A novel and convenient synthesis of 3-amino-2H-1,2,4-triazoles from isoselenocyanates and hydrazine hydrate

Article abstract of DOI:10.3184/174751918X15260518865352

A novel and convenient one-pot synthesis of 3-amino-2H-1,2,4-triazoles from two molecules of isoselenocyanates and hydrazine hydrate via cyclodeselenisation was developed. Various 3-amino-2H-1,2,4-triazoles were obtained in moderate to good yields (33-45%

Full text of DOI:10.3184/174751918X15260518865352

JOURNAL OF CHEMICAL RESEARCH 2018
VOL. 42 MAY, 255–259
RESEARCH PAPER 255
A novel and convenient synthesis of 3-amino-2H-1,2,4-triazoles from
isoselenocyanates and hydrazine hydrate
Xue Lia*, Zhixiang Penga, Yuanyuan Zhanga, Jiangwei Wanga, Bin Ganb and Yuanyuan Xieb
aDrug Research Center, Traditional Chinese Medicine Institute of Jiangxi, Nanchang 330046, P.R. China
bCollaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, P.R. China
A novel and convenient one-pot synthesis of 3-amino-2H-1,2,4-triazoles from two molecules of isoselenocyanates and hydrazine hydrate
via cyclodeselenisation was developed. Various 3-amino-2H-1,2,4-triazoles were obtained in moderate to good yields (33–45%, based on
isoselenocyanates). The selenium powder and aromatic amine side products during the reaction could be recycled for efficient preparation
of isoselenocyanates, which improved the atom economy. A plausible mechanism was proposed for the formation of the target products.
Keywords: isoselenocyanates, selenoureas, hydrazine hydrate, 3-amino-2H-1,2,4-triazoles
On account of their unique structures and reactivities, 3-amino-
2H-1,2,4-triazoles are widely utilised as intermediates to
prepare various biologically important compounds, such
as hypoglycemic agents,1 [1,2,4]triazolo[1,5-a]pyrimidine
bioactive derivatives,2 tumour inhibitors3–6 and selective
inhibitors of TYK2 and JAK1 over JAK2 and JAK3.7
1,2,4-Triazoles have an electron-rich bioisosteric ring that
can mimic bioactive heterocyclic nuclei, such as imidazole,8
pyrazole9 and thiazole.10,11 The wide-ranging applications
of 3-amino-2H-1,2,4-triazoles have attracted considerable
attention in synthesis. Although numerous procedures for
the synthesis of 1,2,4-triazoles with various substituents have
been reported, few studies have described the direct synthesis
of 3-N-substituted-1,2,4-triazoles and 5-unsubstituted-1,2,4-
triazoles. Over the past 50 years, the most widely used methods
for the synthesis of 3-amino-2H-1,2,4-triazoles have involved
the reaction of hydrazine hydrate with various cyanamides, such
as N-cyanoethanimidothioates12,13 and N-cyanoimidates,14–16 and
the reaction of amines with hydrazonitrile derivates, such as
N′-cyanobenzohydrazides.17,18 However, the substrates used in
the above methods require cyanides, which are obtained from
hypertoxic cyanogen chloride/bromide reacting with amines,
imide or hydrazine salts.19–21 To avoid using cyanides, Chorev et
al.22 described the preparation of 3-amino-1,2,4-triazoles from
the reaction of 1,3-disubstituted-thioureas and acyl hydrazide
with toxic Hg(OAc)2 as a thiophilic reagent. On this basis, Guin
et al.23 have envisaged a strategy for the synthesis of 3-amino-
1,2,4-triazoles from 1,3-disubstituted thioureas and formic
hydrazide using hypotoxic molecular iodine as the desulfurising
agent. Nevertheless, these methods suffer from environmental
concerns as they directly or indirectly utilise hypertoxic or
hypotoxic reagents, high reaction temperatures and tedious
manipulative procedures, which impede the applicability of
these methodologies.
of 3-amino-2H-1,2,4-triazoles from two molecules of
isoselenocyanates and hydrazine hydrate via cyclodeselenisation
(Scheme 1). Without any harsh reagent, such as a deselenisation
or cyclisation reagent, various 3-amino-2H-1,2,4-triazoles
were constructed in moderate to good yields (33–45%, based
on isoselenocyanates 1). The selenium powder and aromatic
amine byproducts during the reactions could be recycled to
prepare the corresponding isoselenocyanates efficiently, which
improved the atom economy.
Results and discussion
Phenyl selenourea 2a,27,28 which was obtained by phenyl
isoselenocyanate reacting with aqueous ammonia at room
temperature, was selected to optimise the reaction conditions
to form 3-(phenylamino)-2H-1,2,4-triazole 3a. First, we
investigated the effects of different solvents, reaction
temperatures and the amount of hydrazine hydrate. The results
are summarised in Table 1. Among the solvents, MeOH proved
to be optimal as 28% yield could be obtained, which may be
due to the solubility, stability and reactivity of selenourea (Table
1, entries 1–5). The reaction proceeded best at 50 °C (Table 1,
entries 6, 9 and 12). As both 2a and 3a might have low stability
at 60 °C, the yield of 3a declined at this temperature (Table 1,
entries 11 and 12). Prolonged reaction times at 40 °C did not
enhance the yield (Table 1, entries 6 and 7). A reaction time
of 12 h gave the best yield (Table 1, entries 8–10). To further
improve the yield of 3a, the amount of hydrazine hydrate was
investigated (Table 1, entries 9, 13 and 16). The yield was
improved to 42% by increasing the amount of hydrazine hydrate
to 2.0 equiv. (Table 1, entry 9). In addition, the recovery yields
of Se powder and 4a were up to 88% and 40%, respectively
(Table 1, entry 14). Therefore, the optimal reaction conditions
were established as using 2.0 equiv. of hydrazine hydrate,
MeOH as solvent, a reaction temperature of 50 °C and about
12 h reaction time.
Isoselenocyanates are widely employed in the synthesis
of nitrogen-containing heterocycles due to their convenient
preparation, low toxicity, relative stability and excellent
reactivity.24–26 We have been interested in the synthesis
of 1,2,4-triazoles and consequently, we have developed
unexpectedly a novel and convenient one-pot synthesis
With the optimised conditions, we set out to explore the
substrate scope. In a one-pot procedure, various aromatic
selenoureas 2 were obtained by isoselenocyanates 1 reacting
with aqueous ammonia in CH2Cl2 and then further reacting
with hydrazine hydrate to form the corresponding triazoles
R
HN
H
N
.
.
N
NH2
Se NH3 H2O
NH2NH2 H2O
+ 2Se + R-NH2
2
R
2
R
C
N
N
H
N
Se
3
4
2
1
Scheme 1 Preparation of 3-amino-2H-1,2,4-triazoles from isoselenocyanates and hydrazine hydrate.
* Correspondent. E-mail: m18702635626@163.com

256 JOURNAL OF CHEMICAL RESEARCH 2018
Table 1 Optimisation of reaction conditions for the conversion of selenoureas to 3-amino-2H-1,2,4-triazoles
NH2
Se
NH2
N
solvent, temp.
+
+
+
N
2Se
NH2NH2
H
2O
2
N
H
N
N
H
H
4a
3a
2a
Aqueous NH2NH2
(50%, equiv.)
Temperature
(oC)
Yield
Entry
Solvent
Time (h)a
(3a, %)b
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
H2O
CH2Cl2
DMF
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.0
2.0
2.5
3.0
25
25
25
25
25
40
40
50
50
50
60
60
50
50
50
50
20
20
20
16
16
12
24
8
12
16
8
12
12
12
12
12
<5
10
15
20
28
30
28
35
38
36
26
25
29
EtOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
MeOH
42, 95c, 40d
40
41
aMonitored by TLC.
bIsolated yield based on 2a.
cRecovery yield of Se powder based on 2a.
dRecovery yield of 4a based on 2a.
Table 2 One-pot synthesis of 3-amino-2H-1,2,4-triazoles from isoselenocyanates and hydrazine hydrate
R
HN
H
N
N
.
.
H
2O
NH2
NH3
H
Se
2O
NH2NH2
+ 2Se + R-NH2
2
R
2
R
C
N
N
H
N
MeOH, 50oC
CH2Cl2, r.t.
Se
3
4
2
1
Entry
Reactant
R
C6H5
Producta
Yield (%)b
40,34c
37
41
45,38c
36
1
2
3
4
5
6
7
1a
1b
1c
1d
1e
1f
3a
3b
3c
3d
3e
3f
2-CH3C6H4
3-CH3C6H4
4-CH3C6H4
3-BrC6H4
4-FC6H4
α-Naphthyl
39
33
1g
3g
3h
8
1h
36
N
H
F
3C
O
N
C
S
Se
F
3C
O
N
S
N
HN
aConfirmed by IR, 1H and 13C NMR, MS-ESI, HRMS-ESI.
bIsolated yield based on isoselenocyanates 1.
cUsing isoselenocyanates produced from recycled byproducts.
3 in MeOH at 50 °C. The results are summarised in Table 2.
A variety of 3-amino-2H-1,2,4-triazoles were constructed in
moderate to good yields ranging from 33 to 45% (based on
isoselenocyanates 1).The nature of the R group affected the
reaction yields to some extent. Compounds substituted with an
electron donating group (Table 2, entries 2–4) showed higher
yields than compounds substituted with an electron withdrawing
group (Table 2, entries 3 and 5). When substituents were
attached to the ortho position of the phenyl isoselenocyanate
(Table 2, entries 1–4), the reaction yields decreased slightly
due to steric effects. Naphthyl- and macroradical-substituted
isoselenocyanates also provided the desired product in moderate
yield — 33% and 36%, respectively (Table 2, entries 7 and 8).
Furthermore, 3-amino-2H-1,2,4-triazoles were still obtained in
satisfactory yields using isoselenocyanates produced from the
recycled byproducts (Table 2, entries 1 and 4).
1
According to the H NMR spectra of 3a, we could confirm
that the C–H signal of triazole appeared as a singlet at around δ
8.25 ppm. Furthermore, according to the 1H–1H COSY spectra
of 3a, the C–H signal of triazole was not correlative to N–H.
Therefore, the triazoles could be assigned as 3-amino-2H-1,2,4-
triazoles 3, not 1H isomers 5 or 6 (Scheme 2).

JOURNAL OF CHEMICAL RESEARCH 2018 257
(
H
)
δ H = 8.24ppm
H
H
H
N
N
N
R
R
R
N
N
N
N
N
H
N
N
N
N
H
H
H
H
6
5
(
)
3
δ H = 13.23ppm
Scheme 2
H
.
aq NH3
N
NH2
Se
Se
R
R
C
N
2
1
e
S
H NH
N
R
2 H
N
H
N
H
H2N
N
.
NH
aq NH2NH2
N
NH2
R
2 H
N
R
H
R
N
R
N
SeH
H
NH2
H
Se
Se
SeH
8
NH3
2
1 2
/ O2
7
Se + H2O
Se + H2O 1/4O2
H
N
SeH
Se
H
NH2
R
HN
R
N
N
R
H
H
HN
R
N
N
N
N
N
N
N
H
R
N
N
H
N
H
N
H
Se
R-NH2
3
11
10
9
4
Scheme 3 Plausible mechanism proposed for the formation of 3.
HCOOH, BTC, Et3N
Scheme 4 Recovery and recycling of selenium powder and aromatic amines 4.
A plausible mechanism is proposed for the formation of
3-amino-2H-1,2,4-triazoles 3 in Scheme 3. First, selenourea 2
is generated from isoselenocyanate 1 and aqueous ammonia
rapidly and efficiently, and then reacts with hydrazine hydrate
to form intermediates 7. Subsequently, intermediate 7 attacks
another selenourea 2 to form intermediate 8 via sloughing
ammonia. Intermediate 8 is converted to intermediate 9
via deselenisation with the aid of oxygen. Afterwards, the
intramolecular cyclisation of 9 produces the intermediate 10
and the byproduct aromatic amine 4. Finally, intermediate
10 tended to transform to the resonance forms 1,2,4-triazoles
11, which converted to the target products 3-amino-2H-1,2,4-
triazoles 3 via deselenisation with the aid of oxygen. To prove
these processes, the reactions were carried out in a nitrogen-
protected vessel — no desired product or selenium powder
were detected, which meant that oxygen was significant to
the reaction. Further discussion can be found in our previous
paper.29
After reaction completion, the precipitated selenium powder
was easily obtained by filtering, washed with CH2Cl2 and
reused for the preparation of isoselenocyanates. The filtrate was
concentrated under vacuum, and then the residue was dissolved
in ethyl acetate and precipitated by adding petroleum ether.
Most aromatic amines 4 were found in petroleum ether and
obtained easily by filtering and concentrating under vacuum.
Afterwards, selenium powder and aromatic amines 4 could
be recycled to prepare the corresponding isoselenocyanates
efficiently by reacting with HCOOH and bis(trichloromethyl)
carbonate under base,27 which improved the atom economy
(Scheme 4 and Table 2, entries 1 and 4).

258 JOURNAL OF CHEMICAL RESEARCH 2018
Conclusion
(KBr) (νmax cm−1): 3118, 2917, 1598, 1553, 1514, 1450, 1250, 1048, 979,
821, 794; 1H NMR (400 MHz, DMSO-d6): δ 13.08 (s, 1H, NH), 8.86 (s,
1H, NH), 8.18 (s, 1H, N=CH), 7.37 (d, J = 8 Hz, 2H, ArH), 6.94 (d, J =
8 Hz, 2H, ArH), 2.19 (s, 3H, CH3).
A novel and convenient one-pot synthesis of 3-amino-2H-
1,2,4-triazoles was developed starting from two molecules of
isoselenocyanates and hydrazine hydrate via cyclodeselenisation
in moderate to good yields. The procedure obviates using any
harsh reagent, such as a deselenisation or cyclisation reagent.
Luckily, both selenium powder and aromatic amines 4 are
byproducts during the reactions that could be easily recovered
and reused to achieve the economic and ecofriendly synthesis
of 3-amino-2H-1,2,4-triazoles.
3-[(3-Bromophenyl)amino]-2H-1,2,4-triazole (Table 2, 3e): Light
yellow solid; yield 0.171 g (36%); m.p. 180–182 °C; IR (KBr) (νmax
cm−1): 3129, 2935, 1618, 1593, 1556, 1469, 1298, 1249, 1074, 981, 775,
751; 1H NMR (400 MHz, DMSO-d6): δ 13.33 (s, 1H, NH), 9.38 (s, 1H,
NH), 8.32 (s,1H, N=CH), 7.89–7.88 (m, 1H, ArH), 7.45–7.42 (m, 1H,
ArH), 7.16–7.12 (m, 1H, ArH), 6.93–6.91 (m, 1H, ArH); 13C NMR
(100 MHz, DMSO-d6): δ 159.6, 143.6, 142.0, 130.3, 121.7, 121.0, 117.4,
114.4; MS (ESI) m/z (%): 239.0 ([M(C8H779BrN4) + H]+, 100%), 241.0
([M(C8H781BrN4) + H]+, 97%). HRMS (ESI) calcd for C8H879BrN4 [M +
H]+: 238.9932; found: 238.9940. HRMS (ESI) calcd for C8H881BrN4 [M
+ H]+: 240.9912; found: 240.9920.
Experimental
Infrared spectra were determined on
a Nicolet Avatar-370
spectrometer in KBr (ν in cm−1). Melting points were measured on
a Büchi B-540 capillary melting point apparatus and uncorrected.
Mass spectra (ESI-MS) were determined on a Thermo Finnigan
LCQ-Advantage. High-resolution mass spectra (ESI-HRMS)
were determined on an Agilent 6210 TOF instrument. 1H NMR
and 13C NMR spectra were recorded on Varian Mercury Plus-400
spectrometer (400 and 100 MHz), δ in parts per million, J in Hertz,
using TMS as internal standard.
3-[(4-Fluorophenyl)amino]-2H-1,2,4-triazole (Table 2, 3f): Light
brown solid; yield 0.139 g (39%); m.p. 197–198 °C; IR (KBr) (νmax
1
cm−1): 3285, 2920, 1573, 1540, 1507, 1232, 1211, 980, 836; H NMR
(400 MHz, DMSO-d6): δ 13.23 (s, 1H, NH), 9.10 (s, 1H, NH), 8.26
(s, 1H, N=CH), 7.55–7.52 (m, 2H, ArH), 7.05–7.01 (m, 2H, ArH);
13C NMR (100 MHz, DMSO-d6): δ 160.1, 155.4 (1JCF = 232 Hz), 141.8,
138.6, 116.5, 114.7; MS (ESI) m/z (%): 179.3 ([M + H]+, 100%). HRMS
(ESI) calcd for C8H8FN4 [M + H]+: 179.0732; found: 179.0727.
3-[(α-Naphthyl)amino]-2H-1,2,4-triazole (Table 2, 3g): Golden
yellow solid; yield 0.138 g (33%); m.p. 200–202 °C; IR (KBr) (νmax
cm−1): 3210, 3173, 1675, 1634, 1584, 1529, 1479, 1402, 1344, 1258;
1H NMR (400 MHz, DMSO-d6): δ 13.34 (s, 1H, NH), 8.93 (s, 1H,
NH), 8.38–8.35 (m, 1H, ArH), 8.02 (s,1H, N=CH), 7.84 (s, 1H, ArH),
7.47–7.39 (m, 5H, ArH); 13C NMR (100 MHz, DMSO-d6): δ 160.5,
142.0, 137.5, 133.7, 127.8, 125.8, 125.7, 125.5, 124.6, 121.9, 119.7, 111.7;
MS (ESI) m/z (%): 211.4 ([M + H]+, 100%). HRMS (ESI) calcd for
C12H11N4 [M + H]+: 211.0984; found: 211.0982.
3-({3-Methyl-4-[4-(trifluoromethylthio)phenoxy]phenyl}amino)-
2H-1,2,4-triazole (Table 2, 3h): Golden yellow solid; yield 0.243 g
(36%); m.p. 202–203 °C; IR (KBr) (νmax cm−1): 3290, 2928, 1619, 1554,
1487, 1241, 1151, 1122, 1087, 835; 1H NMR (400 MHz, DMSO-d6): δ
13.24 (s, 1H, NH), 9.14 (s, 1H, NH), 8.27 (s, 1H, N=CH), 7.64–7.62
(m, 2H, ArH), 7.52 (s, 1H, ArH), 7.44–7.42 (m, 1H, ArH), 6.95–6.91
(m, 3H, ArH), 2.05 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6): δ
160.9, 144.2, 142.0, 138.2, 130.9, 129.8 (1JCF = 305 Hz), 129.7, 127.8,
121.4, 118.1, 116.5, 114.7, 114.2, 16.0; MS (ESI) m/z (%): 367.2 ([M +
H]+, 100%). HRMS (ESI) calcd for C16H14F3N4OS [M + H]+: 367.0840;
found: 367.0845.
Synthesis of 3-amino-2H-1,2,4-triazoles 3a–h (3a selected as
example); general procedure
Phenyl isoselenocyanate 1a (0.364 g, 2 mmol) and aqueous ammonia
(25%, 0.336 g, 2.4 mmol) were added to CH2Cl2 (3 mL) with magnetic
stirring for 30 min at room temperature. Phenyl selenourea 1a was
confirmed by TLC. The reaction mixture was concentrated under
vacuum to remove CH2Cl2, then hydrazine hydrate (50%, 0.400 g,
4 mmol) and MeOH (10 mL) were added and stirred for about 12 h at
50 °C. Selenium powder precipitated out gradually. After reaction
completion, selenium powder was filtered off and washed with CH2Cl2
(20 mL). The recovery rate of selenium powder was about 90% (0.143 g,
based on 1a). The filtrate was concentrated under vacuum, and the
residue was dissolved in ethyl acetate (7 mL) and precipitated by
adding petroleum ether (5 mL). Most of phenylamine 4a was found in
petroleum ether and obtained easily by filtering and concentrating under
vacuum with 38% recovery yield (0.071 g, based on 1a). The residue was
purified through column chromatography on silica gel (CH2Cl2/MeOH =
8:1–4:1) to give the pure product 3-(phenylamino)-2H-1,2,4-triazole 3a.
3-(Phenylamino)-2H-1,2,4-triazole (Table 2, 3a): Light brown solid;
yield 0.128 g (40%, based on 1a); m.p. 175–176 °C (lit.12 175–178 °C);
IR (KBr) (νmax cm−1): 3146, 2913, 1609, 1573, 1558, 1500, 1458, 1241,
977, 748; 1H NMR (400 MHz, DMSO-d6): δ 13.23 (s, 1H, NH), 9.07 (s,
1H, NH), 8.26 (s, 1H, N=CH), 7.53–7.51 (m, 2H, ArH), 7.19–7.18 (m,
2H, ArH), 6.74 (s, 1H, ArH); 13C NMR (100 MHz, DMSO-d6): δ 160.0,
142.0, 141.7, 1128.5, 118.8, 115.4.
Synthesis of {3-Methyl-4-[4-(trifluoromethylthio)phenoxy]phenyl}
isoselenocyanate (Table 2, 1h)
Compound
1h
was
prepared25
from
{3-methyl-4-[4-
(from Guobang
3-[(2-Methylphenyl)amino]-2H-1,2,4-triazole (Table 2, 3b): White
solid; yield 0.129 g (37%); m.p. 168–169 °C; IR (KBr) (νmax cm−1): 3101,
3056, 1621, 1584, 1549, 1462, 1209, 1046, 958, 746; H NMR (400
(trifluoromethylthio)phenoxy]phenyl}amine
Pharmaceutical Co. Ltd of Zhejiang province), HCOOH and selenium
1
powder to give: Oil; IR (KBr) (νmax cm−1): 2922, 2108, 1601, 1589, 1487,
MHz, DMSO-d6): δ 13.14 (s, 1H, NH), 8.22 (s, 1H, NH), 7.81–7.79 (m,
1H, ArH), 7.89 (s, 1H, N=CH), 7.10–7.01 (m, 2H, ArH), 6.73–6.70 (m,
1H, ArH), 2.23 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6): δ 158.4,
141.9, 141.6, 131.3, 128.5, 126.5, 123.7, 115.4, 17.6; MS (ESI) m/z (%):
175.1 ([M + H]+, 100%). HRMS (ESI) calcd for C9H11N4 [M + H]+:
175.0983; found: 175.0989.
3-[(3-Methylphenyl)amino]-2H-1,2,4-triazole (Table 2, 3c):
Light brown solid; yield 0.143 g (41%); m.p. 131–133 °C; IR (KBr)
(νmax cm−1): 3041, 2920, 1600, 1540, 1463, 1250, 1040, 979, 866, 778;
1H NMR (400 MHz, DMSO-d6): δ 13.20 (s, 1H, NH), 8.99 (s, 1H, NH),
8.25 (s, 1H, N=CH), 7.35–7.30 (m, 2H, ArH), 7.08–7.04 (m, 1H, ArH),
6.58 (s, 1H, ArH), 2.24 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6):
δ 160.1, 141.9, 141.7, 137.4, 128.3, 119.5, 115.9, 112.7, 21.5; MS (ESI)
m/z (%) 173.1 ([M − H]−, 100%). HRMS (ESI) calcd for C9H9N4 [M −
H]−: 173.0827; found: 173.0832.
1
1280, 1258, 1233, 1207, 1120, 1808, 1010, 854, 830, 751; H NMR
(400 MHz, DMSO-d6): δ 7.59 (d, J = 8.4 Hz, 2H, ArH), 7.22 (d, J = 2.4
Hz, 1H, ArH), 7.12 (dd, J1 = 1.2 Hz, J2 = 8.8 Hz, 1H, ArH), 6.91–6.88
(m, 3H, ArH), 2.22 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6): δ
153.5, 148.5, 138.2, 134.9, 132.8 (1JCF = 305 Hz), 131.6, 131.2, 121.8,
121.5, 117.8, 116.9, 116.3, 16.4; MS (ESI) m/z (%): 390 ([M + H]+, 100).
HRMS (ESI) calcd for C15H11F3NOS80Se (M + H)+: 389.9679; found:
389.9683.
Acknowledgements
We are grateful to the Natural Science Foundation of Jiangxi
Province (No. 20171BAB215075), Traditional Chinese
Medicine Research Key Project of Health and Family Planning
Commission of Jiangxi Province (No. 2017Z018) and National
Natural Science Foundation of China (No. 21576239) for
financial support.
3-[(4-Methylphenyl)amino]-2H-1,2,4-triazole (Table 2, 3d): Yellow
solid; yield 0.157 g (45%); m.p. 197–199 °C (lit.12 196–198 °C); IR

JOURNAL OF CHEMICAL RESEARCH 2018 259
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Electronic Supplementary Information
The ESI is available through:
http://ingentaconnect.com/content/stl/jcr/2018/00000042/00000005/art00007
Received 3 April 2018; accepted 9 May 2018
Paper 1805358
https://doi.org/10.3184/174751918X15260518865352
Published online: 30 May 2018
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