Reactions of 3-substituted 5-arylmethylene-1,3-thiazolidin-2,4-diones with azide and cyanide ions

Article abstract of DOI:10.1080/10426500601160967

3-substituted-5-arylmethylene-1,3-thiazolidine-2,4-diones 3a-e react- ed with sodium azide to afford pyrazolinone derivatives 8a-d as well as 5-(4-chlorophenylmethylene)-1,3-thiazolidine-2,4-dione 7a in the case of 3d and 5-(4-methoxyphenylmethylene-1,3-t

Full text of DOI:10.1080/10426500601160967

This article was downloaded by: [University of Bristol]
On: 26 January 2015, At: 11:50
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954
Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH,
UK
Phosphorus, Sulfur, and Silicon
and the Related Elements
Publication details, including instructions for
authors and subscription information:
http://www.tandfonline.com/loi/gpss20
Reactions of 3-substituted
5-Arylmethylene-1,3-
Thiazolidin-2,4-diones with
Azide and Cyanide Ions
Ahmed Said Ahmed Youssef a
a Chemistry Department , Ain Shams University ,
Abbassia, Cairo, Egypt
Published online: 29 Aug 2007.
To cite this article: Ahmed Said Ahmed Youssef (2007) Reactions of 3-substituted
5-Arylmethylene-1,3-Thiazolidin-2,4-diones with Azide and Cyanide Ions,
Phosphorus, Sulfur, and Silicon and the Related Elements, 182:6, 1335-1349, DOI:
10.1080/10426500601160967
To link to this article: http://dx.doi.org/10.1080/10426500601160967
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the
information (the “Content”) contained in the publications on our platform.
However, Taylor & Francis, our agents, and our licensors make no
representations or warranties whatsoever as to the accuracy, completeness,
or suitability for any purpose of the Content. Any opinions and views
expressed in this publication are the opinions and views of the authors, and
are not the views of or endorsed by Taylor & Francis. The accuracy of the
Content should not be relied upon and should be independently verified with
primary sources of information. Taylor and Francis shall not be liable for any
losses, actions, claims, proceedings, demands, costs, expenses, damages,
and other liabilities whatsoever or howsoever caused arising directly or

indirectly in connection with, in relation to or arising out of the use of the
Content.
This article may be used for research, teaching, and private study purposes.
Any substantial or systematic reproduction, redistribution, reselling, loan,
sub-licensing, systematic supply, or distribution in any form to anyone is
expressly forbidden. Terms & Conditions of access and use can be found at
http://www.tandfonline.com/page/terms-and-conditions

Phosphorus, Sulfur, and Silicon, 182:1335–1349, 2007
Copyright © Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426500601160967
Reactions of 3-substituted
5-Arylmethylene-1,3-Thiazolidin-2,4-diones
with Azide and Cyanide Ions
Ahmed Said Ahmed Youssef
Chemistry Department, Ain Shams University, Abbassia, Cairo, Egypt
3-substituted-5-arylmethylene-1,3-thiazolidine-2,4-diones 3a–e react- ed with
sodium azide to afford pyrazolinone derivatives 8a–d as well as 5-(4-
chlorophenylmethylene)-1,3-thiazolidine-2,4-dione 7a in the case of 3d and 5-(4-
methoxyphenylmethylene-1,3-thiazolidin-2,4-dione 7b as a sole product in the case
of 3e. Reactions of potassium cyanide with 3b–d gave butyronitrile derivative 9 as
well as 7a and a water soluble adduct that, upon treatment with chloroacetic acid,
yielded 10 in the case of 3c and 3d. Also, the treatment of 3e with potassium cyanide
afforded a mixture of 7b, but-3-enonitrile derivative 11 and 10. Structures of all
products were elucidated by microanalytical and spectral data.
Keywords 5-arylmethylene-1,3-thiazolidin-2,4-diones; 2-oxo-but-3-enonitrile; butyroni-
trile derivative; pyridazine derivatives; pyrazolinone derivatives
INTRODUCTION
It has been reported1−4 that 3-substituted-5-arylmethylene-1,3-
thiazolidin-2,4-diones react with hydrazines, morpholine, benzylamine,
and piperidine to afford pyrazolinones, thiolopropenamides, arylamino-
carboxamide, and N-phenylacrylamide derivatives, respectively. How-
ever, the 3-unsubstituted derivatives gave, upon treatment with hy-
drazine hydrate and piperidine, the corresponding triazinone3,5 and
acrylamide derivatives.6 The latent ability of this ring system to cleave
at 1,2- as well as 3,4- bonds encouraged us to synthesize some 3-
substituted 5-arylmethylene-1,3-thiazolidin-2,4-diones to investigate
the behavior of this ring toward azide and cyanide ions that had previ-
ous not be studied.
Received September 11, 2006; accepted November 18, 2006.
Address correspondence to Ahmed Said Ahmed Youssef, Chemistry Department, Fac-
ulty of Science, Ain Shams University, P.O. Box 11566, Abbassia, Cairo, Egypt. E-mail:
ahmedy84@hotmail.com
1335

1336
A. Said Ahmed Youssef
RESULTS AND DISCUSSION
The starting materials (3a,b) were synthesized by condensing 3-phenyl-
1,3-thiazolidin-2,4-dione (1b) with the appropriate aldehyde using
sodium acetate-acetic acid.6 However, (3c–e) were prepared following
the method of Lo et al.7 by treating the potassium salt of the respec-
tive N-unsubstituted analogues obtained from 1,3-thiazolidin-2,4-dione
1a and the appropriate aldehyde with allyl or isopropyl bromide in
dimethylformamide and were shown to be mixtures of the (E) and (Z)-
isomers,3 as represented in Scheme 1. In the present study, the (E,Z)-
mixtures were used without separation.
SCHEME 1
Unfortunately, attempts to prepare new 5-arylidene-1,3-thiazolidin-
2,4-diones through the condensation of (1a,b) with benzoin (4a), 4-
methoxybenzoin (4b), and benzoylacetone (4c) gave a poor yield of
adducts.
Thus reacting equimolar amounts of 1,3-thiazolidin-2,4-dione (1a)
with benzoin (4a), 4-methoxybenzoin (4b), or benzoylacetone (4c) in re-
fluxing toluene in the presence of ammonium acetate as a base afforded
a mixture of 5a (major), and 6a (minor), 5b, or 6b, respectively. Simi-
lar treatment of 3-phenyl-1,3-thiazolidin-2,4-dione (1b) with 4a gave a
mixture of 5a (major) and 6c (minor).
The structures of compounds 5 and 6 were elucidated from their
analytical and spectral data. The infrared spectra of 5 showed absorp-
tion bands corresponding to C N and/or C C. However, those of com-
pounds 6 exhibited stretching absorptions assignable to NH and/or OH
as well as two strong absorptions, which were characteristic of C O

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1337
SCHEME 2
1
in the respective systems. The H NMR spectra of compounds 5 and
6a,c were in accord with the proposed structures. Compound 5b ex-
hibited a singlet signal for methoxy protons. However, compounds 6a,c
revealed exchangeable singlets for OH and/or NH protons as well as
singlet signals for methine protons. The downfield value for the OH
proton signal of compounds 6a,c suggested the existence of chelation
with the 4-oxo group of the heteroring. Further elucidation was gained
from EI-MS spectra that showed peaks for compounds 5. However,
the EI-MS spectra of compounds 6a,b did not show the molecular ion
peaks; instead they showed (M+.–
) peak for compound 6a and (M+.
HNCO CH C(OH)CH3) peak in the case of 6b, beside some of abun-
dant peaks.
SCHEME 3
The formation of compounds 5 is shown in Scheme 3.
The treatment of (E,Z)-3-substituted-5-arylmethylene-1,3-thiazoli-
din-2,4-diones 3a–d with sodium azide (3 equiv.) in refluxing dimethyl-

1338
A. Said Ahmed Youssef
SCHEME 4
formamide afforded the pyrazolinone derivatives 8a–d (major) as well
as 5-(4-chlorophenylmethylene)-1,3-thiazolidin-2,4-dione (7a) in a mi-
nor amount in the case of 3d. Similar treatment of 3e with sodium
azide yielded 5-(4-methoxyphenylmethylene)-1,3-thiazolidin-2,4-dione
as sole products.
The structure of compounds 8a–d was substantiated from their ana-
lytical and spectral data. Their infrared spectra showed stretching ab-
sorptions assignable to OH, C O, and C C groups of pyrazolinones.8
1
The HNMR spectra of 8 were in good agreement with the suggested
structure. Further elucidation was gained from their EI-MS where they
did not show the molecular ion peak; instead a peak corresponding
to M+. −16. The fragmentation pathway of compounds 8 is shown in
Scheme 5.
The structure of compounds 7a and 7b was rigidly confirmed by mix-
ture m.p. with authentic samples.7
The formation of compounds 7 and 8 (cf. Scheme 6) could be rational-
ized on the basis of an attack of the azide ion at the allyl or isopropyl
group to afford the anion A. Protonation of this anion yielded adducts 7a
and 7b (route a). The thiazolidine ring opening through an attack of the
azide ion at the 2-oxo- group followed by Curtius rearrangement gave
the isocyanate intermediate (B). Successive hydrolysis, intramolecular
cyclization followed by elimination of hydrogen sulfide, afforded the
pyrazolinone salt C. Acidification of (C) gave compounds 8 (route b).
However, treating (E,Z)-3-phenyl-5-(4-chlorophenylmethylene)-
(3b)-, (E,Z)-3-allyl-5-(4-chlorophenylmethylene)-(3c)-, and (E,Z)-3-
isopropyl-5-(4-chlorophenylmethylene)-(3d)-1,3-thiazolidin-2,4-diones
with potassium cyanide in a boiling mixture of methanol and diox-
ane afforded 4-cyano-4-(4-chlorophenyl)-2-oxobutyronitrile (9) as
well as (E,Z)-5-(4-chlorophenylmethylene)-1,3-thiazolidin-2,4-dione
(7a) and a water soluble adduct that, upon treating its methanolic

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1339
SCHEME 5
solution with chloroacetic acid, gave ammonium chloroacetate (10)
in the case of 3c and 3d. Similar treatment of (E,Z)-3-allyl-5-(4-
methoxyphenylmethylene)-1,3-thiazolidin-2,4-dione (3e) with potas-
sium cyanide gave a mixture of (E,Z)-5-(4-methoxyphenylmethylene)-
1,3-thiazolidin-2,4-dione (7b), but-3-enonitrile derivative 11 and a
water soluble adduct that yielded compound 10 upon treating its
methanolic solution with chloroacetic acid.

1340
A. Said Ahmed Youssef
FIGURE 6

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1341
FIGURE 7
The structures of compounds 9 and 11 were substantiated from their
analytical and spectral data. Their IR spectra exhibited stretching ab-
sorptions for CN and CO groups beside an additional absorption for the
SH group in the case of compound 11.
The 1H NMR spectrum of compound 9 was consistent with the sug-
gested structure as it showed from low to high field the signals of aro-
matic, methine, and methylene protons. Its EI-MS spectrum did not
show the molecular ion peak, but it showed a peak at m/e 190 that cor-
responds to (M+. – CO). The fragmentation pathway is represented in
Scheme 7.
1
The HNMR spectrum of 11 revealed the existence of two closely
spaced singlets for protons of two methoxy groups, an exchangeable
singlet for the SH proton, as well as two doublet signals for aromatic
protons. Moreover, the structure of 11 got further support from its EI-
MS as it showed the molecular ion peak beside some abundant peaks.
The fragmentation pattern is shown in Scheme 8.
The structures of compounds 7a and 7b were rigidly confirmed by
m.p. comparison with those reported.7 However, the structure of 10 was
confirmed by mixture m.p. with authentic speciment.
The overall picture for the mode of action of the cyanide ion
on 3-aryl and 3-alkyl substituted-5-arylmethylene-1,3-thiazolidin-2,4-
diones 3b–e is easily visualized as represented by type (A) and type
(B) (cf. Scheme 9). Type (A) involves an initial attack by the cyanide
ion at the allyl or isopropyl group to afford the anion (A). Protonation
of this anion yielded the adducts 7a and 7b. Thiazolidine ring opening
of this anion at the 1,2-bond gave the thiolate anion (B), which un-
derwent 3,4-bond cleavage to give isocyanate (C) and thirane (D). The

1342
A. Said Ahmed Youssef
FIGURE 8
addition of water to (C) gave the carbamate (E), which, on treatment
of its methanolic solution with chloroacetic acid, afforded 10. A thirane
ring opening through attack by the CN− ion at the 2-oxo group followed
by the addition of the solvent molecule (MeOH)9 at the β-carbon of the
exocyclic double bond gave the methoxy adduct (F). Oxidation of the
methoxy adduct (F) afforded (G), which, upon protonation, yielded 11.
Type (B) involves the thiazolidine ring opening through successive
cleavage at the 1,2- as well as the 3,4-bonds to give the isocyanate
(H) and the thirane (D). The thirane ring opening through attack by

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1343
FIGURE 9

1344
A. Said Ahmed Youssef
the cyanide ion at the 2-oxo group followed by reaction of the formed
thiolate ion with the isocyanate (H) gave (I). Cleavage of (I) yielded
the thiocarbamate (J) and the acetylenic ketone (K). Attack by an-
other cyanide ion at the β-acetylenic carbon of (K) followed by reduction
afforded 9.
CONCLUSION
It is inferred that reactions of 3-substituted-5-arylmethylene-1,3-
thiazolidine-2,4-diones with azide and cyanide iones proceed through
1,2- as well as 3,4- bond cleavage, as reported1−4 before with hydrazines,
morpholine, benzyl amine, and piperidine, and not through an attack at
the β-carbon of the exocyclic double bond as reported10 in the reaction
of 4-methoxyphenylazide with 3-substituted-5-arylmethylene-4-oxo-2-
thioxo-1,3-thiazolidine.
EXPERIMENTAL
All melting points are uncorrected. IR spectra were measured on a Uni-
cam SP1200 spectrometer as KBr discs. Unless otherwise stated, the
1HNMR spectra were measured in CDCl3 solution on Varian Gemini
200 MHz or Brucker ES 200 MHz instruments with chemical shift (δ)
expressed in ppm downfield from Me4Si. Mass spectra were recorded on
Shimadzu GC-MS-QP 1000 Ex or Finnigan GCQ instruments operating
at 70 eV. Column chromatography and TLC10,11 were run using Silica
Gel Voein, activity III/30 mm according to Brockmann and Schodder
and TLC aluminium sheets Silica Gel 60 F254 (Merck).
Reactions of (1a,b) with (4a–c)
A solution of (1a) or (1b) (10 mmoles) and (4a–c) (10 mmoles) in 25 mL
toluene in the presence of ammonium acetate (2.31 g, 30 mmoles) was
refluxed for 15 h. The reaction mixture was cooled and then poured into
cold water. The toluene layer was dried over anhydrous calcium chlo-
ride, concentrated, and left to stand over night at room temperature.
The precipitated solid was recrystallized from a proper solvent to give
the adducts 5b and 6b in the case of reactions of 1a with 4b and 4c. The
adduct 5a was isolated from the reaction of 1a with 4a, and the residual
oil was chromatographed over silica gel. Elution with petroleum ether
(b.p. 40–60)/ ether (4 : 1 V / V) gave 6a. The precipitated solid in the case
of the reaction of 1b with 4a was fractionally crystallized to give first
6c as yellow crystals (ethanol). The insoluble part in boiling ethanol
was recrystallized from benzene to give 5a as white crystals.

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1345
2,3,5,6-Tetraphenyl-1,4-diazine (5a)
1.5 g (30%) white crystals (benzene), m.p. 241–243 ◦C; IR: νmax = 3080
(aryl-H), 1615 (C C and/or C N), 760, 690 cm−1. 1HNMR: δ 7.31–7.68
(m, 20, ArH). EI-MS m/z (%) 384 (M+., 77), 383 (68), 179 (14), 178 (base),
177 (20), 176 (35), 152 (20), 151 (14), 103 (13), 77 (10), 76 (13), 51 (11).
Anal. calcd. for C28H20N2: C, 87.47; H, 5.24; N, 7.29. Found : C, 87.21;
H, 5.49; N, 7.10%.
2,6-Diphenyl-3,5-di-(4-methoxyphenyl)-1,4-diazine (5b)
1.1 g (25%), white crystals (methanol-benzene), m.p. 190–192◦C; IR:
νmax = 3020 (aryl-H), 2920, 2830 (alkyl-H), 1610 (C C and/or C N),
1
835, 760, 700 cm−1. HNMR: δ 3.83 (s, 6, 2OCH3), 6.83–7.69 (m, 18,
ArH). EI-MS m/z (%) 444 (M+., base), 443 (53), 208 (31), 193 (54), 165
(50), 164 (17), 163 (11), 139 (11), 104 (25). Anal. calcd. for C30H24N2O2:
C, 81.06; H, 5.44; N, 6.30. Found: C, 81.22; H, 5.11; N, 6.45%.
5-(1,2-Diphenyl-2-hydroxy)ethylene-1,3-thiazolidin-2,4-dione
(6a)
0.37 g (12%), yellow crystals (ethanol), m.p. 314-316 ◦C; IR: νmax = 3340,
3130 (OH and/or NH), 3055 (aryl-H), 2930, 2860 (alkyl-H), 1740, 1690
(C O), 765, 690 cm−1. 1HNMR: δ 4.02 (s, 1, CH), 7.24-7.42 (m, 10, ArH),
10.01 (br.s, 1, OH exchangeable), 10.15 (br.s, 1, NH exchangeable). EI-
MS m/z (%) 311 (M+., missed), 236 (M+.
–
, 88), 165 (16), 105 (63), 104
(base), 103 (16), 77 (51), 76 (12), 51 (35). Anal. calcd. for C17H13NO3S:
C, 65.58; H, 4.21; N, 4.49. Found: C, 65.41; H, 4.46; N, 4.19%.
5-(1-Phenyl-3-hydroxy)-but-2-en-1-ylene-1,3-thiazolidin-2,4-
dione (6b)
0.39 g (15%), pale yellow crystals (ethanol), m.p. 140-142 ◦C; IR: νmax
=
3314, 3160 (OH and/or NH), 3060 (aryl–H), 2983, 2875 (alkyl-H), 1743,
1635 (C O), 1595 (C C), 641, 754 cm−1. EI-MS m/z (%) 261 (M+.,
missed), 161 (M+. – HNCO CH C(OH)CH3, 38), 160 (88), 84 (base),
77 (33), 51 (29). Anal. calcd. for C13H11NO3S : C, 59.76; H, 4.24; N, 5.36.
Found: C, 59.42; H, 4.39; N, 5.29%.

1346
A. Said Ahmed Youssef
3-Phenyl-5-(1,2-diphenyl-2-hydroxy)ethylene-1,3-thiazolidin-
2,4-dione (6c)
0.77 g (20%), yellow crystals (ethanol), m.p. 138–140◦C, IR: νmax = 3380,
3210 (OH and/or NH), 3070 (aryl–H), 2985, 2874 (alkyl-H), 1728, 1676
(C O), 752, 692 cm−1. 1HNMR: δ 4.1 (s, 1, CH) 7.18–7.51 (m, 15, ArH),
10.12 (br.s, 1, OH exchangeable) Anal. calcd. for C23H17NO3S: C, 71.29;
H, 4.42; N, 3.62. Found: C, 71.48; H, 4.23; N, 3.79%.
Reactions of 3-Substituted-5-arylmethylene-1,3-thiazolidin-
2,4-diones (3a–e) with Sodium Azide
A mixture of (3a–e) (10 mmoles) and sodium azide (1.95 g, 30 mmoles)
was refluxed in dimethylformamide (20 mL) for 20 h. The color of the
reaction mixture changed from yellow to brown to orange, and then to
yellow again. The precipitated solid during the reaction was filtered off;
part of it was dissolved in water and then acidified with ice cold HCl,
where no precipitate was obtained. This solid was not identified due to
its very poor yield and the difficulty of doing detailed characterization
as it is insoluble in all organic solvents and its m.p. is >300◦C . The re-
action mixture was cooled, concentrated, and then poured into ice cold
water. The precipitated solid was recrystallized from a proper solvent
to give (10–15%) of unreacted starting materials 3a–e. The filtrate was
acidified with ice cold HCl. The solid obtained was fractionally crystal-
lized to afford 7a and 7b in the case of 3d and 3e (identical m.p. with
the reported7), and 8a–d, respectively.
E,Z-5-(4-Chlorophenylmethylene)-1,3-thiazolidin-2,4-dione
(E,Z-7a)
0.6 g (10%); yellow crystals (ethanol-benzene), m.p. 224–226◦C, Lit.7,
m.p. 223–225◦C.
E,Z-5-(4-Methoxyphenylmethylene)-1,3-thiazolidin-2,4-dione
(E,Z-7b)
0.7 g (12%), yellow crystals (ethanol), m.p. 208–210◦C, Lit.,7 m.p. 212–
214◦C.
1-Carboxy-2-phenyl-3-oxo-5-(4-methoxyphenyl)-2,3-
dihydropyrazole (8a)
1.55 g (50%), colorless crystals (ethanol-benzene), m.p. 152–154◦C; IR:
νmax = 3400, 3150 (br.) (OH), 1665 (C O), 1600 (C C), 1550 (pyrazole

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1347
ring), 830, 690 cm−1. 1HNMR : δ 3.77 (s, OMe), 6.89–7.97 (m, 10, ArH +
CH=), 9.1 (br.s, 1, OH exchangeable). EI-MS m/z (%) 310 (M+., missed),
294 (M+. – 16, 23), 202 (26), 146 (15), 135 (24), 134 (19), 119 (25), 93
(base), 77 (20), 76 (15), 65 (16), 51 (17). Anal. calcd. for C17H14N2O4: C,
65.80; H, 4.55; N, 9.03. Found: C, 65.97; H, 4.35; N, 8.89%.
1-Carboxy-2-phenyl-3-oxo-5-(4-chlorophenyl)-
2,3-dihydropyrazole (8b)
1.73 g (55%), colorless crystals (xylene), m.p. 208–210◦C; IR: νmax
=
3389, 3196 (br.) (OH), 1671 (C O), 1601 (C C), 1548 (pyrazole ring),
829, 747, 684 cm−1. 1HNMR : δ 7.37–7.98 (m, 10, ArH + CH ), 8.92 (br.s,
1, OH exchangeable). EI-MS m/z (%) 314 (M+., missed), 300 (M+.+ 2 −
16, 5), 298 (M+. − 16, 15), 206 (19), 139 (12), 123 (15), 93 (base) 77 (12),
65 (12), 51 (10). Anal. calcd. for C16H11ClN2O3: C, 61.06; H, 3.52; N,
8.90. Found: C, 61.20; H, 3.39; N, 8.74%.
1-Carboxy-2-allyl-3-oxo-5-(4-chlorophenyl)-2,3-
dihydropyrazole (8c)
1.33 g (48%), metallic needles (ethanol), m.p. 130–132◦C; IR: νmax
=
3400, 3118 (br.) (OH), 2980, 2906 (alkyl-H), 1668 (C O), 1637, 1612
(C C), 1559 (pyrazole ring), 824 cm−1. 1HNMR: δ 4.08 (m, 2, N CH2),
5.22 (m, 2, CH2 CH ), 5.91 (m, 1, CH2 CH ), 7.28–7.87 (m, 5, ArH
+ CH ), 13.05 (br.s, 1, OH exchangeable). EI-MS m/z (%) 278 (M+.,
missed), 264 (M+.+ 2 − 16, 13), 262 (M+. − 16, 37), 247 (14), 208 (16),
206 (46), 138 (14), 123 (19), 114 (10), 57 (81), 56 (base). Anal. calcd. for
C13H11ClN2O3: C, 56.03; H, 3.98; N, 10.05. Found: C, 55.84; H, 4.12; N,
10.21%.
1-Carboxy-2-isopropyl-3-oxo-5-(4-chlorophenyl)-2,3-
dihydropyrazole (8d)
1.49 g (53%), colorless crystals (benzene-ethanol), m.p. 145–147◦C; IR:
νmax = 3406, 3104 (br.) (OH), 3050 (aryl-H), 2948, 2899 (alkyl-H), 1669
(C O), 1550 (pyrazole ring), 820 cm−1. 1HNMR: δ 1.26 (d, 2CH3, J = 6.5
Hz), 4.26 (m, 1, CH(CH3)2, J = 6.6 Hz), 7.25–7.79 (m, 5, ArH + CH ),
12.41 (br.s, 1, OH exchangeable). EI-MS m/z (%) 280 (M+., missed), 266
(M+.+ 2 − 16, 5) 264 (M+. − 16, 16), 249 (16), 208 (14), 206 (43), 138
(13), 123 (19), 58 (base). Anal. calcd. for C13H13ClN2O3: C, 55.62; H,
4.67; N, 9.98. Found: C, 55.41; H, 4.81; N, 9.66%.

1348
A. Said Ahmed Youssef
Reactions of (3b–e) with Potassium Cyanide
A solution of (25 mL) dioxane containing 3a–e (10 mmoles) and potas-
sium cyanide (1.95 g, 30 mmoles) was heated to 90◦C for 25 min. During
the reflux, 30 mL of methanol was added in five equal portions. The
mixture was refluxed for 4 h. The precipitated solid during heating was
filtered off and dissolved in water. Acidification with ice cold HCl was ac-
companied by effervescence without precipitation of a solid. Treatment
of a methanolic solution of this solid with chloroacetic acid afforded
10. The reaction mixture was concentrated and left to stand at room
temperature for 2 h. The precipitated solid was filtered off, dissolved
in water, and acidified with ice cold HCl to give a solid. Crystallization
from ethanol–benzene afforded 7a in the case of 3c and 3d, in a yield
of 8%, m.p. 225–227◦C (identical with the reported7), and 7b as an E/Z
mixture in a ratio of 35:65 in the case of 3e, with a yield of 10%, m.p.
208–210◦C (identical with the reported7). On leaving the mother liquor
over night at room temperature, afforded compound 9 in the case of 3b,
3c, & 3d, while 11 was obtained in the case of 3e.
Ammonium Chloroacetate (10)
0.12 g (11%), white crystals (methanol), m.p. 137–139◦C (undepressed
on an admixture with an authentic sample prepared by passing ammo-
nia gas over a methanolic solution of chloroacetic acid); IR: νmax = 3401
1
(NH), 2962, 2942, 2855 (alkyl-H), 1648 cm−1 (C O). HNMR (DMSO-
d6): δ 4.04 (s, 2, CH2) , 4.83 (br.s, 4, NH4 exchangeable). EI-MS m/z
(%) 111 (M+., missed), 96 (M+.+ 2 NH3, 1.4), 94 (M+. NH3, 4.2), 79
(ClCH2 C≡O+, 1.3), 78 (ClCH C O, 0.5), 77 (ClCH2C≡O+, 4.3), 76
(ClCH C O, 1), 58 (M+. NH3 HCl, 1), 50 (M+. NH3 CO2, base).
4-Cyano-4-(4-chlorophenyl)-2-oxobutyronitrile (9)
0.87–1.31 g (40–60%), creamy crystals (ethanol), m.p. 87–89◦C; IR:
νmax = 3050 (aryl-H), 2973, 2945 (alkyl-H), 2247 (CN), 1657 (C O), 825
cm−1. 1HNMR: δ 2.97 (m, 2, CH2, J = 6.4 Hz), 4.15 (t, 1, CH, J = 6.8 Hz),
ꢀ
ꢀ
7.37 (d, 2, Ha, Ha , Jo = 6.8 Hz), 7.46 (d, 2, Hb, Hb , Jo = 6.8 Hz). EI-MS
m/z (%) 218 (M+., missed), 192 (M+.+ 2 CO, 7), 190 (M+. CO, 19),
152 (M+.+ 2 CH2COCN, 36), 150 (M+. CH2COCN, base), 115 (11),
88 (11), 75 (22), 74 (14), 63 (20), 62 (13), 61 (11), 51 (21), 50 (34). Anal.
calcd. for C11H7ClN2O: C, 60.43; H, 3.23; N, 12.81. Found: C, 60.25; H,
3.31; N, 12.56%.

3-Substituted 5-Arylmethylene-1,3-Thiazolidin-2,4-Diones
1349
3-Mercapto-4-methoxy-4-(4-methoxyphenyl)-2-oxo-but-
3-enonitrile (11)
1.2 g (48%), pale brown crystals (ethanol), m.p. 279–281◦C; IR: νmax
=
3001 (aryl-H), 2929, 2840 (alkyl-H), 2423 (SH), 2056 (CN), 1673 (C O),
1
1607 (C C), 817 cm−1. HNMR (DMSO-d6): δ 3.76, 3.77 (two singlets,
ꢀ
2OCH3), 2.49 (br.s, 1, SH exchangeable), 7.01 (d, 2, Ha, Ha , Jo = 8.8
+.
ꢀ
Hz), 7.47 (d, 2, Hb, Hb , Jo = 8.6 Hz). EI-MS m/z (%) 251 (M + 2, 6),
249 (M+., 68), 237 (2), 235 (30), 216 (17), 191 (13), 174 (18), 173 (26),
165 (11), 164 (base), 163 (49), 149 (69), 148 (18), 145 (25), 121 (22), 120
(22), 119 (12), 94 (12), 89 (14), 82 (10), 77 (25), 69 (13), 63 (14), 62 (13),
51 (17), 50 (11). Anal. calcd. for C12H11NO3S: C, 57.82; H, 4.45; N, 5.62.
Found: C, 57.52; H, 4.62; N, 5.74%.
REFERENCES
[1] M. T. Omar, M. M. Habashy, A. M. Youssef, and F. A. Sherif, J. Prakt. Chemie., 331,
393 (1989).
[2] M. T. Omar and F. A. Sherif, Synthesis, 9, 742 (1981).
[3] A. R. A. Raouf, M. T. Omar, and M. M. El-Attal, Acta. Chimica. Sci. (Hung.), 87, 187
(1975).
[4] A. R. A. Raouf, M. T. Omar, and M. M. El-Attal, Acta. Chimica. Sci. (Hung.), 83, 367
(1975).
[5] M.T. Omar, M. M. Habashy, and A. El-Khamry, Aust. J. Chem., 33, 619 (1980).
[6] E. Campaigne and R. E. Cline, J. Org. Chem., 21, 32 (1956).
[7] C. P. Lo, E. Y. Shorpshire, and W. J. Croxall, J. Am. Chem. Soc., 75, 4845 (1953).
[8] J. Elguero, C. Marzin, A. R. Katritzky, and P. Linda, The Tautomerism of Heterocycles
(Academic Press, New York, 1976).
[9] D. Papa, E. Schwenk, F. Villiani, and E. Klingsberg, J. Am. Chem. Soc., 70, 3555
(1948).
[10] M. T. Omar, A. S. A. Youssef, and K. A. Kandeel, Phosphorus, Sulfur and Silicon,
162, 25 (2000).
[11] K. A. Kandeel and A. S. A. Youssef, Molecules, 6, 510 (2001).