Synthesis of lipophilic lariat ethers with pendant N-(X)sulfonyl carboxamide groups

Article abstract of DOI:10.1002/jhet.5570410412

Synthetic routes to sixteen lipophilic lariat ether N-(X)sulfonyl carboxamides with X = trifluoromethyl, methyl, phenyl, and p-nitrophenyl are described. For this new family of proton-ionizable lariat ethers in which the acidity can be 'tuned' by X group variation, the ring size is systematically varied from 12-crown-4 to 14-crown-4 to 15-crown-5 to 18-crown-6.

Full text of DOI:10.1002/jhet.5570410412

Jul-Aug 2004
557
Synthesis of Lipophilic Lariat Ethers with Pendant N-(X)sulfonyl
Carboxamide Groups
Hui Hu and Richard A. Bartsch*
Department of Chemistry and Biochemistry, Texas Tech University,
Lubbock, Texas 79409-1061
Received December 29, 2003
Synthetic routes to sixteen lipophilic lariat ether N-(X)sulfonyl carboxamides with X = trifluoromethyl,
methyl, phenyl, and p-nitrophenyl are described. For this new family of proton-ionizable lariat ethers in
which the acidity can be 'tuned' by X group variation, the ring size is systematically varied from 12-crown-4
to 14-crown-4 to 15-crown-5 to 18-crown-6.
J. Heterocyclic Chem., 41, 557 (2004).
Crown ethers with a pendant proton-ionizable group are
four oxygen atoms, attachment to the lipophilic, proton-
efficient reagents for the solvent extraction of alkali metal
cations and their transport across bulk liquid, liquid surfac-
tant (emulsion), polymer-supported, and polymer inclu-
sion membranes [1-4]. Compared with crown ether lig-
ands that do not possess acidic functions, such proton-ion-
izable lariat [5] ethers have the distinct advantage that
transfer of the metal cation from the aqueous phase into the
organic medium does not require concomitant transport of
an aqueous phase anion [6]. This factor is of immense
importance for potential practical separation processes in
which hard, hydrophilic, aqueous-phase anions, such as
chloride, nitrate and sulfate, would be involved.
Previously we have reported the synthesis of lipophilic
crown ethers with a pendant carboxylic acid group or
phosphonic acid monoethyl ester group, 1 and 2, respec-
tively [7,8]. The selectivity in competitive alkali metal
cation extractions by these ligands was found to be influ-
enced both by the size of the crown ether ring (CE) and the
identity of the acidic group [9,10]. To better assess the
a ffect of varying the acidic function, a closely related
series of lariat ether N-(X)sulfonyl carboxamides 3 has
now been prepared. By variation of the electronic proper-
ties of X, the acidity of the proton-ionizable group can be
altered [11,12].
ionizable moiety is via a carbon atom in a shorter bridge.)
Crown Ether
Ring Size
Compound with X =
CF
CH
C H
p-NO C H
2 6 4
3
3
6
5
12-crown-4
14-crown-4
15-crown-5
18-crown-6
4
8
12
16
5
9
13
17
6
10
14
18
7
11
15
19
With a few exceptions, the precursor lipophilic lariat
ether carboxylic acids 1 with CE = 12-crown-4, 14-crown-
4, 15-crown-5, and 18-crown-6 were prepared by pub-
lished methods [6]. This general route (Scheme 1)
involves formation of the crown ether portion by a ring-
closure reaction to provide the (benzyloxymethyl)crown
ether 20 , followed by hydrogenolysis to produce the
(hydroxymethyl)crown ether 2 1, and preparation of the
(tosyloxymethyl)crown ether 22. Reaction of methyl
5-decylsalicylate with sodium or potassium hydride and
Results and Discussion.
the (tosyloxymethyl)crown ether 22 gave the correspond-
ing
lariat ether ester 23 that was hydrolyzed to form the
lariat
For the new family of lipophilic, proton-ionizable lariat
ethers 3, the crown ether ring size is varied from 12-
crown-4 (12C4) to 14-crown-4 (14C4) to 15-crown-5
(15C5) to 18-crown-6 (18C6) and the X group is changed
from trifluoromethyl to methyl to phenyl to p-nitrophenyl
in compounds 4-19. (For the 14-crown-4 rings with alter-
nating three-carbon and two-carbon bridges connecting the
ether carboxylic acid 1. Although the use of sodium
hydride provided 58-72% yields of the coupling product
when the crown ether ring in 22 was 12-crown-4, 14-
crown-4, and 18-crown-6, the yield for a 15-crown-5 ring
size was only 35%. Changing to potassium hydride pro-
vided a markedly increased 63% yield of 23 with CE = 15-

558
H. Hu and R. A. Bartsch
Vol. 41
crown-5. The lower yield of this coupling product
obtained with sodium hydride as the base is attributed to
strong interaction of the metal cation within the cavity of
the crown ether of the lariat ether alkoxide. Ion pairing of
the cavity-complexed metal ion with the alkoxide center
deactivates the nucleophile, leading to diminished yield.
With potassium hydride as the base, there a mismatch in
the sizes of the potassium cation and the 15-crown-5 cav-
ity, so strong ion pairing does not take place. To test this
supposition, the reaction of methyl 5-decylsalicylate and
hydroxymethyl-18-crown-6 was performed with potas-
sium hydride as the base. In this case, there is a match
between the crown ether cavity and the yield of coupling
product should decrease compared to an analogous reac-
tion with sodium hydride as the base. In agreement, the
yield of 23 with CE = 18-crown-6 dropped to 22% with
potassium hydride as the base, compared with 72% when
sodium hydride was employed.
In the current research, it was found that the yield of
(benzyloxymethyl)-15-crown-5 (24) from cyclization of 3-
(benzyloxy)propane-1,2-diol [13,14] and tetraethylene
glycol ditosylate was improved from 39% with sodium
hydride in dimethylformamide-tetrahydrofuran [15] or
23% with potassium tert-butoxide in tetrahydrofuran [16]
to 67% when sodium hydroxide in aqueous tetrahydrofu-
ran was utilized (Scheme 2).
For the synthesis of (benzyloxymethyl)-18-crown-6 (27)
(Scheme 3), the precursor diol 4-benzyloxymethyl-3,6-
dioxa-1,8-octanediol (2 6) was prepared in 85% yield by
direct reduction of dicarboxylic acid 25 with lithium
Scheme 1
Scheme 2
Scheme 3

Jul-Aug 2004
Synthesis of Lipophilic Lariat Ethers with Pendant N-(X)sulfonyl Carboxamide Groups
559
Melting points were determined with a Mel-Temp melting
point apparatus. Infrared (ir) spectra were recorded with a
Perkin-Elmer Model 1600 FT-IR spectrophotometer. Proton
nuclear magnetic resonance (nmr) spectra were obtained with a
Bruker AF-300 (300 MHz) spectrometer. Carbon nuclear mag-
netic resonance (nmr) spectra were obtained with a Varian Unity
INOVA spectrometer at 126 MHz. Combustion analysis was per-
formed by Desert Analytics Laboratory of Tucson, Arizona.
aluminum hydride in tetrahydrofuran rather than the reported
esterification of 25 followed by reduction with lithium alu-
minum hydride [17]. Reaction of diol 26, the ditosylate of
triethylene glycol, and potassium t e rt-butoxide in tetrahydro-
furan gave a 73% yield of 2 7, which is a considerable
improvement over the 54% yield when the cyclization was
promoted by potassium hydride in tetrahydrofuran [18].
The lipophilic lariat ether carboxylic acids 1 were con-
verted into the corresponding lariat ether acid chlorides by
treatment with oxalyl chloride in benzene (Scheme 4).
Subsequently the acid chlorides were reacted with sodium
hydride and commercially available trifluoromethanesul-
fonamide, methanesulfonamide, benzenesulfonamide, or
p-nitrobenzene sulfonamide in tetrahydrofuran to give the
lipophilic lariat ether N-(X)sulfonyl carboxamides 3
(Scheme 4).
(Benzyloxymethyl)-15-crown-5 (24).
To 3-(benzyloxymethyl)-1,2-diol (4.00 g, 22 mmol) in 40 ml
of tetrahydrofuran-water (40:1) was added sodium hydroxide
(2.20 g, 55 mmol). The reaction mixture was stirred and gently
heated under nitrogen at 60 °C until the base dissolved com-
pletely after which a solution of the ditosylate of tetraethylene
glycol (11.00 g, 22 mmol) in 20 ml of tetrahydrofuran was added
dropwise. The mixture was stirred and heated overnight. An
additional amount (2.20 g) of ditosylate was added in one portion
Scheme 4
and stirring and heating were continued for an additional 10 h.
After cooling to room temperature, the reaction mixture was fil-
tered and the filtrate was evaporated in vacuo. The residue was
chromatographed on alumina with dichloromethane then
dichloromethane-ethyl acetate as eluents to give 5.04 g (67%) of
colorless oil. IR (neat): 1127 and 1028 (C-O) cm . H NMR
(deuteriochloroform): δ 3.64-3.66 (m, 21H), 4.55 (s, 2H), 7.32
(m, 5H).
The new lipophilic lariat ether N-(X)sulfonyl carbox-
amides 4-19 were characterized by proton magnetic reso-
nance spectroscopy, infrared spectroscopy, and combus-
tion analysis. Carbon nuclear magnetic resonance spec-
tra were obtained for N-(trifluoromethyl)sulfonyl carbox-
amides 4, 8, 12, and 16 with different ring sizes and N-
(X)sulfonyl carboxamide compounds with four different
X groups, but a common 15-crown-5 ring. In the proton
magnetic resonance spectra of the proton-ionizable lariat
ethers with a given ring size, the chemical shift for the
N-H proton uniformly decreased as X was varied X = tri-
fluoromethyl > p-nitrophenyl > phenyl > methyl, indicat-
ing decreasing acidity in this order. This is consistent
with the effect of pH of the aqueous phase upon eff i-
ciency of alkali metal cation extraction into chloroform
observed in the solvent extraction studies performed with
these ligands [19].
-1
1
(Benzyloxymethyl)-18-crown-6 (27).
To a solution of diol 26 (13.50 g, 50 mmol) in tetrahydrofuran
(480 ml) was added under nitrogen potassium t-butoxide (12.20
g, 110 mmol). The mixture was stirred at room temperature for 1
h and a solution of the ditosylate of triethylene glycol (25.19 g,
55 mmol) in tetrahydrofuran (95 ml) was added dropwise over a
1 h-period. The reaction mixture was stirred at room temperature
for 2 days and then refluxed for an additional 3 days. The solvent
was evaporated in vacuo and the residue was chromatographed
on alumina with dichloromethane as eluent to produce 27 as a
-1
pale yellow oil (14.07 g, 73 % yield). IR (neat): 1115 (C-O) cm .
1
H NMR (deuteriochloroform): δ 3.50-3.80 (m, 25H), 4.51 (s,
2H), 7.23-7.31 (m, 5H).
EXPERIMENTAL
General Procedure for the Preparation of 5-(Decyl)-2-
[(methoxymethyl)crown ether]benzoyl Chlorides 28-31.
Reagents and solvents were purchased from commercial
sources and used without further purification unless otherwise
noted. Tetrahydrofuran was dried and purified by distillation
from sodium under nitrogen with benzophenone ketyl as
indicator.
To the dry lipophilic lariat ether carboxylic acid (0.50 g) in 75
mL of benzene under nitrogen was added oxalyl chloride (0.64
ml). The reaction mixture was stirred and refluxed for 6 h. The

560
H. Hu and R. A. Bartsch
Vol. 41
excess oxalyl chloride and benzene were evaporated in vacuo to
produce a quantitative yield of the lipophilic lariat ether acid
chloride, which was used without purification in the next step.
6.96 (d, 1H, J = 8.6 Hz), 7.36 (dd, 1H), 7.93,7.94 (d, 1H, J = 2.3
13
Hz), 10.98 (s, 1H). C NMR (deuteriochloroform): _14.1, 22.7,
29.1, 29.3, 29.4, 29.5, 29.6, 31.3, 31.9, 34,7, 68.9, 69.4, 69.8,
70.3, 71.7, 113.1, 118.1, 120.6, 132.5, 136.0, 137.0, 155.4, 162.2.
5-(Decyl)-2-(methoxymethyl-12-crown-4)benzoyl Chloride (28).
Anal. Calcd for C
Found: C, 54.10; H, 7.15; N, 2.48.
H F NO S: C, 54.26; H, 7.08; N, 2.34.
27 42 3 8
This compound was obtained as a beige oil. IR (neat): 1779
-1
(C=O), 1139 and 1025 (C-O) cm . H NMR (CDCl ): δ 0.88 (t,
1
3
N-Methylsulfonyl 5-(Decyl)-2-(methoxymethyl-12-crown-
4)benzamide (5).
3H), 1.26 (m, 16H), 2.59 (t, 2H), 3.70-4.05 (m, 17H), 6.94-6.98
(d, 1H), 7.27 (dd, 1H), 7.97,7.98 (d, 1H).
This compound was produced in 44% yield as a white solid
with mp 64-65 °C. IR (deposit from deuteriochloroform solution
onto a sodium chloride plate): 1686 (C=O), 1342 (S=O), 1244
and 1135 (C-O) cm . H NMR (deuteriochloroform): δ 0.88 (t,
3H, J = 6.1 Hz), 1.25 (m, 16H), 2.58 (t, 2H, J = 7.8 Hz), 3.39 (s,
3H), 3.68-4.27 (m, 17H), 6.94 (d, 1H, J = 8.5 Hz), 7.26 (dd, 1H),
7.95,7.97 (d, 1H, J = 2.3 Hz), 10.52 (s, 1H).
5-(Decyl)-2-(methoxymethyl-14-crown-4)benzoyl Chloride (29).
This compound was produced as a beige oil. IR (neat): 1782
-1
1
(C=O), 1128 and 1032 (C-O) cm . H NMR (deuteriochloro-
form): δ 0.88 (t, 3H), 1.26 (m, 16H), 1.80-1.82 (m, 4H), 2.59 (t,
2H), 3.63-4.06 (m, 17H), 6.90-6.92 (d, 1H), 7.36 (dd, 1H),
7.83,7.84 (d, 1H, J = 2.2 Hz).
-1
1
Anal. Calcd for C
Found: C, 59.88; H, 8.15; N, 2.65.
H NO S: C, 59.64; H, 8.34; N, 2.58.
27 45 8
5-(Decyl)-2-(methoxymethyl-15-crown-5)benzoyl Chloride (30).
This compound was obtained as a beige oil. IR (neat): 1780
-1
1
(C=O), 1137 and 1027 (C-O) cm . H NMR (deuteriochloro-
form): δ 0.88 (t, 3H, J = 6.2 Hz), 1.26 (m, 16H), 2.59 (t, 2H),
3.64-3.94 (m, 21H), 6.89 (d, 1H), 7.36 (dd, 1H), 7.85,7.86 (d, 1H,
J = 2.1 Hz).
N-Phenylsulfonyl 5-(Decyl)-2-(methoxymethyl-12-crown-
4)benzamide (6).
This compound was isolated in 95% yield as a pale yellow oil.
IR (neat): 1691 (C=O), 1349 and 1187 (S=O), 1243 and 1135 (C-
-1
O) cm . H NMR (CDCl ): δ 0.84-0.90 (t, 3H), 1.23 (m, 16H),
1
5-(Decyl)-2-(methoxymethyl-18-crown-6)benzoyl Chloride (31).
3
2.48-2.52 (t, 2H), 3.68-4.27 (m, 17H), 6.90 (d, 1H, J = 8.5 Hz),
7.26 (dd, 1H), 7.55-7.59 (m, 3H), 7.84,7.85 (d, 1H, J = 2.4 Hz),
8.12-8.17 (m, 2H), 10.70 (s, 1H).
A n a l. Calcd for C H NO S: C, 63.45; H, 7.82; N, 2.31.
32 47 8
Found: C, 63.80; H, 7.97; N, 2.39.
This compound was produced as a beige oil. IR (neat): 1778
-1
1
(C=O), 1118 and 1027 (C-O) cm . H NMR (deuteriochloro-
form): δ 0.88 (t, 3H, J = 6.2 Hz), 1.26 (m, 16H), 2.59 (t, 2H, J =
7.5 Hz), 3.68-4.12 (m, 25H), 6.95 (d, 1H), 7.31-7.36 (m, 1H),
7.85 (s, 1H).
N-(p-Nitrophenyl)sulfonyl 5-(Decyl)-2-(methoxymethyl-12-
crown-4)benzamide (7).
General Procedure for the Preparation of N-(X)sulfonyl 5-
(Decyl)-2-(methoxymethylcrown ether)benzamides 4-19.
This compound was obtained in 90 %yield as a pale yellow oil.
IR (neat): 1693 (C=O), 1350 and 1186 (S=O), 1245 and 1137 (C-
O) cm . H NMR (deuteriochloroform): δ 0.87 (t, 3H, J = 6.1
Hz), 1.23 (m, 16H), 2.58 (t, 2H, J = 7.9 Hz), 3.71-4.25 (m, 17H),
6.91 (d, 1H, J = 8.5 Hz), 7.27 (dd, 1H), 7.79,7.81 (d, 1H, J = 2.3
Hz), 8.37 (m, 4H), 10.87 (s, 1H).
Under nitrogen, sodium hydride (95%, 0.11 g, 4.6 mmol, 5.0
eq) was added to 15 ml of tetrahydrofuran. A solution of the
appropriate sulfonamide (1.2 eq) in 30 ml of tetrahydrofuran was
added over a 10-min period and the mixture was stirred at room
temperature for 1.5 h. A solution of the lariat ether acid chloride
(1.0 eq) in 45 ml of tetrahydrofuran was added over a 10-min
period and the mixture was stirred overnight at room temperature.
The mixture was cooled to 0 °C and 30 ml of ice-water was care-
fully added dropwise to destroy the unreacted sodium hydride.
The tetrahydrofuran was evaporated in vacuo. The residue was
dissolved in 40 ml of water. The alkaline aqueous solution was
extracted with dichloromethane (100 ml, then 30 ml) and the com-
bined extracts were washed with 10 % aq. potassium carbonate (2
X 45 ml). The combined potassium carbonate washes were back
extracted with dichloromethane (2 X 30 ml) and the org a n i c
extracts were combined, dried over magnesium sulfate and evapo-
rated in vacuo. The residue was purified by chromatography on
alumina with methanol-dichlormethane (1:10) as eluent. The
resultant sodium salt was dissolved in dichloromethane (50 ml)
and protonated by shaking with 50 ml of 1 N hydrochloric acid.
The organic layer was separated, washed with water (2 X 50 ml),
dried over magnesium sulfate and evaporated in vacuo.
-1
1
Anal. Calcd for C
Found: C, 59.14; H, 7.28; N, 4.18.
H N O S: C, 59.06; H, 7.12; N, 4.30.
32 46 2 10
N- ( Trifluoromethyl)sulfonyl 5-(Decyl)-2-(methoxymethyl-14-
crown-4)benzamide (8).
This compound was realized in 84%yield as a colorless oil. IR
(neat): 1717 (C=O), 1375 and 1202 (S=O), 1288 and 1131 (C-O)
-1
1
cm . H NMR (deuteriochloroform): δ 0.88 (t, 3H, J = 6.2 Hz),
1.25 (m, 16H), 1.78-1.85 (m, 4H), 2.59 (t, 2H, J = 7.3 Hz), 3.48-
3.95 (m, 15H), 4.26,4.28 (d, 2H, J = 5.0 Hz), 6.96 (d, 1H, J = 8.5
Hz), 7.36-7.42 (dd, 1H), 7.94,7.96 (d, 1H, J = 2.3 Hz), 10.87 (s,
13
1H). C NMR (deuteriochloroform): δ 14.1, 22.7, 29.1, 29.3,
29.4, 29.5, 29.6, 30.1, 30.3, 31.3, 31.9, 34.7, 65.3, 66.3, 67.6,
69.6, 70.1, 70.4, 70.4, 76.3, 112.8, 117.8, 118.0, 120.6, 132.6,
136.0, 137.0, 155.3, 162.0.
Anal. Calcd for C
Found: C, 55.37; H, 7.51; N, 2.24.
H F NO S: C, 55.66; H, 7.41; N, 2.24.
29 46 3 8
N- ( Trifluoromethyl)sulfonyl 5-(decyl)-2-(methoxymethyl-12-
crown-4)benzamide (4).
N-Methylsulfonyl 5-(Decyl)-2-(methoxymethyl-14-crown-
4)benzamide (9).
This compound was obtained in 94%yield as a pale yellow oil.
IR (neat): 1715 (C=O), 1372 and 1202 (S=O), 1289 and 1135 (C-
This compound was produced in 64% yield as a colorless oil. IR
1
-1
O) cm . H NMR (deuteriochloroform): δ 0.88 (t, 3H, J = 6.1
1
-1
(neat): 1724 (C=O), 1345 (S=O), 1246 and 1147 (C-O) cm .
H
NMR (CDCl ): δ 0.88 (t, 3H), 1.25 (m, 16H), 1.80-1.83 (m, 4H),
Hz), 1.26 (m, 16H), 2.58 (t, 2H, J = 7.9 Hz), 3.66-4.34 (m, 17H),
3

Jul-Aug 2004
Synthesis of Lipophilic Lariat Ethers with Pendant N-(X)sulfonyl Carboxamide Groups
561
2.59 (t, 2H), 3.39 (s, 3H), 3.62-3.70 (m, 15H), 4.22-4.25 (d, 2H),
6.93 (d, 1H, J = 8.5 Hz), 7.26 (dd, 1H), 7.96,7.98 (d, 1H, J = 2.3
Hz), 10.46 (s, 1H).
-1
1
cm . H NMR (deuteriochloroform): δ 0.87 (t, 3H, J = 6.1 Hz),
1.23 (m, 16H), 2.51 (t, 2H), 3.64-3.85 (m, 19H), 4.28 (m, 2H),
6.88-6.92 (d, 1H), 7.26 (dd, 1H), 7.53-7.58 (m, 3H), 7.83,7.84 (d,
13
Anal. Calcd for C
H NO S: C, 60.92; H, 8.64; N, 2.45.
1H, J = 2.3 Hz), 8.13-8.17 (m, 2H), 10.76 (s, 1H). C NMR
29 49 8
Found: C, 60.95; H, 8.84; N, 2.51.
(deuteriochloroform): δ 14.1, 22.7, 29.1, 29.3, 29.4, 29.5, 29.6,
31.3, 31.9, 34.7, 69.5, 69.7, 69.9, 70.4, 70.6, 70.7, 71.5, 71.6,
96.1, 112.8, 118.8, 128.5, 128.8, 132.1, 133.6, 134.9, 136.5,
139.9, 155.4, 162.9.
N-Phenylsulfonyl 5-(Decyl)-2-(methoxymethyl-14-crown-
4)benzamide (10).
This compound was isolated in 72% yield as a pale yellow oil.
IR (neat): 1714 (C=O), 1372 and 1202 (S=O), 1237 and 1130 (C-
Anal. Calcd for C
H NO S: C, 62.84; H, 7.91; N, 2.16.
34 51 9
Found: C, 63.03; H, 7.98; N, 2.28.
-1
1
O) cm . H NMR (deuteriochloroform): δ 0.87 (t, 3H), 1.23 (m,
16H), 1.82 (m, 4H), 2.51 (t, 2H), 3.66-3.75 (m, 15H), 4.22-4.24
(m, 2H), 6.90 (d, 1H), 7.26 (dd, 1H), 7.53-7.57 (m, 3H),
7.85,7.86 (d, 1H, J = 2.3 Hz), 8.13-8.17 (m, 2H), 10.62 (s, 1H).
N-(p-Nitrophenyl)sulfonyl 5-(Decyl)-2-(methoxy-15-crown-
5)benzamide (15).
This compound was obtained in 85% yield as a yellow oil. IR
(neat): 1690 (C=O), 1350 and 1186 (S=O), 1247 and 1131 (C-O)
Anal. Calcd for C H NO S: C, 64.43; H, 8.11; N, 2.21.
34 51 8
Found: C, 64.32; H, 8.13; N, 2.22.
-1
cm . H NMR (CDCl ): δ 0.87 (t, 3H), 1.23 (m, 16H), 2.48-2.52
1
3
(t, 2H), 3.65-4.25 (m, 21H), 6.94 (d, 1H), 7.27 (dd, 1H),
N-(p-Nitrophenyl)sulfonyl 5-(Decyl)-2-(methoxymethyl-14-
crown-4)benzamide (11).
13
7.78,7.79 (d, 1H, J = 2.3 Hz), 8.37 (m, 4H), 10.95 (s, 1H).
C
NMR (deuteriochloroform): δ 14.1, 22.7, 29.1, 29.3, 29.4, 29.5,
29.6, 31.3, 31.9, 34.7, 69.6, 69.7, 70.1, 70.3, 70.6, 70.6, 70.6,
70.7, 71.0, 71.7, 77.0, 113.0, 118.9, 128.5, 128.7, 132.0, 133.5,
134.8, 136.4, 139.4, 155.5, 163.0.
This compound was formed in 89% yield as a pale yellow solid
with a mp of 68-70 °C. IR (neat): 1691 (C=O), 1351 and 1186
-1
1
(S=O), 1243 and 1131 (C-O) cm . H NMR (deuteriochloro-
form): δ 0.87 (t, 3H), 1.23 (m, 16H), 1.84 (m, 4H), 2.48-2.52 (t,
2H), 3.67-3.78 (m, 15H), 4.25 (d, 2H, J = 5.1 Hz), 6.93 (d, 1H),
7.27 (dd, 1H), 7.81,7.82 (d, 1H, J = 2.3 Hz), 8.36-8.37 (m, 4H),
10.77 (s, 1H).
Anal. Calcd for C
H N O S: C, 58.77; H, 7.25; N, 4.03.
34 50 2 11
Found: C, 58.47; H, 7.43; N, 3.87.
N-(Trifluoromethyl)sulfonyl 5-(Decyl)-2-(methoxymethyl-18-
crown-6)benzamide (16).
Anal. Calcd for C
Found: C, 59.77; H, 7.32; N, 4.10.
H N O S: C, 60.16; H, 7.42; N, 4.13.
34 50 2 10
This compound was isolated in 29%yield as a colorless oil. IR
(neat): 1716 (C=O), 1370 and 1201 (S=O), 1290 and 1130 (C-O)
N-(Trifluoromethyl)sulfonyl 5-(Decyl)-2-(methoxymethyl-15-
crown-5)benzamide (12).
-1
1
cm . H NMR (deuteriochloroform): δ 0.88 (t, 3H, J = 6.5 Hz),
1.26-1.57 (m, 16H), 2.58 (t, 2H, J = 7.5 Hz), 3.58-4.48 (m, 24H),
4.49-4.51 (m, 1H), 6.99,7.01 (d, 1H, J = 8.6 Hz), 7.36-7.40 (dd,
This comound was obtained in 65% yield as a pale yellow oil.
IR (neat): 1715 (C=O), 1372 and 1202 (S=O), 1289 and 1130 (C-
13
1H), 7.91,7.92 (d, 1H, J = 2.3 Hz), 11.06 (s, 1H). C NMR (deu-
-1
1
O) cm . H NMR (deuteriochloroform): δ 0.88 (t, 3H, J = 6.1
Hz), 1.26-1.66 (m, 16H), 2.58 (t, 2H, J = 7.2 Hz), 3.57-4.26 (m,
21H), 4.37-4.42 (m, 1H), 6.97 (d, 1H, J = 8.5 Hz), 7.31-7.39 (dd,
teriochloroform): δ 14.1, 22.7, 29.1, 29.3, 29.4, 29.5, 29.6, 31.3,
31.9, 34.7, 69.1, 69.2, 69.4, 70.6, 70.6, 70.7, 70.7, 70.9, 71.6,
76.1, 109.9, 113.4, 118.1, 120.7, 132.3, 135.9, 136.8, 155.7,
162.3.
13
1H), 7.91,7.93 (d, 1H, J = 2.3 Hz), 11.06 (s, 1H). C NMR (deu-
teriochloroform): δ 14.1, 22.7, 29.1, 29.3, 29.4, 29.5, 29.6, 31.3,
31.9, 34.7, 69.0, 69.5, 69.7, 70.3, 70.5, 70.6, 70.6, 70.6, 70.9,
71.8, 76.5, 113.3, 118.2, 132.4, 135.9, 136.9, 155.6, 162.3.
Anal. Calcd for C H F NO S: C, 54.28; H, 7.22; N, 2.18.
29 46 3 9
Found: C, 54.12; H, 7.17; N, 2.26.
Anal. Calcd for C
Found: C, 54.04; H, 7.52; N, 2.25.
H F NO S: C, 54.29; H, 7.35; N, 2.04.
31 50 3 10
N-Methylsulfonyl 5-(Decyl)-2-(methoxy-18-crown-6)benzamide
(17).
This compound was realized in 86% yield as a colorless oil.
-1
IR (neat): 1686 (C=O), 1344 (S=O), 1247 and 1135 (C-O) cm .
H NMR (deuteriochloroform): δ 0.88 (t, 3H, J = 6.5 Hz), 1.26-
N-Methylsulfonyl 5-(Decyl)-2-(methoxymethyl-15-crown-
5)benzamide (13).
1
This compound was produced in 61% yield as a colorless oil.
-1
IR (neat): 1682 (C=O), 1344 (S=O), 1245 and 1134 (C-O) cm .
1.28 (m, 16H), 2.58 (t, 2H, J = 7.4 Hz), 3.39 (s, 3H), 3.62-3.88
(m, 23 H), 4.30 (m, 2H), 6.98 (d, 1H, J = 5.5 Hz), 7.26 (dd, 1H),
7.95,7.96 (d, 1H, J = 2.6 Hz), 10.56 (s, 1H).
1
H NMR (deuteriochloroform): δ 0.87 (t, 3H, J = 6.1 Hz), 1.25
(m, 16H), 2.58 (t, 2H, J = 8.0 Hz), 3.39 (s, 3H), 3.61-4.30 (m,
21H), 6.96 (d, 1H, J = 8.5 Hz), 7.26 (dd, 1H), 7.94,7.96 (d, 1H, J
Anal. Calcd for C
Found: C, 59.26; H, 8.70; N, 2.25.
H NO S: C, 58.93; H, 8.45; N, 2.22.
31 53 10
13
= 2.3 Hz), 10.58 (s, 1H). C NMR (deuteriochloroform): δ 14.1,
N-Phenylsulfonyl 5-(Decyl)-2-(methoxymethyl-18-crown-
6)benzamide (18).
22.7, 29.1, 29.3, 29.4, 29.5, 29.6, 31.3, 31.9, 34.8, 41.8, 69.5,
69.9, 70.3, 70.5, 70.6, 70.7, 71.0, 71.6, 76.9, 113.2, 118.9, 132.1,
135.1, 136.5, 155.6, 164.2.
This compound was obtained in 89% yield as a colorless oil.
IR (neat): 1690 (C=O), 1349 and 1187 (S=O), 1247 and 1120 (C-
A n a l. Calcd for C
H NO S: C, 59.26; H, 8.40; N, 2.38.
29 49 9
Found: C, 59.29; H, 8.36; N, 2.33.
-1
O) cm . H NMR (CDCl ): δ 0.87 (t, 3H, J = 6.0 Hz), 1.23 (m,
1
3
16H), 2.51 (t, 2H, J = 7.8 Hz), 3.64-3.95 (m, 23H), 4.31-4.34 (m,
2H), 6.93 (d, 1H, J = 8.5 Hz), 7.26 (dd, 1H), 7.53-7.58 (m, 3H),
7.83,7.84 (d, 1H, J = 2.2 Hz), 8.12-8.17 (m, 2H), 10.75 (s, 1H).
N-Phenylsulfonyl 5-(Decyl)-2-(methoxy-15-crown-5)benzamide
(14).
This compound was realized in 84% yield as a yellow oil. IR
(neat): 1693 (C=O), 1348 and 1187 (S=O), 1244 and 1133 (C-O)
Anal. Calcd for C
H NO S: C, 62.31; H, 7.99; N, 2.02.
36 55 10
Found: C, 62.33; H, 8.34; N, 2.11.

562
H. Hu and R. A. Bartsch
Vol. 41
Amiri-Eliasi, Solvent Extraction (Proceedings of the International
Solvent Extraction Symposia, June 21-27, 1998, Moscow, Russia), 1998,
pp. 205-214.
[5] G. W. Gokel and O. F. Schall, Comprehensive Supramolecular
Chemistry, Y. Inoue and G. W. Gokel, eds., Pergamon, New Your, 1996,
Vol. 1, pp 97-152.
N-(p-Nitrophenyl)sulfonyl 5-(Decyl)-2-(methoxymethyl-18-
crown-6)benzamide (19).
This compound was obtained in 92% yield as a pale yellow oil.
IR (neat): 1690 (C=O), 1351 and 1186 (S=O), 1248 and 1116 (C-
-1
O) cm . H NMR (CDCl ): δ 0.87 (t, 3H, J = 6.1 Hz), 1.23 (m,
1
3
16H), 2.48-2.52 (t, 2H), 3.63-3.95 (m, 23H), 4.35 (m, 2H), 6.94
(d, 1H), 7.27 (dd, 1H), 7.80 (d, 1H), 8.37 (m, 4H), 10.93 (s, 1H).
Anal. Calcd for C H N O S: C, 58.52; H, 7.37; N, 3.79.
36 54 2 12
Found: C, 58.57; H, 7.51; N, 3.76.
[6] J. Strzelbicki and R. A. Bartsch, Anal. Chem., 53, 2247
(1981).
[7] B. P. Czech, A. Czech, B. Son, H. K. Lee and R. A. Bartsch, J.
Heterocyclic Chem., 23, 465 (1986).
[8] B. P. Czech, D. H. Desi, J. Koszuk, A. Czech, D. A. Babb, T.
W. Robison and R. A. Bartsch, J. Heterocyclic Chem., 29, 867 (1992).
[9] W. Walkowiak, S. I. Kang, L. E. Stewart, G. N. Dip and R. A.
Bartsch, Anal. Chem., 62, 2022 (1990).
[10] W. Walkowiak, G. Ndip and R. A. Bartsch, Anal. Chem., 71,
1021 (1999).
[11] V. J. Huber, S. N. Ivy, J. Lu and R. A. Bartsch, J. Chem. Soc.,
Chem. Commun., 1499 (1997).
[12] R. A. Bartsch, S. N. Ivy, J. Lu, V. J. Huber, V. S. Talanov, W.
Walkowiak, C. Park and B. Amiri-Eliasi, Pure Appl. Chem., 70, 2293
(1998).
Acknowledgment.
This research was supported by the Chemical Sciences,
Geosciences, and Biosciences Division of the Office of Basic
Energy Sciences of the U.S. Department of Energy (Grant DE-
FG02-94ER14416 to RAB). We thank the National Science
Foundation for Grant CHE-9808436 that was used to purchase
the Varian Unity INOVA nmr spectrometer.
REFERENCES AND NOTES
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