Synthesis of new aza macrocyclic diamides 2,2'-diaminodiphenyl sulfide using crab-like method

Article abstract of DOI:10.1002/jhet.775

Six new aza crown ethers (4-9) were synthesized based on the conventional route crab-like method with the reaction of corresponding bis-α- chloroacetamidediphenylsulfide (BCADPS) (3) and aliphathic diamines (a-e) in refluxing acetonitrile in good yields.

Full text of DOI:10.1002/jhet.775

May 2012
Synthesis of New Aza Macrocyclic Diamides
,2 -Diaminodiphenyl Sulfide Using Crab-Like Method
499
0
2
Abbas Shockravi* and Mahmood Kamali
Faculty of Chemistry, Tarbiat Moallem University, 15614 Tehran, Iran
*
E-mail: abbas_shockravi@yahoo.co.uk
Received July 4, 2010
DOI 10.1002/jhet.775
View this article online at wileyonlinelibrary.com.
O
Cl
Cl
O
O
O
O
N
NH
NH
NH2
NH2
N
H
N
H
HN
O
NH
HN
S
S
+
S
Z
S
Z
S
H
N
H
N
H
N
N
O
O
2
3
4-8
9
Six new aza crown ethers (4–9) were synthesized based on the conventional route crab-like method with
the reaction of corresponding bis-a-chloroacetamidediphenylsulfide (BCADPS) (3) and aliphathic diamines
0
(
a–e) in refluxing acetonitrile in good yields. BCADPS (3) was synthesized with the reaction of 2,2 -
diaminodiphenyl sulfide (2) and chloroacetyl chloride. Interestingly, only the macrocyclization of BCADPS
3) with diamine (e) was led to the cryptand (9) in which methylene hydrogens were found as diastereotopic
(
nucleis which is attributed to the rigidity of the cryptand (9). The formation of this cryptand (9) may be related
1
the template effect of potassium ion. The structures of all compounds were confirmed using IR, H-NMR,
13
C-NMR, mass spectroscopies, and elemental analysis.
J. Heterocyclic Chem., 49, 499 (2012).
INTRODUCTION
The method for the preparation of macrocylic diamides
and corresponding aza crown compounds have been exten-
sively reviewed [9]. Among these methods, the high
dilution-techniques [10], the route base template effect
Since Pedersen’s discovery [1], crown ethers have been
intensively investigated macrocyclic compounds due to their
facile synthesis and almost infinite possibilities of chemical
modifications as host compounds. Aza crown macrocyclic
compounds have gained a great deal of attention due to
their wide applications in chemistry, metal separation,
sensoring, analysis, biology, microanalysis, biophysics, and
ecology [2,3].
A rational design of macromolecular receptors is gov-
erned by a number of factors (the nature, the number,
the relative structural, and spatial placement of various
ligating units, etc.), and the combination of these factors
may induce an intrinsic balance of noncovalent binding
forces optimum for specificity in host-guest recognition
[11], and the high pressure approach [12] are frequently
used. Krakowiak et al. have developed a method based
on the using bis(a-chloroamides) for preparation of
corresponding aza crown compounds known as “crab-like”
cyclization method [13] in good yield. Izatt and coworkers
have used their methodology with appropriate dithiols in
the presence of sodium or cesium carbonate to prepare
the macrocycles in yields of about 40% [14]. These macro-
cycles were also synthesized by forming two C—N bonds
in the ring closure step in which diacylation of diamines
using diacid dichlorids [15,16a,b, diisocyanates [17], or
diesters [16b,c,18 were used as diacylation agents. Aza thia
macrocycles were also prepared by the interaction of diso-
[
4]. The amide group, so generously used by nature in a
variety of antibiotic ionophores [5], has acquired a special
status in the design of receptors because it displays dual
0
dium salts of N,N -ditosyl-bis-(2-aminoethyl)sulfide with
polyethylene glycol ditosylates [19] or a per-N-tosyl di-thia
tetramine with 1,2-ethanediyl ditosylate using cesium
carbonate in DMF [20]. Other suitable intramolecular
cyclization method was used by Okahara to synthesis
substituted sulfur containing macrocycles [21].
As, generally in the crab like synthetic method the
high dilution technique is not required, the use of bis(a-
chloroacetamide) is an important step in macrocyclization
process [15,22]. Also, because the aromatic amine nitro-
gens are moderately active nucleophiles, generally the
(
O or N and NH) ligating character, higher negative charge
on oxygen than for ether and ester groups, and geometrical
rigidity [6]. The averaged effects of these factors were
found also in our researches on the complexation of
aza-thia macrocyclic diamides with varieties of transition
metal ions [7]. Amide-based macrocycles for selective
recognition of metal cations [2,8] and organic molecules
[2,3] typically adopt preorganization of their binding sites
through hydrogen bonding or configurational rigidity
around the amide carbon-nitrogen bond.
©
2012 HeteroCorporation

5
00
A. Shockravi and M. Kamali
Vol 49
Scheme 1
1
azamacrocycles were prepared by corresponding bis(a-
chloroactamide)s substrats, which are converted to electro-
philic moieties with relatively good leaving group.
The crab like cyclization using the bis-a-chloroaceta-
midediphenylsulfide (BCADPS) (3) was used to synthesis
the aza macrocycles (4–9). The formation of two C—N
bonds in the ring closure step was performed by diacylation
of diamines (2) using a-chloroacetylchloride.
We have previously prepared a series of macrocyclic
compounds based on dibenzosulfide, dinaphthosulfide
containing hydroxyl phenolic groups and studied their
metal ion complexations [7,16]. In this work, we wish
to report the synthesis of six aza-thia and oxa macro-
cycles (4–8) using the reaction of BCADPS (3) as crab-
like condensing reagent with different diamines (a–e)
All products were identified using IR, H-NMR,
1
3
C-NMR, and mass spectroscopies. All macrocycles
were obtained as [1 + 1] condensation products except
when diamine (e) was used in which both [1 + 1] and
[1 + 2] products were synthesized. The formation of
[1 + 2] product as cryptand (9) may be attributed to the
template of effect of potassium ion (K ) which appar-
ently its ionic radius was more proper for such macro-
cyclization reaction conditions.
+
Scheme 2
(Scheme 2) and the synthesis of cryptand (9) as the only
[1 + 2] condensation product.
RESULTS AND DISCUSSION
In this work, diamine diphenyl sulfide (2) [23] was
obtained from the reduction of corresponding dinitro com-
pound (1) which its reaction with chloroacetyl chloride
at room temperature led to BCADPS (3) in 4 h. High
dilution technique and template effect of potassium ion
were most effective conditions for the synthesis of macro-
cycles (4–9) in moderate to good yields and short time (5
h). (Scheme 1 and Table 1)
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

0
May 2012
Synthesis of New Aza Macrocyclic Diamides 2,2 -Diaminodiphenyl
501
Sulfide Using Crab-Like Method
Table 1
(10 mmol, 2.16 g) and triethylamine (22 mmol, 3 mL) in CH Cl2
2
(
80 mL), chloroacetylchloride (1.75 mL, 22 mmol) in 1 h was
Macrocycles (4–9) and cryptand (9).
added and stirred 3 h at room temperature. After completion of
the reaction (TLC), the mixture washed with solution of HCl
Z
Products
1
0% (3ꢀ 40) and organic layer evaporated to afford a precipitate
a
b
c
d
e
—(CH
—CH
2
)
2
—
4
5
6
7
8, 9
which was recrystallized from ethanol to give pure diamine (2)
in the quantitative yield. Mp 152–153 C; IR (KBr): 3925, 3263,
3
2
—(*CH)CH
3
—
ꢁ
—(CH
—(CH
O(CH
2
2
2
)
3
)
4
)
2
—
—
O(CH
ꢂ1
1
176, 1669, 1590, 1579, 1537, 1436, 768, 659 cm ; H-NMR
(
300 MHz, CDCl ); d 4.17 (s, 4H), 7.09–7.15 (t, 2H, J = 7.8 Hz),
3
—(CH
2
)
2
2
)
2
—
7
8
.23–7.26 (d, 2H, J = 9.0 Hz), 7.33–7.38 (t, 2H, J = 7.8 Hz),
.13–8.16 (d, 2H, J = 9.0 Hz), 8.98 (s, 2H, exchanged with D O)
2
13
Interestingly, the diastereotopicity character was found
in the cryptand (9) which could be because of the rigidity
of the cryptand structure. The dioxy triethylene bridge
has also decreased the flexibility of the cryptand signifi-
cantly which in turn participates in the diastereotopicity
ppm; C-NMR (300 MHz, CDCl
26.15, 129.45, 132.69, 136.42, 164.24 ppm; Anal. Calcd. for
S: C, 52.04; H, 3.82; N, 7.59. Found: C, 52.31;
3
); d 43.08, 122.67, 124.06,
1
16 2 2 2
C H14Cl N O
H, 3.84; N, 7.53.
General procedure for the synthesis of bis acetamide-
+
diphenylsulfide aza macrocycles. To 2 mmol of compound
character. It seems that potassium ion’s (K ) template ef-
(
2 3
2) in acetonitrile (100 mL), K CO (2 mmol, 0.276 g), KI (0.1
fect was effective in the formation of the cryptand espe-
cially due to oxygen donor atoms in the bridge between
two nitrogen atoms. Identification of this cryptand was
made by different spectroscopic means.
mmol, 0.017 g), and the appropriate diamine (2 mmol) were
added, then mixture was refluxed for 5 h. On completion of the
reaction (TLC), the reaction mixture was allowed to cool to
room temperature, and precipitate isolated with filtering, then
the filtrate was evaporated under reduced pressure and
respective crown was isolated by column chromatography on
silica gel 60 using solvent mixed ethyl acetate and methanol
1
The H-NMR spectrum of cryptand (9) showed one trip-
let at d 2.63 ppm (4H) for two methylenes (25, 32) which
are linked with nitrogen atoms. Two diasterotopic methy-
lene hydrogens (6, 8, 18, 20) are appeared as two doublets
at 3.17–3.23 ppm (4H, J= 17.3 Hz) and 3.42–3.48 ppm
4H, J= 17.3 Hz), respectively. One triplet appeared at d
.31ppm (4H) for two methylene hydrogens (26, 31) which
are linked with oxygen atoms. One sharp singlet is ob-
served at d 3.38 ppm for four isochronous methylene
hydrogens (28, 29) and 12 hydrogen atoms aromatic at
.97–7.75 ppm (Scheme 2). Such diastereotopic evidences
were not found in other macrocycles (4–8) which is due to
their flexible cavities. For example, H-NMR macrocycle
4) showed one sharp singlet for two methylenes (8, 9)
linked with NH amines (d 2.75 ppm, 4H) and one sharp
singlet for two methylenes (6, 11) linked with carbonyl
groups (d 3.28 ppm, 4H) and 8H aromatic (d 7.05–8.25
ppm, 8H) (Scheme 3).
(
90:10).
Synthesis of 4,7,10,13-tetraaza-1-thia-2,3;14,15-dibenzo
cyclopentadecane-5,12-dione (4). This macrocycle was
(
3
synthesized based on the general procedure involving the
reaction of compound 3 (2 mmol, 0.92 g), and ethylenediamine
(2 mmol, 0.14 mL) in refluxing acetonitrile (100 mL). The solid
product was purified using column chromatography to afford 4
ꢁ
as a white solid in 76% yield, mp 211–213 C; IR (KBr): 3325,
ꢂ1
3
296, 3232, 3164, 1671, 1585, 1572, 1517, 758 cm
;
6
1
H-NMR (300 MHz, CD CN); d 2.1 (s, 2H, exchanged with
3
D O), 2.75 (s, 4H), 3.28 (s, 4H), 7.05–7.10 (t, 2H, J = 7.8 Hz),
1
2
7
8
.31–7.36 (t, 2H, J = 8.1 Hz), 7.42–7.45 (d, 2H, J = 7.8 Hz),
.21–8.25 (d, 2H, J = 8.1 Hz), 10.57 (s, 2H, exchanged with
(
13
2 3
D O, NH) ppm; C-NMR (300 MHz, CD CN); d 49.73, 53.23,
117.24, 120.92, 124.19, 129.39, 134.24, 138.16, 170.50 ppm;
ms (electron impact) m/z: (M , molecular ion) 356, 261, 243,
2
+
16, 199, 161, 140, 124, 85, 44.
Scheme 3
EXPERIMENTAL
Chemicals and apparatus. All reactions were carried out
in an efficient hood. The starting materials were purchased from
Merck and fluka chemical companies. Column chromatography
was performed on silica gel 60 (0.04–0.063 mm). Melting
points were determined with a Branstead Electrothermal model
9
200 apparatus and are uncorrected. IR spectra were recorded
on Perkin Elmer RX13 Fourier transform infrared
spectrometer. The H- and C-NMR spectra were recorded in
DMSO-d and CDCl on Bruker Avance 300 MHz
a
1
1
6
3
spectrometers. Elemental analyses were carried out by a Perkin
Elmer 2400 series II CHN/O analyzer. Mass spectra were
obtained by an electron ionization Varian Incos 50 and
JOELJMS-700 and the MuLDI spectra BRUKER Biflex.
0
Synthesis of 2,2 -sulfanyl-bis(-a-chloroacetanilide) (3). To
0
a
solution of the appropriate 2,2 -daminodiphenyl sulfide
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

5
02
A. Shockravi and M. Kamali
Vol 49
Synthesis of 4,7,10,13-tetraaza-1-thia-8-methyl-2,3;14,15-
Macrocycle 4,7,16,19-tetraaza-10,13-oxa-1-thia-2,3;20,21-
dibenzo cyclopenta decane-5,13-dione (5). This macrocycle
was synthesized based on the reaction of compound 3 (2 mmol,
dibenzo cyclodocosane-5,18-dione (8).
3224, 3057, 1679,1576, 1512, 763 cm ; H-NMR (300 MHz,
IR (KBr): 3357,
ꢂ1
1
0
.92 g), and 1-methyl-1,2-diaminopropane (optical active)
6
DMSO-d ); d 2.61–2.64 (t, 4H, J = 4.5 Hz), 3.41–3.44 (t, 4H, J =
(
2 mmol, 0.18 mL) in refluxing acetonitrile (100 mL). The solid
4.5 Hz), 3.47 (s, 4H), 3.95 (s, 4H), 7.01–7.04 (d, 2H, J = 7.5 Hz),
7.07–7.12 (t, 2H, J = 7.2 Hz), 7.29–7.34 (t, 2H, J = 7.8 Hz),
7.86–7.89 (d, 1H, J = 8.0 Hz), 7.91–7.94 (d, 1H, J = 8.0 Hz), 9.98
product was purified using column chromatography to afford
ꢁ
5
3
7
as a white solid in 70% yield, mp 267–269 C; IR (KBr):
13
435, 3354, 3304, 3232, 3155, 1671, 1586, 1573, 1514, 773,
2 6
(s, exchanged with D O) ppm; C-NMR (300 MHz, DMSO-d ); d
ꢂ1
1
57 cm ; H-NMR (300 MHz, DMSO-d
6
); d 0.99–1.01 (d, 3H,
49.09, 52.59, 70.14, 70.41, 123.62, 125.75, 126.43, 129.47, 132.37,
+
J = 6.1 Hz), 2.58 (d, 2H, J = 6.1 Hz), 2.67 (m, 1H), 3.07–3.09
137.54, 171.06 ppm; ms (electron impact) m/z: (M , molecular ion)
(
(
d, 1H, J = 7.7 Hz), 3.13–3.15 (d, 1H, J = 7.7 Hz), 3.31–3.32
d, 1 H, J = 17.4 Hz), 3.35–3.38 (d, 1H, J = 17.4 Hz), 3.33 (s,
445, 199, 93, 42.
Macrocycle 4,7,10,16,20,22-hexaaza-10,13-dithia-27,30-di
2
(
H, exchanged with D
2t, 2H), 7.36–7.38(d, 1H, J = 7.8 Hz), 7.42–7.45 (d, H,
J = 8.1 Hz), 8.08–8.10 (d, 1H, J = 8.1 Hz), 8.18–8.20 (d, 1H,
2
O, NH), 7.08–7.13 (tb, 2H), 7.32–7.38
oxa-3,2;11,12;17,18;-20,21-tetrabenzo
bicycle[11,11,8]
triacontane-5,9,17,21-tetraone (9). IR (KBr): 3460, 3248,
ꢂ1
1
3057, 1735, 1686, 1576, 1508, 752 cm ; H-NMR (300 MHz,
1
3
J = 8.1 Hz), 10.64 (s, exchange with D O) ppm; C-NMR
DMSO-d ); d 2.63 (tb, 4H), 3.17–3.23 (d, 4H, J = 17.3 Hz),
2
6
(
1
1
300 MHz, DMSO-d
6
); d 17.86, 50.67, 53.36, 53.84, 55.98,
20.66, 121.56, 123.06, 123.84, 124.33, 124.62, 129.37,
29.61, 134.03, 134.46, 137.77, 137.96, 170.62, 171.04 ppm;
3.31 (tb, 4H), 3.38 (s, 4H), 3.42–3.48 (d, 4H, J = 17.3 Hz),
6.97–7.00 (d, 4H, J = 7.5 Hz), 7.07–7.12 (t, 4H, J = 7.5 Hz),
7.25–7.30 (t, 4H, J = 7.8 Hz), 7.73–7.75 (d, 2H, J = 7.8 Hz),
+
13
ms (electron impact) m/z: (M , molecular ion) 371, 216, 199,
83, 154, 124, 93, 56.
Synthesis 4,7,11,14-tetraaza-1-thia-2,3;15,16-dibenzo
cyclohexadecane-5,14-dione (6). This macrocycle was
9.82 (s, 4H, exchanged with D O) ppm; C-NMR (300 MHz,
2
1
DMSO-d ); d 55.46, 59.35, 69.41, 70.42, 124.87, 126.55,
6
1
26.74, 129.18, 131.87, 137.20, 170.62 ppm; ms (electron
+
impact) m/z: (M , molecular ion) 741, 216, 199, 173, 136, 120,
3, 74, 56.
9
synthesized based on the reaction of compound 3 (2 mmol, 0.92
g), and 1,3-diaminopropane (2 mmol, 0.17 mL) in refluxing
acetonitrile (100 mL). The solid product was purified using
column chromatography to afford 6 as a white solid in 69%
yield, mp 192–195 C; IR (KBr): 3357, 3332, 3291, 3250, 1663,
1
Acknowledgment. We thank the research council of the Tarbiat
Moallem University for financial support.
ꢁ
ꢂ1
1
584, 1571, 1507, 763 cm
3
; H-NMR (300 MHz, CD CN);
d 1.66–1.70 (m, 2H), 2.5 (s, 2H, exchange with D O, NH),
2
2
.81–2.85 (t, 4H, J = 6.0 Hz), 3.25 (s, 4H), 7.06–7.11 (t, 2H,
REFERENCES AND NOTES
J = 7.6 Hz), 7.28–7.34 (m, 4H), 7.97–8.00 (2d, 2H, J = 8.7 Hz),
1
3
[1] Pedersen, C. J. J Am Chem Soc 1967, 89, 7017.
9
2
.96 (s, exchanged with D O) ppm; C-NMR (300 MHz,
[
2] Izatt, R. M.; Pawlak, K.; Bradshaw, J. S.; Bruening, R. L.
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CD CN); d 29.36, 46.69, 60.91, 117.32, 122.05, 125.23, 129.80,
3
1
33.35, 137.68, 170.81 ppm; ms (electron impact) m/z (relative
[
+
intensity %): (M , molecular ion) 371, 243, 216, 199, 183, 154,
2
2
1
24, 106, 85, 44.
Synthesis
cycloheptadecane-5,15-dione (7).
4,7,12,15-tetraaza-1-thia-2,3;15,16-dibenzo
This macrocycle was
M.; Buschel, M.; Tolmachev, A. I.; Daub, J.; Rurack, K. J Am Chem Soc
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2
synthesized based on the reaction of compound 3 (2 mmol, 0.92 g),
and 1,4-diaminobutane (2 mmol, 0.2 mL) in refluxing acetonitrile
(
100 mL). The solid product was purified using column
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2
1
ꢁ
06–207 C; IR (KBr): 3441, 3354, 3243, 3189, 1690, 1674,
ꢂ1
1
586, 1575, 1519, 761 cm ; H-NMR (300 MHz, DMSO-d );
6
[7] (a) Shockravi, A.; Shamsipur, M.; Fattahi, H.; Taghdiri, M.;
d 1.61 (t, 4H, J = 8.5 Hz), 2.54 (t, 4H, J = 8.5 Hz), 3.20 (s, 4H),
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3
7
8
2
.32 (2H, exchanged with D O), 7.03–7.08 (t, 2H, J = 7.7 Hz),
.10–7.13 (d, 2H, J = 7.7 Hz), 7.33–7.38 (t, 2H, J = 8.2 Hz),
.33–8.35 (d, 2H, J = 8.2 Hz), 10.27 (s, exchanged with D O)
2
13
ppm; C-NMR (300 MHz, DMSO-d ); d 27.54, 49.63, 53.32,
1
ms (electron impact) m/z: (M , molecular ion) 385, 243, 199,
1
6
21.33, 121.92, 125.44, 129.33, 131.62, 137.06, 171.55 ppm;
+
[8] Freiria, A.; Bastida, R.; del Carmen Fernandez-Fernandez, M.;
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28, 84, 43.
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Chem 1992, 27, 201.
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acetonitrile (100 mL). The solid product was purified using
column chromatography to afford 9 as a white solid in 66%
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Chem 1985, 50, 5469; (b) Ninagawa, A.; Maeda, T.; Matsuda, H.
ꢁ
yield, with mp 276–280 C and white solid 10 yield 15%, with mp
[
ꢁ
1
69–170 C. These macrocycles were characterized as following.
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

0
May 2012
Synthesis of New Aza Macrocyclic Diamides 2,2 -Diaminodiphenyl
503
Sulfide Using Crab-Like Method
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Journal of Heterocyclic Chemistry
DOI 10.1002/jhet