One-pot synthesis of some nitrogen and sulfur heterocycles using thiosemicarbazide under microwave irradiation in a solventless system

Article abstract of DOI:10.1080/104265090968992

A thiazolon, triazines, and triazinones were synthesized under microwave irradiation in a, solventless system in a very short time and in excellent yields. Copyright Taylor & Francis LLC.

Full text of DOI:10.1080/104265090968992

This article was downloaded by: [University of Arizona]
On: 15 August 2013, At: 02:43
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
One-Pot Synthesis of
Some Nitrogen and Sulfur
Heterocycles Using
Thiosemicarbazide Under
Microwave Irradiation in a
Solventless System
a
a
Majid M. Heravi , Navabeh Nami , Hossien A.
a
a
Oskooie & Rahim Hekmatshoar
a
Department of Chemistry, School of Sciences,
Azzahra University, Vanak, Tehran, Iran
Published online: 01 Feb 2007.
To cite this article: Majid M. Heravi , Navabeh Nami , Hossien A. Oskooie & Rahim
Hekmatshoar (2006) One-Pot Synthesis of Some Nitrogen and Sulfur Heterocycles
Using Thiosemicarbazide Under Microwave Irradiation in a Solventless System,
Phosphorus, Sulfur, and Silicon and the Related Elements, 181:1, 87-91, DOI:
10.1080/104265090968992
To link to this article: http://dx.doi.org/10.1080/104265090968992
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, 181:87–91, 2006
Copyright © Taylor & Francis LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/104265090968992
One-Pot Synthesis of Some Nitrogen and Sulfur
Heterocycles Using Thiosemicarbazide Under Microwave
Irradiation in a Solventless System
Majid M. Heravi
Navabeh Nami
Hossien A. Oskooie
Rahim Hekmatshoar
Department of Chemistry, School of Sciences, Azzahra University,
Vanak, Tehran, Iran
A thiazolon, triazines, and triazinones were synthesized under microwave irradia-
tion in a solventless system in a very short time and in excellent yields.
Keywords α-chloroacetic acid; benzil; diethyl acetylendicarboxylate; diketone; dimethyl
acetylendicarboxylate; thiosemicarbazide; triazine
1
,2,4-triazines, 1,2,4-triazinones, and thiazolones are an important
class of heterocyclic compounds with a particularly wide range of
biological properties. There has been considerable attention in the cre-
1
ation and development of evergreen and solventless methods in organic
2
3
methodology, dictated by stringent environmental protection laws.
Organic solvents are not only expensive, but are often flammable, toxic,
and environmentally hazardous.
Microwave irradiation in organic synthesis is a useful technique
4
−7
today.
Dry media using microwave thermolysis have attracted much
attention because it omits the use of hazardous and relatively ex-
pensive organic solvents, and the reaction can be conducted in open
8
vessels.
Solvent-free organic reactions or dry-media techniques under mi-
crowave irradiation are one of the main topics of research in our
9
laboratory. We have reported recently the synthesis of heterocyclic
1
0
systems under microwave irradiation in a solventless system. In view
of the current trust on solventless systems, there is merit in developing
Received December 14, 2004; in final form January 6, 2005.
Address correspondence to Majid M. Heravi, Azzahra University, Department of
Chemistry, School of Sciences, Vanak, Tehran, Iran. E-mail: mmheravi@azzarha.ac.ir
87

8
8
M. M. Heravi et al.
a truly solvent-free condition for the synthesis of heterocyclic systems.
Herein we wish to report our results for the synthesis of some useful ba-
sic heterocyclic systems, which are interesting from the biological point
of view as well as for the use as precursors for the synthesis of fused
bicyclic heterocycles.
1
,2,4-triazines (1a–c) were prepared from the condensation of
thiosemicarbazide with diketons (RCOCOR, R H, Ph, CH3) under mi-
crowave irradiation in a solventless system (Scheme 1). These compo-
1
1
unds have been synthesized under conventional heating in solvents.
Reaction of thiosemicarbazide with Dimethyl Acetylendicarboxy-
late (DMAD) and Diethyl Acetylendicarboxylate (DEAD) in either
hot methanol or in a solventless system under microwave irradia-
tion gave 3-mercapto-6-(methoxycarbonylmethylen) 1,2,4-triazine-5(4)-
one(2a) and 3-mercapto-6-(ethoxycarbonylmethylen)1,2,4-triazine-5(4)
-
one(2b), respectively.
-hydrazinothiazolon-5-one (3) was prepared from the condensation
2
reaction of thiosemicarbazide with chloroacetic acid under microwave
irradiation in a solventless system. This reaction needs a long reaction
1
2
time and a solvent under conventional heating.
SCHEME 1

One-Pot Synthesis
89
In conclusion, these procedures for the synthesis of the previously
mentioned heterocycles have some advantages over the existing meth-
ods and will make a useful and important addition to the present
methods. The main advantages of these new methods are a mild re-
action condition, reduced reaction times, high yields, and a minimum
requirement for expensive and hazardous solvents.
EXPERIMENTAL
The melting points were obtained on Electrotermal IA 9100 Digital
Melting Point apparatus. The IR spectra were recorded on a 4300
1
Shimadzu spectrometer. HNMR spectra were recorded on a 300 MHZ
spectrometer using TMS as internal standard. The microwave oven
used was an LG MOD MC-838 WR.
General Procedure
Two reactants were mixed in a beaker thoroughly using a spatula. The
beaker was placed in a microwave oven for the specified time. The
progress of the reaction was indicated by TLC using n-hexan:ethyl
acetate (1:3). The crude product was crystallized from an appropri-
ate solvent. The selected physical and spectroscopic data are given
below.
Selected Data for 3-Mercapto-1,2,4-triazine 1a
m.p. > 300 C, yellow brownish powder from EtOH (Lit.11 decom. 310 C),
◦
◦
−
1
Yield 93%. Irradiation time: 7 min (900 W). IR (KBr) (νmax, cm ):
3
1
161(NH str), 3010 CH str), 1606(C C), 1519(C C), 1470, 1308, 1274,
088, 1053, 915, 836, 717, 669, 623.
Selected Data for 5,6-Diphenyl-3-mercapto-1,2,4-triazine 1b
◦
11
◦
m.p. = 224 C, yellow orange powder from AcOH, (Lit. 225–822 C),
−
1
Yield 90%, Irradiation time: 6 min (900W). IR (KBr) (νmax, cm
)
3
121(NH str), 3050 ( CH str), 1559(C C), 1535(C C), 1444, 1367,
1
1333, 1179, 1053, 1026, 766, 695. HNMR: δ (d6-DMSO), 7.55(m, 10H,
Ph), 7.70(br, 1H, NH).
Selected Data for 5, 6-Dimethyl-3-mercapto-1,2,4-triazine 1c
◦
11
◦
−
m.p. 233 C, yellow brownish powder from AcOH, (Lit. 233–723 C),
1
Yield 89%, Irradiation time: 7 min (900 W). IR (KBr) (νmax cm ):
125(NH str), 2864(RH, str), 1533(C C), 1446, 1366, 1329, 1223, 1181,
3

9
0
M. M. Heravi et al.
+
1
040, 1024, 879, 761, 695. MS, m/z; M , 141(100), 113(12), 91(65), 72(7),
54(46).
3
-Mercapto-6-(methoxycarbonylmethylene)1,2,4-
triazin-5(4)-One 2a
Method a
◦
m.p. = 168 C, yellow powder from MeOH, Yield 85%, Irradiation
−1
time: 9 min (720 W). IR (KBr) (νmax, cm ): 3339(NH str), 3316(NH str),
3
266(NH str), 3060( CH), 1740(CO ster), 1688(CO amid), 1608(C C),
441, 1398, 1338, 1212, 1137, 1011, 905, 815, 756, 712, 651, 606.
1
1
HNMR: δ (d6-DMSO), 10.10(br, 1H, NH amid), 8.82(br, 1H, NH), 6.74(s,
+
1H, CH), 3.73(s, 3H, OMe). MS, m/z; M , 201(100), 174(74), 142(41),
117(30), 85(52), 69(7), 57(26).
Method b
An equimolar mixture of thiosemicarbazide (1 mmol) and DMAD
1 mmol) was refluxed in MeOH (10 mL) for 20 min. After cooling, the
(
precipitated solid was filtered and dried to afford 2a (80%).
3
-Mercapto-6-(ethoxycarbonylmethylen) 1,2,4-
triazin-5(4)-One 2b
Method a
◦
m.p. = 135 C, yellow microneedles from EtOH, Yield 89%, Irradia-
−
1
tion time: 9 min (720 W). IR (KBr) (νmax, cm ): 3339(NH str), 3282(NH
str), 3241(NH str), 3032( CH), 2981(RH, str), 1740(CO ster), 1684(CO
amid), 1630(C C str), 1608(C C str), 1409, 1373, 1202, 955, 903, 858.
1
HNMR: δ (d6-DMSO), 10.08(br, 1H, NH amid), 8.51(br, 1H, NH), 6.53(s,
1H, CH), 4.51(q, J = 7, 2H, CH2), 1.45(t, J = 7, 3H, CH3).
Method b
An equimolar mixture of thiosemicarbazide (1 mmol) and DEAD
1 mmol) was refluxed in EtOH (10 mL) for 30 min. After cooling, the
(
precipitated solid was filtered and dried to afford 2b (76%).
Selected Data for 2-Hydrazinothiazol-5-One 3
◦
12
◦
m.p. = 230 C decom, brown powder from EtOH, (Lit. 230 C), Yield
−
1
8
9%, Irradiation time: 7 min (900 W). IR (KBr) (νmax, cm ) 3324(NH
str), 3196(NH2 str), 2989(HC H), 1721(CO str), 1613(C N str), 1388,
326, 1224, 891, 722, 697.
1
Caution
Although we did not have any accident using a microwave oven, an
efficient hood is highly recommended.

One-Pot Synthesis
91
REFERENCES
[
1] (a) I. Alexeeva, L. Pachikovskava, A. Shalamay, L. Nosach, V. Zhovnovataya, O.
Povnitsa, and N. Dyachenko, Acta Biochemical Polonica, 47, 95 (2000); (b) H. K.
Shukla, R. R. Astik, and K. A. Thaker, J. Ind. Chem. Soc., 58, 1192 (1981); (c) K. J.
Mehta and A. R. Parikh, Ind. J. Chem., 16B, 836 (1978).
[
[
[
[
2] K. Tanaka and F. Toda, Chem. Rev., 100, 1025 (2000).
3] C. B. Khour, C. B. Darth, A. Lalnger, and M. E. Daves, J. Catal., 149, 195 (1994).
4] S. Caddick, Tetrahedron, 30, 10403 (1995).
5] G. Bram, A. Loupy, M. Majdoub, E. Gutierrez, and E. R. Hitzky, Tetrahedron, 45,
5167 (1990).
[
[
6] R. Latouche, F. Texier-Boullet, and J. Hamelin, J. Tetrahedron Lett., 32, 1179 (1991).
7] I. Almena, E. Diez-Barra, A. de La Hoz, J. Ruiz, A. Sanchez-Migallon, and J. Elguero,
J. Heterocycl Chem., 35, 1263 (1998).
[
8] R. S. Varma and D. Komar, Tetrahedron Lett., 40, 7665 (1999).
[
9] (a) M. M. Heravi, D. Ajami, M. M. Mojtahedi, and M. Gghassemzadeh, Tetrahedron
Lett., 40, 766 (1999); (b) M. M. Heravi, D. Ajami, and M. Ghassemzadeh, Synthe-
sis, 393 (1999); (c) M. M. Heravi, D. Ajami, K. Aghapoor, and M. Ghassemzadeh,
Chem. Commun., 833 (1999); (d) M. M. Heravi, D. Ajami, and M. Gassemzadeh,
Synth Commun., 29, 1013 (1999); (e) M. M. Heravi, D. Ajami, M. Tajbakhsh, and M.
Ghassemzadeh, Monatsh. Chem., 131, 1109 (2000); (f) M. Tajbakhsh, M. M. Heravi,
A. Hosseini, and A. Shahrezaie, Phosphorus, Sulfur, and Silicon, 178, 773 (2003).
[
10] (a) M. M. Heravi, Gh. Rajabzadeh, M. Rahimizadel, M. Bakavoli, and M.
Gassemzadeh, Synth. Commun., 31, 2231 (2001); (b) A. Shokrawi, H. Sharghi, H.
Valizadeh, and M. M. Heravi, Phosphorus, Sulfur, and Silicon, 177, 2555 (2002);
(
c) A. Shokravi, M. M. Heravi, and H. Valizadeh, Phophorus, Sulfur, and Silicon,
178, 143 (2003); (d) K. Aghapour, M. M. Heravi, and M. A. Noushabadi, Indian,
J. Chem., 84 37B, (1998); (e) M. M. Heravi, M. A. Noushabadi, and K. Aghapour,
Phosphorus, Sulfur, and Silicon, 164, 95 (2000); (f) M. M. Heravi, K. Aghapour, and
M. A. Noushabadi, Monatsh, 120, 112 (1997).
[
11] (a) S. A. Marly, Soci e´ t e´ belge de l’azote et des produits chimiques belg, 503, 980 (1951);
(
b) J. Klosa. Arch. Pharm., 288, 465 (1955).
[
12] P. Chabrier and L. Palla, Compt. Rent., 220, 363 (1945).