Synthesis of 1,4-disubstituted 1,2,3-triazoles by use of copper(I) and amino acids ionic liquid catalytic system

Article abstract of DOI:10.1055/s-0029-1217111

An efficient and green one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles from aryl iodides and alkyl chlorides, sodium azide, and terminal alkynes catalyzed by copper(I) and amino acid ionic liquid (AAIL) in [BMIM]BF⁴ was developed. The reactions proceeded smoothly to generate the corresponding products in high yields. In addition, CuI, AAIL, and [BMIM]BF⁴ could be recovered for six consecutive trials without significant loss of activity. Georg Thieme Verlag Stuttgart - New York.

Full text of DOI:10.1055/s-0029-1217111

PAPER
447
Synthesis of 1,4-Disubstituted 1,2,3-Triazoles by Use of Copper(I) and Amino
Acids Ionic Liquid Catalytic System
Synthesis
i
of 1,4-D
n
isubstituted
c
1,2,3-Tria
z
oles n Yan,a Lei Wang*a,b
a
Department of Chemistry, Huaibei Coal Teachers College, Huaibei, Anhui 235000, P. R. of China
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences,
Shanghai 200032, P. R. of China
b
Fax +86(561)3090518; E-mail: leiwang@hbcnc.edu.cn
Received 17 August 2009
previous work 1,4-disubstituted 1,2,3-triazoles were de-
rived from alkynes, sodium azide, and benzyl and alkyl
halides, but rarely from aryl halides.14
Abstract: An efficient and green one-pot synthesis of 1,4-disubsti-
tuted 1,2,3-triazoles from aryl iodides and alkyl chlorides, sodium
azide, and terminal alkynes catalyzed by copper(I) and amino acid
ionic liquid (AAIL) in [BMIM]BF4 was developed. The reactions
proceeded smoothly to generate the corresponding products in high
yields. In addition, CuI, AAIL, and [BMIM]BF4 could be recovered
for six consecutive trials without significant loss of activity.
As efficient catalysts, copper and its salts have been wide-
ly used in various of reactions such as Ullmann reaction,15
substitution,16 Diels–Alder reaction,17 asymmetric allylic
alkylation,18 1,3-dipolar cycloaddition,19 and so on. Most
recently, copper/amino acid systems have been widely
used in catalyzing cross-couplings, such as C–N bond,20a
C–O bond,20b C–S bond,20c C–C bond20d formation reac-
tions, under mild reaction conditions. In these reactions,
amino acids were found to be the efficient ligands.21 Ionic
liquids (ILs) have received more attention as eco-friendly,
reusable and alternative reaction media in organic synthe-
sis because of their unique properties.22 Much more atten-
tion has been focused on functionalized ionic liquids
(FILs), that is to say, through incorporation of additional
functional groups as a part of the cation and/or anion, the
so-called task-specific ionic liquids (TSILs) and their ap-
Key words: click reaction, triazoles, ionic liquids, amino acid, cop-
per
‘Click chemistry’, introduced by Sharpless and co-work-
ers,1 is a newer approach to the synthesis of drug-like mol-
ecules that can accelerate the drug discovery process by
utilizing a few practical and reliable reactions. The click
reaction has wide scope and is easy to perform, uses only
readily available reagents, and is insensitive to oxygen
and water. Nowadays this concept has found wide use in
drug discovery process and biochemistry.2
Of the reactions comprising click chemistry, the perfect plications in chemical research. Ohno and his co-worker
example is the Huisgen 1,3-dipolar cycloaddition of have developed amino acid ionic liquids and demonstrat-
alkynes to azides to form 1,4-disubsituted-1,2,3-triaz- ed their properties.23 When the amino acids served as an-
oles.3 The copper(I)-catalyzed reaction is mild and very ions in ionic liquids, they can also play an important role
efficient.4 The azide and alkyne functional groups are of N,O-ligand.
largely inert towards biological molecules and aqueous
Here we wish to disclose our results about an efficient and
environments, which allows the use of the Huisgen 1,3-di-
green one-pot synthesis of 1,4-disubstituted 1,2,3-triaz-
polar cycloaddition in target guided synthesis5 and activi-
oles from aryl iodides and alkyl chlorides, sodium azide,
ty-based protein profiling.6 The products of these
and terminal alkynes catalyzed by copper(I) and amino
reactions, 1,2,3-triazoles have similarities to the ubiqui-
acid ionic liquid (AAIL) in [BMIM]BF4 (Scheme 1). The
tous amide moiety found in nature, but unlike amides, is
reactions proceeded smoothly to generate the correspond-
not susceptible to cleavage. Additionally, they are nearly
ing products in high yields. It is important to note that CuI,
impossible to be oxidized or reduced. Thus, they have
AAIL, and [BMIM]BF4 could be recovered by general
been widely used as synthetic intermediates and in indus-
treatment of the reaction solution and reused for six con-
trial applications, such as dyes, anticorrosive agents, pho-
secutive trials without significant loss of activity.
tostabilizers, photographic materials, and agrochemicals.
For the click reaction, the catalysts might be copper(0)
R1
nanosize clusters,7 or appropriate copper(I) salts (CuI or
CuI (10 mol%), AAIL (20 mol%)
R1
R2
+ NaN
X
+
3
N
R2
CuBr) with triphenylphosphine,8 iminopyridine,9 or
mono-4 or polydentate10,11 nitrogen ligands. Our group
also developed this type of reaction with use of a silica-
supported copper(I) catalyst12 and in water under transi-
tion-metal-catalyst-free reaction conditions.13 In these
[BMIM]BF4, 60 °C
N
N
AAIL:
R1 = alkyl, aryl
R
R
2 = alkyl, X = Cl
2 = aryl, X = I, Br
N+
COO–
N
H
SYNTHESIS 2010, No. 3, pp 0447–0452
x
x
.
x
x
.2
0
0
9
Advanced online publication: 06.11.2009
DOI: 10.1055/s-0029-1217111; Art ID: F16709SS
© Georg Thieme Verlag Stuttgart · New York
Scheme 1 CuI and AAIL catalyzed ‘click reaction’

448
J. Yan, L. Wang
PAPER
The amino acid ionic liquids (AAILs) shown in Scheme 2 When the reaction was carried out in the presence of CuI
can be easily prepared by the following synthetic proce- without AAIL, less than 10% yield of the product was ob-
dure, also indicated in Scheme 2. The prepared served (Table 1, entry 12). Meanwhile, when the solvent
[BMIM]OH according to the literature24 or tetrabutylam- was changed from [BMIM]BF4 into Bu4NOAc or
monium hydroxide was reacted with appropriate amino [BMIM]OH, only 61% and 37% yield of product was ob-
acid such as L-proline, trans-4-hydroxy-L-proline, and tained, respectively (Table 1, entries 13 and 14).
N,N-dimethylglycine at room temperature, and the solu-
Table 1 Screening of the Copper Salt and AAILa
tion was then evaporated and dried in vacuo to generate
the desired amino acid ionic liquids (AAILs), A1, A2, A3,
B1, B2, and B3, respectively.
Ph
Cu catalyst, AAIL
+
+ PhI
H
NaN3
Ph
N
Ph
[BMIM]BF4, 60 °C
N
N
Entry
1
Copper salt
CuI
AAIL
A1
A2
A3
B1
B2
B3
A1
B1
A1
B1
B1
–
Yield (%)b
85
COO–
A1
N
N
N+
Me
Me
N
H
HO
2
CuI
49
N+
A2
A3
B1
COO–
N
3
CuI
57
H
4
CuI
88
Me
N+
N
COO–
N
Me
5
CuI
71
Me
6
CuI
56
N+
COO–
7
CuBr
CuBr
CuCl
CuCl
Cu(OAc)2
CuI
61
N
H
8
56
HO
N+
9
23
B2
B3
COO–
N
H
10
11
12
13
14
42
<10
<10
61c
37d
Me
N+
N
COO–
Me
CuI
B1
B1
N
N+
A1
Me
CuI
COOH
N
H
HO–
a Reaction conditions: phenylacetylene (102 mg, 1.00 mmol), PhI
(204 mg, 1.00 mmol), NaN3 (130 mg, 2.00 mmol), Cu salt (0.10
mmol) and AAIL (0.20 mmol) in [BMIM]BF4 (3.0 mL) at 60 °C for
10 h.
– H2O
N+
B1
b Isolated yield.
HO–
c Using Bu4NOAc (3.0 mL) instead of [BMIM]BF4 (3.0 mL).
d Using [BMIM]OH (3.0 mL) instead of [BMIM]BF4 (3.0 mL).
Scheme 2 Amino acid ionic liquids (AAILs) and their synthesis
After preparing the amino acid ionic liquids, a variety of
copper salts and prepared AAILs were screened. The 1,3-
dipolar cycloaddition reactions between phenylacetylene,
iodobenzene, and sodium azide was chosen as the model
reaction (Table 1). When the reaction of phenylacetylene,
iodobenzene, and sodium azide in a 1:1:2 molar ratio, was
catalyzed by CuI (10 mol%) and prepared AAIL (20
mol%) in [BMIM]BF4 at 60 °C for 10 hours, the corre-
sponding 1,4-disubstituted 1,2,3-triazole was obtained in
the range of 49–88% isolated yields (Table 1, entries 1–
6). Among prepared AAILs, tetrabutylammonium hy-
droxide with L-proline (B1) was found to be the most ef-
fective one (Table 1, entry 4). When CuI was changed into
CuBr or CuCl, a significant decrease in the product yield
was observed (Table 1, entries 7–10), and when Cu(II)
was used as catalyst instead of Cu(I), less than 10% yield
of the desired product was isolated (Table 1, entry 11).
Effects of other reaction conditions, such as solvent, time
and temperature on the reaction were investigated and the
results are shown in Table 2. Among the solvents tested,
[BMIM]BF4 was found to be the best one (Table 2, entry
3). Reaction time and temperature also affected the reac-
tion, and in our work, its yield remains 88% even if the re-
action time was prolonged to 24 hours (Table 2, entry 6).
When the reaction was performed in 6 hours, the yield of
product was decreased (Table 2, entry 5). Lowering the
temperature to 40 °C caused drastic decrease of the yield
(Table 2, entry 7) and raising the temperature to 80 °C
could not improve the product yield (Table 2, entry 8).
With respect to CuI and B1 loading, 10 mol% of CuI and
20 mol% of B1 were found to be optimal. When 5 mol%
of CuI and 10 mol% of B1 were used, the desired product
was isolated in 62% yield (Table 2, entry 9).
Synthesis 2010, No. 3, 447–452 © Thieme Stuttgart · New York

PAPER
Synthesis of 1,4-Disubstituted 1,2,3-Triazoles
449
Table 3 The Click Reaction Catalyzed by CuI and B1a
Table 2 Effect of Solvent, Time, and Temperature on the Click Re-
actiona
CuI (10 mol%)
B1 (20 mol%)
R1
Ph
+ R2
X
R1
H
N
R2
+
NaN3
CuI (10 mol%)
[BMIM]BF4, 60 °C
+
+
N
NaN3
PhI
Ph
H
N Ph
N
B1 (20 mol%)
N
N
Entry R1
R2
Bn
Bn
Ph
Ph
X
Cl
Cl
I
Yield (%)b
99c
97c
88
Entry
Solvent
EtOH
Time (h) Temp (°C) Yield (%)b
1
2
Ph
1
2
3
4
5
6
7
8
9
10
10
10
10
6
60
60
60
60
60
60
40
80
60
86
71
88
81
81
88
21
85
62c
n-C8H17
Ph
MeOH
3
[BMIM]BF4
[BMIM]PF6
[BMIM]BF4
[BMIM]BF4
[BMIM]BF4
[BMIM]BF4
[BMIM]BF4
4
n-C8H17
Ph
I
91
5
4-MeOC6H4
4-MeOC6H4
4-MeC6H4
4-MeC6H4
3-MeC6H4
3-MeC6H4
2-MeC6H4
2-MeC6H4
4-MeOC6H4
4-MeOC6H4
4-MeOC6H4
Ph
I
85
6
n-C8H17
Ph
I
87
24
10
10
10
7
I
91
8
n-C8H17
Ph
I
52
9
I
81
10
11
12
13
14
15
16
17
18
19
20
n-C8H17
Ph
I
67
a Reaction conditions: phenylacetylene (102 mg, 1.00 mmol), PhI
(204 mg, 1.00 mmol), NaN3 (130 mg, 2.00 mmol), CuI (19 mg, 0.10
mmol), and B1 (69 mg, 0.20 mmol) in [BMIM]BF4 (3.0 mL).
b Isolated yield.
I
79
n-C8H17
n-C6H13
I
63
c CuI (0.05 mmol) and B1 (0.10 mmol) were used in the reaction.
I
67
4-MeC6H4
4-MeC6H4
Ph
I
83
To examine the generality of the reaction, we extended
our studies to a variety of alkynes and organic halides.
When the reaction of phenylacetylene, alkyl chloride, and
sodium azide in a 1:1:2 molar ratio was catalyzed by CuI
(10 mol%) and B1 (20 mol%) in [BMIM]BF4 at 60 °C for
10 hours, the corresponding 1,4-disubstituted 1,2,3-triaz-
oles were obtained in almost quantitative yields (Table 3,
entries 1 and 2). When the alkyl chloride was changed to
aryl iodide, both aromatic and aliphatic alkynes gave
moderate to high yields of the corresponding products
(Table 3, entries 3–12). It is noteworthy that the position
of the substituted groups on the benzene rings affects the
reaction slightly (Table 3, entries 7–12). When other acet-
ylenes, such as oct-1-yne and 4-ethynyltoluene, were used
as alkyne partner, the reactions also underwent smoothly
and the corresponding products were obtained in good
yields (Table 3, entries 13–15). However, when aryl bro-
mides were used as one of the substrate, a drastic decrease
of the yields was observed (Table 3, entries 16–20).
I
68
Br
Br
Br
Br
Br
71d
61d
59d
23d
traced
Ph
4-NCC6H4
4-AcC6H4
4-AcC6H4
4-MeC6H4
Ph
n-C8H17
Ph
a Reaction conditions: alkyne (1.00 mmol), organic halide (1.00
mmol), NaN3 (130 mg, 2.00 mmol), CuI (19 mg, 0.10 mmol), and B1
(69 mg, 0.20 mmol) in [BMIM]BF4 (3.0 mL) at 60 °C for 10 h.
b Isolated yield.
c The reactions were performed at 50 °C for 6 h.
d The reactions were performed at 100 °C for 24 h.
repetitive cycles without significant loss of activity
(Table 4).
A possible mechanism of CuI- and AAIL-catalyzed click
reaction is shown in Scheme 3. The amino acid ionic liq-
uid (AAIL) played the role of ligand in the reaction. The
reaction is thought to proceed in a stepwise manner start-
ing with the coordination of Cu(I) with proline, and then
the generation of copper(I) acetylide 2. The concerted cy-
cloaddition was performed to generate 3, in which the 1,4-
isomer was favored because of the steric hindrance. Pro-
tonation of 3 gave the final 1,4-disubstituted 1,2,3-triaz-
oles 4.4a Further investigation is under way in our
laboratory.
To screen the recyclability of copper, amino acid ionic liq-
uid as the reaction medium, they were reused several
times under the standard reaction conditions. When the re-
action of phenylacetylene, iodobenzene, and sodium
azide in a 1:1:2 molar ratio, was catalyzed by CuI (10
mol%) and B1 (20 mol%) in [BMIM]BF4 at 60 °C for 10
hours, the corresponding 1,4-disubstituted 1,2,3-triazole
was obtained in 88% yield (Table 4, entry 1). After carry-
ing out the reaction and workup, recovered CuI, B1,
[BMIM]BF4, and fresh starting materials were charged
into the reaction system. The reactions still proceeded
well. CuI, B1, and [BMIM]BF4 could be recycled in six
In summary, an efficient and green one-pot synthesis of
1,4-disubstituted 1,2,3-triazoles from alkyl chlorides and
Synthesis 2010, No. 3, 447–452 © Thieme Stuttgart · New York

450
J. Yan, L. Wang
PAPER
Amino Acid Ionic Liquids (AAILs)
Table 4 Recyclability of the Catalytic System and Reaction Medi-
uma
A1–A3: To a 50 mL of round-bottomed flask was added 1-butyl-3-
methylimidazolium hydroxide ([BMIM]OH, 2.57 g, 16.5 mmol) in
H2O (10 mL) and L-proline (1.89 g, 16.5 mmol). After extracting
the mixture with MeOH (3 × 50 mL), the combined MeOH layers
were evaporated, and the residue was dried in vacuo to afford A1
(3.79 g, 91%). A2 and A3 were obtained following the above pro-
cedure.
reused
CuI (10 mol%)
B1 (20 mol%)
[BMIM]BF4
Ph
+
NaN3
+
PhI
Ph
H
N Ph
N
N
Run
1
Yield (%)b
Run
5
Yield (%)b
B1–B3: To a 50 mL of round-bottomed flask was added Bu4NOH
(10% in H2O, 2.45 g, 1.0 mmol) and L-proline (0.12 g, 1.0 mmol).
After the solid had dissolved, the pale yellow solution was extracted
with MeOH (3 × 10 mL), the combined MeOH layers were evapo-
rated, and the residue was dried in vacuo to give B1 (0.331 g, 93%).
B2 and B3 were prepared following the same procedure.
88
88
87
85
82
79
70
86c
2
6
3
7
4
8
Click Reaction; General Procedure
A two-necked round-bottomed flask containing a stirrer bar was
charged with terminal alkyne (1.00 mmol), NaN3 (130 mg, 2.00
mmol), organic halide (1.00 mmol), CuI (19 mg, 0.10 mmol), amino
acid ionic liquid B1 (69 mg, 0.20 mmol), and [BMIM]BF4 (3.0 mL)
under N2. The mixture was heated and stirred at 60 °C for 10 h. Af-
ter cooling to r.t., the mixture was extracted with Et2O (3 × 5 mL).
The combined organic layers were dried (MgSO4) and evaporated
under reduced pressure. The residue was purified by flash chroma-
tography (silica gel) to give the desired 1,4-disubstituted 1,2,3-tria-
zole (Table 3).
a Reaction conditions: phenylacetylene (102 mg, 1.00 mmol), PhI
(204 mg, 1.00 mmol), NaN3 (130 mg, 2.00 mmol), CuI (19 mg, 0.10
mmol), and B1 (69 mg, 0.20 mmol) were performed in [BMIM]BF4
(3.0 mL) at 60 °C for 10 h.
b Isolated yield.
c Additional CuI (0.10 mmol) was added.
CuI
O
O–
R1
H
N
Recyclability of the Catalyst System and Reaction Medium
After the reaction was carried out, the mixture (containing CuI, B1,
and [BMIM]BF4) was washed with Et2O (3 × 5 mL) and hexane
(3 × 5 mL). After drying the mixture in vacuo for 24 h, it could be
reused directly without further purification.
H
O
R1
– H+
O–
N
N
N
R2
H
+ H+
O
N
4
Cu
1-Benzyl-4-phenyl-1H-1,2,3-triazole25
O–
1
N
1H NMR (400 MHz, CDCl3): d = 5.50 (s, 2 H), 7.47–7.79 (m, 8 H),
7.62 (s, 1 H), 7.82 (d, J = 7.2 Hz, 2 H).
H
R1
Cu
2
O
13C NMR (100 MHz, CDCl3): d = 55.89, 120.11, 125.78, 127.49,
127.10, 130.07, 135.15, 146.60.
O–
N
H
1-Benzyl-4-octyl-1H-1,2,3-triazole26
R1
Cu
1H NMR (400 MHz, CDCl3): d = 0.88 (t, J = 6.0 Hz, 3 H), 1.25–
1.29 (m, 10 H), 1.62–1.68 (m, 2 H), 2.69 (t, J = 8.0 Hz, 2 H), 5.45
(s, 2 H), 7.12–7.42 (m, 6 H).
N
N
R2
N
R2
N+ N–
13C NMR (100 MHz, CDCl3): d = 15.02, 23.59, 26.68, 30.04, 32.66,
54.89, 121.60, 128.85, 129.12, 135.11, 149.23.
3
N
Scheme 3 Proposed mechanism of the reaction
1,4-Diphenyl-1H-1,2,3-triazole27
1H NMR (400 MHz, CDCl3): d = 7.36–7.39 (m, 1 H), 7.40–7.48 (m,
3 H), 7.47–7.58 (m, 2 H), 7.80 (d, J = 6.0 Hz, 2 H), 7.91 (d, J = 8.0
Hz, 2 H), 8.20 (s, 1 H).
13C NMR (100 MHz, CDCl3): d = 119.53, 120.02, 124.22, 127.50,
127.96, 128.06, 130.01, 131.09, 137.50, 148.96.
aryl iodides, sodium azide, and alkynes catalyzed by cop-
per(I) and amino acid ionic liquid B1 in [BMIM]BF4 has
been developed. The reactions proceeded smoothly to
generate the corresponding products in high yields. In ad-
dition, CuI, B1, and [BMIM]BF4 could be recovered for
six consecutive trials without significant loss of activity.
4-Octyl-1-phenyl-1H-1,2,3-triazole27
1H NMR (400 MHz, CDCl3): d = 0.88 (t, J = 6.0 Hz, 3 H), 1.25–
1.32 (m, 10 H), 1.37–1.40 (m, 2 H), 2.78–2.82 (t, J = 8.0 Hz, 2 H),
7.39–7.43 (m, 1 H), 7.49–7.53 (m, 2 H), 7.71–7.74 (m, 3 H).
1
All H NMR and 13C NMR spectra were recorded on a 400 MHz
13C NMR (100 MHz, CDCl3): d = 14.09, 22.65, 29.34, 31.85,
120.40, 128.39, 129.65, 149.21.
Bruker FT-NMR spectrometers. All chemical shifts are given in d
(ppm) with reference to TMS as an internal standard. The CHN
analysis was performed on a Vario El III elementary analyzer. Prod-
ucts were purified by flash chromatography on 230–400 mesh silica
gel. Chemicals and solvents were purchased from commercial sup-
pliers either from Aldrich, Fluka, USA, or Shanghai Chemical
Company, China and were used without purification prior to use.
1-(4-Methoxyphenyl)-4-phenyl-1H-1,2,3-triazole28
1H NMR (400 MHz, CDCl3): d = 3.88 (s, 3 H), 7.04 (d, J = 8.0 Hz,
2 H), 7.34–7.39 (m, 1 H), 7.44–7.48 (m, 2 H), 7.69 (d, J = 8.0 Hz,
2 H), 7.91 (d, J = 8.0 Hz, 2 H), 8.12 (s, 1 H).
Synthesis 2010, No. 3, 447–452 © Thieme Stuttgart · New York

PAPER
Synthesis of 1,4-Disubstituted 1,2,3-Triazoles
451
13C NMR (100 MHz, CDCl3): d = 55.63, 114.74, 122.16, 125.77,
128.31, 128.88, 130.30, 148.17, 159.79.
13C NMR (100 MHz, CDCl3): d = 22.96, 55.72, 114.50, 121.73,
125.77, 128.31, 128.88, 130.30, 138.47, 148.17, 159.79.
Anal. Calcd for C16H15N3O: C, 72.43; H, 5.70; N, 15.84. Found: C,
72.51; H, 5.84; N, 15.68.
1-(4-Methoxyphenyl)-4-octyl-1H-1,2,3-triazole28
1H NMR (400 MHz, CDCl3): d = 0.82 (t, J = 6.0 Hz, 3 H), 1.25–
1.32 (m, 10 H), 1.65–1.75 (m, 2 H), 2.77–2.81 (t, J = 8.0 Hz, 2 H),
3.87 (s, 3 H), 6.70–7.02 (m, 2 H), 7.60–7.63 (m, 3 H).
1-(4-Methoxyphenyl)-4-phenyl-1H-1,2,3-triazole
1H NMR (400 MHz, CDCl3): d = 3.85 (s, 3 H), 7.00 (d, J = 8.0 Hz,
2 H), 7.39–7.43 (m, 2 H), 7.59 (d, J = 8.0 Hz, 2 H), 7.70 (d, J = 8.0
Hz, 2 H), 8.11 (s, 1 H).
13C NMR (100 MHz, CDCl3): d = 14.10, 22.68, 29.30, 29.60, 30.92,
31.85, 33.20, 55.62, 114.32, 119.22, 120.80, 130.88, 145.66.
13C NMR (100 MHz, CDCl3): d = 55.61, 114.12, 123.24, 131.55,
4-Phenyl-1-p-tolyl-1H-1,2,3-triazole28
132.56, 148.12, 159.70.
1H NMR (400 MHz, CDCl3): d = 2.44 (s, 3 H), 7.32–7.38 (m, 4 H),
7.44–7.48 (m, 3 H), 7.66–7.68 (m, 2 H), 8.16 (s, 1 H).
Anal. Calcd for C15H12BrN3O: C, 54.56; H, 3.66; N, 12.73. Found:
C, 54.63; H, 3.79; N, 12.56.
13C NMR (100 MHz, CDCl3): d = 24.33, 117.61, 120.44, 125.82,
128.34, 128.89, 130.25, 138.89.
4-(4-Phenyl-1H-1,2,3-triazol-1-yl)benzonitrile30
1H NMR (400 MHz, CDCl3): d = 7.36 (d, J = 8.0 Hz, 2 H), 7.40–
7.45 (m, 3 H), 7.59–7.65 (m, 2 H), 7.70 (d, J = 8.0 Hz, 2 H), 8.10
(s, 1 H).
13C NMR (100 MHz, CDCl3): d = 113.12, 116.20, 127.20, 129.56,
132.30, 133.30, 148.25.
4-Octyl-1-p-tolyl-1H-1,2,3-triazole13
1H NMR (400 MHz, CDCl3): d = 0.89 (t, J = 6.0 Hz, 3 H), 1.25–
1.32 (m, 10 H), 1.36–1.39 (m, 2 H), 2.41 (s, 3 H), 2.77–2.80 (m, 2
H), 7.29–7.31 (m, 2 H), 7.58–7.60 (m, 2 H), 7.67 (s, 1 H).
13C NMR (100 MHz, CDCl3): d = 14.08, 22.64, 25.67, 29.20, 29.30,
31.84, 118.77, 120.31, 130.13, 138.44, 149.03.
1-[4-(4-Phenyl-1H-1,2,3-triazol-1-yl)phenyl]ethanone27
1H NMR (400 MHz, CDCl3): d = 2.78 (s, 3 H), 7.36 (d, J = 8.0 Hz,
2 H), 7.45–7.48 (m, 3 H), 7.52–7.55 (m, 2 H), 7.82–7.86 (m, 2 H),
8.15 (s, 1 H).
13C NMR (100 MHz, CDCl3): d = 29.65, 127.50, 129.83, 132.56,
133.80, 135.69, 148.20, 192.68.
4-Phenyl-1-m-tolyl-1H-1,2,3-triazole28
1H NMR (400 MHz, CDCl3): d = 2.46 (s, 3 H), 7.25–7.26 (m, 1 H),
7.42–7.48 (m, 4 H), 7.55–7.62 (m, 2 H), 7.90–7.92 (m, 2 H), 8.18
(s, 1 H).
13C NMR (100 MHz, CDCl3): d = 21.40, 117.57, 117.64, 121.18,
125.82, 128.36, 128.88, 129.52, 130.28, 136.99, 140.00, 148.27.
1-[4-(4-Octyl-1H-1,2,3-triazol-1-yl)phenyl]ethanone
1H NMR (400 MHz, CDCl3): d = 0.86 (t, J = 6.0 Hz, 3 H), 1.29–
1.35 (m, 10 H), 1.64–1.69 (m, 2 H), 2.72–2.80 (t, J = 8.0 Hz, 2 H),
2.87 (s, 3 H), 7.10–7.12 (m, 2 H), 7.60–7.63 (m, 2 H), 7.95 (s, 1 H).
4-Octyl-1-m-tolyl-1H-1,2,3-triazole13
1H NMR (400 MHz, CDCl3): d = 0.88 (t, J = 6.0 Hz, 3 H), 1.28–
1.30 (m, 10 H), 1.69–1.77 (m, 2 H), 2.44 (s, 3 H), 2.77–2.81 (m, 2
H), 7.21–7.40 (m, 2 H), 7.48–7.50 (m, 2 H), 7.57 (s, 1 H), 7.70 (s, 1
H).
13C NMR (100 MHz, CDCl3): d = 14.15, 22.78, 29.33, 29.65, 30.92,
31.85, 33.00, 118.57, 128.50, 146.81, 192.66.
13C NMR (100 MHz, CDCl3): d = 14.08, 22.64, 25.67, 29.20, 29.33,
31.84, 117.44, 121.09, 129.14, 129.41, 139.85, 149.08.
Anal. Calcd for C24H29N3O: C, 76.76; H, 7.78; N, 11.19. Found: C,
76.89; H, 7.90; N, 11.02.
4-Phenyl-1-o-tolyl-1H-1,2,3-triazole29
Acknowledgment
1H NMR (400 MHz, CDCl3): d = 2.40 (s, 3 H), 7.31–7.33 (m, 4 H),
7.48–7.52 (m, 3 H), 7.57–7.60 (m, 2 H), 8.10 (s, 1 H).
We are grateful for the financial support from the National Science
Foundation of China (No. 20772043), the National Science Found-
ation of Anhui Education Department (No. ZD2007005–1), and the
Foundation of Anhui Excellent Talents in University
(2009SQRZ091ZD).
13C NMR (100 MHz, CDCl3): d = 21.52, 120.12, 125.89, 129.36,
130.88, 133.98, 148.56.
4-Octyl-1-o-tolyl-1H-1,2,3-triazole
1H NMR (400 MHz, CDCl3): d = 0.88 (t, J = 6.0 Hz, 3 H), 1.27–
1.34 (m, 10 H), 1.33–1.36 (m, 2 H), 2.36 (s, 3 H), 2.75–2.79 (m, 2
H), 7.31–7.35 (m, 2 H), 7.52–7.57 (m, 2 H), 7.70 (s, 1 H).
References
13C NMR (100 MHz, CDCl3): d = 14.12, 20.20, 22.36, 29.23, 29.33,
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