Synthesis of Triazole Based Novel Ionic Liquids and Salts

Full text of DOI:10.1080/00304948.2017.1343037

Organic Preparations and Procedures International
The New Journal for Organic Synthesis
ISSN: 0030-4948 (Print) 1945-5453 (Online) Journal homepage: http://www.tandfonline.com/loi/uopp20
Synthesis of Triazole Based Novel Ionic Liquids and
Salts
Geetika Bhasin, Richa Srivastava & Ram Singh
To cite this article: Geetika Bhasin, Richa Srivastava & Ram Singh (2017) Synthesis of Triazole
Based Novel Ionic Liquids and Salts, Organic Preparations and Procedures International, 49:4,
370-376, DOI: 10.1080/00304948.2017.1343037
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Date: 26 August 2017, At: 06:27

Organic Preparations and Procedures International, 49:370–376, 2017
Copyright Ó Taylor & Francis Group, LLC
ISSN: 0030-4948 print / 1945-5453 online
DOI: 10.1080/00304948.2017.1343037
OPPI BRIEF
Synthesis of Triazole Based Novel Ionic Liquids
and Salts
Geetika Bhasin, Richa Srivastava, and Ram Singh
Department of Applied Chemistry, Delhi Technological University, Delhi,
1
10042, India
Ionic liquids (ILs) or organic ionic salts are composed of an organic cation and an inorganic
1
,2
ꢀ
or organic anion. Ionic salts that melt at or below 100 C are known as ionic liquids.
These molecules show exceptional properties such as low vapor pressure, liquidity over a
wide temperature range, high thermal stability, ionic conductivity, structural designability
1,2
and the ability to dissolve a wide range of chemical species. It is possible to form any
specific IL’s composition depending on one’s needs, and the desired chemical and physical
properties can be realized in a single salt, by proper selection of the component ions. Thus
the versatility of ILs arises by selecting a suitable combination of ions. ILs are prevalent in
3–6
nearly every branch of chemistry and material science, including catalysis, organic syn-
7
–9
10,11
12–15
16–19
thesis,
treatment of biomass,
The salts based on the triazolium cation have many applications including high energy
separation and analysis,
electrochemistry,
material chemistry,
pre-
20,21
22,23
energy technology,
as well as many others.
24–26
properties.
In comparison with the imidazolium cation, the triazolium cation has higher
25
nitrogen content in the heterocyclic ring, thus theoretically possessing more energy. Our
current research is focused on the development of nitrogen-rich heterocyclic energetic salts
26
that should have low vapor pressure, higher density and better thermal stability. To extend
the scope of triazolium based ILs, we have synthesized different aryl substituted, 4-amino-
1
-ethyl-3-mercapto-5-phenyl-4H-[1,2,4]triazol-1-ium salts. The synthesis of ionic liquids
and salts based on 4-amino-1,2,4-triazole has been done as shown in Schemes 1 and 2.
-Amino-5-phenyl-4H-[1,2,4]triazole-3-thiol (4) was prepared using literature meth-
4
7,28
2
ods
zoates (1) react with hydrazine hydrate to give the corresponding hydrazide derivatives
2). The formed hydrazide derivatives (2) were further treated with carbon disulfide under
starting from esters of benzoic acid and their derivatives (Scheme 1). The ben-
(
basic conditions and stirred at room temperature for 24 hours to form the corresponding
disulfide salts (3). The formed salts were then reacted with hydrazine hydrate in ethanol.
The mixture was refluxed for 8 hours to form the corresponding triazole derivatives.
Received September 23, 2016; in final form April 4, 2017.
Address correspondence to Ram Singh, Department of Applied Chemistry, Delhi Technologi-
cal University, Delhi, 110042, India. E-mail: ramsingh@dtu.ac.in
370

Synthesis of Triazole Based Novel Ionic Liquids and Salts
371
O
C
O
C
S
NHNH
2
NHNHC S K
R3
COOCH CH
2
3
N
N
N
CS , KOH
2 2
NH NH2.H O
2
R2
NH NH H O
2
2. 2
ethanol
HS
R1
R3
R
1
R
3
R
1
R
3
NH2
R1
R2
1
R
2
R
2
3
4
2
a. R =H, R =H, R =H
b. R =H, R =Br, R =H
c. R =H, R =F, R =H
1
2
3
1
2
3
1
2
3
d. R
g. R
1
=H, R
=H, R
2
=NO
2
, R
3
=H
=H
e. R
h. R
1
1
=Br, R
=H, R
2
2
=H, R
3
=H
=H
f. R
i. R
1
1
=OMe, R
2
=OMe, R
3
=OMe
1
2
=Cl, R
3
=CH , R
3
3
=H, R = OMe, R
2
3
=H
Scheme 1 Synthesis of 4-Amino-5-phenyl-4H-[1,2,4]triazole-3-thiol derivatives.
NO3
I
R3
R3
R3
R1
N
N
N
N
N
N
N
N
AgNO3
N
R
2
R2
R2
CH CH I
3
2
HS
HS
HS
NH2
R1
NH2
R
1
NH2
4
6
5
Scheme 2 Synthesis of triazolium ILs and salts.
The iodide salts (5) were prepared by quaternization of the nitrogen atom of the tria-
zole heterocycle with ethyl iodide (Scheme 2). 4-Amino-1,2,4-triazole (4) was dissolved in
hot ethanol with subsequent addition of ethyl iodide. A diverse set of organic salts was pre-
pared with combinations of cations and anions. Compounds 5(a-i) were prepared from reac-
tions of their corresponding triazole with ethyl iodide. The alkylated products were obtained
in 36-58% yield with respect to the starting benzoates (1). The synthesized compounds have
1
1
been characterized by FTIR, H NMR spectroscopy and elemental analysis. The H NMR
confirmed the alkylation at the 1-position of compounds 5. This ruled out the formation of
an isomeric product where alkylation could be possible at the -NH present at position 4. In
2
1
a typical case of 5a, the appearance of a quartet at 3.33 ppm for two protons in the H
NMR spectra confirmed the alkylation at the N-1 position which acquires a positive charge
1
after alkylation leading to the downfield shift in comparison to the usual NCH CH
H
NMR values. Also, the appearance of a broad singlet at 4.67 ppm for two protons that dis-
2
3
appeared after D O exchange further confirmed the alkylation at the 1-position.
2
The nitrate salts (6) were obtained from the corresponding iodide salts by a metathe-
sis reaction with silver nitrate (AgNO ) in water (Scheme 2). The use of water as solvent
makes this step environmentally friendly and sustainable. The products were obtained in
3
1
high yield (78-92%) and were characterized by FTIR, H NMR spectroscopy and elemen-
tal analysis (Experimental Section).
In conclusion, we have prepared a number of novel triazolium ionic liquids and salts.
Our method is suitable for the synthesis of diversified triazolium ionic liquids and salts
using environmentally friendly solvents, along with an easy work-up procedure.
Experimental Section
All commercially available solvents and reagents were used without further purifications.
IR spectra were recorded on a Thermoscientific Nicolet 380 series FTIR instrument and

3
72
Singh et al.
¡
1
the nmax values are expressed in cm . The H NMR spectra were recorded on a Bruker
1
4
00 MHz spectrometer using TMS as internal standard and the chemical shifts were
expressed in parts per million (ppm). The abbreviation s, d, t, q, m and bs stand for
singlet, doublet, triplet, quartet, multiplet and broad singlet respectively. The elemental
analyses were measured on a Perkin-Elmer 2400 instrument. Melting points have been
determined on a Thomas Hoover Unimelt capillary melting apparatus and are uncor-
rected. Thin-layer chromatography was performed on aluminium-coated silica plates pur-
chased from Merck using chloroform:methanol (9:1) as solvent.
General Procedure for the Synthesis of 4-Amino-5-phenyl-4H-[1,2,4]triazole-3-thiol
Derivatives (1)
2
7,28
Triazole derivatives were prepared according to the reported methods.
General Procedure for the Synthesis of 4-amino-1-ethyl-3-mercapto-5-phenyl-4H-
1,2,4]triazol-1-ium Iodide Derivatives (5)
[
4
-Amino-5-phenyl-4H-[1,2,4]triazole-3-thiol (4, 3.15 mmol) was dissolved and stirred in 10-
ꢀ
12 mL ethanol at 78 C upon which ethyl iodide (15.75 mmol) was added. The reaction was
ꢀ
stirred at 78 C and was monitored by thin layer chromatography until completion. After com-
pletion of reaction as shown by TLC, the reaction mixture was cooled to room temperature
whereupon water, followed by hexane, was added to the reaction mixture. The water layer
was separated and evaporated under reduced pressure to give the desired product.
4
-Amino-1-ethyl-3-mercapto-5-phenyl-4H-[1,2,4]triazol-1-ium
ꢀ
iodide
(5a):
Yield: (40%); Mp.: 150 C; IR (KBr): 3290, 1673, 1652, 1600, 1581, 1519, 1484, 1384,
¡
1 1
350, 1277, 1196, 908, 754, 692, 653 cm ; H NMR (CDCl ): d 1.50 (3H, t, CH ), 2.43
1
3
3
(
(
1H, s, SH), 3.33 (2H, q, CH ), 4.67 (2H, bs, NH ), 7.49 (1H, d, J D 7.2 Hz, Ar-H), 7.53
2
2
2H, m, Ar-H), 7.95 (2H, m, Ar-H).
Anal. Calcd for C H IN S: C, 34.49; H, 3.76; N, 16.09; S, 9.21. Found: C, 34.78;
1
0
13
4
H, 3.77; N, 16.35; S, 9.37.
-Amino-1-ethyl-3-mercapto-5-(4-bromophenyl)-4H-[1,2,4]triazol-1-ium iodide
4
5b): Yield: (45%); Mp.: 156-158 C; IR (KBr): 3500, 1828, 1614, 1403, 1384, 1072,
ꢀ
(
¡
1
010, 968, 826, 725, 586, 495 cm ; H NMR (CDCl ): d 1.47 (3H, t, CH ), 1.84 (1H, s,
1
1
3
3
SH), 3.31 (2H, q, CH ), 4.70 (2H, bs, NH ), 7.59 (2H, d, J D 6.8 Hz, Ar-H), 7.98 (2H, d,
2
2
J D 6.6 Hz, Ar-H).
Anal. Calcd for C H BrIN S: C, 28.12; H, 2.83; N, 13.12; 7.51. Found: C, 28.26;
1
0
12
4
H, 2.81; N, 13.23; S, 7.59.
-Amino-1-ethyl-3-mercapto-5-(4-fluorophenyl)-4H-[1,2,4]triazol-1-ium iodide
5c): Yield: (36%); Viscous liquid; IR (KBr): 3300, 1807, 1600, 1499, 1387, 1324, 1260,
4
(
1
¡
123, 1090, 957, 764, 563 cm ; HNMR (CDCl ): d 1.50 (3H, t, CH ), 3.36 (2H, q,
3 3
1 1
CH ), 3.96 (2H, bs, NH ), 5.46 (1H, bs, SH), 7.87 (2H, d, J D 6.9 Hz, Ar-H), 8.18 (2H, d,
2
2
J D 6.8 Hz, Ar-H).
Anal. Calcd for C H FIN S: C, 32.80; H, 3.30; N, 15.30; S, 8.76. Found: C, 32.85;
1
0
12
4
H, 3.29; N, 15.48; S, 8.80.
-Amino-1-ethyl-3-mercapto-5-(4-nitrophenyl)-4H-[1,2,4]triazol-1-ium iodide
5d): Yield: (36%); Viscous liquid; IR (KBr): 3500, 1835, 1677, 1465, 1377, 1354, 1277,
4
(
1
¡
167, 1067, 983, 769, 546, 439, 393 cm ; HNMR (CDCl ): d 1.47 (3H, t, CH ), 1.95
3 3
1 1
(
(
1H, bs, SH), 3.32 (2H, q, CH ), 4.76 (2H, bs, NH ), 7.46 (2H, d, J D 8.4 Hz, Ar-H), 8.08
2
2
2H, d, J D 9 Hz, Ar-H).

Synthesis of Triazole Based Novel Ionic Liquids and Salts
373
Anal. Calcd for C H IN O S: C, 30.55; H, 3.08; N, 17.81; S, 8.15. Found: C, 30.61;
1
0
12
5 2
H, 3.07; N, 17.88; S, 8.19.
4
5e): Yield: (48%); Mp.: 102-105 C; IR (KBr): 3490, 1622, 1476, 1384, 909, 803, 784,
-Amino-1-ethyl-3-mercapto-5-(3-bromophenyl)-4H-[1,2,4]triazol-1-ium iodide
ꢀ
(
¡
1 1
10, 682, 468, 427 cm ; HNMR (CDCl ): d 1.30 (3H, t, CH ), 1.73 (1H, bs, SH), 3.32
7
3
3
(2H, q, CH ), 4.71 (2H, bs, NH ), 7.67 (1H, m, Ar-H), 8.04 (1H, m, Ar-H), 7.76 (1H, m,
2 2
Ar-H), 8.04 (1H, m, Ar-H).
Anal. Calcd for C H BrIN S: C, 28.12; H, 2.83; N, 13.12; S, 7.51. Found: C, 28.24;
1
0
12
4
H, 2.81; N, 13.25; S, 7.60.
-Amino-1-ethyl-3-mercapto-5-(3,4,5-trimethoxyphenyl)-4H-[1,2,4]triazol-1-
ium iodide (5f): Yield: (37%); Viscous liquid; IR (KBr): 3390, 1690, 1455, 1370, 1320,
4
¡
266, 1198, 977, 810, 756, 692, 572, 496, 433 cm ; HNMR (CDCl ): d 1.48 (3H, t,
3
1 1
1
CH ), 3.31 (2H, q, CH ), 3.94-4.01 (9H, m, OCH ), 5.49 (2H, bs, NH ), 7.28 (2H, m, Ar-
3
2
3
2
H).
Anal. Calcd for C H IN O S: C, 35.63; H, 4.37; N, 12.78; S, 7.32. Found: C, 35.70;
1
3
19
4 3
H, 4.35; N, 12.80; S, 7.38.
4
5g): Yield: (55%); Mp.: 160-165 C; IR (KBr): 3241, 1638, 1570, 1473, 1452, 1333,
-Amino-1-ethyl-3-mercapto-5-(4-chlorophenyl)-4H-[1,2,4]triazol-1-ium iodide
ꢀ
(
¡
1 1
285, 1241, 1113, 1094, 836, 787, 730, 686, 539, 486 cm ; HNMR (CDCl ): d 1.47
1
3
(3H, t, CH ), 1.92 (1H, bs, SH), 3.31 (2H, q, CH ), 4.74 (2H, bs, NH ), 7.44 (2H, d,
3 2 2
J D 8.4 Hz, Ar-H), 8.06 (2H, d, J D 9.2 Hz, Ar-H).
Anal. Calcd for C H ClIN S: C, 31.39; H, 3.16; N, 14.64; S, 8.38. Found: C, 31.42;
1
0
12
4
H, 3.15; N, 14.68; S, 8.40.
-Amino-1-ethyl-3-mercapto-5-(4-methylphenyl)-4H-[1,2,4]triazol-1-ium iodide
5h): Yield: (50%); Viscous liquid; IR (KBr): 3233, 1623, 1576, 1462, 1370, 1265, 1100,
4
(
¡
088, 756, 708, 630, 500 cm ; HNMR (CDCl ): d 1.21 (3H, t, CH ), 2.80 (3H, s, CH ),
3 3 3
1 1
1
3
8
.26 (2H, q, CH ), 4.95 (1H, bs, SH), 5.69 (2H, bs, NH ), 7.72 (2H, d, J D 6 Hz, Ar-H),
2
2
.00 (2H, d, J D 6.4 Hz, Ar-H).
4
Anal. Calcd for C H IN S: C, 36.47; H, 4.17; N, 15.47; S, 8.85. Found: C, 36.50;
1
1
15
H, 4.15; N, 15.49; S, 8.89.
4
iodide (5i): Yield: (58%); Mp.: 78-79 C; IR (KBr): 3461, 1607, 1442, 1384, 1312, 1256,
-Amino-1-ethyl-3-mercapto-5-(4-methoxyphenyl)-4H-[1,2,4]triazol-1-ium
ꢀ
¡
1 1
183, 1027, 836, 732, 693, 636, 525 cm ; HNMR (CDCl ): d 1.48 (3H, t, CH ), 1.93
1
3
3
(1H, bs, SH), 3.32 (2H, q, CH ), 3.87 (3H, s, OCH ), 4.75 (2H, s, NH ), 7.45 (2H, d,
2 3 2
J D 8.4 Hz, Ar-H), 8.07 (2H, d, J D 9 Hz, Ar-H).
Anal. Calcd for C H IN OS: C, 34.93; H, 4.00; N, 14.81; S, 8.48. Found: C, 34.98;
4
1
1
15
H, 3.99; N, 14.83; S, 8.52.
General Procedure for the Synthesis of 4-amino-1-ethyl-3-mercapto-5-phenyl-4H-
1,2,4]triazol-1-ium Nitrate Derivatives (6)
[
4
-Amino-1-ethyl-3-mercapto-5-phenyl-4H-[1,2,4]triazol-1-ium iodide derivatives
5, 10 mmol) were dissolved in 15 mL distilled water. While stirring, a solution of
0 mmol of silver nitrate in 10 mL distilled water was added drop-wise. The pale
(
1
yellow suspension was stirred for 30 minutes, filtered and rinsed with 10 mL dis-
tilled water. The water portion was removed under reduced pressure to produce the
desired nitrate salt (6).
4-Amino-1-ethyl-3-mercapto-5-phenyl-4H-[1,2,4]triazol-1-ium nitrate (6a):
Yield: (91%); Viscous liquid; IR (KBr): 3300, 1660, 1678, 1600, 1589, 1525, 1484, 1384,

3
74
Singh et al.
¡
1 1
348, 1277, 1200, 915, 833, 754, 690, 651 cm ; HNMR (CDCl ): d 1.53 (3H, t, CH ),
1
3
3
2.51 (1H, s, SH), 3.36 (2H, q, CH ), 4.70 (2H, bs, NH ), 7.49 (1H, m, Ar-H), 7.55 (2H,
2 2
m, Ar-H), 7.98 (2H, m, Ar-H).
Anal. Calcd for C H N O S: C, 42.39; H, 4.63; N, 24.72; S, 11.32. Found: C,
0 13 5 3
1
4
2.41; H, 4.64; N, 24.76; S, 11.38.
-Amino-1-ethyl-3-mercapto-5-(4-bromophenyl)-4H-[1,2,4]triazol-1-ium nitrate
6b): Yield: (89%); Viscous liquid; IR (KBr): 3515, 1890, 1652, 1415, 1385, 1355, 1077,
4
(
¡
010, 969, 826, 833, 799, 725, 586, 499 cm ; HNMR (CDCl ): d 1.50 (3H, t, CH ),
3 3
1 1
1
2
7
.23 (1H, s, SH), 3.33 (2H, q, CH ), 4.76 (1H, bs, NH ), 7.50 (2H, d, J D 6.4 Hz, Ar-H),
2
2
.96 (2H, d, J D 6.6 Hz, Ar-H).
Anal. Calcd for C H BrN O S: C, 33.16; H, 3.34; N, 19.34; S, 8.85 found: C,
5 3
1
0
12
3
3.22; H, 3.33; N, 19.37; S, 8.94.
-Amino-1-ethyl-3-mercapto-5-(4-fluorophenyl)-4H-[1,2,4]triazol-1-ium nitrate
6c): Yield: (92%); Viscous liquid; IR (KBr): 3320, 1816, 1620, 1499, 1389, 1355, 1324,
4
(
¡
263, 1128, 1090, 960, 804, 739, 764, 567 cm ; HNMR (CDCl ): d 1.54 (3H, t, CH ),
3 3
1 1
1
3
8
.38 (2H, q, CH ), 3.70 (2H, bs, NH ), 5.50 (1H, bs, SH), 7.88 (2H, d, J D 6.6 Hz Ar-H),
2
2
.20 (2H, d, J D 6.8 Hz, Ar-H).
5 3
Anal. Calcd for C H FN O S: C, 39.86; H, 4.01; N, 23.24; S, 10.64. Found: C,
1
0
12
3
9.90; H, 4.00; N, 23.28; S, 10.70.
-Amino-1-ethyl-3-mercapto-5-(4-nitrophenyl)-4H-[1,2,4]triazol-1-ium nitrate
6d): Yield: (78%); Viscous liquid; IR (KBr): 3510, 1838, 1680, 1470, 1377, 1354, 1277,
4
(
1
¡
180, 1067, 990, 840, 769, 731, 546, 441, 392 cm ; HNMR (CDCl ): d 1.49 (3H, t,
3
1 1
CH ), 1.98 (1H, bs, SH), 3.33 (2H, q, CH ), 4.79 (2H, bs, NH ), 7.50 (2H, d, J D 8.2 Hz,
3
2
2
Ar-H), 8.10 (2H, d, J D 9.0 Hz, Ar-H).
Anal. Calcd for C H N O S: C, 36.58; H, 3.68; N, 25.60; S, 9.77. Found: C, 36.65;
1
0 12 6 5
H, 3.65; N, 25.66; S, 9.79.
-Amino-1-ethyl-3-mercapto-5-(3-bromophenyl)-4H-[1,2,4]triazol-1-ium nitrate
6e): Yield: (90%); Viscous liquid; IR (KBr): 3500, 1644, 1478, 1355, 1390, 955, 805,
4
(
7
¡
85, 740, 712, 691, 472, 429 cm ; HNMR (CDCl ): d 1.39 (3H, t, CH ), 1.77 (1H, bs,
3 3
1 1
SH), 3.35 (2H, q, CH ), 4.75 (2H, bs, NH ), 7.69 (1H, m, Ar-H), 7.70 (1H, m, Ar-H),
2
2
7
.78 (1H, m, Ar-H), 8.09 (1H, m, Ar-H).
Anal. Calcd for C H BrN O S: C, 33.16; H, 3.34; N, 19.34; S, 8.85. Found: C,
1
0
12
5 3
3
3.25; H, 3.33; N, 19.39; S, 8.90.
-Amino-1-ethyl-3-mercapto-5-(3,4,5-trimethoxyphenyl)-4H-[1,2,4]triazol-1-
ium nitrate (6f): Yield: (79%); Viscous liquid; IR (KBr): 3394, 1696, 1460, 1348, 1378,
4
¡
320, 1269, 1200, 977, 811, 766, 739, 698, 579, 496, 437 cm ; HNMR (CDCl ): d 1.49
3
1 1
1
(3H, t, CH ), 3.35 (2H, q, CH ), 3.98-4.01 (9H, m, OCH ), 5.5 (2H, bs, NH ), 7.30 (2H,
m, Ar-H).
3 2 3 2
Anal. Calcd for C H N O S: C, 41.82; H, 5.13; N, 18.76; S, 8.59. Found: C, 41.93;
1
3 19 5 6
H, 5.11; N, 18.84; S, 8.58.
-Amino-1-ethyl-3-mercapto-(4-chlorophenyl)-4H-[1,2,4]triazol-1-ium nitrate
6g): Yield: (92%); Viscous liquid; IR (KBr): 3255, 1640, 1575, 1473, 1452, 1349, 1335,
4
(
1
¡
285, 1244, 1120, 1096, 836, 790, 730, 688, 541, 495 cm ; HNMR (CDCl ): d 1.48
3
1 1
(3H, t, CH ), 1.99 (1H, bs, SH), 3.36 (2H, q, CH ), 4.8 (2H, bs, NH ), 7.47 (2H, d,
3 2 2
J D 8 Hz, Ar-H), 8.09 (2H, d, J D 9.0 Hz, Ar-H).
Anal. Calcd for C H ClN O S: C, 37.80; H, 3.81; N, 22.04; S, 10.09. Found: C,
1
0
12
5 3
3
7.85; H, 3.77; N, 22.07; S, 10.11.
-Amino-1-ethyl-3-mercapto-5-(4-methylphenyl)-4H-[1,2,4]triazol-1-ium nitrate
6h): Yield: (91%); viscous; IR (KBr): 3272, 1629, 1578, 1463, 1377, 1359, 1265, 1104,
4
(

Synthesis of Triazole Based Novel Ionic Liquids and Salts
375
¡
1 1
090, 758, 710, 630, 505 cm ; HNMR (CDCl ): d 1.34 (3H, t, CH ), 2.87 (3H, s, CH ),
1
3
8
3
3
3
.29 (2H, q, CH ), 4.99 (1H, bs, SH), 6.00 (2H, bs, NH ), 7.74 (2H, d, J D 6.4 Hz, Ar-H),
2
2
.04 (2H, d, J D 6.8 Hz, Ar-H).
1 15 5 3
Anal. Calcd for C H N O S: C, 44.43; H, 5.08; N, 23.55; S, 10.78. Found: C,
1
4
4.49; H, 5.07; N, 23.59; S, 10.82.
-Amino-1-ethyl-3-mercapto-5-(4-methoxyphenyl)-4H-[1,2,4]triazol-1-ium
nitrate (6i): Yield: (92%); viscous; IR (KBr): 3477, 1615, 1455, 1384, 1353, 1315, 1263,
4
¡
185, 1029, 837, 732, 694, 636, 533 cm ; HNMR (CDCl ): d 1.52 (3H, t, CH ), 1.95
3 3
1 1
1
(1H, bs, SH), 3.35 (2H, q, CH ), 3.91 (3H, s, OCH ), 4.78 (2H, s, NH ), 7.48 (2H, d,
2 3 2
J D 8.0 Hz, Ar-H), 8.09 (2H, d, J D 8.8 Hz, Ar-H).
Anal. Calcd for C H N O S: C, 42.17; H, 4.83; N, 22.35; S, 10.23. Found: C,
1 15 5 4
1
4
2.22; H, 4.81; N, 22.39; S, 10.25.
Acknowledgments
The authors are thankful to HEMRL Pune and CSIR, New Delhi, for financial support.
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