Reaction of bis(2-chloroethyl)amine with
bis(2-mercaptoethyl)sulfide
added and the organic layer was washed with saturated aqueous
NaHCO3 solution and water. The chloroform layer was dried over
Na2SO4 and concentrated to give 1 (88%, 0.021 g) or 2 (84%,
0.089 g).
A mixture of bis(2-chloroethyl)amine hydrochloride1a (1.00 g,
5.60 mmol), bis(2-mercaptoethyl)slufide (0.86 g, 5.60 mmol) and
lithium hydroxide monohydrate (1.38 g, 33.6 mmol) in THF
(450 mL) was refluxed under a nitrogen atmosphere for 7 days.
The reaction mixture was filtered and then concentrated in
vacuo. The residue was extracted with chloroform twice and the
extractant was washed with water. After drying over anhydrous
sodium sulfate, the solvent was removed. The crude product was
recrystallized from hexane and then heptane to give 1 (4.8%,
0.060 g), a 2 : 1 mixture of 1 and 2 (21.6%, 0.268 g estimated
as 1), and 2 (1.8%, 0.022 g).
N,Nꢀ-Bis(3ꢀ,5ꢀ-dichlorobenzyl)diazahexathia-24-crown-8 (5a)
After a mixture of 3,5-dichlorobenzaldehyde (0.260 g, 1.50 mmol)
and 2 (0.219 g, 0.50 mmol) in dry 1,2-dichloroethane (10 mL)
was stirred at room temperature for 1 day under a nitrogen
atmosphere, triacetoxysodium borohydride (0.424 g, 2.00 mmol)
and 1,2-dichloroethane (10 mL) were added and the mixture was
stirred at room temperature for 3 days. Saturated aqueous Na2CO3
was added and the aqueous layer was extracted with chloroform
(3 × 20 mL). The combined organic layers were washed with
water, dried over Na2SO4, and concentrated. The residual oil
was recrystallized from chloroform–acetonitrile to give 5a in 52%
(0.199 g). Mp 129.5–130.0 ◦C; dH (400 MHz; CDCl3; Me4Si) 7.31
(d, J = 1.70 Hz, 4H), 7.26 (t, J = 1.70 Hz, 2H), 3.59 (s, 4H), 2.85–
2.76 (m, 16H), 2.76–2.65 (m, 16H); m/z (m-NBA as a matrix): 765
([M + 1]+, 20%). Found: C, 46.97; H, 5.81; N, 3.23. C30H42N2S6Cl4
requires C, 47.11; H, 5.53; N, 3.66%.
Ligand 1. Mp 82.0–83.0 ◦C; dH (400 MHz; CDCl3; Me4Si)
2.97–2.82 (m, 12H), 2.75 (t, J = 5.5 Hz, 4H), 1.60 (s, 1H); m/z
(m-NBA as a matrix) 224 ([M + 1]+, 100%).
Ligand 2. Mp. 83.5–84.0 ◦C; dH (400 MHz; CDCl3; Me4Si)
2.86 (t, J = 6.1 Hz, 8H), 2.8 (s, 16H), 2.75 (t, J = 6.1 Hz, 8H), 1.58
(s, 1H); m/z (m-NBA as a matrix) 447 ([M + 1]+, 100%); found:
C, 43.01; H, 7.67; N, 6.27. C16H34N2S6 requires C, 43.32, H, 7.38,
N, 6.23%.
N,Nꢀ-Bis(2ꢀ-phenylethyl)diazahexathia-24-crown-8 (5b)
Reaction of N-Boc-bis(2-chloroethyl)amine with
2-mercaptethylsulfide
The preparation procedure was the same as that used for 5a. Yield
55% (0.180 g); mp 67.0–68.0 ◦C; dH (400 MHz; CDCl3; Me4Si)
7.31–7.16 (m, 10H), 2.84–2.71 (m, 32H), 2.64 (t, J = 6.8 Hz, 8H);
m/z (Fm-NBA as a matrix) 655 ([M + 1]+, 100%). Found: C, 58.44;
H, 7.48; N, 4.11. C32H50N2S6 requires C, 58.66; H, 7.69; N, 4.28%.
N-Boc-bis(2-chloroethyl)amine (1.74 g, 7.22 mmol), bis(2-
mercaptoethyl)sulfide (1.01 g, 6.50 mmol) and lithium hydroxide
(1.82 g, 43.4 mmol) in THF (400 mL) was refluxed under a nitrogen
atmosphere for 7 days. The reaction mixture was purified by
column chromatography on silica-gel (gradient elution method:
ethylacetate–hexane = 1 : 20, 1 : 5, and then 1 : 4) to give N-Boc-
protected macrocycles 3 and 4 in 16% (0.338 g) and 6.5% (0.138 g)
yields, respectively.
Preparation of AgOTf complexes
AgOTf (0.03 mmol) in acetonitrile (1 mL) was treated with
host (0.01 mmol) in acetonitrile (1 mL). After the solvent had
evaporated, the crystals were obtained to give the AgOTf complex
quantitatively.
Macrocycle 3. Mp (decomp.) > 141 ◦C; dH (400 MHz; CDCl3;
Me4Si) 3.46 (s, 4H), 2.74–2.79 (m, 12H), 1.45(s, 9H); m/z (m-NBA
as a matrix) 324 ([M + 1]+, 50%); Found: C, 48.13; H, 7.59; N, 3.79.
C13H25NO2S3 requires C, 48.26; H, 7.79; N, 4.33%.
AgOTf complex of 5a. Mp (decomp.) 150.0–150.6 ◦C; Found.
C, 29.91; H, 3.36; N, 2.21. C32H42N2F6O6S8Cl4Ag2 requires C,
30.06; H, 3.31; N, 2.19%; m/z (m-NBA as a matrix) 1279 ([M
+ 2Ag + 2OTf]+), 1128 ([M + 2Ag + OTf]+), 1021 ([M + Ag +
OTf]+), 978 ([M + 2Ag]+), 871 ([M + Ag]+).
Macrocycle 4. Mp (decomp.) > 95 ◦C; dH (400 MHz; CDCl3;
Me4Si) 3.43 (s, 8H), 2.70–2.86 (m, 24H), 1.46 (s, 18H); m/z (m-
NBA as a matrix) 647 ([M + 1]+, 5%); Found: C, 47.75; H, 7.51; N,
3.46. C26H50N2O4S6H2O requres C, 47.60; H, 7.84; N, 4.27%. The
combustion analysis for 3 and 4 have been carried out twice for
differentbatches ofproduct, andallanalyticaldatawerealmostthe
same. The observed contents of nitrogen in the N-Boc-protected
azathiacrown ethers were less than the calculated values, because
these compounds are not stable. Combustion analysis was not
carried out for N-Boc protected monoazatetrathia-16-crown-6 in
the previous paper.4
AgOTf complex of 5b. Mp (decomp.) 140.0–144.0 ◦C; Found.
C, 34.85; H, 4.61; N, 2.26. C34H50N2F6O6S8Ag2 requires C, 34.93;
H, 4.31; N, 2.40%; m/z (m-NBA as a matrix) 1276 ([M + 3Ag +
2OTf]+), 1019 ([M + 2Ag + OTf]+), 869 ([M + 2Ag]+), 763 ([M +
Ag]+).
1H NMR titration experiments
Titration experiments were carried out by addition of 0.1–5.0
equivalents of AgOTf in a mixture of CD2Cl2–CD3OD (1 : 1)
(0.002 mmol lL−1) to 5a or 5b in a mixture of CD2Cl2–C3OD (1 :
1) (0.02 mmol per 0.65 mL) at 298 K.
Removing the Boc groups from 3 and 4
N-Boc-protected azathiacrown ethers, 3 (0.104 mmol) or 4
(0.212 mmol), were dissolved in 40%-CF3COOH in dichloro-
methane (50 mL). After the mixture was stirred at room temper-
ature for 10 min and the solvent was removed in vacuo, methanol
(30 mL) was added to the residue and evaporated. The procedure
was repeated twice. To the residual oils, chloroform (50 mL) was
X-Ray structure determination
The crystals of the AgOTf complexes of 5a and 5b were mounted
on the top of a glass fiber, and the data collections were carried
out on Bruker SMART CCD area diffractometer at 90 K. Data
This journal is
The Royal Society of Chemistry 2006
Dalton Trans., 2006, 2202–2206 | 2205
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