Copper-Catalyzed Decarboxylative Cycloaddition of Propiolic Acids, Azides, and Arylboronic Acids: Construction of Fully Substituted 1,2,3-Triazoles

Article abstract of DOI:10.1021/acs.joc.9b03285

A copper-catalyzed decarboxylative cycloaddition of propiolic acids, azides, and arylboronic acids is described. The present reaction provides an efficient and convenient method for the synthesis of various fully substituted 1,2,3-Triazoles from readily available starting materials. A possible mechanism is proposed.

Full text of DOI:10.1021/acs.joc.9b03285

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Article
Copper-Catalyzed Decarboxylative Cycloaddition of Propiolic Acids, Azides,
and Arylboronic Acids: Construction of Fully-Substituted 1,2,3-Triazoles
Xiang-Xiang Wang, Yangchun Xin, Yi Li, Wen-Jin Xia, Bin Zhou, Rui-Rong Ye, and Ya-Min Li
J. Org. Chem., Just Accepted Manuscript • Publication Date (Web): 27 Jan 2020
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Copper-Catalyzed Decarboxylative Cycloaddition of Propiolic Acids, Azides, and Arylboronic
Acids: Construction of Fully-Substituted 1,2,3-Triazoles
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Xiang-Xiang Wang,† Yangchun Xin,‡ Yi Li,† Wen-Jin Xia,† Bin Zhou,† Rui-Rong Ye,† and Ya-Min Li*†
†Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R.
China. E-mail: liym@kust.edu.cn.
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‡Katzin Diagnostic & Research PET/MR Center, Nemours/Alfred I. DuPont Hospital for Children, Wilmington,
DE 19803, United States.
Cu(OAc)2 (15 mol%)
DMBPy (30 mol%)
N
R2
N
N
R1
COOH
+
R2 N3 + R3B(OH)2
MeOLi (2.5 equiv)
CH3CN, 50 oC, O2
R1
R3
R1 = H, alkyl, aryl
R2 = alkyl
R3 = aryl
58 examples, up to 82% yield
good functional group tolerance
ABSTRACT: A copper-catalyzed decarboxylative cycloaddition of propiolic acids, azides, and arylboronic acids
is described. The present reaction provides an efficient and convenient method for the synthesis of various of
fully-substituted 1,2,3-triazoles from readily available starting materials. A possible mechanism is proposed.
INTRODUCTION
1,2,3-triazoles are an important class of N-heterocycles which widely exist in many biologically active molecules
and pharmaceuticals.1 It has been shown that 1,2,3-triazoles possess antibiotic, antiviral, antitumor, and
antiparasitic activities.2 They also serve as directing groups for C−H activations,3 ligands for homogeneous
catalysis,4 and building blocks in organic chemistry.5 Additionally, these N-heterocyclic compounds play an
indispensable role in materials science,6 polymer science,7 and biological conjugation.8 In view of their importance,
a vast array of methods were developed to synthesize 1,2,3-triazoles.9,10 Among the known synthetic methods, the
copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has attracted considerable attention because such
transformation is characterized by the mild reaction conditions, high yields, wide substrate scope, and exclusive
regioselectivity.10 However, the classical CuAAC reaction is limited to terminal alkynes, and provided only
1,4-disubstituted 1,2,3-triazoles because that copper(I) acetylide complexes which generated from terminal alkynes
and copper(I) salt is extremely significant for the reaction rate and near perfect regioselectivity. It is difficult to
construct fully-substituted 1,2,3-triazoles, especially bearing different groups at 4- and 5-positions, from internal
alkynes via CuAAC due to the high activation barrier and low regioselectivity.11 Thus, exploiting new strategies for
the construction of fully-substituted 1,2,3-triazoles has received increased attention.12,13 In this context, a few useful
methods have been developed to construct 5-arylsubstituted 1,2,3-triazoles.13 Ackermann and co-workers described
a copper-catalyzed one-pot multicomponent reaction of alkynes, azides, and aryl iodides through a CuAAC/direct
C-H arylation sequence to form 5-arylsubstituted 1,2,3-triazoles.13b A Cu/Pd transmetalation strategy was also
developed to achieve such triazoles from alkynes, azides, and aryl halides by Xu and co-workers.13g Recently, Song
group reported a Cu-catalyzed oxidative interrupted click reaction to construct 5-arylsubstituted triazoles using
arylboronic acids as aromatic sources.13h However, terminal alkynes of low molecular weight, such as acetylene
and propyne, were not suitable for the above-mentioned reactions due to their low boiling points. Therefore,
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developing an efficient method to construct a wide variety of 5-arylsubstituted 1,2,3-triazoles is still in need.
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As terminal alkyne surrogates, propiolic acids are more convenient to synthesize and utilize, and are generally
solids, even the most simple propiolic acid. The decarboxylative coupling of propiolic acids has thus attracted
considerable attention in recent years,14-16 and copper-catalyzed decarboxylative 1,3-dipolar cycloaddition of
propiolic acids have also been explored.17 Kolarovič and co-workers described a CuSO4·H2O-catalyzed
decarboxylative 1,3-dipolar cycloaddition of propiolic acids, sodium azide, and aryl iodides for the preparation of
1,4-disubstituted 1,2,3-triazoles under tandem catalysis conditions (Scheme 1a).17a Cu2O-catalyzed
decarboxylation/cycloaddition of propiolic acids and azides was also developed by our group (Scheme 1a).17b Pan
and Xu developed a Cu(OAc)2·H2O-catalyzed decarboxylation/cycloaddition cascade of propiolic acids,
diselenides and azides to access 5-arylselanyl-1,2,3-triazoles (Scheme 1b).17c However, synthesis of 5-arylated
1,2,3-triazoles via such decarboxylation/cycloaddition of propiolic acids remained underexplored. Based on our
continuous interest in decarboxylative coupling,17b,18 we demonstrate herein a copper-catalyzed decarboxylative
cycloaddition of propiolic acids, azides, and arylboronic acids to synthesize a wide variety of 5-arylated
1,2,3-triazoles (Scheme 1c).
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Scheme 1. Copper-Catalyzed Decarboxylative 1,3-Dipolar Cycloaddition
Previous work
N
R2
R2 N3
Cu2O
R2
I
N
N
NaN3,
R1
COOH
R1
COOH
(a)
(b)
CuSO4•H2O
K2CO3
R1
N
N
R2
Cu(OAc)2•H2O
N
N
R1
COOH
+
+
R3EER3
R2 N3
+
1,10-Phen
K2CO3
R1
ER3
E = Se, S
This work
R2
Cu(OAc)2
N
N
R1
COOH
R2 N3
+
ArB(OH)2
(c)
DMBPy
MeOLi
R1
Ar
RESULTS AND DISCUSSION
Initially, we chose phenylpropiolic acid (1a), benzyl azide (2a) and phenylboronic acid (3a) as the model
substrates to optimize the reaction conditions (Table 1). After a series of trials, it was found that when
phenylpropiolic acid 1a was treated with 1.5 equiv of benzyl azide and 2.5 equiv of phenylboronic acid in the
presence of 15 mol% Cu(OAc)2, 30 mol% 4,4'-dimethoxy-2,2'-bipyridine (DMBPy) and 2.5 equiv of MeOLi in
o
CH3CN at 50 C under an O2 atmosphere for 12 hours, the reaction afforded the triazole product 4a in 82% yield
(entry 1). Other copper salts such as CuCl, CuBr, and Cu(NO3)2·3H2O were less effective than Cu(OAc)2, and 20
mol% Cu(OAc)2 resulted in decreasing yield (entries 2-5). Notably, no reaction occurred in the absence of Cu
catalyst (entry 6). Different ligand, including 1,10-phen and 2,2'-bipyridine (BPy), were tested, the results indicate
DMBPy was the most efficient ligand for this reaction, and the appropriate amount of DMBPy was 30 mol%
(entries 7-9). Product 4a could be obtained in the absence of ligand, albeit with a lower yield (entry 10). Base is
crucial for the transformation, and this cascade could not take place without base (entry 11). When MeOLi was
replaced by t-BuOLi and t-BuONa, lower yields were obtained (entries 12 and 13). With AcOK as base, no product
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4a was detected (entry 14). Only trace amounts of 4a were detected when K2CO3 (1.5 equiv) or Na2CO3 (1.5 equiv)
was employed as base instead of MeOLi (entries 15 and 16). Other solvents including THF and i-PrOH were also
tested. CH3CN was proved to be the best choice (entries 17 and 18). Performing the reaction at a lower (40 oC) or
o
higher (60 C) temperature led to lower efficiency (entries 19 and 20). O2 atmosphere is also important for the
transformation, and it probably serves as an oxidant. When this reaction was performed under an air atmosphere,
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the product 4a was obtained only in 27% (entry 21).
Table 1. Optimization of the Reaction Conditionsa
Cu(OAc)2 (15 mol%)
DMBPy (30 mol%)
N
Bn
N
N
Ph
COOH
+
Bn N3 + PhB(OH)2
3a
MeOLi (2.5 equiv)
CH3CN, 50 oC, O2, 12 h
Ph
Ph
1a
2a
4a
Entry
1
Variation from the standard conditions
None
Yield (%)
82
2
CuCl instead of Cu(OAc)2
CuBr instead of Cu(OAc)2
Cu(NO3)2·3H2O instead of Cu(OAc)2
Cu(OAc)2 (20 mol%)
Without Cu(OAc)2
48
3
63
4
68
5
62
6
0
7
1,10-Phen instead of DMBPy
BPy instead of DMBPy
DMBPy (20 mol%)
46
8
25
9
63
10
11
12
13
14
15
16
17
18
19
20
21
Without DMBPy
38
Without MeOLi
0
t-BuOLi instead of MeOLi
t-BuONa instead of MeOLi
AcOK instead of MeOLi
K2CO3 (1.5 equiv) instead of MeOLi
Na2CO3 (1.5 equiv) instead of MeOLi
THF instead of CH3CN
i-PrOH instead of CH3CN
At 40 oC
62
14
0
Trace
Trace
23
18
64
At 60 oC
47
Under air
27
aReaction conditions: 1a (0.3 mmol), 2a (1.5 equiv), 3a (2.5 equiv), Cu(OAc)2 (15 mol%), DMBPy (30 mol%),
MeOLi (2.5 equiv), CH3CN (3 mL), O2 atmosphere, 50 oC, 12 h.
With the optimized reaction conditions in hand, the scope of propiolic acids was first examined. Various
propiolic acids, including aromatic and aliphatic propiolic acids were subjected to reaction with benzyl azide and
phenylboronic acid to afford the corresponding 5-arylsubstituted 1,2,3-triazoles (Table 2). Both electron-donating
(Me, OMe, SiMe3) and electron-withdrawing groups (CO2Me, NO2, COMe, CN) bearing phenylpropiolic acids
were compatible with this reaction, providing the triazoles 4a-4s in moderate to good yields. Halo functional
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groups, F, Cl and Br, were also well tolerated in this transformation, which provided scope for further
functionalization. Notably, ortho-substituted phenylpropiolic acids turned out to be compatible (4n-4s).
Naphthylpropiolic acid also proved to be suitable substrate, giving the triazole 4t in 59% yield. Heterocyclic
thienylpropiolic acid could yield the corresponding product 4u in 74% yield. Importantly, this decarboxylative
cycloaddition is not limited to arylpropiolic acids, alkylpropiolic acids including propiolic acid, but-2-ynoic acid,
pent-2-ynoic acid, hex-2-ynoic acid, oct-2-ynoic acid and 3-cyclopropylpropiolic acid also showed good efficiency,
leading to the triazoles in moderate yields (4v-4aa). 3-(Trimethylsilyl)propiolic acid is amenable to the present
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transformation as well, albeit in
a low yield (4ab). However, 4,4-dimethylpent-2-ynoic acid and
4-methoxybut-2-ynoic acid were inert under the standard conditions (4ac, 4ad).
Table 2. Scope of Propiolic Acidsa
Cu(OAc)2 (15 mol%)
DMBPy (40 mol%)
N
N
N
Ph
R
COOH + Ph
N3 + PhB(OH)2
MeOLi (2.5 equiv)
CH3CN, 50 oC, O2
Ph
2a
3a
1
4
N
N
N
N
N
N
Ph
Ph
4b
4f
, R = F, 68%
, R = Me, 65%
b
b
4c
4g
, R = OMe, 66%
, R = COCH3, 55%
Ph
Ph
4d
4e
4h
, R = Cl, 66%
, R = Br, 65%
, R = CN, 40%
c
4i
, R = SiMe3, 61%
4a
, 82%
R
4n
4o
4p
4q
N
N
, R = Me, 68%
, R = OMe, 60%
, R = Cl, 67%
, R = Br, 61%
, R = F, 64%
N
N
N
N
Ph
Ph
4j
, R = Me, 63%
R
4k
, R = Cl, 76%
Ph
Ph
4l
, R = F, 53%
R
4r
4m
, R = NO2, 71%
4s
, R = CO2CH3, 53%
N
N
N
N
N
N
N
S
N
Ph
Ph
N
N
N
N
Ph
Ph
Ph
Ph
Ph
Ph
4u
, 74%
4t
, 59%
4v
, 43%
4w
, 48%
N
N
N
N
N
N
N
N
N
N
N
N
Ph
Ph
Ph
Ph
Ph
Ph
Ph
, 50%
Ph
4x
, 48%
4y
4aa
, 41%
4z
, 52%
N
N
N
N
N
N
N
N
N
Ph
Ph
Ph
O
Me3Si
4ab
Ph
Ph
4ac
Ph
4ad
, 0%
, 38%
, 0%
aReaction conditions: 1 (0.3 mmol), 2a (1.5 equiv), 3a (2.5 equiv), Cu(OAc)2 (15 mol%), DMBPy (30 mol%) and
MeOLi (2.5 equiv) in CH3CN (3 mL) at 50 oC for 12 h under an O2 atmophere. bUsing 20 mol% Cu(OAc)2 and 40
mol% DMBPy. cAt 60 oC.
We next investigated the scope of boronic acids and organic azides (Table 3). For arylboronic acids, various
i
t
substituents, including Me, Et, Pr, Pr, Bu, F, Cl and Br, at the ortho-, meta- or para-position gave the 5-arylated
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triazoles in moderate to good yields (5a-5j). However, hydroxyl and cyano substituted phenylboronic acids were
not suitable substrates (5k and 5l). Multisubstituted phenylboronic acids were reacted well with phenylpropiolic
acid and benzyl azide, affording 5m-5o in considerable yields. Naphthylboronic acid and thiophen-2-ylboronic acid
were also amenable to the present transformation, albeit products 5p and 5q were obtained in low yields. However,
the alkylboronic acids such as methylboronic acid, phenethylboronic acid, and cyclohexylboronic acid were inert
under the standard conditions. With respect to azides employed, aside from benzyl azide, other aliphatic azides
such as (2-azidoethyl)benzene, 1-azidobutane and 1-azidohexane were also compatible with this reaction, giving
the corresponding products in moderate yields (6a-6c). Azidocyclopentane, a secondary azide, provided the product
6d in 47% yield. Hydroxyl, silanyl and ester substituted aliphatic azides also showed good efficiency (6e-6g). It is
noteworthy that aromatic azide such as azidobenzene failed to give the corresponding triazole 6h.
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Table 3. Scope of Boronic Acids and Azides a
Cu(OAc)2 (15 mol%)
DMBPy (30 mol%)
N
R1
N
N
+
+
R1 N3 R2
B(OH)2
Ph
COOH
MeOLi (2.5 equiv)
CH3CN, 50 oC, O2
Ph
R2
1a
2
3
5 6
,
5d
5e
5f
, R = Me, 57%
, R = n-Pr, 58%
, R = i-Pr, 55%
N
N
N
N
N
N
N
Ph
Ph
N
N
Ph
R
Ph
Ph
5g
, R = t-Bu, 64%
Ph
5h
, R = F, 73%
R
b
5i
5j
, R = Cl, 55%
, R = Br, 56%
5a
, R = Me, 72%
, R = Et, 44%
5c
, 75%
5k
5l
, R = OH, 0%
, R = CN, 0%
5b
N
N
N
N
N
N
Ph
N
N
N
N
N
N
Ph
F
Ph
Ph
Ph
Ph
Ph
Ph
c
5m
5n
, 61%
5o
5p
, 77%
, 68%
, 32%
N
N
N
N
N
N
N
N
N
Ph
Ph
N
N
N
Ph
Ph
Ph
Ph
Ph
5q
S
Ph
Ph
Me
5r
5s
, 0%
5t
, 20%
, 0%
, 0%
N
N
N
N
N
N
N
Ph
N
N
N
N
N
Ph
Ph
Ph
Ph
Ph
Ph
6c
Ph
Ph
c
, 61%
6a
6d
, 47%
, 39%
6b
, 33%
O
O
N
N
N
N
N
N
N
N
OH
SiMe3
N
N
N
N
Ph
Ph
Ph
Ph
Ph
Ph
6h
Ph
Ph
6g
c
6f
, 71%
6e
, 46%
, 73%
, 0%
aReaction conditions: 1 (0.3 mmol), 2a (1.5 equiv), 3a (2.5 equiv), Cu(OAc)2 (15 mol%), DMBPy (30 mol%) and
o
b
o
c
MeOLi (2.5 equiv) in CH3CN (3 mL) at 50 C for 12 h under an O2 atmosphere. At 60 C. Using 20 mol%
Cu(OAc)2 and 40 mol% DMBPy.
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In order to gain mechanistic insights into this decarboxylative cycloaddition, several control experiments were
carried out (Scheme 2). Initially, when 1,2-diphenylethyne 7 was treated with benzyl azide 2a under the standard
conditions, no triazole product 4a was detected, thus implying that the CuAAC of internal alkynes should not be
involved in this transformation (Scheme 2a). Furthermore, the reaction of 1,4-disubstituted 1,2,3-triazole 8 with
phenylboronic acid 3a was also performed under the standard conditions, no product 4a was formed. This result
illustrates that the disubstituted triazole is not a key intermediate in the process of decarboxylation/cycloaddition
cascade, and the mechanism involving C−H arylation should be ruled out (Scheme 2b). When alkynyl copper 9 was
used as the substrate instead of phenylpropiolic acid 1a, triazole 4a was obtained in 15% yield in the absence of
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o
Cu(OAc)2 (Scheme 2c). However, a moderate yield was achieved when such reaction was performed at 25 C
(Scheme 2d). Meanwhile, 4a was isolated in 72% yield when alkynyl copper 9 was employed as the catalyst
(Scheme 2e). These results suggest that alkynyl copper is likely to be involved in this reaction. Finally, when this
reaction was carried out under argon atmosphere, no 5-arylsubstituted triazole 4a was observed, while
1,4-disubstituted 1,2,3-triazole 8 was isolated in 90% yield, which implying that O2 is crucial for arylation.
Scheme 2. Mechanistic Studies
N
Bn
N
N
standard conditions
Ph
Ph
Bn
+
+
(a)
(b)
(c)
Bn N3
Ph
Ph
7
2a
4a
, 0%
N
N
Bn
N
N
N
N
standard conditions
PhB(OH)2
Ph
Ph
, 0%
Ph
3a
8
4a
DMBPy (30 mol%)
MeOLi (2.5 equiv)
N
Bn
Bn
N
Ph
N
Ph
Cu
Cu
+
Bn N3
+
+
PhB(OH)2
CH3CN, 50 oC, O2
Ph
2a
9
3a
4a
, 15%
DMBPy (30 mol%)
MeOLi (2.5 equiv)
N
N
N
(d)
(e)
(f)
Ph
+
Bn N3
PhB(OH)2
CH3CN, r.t., O2
Ph
4a
Ph
2a
9
3a
, 40%
9
(15 mol%)
DMBPy (30 mol%)
N
Bn
N
N
Ph
COOH + Bn N3 + PhB(OH)2
MeOLi (2.5 equiv)
CH3CN, 50 oC, O2
Ph
Ph
, 72%
1a
2a
3a
4a
Cu(OAc)2 (15 mol%)
DMBPy (30 mol%)
N
N
Bn
Bn
N
N
N
N
1a
2a
3a
+
+
+
MeOLi (2.5 equiv)
CH3CN, 50 oC, Ar
Ph
Ph
, 0%
Ph
4a
8
, 90%
Based on the literature and above experimental results, we proposed a possible mechanism for this
transformation (Scheme 3). Initially, the decarboxylation of propiolic acid generates the copper(I) acetylide A in
the presence of copper salt and MeOLi.19 Subsequently, the [3+2] cycloaddition of copper(I) acetylide with the
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azide leads to triazolyl-copper intermediate C, followed by a transmetalation with borate complex generated from
phenylboronic acid and MeOLi under oxidative conditions to afford the intermediate D.20 Finally, reductive
elimination of the intermediate D provides the triazole 4a and releases the copper (I) species. O2 probably acts as an
oxidant to produce high oxidation state copper intermediates.
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Scheme 3. Proposed Mechanism
Ph
CO2H
Cu(II)Ln, MeOLi
CO2
1a
MeOLi
Cu(I)Ln
N
Bn
N
N
Ph
Cu(I)Ln
CO2
A
Ph
Ph
Bn N3
4a
N
Bn
N
N
HN N
N Bn
Ph
Cu(III)Ln
Ph
D
Ph
Cu(I)Ln
O2
B
LiB(OMe)4-n(OH)n
MeOLi
N
Bn
N
N
PhB(OH)2
Ph
Cu(I)Ln
[PhB(OMe)3-n(OH)n] Li
N
Bn
N
N
C
Ph
8
CONCLUSIONS
In conclusion, we have successfully developed a copper-catalyzed decarboxylative cycloaddition of propiolic
acids, azides, and arylboronic acids for the preparation of fully-substituted 1,2,3-triazoles. This reaction featured
with wide substrate scope, mild reaction conditions, readily available starting materials, operational simplicity, and
using molecular oxygen as the oxidant. Further studies on application of this decarboxylative cycloaddition is
ongoing.
Experimental Section
General information. Commercial reagents were used directly as supplied. Column chromatography was
carried out on silica gel (200-300 mesh ASTM). Propiolic acids21 and (phenylethynyl)copper22 were prepared
according to the reported literatures. Melting points were measured on an X-4 digital melting-point apparatus.
NMR spectra were recorded on a Bruker AV 600 MHz spectrometer with tetramethylsilane (TMS) as an internal
standard. CDCl3 was used as the NMR solvent in all cases. High resolution mass spectra (HRMS) were recorded on
a Thermo LTQ Orbitrap XL spectrometer. IR spectra were measured on a Bruker Tensor 27 FT-IR spectrometer.
General Procedure for Copper-Catalyzed Decarboxylative Cycloaddition of Propiolic acids, Azides, and
Arylboronic Acids.
In a 20 mL Schlenk tube, propiolic acid 1 (0.3 mmol, 1.0 equiv), azide 2 (0.45 mmol, 1.5 equiv), arylboronic acid 3
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(0.75 mmol, 2.5 equiv), Cu(OAc)2 (8.2 mg, 0.045 mmol, 0.15 equiv), 4,4'-dimethoxy-2,2'-bipyridine (19.5 mg, 0.09
mmol, 0.3 equiv) and MeOLi (28.5 mg, 0.75 mmol, 2.5 equiv) were added and charged with O2 three times. Then
CH3CN (3 mL) were added, and the reaction mixture was stirred at 50 oC (oil bath temperature) for 12 hours. Upon
completion of the reaction, the mixture was diluted with ethyl acetate, and washed with H2O. After the organic
layer was dried over anhydrous MgSO4, filtered, and concentrated by rotary evaporation, the crude residue was
purified by silica gel column chromatography (eluting with petroleum ether/ethyl acetate) to give pure product 4.
General Procedure for Synthesis of 4e and 5i.
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In a 20 mL Schlenk tube, propiolic acid 1 (0.3 mmol, 1.0 equiv), azide 2 (0.45 mmol, 1.5 equiv), arylboronic acid 3
(0.75 mmol, 2.5 equiv), Cu(OAc)2 (8.2 mg, 0.045 mmol, 0.15 equiv), 4,4'-dimethoxy-2,2'-bipyridine (19.5 mg, 0.09
mmol, 0.3 equiv) and MeOLi (28.5 mg, 0.75 mmol, 2.5 equiv) were added and charged with O2 three times. Then
CH3CN (3 mL) were added, and the reaction mixture was stirred at 60 oC (oil bath temperature) for 12 hours. Upon
completion of the reaction, the mixture was diluted with ethyl acetate, and washed with H2O. After the organic
layer was dried over anhydrous MgSO4, filtered, and concentrated by rotary evaporation, the crude residue was
purified by silica gel column chromatography (eluting with petroleum ether/ethyl acetate) to give the desired
product.
General Procedure for Synthesis of 4c, 4g, 5m, 6a and 6f.
In a 20 mL Schlenk tube, propiolic acid 1 (0.3 mmol, 1.0 equiv), azide 2 (0.45 mmol, 1.5 equiv), arylboronic acid 3
(0.75 mmol, 2.5 equiv), Cu(OAc)2 (10.9 mg, 0.06 mmol, 0.20 equiv), 4,4'-dimethoxy-2,2'-bipyridine (25.9 mg, 0.12
mmol, 0.4 equiv) and MeOLi (28.5 mg, 0.75 mmol, 2.5 equiv) were added and charged with O2 three times. Then
CH3CN (3 mL) were added, and the reaction mixture was stirred at 50 oC (oil bath temperature) for 12 hours. Upon
completion of the reaction, the mixture was diluted with ethyl acetate, and washed with H2O. After the organic
layer was dried over anhydrous MgSO4, filtered, and concentrated by rotary evaporation, the crude residue was
purified by silica gel column chromatography (eluting with petroleum ether/ethyl acetate) to give the desired
product.
1-Benzyl-4,5-diphenyl-1H-1,2,3-triazole (4a). Performed according to the general procedure, and purified by
column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 77 mg (82%) of 4a. White solid, mp 112–
o
1
113 C. H NMR (600 MHz, CDCl3) δ 7.58–7.53 (m, 2H), 7.50–7.45 (m, 1H), 7.41 (dd, J = 10.3, 4.7 Hz, 2H),
7.28–7.21 (m, 6H), 7.17–7.12 (m, 2H), 7.03 (dd, J = 6.3, 3.0 Hz, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz,
CDCl3) δ 144.5, 135.3, 133.9, 130.9, 130.1, 129.7, 129.1, 128.7, 128.4, 128.1, 127.8, 127.7, 127.5, 126.7, 52.0. IR
(KBr) υmax: 3059, 2936, 1603, 1499, 1451, 1363, 1387, 1246, 1075, 984, 736, 694 cm-1. HRMS (ESI): m/z: [M +
H]+ calc. for C21H18N3, 312.1495; found, 312.1493.
1-Benzyl-5-phenyl-4-(p-tolyl)-1H-1,2,3-triazole (4b). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 63 mg (65%) of 4b. White solid,
mp 138–139 oC. 1H NMR (600 MHz, CDCl3) δ 7.49–7.37 (m, 5H), 7.27–7.22 (m, 3H), 7.15–7.11 (m, 2H), 7.06 (d,
J = 8.0 Hz, 2H), 7.02 (dd, J = 6.6, 2.9 Hz, 2H), 5.40 (s, 2H), 2.29 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ
144.6, 137.4, 135.4, 133.5, 130.1, 129.6, 129.10, 129.08, 128.6, 128.1, 128.0, 127.9, 127.4, 126.6, 52.0, 21.2. IR
(KBr) υmax: 3029, 2932, 1641, 1516, 1455, 1356, 1248, 984, 824, 729, 697 cm-1. HRMS (ESI): m/z: [M + H]+ calc.
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for C22H20N3, 326.1652; found, 326.1651.
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1-Benzyl-4-(4-methoxyphenyl)-5-phenyl-1H-1,2,3-triazole (4c). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 68 mg (66%) of
4c. Pale yellow solid, mp 124–125 oC. 1H NMR (600 MHz, CDCl3) δ 7.50–7.44 (m, 3H), 7.43–7.38 (m, 2H), 7.27–
7.23 (m, 3H), 7.14 (s, 1H), 7.13 (t, J = 1.6 Hz, 1H), 7.02 (dd, J = 6.6, 2.9 Hz, 2H), 6.81–6.76 (m, 2H), 5.40 (s, 2H),
3.76 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 159.1, 144.4, 135.4, 133.0, 130.1, 129.5, 129.1, 128.6, 128.1,
127.94, 127.91, 127.4, 123.5, 113.8, 55.1, 52.0. IR (KBr) υmax: 3001, 2927, 2839, 1612, 1517, 1453, 1358, 1246,
1176, 1028, 836, 738 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H20N3O, 342.1601; found, 342.1601.
1-Benzyl-4-(4-chlorophenyl)-5-phenyl-1H-1,2,3-triazole (4d). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 68 mg (66%) of 4d. White
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solid, mp 140–143 oC. H NMR (600 MHz, CDCl3) δ 7.51–7.46 (m, 3H), 7.43 (t, J = 7.5 Hz, 2H), 7.28–7.24 (m,
3H), 7.24–7.20 (m, 2H), 7.14–7.11 (m, 2H), 7.02 (dd, J = 6.4, 2.8 Hz, 2H), 5.40 (s, 2H). 13C{1H} NMR (151 MHz,
CDCl3) δ 143.5, 135.1, 134.0, 133.5, 129.9, 129.8, 129.4, 129.3, 128.7, 128.6, 128.2, 127.9, 127.5, 127.4, 52.1. IR
(KBr) υmax: 3069, 2922, 1603, 1553, 1500, 1468, 1350, 1235, 1089, 982, 839, 724 cm-1. HRMS (ESI): m/z: [M +
H]+ calc. for C21H17ClN3, 346.1106; found, 346.1105.
1-Benzyl-4-(4-bromophenyl)-5-phenyl-1H-1,2,3-triazole (4e). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 76 mg (65%) of 4e. White
solid, mp 158–160 oC. 1H NMR (600 MHz, CDCl3) δ 7.49 (t, J = 7.5 Hz, 1H), 7.46–7.39 (m, 4H), 7.37 (d, J = 8.6
Hz, 2H), 7.28–7.23 (m, 3H), 7.12 (d, J = 7.3 Hz, 2H), 7.05–6.99 (m, 2H), 5.40 (s, 2H). 13C{1H} NMR (151 MHz,
CDCl3) δ 143.5, 135.1, 134.0, 131.6, 129.91, 129.85, 129.81, 129.3, 128.7, 128.18, 128.15, 127.5, 127.4, 121.7,
52.1. IR (KBr) υmax: 3068, 3025, 2923, 1644, 1496, 1452, 1348, 1069, 981, 837, 729, 557 cm-1. HRMS (ESI): m/z:
[M + H]+ calc. for C21H17BrN3, 390.0600; found, 390.0598.
1-Benzyl-4-(4-fluorophenyl)-5-phenyl-1H-1,2,3-triazole (4f). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 67 mg (68%) of 4f. Pale
yellow solid, mp 112–115 oC. 1H NMR (600 MHz, CDCl3) δ 7.54–7.46 (m, 3H), 7.45–7.40(m, 2H), 7.28–7.23 (m,
3H), 7.16–7.11 (m, 2H), 7.02 (dd, J = 6.4, 3.0 Hz, 2H), 6.97–6.91 (m, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz,
CDCl3) δ 162.3 (d, JC-F = 247.1 Hz), 143.7, 135.2, 133.6, 130.0, 129.8, 129.2, 128.7, 128.4 (d, JC-F = 8.1 Hz),
128.2, 127.6, 127.5, 127.0 (d, JC-F = 3.2 Hz), 115.4 (d, JC-F = 21.6 Hz), 52.1. IR (KBr) υmax: 3060, 2935, 1604,
1513, 1484, 1360, 1157, 1095, 985, 841, 735 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17FN3,
330.1401; found, 330.1398.
1-(4-(1-Benzyl-5-phenyl-1H-1,2,3-triazol-4-yl)phenyl)ethan-1-one (4g). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 5/1) to afford 58 mg (55%) of
4g. Pale yellow solid, mp 150–153 oC. 1H NMR (600 MHz, CDCl3) δ 7.85 (d, J = 8.7 Hz, 2H), 7.65 (d, J = 8.7 Hz,
2H), 7.54–7.49 (m, 1H), 7.45 (t, J = 7.6 Hz, 2H), 7.28–7.24 (m, 3H), 7.17–7.13 (m, 2H), 7.03 (dd, J = 6.6, 2.8 Hz,
2H), 5.42 (s, 2H), 2.56 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 197.6, 143.4, 135.9, 135.5, 135.0, 134.9, 130.0,
129.9, 129.3, 128.7, 128.6, 128.2, 127.5, 127.3, 126.5, 52.1, 26.6. IR (KBr) υmax: 3063, 3002, 2924, 1681, 1604,
1454, 1357, 1268, 1023, 957, 739, 699cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C23H20N3O, 354.1601; found,
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4-(1-Benzyl-5-phenyl-1H-1,2,3-triazol-4-yl)benzonitrile (4h). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 5/1) to afford 40 mg (40%) of 4h. Pale
yellow solid, mp 132–134 oC. 1H NMR (600 MHz, CDCl3) δ 7.69–7.64 (m, 2H), 7.56–7.51 (m, 3H), 7.49–7.44 (m,
2H), 7.29–7.24 (m, 3H), 7.16–7.12 (m, 2H), 7.04–7.00 (m, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ
142.6, 135.4, 135.1, 134.8, 132.3, 130.2, 129.8, 129.5, 128.7, 128.3, 127.5, 127.0, 126.8, 118.8, 110.9, 52.1. IR
(KBr) υmax: 3066, 2921, 2221, 1610, 1509, 1353, 1245, 984, 869, 760, 701 cm-1. HRMS (ESI): m/z: [M + H]+ calc.
for C22H17N4, 337.1448; found, 337.1447.
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1-Benzyl-5-phenyl-4-(4-(trimethylsilyl)phenyl)-1H-1,2,3-triazole (4i). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 70 mg (61%) of
4i. Pale yellow solid, mp 128–130 oC. 1H NMR (600 MHz, CDCl3) δ 7.55 (d, J = 8.2 Hz, 2H), 7.50–7.46 (m, 1H),
7.44–7.39 (m, 4H), 7.27–7.23 (m, 3H), 7.16–7.13 (m, 2H), 7.02 (dd, J = 6.4, 3.0 Hz, 2H), 5.40 (s, 2H), 0.22 (s, 9H).
13C{1H} NMR (151 MHz, CDCl3) δ 144.4, 139.9, 135.3, 133.9, 133.4, 131.1, 130.1, 129.7, 129.1, 128.7, 128.1,
127.9, 127.5, 125.7, 52.0, -1.2. IR (KBr) υmax: 3060, 3031, 2953, 1603, 1452, 1348, 1248, 1103, 982, 842, 759, 700
cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C24H26N3Si, 384.1891; found, 384.1890.
1-Benzyl-5-phenyl-4-(m-tolyl)-1H-1,2,3-triazole (4j). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 61 mg (63%) of 4j. White solid,
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mp 47–49 oC. H NMR (600 MHz, CDCl3) δ 7.53 (s, 1H), 7.49–7.44 (m, 1H), 7.43–7.38 (m, 2H), 7.27–7.22 (m,
3H), 7.19 (d, J = 7.7 Hz, 1H), 7.16–7.12 (m, 2H), 7.10 (t, J = 7.6 Hz, 1H), 7.04 (d, J = 7.5 Hz, 1H), 7.02 (dd, J =
6.6, 2.9 Hz, 2H), 5.41 (s, 2H), 2.27 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.6, 138.1, 135.3, 133.8, 130.7,
130.0, 129.6, 129.1, 128.6, 128.4, 128.2, 128.1, 127.8, 127.5, 127.4, 123.7, 52.0, 21.4. IR (KBr) υmax: 3061, 3032,
2921, 1606, 1498, 1454, 1355, 1245, 858, 765, 700 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H20N3,
326.1652; found, 326.1649.
1-Benzyl-4-(3-chlorophenyl)-5-phenyl-1H-1,2,3-triazole (4k). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 79 mg (76%) of 4k. White
solid, mp 86–88 oC. 1H NMR (600 MHz, CDCl3) δ 7.63 (t, J = 1.8 Hz, 1H), 7.52–7.48 (m, 1H), 7.44 (t, J = 7.5 Hz,
2H), 7.35 (dt, J = 7.7, 1.3 Hz, 1H), 7.28–7.23 (m, 3H), 7.21–7.18 (m, 1H), 7.18–7.11 (m, 3H), 7.02 (dd, J = 6.6, 2.8
Hz, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 143.2, 135.1, 134.4, 134.3, 132.6, 129.9, 129.6, 129.3,
128.7, 128.2, 127.7, 127.5, 127.3, 126.7, 124.6, 52.1. IR (KBr) υmax: 3029, 2923, 1599, 1497, 1408, 1350, 1244,
1074, 892, 828, 762, 699 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17ClN3, 346.1106; found, 346.1106.
1-Benzyl-4-(3-fluorophenyl)-5-phenyl-1H-1,2,3-triazole (4l). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 52 mg (53%) of 4l. Pale
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yellow solid, mp 63–65 oC. H NMR (600 MHz, CDCl3) δ 7.52–7.48 (m, 1H), 7.46–7.41 (m, 2H), 7.33–7.30 (m,
1H), 7.29 (dd, J = 10.3, 1.7 Hz, 1H), 7.27–7.23 (m, 3H), 7.23–7.18 (m, 1H), 7.16–7.11 (m, 2H), 7.04–6.99 (m, 2H),
6.94–6.90 (m, 1H), 5.40 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 162.7 (d, JC-F = 244.9 Hz), 143.3 (d, JC-F
=
2.7 Hz), 135.1, 134.2, 133.0 (d, JC-F = 8.6 Hz), 130.0, 129.94, 129.92, 129.3, 128.7, 128.2, 127.5, 127.3, 122.2 (d,
JC-F = 2.8 Hz), 114.5 (d, JC-F = 21.2 Hz), 113.4 (d, JC-F = 23.2 Hz), 52.1. IR (KBr) υmax: 3063, 2923, 1618, 1587,
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1503, 1355, 1208, 1073, 875, 765, 704 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17FN3, 330.1401; found,
330.1401.
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1-Benzyl-4-(3-nitrophenyl)-5-phenyl-1H-1,2,3-triazole (4m). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 5/1) to afford 76 mg (71%) of 4m. White
solid, mp 95–97 oC. 1H NMR (600 MHz, CDCl3) δ 8.39 (t, J = 1.9 Hz, 1H), 8.09–8.05 (m, 1H), 7.93–7.89 (m, 1H),
7.57–7.53 (m, 1H), 7.50–7.46 (m, 2H), 7.43 (t, J = 8.0 Hz, 1H), 7.29–7.25 (m, 3H), 7.17 (s, 1H), 7.15 (t, J = 1.6 Hz,
1H), 7.04 (dd, J = 7.3, 2.2 Hz, 2H), 5.44 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 148.4, 142.4, 134.9, 134.8,
132.7, 132.2, 130.3, 129.8, 129.5, 129.4, 128.8, 128.3, 127.5, 126.8, 122.3, 121.3, 52.2. IR (KBr) υmax: 3084, 2923,
1620, 1526, 1454, 1350, 1075, 895, 809, 768, 724 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17N4O2,
357.1346; found, 357.1345.
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1-Benzyl-5-phenyl-4-(o-tolyl)-1H-1,2,3-triazole (4n). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 66 mg (68%) of 4n. White solid,
mp 70–73 oC; 1H NMR (600 MHz, CDCl3) δ 7.37–7.33 (m, 1H), 7.33–7.26 (m, 5H), 7.23–7.18 (m, 2H), 7.16 (d, J
= 7.1 Hz, 1H), 7.13–7.08 (m, 3H), 7.06 (s, 1H), 7.05 (t, J = 1.6 Hz, 1H), 5.54 (s, 2H), 2.12 (s, 3H); 13C{1H} NMR
(151 MHz, CDCl3) δ 145.4, 137.2, 135.6, 135.2, 130.7, 130.3, 130.2, 129.5, 129.2, 128.9, 128.8, 128.2, 128.1,
127.4, 127.2, 125.5, 52.1, 20.3; IR (KBr) υmax: 3033, 2923, 1641, 1496, 1453, 1364, 1247, 1022, 984, 763, 732, 698
cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H20N3, 326.1652; found, 326.1649.
1-Benzyl-4-(2-methoxyphenyl)-5-phenyl-1H-1,2,3-triazole (4o). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 61 mg (60%) of
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4o. White solid, mp 86–87 oC. H NMR (600 MHz, CDCl3) δ 7.62 (dd, J = 7.6, 1.7 Hz, 1H), 7.37–7.25 (m, 7H),
7.12–7.09 (m, 2H), 7.09–7.06 (m, 2H), 6.98 (td, J = 7.5, 1.0 Hz, 1H), 6.76 (d, J = 8.2 Hz, 1H), 5.51 (s, 2H), 3.25 (s,
3H).13C{1H} NMR (151 MHz, CDCl3) δ 156.2, 142.5, 135.64, 135.59, 131.3, 129.6, 129.0, 128.9, 128.73, 128.67,
128.4, 128.0, 127.4, 120.6, 120.1, 110.9, 54.4, 52.0. IR (KBr) υmax: 3031, 2957, 2834, 1604, 1582, 1463, 1347,
1249, 1023, 984, 755, 691 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H20N3O, 342.1601; found, 342.1598.
1-Benzyl-4-(2-chlorophenyl)-5-phenyl-1H-1,2,3-triazole (4p). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 70 mg (67%) of 4p. White
solid, mp 86–89 oC. 1H NMR (600 MHz, CDCl3) δ 7.46–7.42 (m, 1H), 7.38–7.23 (m, 9H), 7.13–7.09 (m, 2H), 7.08
(s, 1H), 7.07 (t, J = 1.6 Hz, 1H), 5.55 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 143.4, 136.0, 135.4, 133.8,
132.3, 130.1, 129.7, 129.32, 129.29, 128.8, 128.1, 127.24, 127.18, 126.6, 52.1. IR (KBr) υmax: 3066, 2922, 1604,
1498, 1429, 1341, 1229, 1055, 915, 771, 710 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17ClN3,
346.1106; found, 346.1106.
1-Benzyl-4-(2-bromophenyl)-5-phenyl-1H-1,2,3-triazole (4q). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 71 mg (61%) of 4q. White
solid, mp 82–84 oC. 1H NMR (600 MHz, CDCl3) δ 7.55 (d, J = 8.0 Hz, 1H), 7.40–7.34 (m, 2H), 7.33–7.26 (m, 6H),
7.21–7.17 (m, 1H), 7.13–7.06 (m, 4H), 5.56 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.9, 135.8, 135.5,
132.9, 132.5, 132.2, 130.0, 129.4, 129.3, 128.79, 128.77, 128.1, 127.16, 127.15, 127.0), 124.1, 52.1. IR (KBr) υmax
:
3063, 3029, 1599, 1554, 1423, 1345, 1234, 1021, 982, 765, 710, 559 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for
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C21H17BrN3, 390.0600; found, 390.0599.
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1-Benzyl-4-(2-fluorophenyl)-5-phenyl-1H-1,2,3-triazole (4r). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 63 mg (64%) of 4r. White
solid, mp 90–91 oC. 1H NMR (600 MHz, CDCl3) δ 7.62 (td, J = 7.5, 1.7 Hz, 1H), 7.43–7.39 (m, 1H), 7.38–7.33 (m,
2H), 7.30–7.25 (m, 4H), 7.15 (td, J = 7.6, 1.1 Hz, 1H), 7.12–7.09 (m, 2H), 7.08 (dd, J = 6.6, 2.9 Hz, 2H), 6.99–6.94
(m, 1H), 5.50 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 159.5 (d, JC-F = 250.5 Hz), 140.4 (d, JC-F = 1.8 Hz),
135.9, 135.3, 131.2 (d, JC-F = 3.2 Hz), 129.9 (d, JC-F = 8.1 Hz), 129.38, 129.37, 129.36, 128.7, 128.1, 127.5 (d, JC-F
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= 2.1 Hz), 127.4, 124.1 (d, JC-F = 3.6 Hz), 118.9 (d, JC-F = 14.5 Hz), 115.9 (d, JC-F = 21.7 Hz), 52.2. IR (KBr) υmax
:
3061, 3030, 2968, 1622, 1583, 1445, 1346, 1224, 1098, 985, 823, 768 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for
C21H17FN3, 330.1401; found, 330.1401.
Methyl 2-(1-benzyl-5-phenyl-1H-1,2,3-triazol-4-yl)benzoate (4s). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 5/1) to afford 59 mg (53%) of
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4s. White solid, mp 90–91 oC. H NMR (600 MHz, CDCl3) δ 7.80–7.76 (m, 1H), 7.44 (t, J = 7.5 Hz, 1H), 7.39–
7.34 (m, 3H), 7.33–7.27 (m, 5H), 7.11–7.08 (m, 2H), 7.07 (d, J = 8.1 Hz, 2H), 5.53 (s, 2H), 3.56 (d, J = 0.4 Hz,
3H).13C{1H} NMR (151 MHz, CDCl3) δ 167.9, 144.7, 135.7, 135.0, 131.5, 131.4, 131.3, 131.0, 130.0, 129.6,
129.3, 128.8, 128.7, 128.1, 128.0, 127.1, 126.9, 52.0. IR (KBr) υmax: 3065, 2923, 2851, 1730, 1500, 1458, 1348,
1289, 1234, 1089, 767, 709 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C23H20N3O2, 370.1550; found, 370.1550.
1-Benzyl-4-(naphthalen-1-yl)-5-phenyl-1H-1,2,3-triazole (4t). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 5/1) to afford 64 mg (59%) of 4t. White
solid, mp 93–94 oC. 1H NMR (600 MHz, CDCl3) δ 8.09 (d, J = 8.4 Hz, 1H), 7.85–7.78 (m, 2H), 7.47–7.39 (m, 2H),
7.36–7.28 (m, 6H), 7.26–7.22 (m, 2H), 7.16 (dd, J = 7.6, 1.7 Hz, 2H), 7.06 (s, 1H), 7.05 (t, J = 1.6 Hz, 1H), 5.59 (s,
2H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.6, 136.0, 135.5, 133.7, 132.0, 129.6, 129.2, 128.81, 128.79, 128.7,
128.5, 128.2, 128.1, 127.4, 127.2, 126.3, 126.0, 125.8, 125.0, 52.2. IR (KBr) υmax: 3051, 2924, 1592, 1493, 1453,
1352, 1247, 965, 834, 772, 734, 696 cm-1. HRMS (ESI): calc. for C25H19N3 [M+H]+, 362.1652; found, 362.1653.
HRMS (ESI): m/z: [M + H]+ calc. for C25H20N3, 362.1652; found, 362.1653.
1-Benzyl-5-phenyl-4-(thiophen-2-yl)-1H-1,2,3-triazole (4u). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 70 mg (74%) of 4u. Brown
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solid, mp 127–130 oC. H NMR (600 MHz, CDCl3) δ 7.53–7.48 (m, 1H), 7.47–7.41 (m, 2H), 7.28–7.22 (m, 3H),
7.20–7.16 (m, 3H), 7.04–6.98 (m, 3H), 6.92–6.88 (m, 1H), 5.39 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 140.6,
135.1, 133.1, 132.8, 130.2, 130.0, 129.1, 128.7, 128.2, 127.5, 127.2, 127.0, 124.9, 124.1, 52.1. IR (KBr) υmax: 3061,
3029, 2923, 1604, 1502, 1454, 1354, 1245, 1072, 983, 760, 694 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for
C19H16N3S, 318.1059; found, 318.1060.
1-Benzyl-5-phenyl-1H-1,2,3-triazole (4v). Performed according to the general procedure, and purified by
column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 30 mg (43%) of 4v. White solid, mp 62–63
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oC. H NMR (600 MHz, CDCl3) δ 7.74 (s, 1H), 7.47–7.38 (m, 3H), 7.31–7.23 (m, 5H), 7.08 (dd, J = 7.3, 2.0 Hz,
2H), 5.55 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 138.1, 135.4, 133.2, 129.5, 128.9, 128.82, 128.76, 128.1,
127.1, 126.8, 51.7. IR (KBr) υmax: 3119, 3061, 2957, 2924, 1603, 1453, 1360, 1247, 977, 850, 783, 736 cm-1.
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HRMS (ESI): m/z: [M + H]+ calc. for C15H14N3, 236.1182; found, 236.1181.
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1-Benzyl-4-methyl-5-phenyl-1H-1,2,3-triazole (4w). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 36 mg (48%) of 4w. White
solid, mp 63–64 oC. 1H NMR (600 MHz, CDCl3) δ 7.45–7.39 (m, 3H), 7.28–7.22 (m, 3H), 7.16–7.12 (m, 2H), 7.02
(dd, J = 6.5, 2.9 Hz, 2H), 5.43 (s, 2H), 2.30 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 141.5, 135.5, 134.5, 129.4,
129.2, 128.8, 128.6, 128.0, 127.3, 127.2, 52.0, 10.6. IR (KBr) υmax: 3032, 2955, 2923, 1605, 1494, 1453, 1361,
1212, 1135, 1015, 740, 698 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C16H16N3, 250.1339; found, 250.1339.
1-Benzyl-4-ethyl-5-phenyl-1H-1,2,3-triazole (4x). Performed according to the general procedure, and purified
by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 38 mg (48%) of 4x. White solid, mp 53–
54 oC. 1H NMR (600 MHz, CDCl3) δ 7.46–7.38 (m, 3H), 7.26–7.22 (m, 3H), 7.12 (dd, J = 7.7, 1.3 Hz, 2H), 7.04–
6.99 (m, 2H), 5.41 (s, 2H), 2.68–2.62 (m, 2H), 1.22 (t, J = 7.6 Hz, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 147.2,
135.6, 134.0, 129.6, 129.2, 128.8, 128.6, 128.0, 127.5, 127.3, 51.9, 18.5, 14.2. IR (KBr) υmax: 3059, 2930, 1653,
1559, 1507, 1478, 1368, 1249, 982, 864, 762, 698 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for C17H18N3, 264.1495;
found, 264.1495.
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1-Benzyl-5-phenyl-4-propyl-1H-1,2,3-triazole (4y). Performed according to the general procedure, and purified
by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 42 mg (50%) of 4y. White solid, mp 54–
55 oC. 1H NMR (600 MHz, CDCl3) δ 7.46–7.37 (m, 3H), 7.26–7.21 (m, 3H), 7.11 (dd, J = 7.9, 1.4 Hz, 2H), 7.03–
6.97 (m, 2H), 5.40 (s, 2H), 2.63–2.56 (m, 2H), 1.70–1.62 (m, 2H), 0.88 (t, J = 7.4 Hz, 3H). 13C{1H} NMR (151
MHz, CDCl3) δ 145.9, 135.6, 134.4, 129.7, 129.2, 128.8, 128.6, 127.9, 127.5, 127.3, 51.9, 27.0, 22.9, 13.8. IR
(KBr) υmax: 3062, 3031, 2958, 2870, 1495, 1455, 1316, 1222, 1012, 824, 764, 701 cm-1. HRMS (ESI): m/z: [M+H]+
calc. for C18H20N3, 278.1652; found, 278.1650.
1-Benzyl-4-pentyl-5-phenyl-1H-1,2,3-triazole (4z). Performed according to the general procedure, and purified
by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 48 mg (52%) of 4z. White solid, mp 57–
58 oC. 1H NMR (600 MHz, CDCl3) δ 7.45–7.38 (m, 3H), 7.26–7.21 (m, 3H), 7.11 (dd, J = 7.8, 1.4 Hz, 2H), 7.03–
6.97 (m, 2H), 5.40 (s, 2H), 2.64–2.57 (m, 2H), 1.68–1.59 (m, 2H), 1.28–1.21 (m, 4H), 0.82 (t, J = 7.0 Hz, 3H).
13C{1H} NMR (151 MHz, CDCl3) δ 146.1, 135.6, 134.3, 129.6, 129.2, 128.8, 128.6, 127.9, 127.5, 127.3, 51.9,
31.4, 29.3, 25.0, 22.3, 13.9. IR (KBr) υmax: 3063, 2929, 2857, 1606, 1495, 1455, 1314, 1215, 1013, 764, 701 cm-1.
HRMS (ESI): m/z: [M+H]+ calc. for C20H24N3 , 306.1965; found, 306.1966.
1-Benzyl-4-cyclopropyl-5-phenyl-1H-1,2,3-triazole (4aa). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 34 mg (41%) of 4aa. White
solid, mp 82–84 oC. 1H NMR (600 MHz, CDCl3) δ 7.46–7.39 (m, 3H), 7.26–7.24 (m, 3H), 7.24–7.20 (m, 2H), 7.02
(dd, J = 6.4, 2.6 Hz, 2H), 5.42 (s, 2H), 1.79–1.71 (m, 1H), 1.05–1.00 (m, 2H), 0.89–0.84 (m, 2H). 13C{1H} NMR
(151 MHz, CDCl3) δ 146.8, 135.7, 134.4, 129.7, 129.1, 128.8, 128.6, 129.0, 127.4, 127.3, 51.9, 7.6, 6.3. IR (KBr)
υmax: 3064, 2994, 1631, 1497, 1429, 1377, 1257, 1209, 1034, 772, 701 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for
C18H18N3, 276.1495; found, 276.1494.
1-Benzyl-5-phenyl-4-(trimethylsilyl)-1H-1,2,3-triazole (4ab). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 35 mg (38%) of 4ab. White
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solid, mp 53–55 oC. H NMR (600 MHz, CDCl3) δ 7.46–7.42 (m, 1H), 7.40–7.36 (m, 2H), 7.26–7.21 (m, 3H),
7.10–7.06 (m, 2H), 7.00 (dd, J = 6.6, 2.9 Hz, 2H), 5.37 (s, 2H), 0.13 (s, 9H). 13C{1H} NMR (151 MHz, CDCl3) δ
144.8, 143.5, 135.5, 129.9, 129.3, 128.50, 128.45, 128.4, 127.9, 127.5, 51.3, -1.0. IR (KBr) υmax: 3061, 3031, 2957,
2897, 1605, 1454, 1314, 1248, 1009, 843, 725 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C18H22N3Si, 308.1578,
found, 308.1577.
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1-Benzyl-4-phenyl-5-(o-tolyl)-1H-1,2,3-triazole (5a). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 70 mg (72%) of 5a. White solid,
mp 78–83 oC. 1H NMR (600 MHz, CDCl3) δ 7.58–7.49 (m, 2H), 7.42 (td, J = 7.6, 1.1 Hz, 1H), 7.29 (t, J = 7.5 Hz,
1H), 7.26–7.17 (m, 7H), 7.10 (d, J = 7.5 Hz, 1H), 6.94 (d, J = 7.1 Hz, 2H), 5.31 (dd, J = 57.7, 14.8 Hz, 2H), 1.61 (s,
3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.4, 138.4, 134.7, 132.8, 131.1, 130.7, 130.3, 130.1, 128.51, 128.49,
128.2, 128.0, 127.6, 127.3, 126.5, 125.6, 52.2, 19.1. IR (KBr) υmax: 3055, 3031, 2943, 1604, 1481, 1445, 1350,
1242, 981, 763, 696 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H20N3, 326.1652; found, 326.1649.
1-Benzyl-5-(2-ethylphenyl)-4-phenyl-1H-1,2,3-triazole (5b). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 45 mg (44%) of 5b. White
solid, mp 113–114 oC. 1H NMR (600 MHz, CDCl3) δ 7.57–7.52 (m, 2H), 7.47 (td, J = 7.7, 1.3 Hz, 1H), 7.33 – 7.27
(m, 2H), 7.25–7.18 (m, 6H), 7.05 (dd, J = 7.5, 1.1 Hz, 1H), 6.98–6.94 (m, 2H), 5.30 (q, J = 14.9 Hz, 2H), 2.05–1.97
(m, 1H), 1.95–1.87 (m, 1H), 0.74 (t, J = 7.6 Hz, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.5, 143.9, 134.7,
132.7, 131.0, 130.5, 130.3, 128.8, 128.5, 128.4, 128.2, 128.0, 127.6, 126.7, 126.4, 125.8, 52.1, 25.5, 13.9. IR (KBr)
υmax: 3061, 2967, 2934, 1604, 1502, 1454, 1354, 1245, 983, 760, 694 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for
C23H22N3, 340.1808; found, 340.1807.
1-Benzyl-4-phenyl-5-(m-tolyl)-1H-1,2,3-triazole (5c). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 73 mg (75%) of 5c. White solid,
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mp 107–109 oC. H NMR (600 MHz, CDCl3) δ 7.61–7.54 (m, 2H), 7.33–7.20 (m, 8H), 7.04 (dd, J = 6.5, 2.8 Hz,
2H), 6.95 (d, J = 7.3 Hz, 1H), 6.88 (s, 1H), 5.38 (s, 2H), 2.30 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.4,
138.9, 135.5, 134.1, 131.0, 130.7, 130.4, 129.0, 128.7, 128.4, 128.1, 127.7, 127.6, 127.6, 127.2, 126.6, 52.1, 21.3.
IR (KBr) υmax: 3048, 3030, 2921, 1604, 1496, 1445, 1351, 1245, 1072, 992, 736 cm-1. HRMS (ESI): m/z: [M + H]+
calc. for C22H20N3, 326.1652; found, 326.1649.
1-Benzyl-4-phenyl-5-(p-tolyl)-1H-1,2,3-triazole (5d). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 56 mg (57%) of 5d. White solid,
mp 128–130 oC. 1H NMR (600 MHz, CDCl3) δ 7.57 (d, J = 7.1 Hz, 2H), 7.29–7.19 (m, 8H), 7.08–7.00 (m, 4H),
5.39 (s, 2H), 2.42 (s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.4, 139.7, 135.5, 134.0, 131.0, 129.9, 129.8,
128.6, 128.4, 128.1, 127.6, 127.4, 126.6, 124.6, 51.8, 21.4. IR (KBr) υmax: 3065, 3030, 2917, 1607, 1515, 1484,
1454, 1363, 1314, 984, 828, 736 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H20N3, 326.1652; found, 326.1649.
1-Benzyl-4-phenyl-5-(4-propylphenyl)-1H-1,2,3-triazole (5e). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 62 mg (58%) of 5e. White
solid, mp 65–66 oC. 1H NMR (600 MHz, CDCl3) δ 7.59–7.54 (m, 2H), 7.27–7.19 (m, 8H), 7.06–7.00 (m, 4H), 5.40
(s, 2H), 2.67–2.62 (m, 2H), 1.73–1.65 (m, 2H), 0.97 (t, J = 7.3 Hz, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.4,
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144.3, 135.4, 134.0, 131.0, 129.8, 129.2, 128.6, 128.4, 128.0, 127.6, 127.5, 126.6, 124.8, 51.9, 37.8, 24.3, 13.7. IR
(KBr) υmax: 3065, 2958, 2924, 2855, 1603, 1444, 1362, 1019, 983, 847, 725, 694 cm-1. HRMS (ESI): m/z: [M + H]+
calc. for C24H24N3, 354.1965; found, 354.1966.
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1-Benzyl-5-(4-isopropylphenyl)-4-phenyl-1H-1,2,3-triazole (5f). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 58 mg (55%) of
5f. White solid, mp 96–99 oC. 1H NMR (600 MHz, CDCl3) δ 7.61–7.55 (m, 2H), 7.29–7.21 (m, 8H), 7.08–7.04 (m,
2H), 7.04–7.01 (m, 2H), 5.40 (s, 2H), 3.01–2.93 (m, 1H), 1.30 (d, J = 6.9 Hz, 6H). 13C{1H} NMR (151 MHz,
CDCl3) δ 150.5, 144.3, 135.4, 134.0, 131.0, 129.9, 128.6, 128.4, 128.0, 127.6, 127.5, 127.2, 126.7, 124.9, 51.9,
33.9, 23.8. IR (KBr) υmax: 3053, 2961, 2871, 1601, 1452, 1361, 1248, 983, 840, 730, 698 cm-1. HRMS (ESI): m/z:
[M + H]+ calc. for C24H24N3, 354.1965; found, 354.1964.
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1-Benzyl-5-(4-(tert-butyl)phenyl)-4-phenyl-1H-1,2,3-triazole (5g). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 71 mg (64%) of
5g. White solid, mp 147–148 oC. 1H NMR (600 MHz, CDCl3) δ 7.61–7.57 (m, 2H), 7.43–7.39 (m, 2H), 7.29–7.21
(m, 6H), 7.09–7.05 (m, 2H), 7.02 (dd, J = 6.4, 3.0 Hz, 2H), 5.40 (s, 2H), 1.36 (s, 9H). 13C{1H} NMR (151 MHz,
CDCl3) δ 152.8, 144.3, 135.5, 134.0, 131.0, 129.6, 128.6, 128.4, 128.0, 127.6, 127.5, 126.7, 126.0, 124.6, 51.9,
34.8, 31.2. IR (KBr) υmax: 3057, 2961, 2869, 1604, 1486, 1365, 1356, 1242, 985, 834, 735, 694 cm-1. HRMS (ESI):
m/z: [M + H]+ calc. for C25H26N3, 368.2121; found, 368.2119.
1-Benzyl-5-(4-fluorophenyl)-4-phenyl-1H-1,2,3-triazole (5h). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 72 mg (73%) of 5h. White
solid, mp 104–106 oC. 1H NMR (600 MHz, CDCl3) δ 7.53 (dt, J = 8.5, 2.2 Hz, 2H), 7.29–7.23 (m, 6H), 7.14–7.06
(m, 4H), 7.02 (dd, J = 6.6, 2.9 Hz, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 163.4 (d, JC-F = 250.6
Hz), 144.8, 135.2, 132.8, 132.1 (d, JC-F = 8.4 Hz), 130.7, 128.8, 128.5, 128.2, 127.8, 127.4, 126.7, 123.7 (d, JC-F
=
3.6 Hz), 116.4 (d, JC-F= 21.9 Hz), 52.1. IR (KBr) υmax: 3055, 2924, 1604, 1515, 1484, 1364, 1226, 1158, 986, 847,
739 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17FN3, 330.1401; found, 330.1401.
1-Benzyl-5-(4-chlorophenyl)-4-phenyl-1H-1,2,3-triazole (5i). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 57 mg (55%) of 5i. White
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solid, mp 121–122 oC. H NMR (600 MHz, CDCl3) δ 7.55–7.50 (m, 2H), 7.42–7.36 (m, 2H), 7.29–7.23 (m, 6H),
7.08–7.05 (m, 2H), 7.03 (dd, J = 6.5, 2.7 Hz, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.8, 135.9,
135.1, 132.6, 131.4, 130.5, 129.5, 128.8, 128.5, 128.3, 127.9, 127.3, 126.7, 126.2, 52.1. IR (KBr) υmax: 3065, 3030,
2923, 1601, 1497, 1474, 1363, 1242, 1090, 983, 843, 700 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17ClN3,
346.1106; found, 346.1104.
1-Benzyl-5-(4-bromophenyl)-4-phenyl-1H-1,2,3-triazole (5j). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 66 mg (56%) of 5j. White
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solid, mp 128–130 C. H NMR (600 MHz, CDCl3) δ 7.58–7.49 (m, 4H), 7.31–7.22 (m, 6H), 7.06–7.01 (m, 2H),
7.01–6.97 (m, 2H), 5.41 (s, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.8, 135.1, 132.6, 132.4, 131.6, 130.5,
128.8, 128.5, 128.3, 127.9, 127.3, 126.72, 126.70, 124.2, 52.1. IR (KBr) υmax: 3065, 2924, 1598, 1497, 1475, 1362,
1070, 1012, 983, 842, 736, 699, 564 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C21H17BrN3, 390.0600; found,
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1-Benzyl-5-(3,5-dimethylphenyl)-4-phenyl-1H-1,2,3-triazole (5m). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 78 mg (77%) of
5m. White solid, mp 141–143 oC. 1H NMR (600 MHz, CDCl3) δ 7.59 (dt, J = 8.4, 1.9 Hz, 2H), 7.30–7.20 (m, 6H),
7.09 (s, 1H), 7.05 (dd, J = 6.6, 3.0 Hz, 2H), 6.70 (s, 2H), 5.36 (s, 2H), 2.26 (s, 6H). 13C{1H} NMR (151 MHz,
CDCl3) δ 144.1, 138.7, 135.6, 134.2, 131.2, 131.0, 128.5, 128.4, 128.0, 127.7, 127.6, 127.53, 127.52, 126.5, 52.0,
21.2. IR (KBr) υmax: 3065, 2972, 1604, 1498, 1453, 1366, 1240, 1009, 855, 779, 724, 700 cm-1. HRMS (ESI): m/z:
[M + H]+ calc. for C23H22N3, 340.1808; found, 340.1805.
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1-Benzyl-5-(2,4-dimethylphenyl)-4-phenyl-1H-1,2,3-triazole (5n). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 62 mg (61%) of
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5n. White solid, mp 93–94 oC. H NMR (600 MHz, CDCl3) δ 7.55 (dd, J = 8.2, 1.3 Hz, 2H), 7.27–7.18 (m, 6H),
7.10 (d, J = 7.6 Hz, 1H), 7.06 (s, 1H), 6.97 (d, J = 7.8 Hz, 3H), 5.30 (dd, J = 38.9, 14.8 Hz, 2H), 2.41 (s, 3H), 1.59
(s, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.3, 140.0, 138.1, 134.8, 132.9, 131.5, 131.2, 130.1, 128.49, 128.45,
128.1, 128.0, 127.5, 127.2, 125.6, 124.2, 52.0, 21.4, 19.0. IR (KBr) υmax: 3069, 3032, 2945, 2920, 1607, 1443,
1355, 1244, 1028, 983, 826, 721, 696 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C23H22N3, 340.1808; found,
340.1809.
1-Benzyl-5-(4-fluoro-3-methylphenyl)-4-phenyl-1H-1,2,3-triazole (5o). Performed according to the general
procedure, and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 70 mg (68%) of
5o. White solid, mp 102–103 oC. 1H NMR (600 MHz, CDCl3) δ 7.57–7.53 (m, 2H), 7.30–7.22 (m, 6H), 7.07–7.01
(m, 3H), 6.95–6.91 (m, 1H), 6.87 (dd, J = 7.2, 1.5 Hz, 1H), 5.39 (s, 2H), 2.21 (d, J = 1.7 Hz, 3H). 13C{1H} NMR
(151 MHz, CDCl3) δ 161.9 (d, JC-F = 249.0 Hz), 144.6, 135.4, 133.3 (d, JC-F = 5.6 Hz), 133.1, 130.8, 129.3 (d, JC-F
= 8.4 Hz), 128.7, 128.5, 128.2, 127.7, 127.5, 126.6, 126.1 (d, JC-F = 17.9 Hz), 123.4 (d, JC-F = 3.9 Hz), 115.9 (d,
JC-F = 22.8 Hz), 52.1, 14.5 (d, JC-F = 3.4 Hz). IR (KBr) υmax: 3060, 2942, 1600, 1563, 1484, 1352, 1244, 1118, 824,
747, 693 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C22H19FN3, 344.1558; found, 344.1555.
1-Benzyl-5-(naphthalen-2-yl)-4-phenyl-1H-1,2,3-triazole (5p). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 35 mg (32%) of 5p. White
solid, mp 125–127 oC. 1H NMR (600 MHz, CDCl3) δ 7.91 (d, J = 8.1 Hz, 1H), 7.87 (d, J = 8.4 Hz, 1H), 7.73 (d, J =
8.1 Hz, 1H), 7.62 (s, 1H), 7.61–7.53 (m, 4H), 7.28–7.17 (m, 7H), 7.04 (d, J = 6.7 Hz, 2H), 5.44 (s, 2H). 13C{1H}
NMR (151 MHz, CDCl3) δ 144.6, 135.5, 133.8, 133.4, 133.0, 130.8, 129.9, 129.0, 128.7, 128.4, 128.19, 128.15,
127.9, 127.7, 127.5, 127.3, 126.88, 126.87, 126.7, 125.1, 52.1. IR (KBr) υmax: 3062, 2935, 1602, 1495, 1359, 1238,
991, 864, 827, 731, 699 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C25H20N3, 362.1652; found, 362.1650.
1-Benzyl-4-phenyl-5-(thiophen-2-yl)-1H-1,2,3-triazole (5q). Performed according to the general procedure,
and purified by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 19 mg (20%) of 5q. Brown
solid, mp 112–113 oC. 1H NMR (600 MHz, CDCl3) δ 7.62 (dd, J = 8.1, 1.4 Hz, 2H), 7.53 (dd, J = 5.1, 0.8 Hz, 1H),
7.33–7.24 (m, 6H), 7.13–7.10 (m, 1H), 7.08 (dd, J = 6.5, 2.7 Hz, 2H), 6.93 (dd, J = 3.5, 0.9 Hz, 1H), 5.48 (s, 2H).
13C{1H} NMR (151 MHz, CDCl3) δ 146.1, 135.2, 130.6, 130.5, 129.4, 128.7, 128.4, 128.2, 128.0, 127.9, 127.4,
127.1, 126.8, 126.6, 52.1. IR (KBr) υmax: 3103, 2933, 1637, 1484, 1455, 1355, 1243, 1011, 846, 730, 694 cm-1.
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HRMS (ESI): m/z: [M+H]+ calc. for C18H16N3S, 318.1059; found, 318.1060.
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1-Phenethyl-4,5-diphenyl-1H-1,2,3-triazole (6a). Performed according to the general procedure, and purified
by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 38 mg (39%) of 6a. White solid, mp 93–
o
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94 C. H NMR (600 MHz, CDCl3) δ 7.54–7.50 (m, 2H), 7.47 (t, J = 7.5 Hz, 1H), 7.41 (t, J = 7.6 Hz, 2H), 7.26–
7.19 (m, 6H), 6.98 (d, J = 7.2 Hz, 2H), 6.93 (dd, J = 6.4, 2.5 Hz, 2H), 4.38 (t, J = 7.4 Hz, 2H), 3.17 (t, J = 7.4 Hz,
2H). 13C{1H} NMR (151 MHz, CDCl3) δ 143.9, 137.2, 134.1, 130.9, 129.9, 129.5, 129.2, 128.8, 128.7, 128.4,
127.8, 127.6, 126.9, 126.6, 49.4, 36.6. IR (KBr) υmax: 3059, 2963, 1602, 1505, 1360, 1238, 1181, 1076, 980, 779,
697 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for C22H20N3, 326.1652; found, 326.1650.
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1-Butyl-4,5-diphenyl-1H-1,2,3-triazole (6b). Performed according to the general procedure, and purified by
column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 27 mg (33%) of 6b. White solid, mp 122–
o
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124 C. H NMR (600 MHz, CDCl3) δ 7.60–7.46 (m, 5H), 7.36–7.30 (m, 2H), 7.29–7.21 (m, 3H), 4.21 (t, J = 7.4
Hz, 2H), 1.81–1.73 (m, 2H), 1.31–1.23 (m, 2H), 0.84 (t, J = 7.4 Hz, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ
144.1, 133.6, 131.0, 129.9, 129.6, 129.3, 128.4, 128.2, 127.5, 126.7, 48.0, 32.1, 19.6, 13.4. IR (KBr) υmax: 3061,
2956, 2874, 1604, 1508, 1444, 1359, 1266, 1073, 983, 755, 700 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for
C18H20N3, 278.1652; found, 278.1652.
1-Hexyl-4,5-diphenyl-1H-1,2,3-triazole (6c). Performed according to the general procedure, and purified by
column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 56 mg (61%) of 6c. White solid, mp 82–84
oC.1H NMR (600 MHz, CDCl3) δ 7.58–7.48 (m, 5H), 7.33 (dd, J = 6.4, 3.0 Hz, 2H), 7.28–7.21 (m, 4H), 4.20 (t, J =
7.4 Hz, 2H), 1.81–1.74 (m, 2H), 1.27–1.15 (m, 6H), 0.83 (t, J = 7.0 Hz, 3H). 13C{1H} NMR (151 MHz, CDCl3) δ
144.1, 133.6, 131.0, 129.9, 129.6, 129.3, 128.4, 128.2, 127.5, 126.7, 48.2, 31.0, 30.0, 26.0, 22.3, 13.9. IR (KBr)
υmax: 3054, 2917, 2856, 1603, 1466, 1357, 1251, 1022, 981, 797, 698 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for
C20H24N3, 306.1965; found, 306.1964.
1-Cyclopentyl-4,5-diphenyl-1H-1,2,3-triazole (6d). Performed according to the general procedure, and purified
by column chromatography (petroleum ether/ethyl acetate = 7/1) to afford 41 mg (47%) of 6d. White solid, mp
o
132–134 C. 1H NMR (600 MHz, CDCl3) δ 7.57–7.49 (m, 5H), 7.36–7.31 (m, 2H), 7.26–7.20 (m, 3H), 4.56–4.48
(m, 1H), 2.31–2.21 (m, 2H), 2.10–1.97 (m, 4H), 1.70–1.60 (m, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ 144.0,
133.6, 131.2, 130.1, 129.5, 129.3, 128.6, 128.4, 127.5, 126.7, 59.3, 33.6, 24.7. IR (KBr) υmax: 3065, 2960, 2874,
1631, 1443, 1349, 1022, 983, 765, 696 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for C19H20N3, 290.1652; found,
290.1651.
2-(4,5-Diphenyl-1H-1,2,3-triazol-1-yl)ethan-1-ol (6e). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 1/1) to afford 37 mg (46%) of 6e. White solid,
mp 121–122 oC. 1H NMR (600 MHz, CDCl3) δ 7.47 – 7.43 (m, 1H), 7.42–7.38 (m, 2H), 7.38–7.35 (m, 2H), 7.24–
7.18 (m, 5H), 4.43 (t, J = 6.6 Hz, 1H), 4.26–4.22 (m, 2H), 4.20–4.16 (m, 2H). 13C{1H} NMR (151 MHz, CDCl3) δ
143.7, 134.7, 130.4, 130.3, 129.6, 129.1, 128.4, 127.7, 127.2, 126.8, 61.1, 50.6. IR (KBr) υmax: 3276, 3052, 2934,
2880, 1604, 1507, 1440, 1073, 987, 861, 781 cm-1. HRMS (ESI): m/z: [M + H]+ calc. for C16H16N3O,
266.1288; found, 266.1285.
4,5-Diphenyl-1-((trimethylsilyl)methyl)-1H-1,2,3-triazole (6f). Performed according to the general procedure,
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and purified by column chromatography (petroleum ether/ethyl acetate = 9/1) to afford 65 mg (71%) of 6f. White
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solid, mp 108–110 C. H NMR (600 MHz, CDCl3) δ 7.57–7.53 (m, 2H), 7.53–7.49 (m, 3H), 7.34–7.30 (m, 2H),
7.28–7.21 (m, 3H), 3.63 (s, 2H), 0.12 (s, 9H). 13C{1H} NMR (151 MHz, CDCl3) δ 143.6, 134.0, 131.2, 130.1,
129.5, 129.3, 128.6, 128.4, 127.4, 126.6, 39.4, -1.9. IR (KBr) υmax: 3060, 2930, 1653, 1559, 1507, 1478, 1368,
1249, 982, 864, 762, 698 cm-1. HRMS (ESI): m/z: [M+H]+ calc. for C18H22N3Si, 308.1578; found, 308.1577.
Ethyl 2-(4,5-diphenyl-1H-1,2,3-triazol-1-yl)acetate (6g). Performed according to the general procedure, and
purified by column chromatography (petroleum ether/ethyl acetate = 4/1) to afford 67 mg (73%) of 6g. White solid,
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mp 106–108 oC. H NMR (600 MHz, CDCl3) δ 7.60–7.55 (m, 2H), 7.54–7.47 (m, 3H), 7.35 (dd, J = 7.5, 1.2 Hz,
2H), 7.30–7.23 (m, 3H), 4.99 (s, 2H), 4.18 (q, J = 7.1 Hz, 2H), 1.22 (t, J = 7.1 Hz, 3H). 13C{1H} NMR (151 MHz,
CDCl3) δ 166.5, 144.3, 134.5, 130.6, 129.9, 129.8, 129.4, 128.4, 127.8, 127.3, 126.7, 62.2, 49.2, 14.0. IR (KBr)
υmax: 3070, 2989, 1750, 1605, 1508, 1446, 1367, 1211, 1021, 922, 780, 697 cm-1. HRMS (ESI): m/z: [M + H]+ calc.
for C18H18N3O2, 308.1394; found, 308.1392.
SUPPORTING INFORMATION
1H NMR and 13C NMR spectra of products.
ACKNOWLEDGMENT
We gratefully acknowledge financial support from the National Natural Science Foundation of China (Nos.
21662021 and 21871114), the Yunnan Fundamental Research Projects (No. 2017FB016), Ronald J Quinn AM
Academician Workstation (2019IC003) and Program for Innovative Research Team (in Science and Technology)
in Universities of Yunnan Province.
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