reported earlier using a bulk liquid membrane apparatus.4,12
Two water phases (one containing the salt to be transported)
were separated by a dichloromethane phase which constituted
the membrane. The interior of the tube above the organic
medium was filled with the source phase which was 0.8 mL of
a solution of 0.1 M lithium, sodium, potassium, rubidium, and
caesium nitrate, respectively, using a single flux method. The
outer cylinder was filled with 5.0 mL of deionized water as the
receiving phase. The details of the transport conditions are
summarized in the footnotes of Table 1. Each experiment was
repeated three times in a room thermostated to 25 1 ЊC then
3 mL of the receiving phase was taken. The flux values (moles
transported sϪ1 m2) for the corresponding metal ion concen-
tration were determined by the use of a Perkin-Elmer 2380
atomic absorption spectrophotometer. Blank experiments for
which no calix[4]arene dibenzocrown ether was present were
performed to determine the membrane leakage.
3.17 (s, 6 H, CH3SO2OCH2CH2–). Anal. calcd for C24H34O12S2:
C, 49.82; H, 5.92. Found: C, 49.86; H, 5.81%.
General procedures for the synthesis of calix[4]arene
dibenzocrown ethers (3–8)
25,27-Dialkoxycalix[4]arene 14 (2.0 mmol) was dissolved in 50
mL of acetonitrile and added to an excess of Cs2CO3 (1.62 g,
5.0 mmol) and dibenzodimesylate (2.1 mmol) under nitrogen.
The reaction mixture was refluxed for 24 h. Then acetonitrile
was removed in vacuo and the residue extracted with 100 mL of
methylene chloride and 50 mL of 10% aqueous HCl solution.
The organic layer was separated and washed twice with water.
After the organic layer was separated and dried over anhydrous
magnesium sulfate followed by removing the solvent in vacuo
to give a brownish oil. Filtration column chromatography gave
3–8.
25,27-Bis(1-propyloxy)calix[4]arene dibenzocrown-6, 1,3-
alternate (3). Filtration column chromatography with ethyl
acetate–hexane = 1:6 as eluent provided pure 1,3-alternate
calix[4]arene dibenzocrown ethers as a white solid in over 90%
yield. Mp 229–232 ЊC. IR (KBr pellet, cmϪ1); 3068 (Ar-H),
1501, 1451, 1254, 1196. 1H NMR (CDCl3) δ 7.12–6.55 (m,
20 H, Ar-H), 4.37 (s, 4 H), 3.75 (s, 8 H, ArCH2Ar), 3.65–3.32
(m, 12 H), 1.25–1.16 (m, J = 7.4 Hz, 4 H, OCH2CH2CH3), 0.65
(t, J = 7.4 Hz, 6 H, OCH2CH2CH3). 13C NMR (CDCl3): δ 157.5,
156.7, 152.0, 149.7, 134.8, 134.7, 130.3, 129.9, 124.7, 123.3,
123.0, 122.8, 122.3, 115.9, 72.7, 71.0, 69.0, 68.0, 38.7, 23.3, 10.7.
FAB MS m/z (Mϩ) calcd 806.21, found 806.11. Anal. Calcd for
C52H54O8: C, 77.41; H, 6.69. Found: C, 77.30; H, 6.71%.
General procedures of dibenzodimesylate 13a–13d
Under nitrogen, to a solution of 13.2 mmol of 12 and 4.08 mL
(2.94 g, 29.0 mmol) of triethylamine in 100 mL of dry CH2Cl2
was added dropwise 2.14 mL (3.33 g, 29.0 mmol) of
methanesulfonyl chloride during a period of 30 min at 0 ЊC.
Upon complete addition, the reaction mixture was stirred for
5 h at 0 ЊC. Reaction temperature was slowly raised up to room
temperature and stirred for an additional 10 h. 50 mL of 10%
aqueous sodium bicarbonate solution was added and the
CH2Cl2 layer was separated. The organic layer was washed with
water (2 × 20 mL) and brine (2 × 20 mL) followed by drying
over anhydrous magnesium sulfate. Removal of CH2Cl2 in
vacuo provided a colorless oil which was recrystallized from 100
mL of diethyl ether to give the desired product.
25,27-Bis(1-propyloxy)calix[4]arene dibenzocrown-7, 1,3-
alternate (4). Recrystallized from the oil residue with 5:1
diethyl ether–hexanes: 90% yield; mp 178–181 ЊC; IR (KBr
1,2-Bis[2-(2-methylsulfonyloxyethyloxy)phenoxy]ethane
(13a). Removal of CH2Cl2 in vacuo provided a colorless oil
which was recrystallized from 100 mL of diethyl ether to
give 5.82 g (90%) of the desired product. Mp 158–160 ЊC. IR
(KBr pellet, cmϪ1) 1597, 1516, 1350 (SO2), 1181 (SO2). 1H
NMR (CDCl3) δ 7.14–6.90 (m, 8 H, Ar-H), 4.50 (s, 4 H,
–CH2CH2O–), 4.32 (s, 4 H, –CH2CH2O–), 4.25 (t, 4 H), 3.09 (s,
6 H, CH3SO2O–); FAB MS m/z (Mϩ) calcd 490.55, found
490.23. Anal. calcd for C22H26O10S2: C, 48.97; H, 5.34. Found:
C, 48.90; H, 5.21%.
1
pellet, cmϪ1); 3068 (Ar-H), 1501, 1451, 1254, 1196; H NMR
(CDCl3) δ 7.02–6.87 (m, 16 H), 6.78–6.70 (m, 4 H), 4.22 (t,
J = 5.1 Hz, 4 H), 4.08 (t, J = 5.1 Hz, 4 H), 3.89 (t, J = 5.1 Hz,
4 H), 3.76 (t, J = 5.1 Hz, 4 H), 3.70 (s, 8 H, ArCH2Ar), 3.41 (t,
J = 7.4 Hz, 4 H, OCH2CH2CH3), 1.47–1.38 (m, J = 7.4 Hz, 4 H,
OCH2CH2CH3), 0.77 (t, J = 7.4 Hz, 6 H, OCH2CH2CH3); 13C
NMR (CDCl3) δ 157.4, 156.8, 150.7, 149.8, 134.4, 134.3, 130.6,
130.5, 123.1, 122.8, 122.6, 122.3, 118.3, 116.1, 73.4, 71.1, 70.6,
69.8, 38.1, 23.7, 10.8; FAB MS m/z (Mϩ) calcd 850.31, found
850.30. Anal. calcd for C54H58O9: C, 76.20; H, 6.82. Found: C,
76.18; H, 6.87%.
1,5-Bis[2-(2-methylsulfonyloxyethyloxy)phenoxy]-3-oxa-
pentane (13b). 6.20 g (92%) of the desired product, a white
solid, was obtained. Mp 98–99 ЊC: IR (KBr pellet, cmϪ1) 1597,
1516, 1350 (SO2), 1181 (SO2); 1H NMR (DMSO-d6) δ 7.00–6.88
(m, 8 H, Ar-H), 4.57–4.45 (m, 4 H, –CH2CH2O–), 4.26–4.05
(m, 8 H, –CH2CH2O–), 3.85–3.75 (m, 4 H), 3.23 (s, 6 H,
CH3SO2OCH2CH2-); FAB MS m/z (Mϩ) calcd 534.12, found
534.20. Anal. calcd for C22H30O11S2: C, 49.43; H, 5.61. Found:
C, 49.21; H, 5.78%.
25,27-Bis(1-propyloxy)calix[4]arene dibenzo(dibutyl)crown-7,
1,3-alternate (5). Recrystallization from the oil residue with 5:1
diethyl ether–hexanes gave a white solid with 64% yield. Mp
179–181 ЊC; IR (KBr pellet, cmϪ1); 3068 (Ar-H), 1501, 1451,
1254, 1196; 1H NMR (CDCl3) δ 7.04–6.83 (m, 16 H), 6.78–6.70
(m, 4 H), 4.29 (t, J = 5.1 Hz, 2 H, –OCH(C4H9)CH2O–), 4.33–
4.19 (m, J = 5.1 Hz, 4 H), 4.07–4.00 (m, 4 H), 3.86–3.82 (m,
2 H), 3.64–3.40 (m, 6 H), 3.56 (s, 8 H, ArCH2Ar), 1.66-1.27 (m,
16 H), 0.92–0.85 (m, 12 H). FAB MS m/z (Mϩ) calcd 962.52,
found 962.50. Anal. calcd for C62H74O9: C, 77.29; H, 7.68.
Found: C, 77.30; H, 7.60%.
1,5-Bis[2-(1-butyl-2-methylsulfonyloxyethyloxy)phenoxy]-
3-oxapentane (13c). 95% of the desired product as a colorless oil
was obtained. IR (KBr pellet, cmϪ1) 1597, 1516, 1350 (SO2),
1
1180 (SO2); H NMR (CDCl3) δ 6.99–6.88 (m, 8 H, Ar-H),
4.43–4.35 (m, 6 H), 4.16 (t, 4 H), 3.92 (t, 4 H), 3.03 (s, 6 H,
CH3SO2O), 1.64–1.85 (m, 4 H), 1.31–1.42 (m, 8H), 0.89 (s, 6 H).
Anal. calcd for C30H46O11S2: C, 55.60; H, 7.11. Found: C, 55.62;
H, 7.13.%.
25,27-Bis(1-octyloxy)calix[4]arene dibenzocrown-8, 1,3-
alternate (6). Recrystallization from the oil residue with hexanes
gave the white solid with 92% yield. Mp 124–127 ЊC; IR (KBr
pallet, cmϪ1) 1593, 1501, 1455, 1254, 1208; 1H NMR (CDCl3) δ
7.08–6.91 (m, 16 H), 6.78–6.70 (m, 4 H), 4.23 (t, J = 5.1 Hz, 4 H,
–OCH2CH2O–), 4.08 (t, J = 5.0 Hz, 4 H, –OCH2CH2O–), 3.88
(t, J = 5.1 Hz, 4 H, –OCH2CH2O–), 3.73 (t, J = 5.1 Hz, 4 H,
–OCH2CH2O–), 3.71 (s, 8 H, ArCH2Ar), 3.44 (t, J = 7.4 Hz, 4
H, OCH2(CH2)6CH3), 1.80–1.40 (m, J = 7.4 Hz, 4 H, OCH2-
(CH2)6CH3), 0.91 (t, J = 7.4 Hz, 6 H, OCH2(CH2)6CH3); 13C
NMR (CDCl3) δ 157.5, 156.8 150.7, 149.8, 134.5, 134.0, 130.6,
1,8-Bis[2-(2-methylsulfonyloxyethyloxy)phenoxy]-3,6-dioxa-
octane (13d). 88% of the desired product was obtained as a
white solid. Mp 103–105 ЊC: IR (KBr pellet, cmϪ1) 1597, 1516,
1348 (SO2), 1180 (SO2); 1H NMR (CDCl3) δ 6.92–6.90 (m, 8 H,
Ar-H), 4.55–4.50 (m, 4 H, –CH2CH2O–), 4.54–4.12 (m, 8 H,
–CH2CH2O–), 3.85–3.82 (m, 4 H), 3.72 (S, 4H, –CH2CH2O–),
J. Chem. Soc., Perkin Trans. 2, 1999, 837–846
843