3
C8H17O
Br
OC8H17
3
4
6
7
8
C6H5
C6H4-4-NO2
CF3
CN
O
O
O
OTs
OTs
CO2H
C(O)NHSO2X
a
+
O O
O
Scheme 1. Synthesis of 1,3-alternate mono-ionizable di(octyloxy)calix[4]arene-ben-
zocrown-6 ligands 4–8 of series 1. Reagents and conditions: a) K2CO3, C8H17I, MeCN,
reflux; b) Cs2CO3, MeCN, reflux; c) KOH, aq EtOH, reflux; d) (COCl)2, C6H6, reflux; e)
XSO2NH2, NaH, THF, rt.
C8H17
OHOH
O
OC8H17
O
O
Br
14
O
O
13
b
15
In retrosynthetic analysis, the target mono-ionizable 1,3-alter-
nate calix[4]arene-benzocrown-6 ligands 4–8 can be assembled
from a benzopolyether diol fragment with an appropriate sub-
stituent on the 4-position of the benzene ring and a distal dialky-
lated calix[4]arene unit. To obtain the 1,3-alternate conformation,
the two alkyl groups are attached to the calix[4]arene scaffold first
followed by coupling with an activated derivative of the diol unit.
Calix[4]arene was reacted with 4 equiv of 1-iodooctane and
4 equiv of K2CO3 in MeCN at reflux to give a 90% yield of known9
25,27-di(octyloxy)calix[4]arene (1). Bis-1,2-[20-(200-hydroxyethoxy)-
ethoxy]-4-cyanobenzene was prepared by the reported reaction15 of
4-cyanocatechol with 2-(2-chloroethoxy)ethanol and K2CO3 in DMF
and conversion of the resultant diol into ditosylate 2 in a 93% overall
yield for the two steps. Cyclization of dialkylated calix[4]arene 1
with 1.1 equiv of ditosylate 2 and 4 equiv of Cs2CO3 in MeCN at reflux
produced an 86% yield of 40-cyano-25,27-di(octyloxy)-26,28-cal-
ix[4]arene-benzocrown-6 (3) in the 1,3-alternate conformation.15
The conformation of 3 was confirmed by 1H and 13C NMR spectra,
which exhibited for the methylene bridge protons (ArCH2Ar) a sin-
glet at 3.75 ppm and for the anti oriented aromatic rings a singlet at
37.69 ppm, respectively.
C8H17
O
C8H17
O
OC8H17
c, d
OC8H17
O
O
O
O O
O
O
O
O
CO2H
C(O)NHSO2X
X
17 CH3
O
O
O
18 C6H5
16
19 C6H4-4-NO2
20 CF3
Scheme 3. Synthesis of 1,3-alternate mono-ionizable di(octyloxy)calix[4]arene-benzo-
crown-6 ligands 16–20 of series 2. Reagents and conditions: a) Cs2CO3, MeCN, reflux;
b) BuLi, CO2, THF, ꢀ75 ꢁC; c) (COCl)2, C6H6, reflux; d) NaH, XSO2NH2, THF, rt.
One requisite fragment was 5-bromo-25,27-dihydroxy-26,28-
(dioctyloxy)calix[4]arene (13), in which the bromine atom would be
converted later into a carboxylic acid function. The synthesis of cal-
ix[4]arene with a single bromine substituent on the upper rim and
two octyloxygroups on the lower rim is shown in Scheme 2. Reaction
of calix[4]arene with benzoyl chloride in pyridine gave tribenzoate
ester 9 in a partial cone conformation.16 Triester 9 was selectively
brominated on the phenolic aromatic nucleus by reaction with Br2 in
CH2Cl2 at room temperature to give the partial cone conformation
of monobrominated calixarene 1017 in quantitative yield. Alkylation
of 10 with 1-iodooctane and NaH in DMF afforded a 67% yield of
Hydrolysis of nitrile 3 by refluxing with 10% KOH in aqueous
EtOH (1:1, v/v) gave a quantitative yield of 40-(carboxy)-25,27-
di(octyloxy)-26,28-calix[4]arene-benzocrown-6 (4). Calixcrown
carboxylic acid 4 was refluxed with 4 equiv of oxalyl chloride in

M. Surowiec et al. / Tetrahedron 65 (2009) 7777–7783
7779
compound 11 for which the 1H NMR spectrum indicated a mixture of
conformers with the partial cone predominating. The benzoate
protecting groups were removed by refluxing a suspension of 11 with
KOH in aqueous EtOH to produce triphenol 12 in 79% yield. For 12, its
1H NMR spectrum established the cone conformation.
To selectively introduce a second octyl group onto the lower rim
of 12, reaction with 1-iodooctane and the weak base K2CO3 in MeCN
was conducted at reflux for 24 h. In this reaction, the amount of base
was found to be critical. The best yield (74%) was realized when
1.2 equiv of base were added. The proportion of a byproduct in-
creased when a greater amount of base was present. The byproduct
was isolated and characterized by 1H NMR spectroscopy, which
showed it to be a calixarene in the partial cone conformation with
three octyl groups attached to the lower rim. 1H NMR spectroscopy
revealed that the desired product 5-bromo-25,27-dihydroxy-26,28-
di(octyloxy)calix[4]arene (13) was in the cone conformation.
The polyether fragment was prepared by reaction of catechol,
2-(2-chloroethoxy)ethanol, and K2CO3 in DMF to give the corre-
sponding diol,6 which was converted into ditosylate 14.
Utilization of 14 in formation of the calixcrown compound 15 is
shown in Scheme 3. Condensation of the calixarene unit 13 with
the polyether-containing fragment 14 was conducted with 4 equiv
of Cs2CO3 in MeCN at reflux producing a 91% yield of the calixcrown
compound 15, for which the 1,3-alternate conformation was con-
firmed by 1H and 13C NMR spectroscopy. Treatment of 15 with BuLi
in THF at ꢀ78 ꢁC followed by bubbling CO2 through the reaction
mixture gave, after workup and purification, a 62% yield of 5-car-
boxy-26,28-di(octyloxy)-25,27-calix[4]arene-benzocrown-6 (16).
Refluxing calixcrown carboxylic acid 16 with 4 equiv of oxalyl
chloride in benzene gave the corresponding acid chloride, which was
reactedwiththe sodiumsalts ofcommerciallyavailable sulfonamides
to give the mono-ionizable calix[4]arene-benzocrown-6 ligands
17–20 in good yields (50–82%). The conformations of 17–20 were
verified by their 1H and 13C NMR spectra. In the latter, signals for the
methylene bridge carbons were around 37 ppm, which is character-
istic of anti-oriented aromatic nuclei in 1,3-alternate conformers.
Figure 2. Solid-state structure of 5-(N-methanesulfonyl carbamoyl)-26,28-di-
(octyloxy)-calix[4]arene-25,27-benzocrown-6 (17) in the 1,3-alternate conformation.
100
90
80
70
60
50
40
30
20
10
0
2.3. Solid-state structure of ligand 17
The solid-state structure of 5-(N-methanesulfonyl carbamoyl)-
26,28-di(octyloxy)-25,27-calix[4]arene-benzocrown-6 (17) is presented
in Figure 2. As expected, the calixarene ring takes a 1,3-alternate
conformation enforced by the crown ether ring and the two octyl
chains. These chains adopt anti conformations, except for a gauche
conformation involving the ether oxygen and first three methylene
carbons of one octyl group. The PIG is oriented over the crown ether
cavity and forms an intramolecular NH/O hydrogen bond, with
observed N/O and H/O distances of 2.867(4) and 2.202(4) Å, and
an N–H–O angle of 132.1(2)ꢁ.
0
1
2
3
4
pH
5
6
7
8
Figure 3. Percent Agþ loading versus the equilibrium pH of the aqueous phase for Agþ
extraction into chloroform by ligands 4 (,), 5 (6), 6 (B), 7 (7), 8 (>).
2.4. Solvent extraction of AgD
For the calixcrown extractants 5–8 with N-(X)sulfonyl carbox-
amide PIGs, Agþ extraction levels reach at least 85% for 1:1 complex
formation. The extractant efficiency increases with X variation in
the order: MewPh<C6H4-4-NO2ꢂCF3. This is the order of the
electron-withdrawing ability for X.18 Comparison of these extrac-
tion profiles to that for the carboxylic acid calixcrown 5 reveals that
all of the extractants with N-(X)sulfonyl carboxamide PIGs are more
effective in transporting Agþ into the organic phase.
To probe the effects of structural variations within the 1,3-al-
ternate mono-ionizable calix[4]arene-benzocrown-6 compounds
upon metal ion complexation, solvent extraction of Agþ
from aqueous solutions into chloroform was selected. For its com-
plexation by 1,3-alternate calix[4]arene crown ethers, Agþ is of
ambivalent character in that it may accommodate either ethereal or
p
-basic coordination sites.14
For solvent extraction of 1.0 mM aqueous Agþ solutions by
1.0 mM solutions of calixcrown ligands 16–20 (Series 2) in chloro-
form, plots of Agþ loading of the organic phase versus the equilib-
rium pH of the aqueous phase are shown in Figure 4. For the
calixcrown ligands 17–20 with N-(X)sulfonyl carboxamide PIGs,
Agþ extraction levels reach at least 75% for formation of 1:1 com-
plexes. Ligand 20 with X¼CF3 is the most efficient extractant. The
extraction profiles for the other three X groups are very similar.
For solvent extraction of 1.0 mM aqueous Agþ solutions by
1.0 mM solutions of calixcrown ligands 4–8 (Series 1) in chloroform,
plots of Agþ loading of the organic phase versus the equilibrium pH
of the aqueous phase are presented in Figure 3. As expected, all five
ligands are ineffective when the pH of the aqueous phase is very
low. Thus in their un-ionized forms, the calixcrown compounds are
ineffective in transferring Agþ into the organic phase.

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M. Surowiec et al. / Tetrahedron 65 (2009) 7777–7783
cases, there may be a slight favoring of ligands with the PIG
100
90
80
70
60
50
40
30
20
10
0
pointing away from the crown ether cavity, qualifying for an an-
swer of ‘maybe’. For the ligands with a carboxylic acid PIG (Fig. 5a),
the extractant with the ionized group positioned over the crown
ether cavity is clearly more effective. Therefore, the answer is ‘yes’.
The disparate influence of PIG positioning for the carboxylic
acids and for the N(X)-sulfonyl carboxamides as a group, could
result from the ambivalent character of Agþ, which may accom-
modate either ethereal or
p-basic coordinate sites in 1,3-alternate
calix[4]crown ligands.14 A carboxylate function should be a harder
coordination site resulting in Agþ being complexed by both the
ether oxygens and the carboxylate group. In this situation, it be-
comes important for the PIG to be appropriately positioned to in-
teract with a polyether-complexed Agþ. On the other hand, the
ionized N-(X)sulfonyl carboxamide groups should be softer, per-
haps allowing the Agþ to be positioned closer to the
the calixarene framework.
p-basic sites of
0
1
2
3
4
pH
5
6
7
8
3. Experimental
3.1. General
Figure 4. Percent Agþ loading versus the equilibrium pH of the aqueous phase for Agþ
extraction into chloroform by ligands 16 (-), 17 (:), 18 (ꢃ), 19 (;), 20 (A).
Once again the calixcrowns with N-(X)sulfonyl carboxamide PIGs
are found to be more effective Agþ extractants than the corre-
sponding carboxylic acid.
To assess the effect of PIG positioning relative to the crown ether
cavity in the ligands for Agþ extraction, Figure 5 was constructed. In
this figure, the identity of the PIG remains the same but it has two
different positions. In each panel, extraction data for the PIG di-
rected away from the polyether ring (Series 1) are shown as open
circles and those for the PIG positioned over the polyether unit
(Series 2) are presented as filled squares.
Infrared spectra were taken with a Perkin–Elmer 1600 FTIR
spectrophotometer as deposits from CDCl3 or CH2Cl2 solution on
sodium chloride plates. NMR spectra were obtained with a Varian
Unity INOVA 500 MHz FT-NMR (1H 500 MHz and 13C 126 MHz)
spectrometer in CDCl3 with TMS as internal standard. Melting
points were determined with a Mel-Temp melting point apparatus
in capillary tubes. Elemental analysis was performed by Desert
Analytics Laboratory of Tucson, Arizona.
Reagents were purchased from commercial sources and used as
received, unless otherwise specified. Acetonitrile (MeCN) was dried
over CaH2 and tetrahydrofuran (THF) was dried over sodium with
benzophenone as indicator. Both solvents were distilled immedi-
ately before use. N,N-Dimethylformamide (DMF) was stored over
activated 4 Å molecular sieves.
Di-1,2-[20(200-hydroxyethoxy)ethoxy]-4-cyanobenzene was pre-
pared by a literature method.7 The partial cone 28-hydroxy-25,26,
27-tribenzoyloxycalix[4]arene (9)16 and partial cone 5-bromo-28-
hydroxy-25,26,27-tribenzoyloxycalix[4]arene (10)17 were synthe-
sized by reported methods.
Syntheses of the following compounds are described in the
Supplemental data: 1-iodooctane; di-1,2[20(200-hydroxyethoxy)-
ethoxy]-40-cyanobenzene p-toluenesulfonate (2), 1,3-alternate
40-cyano-25,27-di(octyloxy)calix[4]arene-26,28-benzocrown-6 (3),
bis-1,2-[20,200-hydroxyethoxy)ethoxy]benzene, and the ditosylate
of bis-1,2-[20(200-hydroxyethoxy)ethoxy]benzene (14).
100
a
b
c
d
e
90
80
70
60
50
40
30
20
10
0
3.1.1. 1,3-Alternate 40-carboxy-25,27-di(octyloxy)calix[4]arene-
26,28-benzocrown-6 (4)
0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8
pH
A suspension of 3 (1.00 g, 1.08 mmol) in a 10% KOH solution in
1:1 aq EtOH (v/v) (80 mL) was refluxed under nitrogen for 3 h. The
solution was evaporated in vacuo and 5% KOH (30 mL) was added to
the residue along with CH2Cl2 (30 mL). The organic layer was
separated and washed with 1 N HCl (30 mL) then water (30 mL)
and dried over MgSO4. The solvent was evaporated in vacuo
yielding 1.03 g (100%) of 4 as a white solid with mp 102–104 ꢁC. IR:
Figure 5. Comparison of Agþ extraction profiles for series 1 ligands (open circles) and
series 2 ligands (filled squares) with the same PIG: a) carboxylic acids; b) N-meth-
anesulfonyl carboxamides; c) N-benzenesulfonyl carboxamides; d) N-4-nitro-
benzenesulfonyl carboxamides; and e) N-trifluoromethanesulfonyl carboxamides.
Does the PIG position influence the Agþ extraction behavior of
the 1,3-alternate proton-ionizable calix[4]arene-crown-5 ligands?
From the extraction data presented in Figure 5, the answers are
‘yes’, ‘no’ and ‘maybe’. Focusing attention first on Figures 5b and 5c
for N-(X)sulfonyl carboxamide PIGs with X¼Me and Ph, re-
spectively, the data points for the two ligands in each panel es-
sentially define a common line. With no perceptible influence
when the PIG’s position is changed markedly, the answer is ‘no’. In
Figure 5d and e, the behaviors for N-(X)sulfonyl carboxamide PIGs
with X¼C6H4–NO2 and CF3, respectively, are compared. In these
3320–2760 (O–H), 1687 (C]O) cmꢀ1. 1H NMR:
d 7.83 and 7.81 (dd,
J¼1.8, 1.8 Hz, 0.5H), 7.72 (d, J¼1.8 Hz, 0.5H), 7.54 (d, J¼2.0 Hz, 0.5H),
7.43 and 7.41 (dd, J¼2.0, 2.0 Hz, 0.5H), 7.06–6.98 (m, 9H), 6.76 (t,
J¼7.5 Hz, 2H), 6.64 (t, J¼7.5 Hz, 2H), 6.10 (s, 1H), 4.22–4.18 (m, 4H),
3.82–3.72 (m, 12H), 3.57–3.52 (m, 8H), 3.46 (t, J¼7 Hz, 4H), 1.36–
1.24 (m, 20H), 1.19–1.17 (m, 4H), 0.92 (t, J¼7.0 Hz, 6H). 13C NMR:
d
171.0, 156.9, 156.5, 156.2, 156.2, 153.8, 148.4, 134.1, 134.1, 133.8,
133.7, 133.6, 130.0, 129.9, 129.8, 129.7, 125.2, 122.4, 122.1, 121.9,
121.5, 116.0, 112.9, 77.2, 77.0, 76.8, 72.1, 71.0, 70.7, 70.4, 70.3, 70.2,

M. Surowiec et al. / Tetrahedron 65 (2009) 7777–7783
7781
70.0, 69.9, 69.8, 69.4, 68.5, 66.7, 37.7, 36.1, 31.9, 30.2, 29.7, 29.5, 29.4,
26.1, 25.8, 22.7, 15.1, 14.1. Anal. Calcd for C59H74O10: C, 75.13; H, 7.91.
Found: C, 75.31; H, 7.92%.
1.24 (m, 20H), 1.21–1.16 (m, 4H), 0.92 (t, J¼7.0 Hz, 6H). 13C NMR:
d
163.6, 156.9, 156.2, 156.2, 154.1, 150.8, 149.0, 144.0, 134.2, 134.1,
133.7, 133.7, 130.2, 130.1, 129.8, 129.7, 124.2, 123.2, 122.2, 122.1, 121.7,
114.2, 113.0, 77.3, 77.0, 76.8, 71.0, 70.8, 70.5, 70.3, 70.1, 69.8, 69.8,
69.5, 37.6, 31.9, 29.7, 29.5, 29.4, 25.8, 22.7, 14.1. Anal. Calcd for
C65H78N2O13S: C, 69.25; H, 6.97; N, 2.48. Found: C, 69.03; H, 7.07; N,
2.29%.
3.2. General procedure for the preparation of 1,3-alternate 30-
[N-(X)sulfonyl carbamoyl]-25,27-di(octyloxy)calix[4]arene-
26,28-benzocrown-6 compounds 5–8
To a solution of 4 (1.30 g, 1.38 mmol) in dry benzene (25 mL),
oxalyl chloride (0.70 g, 5.51 mmol) was added. The mixture was
refluxed for 5 h under nitrogen and the solvent and excess oxalyl
chloride were evaporated in vacuo to give the corresponding acid
chloride. The appropriate sulfonamide sodium salt (2.07 mmol,
1.5 equiv) was prepared under nitrogen by adding THF (40 mL)
and then NaH (0.13 g, 5.52 mmol). The mixture was stirred at
room temperature for 30 min followed by dropwise addition of
a solution of the acid chloride in THF (20 mL). The mixture was
stirred at room temperature for 12 h. Water (20 mL) was added
and the organic solvent was evaporated in vacuo. To the aq resi-
due, CH2Cl2 (50 mL) was added. The organic layer was separated,
washed with aqueous Na2CO3 (50 mL), dried over Na2SO4 and
evaporated in vacuo. The residue was chromatographed on silica
gel. The product was dissolved in CH2Cl2 (50 mL) and the solution
was washed with 10% HCl (2ꢄ30 mL), dried over MgSO4 and
evaporated in vacuo.
3.2.4. 1,3-Alternate 40-(N-trifluoromethanesulfonyl carbamoyl)-
25,27-di(octyloxy)calix[4]-arene-26,28-benzocrown-6 (8)
Chromatography on silica gel with CH2Cl2/MeOH (40:1) as elu-
ent gave an 88% yield of white solid with mp 88–94 ꢁC. IR: 3550,
3190 (N–H), 1716 (C]O) cmꢀ1. 1H NMR:
d 7.54–7.52 (m, 2H), 7.06–
7.00 (m, 9H), 6.77 (t, J¼7.5 Hz, 2H), 6.63 (t, J¼7.5 Hz, 2H), 4.22 (t,
J¼4.8 Hz, 2H), 4.15 (t, J¼4.8 Hz, 2H), 3.84 (t, J¼4.7 Hz, 2H), 3.75–3.71
(m, 10H), 3.60–3.59 (m, 2H), 3.56–3.53 (m, 6H), 3.47 (t, J¼7.6 Hz,
4H), 1.37–1.24 (m, 20H), 1.20–1.17 (m, 4H), 0.92 (t, J¼7.0 Hz, 6H). 13C
NMR: d 156.96, 156.19, 148.97, 134.19, 134.14, 133.72, 133.69, 130.05,
129.81, 129.67, 122.72, 122.18, 121.77, 115.43, 114.85, 112.93, 77.25,
77.00, 76.74, 70.99, 70.80, 70.43, 70.20, 70.01, 69.87, 69.82, 69.75,
69.53, 37.69, 31.91, 29.70, 29.45, 29.41, 25.85, 22.73, 14.14. Anal.
Calcd for C60H74F3NO11S: C, 67.08; H, 6.94; N, 1.30. Found: C, 67.08;
H, 6.79; N, 1.27%.
3.3. 5-Bromo-28-octyloxy-25,26,27-tri(benzoyloxy)-
calix[4]arene (11)
3.2.1. 1,3-Alternate 40-(N-methanesulfonyl carbamoyl)-25,27-
di(octyloxy)calix[4]arene-26,28-benzocrown-6 (5)
To 1017 (7.00 g, 9.13 mmol) dissolved in DMF (130 mL), NaH
(0.26 g, 10.95 mmol) was added and the mixture was stirred for
30 min at room temperature. Then 1-iodooctane (2.63 g,
10.95 mmol) was added and the mixture was stirred for 24 h at
room temperature. A small amount of water was added carefully to
destroy the excess NaH and then 10% HCl (100 mL) was added. The
organic solvent was evaporated in vacuo. To the aq residue CH2Cl2
(200 mL) was added and the organic layer separated, washed with
10% HCl (100 mL) and then water (2ꢄ100 mL) and dried over
MgSO4. The solvent was evaporated in vacuo. The crude product
was recrystallized from CH2Cl2/MeOH to yield 5.70 g (67%) of 11
Chromatography on silica gel with CH2Cl2/MeOH (30:1) as elu-
ent gave a 71% yield of white solid with mp 115–120 ꢁC. IR: 3267
(N–H), 1687 (C]O) cmꢀ1 1H NMR:
. d 8.65 (br s, 1H), 7.52 (d,
J¼2.2 Hz, 1H), 7.49 and 7.47 (dd, J¼2.1, 2.1 Hz, 1H), 7.06–7.00 (m,
9H), 6.76 (t, J¼7.5 Hz, 2H), 6.62 (t, J¼7.5 Hz, 2H), 4.21 and 4.18 (dt,
J¼5.0, 5.0 Hz, 4H), 3.82 (t, J¼5.0 Hz, 2H), 3.76–3.74 (m, 10H), 3.59–
3.53 (m, 8H), 3.49–3.46 (m, 7H), 1.37–1.25 (m, 20H), 1.21–1.18 (m,
4H), 0.92 (t, J¼7.0 Hz, 6H). 13C NMR:
d 165.0, 157.2, 156.5, 156.4,
156.2, 149.2, 134.4, 134.4, 134.0, 134.0, 130.3, 130.2, 130.0, 124.0,
122.4, 122.3, 122.1, 114.4, 113.3, 77.5, 77.2, 77.0, 71.2, 71.0, 70.7, 70.6,
70.4, 70.1, 70.0, 69.8, 42.1, 37.9, 32.2, 30.0, 29.8, 29.7, 26.1, 23.0, 14.4.
Anal. Calcd for C60H77NO11S: C, 70.63; H, 7.61; N, 1.37. Found: C,
70.57; H, 7.70; N, 1.39%.
with mp 258–260 ꢁC. IR: 1729 (C]O) cmꢀ1 1H NMR:
. d 7.87–7.85
(m, 4H), 7.79–7.76 (m, 2H), 7.65 (t, J¼7.6 Hz, 5H), 7.43–7.42 (m, 2H),
7.36 (t, J¼7.8 Hz, 2H), 7.19–7.17 (m, 2H), 6.81 (s, 2H), 6.70–6.68 (m,
2H), 6.64–6.52 (m, 5H), 3.78 (t, J¼7.7 Hz, 4H), 3.60 (s, 4H), 3.53 (d,
J¼15.0 Hz, 2H), 1.87 (pen, J¼7.3 Hz, 2H), 1.50–1.38 (m, 10H), 0.96 (t,
3.2.2. 1,3-Alternate 40-(N-benzenesulfonyl carbamoyl)-25,27-
di(octyloxy)calix[4]arene-26,28-benzocrown-6 (6)
J¼7.0 Hz, 3H). 13C NMR:
d 164.5, 163.9, 156.3, 148.2, 147.8, 136.2,
Chromatography on silica gel with CH2Cl2/MeOH (30:1) as elu-
ent produced a 95% yield of white solid with mp 92–94 ꢁC. IR: 3264
133.5, 133.5, 133.4, 133.2, 133.0, 132.0, 130.9, 130.8, 130.6, 130.3,
128.8, 128.6, 128.2, 127.6, 125.0, 124.8, 114.9, 77.2, 77.0, 76.7, 71.7,
37.1, 37.0, 31.9, 30.2, 29.8, 29.4, 25.97, 22.8, 14.2. Anal. Calcd for
C57H51BrO7: C, 73.78; H, 5.54. Found: C, 73.90; H, 5.55%.
(N–H), 1694 (C]O) cmꢀ1. 1H NMR:
d 8.20–8.18 (m, 2H), 7.70–7.60
(m, 1H), 7.59–7.56 (m, 2H), 7.47–7.45 (m, 2H), 7.02 (d, J¼7.5 Hz, 8H),
6.94 (d, J¼8.8 Hz, 1H), 6.76 (t, J¼7.5 Hz, 2H), 6.60 (t, J¼7.5 Hz, 2H),
4.16 and 4.10 (dt, J¼4.9, 5.0 Hz, 4H), 3.79–3.69 (m, 12H), 3.54–3.45
(m, 12H), 1.36–1.24 (m, 20H), 1.21–1.18 (m, 4H), 0.92 (t, J¼7.0 Hz,
3.4. Cone 5-bromo-28-octyloxycalix[4]arene (12)
6H). 13C NMR:
d
163.6, 156.9, 156.2, 156.2, 153.6, 148.9, 138.6, 134.1,
Triester 11 (5.70 g, 6.15 mmol) was suspended in 10% KOH so-
lution in aq EtOH (1:1, v/v) and the mixture was refluxed under
nitrogen for 24 h. The mixture was evaporated in vacuo and 5% KOH
(120 mL) was added to the residue along with CH2Cl2 (120 mL). The
organic layer was separated, washed with 1 N HCl (120 mL) then
water (120 mL), dried over MgSO4 and evaporated in vacuo. The
residue was chromatographed on silica gel with hexanes/CH2Cl2
(4:1) as eluent to obtain 3.00 g (79%) of 12 with mp 161–163 ꢁC. IR:
134.1, 134.0, 133.8, 133.7, 130.0, 129.9, 129.7, 129.0, 128.6, 123.9,
122.1, 121.8, 113.8, 113.06, 77.2, 77.0, 76.8, 71.0, 70.7, 70.4, 70.2, 69.8,
69.5, 37.7, 31.9, 29.7, 29.5, 29.4, 25.8, 22.7, 14.1. Anal. Calcd for
C65H79NO11S: C, 72.13; H, 7.36; N, 1.29. Found: C, 71.75; H, 7.37; N,
1.24%.
3.2.3. 1,3-Alternate 40-(N-4-nitrophenylsulfonyl carbamoyl)-25,27-
di(octyloxy)calix[4]-arene-26,28-benzocrown-6 (7)
3317 (O–H) cmꢀ1. 1H NMR:
d 9.53 (s, 1H), 9.31 (s, 2H), 7.17 (s, 2H),
Chromatography on silica gel with CH2Cl2/MeOH (40:1) as elu-
ent produced a 90% yield of yellow solid with mp 105–107 ꢁC. IR:
7.06–7.00 (m, 6H), 6.70 (t, J¼7.5 Hz, 3H), 4.30 and 4.20 (dd, J¼13.1,
13.8 Hz, 4H), 4.11 (t, J¼7 Hz, 2H), 3.47 and 3.43 (dd, J¼13.8, 13.1 Hz,
4H), 2.14 (pen, J¼7.4 Hz, 2H), 1.67 (pen, J¼7.6 Hz, 2H), 1.52–1.46 (m,
3263 (N–H), 1696 (C]O) cmꢀ1. 1H NMR:
d 9.03 (s, 1H), 8.41–8.36
(m, 4H), 7.45–7.42 (m, 2H), 7.02–6.95 (m, 9H), 6.76 (t, J¼7.5 Hz, 2H),
6.58 (t, J¼7.5 Hz, 2H), 4.18 (t, J¼4.8 Hz, 2H), 4.11 (t, J¼4.8 Hz, 2H),
3.81 (t, J¼4.8 Hz, 2H), 3.76–3.69 (m, 11H), 3.56–3.45 (m, 13H), 1.36–
2H), 1.45–1.32 (m, 6H), 0.92 (t, J¼6.9 Hz, 3H). 13C NMR:
d 150.9,
150.8, 149.0, 136.3, 132.13, 129.0, 128.8, 128.7, 128.5, 128.4, 127.5,
122.1, 121.0, 118.4, 77.7, 77.3, 77.0, 76.8, 34.7, 31.8, 31.7, 31.6, 31.3,

7782
M. Surowiec et al. / Tetrahedron 65 (2009) 7777–7783
29.9, 29.4, 29.2, 25.9, 25.3, 22.7, 22.6, 20.7, 14.1. Anal. Calcd for
C36H39BrO4: C, 70.24; H, 6.39. Found: C, 70.42; H, 6.54%.
31.9, 29.8, 29.7, 29.6, 29.4, 29.4, 29.2, 25.8, 25.8, 22.7,14.2,14.4. Anal.
Calcd For C59H74
7.73%.
O10$0.1CH2Cl2: C, 74.59; H, 7.86. Found: C, 74.36; H,
3.5. Cone 5-bromo-26,28-di(octyloxy)calix[4]arene (13)
3.8. General procedure for preparation of 1,3-alternate
5-[N-(X)sulfonyl carbamoyl]-26,28-di(octyloxy)calix[4]-
arene-25,27-benzocrown-6 compounds 17–20
To 12 (3.00 g, 4.88 mmol) dissolved in MeCN (150 mL), 1-
iodooctane (2.34 g, 9.76 mmol) and K2CO3 (0.80 g, 5.85 mmol) were
added. The mixture was refluxed for 24 h and evaporated in vacuo.
The residue was dissolved in CH2Cl2 (150 mL) and 1 N HCl (150 mL)
was added. The organic layer was separated, washed with brine
(2ꢄ150 mL), dried over MgSO4 and evaporated in vacuo. The resi-
due was chromatographed on silica gel with hexanes/CH2Cl2 (6:1)
as eluent to yield 2.60 g (74%) of 13 with mp 138–140 ꢁC. IR: 3349
To a solution of 16 (1.30 g,1.38 mmol) in benzene (25 mL), oxalyl
chloride (0.70 g, 5.51 mmol) was added and the mixture was
refluxed for 5 h under nitrogen. The solvent and excess oxalyl
chloride were evaporated in vacuo. The sodium sulfonamide salt
was prepared under nitrogen by adding NaH (0.13 g, 5.52 mmol)
and THF (40 mL) to the appropriate sulfonamide (2.07 mmol). The
mixture was stirred at room temperature for 30 min followed by
dropwise addition of a solution of the acid chloride in THF (20 mL).
The mixture was stirred at room temperature for 12 h. Water
(20 mL) was added carefully and the organic solvent was evapo-
rated in vacuo. To the residue CH2Cl2 (50 mL) was added. The or-
ganic layer was separated, washed with aqueous Na2CO3 (50 ml),
dried over Na2SO4 and evaporated in vacuo. The crude product was
chromatographed on silica gel. The product was dissolved in CH2Cl2
(50 mL) and the solution was washed with 10% HCl (2 X 30 mL),
dried over MgSO4 and evaporated in vacuo.
(O–H) cmꢀ1. 1H NMR:
d
8.18 (s, 2H), 7.07 and 7.05 (dd, J¼1.3, 1.3 Hz,
2H), 7.01–6.99 (m, 4H), 6.93 (d, J¼7.6 Hz, 2H), 6.76 (t, J¼7.6 Hz, 1H),
6.64 (t, J¼7.5 Hz, 2H), 4.30 and 4.25 (dd, J¼13.0, 12.8 Hz, 4H), 3.99
and 3.95 (tt, J¼6.7, 6.7 Hz, 4H), 3.38 and 3.31 (dd, J¼13.1, 13.0 Hz,
4H), 2.09–2.01 (m, 4H), 1.72–1.65 (m, 4H), 1.48–1.26 (m, 16H), 0.89
(t, J¼6.8 Hz, 6H). 13C NMR:
d 153.3, 151.9, 151.3, 135.7, 133.4, 131.8,
129.0, 128.7, 128.5, 128.2, 127.2, 125.4, 119.1, 117.6, 77.2, 77.1, 77.0,
76.8, 76.7, 32.0, 31.9, 31.4, 31.3, 30.0, 29.9, 29.5, 29.4, 29.3, 29.2, 26.0,
25.9, 22.7, 14.1. Anal. Calcd for C44H55BrO4: C, 72.61; H, 7.62. Found:
C, 72.80; H, 7.67%.
3.6. 1,3-Alternate 5-bromo-26,28-di(octyloxy)calix[4]-
arene-25,27-benzocrown-6 (15)
3.8.1. 1,3-Alternate 5-(N-methanesulfonyl carbamoyl)-26,28-
di(octyloxy)calix[4]arene-25,27-benzocrown-6 (17)
To 13 (2.60 g, 3.58 mmol) in MeCN (500 mL) under nitrogen,
Cs2CO3 (4.67 g, 14.32 mmol) and ditosylate 14 (2.34 g, 3.93 mmol)
were added and the mixture was refluxed for 24 h. Then 10% HCl
(150 mL) was added and the MeCN was evaporated in vacuo. To the
aq residue CH2Cl2 (150 ml) was added. The organic layer was sep-
arated, washed twice with water, dried over MgSO4 and evaporated
in vacuo. The residue was chromatographed on silica gel with
hexanes/EtOAc (10:1) as eluent, yielding 3.20 g (91%) of 15 as an oil.
Chromatography on silica gel with CH2Cl2/MeOH (60:1) as elu-
ent provided an 82% yield of white solid with mp 205–207 ꢁC. IR:
3594 (N–H), 1691 (C]O) cmꢀ1. 1H NMR:
d 10.37 (s, 1H), 7.61 (s, 2H),
7.06–7.03 (m, 4H), 7.00 (s, 4H), 6.96 (d, J¼7.3 Hz, 2H), 6.81 (t,
J¼7.5 Hz, 2H), 6.52 (t, J¼7.5 Hz, 1H), 4.07–4.03 (m, 2H), 3.97–3.93
(m, 2H), 3.88–3.84 (m, 2H), 3.82 (d, J¼4.3 Hz, 4H), 3.74 (s, 4H), 3.72–
3.65 (m, 4H), 3.57–3.46 (m, 6H), 3.41–3.37 (m, 4H), 3.20 (s, 3H),
1.47–1.43 (m, 2H), 1.35–1.12 (m, 22H), 0.93 and 0.92 (tt, J¼7.0,
1H NMR:
d
7.19 (s, 2H), 7.06–6.94 (m, 10H), 6.77 (t, J¼7.4 Hz, 3H),
7.0 Hz, 6H). 13C NMR:
d 168.3, 161.5, 156.8, 156.2, 149.2, 134.7, 134.3,
6.67 (t, J¼7.4 Hz, 1H), 4.17 (t, J¼4.9 Hz, 4H), 3.84–3.74 (m, 8H), 3.70
(d, J¼8.4 Hz, 3H), 3.67–3.63 (m, 3H), 3.55–3.50 (m, 6H), 3.43–3.39
(m, 4H), 1.34–1.12 (m, 24H), 0.92 and 0.91 (tt, J¼7.0, 7.0 Hz, 6H). 13C
133.8, 132.7, 130.4, 130.3, 130.3, 129.5, 126.6, 122.5, 122.4, 122.1,
116.5, 77.3, 77.0, 76.8, 71.0, 70.8, 70.4, 70.1, 69.8, 69.6, 40.8, 37.8, 37.7,
31.9, 31.8, 29.9, 29.7, 29.6, 29.4, 29.3, 29.1, 25.8, 25.7, 22.7, 14.1. Anal.
Calcd for C60H77NO11S: C, 70.63; H, 7.61; N, 1.37. Found: C, 70.40; H,
7.68; N, 1.22%.
NMR:
d 156.7, 156.2, 156.1, 149.4, 136.5, 134.0, 133.8, 133.0, 132.2,
130.2, 129.8, 129.7, 122.4, 122.2, 121.9, 115.8, 114.4, 77.3, 77.0, 76.8,
71.0, 70.6, 70.5, 70.2, 70.1, 69.9, 37.8, 37.5, 31.9, 29.7, 29.5, 29.4, 29.4,
29.2, 25.8, 22.7, 14.1. Anal. Calcd for C58H73BrO8: C, 71.22; H, 7.52.
Found: C, 70.85; H, 7.34%.
3.8.2. 1,3-Alternate 5-(N-benzenesulfonyl carbamoyl)-26,28-
di(octyloxy)calix[4]arene-25,27-benzocrown-6 (18)
Chromatography on silica gel with CH2Cl2/MeOH (80:1) as elu-
ent gave a 75% yield of white solid with mp 162–164 ꢁC. IR: 3598
3.7. 1,3-Alternate 5-carboxy-26,28-di(octyloxy)calix[4]-
arene-25,27-benzocrown-6 (16)
(N–H), 1698 (C]O) cmꢀ1. 1H NMR:
d 11.39 (s, 1H), 8.12 and 8.10 (dd,
J¼1.1, 1.2 Hz, 2H), 7.47–7.44 (m, 3H), 7.25–7.22 (m, 2H), 7.04–6.95
(m, 9H), 6.76 (t, J¼7.5 Hz, 2H), 6.39 (t, J¼7.5 Hz, 1H), 4.07–4.03 (m,
2H), 3.99–3.95 (m, 2H), 3.83–3.80 (m, 2H), 3.74–3.65 (m, 13H), 3.60
(t, J¼7.5 Hz, 2H), 3.50–3.45 (m, 4H), 3.38–3.34 (m, 2H), 1.61–1.56
(m, 2H), 1.44–1.43 (m, 2H), 1.37–1.21 (m, 20H), 0.94–0.90 (m, 6H).
To a stirred solution of 14 (3.00 g, 3.07 mmol) in THF (250 mL)
under nitrogen at ꢀ75 ꢁC, 0.6 M BuLi (0.79 g, 12.28 mmol) in hex-
ane was added, which caused the colorless solution to turn red.
After 20 min at ꢀ75 ꢁC, CO2 was bubbled through the solution for
30 min during which time the red color disappeared. After another
15 min at ꢀ75 ꢁC, the mixture was allowed to warm to room
temperature and was quenched by careful addition of water. The
solvent was evaporated in vacuo and CH2Cl2 was added to the
residue. The organic layer was washed with 1 N HCl then water,
dried over MgSO4 and evaporated in vacuo. The residue was
recrystallized from CH2Cl2/MeOH to yield 1.80 g (62%) of 16 with
13C NMR:
d 167.9, 161.3, 156.6, 156.0, 148.5, 139.6, 134.5, 133.8, 133.7,
132.9, 132.6, 130.9, 130.7, 130.4, 129.9, 128.6, 128.3, 127.4, 122.3,
122.1, 121.7, 113.8, 77.3, 77.0, 76.8, 71.8, 71.6, 71.1, 69.9, 69.5, 68.4,
37.3, 31.9, 30.1, 29.7, 29.7, 29.4, 29.4, 25.9, 25.8, 22.7, 14.1. Anal. Calcd
for C65H79NO11S: C, 72.13; H, 7.36; N, 1.29. Found: C, 71.99; H, 7.17;
N, 1.24%.
mp 82–86 ꢁC. IR: 3220–2620 (O–H), 1698 (C]O) cmꢀ1
.
1H NMR:
3.8.3. 1,3-Alternate 5-(N-4-nitrobenzenesulfonyl carbamoyl)-
26,28-di(octyloxy)calix[4]-arene-25,27-benzocrown-6 (19)
Chromatography on silica gel with CH2Cl2/MeOH (100:1) as
eluent produced a 50% yield of yellow solid with mp 84–86 ꢁC.
d
7.74 (s, 2H), 7.03–6.91 (m, 10H), 6.78 (t, J¼7.5 Hz, 2H), 6.52 (t,
J¼7.5 Hz, 1H), 4.19–4.09 (m, 4H), 3.87–3.84 (m, 2H), 3.77–3.66 (m,
14H), 3.55–3.49 (m, 4H), 3.41–3.35 (m, 4H), 1.42–1.13 (m, 24H), 0.93
and 0.92 (tt, J¼7.0, 7.1 Hz, 6H). 13C NMR:
d
170.2, 160.3, 156.6, 155.9,
IR: 3598 (N–H), 1699 (C]O) cmꢀ1. 1H NMR:
d 11.61 (s, 1H), 8.30–
148.6,134.1,133.9,133.7,133.5,132.1,130.2, 130.0, 122.4,122.2,121.7,
114.4, 96.1, 77.2, 77.0, 76.8, 71.1, 70.6, 70.5, 70.2, 69.1, 37.7, 37.7, 31.9,
8.28 (m, 2H), 7.97–7.94 (m, 2H), 7.49 (s, 2H), 7.06–7.03 (m, 6H),
7.00–6.97 (m, 2H), 6.94 (d, J¼7.6 Hz, 2H), 6.77 (t, J¼7.5 Hz, 2H),

M. Surowiec et al. / Tetrahedron 65 (2009) 7777–7783
7783
6.39 (t, J¼7.5 Hz, 1H), 3.95–3.92 (m, 4H), 3.80–3.77 (m, 2H), 3.75–
3.60 (m, 14H), 3.56–3.51 (m, 4H), 3.47 (t, J¼7.6 Hz, 2H), 3.33 and
of the calixcrown in CHCl3 (2.0 mL) were vortexed for 15 min. After
centrifuging for 10 min to insure phase separation, a 0.50-mL
sample of the aqueous phase was removed and diluted to 10.0 mL
with deionized water. The pH of the extracted aqueous phase was
measured and the residual concentration of Agþ in the diluted
aqueous phase was determined by atomic absorption
spectrophotometry.
3.31 (tt, J¼4.8, 5.0 Hz, 2H), 1.62–1.56 (m, 2H), 1.43–1.20 (m, 22H),
13
0.94–0.90 (m, 6H).
NMR: d 168.0, 161.6, 156.7, 156.0, 150.0,
148.3, 145.1, 134.7, 134.0, 133.6, 132.4, 130.9, 130.7, 130.7, 130.0,
129.7, 126.8, 123.4, 122.2, 122.1, 122.0, 114.2, 77.2, 77.0, 76.7, 71.8,
71.6, 71.0, 69.7, 69.5, 68.4, 37.3, 37.3, 31.9, 31.8, 30.1, 29.7, 29.5,
29.4, 29.3, 25.8, 25.8, 22.7, 14.1. Anal. Calcd for
C65H78N2O13S$1.3CH2Cl2: C, 64.33; H, 6.59; N, 2.26. Found: C,
64.36; H, 6.26; N, 2.09%.
Acknowledgements
3.8.4. 1,3-Alternate 5-(N-trifluoromethanesulfonyl carbamoyl)-
26,28-di(octyloxy)calix[4]-arene-25,27-benzocrown-6 (20)
Chromatography on silica gel with CH2Cl2/MeOH (70:1) as eluent
gave a 71% yield of white solid with mp 217–220 ꢁC. IR: 3583 (N–H),
This research was supported at TTU by the Office of Biological
and Environmental Research of the U.S. Department of Energy
(Grant Number FG02-03ER63676). This research was supported at
ORNL by the Environmental Management Science Program of the
Offices of Science and Environmental Management of the U.S. De-
partment of Energy (Contract Number DE-AC05-00OR22725).
1725 (C]O) cmꢀ1.1H NMR:
d
7.56 (s, 2H), 7.06 (d, J¼7.6 Hz, 4H), 7.00–
6.99 (m, 6H), 6.81 (t, J¼7.5 Hz, 2H), 6.47 (t, J¼7.5 Hz, 1H), 4.10–4.09
(m, 4H), 3.79–3.73 (m, 14H), 3.65–3.57 (m, 6H), 3.47–3.43 (m, 4H),
1.53–1.49 (m, 2H),1.38–1.17 (m, 22H), 0.94 and 0.93 (tt, J¼7.0, 7.0 Hz,
6H). 13C NMR:
d 166.8, 162.1, 156.6, 156.0, 148.6, 135.0, 133.9, 133.8,
Supplementary data
132.4, 131.0, 130.7, 130.0, 126.4, 122.4, 122.2, 121.7, 114.0, 84.3, 77.3,
77.0, 76.8, 71.7, 71.6, 71.1, 70.1, 69.7, 68.7, 37.4, 31.9, 30.1, 29.7, 29.6,
29.4, 29.4, 25.9, 25.8, 22.7, 14.1. Anal. Calcd for C60H74F3NO11S: C,
67.08; H, 6.94; N, 1.30. Found: C, 66.94; H, 6.94; N, 1.38%.
Supplementary data associated with this article can be found in
online version, at doi:10.1016/j.tet.2009.07.006.
3.9. Solid-state structure determination for ligand 17
References and notes
1. Asfari, Z.; Wagner, S.; Vicens, J. J. Inclusion Phenom. Macrocyclic Chem. 1994, 19,
137.
2. Casnati, A.; Ungaro, R.; Asfari, Z.; Vicens, J. In Calixarenes 2001; Asfari, A.,
Bo¨hmer, V., Harrowfield, J., Vicens, J., Eds.; Kluwer Academic: Dordrecht, The
Netherlands, 2001; pp 356–384.
Single crystals were obtained by slow evaporation of a CHCl3/
EtOH solution of 17. Single-crystal X-ray data were collected on
a Bruker SMART APEX CCD diffractometer with fine-focus MoK
radiation (
a
l
¼0.71073 Å), operated at 50 kV and 30 mA. The struc-
ture was solved by direct methods and refined on F2 using the
SHELXTL software package.19 Absorption corrections were applied
using SADABS, part of the SHELXTL package. All non-hydrogen
atoms were refined anisotropically. Hydrogen atoms were placed in
idealized positions and refined with a riding model.
3. Gutsche, C. D. Calixarenes. An Introduction, 2nd ed.; Royal Society of Chemistry:
Cambridge, UK, 2008; pp 104–107.
4. Silorinne, K.; Nissinen, M. J. Inclusion Phenom. Macrocyclic Chem. 2008, 61, 11.
5. Sliwa, S.; Kozlowski, C. Calixarenes and Resorcinarenes. Synthesis, Properties and
Applications; Wiley-VCH: Weinheim, Germany, 2009; pp 165–174.
6. Kim, J. S.; Vicens, J. J. Inclusion Phenom. Macrocyclic Chem. 2009, 63, 189.
7. Casnati, A.; Pochini, A.; Ungaro, R.; Ugozzoli, F.; Arnaud, F.; Fanni, S.; Schwing,
M.-J.; Egberink, R. J. M.; de Jong, F.; Reinhoudt, D. N. J. Am. Chem. Soc. 1995, 117,
2767.
8. Casnati, A.; Pochini, A.; Ungaro, R.; Bocchi, C.; Ugozzoli, F.; Egberink, R. J. M.;
Struijk, H.; Lugternerg, R.; de Jong, F.; Reinhoudt, D. N. Chem. Eur. J. 1996, 2, 436.
9. Sachleben, R. A.; Bonnesen, P. V.; Descazeud, T.; Haverlock, J.; Urvoas, A.; Moyer,
B. A. Solvent Extr. Ion Exch. 1999, 17, 1445.
10. Talanov, V. S.; Talanova, G. G.; Bartsch, R. A. Tetrahedron Lett. 2000, 41, 8221.
11. Talanov, V. S.; Talanova, G. G.; Gorbunova, M. G.; Bartsch, R. A. Tetrahedron Lett.
2002, 43, 1929.
12. Talanov, V. S.; Talanova, G. G.; Gorbunova, M. G.; Bartsch, R. A. J. Chem. Soc.,
Perkin Trans. 2 2002, 209.
13. Talanova, G. G.; Talanov, V. S.; Hwang, H.-S.; Eliasi, B. A.; Bartsch, R. A. J. Chem.
Soc., Perkin Trans. 2 2002, 1869.
14. Thuery, P.; Nierlich, M.; Arnaud-Neu, F.; Souley, B.; Asfari, Z.; Vicens, J. Supramol.
Chem. 1999, 11, 143.
15. Gorbunova, M. G.; Bonnesen, P. V.; Engle, N. L.; Bazelair, E.; Delmau, L. H.;
Moyer, B. A. Tetrahedron Lett. 2003, 44, 5397.
16. Gutsche, C. D.; Lin, L.-G. Tetrahedron 1986, 42, 1633.
17. Casnati, A.; Fochi, M.; Minari, P.; Pochini, A.; Reggiani, M.; Ungaro, R.; Rein-
houdt, D. N. Gazz. Chim. Ital. 1996, 126, 99.
Crystal
data
for
17:
C60H77NO11S,
M¼1020.29,
0.41ꢄ0.29ꢄ0.22 mm3, triclinic, space group P-1 (No. 2), a¼
13.6541(15), b¼14.2125(15), c¼15.6432(17) Å,
a
¼96.567(2),
b
¼104.916(2),
g
¼106.054(2)ꢁ,
V¼2762.2(5) Å3,
Z¼2,
Dc¼1.227 g/cm3, F000¼1096, MoK
a
radiation,
l¼0.71073 Å,
T¼173(2) K,
2
qmax¼56.7ꢁ, 34,638 reflections collected, 13,683
unique (Rint¼0.0233). Final GOF¼1.192, R1¼0.0723, wR2¼0.1640, R
indices based on 12,273 reflections with I>2s
(I) (refinement on F2),
661 parameters, 0 restraints. Lp and absorption corrections applied,
m
¼0.119 mmꢀ1
.
Crystal data for 17 have been deposited with the Cambridge
Crystallographic Data Centre under reference CCDC 727689.
3.10. Solvent extraction of AgD
A 1.0 mM aqueous AgNO3 solution (2.0 mL, pH adjusted with
HNO3 or tetramethylammonium hydroxide) and a 1.0 mM solution
18. Huber, V. J.; Ivy, S. N.; Lu, J.; Bartsch, R. A. Chem. Commun. 1997, 1499.
19. SHELXTL 6.12; Bruker AXS: Madison, WI, 1997.