Polymer-supported azide and copper(I): Green reusable reagent and catalyst for click cyclization

Article abstract of DOI:10.1080/00397911.2012.671434

In this work, polymer-supported copper(I) iodide catalyst and macroporous polymer-supported azide reagent were used to simplify the synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from α-bromo ketones/amides/esters following green chemistry principles.

Full text of DOI:10.1080/00397911.2012.671434

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Polymer-Supported Azide and Copper(I):
Green Reusable Reagent and Catalyst for
Click Cyclization
Jalal Albadi a & Mosadegh Keshavarz a
a Department of Chemistry, Gachsaran Branch, Islamic Azad
University, Gachsaran, Iran
Accepted author version posted online: 27 Dec 2012.Published
online: 28 Apr 2013.
To cite this article: Jalal Albadi & Mosadegh Keshavarz (2013): Polymer-Supported Azide and
Copper(I): Green Reusable Reagent and Catalyst for Click Cyclization, Synthetic Communications: An
International Journal for Rapid Communication of Synthetic Organic Chemistry, 43:15, 2019-2030
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Synthetic Communications1, 43: 2019–2030, 2013
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397911.2012.671434
POLYMER-SUPPORTED AZIDE AND COPPER(I): GREEN
REUSABLE REAGENT AND CATALYST FOR CLICK
CYCLIZATION
Jalal Albadi and Mosadegh Keshavarz
Department of Chemistry, Gachsaran Branch, Islamic Azad University,
Gachsaran, Iran
GRAPHICAL ABSTRACT
Abstract In this work, polymer-supported copper(I) iodide catalyst and macroporous
polymer-supported azide reagent were used to simplify the synthesis of 1,4-disubstituted-
1H-1,2,3-triazoles from a-bromo ketones/amides/esters following green chemistry
principles. This new one-pot protocol facilitates the workup of the reaction and provides
the products in short times and excellent yields. Heterogeneous catalyst and reagent can
be reused at least for five runs without significant yield decreases.
Keywords Alkynes; a-bromo ketones; 1,3-dipolar cycloaddition; green chemistry;
heterogeneous catalysis
INTRODUCTION
According to one of the basic principles of green chemistry, catalytic or
recyclable reagents are superior to stoichiometric reagents.[1] Polymer-supported
reagents are increasingly being used in the synthesis and purification of many organic
reactions.[2,3] They possess advantages such as reaction monitoring as well as
increased safety, more than ever when the unsupported reagents are toxic or danger-
ous, as they can be easily removed from reaction media and recycled.[4,5] In addition,
employing an excess amount of reagent is permissible without the need for additional
purification.
Sodium azide is an essential reagent, and copper(I) is a wonderful catalyst for
1,3-dipolar cycloaddition between organic azides and terminal alkynes, which is best
known as the click reaction.[6–8] This cycloaddition has been applied in various ways
Received August 28, 2011.
Address correspondence to Mosadegh Keshavarz, Department of Chemistry, Islamic Azad
University, Gachsaran Branch, Gachsaran, Iran. E-mail: chemistmosadegh@gmail.com
2019

2020
J. ALBADI AND M. KESHAVARZ
in drug discovery, chemical biology, and medicinal chemistry,[9–12] as well as material
science and solid-phase organic synthesis.[13–16] However, sodium azide and copper
salts are highly toxic compounds. Sodium azide is a potent toxin, has a similar tox-
icity as the cyanide ion (LD50 ¼ 27 mg=kg for rats), and can be absorbed through the
skin mucous membranes. Regardless of toxicity, copper(I) iodide salt suffers from
thermodynamic instability and the formation of undesired alkyne-alkyne coupling
products, which are sometimes observed in its presence.[17,18] On the other hand,
these homogeneous processes possess one or more disadvantages such as difficulty
separating the product from the reaction medium. These homogenous catalysts
are generally unrecyclable and have poor regioselectivity and long reaction times.
Nevertheless, nitrogen- or phosphorus-based ligands have been shown to
protect the metal center from oxidation and disproportionation while enhancing
its catalytic activity.[19–21] Recently, heterogeneous copper(I) catalysts based on
silica,[22–24] montmorillonite,[25] zeolites,[26–28] and Cu on charcoal[29,30] have been
developed. There are also some reports about using of polymer-supported CuI as
recoverable catalyst for this cyclization.[31–33] These catalysts possess increased
advantages over their homogeneous counterparts. However, to the best of our
knowledge, there is no report for one-pot multicomponent synthesis of 1,4-disubsti-
tuted 1,2,3-triazoles that utilize polymer-supported azide, which can significantly
reduce the toxicity and environmental impacts of this reagent.
In contination of our recent work that reported directly prepared phenacyl
azides from styrenes for click synthesis of 1,4-disubstituted triazole,[34] herein we
report a new, facile, and green protocol for one-pot multicomponent click synthesis
of 1,4-disubstituted-1H-1,2,3-triazoles from a-bromo ketones, amides, and esters
using polymer-supported azide and CuI.
RESULTS AND DISCUSSION
The preparation procedures followed to obtain polymer-supported Cu(I) iod-
ide catalyst and polymer-supported azide reagent are outlined in Schemes 1 and 2.
These consist of building up suitable heterogeneous polymer-supported copper(I)
iodide catalyst (Scheme 1) and macroporous polymer-supported azide nucleophile
(Scheme 2) structures on the surface of commercially available amberlyst A-21 (mesh
20–50) and amberlite IRA-910Cl (mesh 16–50). Preparation of heterogeneous
copper(I) iodide catalyst and polymer-supported azide reagent by these procedures
is facile and straightforward.
To optimize the reaction conditions, phenyl acetylene and phenacyl bromide
for the synthesis of 1-phenyl-2-(4-phenyl-1-H-1,2,3-triazol-1yl)-1-ethanone (Table 1,
entry 1b) were selected as the test substrates, and acetonitrile, methylene chloride,
ethanol, and water were selected as solvents. Unfortunately we did not get any result
Scheme 1. Preparation of amberlyst-supported CuI (A-21CuI). (Figure is provided in color online.)

REUSABLE CATALYST FOR CLICK CYCLIZATION
2021
Scheme 2. Preparation of amberlite-supported azide (IRA-910N3). (Figure is provided in color online.)
at room temperature with various amounts of heterogeneous catalyst and reagent
with each of the solvents, so the reaction was done at reflux conditions.
From Table 2, it can be seen that acetonitrile, A-21CuI (60 mg, 10%), and
IRA-910N3 (1 g) are optimized conditions for multicomponent click cyclization.
The results were evaluated qualitatively through thin-layer chromatography (TLC)
(Table 1). The best conditions employ 1:1:1.5:0.1 mol ratios of phenyl acetylene,
phenacyl bromide, IRA-910N3, and A-21CuI at reflux conditions using acetonitrile
as solvent.
Using these optimized conditions, the reaction of various terminal alkynes and
a-bromo ketones, amides, or esters was explored (Scheme 3). All the products were
easily isolated with straightforward filtration and evaporation of solvent. A simple
purification technique is one of the key characteristics of click reactions.[7] The solid
products were easily recrystallized in hot ethanol. In some cases, the solid product
was dissolved in a minimum amount of ethyl acetate and n-hexane was added drop-
wise to give pure product crystals (Table 1, entries 2, 13, and 14).
Click condensations were confirmed by the appearance of a singlet in the
1
region of 8–8.5 ppm in H NMR spectra, which corresponds to the hydrogen on
the 5-position of triazole ring and confirms the regioselective synthesis of 1,4-
disubstituted triazole regioisomers.[34] Because a-azido ketones are often unstable
in heat and light, their in situ preparation is a great alternative to their use and hand-
ling. a-Azido ketones were prepared in situ and subjected to multicomponent click
cyclization with various terminal alkynes.
The using of 1,3-diethynylbenzene in click cyclizations led to the synthesis
of some interesting symmetrical bis-triazoles (Table 1, entries 13 and 14 and
Scheme 4). a-Bromo amides and a-bromo esters were also subjected to click
cyclization with terminal alkynes to give the corresponding 1,4-disubstituted-1H-
1,2,3-triazloes in good yields (Table 1, entries 5 and 10 and Scheme 5).
It is also noteworthy that resins do not suffer from extensive mechanical degra-
dation after running. When using a heterogeneous catalyst, the key point is the
deactivation and recyclability of the catalyst. Polymer-supported CuI can be reused
for up to five runs without reloading. Polymer-supported azide nucleophile can be
loaded several times. To exhibit the reusability of the polymer-supported azide
and CuI, click cyclization of phenyl acetylene and phenacyl bromide was chosen
as a model. After reaction completion, the resin mixture was washed with distilled
water and then subjected to aqueous NaN3 solution to reload IRA-910N3. This pro-
cess was repeated five times and no appreciable yield decrease was observed (Table 3
and Fig. 1). The copper content of the amberlyst–CuI catalyst was measured with
atomic absorption spectroscopy after five runs (copper content was calculated to
be 1.25 mmol per gram of polymeric catalyst). The difference between the copper
content of the fresh catalyst and the used catalyst (fifth run) is only 5%, which indi-
cates the low leaching amount of copper iodide catalyst into the reaction mixture.

2022

2023

2024
J. ALBADI AND M. KESHAVARZ
Table 2. effect of solvent on the polymer-supported CuI=N3-mediated 1,4-disubstituted-1H-1,2,3-triazole
synthesis
Entry
Solvent
IRA-910N3 (g)
A-21CuI (mg)
Time (h)
Yield (%)a
1
2
3
4
CH3OH
H2O
1
1
1
1
60
60
60
60
2
2
2
1
45
40
65
89
CH2Cl2
CH3CN
aYields refer to pure and separated products.
To evaluate the catalytic property and reusability of other polymer-supported
Cu(I) salts, amberlyst-supported CuCl and CuBr were prepared according to the
procedure applied for CuI and used for the same reaction. All the three catalysts
gave good yields from the first up to the third runs, but the yields decreased in the
Scheme 3. Multicomponent synthesis of 1,4-disubstituted-1H-1,2,3-triazoles using recoverable polymer-
supported azide and CuI. (Figure is provided in color online.)
Scheme 4. Synthesis of symmetrical substituted bis-triazoles using phenacyl bromides and 1,3-diethynyl-
benzene. (Figure is provided in color online.)
Scheme 5. Click cyclization of a-bromo amides and a-bromo esters using polymer-supported azide and
CuI. (Figure is provided in color online.)

REUSABLE CATALYST FOR CLICK CYCLIZATION
2025
Table 3. Recyclability and reusability of polymer-supported azide and CuI
Entry
Loading
Yield (%)a
1
2
3
4
5
1
2
3
4
5
89
90
84
82
78
aYields refer to isolated and pure products.
fourth and fifth runs using amberlyst-supported CuCl and CuBr (Fig. 1). We relate
these observations to the greater oxidation tendency of CuCl and CuBr in the
aqueous medium, which made CuI the best choice to support on amberlyst for
our purposes.
In conclusion, we have developed a simple, benign, and multicomponent
regioselective synthesis of biologically significant 1,4-disubstituted-1H-1,2,3-triazoles
with short times and good yields under polymer-supported catalyst and reagent
conditions. The protocol is applicable to a wide range of a-halo ketones=amides=
esters, and acetylenic compounds and allows the assembly of a diverse set of
1,4-disubstituted-1H-1,2,3-triazoles. The final reaction product can be simply filtered
and separated without the need for a further chromatographic step. In addition, the
spent polymeric reagent can be regenerated and reused several times without
appreciable loss capacity and efficiency. Using of A-21 CuI as catalyst protects the
metal center from oxidation and disproportionation while enhancing its catalytic
activity and makes it a reusable catalyst. Minimal waste generation of this ‘‘user-
friendly’’ process should be beneficial for industrial applications.
Figure 1. Reusability of polymer-supported copper(I) catalysts: Series 1, CuI; series 2, CuCl; and series 3,
CuBr. (Figure is provided in color online.)

2026
J. ALBADI AND M. KESHAVARZ
EXPERIMENTAL
All of the triazole derivatives were prepared by our procedure; their spectro-
scopic and physical data were compared with those of authentic samples. NMR
spectra were recorded in dimethylsulfoxide (DMSO-d6) or CDCl3 on a Bruker
Advanced DPX 500- and 400-MHz instrument spectrometers using tetramethylsi-
lane (TMS) as internal standard. Infrared (IR) spectra were recorded on a
BOMEMMB-Series 1998 Fourier transform (FT)–IR spectrometer.
Preparation of Polymer-Supported Azide Reagent (IRA-910N3)
Amberlite IRA-910N3 was easily prepared from its corresponding chloride
form via ion exchange using 10% NaN3 aqueous solution. Two g of amberlite
IRA-910 chloride (mesh 16–50) were stirred for 6 h in the corresponding solution
(100 mL of 10% NaN3 aqueous solution), filtered off, washed several times with
water, and stirred for an additional 5 min. It was then decanted, washed several times
with water until the supernatant liquid gave a negative azide test with ferric nitrate,
and dried under vacuum at 50 ꢀC.
The exchange capacity of the resin was determined by passing 1 N sodium
chloride solution (50 mL) through the resin (0.3 g) packed in a column. The amount
of sodium salt of the nucleophile in the eluent was then titrated with 0.01 normal
hydrochloric acid using methyl orange as indicator. The exchangeꢁcapacity of
polymer-supported nucleophile was calculated to be 1.5 mmol=g of N3
.
Preparation of the Supported Catalyst (A-21CuI)
Dry amberlyst A-21 (1.0 g, 4.8 mmol amine; mesh 20–50) was added to a sol-
ution of copper(I) iodide (381 mg, 2.00 mmol) in acetonitrile (20 ml) and gently sha-
ken on an orbital stirrer for 24 h. The solvent was filtered, and the resin washed with
CH3CN (2 ꢂ 20 mL) and CH2Cl2 (2 ꢂ 20 mL) and dried under vacuum at 40 ꢀC
over night. The weight increase was 0.31 g (1.63 mmol CuI), which gave a polymer
loading of 1.24 mmol CuI ꢃ gꢁ1. Elemental analysis gave a copper content of
8.32%, indicative of a loading of 1.32 mmol CuI ꢃ gꢁ1
.
The same procedure was used for the preparation of amberlyst-supported
CuCl (A-21CuCl; loading 1.27 mmol CuCl ꢃ gꢁ1) and amberlyst-supported CuBr
(A-21CuBr; loading 1.15 mmol CuBr ꢃ gꢁ1).
Typical Procedure for Multicomponent Synthesis of 1-Phenyl-2-
(4-phenyl-1-h-1,2,3-triazol-1yl)-1-ethanone (1b)
2-Bromo-1-phenyl-1-ethanone (1 mmol) and phenyl acetylene (1 mmol) were
placed together in a round-bottom flask containing 10 mL of acetonitrile. Amberlyst
A-21 CuI (60 mg, loading 1.35 mmol=g) and amberlite IRA-910N3(1 g, loading:
1.5 meq=g) were added at once to the mixture. The suspension was magnetically
stirred under reflux conditions. After completion of the reaction (1 h) as followed
by TLC (n-hexane–ethyl acetate; 4:1), the resins were filtered and washed with

REUSABLE CATALYST FOR CLICK CYCLIZATION
2027
acetonitrile (2 ꢂ 5 mL). The filtrates were evaporated to dryness, and then the solid
residue was recrystallized in hot ethanol to give pure product crystals.
REUSING POLYMER-SUPPORTED CATALYST AND REAGENT
The filtered mixture of resins was washed with 25 mL of distillated water and
stirred for 6 h in the corresponding solution (50 mL of 10% NaN3 aqueous solution)
and dried under vacuum at 50 ꢀC before next run.
1-Phenyl-2-(4-phenyl-1-H-1,2,3-triazol-1yl)-1-ethanone (1b)
1
Mp 136 ꢀC.[34] IR (KBr): 1697 (CO) cmꢁ1. H NMR (400 MHz, DMSO-d6):
d ¼ 8.53(s, 1 H, CHN), 8.11 (d, 2H, J ¼ 8.15 Hz), 7.88 (d, 2H, J ¼ 8.15 Hz),
7.77–7.74 (m, 1 H), 7.63 (t, 2H, J ¼ 7.7 Hz), 7.47 (t, 2H, J ¼ 7.7 Hz), 7.37–7.34 (m,
1 H), 6.27 (s, 2 H, CH2CO). 13C NMR (100 MHz, DMSO-d6): d ¼ 195 (CO), 152.4,
139, 138.2, 134.5, 133.5, 133.2, 132.7, 132.5, 130.1, 126.4, 59.9. HRMS (EI) m=z
found: 263.3 (calculated for C16H13N3O, Mþ, requires: 263.3). Elem. anal. found:
C, 73.00%; H, 4.86%; N, 16.03% (calculated for C16H13N3O: C, 72.92%; H,
4.94%; N, 15.95%).
1-(4-Bromophenyl)-2-(4-phenyl-1H-1,2,3-triazole-1-yl)-1-ethanone
(2b)
1
Mp 145 ꢀC.[34] IR (KBr): 1702 (CO) cmꢁ1. H NMR (400 MHz, DMSO-d6):
d ¼ 8.53(s, 1H), 8.04 (d, 2H J ¼ 8.2 Hz), 7.88–7.86 (m, 2H), 7.71–7.68 (m, 1H),
7.61–7.57 (m, 2H), 7.46–7.42 (m, 2H), 7.31–7.38 (m, 1H), 6.08 (2H, s). 13C-NMR
(100 MHz, DMSO-d6): d ¼ 192.1 (CO), 146.7, 133.6, 132.6, 131.2, 130.7, 129.4,
129.0, 128.4, 125.6, 123.5, 56.5. HRMS (EI) m=z found 341.2 (calculated for
C16H12BrN3O, Mþ, requires: 342.2). Elem. Anal. Found: C, 55.93%; H, 3.45%; N,
12.35% (calculated for C16H12BrN3O: C, 56.11%; H, 3.51%; N, 12.27%).
1-(4-Methoxyphenyl)-2-(4-phenyl-1-H-1,2,3-triazol-1yl)-1-ethanone
(3b)
1
Mp 142 ꢀC.[34] IR (KBr): 1697 (CO) cmꢁ1. H-NMR (500 MHz, DMSO-d6):
d ¼ 8.52 (s, 1H, CHN), 8.08 (d, 2H, J ¼ 8.4 Hz), 7.88 (d, J ¼ 8.4 Hz, 2H), 7.47 (t,
2H, J ¼ 7.6 Hz), 7.35 (t, 1H, J ¼ 7 Hz), 7.14 (d, 2H, J ¼ 8.5 Hz), 6.19 (s; 2H, CH2CO),
3.9 (s, 3H, CH3O). 13C NMR (125 MHz, DMSO-d6): d ¼ 194.95 (CO), 162.12, 141.9,
134.5, 131.66, 131.51, 129.82, 128.71, 126, 123.96, 115.13, 56.58, 56.49. HRMS (EI)
m=z found 295.3 (calculated for C17H15N3O2, Mþ, requires: 294.3). Elem. anal.
found: C, 69.57%; H, 5.06%; N, 14.33% (calculated for C17H15N3O2: C, 69.61%;
H, 5.15%; N, 14.33%).
1-(4-Phenyl-1H-1,2,3-triazole-1-yl)acetone (4b)
Mp 138 ꢀC.[35] IR (KBr): 1729 (CO) cmꢁ1
.
1H NMR (500 MHz, CDCl3):
d ¼ 7.88–7.87 (m, 3H), 7.46 (t, 2H, J ¼ 7.50 Hz), 7.40–7.36 (m, 1H), 2.30 (s, 3H),

2028
J. ALBADI AND M. KESHAVARZ
5.28 (s, 2H)), 2.30 (s, 3H). 13C NMR (125 MHz, CDCl3): d ¼ 199.61, 148.64, 130.77,
129.30, 128.74, 126.22, 121.55, 58.96, 27.66. HRMS (EI) m=z found: 201.2 (calcu-
lated for C11H11N3O, Mþ. requires: 201.2). Elem. anal. found: C, 66.56%; H,
5.57%; N, 20.49% (calculated for C11H11N3O: C, 65.66%; H, 5.51%; N, 20.88%).
Ethyl 2-(4-Phenyl-1H-1,2,3-triazol-1-yl)acetate (5b)
1
Mp 112 ꢀC. IR (KBr): 1755 (CO) cmꢁ1. H NMR (500 MHz, CDCl3): d ¼ 7.9
(s, 1H, CHN), 7.88 (d, 2H, J ¼ 8.4 Hz), 7.46 (t, 2H, J ¼ 7.5 Hz), 7.37 (t, 1H,
J ¼ 7.4 Hz), 5.23 (s, 2H, CH2CO), 4.30 (q, 2H (CH2), J ¼ 7.1 Hz,), 1.33 (t, 3H
(CH3)) J ¼ 7.1 Hz). 13C NMR (125 MHz, CDCl3): d ¼ 166.7 (CO), 148.6, 130.82,
129.26, 128.7, 126.24, 121.4, 62.9, 51.38, 14.5. HRMS (EI) m=z found: 231.3 (calcu-
lated for C12H13N3O2, Mþ requires: 231.3). Elem. anal. found: C, 62.67%; H, 5.30%;
N, 18.06% (calculated for C12H13N3O2: C, 62.33%; H, 5.67%; N, 18.17%).
2-[4-(3-Aminophenyl)-1H-1,2,3-triazol-1yl]-1-phenyl-1-ethanone (6b)
1
Mp 146 ꢀC.[34] IR (KBr): 3420 and 3338 (NH2), 1701 (CO) cmꢁ1. H NMR
(500 MHz, DMSO-d6): d 8.35 ppm (s, 1H), 8.11 (d, 2H, J ¼ 7.46 Hz), 7.75 (t, 1H,
J ¼ 7 Hz,), 7.62 (t, 2H, J ¼ 7.32 Hz), 7.15 (s, 1H), 7.9 (t, 1H, J ¼ 7.6 Hz), 6.98 (d,
1H, J ¼ 7.5 Hz,), 6.56 (d, 1H, J ¼ 7.5 Hz), 6.22 (s, 2H), 5.22 (s, 2H). 13C NMR
(125 MHz, DMSO-d6): d ¼ 193.1 (CO), 149.9, 147.85, 135.13, 135.02, 132.09,
130.27, 129.88, 129.8, 123.46, 114.48, 113.9, 111.38, 56.78.
2-[4-(3-Aminophenyl)-1H-1,2,3-triazol-1yl]-1-(4-methoxyphenyl)-
1-ethanone (7b)
1
Mp 163 ꢀC.[34] IR (KBr): 3424 and 3332 (NH2), 1695 (CO) cmꢁ1. H NMR
(500 MHz, DMSO-d6): d ¼ 8.34 ppm (1H, s), 8.08 (d, 2H, J ¼ 8.9), 7.14 (d, 3H,
J ¼ 8.9,), 7.13 (s, 1H), 7.09 (t, 1H, J ¼ 7.74), 6.97–6.95 (m, 1H), 6.55–6.53 (m, 1H),
6.14 (s, 2H), 5.18 (s, 2H), 3.89 (s, 3H). 13C NMR (125 MHz, DMSO-d6):
d ¼ 191.3, 164.8, 149.9, 147.78, 132.12, 131.48, 130.24, 127.89, 123.48, 115.12,
114.42, 113.85, 111.34, 56.57, 56.40.
2-(4-Phenyl-1H-1,2,3-triazol-1-yl)-1-cyclopentanone (8b)
Mp 147 ꢀC.[35] IR (KBr): 1755 (CO) cmꢁ1 1H NMR (400 MHz, CDCl3):
.
d ¼ 7.89 (s, 1H), 7.84 (d, 2H, J ¼ 7.48 Hz), 7.40–7.44 (m, 2H), 7.35–7.31 (m, 1H),
4.96 (dd, 1H, J1 ¼ 11.4 Hz and J2 ¼ 8.44 Hz), 2.86–2.79 (m, 1H), 2.65–2.42 (m,
3H), 2.36–2.29 (m, 1H), 2.12–2.01 (m, 1H).
1-(Cyclohexan-1-on-2-yl))-4-phenyl-1H-1,2,3-triazole (9b)
Mp 148 ꢀC.[35] TR (KBr): 1719 (CO) cmꢁ1 1H NMR (400 MHz, CDCl3):
.
d ¼ 7.86–7.84 (m, 3H), 7.44–7.41 (m, 2H), 7.35–7.31 (m, 1H), 5.47 (dd,
J1 ¼ 13.14 Hz, J2 ¼ 5.68 Hz, 1H), 2.72–2.52 (m, 3H), 2.29–2.20 (m, 2H), 2.14–2.12
(m, 1H), 2.01–1.81 (m, 2H). HRMS: calcd for C14H15N3O 241.2884, found 241.1719.

REUSABLE CATALYST FOR CLICK CYCLIZATION
2029
2-[4-(1-Hydroxyethyl)-1H-1,2,3-triazole-1-yl)]-1-(4-methoxyphenyl)-
1-ethanone (11b)
IR (KBr): 3503 (OH), 1694 (CO) cmꢁ1. 1H NMR (500 MHz, CDCl3): d ¼ 8.07
(d, 2H, j ¼ 8.74 Hz), 7.87 (s, 1H), 7.13 (d, 2H, J ¼ 8.75 Hz), 6.07 (s, 2H), 5.28 (s, 1H),
4.89–4.86 (m, 1H), 3.89 (s, 3H), 1.45 (d, 3H, j ¼ 8.75 Hz). 13C NMR (125 MHz,
CDCl3): d ¼ 191.38, 164.74, 153.37, 131.42, 127.95, 123.86, 115.08, 62.54, 56.56,
56.18, 24.70.
2-(4-f3-[1-(2-Oxo-2-phenylethyl)1H-1,2,3-triazol-4-yl]phenylg-1H-
1,2,3-triazol-1-yl)-1-phenyl-1-ethanone (13b)
1
Mp ꢄ 300 ꢀC. IR (KBr): 1696 (CO) cmꢁ1. H NMR (500 MHz, DMSO-d6):
d ¼ 8.64 ppm (s, 2H, 2 ꢂ CHN), 8.43 (s, 1H), 8.12 (d, 4H, J ¼ 8.3 Hz), 7.88 (d, 1H,
J ¼ 1.6 Hz), 7.86 (d, 1H, J ¼ 1.6 Hz), 7.76 (t, 2H, J ¼ 7.7 Hz), 7.6 (t, 4H, J ¼ 8.3 Hz),
7.58 (t, 1H, J ¼ 7.7 Hz), 6.29 (s, 2H, CH2O), 6.28 (s, 2H, CH2CO). 13C NMR
(125 MHz, DMSO-d6): d ¼ 193(CO), 146.97, 135.17, 135, 132.29, 130.55, 129.9,
129.1, 125.5, 124.26, 122.7, 56.91.
1-(4-Methoxyphenyl)-2-[4-(3-f1-[2-(4-methoxyphenyl)-
2-oxoethyl]-1H-1,2,3-triazol-4-ylgphenyl)-1H-1,2,3-triazol-1yl]-
1-ethanone (14b)
1
IR (KBr): 1697 (CO) cmꢁ1. H NMR (500 MHz, DMSO-d6): d ¼ 8.5 ppm (s,
2H), 8.41 (s, 1H), 8.11 (d, J ¼ 8.4 Hz, 4H), 7.90 (d, 4H, J ¼ 8.4 Hz), 7.78 (t, 2H,
J ¼ 7.6 Hz), 7.59 (t, 1H, J ¼ 7.6 Hz), 7.15 (d, 2H, J ¼ 8.5 Hz), 6.19 ppm (s, 4H),
3.85 (s, 6H). 13C NMR (125 MHz, DMSO-d6): d ¼ 194.9 (CO), 163.1, 141.9, 133.2,
131.66, 129.82, 128.4, 126, 123.96, 115.2, 56.58, 56.49.
ACKNOWLEDGMENT
We are grateful to the Research Council of Islamic Azad University,
Gachsaran Branch, for financial support.
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