Synthesis of novel tris-crown ether structures

Article abstract of DOI:10.1055/s-2005-871536

Six unique tris-crown ether structures were successfully synthesized from trimethylolpropane triacrylate (TMPTA) with amino- and aza-crown ethers through Michael addition. The crown ethers contained a primary amine group such as 2-aminomethyl crown ethers and 4-aminobenzo crown ethers, others contained a secondary amine group, like 1-aza crown ethers. Georg Thieme Verlag Stuttgart.

Full text of DOI:10.1055/s-2005-871536

LETTER
1703
Synthesis of Novel Tris-Crown Ether Structures
N
Z
ovel Tris-Crow
h
n
EthersSt
i
ructures Bin Huang, Seung Hyun Chang*
Department of Chemistry, Daegu University, Kyongbuk, 712-714, Korea
Fax +82(53)8506449; E-mail: shchang@daegu.ac.kr
Received 25 March 2005
to synthesize tetra-crown ethers. TMPTA has the advan-
tage of low viscosity and high solubility in general organ-
ic solvents. In this letter, the tri-acrylate of TMPTA
served as the linker in the tris-crown ethers. We think that
Abstract: Six unique tris-crown ether structures were successfully
synthesized from trimethylolpropane triacrylate (TMPTA) with
amino- and aza-crown ethers through Michael addition. The crown
ethers contained a primary amine group such as 2-aminomethyl
crown ethers and 4-aminobenzo crown ethers, others contained a the newly synthesized tris-crown ethers contain superior
secondary amine group, like 1-aza crown ethers.
properties and applications, they can be widely applied in
Key words: amino-crown ether, aza-crown ether, tris-crown ether, the host–guest, supramolecular, synthetic and medicinal
TMPTA, Michael addition
chemistry fields in the future.
The synthetic approach to the six new novel structures of
tris-crown ethers is shown in Scheme 1.
The chemistry of crown ethers and crown-like compounds
has attracted a great deal of attention from various fields
of science since the first crown ether was discovered by
O
O
1
Pedersen in 1967. Numerous studies on crown ethers
HN
O
O
have been reported. In recent years, special interest has
been focused on the synthesis of multisite crown ether
compounds. Although a large number of bis-crown ethers
2
4 h
n = 1, tris-crown
ether 1 (83%)
n
n = 2, tris-crown
ether 2 (81%)
2
–28
have been reported
along with their synthesis and their
metal ion selectivity properties, only a few tris-crown
ethers have been synthesized.
O
O
O
O
2
9–33
NH2
24 h
O
O
Crown ethers are very effective complexing agents for
alkali and alkaline earth cations, and they are commonly
used in phase transfer reactions. If the size of the cation
closely matches that of the crown ether cavity, complexes
generally form in a 1:1 ratio. When the cation size exceeds
that of the crown cavity, the cation can only partially fit
and, as a result, a sandwich-type structure can be formed.
O
O
n = 1, tris-crown
ether 3 (74%)
n = 2, tris-crown
ether 4 (73%)
MeOH
50 °C
n
O
O
O
O
NH2
O
O
O
O
n = 1, tris-crown
ether 5 (73%)
n = 2, tris-crown
ether 6 (71%)
2
5–28
TMPTA
It has been reported
that the ‘bis-crown effect’ occurs
n
Et3N, 6 d
when two crown ether rings in one molecule bind a cation
in a sandwich-type structure, and it enables the molecules
to bind a cation that is larger than the ideal size for a Scheme 1 The approaches to the new tris-crown ethers
particular crown ether unit. The construction of multisite
molecular receptor molecules capable of binding two or
more guest metal cations is one current area of interest in
The structures of the six new tris-crown ethers, which
were synthesized through a Michael addition are outlined
in Figure 1. TMPTA was synthesized from trimethyl-
2
8,34–37
this field.
In this letter, we report the synthesis of
novel tris-crown ether structures, which are expected to
have superior properties and applications in various areas
which are different to bis-crown ether compounds. The
tris-crown ethers can capture not only the metal cations,
which are ideal sizes for the crown rings, but also two dif-
ferent metal cations of different sizes at the same time.
41
olpropane and acryloyl chloride in benzene. TMPTA
has three active double bonds at the end of each branch
chain. The primary and the secondary amine functional
groups of 2-aminomethyl crown ethers, 4-aminobenzo
crown ethers, and 1-aza crown ethers reacted with
TMPTA in methanol at 50 °C. Since the primary amine
group has two hydrogen atoms, the reagent/mole ratio of
the primary amine group to the double bond should be
greater than 1.5:1 to give a high yield of target product.
New tris-crown ethers 1 and 2 were prepared from
TMPTA with 1-aza-15-crown-5 and 1-aza-18-crown-6.42
Tris-crown ethers 3 and 4 were obtained from TMPTA
with 2-aminomethyl-15-crown-5 and 2-aminomethyl-18-
crown-6.43 Tris-crown ethers 5 and 6 resulted from the
Trimethylolpropane triacrylate (TMPTA) usually plays
an important role in the polymer field. It was reported3
that TMPTA can easily react with amines through
8,39
4
0
Michael addition. We have succeeded in using this idea
SYNLETT 2005, No. 11, pp 1703–1706
0
7
.0
7
.2
0
0
5
Advanced online publication: 14.06.2005
DOI: 10.1055/s-2005-871536; Art ID: U08805ST
©
Georg Thieme Verlag Stuttgart · New York

1
704
Z. B. Huang, S. H. Chang
LETTER
reaction of TMPTA with 4-aminobenzo-15-crown-5 and ether groups appeared as multiplets at 3.48–3.75 ppm.
4
4
4
-amino-benzo-18-crown-6. All the reactions took place The 1-aza-crown ether CH NCH proton chemical shift
2 2
under mild conditions. The functional groups reacted di- occurred at 2.75 ppm (triplets). The signals corresponding
rectly, and in only one step and the yields were all higher to the six protons in OCOCH CH N which connected the
2
2
than 70%. In our initial work, we found that the 4-ami- TMPTA core with the aza-crown ether nitrogen atom ap-
nobenzo crown ethers reacted with the acrylate double peared at 2.88 ppm (triplets). In the 5.8–6.5 ppm range,
bonds, and thus it could not be performed easily under the the double bond proton signals were not found, indicating
same conditions used above. The reactions proceeded as that the Michael addition had occurred. All new tris-
soon as triethylamine was added, as catalyst, and the reac- crown ethers were similar to 1. The chemical shift signals
tion was continued for six days to give the corresponding of the benzene ring protons of tris-crown ether 5 and 6 ap-
pure tris-crown ethers 5 and 6 with excellent yields of peared at 6.13–6.27 ppm and 6.77–6.79 ppm. The NH
about 70%. We think that the electron-rich benzene ring proton signals of tris-crown ethers 3–6 were not found,
contained in the 4-aminobenzo crown ethers reduced the presumably due to rapid exchange with the solvent
activity of the amine group.
protons.
In the H NMR spectra, resonances of the new tris-crown The 13C NMR spectra revealed that the removal of the
ethers were observed at the expected shifts. For example, double bond carbon signals which were located around
in the tris-crown ether 1, the ethereal protons of the crown 128 ppm and 131 ppm. The C=O carbon chemical shift
moved from 165 ppm to 173 ppm. The crown ether carbon
1
chemical shifts were seen around 69–70 ppm. All the
other chemical shifts of the tris-crown ethers occurred as
expected.
n
O
O
O
O
N
All the newly synthesized tris-crown ethers were analyzed
by mass spectrometry. The IR spectra revealed the crown
–
1
ether COC group absorption peaks at 1100–1130 cm as
expected.
O
O
O
O
O
O
O
O
O
O
We have developed a new efficient approach to synthesize
tris-crown ethers. The synthesis and characterization of
six new tris-crown ethers was described. The structures
are novel, the reaction conditions are gentle, and the yield
is high. The reactions can take place directly without
protection-deprotection. The tris-crown ethers show
promise to potentially carry different metal cations. We
plan to further investigate their ability as phase-transfer
catalysts and ionophores.
N
O
O
N
O
n
O
n = 1, tris crown ether 1
n = 2, tris crown ether 2
n
O
O
O
O
O
HN
O
Acknowledgment
O
O
O
O
This paper was partly supported by Daegu University 2003
Research Fund.
O
O
O
O
H
O
O
N
O
O
N
O
n
O
H
n
O
References
n = 1, tris crown ether 3
n = 2, tris crown ether 4
(1) Pedersen, C. J. J. Am. Chem. Soc. 1967, 89, 7017.
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O
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O
O
(4) Marchand, A. P.; McKim, A. S.; Kumar, K. A. Tetrahedron
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O
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HN
(
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O
O
O
O
O
O
O
(7) Kryatova, O. P.; Kolchinski, A. G.; Rybak-Akimova, E. V.
Tetrahedron 2003, 59, 231.
(8) Majerski, K. M.; Ramljak, T. S. Tetrahedron 2002, 58, 4893.
O
O
O
H
O
N
O
O
O
O
N
H
n
O
(
9) König, B.; Rütters, H. Tetrahedron Lett. 1994, 35, 3501.
n=1, tris crown ether 5
n=2, tris crown ether 6
(
(
10) Wong, K. H.; Ng, H. L. Tetrahedron Lett. 1979, 20, 4295.
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1984, 25, 2171.
Figure 1 The structures of new tris-crown ethers
Synlett 2005, No. 11, 1703–1706 © Thieme Stuttgart · New York

LETTER
Synthesis of Novel Tris-Crown Ether Structures
1705
(
12) Tarcali, J.; Nagy, G.; Tóth, K.; Pungor, E.; Juhász, G.;
Kukorelli, T. Anal. Chim. Acta 1985, 178, 231.
13) Beer, P. D.; Keefe, A. D. J. Organomet. Chem. 1986, 306,
C10.
J = 10.5 Hz, 3 H), 6.07–6.17 (dd, J = 10.8 Hz, 6.6 Hz, 3 H),
1
3
6.38–6.44 (d, J = 17.1 Hz, 3H); C NMR (75 MHz, CDCl3):
d = 165.87, 131.33, 128.27, 64.10, 40.88, 23.19, 7.41;
(
+
MS(GC): m/z = 296 [M] . Anal. calcd for C H O : C,
1
5
20
6
(
(
(
14) Beer, P. D.; Rothin, A. S. Polyhedron 1988, 7, 137.
15) Wang, D.; Sun, X.; Hu, H. Polyhedron 1989, 8, 2051.
16) Lukyanenko, N. G.; Nazarova, N. Y.; Vetrogon, V. I.; Holdt,
H. J.; Aurich, J.; Kuntosch, G. Inorg. Chim. Acta 1989, 155,
60.80; H, 6.80. Found: C, 60.68; H, 6.81.
(42) Tris-crown ether 1: TMPTA (30 mg, 0.1 mmol) and 1-aza-
15-crown-5 (88 mg, 0.4 mmol) were dissolved in MeOH (5
mL), the reaction was stirred at 50 °C; after 24 h the solvent
was evaporated in vacuo and purified via column
3
5.
17) Chang, S. H.; Kim, J. Y. J. Korean Chem. Soc. 1994, 38,
77.
18) Chang, S. H.; Kim, J. Y. J. Korean Chem. Soc. 1996, 40,
35.
19) Suzanne, F. F.; Fatima, A. A. J. Photochem. Photobiol., C
004, 5, 139.
20) Bourguignon, J.; Bremberg, U.; Dupas, G. Tetrahedron
003, 59, 9583.
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
(
chromatography on silica gel (EtOAc), affording tris-crown
ether 1 as a yellow oil (79 mg, isolated yield 82.8%). IR
(NaCl): 2921.6, 2878.3, 1957.4, 1730.8, 1581.4, 1458.9,
1393.3, 1355.7, 1297.9, 1252.5, 1196.6, 1119.5, 1062.6,
3
6
–
1 1
989.3, 940.1, 852.4, 829.2, 778.1 cm ; H NMR (300 MHz,
2
CDCl ): d = 0.84 (t, J = 7.5 Hz, 3 H), 1.22–1.27 (q, 2 H),
3
2.49 (t, J = 7.2 Hz, 6 H), 2.75 (t, J = 6.0 Hz, 12 H), 2.88 (t,
1
3
2
J = 7.5 Hz, 6 H), 3.48–3.75 (m, 54 H); C NMR (75 MHz,
21) Julian, R. R.; May, J. A.; Stoltz, B. M.; Beauchamp, J. L. Int.
J. Mass Spectrom. 2003, 228, 851.
22) Kryatova, O. P.; Korendovych, I. V.; Rybak-Akimova, E. V.
Tetrahedron 2004, 60, 4579.
CDCl ): d = 173.16, 70.96, 70.38, 70.16, 69.92, 66.58,
3
54.47, 51.98, 42.75, 32.49, 23.09, 7.50; MS (EI): m/z = 954.5
+
+
[M] ; MS (FAB): m/z = 955.4 [M + H] ; Anal. calcd for
C H N O : C, 56.65; H, 8.77; N, 4.40. Found: C, 56.38; H,
4
5
83
3
18
23) Sousa, C.; Gammero, P.; Freire, C.; Castro, B. Polyhedron
8.81; N 4.32.
2004, 23, 1401.
Tris-crown ether 2: TMPTA (30 mg 0.1 mmol) and 1-aza-
18-crown-6 (105 mg 0.4 mmol) were dissolved in MeOH (5
mL), the reaction was carried out as above, to afford a yellow
oil (88 mg, isolated yield 81.0%). IR (NaCl): 2877.3, 2500.3,
1968.9, 1730.8, 1644.0, 1577.5, 1459.9, 1352.8, 1289.2,
24) Taraszewska, J.; Zieba, K.; Korybut-Daszkiewicz, B.
Electrochim. Acta 2004, 49, 2675.
25) Kimura, K.; Sakamoto, H.; Koseki, Y.; Shono, T. Chem.
Lett. 1985, 1241.
–
1 1
26) Beer, P. D.; Crane, C. G.; Danks, J. P.; Gale, P. A.; McAleer,
J. F. J. Organomet Chem. 1995, 490, 143.
27) Lee, L.-H.; Lynch, V.; Lagow, R. J. J. Chem. Soc., Perkin
Trans. 1 2000, 2805.
1249.7, 1110.8, 988.3, 951.7, 835.0, 777.2 cm ; H NMR
(300 MHz, CDCl ): d = 0.84 (t, J = 7.5 Hz, 3 H), 1.22–1.27
3
(q, 2 H), 2.48 (t, J = 7.2 Hz, 6 H), 2.77 (t, J = 6.0 Hz, 12 H),
2.88 (t, J = 7.2 Hz, 6 H), 3.46–3.70 (m, 66 H); C NMR (75
1
3
28) Berry, N. G.; Shimell, T. W.; Beer, P. D. Supramol. Chem.
MHz, CDCl ): d = 173.19, 70.83, 70.72, 70.70, 70.49, 70.45,
3
2
002, 2, 89.
29) Uda, R. M.; Oue, M.; Kimura, K. J. Supramol. Chem. 2002,
, 311.
30) Buchanan, G. W.; Azad, M.; Yap, G. P. A. J. Mol. Struct.
001, 598, 145.
70.36, 70.25, 70.17, 70.03, 69.80, 65.55, 53.85, 51.56,
42.80, 32.43, 22.89, 7.53; MS(FAB): m/z = 1087.4 [M + H] .
+
2
Anal. calcd for C H N O : C, 56.39; H, 8.81; N, 3.87.
5
1
95
3
21
Found: C, 56.12; H, 8.90; N, 3.78.
2
(43) Tris-crown ether 3: TMPTA (30 mg, 0.1 mmol) and 2-
aminomethyl-15-crown-5 (125 mg, 0.5 mmol) were
dissolved in MeOH (5 mL), the reaction was carried out as
above, to afford tris-crown ether 3 as a slight yellow oil (77
mg, isolated yield 73.8%). IR (NaCl): 2926.5, 2880.2,
1731.8, 1644.0, 1596.8, 1460.8, 1382.1, 1354.8, 1250.6,
1194.7, 1117.6, 1061.6, 989.3, 947.8, 871.7, 844.7, 778.1
31) Morey, J.; Orell, M.; Barcel, M.; Deyà, P. M.; Costa, A.;
Ballester, P. Tetrahedron Lett. 2004, 45, 1261.
32) Costero, A. M.; Andreu, C.; Monrabal, E.; Tortajada, A.;
Ochando, L. E.; Amigó, J. M. Tetrahedron 1996, 52, 12499.
33) Weber, E.; Skobridis, K.; Ouchi, M.; Hakushi, T.; Inoue, Y.
Bull. Chem. Soc. Jpn. 1990, 63, 3670.
–
1 1
(
(
34) Lehn, J. M. Pure Appl. Chem. 1980, 52, 2441.
35) Carroy, A.; Lehn, J. M. J. Chem. Soc., Chem. Commun.
cm ; H NMR (300 MHz, CDCl ): d = 0.84 (t, J = 7.8 Hz, 3
3
H), 1.22–1.27 (q, 2 H), 2.51 (t, J = 6.6 Hz, 6 H), 2.70 (d,
J = 6.0 Hz, 6 H), 2.88 (t, J = 6.6 Hz, 6 H), 3.58–3.78 (m, 66
1
986, 1232.
36) Chambron, J. C.; Sauvage, J. P. Tetrahedron Lett. 1986, 27,
65.
1
3
(
H); C NMR (75 MHz, CDCl ): d = 173.05, 70.90, 70.64,
3
8
70.53, 70.45, 66.49, 51.57, 50.21, 42.75, 32.56, 23.04, 7.48;
+
(
(
37) Beer, P. D. J. Chem. Soc., Chem. Commun. 1986, 1678.
38) Xu, D. M.; Zhang, K. D.; Zhu, X. L. J. Appl. Polym. Sci.
MS (FAB): m/z = 1044.5 [M + H] . Anal. calcd for
C H N O : C, 55.21; H, 8.59; N, 4.02. Found: C, 54.94; H,
4
8
89
3
21
2
004, 92, 1018.
39) Huang, Z. B.; Zhang, K. D.; Liang, Y. J. Chem. Res. Appl.
China) 2003, 15, 718.
40) H uang, Z. B.; Kang, T. J.; Chang, S. H. Tetrahedron Lett.
005, 46, 3461.
8.62; N, 3.95.
(
(
(
Tris-crown ether 4: TMPTA (30 mg, 0.1 mmol) and 2-
aminomethyl-18-crown-6 (147 mg, 0.5 mmol) were
dissolved in MeOH (5 mL), operated the same as above,
afforded tris-crown ether 4 as a slight yellow oil (86 mg,
isolated yield 73.1%). IR (NaCl): 2922.6, 2881.1, 1730.8,
1665.2, 1592.0, 1461.8, 1384.6, 1352.8, 1285.3, 1249.7,
(
2
41) TMPTA: Trimethylolpropane (13.42 g, 0.1 mol) was
dissolved in benzene (50 mL). Pyridine (3 mL) was added
and the mixture stirred for 30 min. In an ice bath acryloyl
chloride (29.90 g, 0.33 mol) was added dropwise to the flask
over 3 h, then the reaction was stirred below 50 °C. After 30
h the solution was washed with aqueous K CO (2 N, 20
–
1
1187.9, 1107.9, 1060.7, 989.3, 882.3, 835.0, 777.2 cm ;
1
H NMR (300 MHz, CDCl ): d = 0.83 (t, J = 7.8 Hz, 3 H),
3
1.22–1.27 (q, 2 H), 2.52 (t, J = 6.9 Hz, 6 H), 2.70 (d, J = 6.0
Hz, 6 H), 2.89 (t, J = 6.6 Hz, 6 H), 3.53–3.82 (m, 78 H);
2
3
1
3
mL), water (3 × 20 mL), active carbon was added, and the
mixture was dried over magnesium sulfate for 12 h. After
filtration, the solvent was evaporated and filtered again
through a pad of silica to give a colorless oil (24.1 g, isolated
yield 81%). H NMR (300 MHz, CDCl ): d = 0.94 (t, J = 7.5
C NMR (75 MHz, CDCl ): d = 173.09, 70.95, 70.71, 70.52,
3
70.45, 70.31, 70.01, 69.55, 69.52, 65.76, 51.68, 50.15,
42.84, 32.57, 22.78, 7.44; MS (FAB): m/z = 1177.6 [M +
+
H] . Anal. calcd for C H N O : C, 55.13; H, 8.65; N,
5
4
101
3
24
1
3.57. Found: C, 54.89; H, 8.57; N, 3.53.
3
Hz, 3 H), 1.53–1.61 (q, 2 H), 4.18 (s, 6 H), 5.83–5.88 (d,
Synlett 2005, No. 11, 1703–1706 © Thieme Stuttgart · New York

1
706
Z. B. Huang, S. H. Chang
LETTER
Tris-crown ether 6: TMPTA (30 mg, 0.1 mmol) and 4-
(
44) Tris-crown ether 5: TMPTA (30 mg, 0.1 mmol) and 4-
aminobenzo-15-crown-5 (142 mg, 0.5 mmol) were
aminobenzo-18-crown-6 (163 mg, 0.5 mmol) were
dissolved in MeOH (6 mL), affording tris-crown ether 6 as a
deep brown oil (91 mg, isolated yield 71.2%). IR (NaCl):
3367.1, 3037.4, 2917.8, 2880.2, 1967.0, 1729.8, 1617.0,
1516.7, 1455.0, 1408.8, 1354.8, 1280.5, 1230.4, 1186.0,
dissolved in MeOH (6 mL), triethylamine(catalyst) was
added and the reaction was continued for six days at 50 °C.
The reaction afforded tris-crown ether 5 as a red brown oil
(
84 mg, isolated yield 73.3%). IR (NaCl): 3364.2, 3037.4,
–
1 1
2
1
9
924.5, 2871.5, 1965.1, 1726.0, 1615.1, 1513.9, 1455.0,
1117.6, 989.3 cm ; H NMR (300 MHz, CDCl ): d = 0.85
3
408.8, 1357.6, 1226.5, 1184.1, 1123.3, 1057.8, 984.5,
(t, J = 7.5 Hz, 3 H), 1.22–1.27 (q, 2 H), 2.60 (t, J = 6.3 Hz, 6
H), 3.37 (t, J = 6.3 Hz, 6 H), 3.62–3.76 (m, 42 H), 3.84–3.93
(m, 12 H), 4.02–4.12 (m, 12 H), 6.13–6.27 (dd, ArH, 6 H),
–1 1
39.2 cm ; H NMR (300 MHz, CDCl ): d = 0.84 (t, J = 7.5
3
Hz, 3 H), 1.22–1.27 (q, 2 H), 2.61 (t, J = 6.3 Hz, 6 H), 3.39
t, J = 6.6 Hz, 6 H), 3.67–3.75 (m, 30 H), 3.86–3.91 (m, 12
H), 4.05–4.11 (m, 12 H), 6.13–6.27 (dd, ArH, 6 H), 6.77–
1
3
(
6.76–6.79 (d, ArH, 3 H); C NMR (75 MHz, CDCl ): d =
3
172.88, 150.43, 143.22, 141.30, 117.51, 104.85, 101.20,
70.82, 70.78, 70.75, 70.71, 70.65, 70.56, 70.48, 69.93,
69.67, 69.63, 68.81, 67.91, 51.73, 40.11, 33.65, 22.57, 7.53;
1
3
6
1
7
5
.79 (d, ArH, 3 H); C NMR (75 MHz, CDCl ): d = 172.91,
3
50.43, 143.19, 141.61, 117.48, 104.80, 101.03, 70.89,
0.80, 70.73, 70.43, 70.39, 69.92, 69.58, 69.55, 67.92,
1.76, 40.17, 33.68, 23.78, 7.44; MS (FAB): m/z = 1146.4
+
MS (FAB): m/z = 1278.6 [M + H] . Anal. calcd for
C H N O : C, 59.19; H, 7.49; N, 3.29. Found: C, 59.37; H,
6
3
95
3
24
+
[
M + H] . Anal. calcd for C H N O : C, 59.72; H, 7.30; N,
7.43; N, 3.22.
5
7
83
3
21
3.67. Found: C, 59.84; H, 7.41; N, 3.62.
Synlett 2005, No. 11, 1703–1706 © Thieme Stuttgart · New York