Synthesis of 4-(4-oxo-1,3-thiazolidin-2-ylidene)-pyrrolidine-2,3,5-triones

Article abstract of DOI:10.1007/s10593-017-2102-0

[Figure not available: see fulltext.] It was shown that 2-(1,3-thiazolidin-2-ylidene)acetamides can be used as 2-enamides in cyclocondensation reactions with oxalyl chloride, leading to the formation of new heterocyclic assemblies – 4-(4-oxo-1,3-thiazolid

Full text of DOI:10.1007/s10593-017-2102-0

DOI 10.1007/s10593-017-2102-0
Chemistry of Heterocyclic Compounds 2017, 53(5), 622–625
Synthesis of 4-(4-oxo-1,3-thiazolidin-2-ylidene)-
pyrrolidine-2,3,5-triones
Konstantin L. Obydennov1*, Aleksei N. Galushchinskiy1,
Marya F. Kosterina1, Tatiana V. Glukhareva1, Yuri Yu. Morzherin1†
1 Ural Federal University named after the first President of Russia B. N. Yeltsin,
19 Mir St., Yekaterinburg 620002, Russia; е-mail: k.l.obydennov@urfu.ru
Submitted January 26, 2017
Accepted February 14, 2017
Translated from Khimiya Geterotsiklicheskikh Soedinenii,
2017, 53(5), 622–625
It was shown that 2-(1,3-thiazolidin-2-ylidene)acetamides can be used as 2-enamides in cyclocondensation reactions with oxalyl
chloride, leading to the formation of new heterocyclic assemblies – 4-(4-oxo-1,3-thiazolidin-2-ylidene)pyrrolidine-2,3,5-triones in 50–
88% yields.
Keywords: oxalyl chloride, pyrrolidine-2,3,5-trione, thiazolidin-4-one, cyclocondensation, exocyclic double bond, heterocyclic
assemblies.
Molecular assemblies derived from 1,3-thiazolidin-4-one
ring connected by exocyclic С=С double bond to other five-
membered heterocycles attract the attention of researchers
due to their biological effects (such as antimalarial1 and
anticancer2 activity), as well as by their electrochemical3,4 and
photophysical properties.5,6 Among compounds of this type
the most often reported in the literature are (1,3-thiazo-
lidinylidene)-1,3-thiazolidines7 and (2-oxoindolin-3-ylidene)-
1,3-thiazolidin-4-ones.8 Some examples of molecular
assemblies have been described where the 1,3-thiazolidine
ring is linked through a С=С bond with pyrazole,9
oxazole,10 and other heterocycles. At the same time,
molecular assemblies of 1,3-thiazolidine and pyrrolidine-
2,3,5-one have not been described in the literature at all.
In this work, we propose a convenient method for the
synthesis of new heterocyclic assemblies – 4-(4-oxo-1,3-
thiazolidin-2-ylidene)pyrrolidine-2,3,5-triones by cyclo-
condensation of 2-(1,3-thiazolidin-2-ylidene)acetamides
with oxalyl chloride.
The starting 2-(1,3-thiazolidin-2-ylidene)acetamides 1a–e
were synthesized in 53–85% yields by reacting the res-
pective nitriles 2a–e with mercaptoacetic acid (Scheme 1,
Table 1) upon heating for 12 h in pyridine in the presence
of p-dimethylaminopyridine (DMAP). Despite the fact that
this method for the synthesis of 1,3-thiazolidin-
_______________________________________________
† Deceased
4-one derivatives is widely reported in the literature,11–15
1,3-thiazolidines 1a,b,d,e have not been described
previously. Synthetic procedure optimization for the
preparation of previously described15 compound 1с allowed
to increase its yield from 60%15 to 85%.
Based on the chemical shift of the 2'-CH methine proton
1
signal (5.55–5.82 ppm) in H NMR spectra of compounds
1a–e and taking into account the literature data,16 we
assigned (Z)-configuration to the exocyclic С=С double bond.
2-(1,3-Thiazolidin-2-ylidene)acetamides 1 have been
previously studied in alkylation,17 bromination,18,19
thionation,20 cyclocondensation,21 and Claisen condensation22
reactions. However, their interaction with such bis-
electrophile as oxalyl chloride has not been described in the
literature. At the same time, it is known that the reactions
of oxalyl chloride with 2-enamides as bisnucleophiles led
to the formation of pyrrolidine-2,3,5-triones.23–25
As a result of reaction between 1,3-thiazolidines 1a–d
and oxalyl chloride at 0–5°С in anhydrous THF, we
synthesized 4-(4-oxo-1,3-thiazolidin-2-ylidene)pyrrolidine-
2,3,5-triones 3a–d in 82–88% yields (Scheme 1, Table 1).
It should be noted that, due to the low reactivity of 1,3-
thiazolidine 1e containing a p-nitrophenyl moiety, the
reaction with oxalyl chloride proceeded in MeCN upon
heating to 80°С for 0.5 h. However, product 3е could not
be isolated as individual compound and purified, as it was
unstable in solution.
0009-3122/17/53(05)-0622©2017 Springer Science+Business Media New York
622

Chemistry of Heterocyclic Compounds 2017, 53(5), 622–625
Scheme 2
Scheme 1
O
HS
CO2H
O
NH
R
S
DMAP, Py
R
N
H
CN
2
2'
, 12 h
N
H
O
2a–e
1a–e
O
Cl
Cl
O
O
O
THF
R
S
0_5°C 5 h
N
for 1e
MeCN
80°C 0 5 h
N
H
3a–e
O
O
1585 cm−1 were also observed for compounds 1b–e and 3b–d
(R = Bn, Ar), but reliable assignment of these absorptions
was impossible due to the presence of benzene rings in the
structure, which also produced absorption in this range.
Thus, in the current work we propose a convenient
method for the synthesis of new molecular assemblies
containing 1,3-thiazolidin-4-one and pyrrolidine-2,4,5-
trione rings, and note that these compounds in solution
phase exist in equilibrium with their isomeric forms that
arise due to rotation around the exocyclic С=С bond with a
partial double bond character.
Table 1. Yields of thiazolidines 1a–e and 3a–e
R
Compound
Yield, %
Compound
Yield, %
Me
Bn
53
61
85
72
71
86
88
1a
1b
1c
1d
1e
3a
3b
3c
3d
3e
Ph
82
4-MeOC6H4
4-O2NC6H4
85
50*
* According to 1H NMR spectroscopy data, the content of the target
compound was 85%.
Experimental
IR spectra were recorded on a Bruker ALPHA
spectrometer that was equipped with a ZnSe ATR
All of the molecular assemblies 3a–d showed [M]+
peaks of the molecular ion in their mass spectra. The
characteristic fragment ion peaks were [M−СO]+,
1
accessory. Н and 13С NMR spectra were acquired on a
Вruker Avance II spectrometer (400 and 100 MHz,
respectively) in DMSO-d6 (an additional 1H NMR spectrum
for compound 3a was acquired in DMF-d6) at the Laboratory
of Complex Investigation and Expert Evaluation of Organic
Materials at the Collective Use Center of the Ural Federal
University. TMS was used as internal standard. 1Н and
13С NMR spectra of compounds 3a–d were acquired
immediately after dissolution of samples because of their
instability in solution. Mass spectra were recorded on a
Shimadzu GCMS-QP2010 Plus gas chromato-mass
spectrometer (EI ionization, 70 eV). Elemental analysis was
performed on a РЕ 2400 Series II CHNS-analyzer. Melting
points were determined on a Stuart SMP3 apparatus.
1
[M−С2O2H]+, and [M−СO−С2O2H]+. H NMR spectra of
compounds 3a–d in DMSO-d6 solution showed a single set
of signals for all protons, except for the methylene group in
the thiazolidine ring, which gave two broadened singlets in
the range of 3.99–4.02 ppm.26 Additional studies showed
doubling of methylene, methyl, and NH group signals in
1H NMR spectra of compound 3a that were recorded in
DMF-d6 solution at −18°С. This phenomenon can be
explained by hindered rotation around the exocyclic С=С
bond that had a partial double bond nature, with the
rotation slowing down at lower temperature. A decrease in
the order of the exocyclic double bond in molecular
assemblies 3a–d was possible due to its push-pull character
and ketone-enol tautomerism (Scheme 2).27 The analysis of
1H NMR spectra obtained for the molecular assembly 3a in
DMF-d6 solution at the temperature range from −18 to 28°С
enabled an approximate estimate of the coalescence
temperature as 0°С (see the Supplementary information
file).
Preparation of 2-(4-oxo-1,3-thiazolidin-2-ylidene)-
acetamides 1a–e (General method). Pyridine was added
dropwise with stirring to cyanoacetamide 2a–e (15 mmol)
in a round-bottom flask until complete dissolution of the
cyanoacetamide. DMAP (18 mg, 0.15 mmol) and
mercaptoacetic acid (3.2 ml, 46 mmol) were added to the
obtained solution. The obtained mixture was refluxed for
12 h in a flask equipped with a reflux condenser, then
diluted with 0.5 М HCl solution (5 ml). The precipitate of
1,3-thiazolidinone 1 was filtered off and washed with hot
MeCN (15 ml). When necessary, the product was
1
It was also shown that H NMR spectrum of compound
3a in DMSO solution, which was acquired at 30°С, showed
coalescence of methylene proton signals that could be
explained by the faster rotation of rings around the
exocyclic bond.
additionally purified by refluxing
a suspension of
IR spectra of compounds 1a and 3a (R = Me) featured
absorption bands at 1556 and 1574 cm−1, respectively. This
observation pointed to the presence of С=С double bond in
their structure.28 Absorption bands in the range of 1540–
thiazolidine in MeCN, followed by hot filtration.
(2Z)-N-Methyl-2-(4-oxo-1,3-thiazolidin-2-ylidene)acet-
amide (1a). Yield 1.37 g (53%), white powder, mp 238–
243°С (decomp.). IR spectrum, ν, cm−1: 1184, 1299, 1398,
623

Chemistry of Heterocyclic Compounds 2017, 53(5), 622–625
1415, 1470, 1556 (C=С), 1624 (C=O), 1699 (C=O), 3312
after 2 min. The obtained suspension was stirred at the
same temperature for 5 h, then a 1:4 mixture of H2O–THF
(1 ml) was gradually added to the reaction mixture until the
evolution of bubbles ceased. Cold water (2 ml) was then
added, the precipitate was filtered off and washed with Et2O.
1-Methyl-4-(4-oxo-1,3-thiazolidin-2-ylidene)pyrrolidine-
2,3,5-trione (3a). Yield 78 mg (86%), white powder,
mp 246–250°С (decomp.). IR spectrum, ν, cm−1: 1026,
1150, 1235, 1327, 1559, 1574 (C=С), 1670 (C=O), 1713
1
(NH). H NMR spectrum, δ, ppm (J, Hz): 2.58 (3H, d,
J = 4.8, CH3); 3.61 (2H, s, CH2); 5.55 (1H, s, CH); 7.61
(1H, br. s, NH); 11.20 (1H, s, NH). 13C NMR spectrum,
δ, ppm: 25.3; 31.9; 92.4; 151.4; 167.0; 174.0. Mass
spectrum, m/z (Irel, %): 172 [М]+ (94), 142 [М−NHCH3]+
(100), 114 [М−NHCH3−CO]+ (55), 98 (30), 86 (37), 68
(78), 42 (35), 40 (22). Found, %: C 41.70; H 4.61; N 16.51.
C6H8N2O2S. Calculated, %: C 41.85; H 4.68; N 16.27.
(2Z)-N-Benzyl-2-(4-oxo-1,3-thiazolidin-2-ylidene)acet-
amide (1b). Yield 2.27 g (61%), white powder, mp 208–
209°С. IR spectrum, ν, cm−1: 1301, 1539 (C=С), 1629
(C=O), 1701 (C=O), 2782, 2882, 3059, 3304 (NH).
1H NMR spectrum, δ, ppm (J, Hz): 3.54 (2H, s, CH2); 4.28
(2H, d, J = 6.0, NСH2); 5.63 (1H, s, CH); 7.16–7.31 (5H,
m, H Ph); 8.05 (1H, t, J = 6.0, NH); 11.19 (1H, s, NH).
13C NMR spectrum, δ, ppm: 31.8; 41.8; 92.2; 126.5; 127.1;
128.1; 139.9; 152.0; 166.4; 173.8. Mass spectrum, m/z (Irel, %):
248 [М]+ (59), 142 [М−NHBn]+ (20), 115 [М−NHBn−CO+H]+
(15), 106 (100), 91 (79), 77 (10), 68 (24). Found, %:
C 58.27; H 4.82; N 11.33. C12H12N2O2S. Calculated, %:
C 58.05; H 4.87; N 11.28.
1
(C=O), 1739 (C=O), 1763 (C=O), 3219 (NH). H NMR
spectrum (DMSO-d6), δ, ppm: 3.03 (3H, s, CH3); 4.00 (1H,
1
s) and 4.02 (1H, s, СH2); 11.69 (1H, br. s, NH). H NMR
spectrum (DMF-d6), δ, ppm: 3.05 (3H, s, CH3); 4.19 (2H, s,
СH2); 11.87 (1H, br. s, NH). 13C NMR spectrum, δ, ppm:
23.4; 32.1; 96.5; 162.3 (2C); 167.2; 175.0 (2C). Mass
spectrum, m/z (Irel, %): 226 [М]+ (55), 198 [М−CO]+ (1),
169 [М−C2O2H]+ (32), 141 [М−C2O2H−CO]+ (100), 99
(14), 71 (12), 68 (47), 46 (35). Found, %: C 42.32; H 2.68;
N 12.22. C8H6N2O4S. Calculated, %: C 42.48; H 2.67;
N 12.38.
1-Benzyl-4-(4-oxo-1,3-thiazolidin-2-ylidene)pyrrolidine-
2,3,5-trione (3b). Yield 106 mg (88%), light-green powder,
mp 232–236°С (decomp.). IR spectrum, ν, cm−1: 1238, 1328,
1389, 1568 (C=С), 1674 (C=O), 1712 (C=O), 1761 (C=O),
(2Z)-2-(4-Oxo-1,3-thiazolidin-2-ylidene)-N-phenylacet-
amide (1c).29 Yield 2.99 g (85%), white powder, mp 282–
285°С (mp 287–289°С29).
1
3219 (NH). H NMR spectrum, δ, ppm: 4.02 (1H, s) and
(2Z)-N-(4-Methoxyphenyl)-2-(4-oxo-1,3-thiazolidin-2-yl-
idene)acetamide (1d). Yield 2.85 g (72%), white powder,
mp 261–263°С. IR spectrum, ν, cm−1: 1156, 1316, 1413,
1455, 1508, 1547, 1574, 1604, 1647 (C=O), 1696 (C=O),
2834, 2903, 2962, 2994, 3068, 3131, 3172, 3237, 3274
4.04 (1H, s, СH2); 4.72 (2H, s, NСH2); 7.23–7.38 (5H, m,
H Ph); 11.82 (1H, br. s, NH). 13C NMR spectrum, δ, ppm:
32.1; 40.7; 96.3; 127.3; 127.4; 128.4; 136.1; 161.9 (2C);
168.0; 174.8 (2С). Mass spectrum, m/z (Irel, %): 302 [М]+
(100), 274 [М−CO]+ (11), 245 [М−C2O2H]+ (12), 211 (19),
186 (10), 171 (15), 141 [М−C2O2NHCH2C6H5+H]+ (88),
106 (42), 91 (96), 70 (27), 68 (43), 46 (32), 39 (17). Found,
%: C 55.85; H 3.15; N 9.32. C14H10N2O4S. Calculated, %:
C 55.62; H 3.33; N 9.27.
1
(NH), 3295. H NMR spectrum, δ, ppm (J, Hz): 3.60 (2H,
s, CH2); 3.74 (3H, s, CH3); 5.76 (1H, s, CH); 6.78 (2Н, d,
J = 9.0, H Ar); 7.50 (2Н, d, J = 9.0, H Ar); 9.51 (1H, s,
NH); 11.35 (1H, s, NH). 13C NMR spectrum, δ, ppm: 32.0;
55.1; 92.6; 113.8; 120.0; 133.0; 153.5; 154.7; 164.9; 174.1.
Mass spectrum, m/z (Irel, %): 264 [М]+ (9), 142
[М−NHC6H4OCH3]+ (7), 123 (100), 108 (48), 68 (15).
Found, %: C 54.30; H 4.69; N 10.71. C12H12N2O3S.
Calculated, %: C 54.53; H 4.58; N 10.60.
4-(4-Oxo-1,3-thiazolidin-2-ylidene)-1-phenylpyrrolidine-
2,3,5-trione (3c). Yield 95 mg (82%), white powder,
mp 267–272°С (decomp.). IR spectrum, ν, cm−1: 1138,
1216, 1399, 1496, 1573 (C=С), 1678 (C=O), 1719 (C=O),
1746 (C=O), 1787 (C=O), 2932, 2982, 3190 (NH).
1H NMR spectrum, δ, ppm (J, Hz): 4.04 (1H, s) and 4.06
(1H, s, СH2); 7.34–7.43 (3H, m, H Ph); 7.49 (2H, dd,
J = 7.5, J = 7.5, H Ph); 11.84 (1H, br. s, NH). 13C NMR
spectrum, δ, ppm: 32.3; 96.4; 126.9; 128.2; 128.8; 131.5;
161.2 (2C); 168.7; 175.3 (2C). Mass spectrum, m/z (Irel, %):
(2Z)-N-(4-Nitrophenyl)-2-(4-oxo-1,3-thiazolidin-2-yl-
idene)acetamide (1e). Yield 2.97 g (71%), yellow powder,
mp 252–260°С (decomp.). IR spectrum, ν, cm−1: 1106,
1136, 1256, 1306, 1323 (NO2), 1406, 1498, 1529, 1543,
1581 (NO2), 1679 (C=O), 1707 (C=O), 2818, 2898, 3009,
3066, 3109, 3366 (NH). 1H NMR spectrum, δ, ppm
(J, Hz): 3.64 (2H, s, CH2); 5.82 (1H, s, CH); 7.83 (2Н, d,
J = 9.2, H Ar); 8.10 (2Н, d, J = 9.2, H Ar); 10.28 (1H, s,
NH); 11.57 (1H, s, NH). 13C NMR spectrum, δ, ppm
(J, Hz): 32.2; 91.9; 118.0; 125.0; 141.4; 146.2; 157.0;
165.8; 174.3. Mass spectrum, m/z (Irel, %): 280 [М+H]+ (2),
279 [М]+ (15), 142 [М−NHC6H4NO2]+ (100), 138 (44),
114 [М−NHC6H4NO2−CO]+ (36), 108 (13), 86 (25), 68
(68). Found, %: C 47.39; H 3.46; N 15.21. C11H9N3O4S.
Calculated, %: C 47.31; H 3.25; N 15.05.
288
[М]+
(31),
260
[М−CO]+
(27),
141
[М−C2O2NHC6H5+H]+ (100), 119 (54), 99 (11), 91 (24),
77 (10), 68 (35), 46 (24). Found, %: C 54.11; H 2.74;
N 9.83. C13H8N2O4S. Calculated, %: C 54.16; H 2.80;
N 9.72.
1-(4-Methoxyphenyl)-4-(4-oxo-1,3-thiazolidin-2-ylidene)-
pyrrolidine-2,3,5-trione (3d). Yield 108 mg (85%), light-
green powder, mp 235–240°С (decomp.). IR spectrum,
ν, cm−1: 1145, 1163, 1211, 1242, 1253, 1299, 1330, 1392,
1405, 1441, 1468, 1512, 1568 (C=С), 1679 (C=O), 1715
(C=O), 1766 (C=O), 2834, 2955, 3012, 3212 (NH).
1H NMR spectrum, δ, ppm (J, Hz): 3.82 (3H, s, CH3); 4.05
(2H, s, CH2); 6.99 (2Н, d, J = 8.0, H Ar); 7.25 (2Н, d,
J = 8.0, H Ar); 11.78 (1H, br. s, NH). 13C NMR spectrum,
δ, ppm: 32.3; 55.4; 96.4; 114.0; 123.9; 128.2; 158.9; 161.4
Preparation of 4-(4-oxo-1,3-thiazolidin-2-ylidene)-
pyrrolidine-2,3,5-triones
3a–e
(General method).
Anhydrous THF (2 ml) was cooled in ice bath and oxalyl
chloride (41 μl, 0.48 mmol) was dissolved in it with stirr-
ing, followed by the addition of thiazolidine 1a–d (0.4 mmol)
624

Chemistry of Heterocyclic Compounds 2017, 53(5), 622–625
8. Gazieva, G. A.; Izmest'ev, A. N. Chem. Heterocycl. Compd.
(2C); 168.3; 175.2 (2C). Mass spectrum, m/z (Irel, %): 318
[М]+ (19), 290 [М−CO]+ (9), 149 (100), 134 (29), 106 (13).
Found, %: C 52.68; H 2.96; N 8.69. C14H10N2O5S.
Calculated, %: C 52.83; H 3.17; N 8.80.
1-(4-Nitrophenyl)-4-(4-oxo-1,3-thiazolidin-2-ylidene)-
pyrrolidine-2,3,5-trione (3e) was obtained according to the
general procedure from thiazolidine 1e (0.12 g, 0.4 mmol)
in anhydrous MeCN, by heating the suspension for 30 min
at 80°С. The mixture was treated with 1:4 mixture of H2O–
MeCN (1 ml). Yield 67 mg (50%), light-yellow powder,
mp 260–285°С (decomp.). 1H NMR spectrum, δ, ppm
(J, Hz): 4.07 (2H, s, CH2); 7.73 (2Н, d, J = 8.8, H Ar); 8.35
(2Н, d, J = 8.8, H Ar). The substance is not obtained in
analytically pure form.
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1
Supplementary information file containing IR, Н and
13С NMR, and mass spectra of compounds 1a–e, 3a–e, is
available from the journal website at http://
link.springer.com/journal/10593.
21. Ammar, Y. A.; El-Sharief, A. M. Sh.; Al-Sehemi, A. G.;
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This work was performed with financial support from
the Russian Foundation for Basic Research (grant 16-33-
00560 mol_a) and the Government of Russian Federation
(assignment No. 211, contract No. 02.A03.21.0006).
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