Supporting Information
One-pot synthesis of tweezer-like calix[4]resorcinarene decorated
with pendant heterocyclic moieties; An efficient and recyclable
heterogeneous PTC for the preparation of azidohydrins in water
Arash Mouradzadegun, Somayeh Elahi and Fatemeh Abadast
Department of Chemistry, Faculty of Science, Shahid Chamran University, Ahvaz, Iran
Fax +98(611)3337009; Tel +98(611)3331042
Corresponding
Author E-mail: arash_m@scu.ac.ir
Table of Contents
Pages
1 Experimental section
2
1.1 General
1.2 Synthesis of tweezer-like dicationic calix[4]resorcinarene
1.3 Synthesis of azidohydrins by using novel phase transfer catalyst
2 Spectral data
2.1 Calix[4]resorcoinarene (1)
3
2.2 Novel tweezer like calix[4]resorcinarene (2)
3
3- Copy of IR, 1H NMR and 13C NMR spectra
3.1 Calix[4]resorcoinarene (1)
5
3.2 Novel tweezer like calix[4]resorcinarene (2)
8
3.3 Some of compound in table 1
12
1
1- Experimental Section
2.1 General
Chemicals were purchased from Fluka, Merck and Aldrich chemical companies and used without
further purification. Products were characterized by physical data, IR, 1H and
13
C NMR. IR spectra
were obtained on a Bomen MB:102 FT-IR spectrophotometer. 1H and 13C NMR spectra were recorded
on a Brucker spectrometer at 400 and 100 MHz, respectively, in CDCl3 or DMSO. Elemental analysis
was performed at Thermo Finnigan Flash EA 1112 CHNS-Analyzer and thermal stability of the
catalyst was investigated by NETZSCH STA 409 PC/PG.
2.2 Synthesis of tweezer-like dicationic calix[4]resorcinarene (2)
The mixture of 12 mmol (3-chloropropyl)trimethoxysilane and 12 mmol of 1-methylimidazole
(freshly distilled) was refluxed at 95˚C for 24 h under nitrogen atmosphere. The reaction mixture was
cooled down and 1-methyl-3-(trimethylsilylpropyl) imidazolium chloride ([pmim]Cl) (slightly yellow
viscous oil) was obtained with 98% yield [13]. Then, 0.5 g (1 mmol) of calix[4]resorcinarene in 10
mL of toluene was added to 1.5 g (6 mmol) of [pmim]Cl. After heating the slurry at 90˚C for 24 h the
solid was isolated by filtration. Owing to the solubility of unreacted calix[4]resorcinarene in ethanol
and 3-chloro trimethoxysilane, methyl imidazole and ([pmim]Cl) in water, the resulting solid was
washed several times with ethanol and distilled water to remove unreacted materials. Then, the solid
was dried under high vacuum to give violet powder with 89% yield.
2.3 Synthesis of azidohydrin derivatives in the presence of novel phase transfer catalyst (2)
NaN3 (2 mmol) was added to a mixture of epoxide (1 mmol) and dicationic calix[4]resorcinarene
(0.03 g) in water (1.5 mL). The suspension was magnetically stirred at 70˚C for the lengths of time
shown in Table 1. After completion of the reaction as judged by TLC (using n-hexane/ethyl acetate
(4:2) as eluent), the catalyst was removed by filtration. The products were obtained upon extraction
with ethyl acetate (3 × 5 mL). The extract was dried over CaCl2, and then solvent was evaporated
under high vacuum to give the azidohydrins.
The recovered catalyst was washed with water, ethanol and ethyl acetate, respectively. Then was dried
under vacuum after each cycle and reused for the next reaction.
2
2 Spectral Data
2.1 Calix[4]resorcinarene (1)
2,8,14,20-tetraalkylpentacyclo-[19.3.1.1.1.1]octacosa-1(25),3,5,7,(28),9,11,13 (27),15,17,
19(26),21,23-dodecane-4,6,10,12,16,18,22,24-octol ( 1, calix[4]resorcinarene, C32H32O8)
Yield 60%; white powder; m.p. > 360 ˚C; νmax/cm-1 = 3000-3500 (OH); δH (400 MHz;
DMSO-d6) 1.29-1.30 (12H, d, 3JHH= 6.8, CH3), 4.43-4.49 (4H, q, 3JHH= 6.8, Hl), 6.15 (4H, s,
Hi), 6.76 (4H, s, Hj), 8.56 (8H, s, OH) ppm. δC (100MHz, DMSO-d6): 22.0 (C-m), 29.0 (C-l),
102.5 (C-n), 123.5 (C-i), 125.7 (C-o), 152.3 (C-j) ppm.
HO
OH
k
OH
no
HO
HO
CH3 H3C
j
m
CH3 H3C
i
OH
l
HO
OH
3
2.2 Tweezer-like calix[4]resorcinarene (2, C46H58 N4Si2O12Cl2)
Yield 89%; pale violet powder; mp 260 ˚C; δH (400 MHz; DMSO-d6) 0.54 (4H, br s, Ha),
1.33 (12H, t, Hm), 1.77 (4H, m, Hb), 3.77 (6H, s, Hg), 4.42 (4H, q, Hl), 4.15 (4H, m, Hc), 6.15
(4H, s, Hi), 6.48 (4H, s, Hj), 7.36-7.90 (4H br m, He,f), 8.77 (6H, br s, Hk), 9.45 (2H, br s, Hd)
ppm. δ C (400MHz; DMSO-d6): 8.9 (C-a), 21.77 (C-m), 23.92 (C-b), 28.91 (C-l), 36.04 (C-g),
51.18 (C-c), 102.961(C-o), 122.67 (C-e, C-f), 123.72 (C-i), 125.351(C-n), 137.311 (C-d),
152.53 (C-j) ppm.
g
CH3
f
N
e
d
N
HO
HO
b
a
Si
O
HO
n
CH3 H3C
j
m
CH3 H3C
HO
O
Si
Cl N
N
CH3
4
k
OH
o
OH
OH
OH
h
OH
i
l
HO
Cl
c
3.3 Copy of 1H NMR, 13C NMR, IR Spectra of novel compound
3.1 Calix[4]resorcinarene (1)
H
CH3
H
CH3
CH3
5
CH3
k
a
m
a
i
j
a
J = 6.8 HZ
l
a
a
m
a
l
a
6
J = 6.8 HZ
j
a
i
a
m
n
o
a
a
7
l a
a
3.2 Tweezer-like calix[4]resorcinarene (2)
CH3
CH3
N
N
N
N
-
-
Cl
Cl
OH
HO
OH
Si
CH3
HO
CH3
Si
CH3
CH3
m
a
i
a
c
j
a
l
a
d
k
a
a
e,f
a
a
8
g
a
b
a
a
a
a
a
i
a
j
e
n ,
f
d
l
o
a
m
a
a
c
g
b
a
a
a
a
a
a
a
9
The structure of prepared compound (2) was fully characterized by 1H,
13
C NMR and elemental
analysis.
The 1H NMR spectrum of compound (2) in DMSO-d6 show the proton signal of four methine bridging
at 4.42 ppm (4H), the protons at C-2 and C-5 position of resorcinol ring show two single peaks in 1:1
ratio at 6.15 (4H) and 6.84 ppm (4H) and the four methyl groups show doublet peak at 1.33 ppm
(12H). Six hydroxyl groups show a broad singlet at 8.77 ppm (6H). The proton signal of Si-CH2, SiCH2-CH2 and Si-CH2-CH2-CH2-N groups appear at about 0.54 ppm (4H), 1.77 ppm (4H) and 4.15
ppm (4H), respectively. The peak of the Si-OH at about 3.14 ppm cannot generally be resolved due to
its overlap with the signal of water of the used solvent in the same range. Two methyl groups on
imidazolium ring show singlet peak at 3.77 ppm (6H). Imidazolium group also show two broad peak
at 7.63-7.90 ppm for N-CH=CH-N (4H) and at 9.45 ppm for N-CH-N (2H). This peak integrates to
one compared to the two methine bridging head protons, proving the bis-imidazolium armed
resorcinarene is formed. The 13C NMR spectrum in DMSO-d6 shows a signal at 28.91 ppm for four
methine bridging. The carbon at C-2 and C-5 position of resorcinol ring show two peaks at 123.72 and
152.53 ppm, other carbon of resorcinol ring show two peak at 102.96 and 125.35 ppm and the four
methyl groups show peak at 21.77 ppm. The carbon signal of Si-CH2, Si-CH2-CH2 and Si-CH2-CH2CH2-N groups appear at about 8.9, 23.92 and 51.18 ppm, respectively. Imidazolium group show peak
at 122.67 and 137.311 ppm for N-CH=CH-N and N-CH-N, respectively. Two methyl groups on
imidazolium ring show peak at 36.04 ppm. Inspection of the
13
C NMR revealed that, there is no
detectable signal for Si-OCH3 group at about 45 ppm, confirming the conversion of Si-OCH3 into SiOH.
It is noteworthy that, in unsubstituted resorcinarenes (1), the eight hydroxyl groups form a cyclic
array of intramolecular hydrogen bonds that rigidify the structure and stabilize the cone conformation.
Hence, in their 1H NMR spectra sharp signals appear for all groups of protons [1].
When the resorcinol oxygen atoms in calix[4]resorcinarene (1) are bridged with imidazolium unit,
require breaking the ring of four intramolecular hydrogen bonds, the flexibility of the resorcinarene
skeleton increases [2] (fluctuate between conformations), and in their 1H NMR spectra broad signals
10
were found for all proton groups of compound (2). The 1H NMR and 13C NMR spectrums indicate
that two imidazolium salts built on calix[4]resorcinarene skeleton.
[1] M. Urbaniak, W. Iwanek, Tetrahedron, 60 (2004) 8265-8273.
[2] (a) V. Bohmer, A. Shivanyuk, Calixarenes in action, eds. l. Mandolini, R. Ungaro, Imperial
College press, London, 2000; p. 225 (b) S. Strandman, H. tenhu, Polymer, 48 (2007) 3938-3951.
(c) R. Zhou, J.C. Ren, C.G. Yan, Journal of Inclusion Phenomena and Macrocyclic Chemistry 67
(2010) 335-342.
11
3.3 Some of compounds in table 1
g
f
e
OH
d O
N3
c b a
g
e
f
12
J = 8 HZ
g
e
c
f a
a
a
J = 8 HZ
a
a
b
a
h
a
a
g
e
b,c
a
f
a
d
13
a
g
OH
b
a
O
c
d
14
e
N3
f
a
a
b
a
15
d,e
ac
f
a
a
h
OH
c
O
a
b
d
16
e f g
N3
d,g
a
e
h
a
f
cb
a
aa
a
a
a
g
ef
d a
aa
a
c
a
b
a
a
a
17
J = 7.2 HZ