Solid-phase organic synthesis of 1,4-N-vinyl- and 1,4-N-allyl-triazoles with the sulfonate linker

Article abstract of DOI:10.1002/jhet.1857

Polymer-supported 2-azidoethyl sulfonate and 3-azidopropyl sulfonate reagents have been developed and applied to the solid-phase organic synthesis of 1-vinyl- and 1-allyl-1,2,3-triazoles, respectively, by CuI-mediated azide-alkyne cycloadditions and subsequent cleavage from the polymer support through elimination reaction promoted by DBU. The advantages of this new synthetic method include simple operation and high yield of the products, as well as good stability of the reagents.

Full text of DOI:10.1002/jhet.1857

1862
Solid-Phase Organic Synthesis of 1,4-N-Vinyl- and 1,4-N-Allyl-Triazoles
Vol 51
with the Sulfonate Linker
*
Aiying He, Shouri Sheng, Zhenzhong Huang, Li Liu, and Mingzhong Cai
Institutes of Chemistry and Chemical Engineering, Jiangxi Normal University, Jiangxi, Nanchang 330022,
People’s Republic of China
*
E-mail: shengsr@jxnu.edu.cn
Received June 15, 2012
DOI 10.1002/jhet.1857
Published online13 May 2014 in Wiley Online Library (wileyonlinelibrary.com).
Polymer-supported 2-azidoethyl sulfonate and 3-azidopropyl sulfonate reagents have been developed and
applied to the solid-phase organic synthesis of 1-vinyl- and 1-allyl-1,2,3-triazoles, respectively, by CuI-mediated
azide-alkyne cycloadditions and subsequent cleavage from the polymer support through elimination reaction
promoted by DBU. The advantages of this new synthetic method include simple operation and high yield of
the products, as well as good stability of the reagents.
J. Heterocyclic Chem., 51, 1862 (2014).
INTRODUCTION
and a versatile linker [3c,3d]. Previous and recent reports
from Kurth and co-workers [9], Lam’s research group [10],
other laboratories [11], and ours [12] have developed
sulfone-linking strategies for SPOS methods to explore
sulfone-based chemical transformations. As a part of our
ongoing research program focused on the use a versatile
traceless sulfone linker in SPOS, we herein have explored
an efficient SPOS of 1,4-N-vinyl- and 1,4-N-allyl- triazoles
with the sulfonate linker. To our knowledge, this is a previ-
ously unreported method, which is shown in the Scheme 1.
Compared with the reported protocols, the advantages of
the present method are the use of readily available precursors,
easy work-up procedure, simple monitoring technology, and
high yields of the products.
Combinatorial chemistry, together with solid-phase organic
synthesis (SPOS) technique, provides an efficient methodol-
ogy for the high-speed synthesis of structurally diverse
compounds for the drug discovery community [1]. The
SPOS approach offers the advantages of driving the reaction
to completion by the use of excess polymeric reagents and
easy isolation of products by filtration from the solid support
[2]. Heterocyclic compounds have attracted considerable
interest because of their broad range of biological activities.
Therefore, an increasing number of pharmaceutically useful
heterocyclic compounds have been prepared using SPOS
methodologies [3]. 1,2,3-Triazoles, as one of the most useful
nitrogen-containing heterocycles [4], have received much
attention because of their wide applications in many research
fields such as materials, chemical, and biological sciences [5].
Owing to their importance, numerous synthesis approaches
for this kind of compounds have been developed [6,7].
However, there are only a paucity of synthetic approaches
for 1-vinyl- and 1-ally-1,2,3-triazoles [8]. Although some
of these methods are satisfactory in terms of yield, most of
the reported methods suffer at least from one of the following
disadvantages: the use of expensive catalyst and reagents,
tedious experimental procedures, long reaction time, or use
of an additional ultrasound irradiation. As a result, a facile
preparation of 1-vinyl- and 1-allyl-1,2,3-triazoles for lead
discovery is highly desirable. Sulfinate-functionalized resins
have been efficiently prepared and utilized in SPOS, and the
resulting sulfone linker has been found to be both a robust
RESULTS AND DISCUSSION
Firstly, polymer-supported sulfonyl chloride 1 was pre-
pared from a commercially available 2% cross-linked benze-
nesulfonic acid resin by treatment it with thionyl chloride in
N,N-dimethylformamide (DMF) according to a literature
procedure [13]. The loading of this resin on the basis of
chlorine analysis was 4.1 g/mmol. In the presence of triethy-
lamine, 2-azidoethanol or 3-azidopropanol was reacted with
sulfonyl chloride resin 1 to afford 2-azidoethyl sulfonate
ester resin 2a and 3-azidopropyl sulfonate ester resin 2b
(>98% yield, determined by elementary analysis of
the nitrogen: azide loading = 3.35 mmol/g for 2a and
3.20 mmol/g for 2b), respectively, which were monitored
© 2014 HeteroCorporation

November 2014
Solid-Phase Organic Synthesis of 1,4-N-Vinyl- and 1,4-N-Allyl-Triazoles
1863
with the Sulfonate Linker
Scheme 1. Solid-phase organic synthesis of 1,4-N-vinyl- and 1,4-N-allyl- triazoles.
N3
HO
R, CuI, DIPEA
DMF/THF, rt
m
N3
m
SO2
O
SO2Cl
Et3N, CH2Cl2, rt,
1
2a (m=1), 2b (m=2)
R
DBU, NaI
R
SO2
O
N
N N
n
N
N
DMF, 130 oC
N
n
3a (n=0), 3b (n=1)
4a (n=0), 4b (n=1)
by the infrared absorption band at 1370 cmÀ1 (S–O stretch
of –SO2C1) that was shifted near to 1350 cmÀ1 (–SO2–O–),
as well as by the appearance of a characteristic azido absorp-
in Table 1, terminal alkynes including alkyl (entries 1, and 7)
and aryl (entries 2–6 and 8–12) alkynes could perform effi-
ciently with good yields (80–87%) of products (4aa–4bf).
tion near 2100cmÀ1
.
In the next step, [3 + 2] cycloaddition reaction of resin 2
with various terminal alkynes, the key for the success of
this protocol, was then investigated. Recently, the advan-
tages of using the “click” chemistry concept and specifi-
cally, the Cu(I)-catalyzed alkyne–azide cycloaddition
(CuAAC) as a powerful tool in the design and synthesis
of 1,4-disubstituted-1H-1,2,3-triazoles exclusively have
been demonstrated [6,7]. On the basis of these studies, phenyl
acetylene was chosen here for the template reaction with resin
2a, and reaction conditions such as solvents (THF, DMF, and
CH2Cl2), catalyst (CuSO4/sodium ascorbate or CuI), amount
of catalyst, and reaction time were evaluated. After a consid-
erable number of experiments, the 1,3-dipolar cycloaddition
of resin 2a with phenyl acetylene proceeded smoothly in
DMF/THF in the presence of diisopropylethyl amine and
catalytic amounts of CuI at room temperature for 10 h to
afford the 2-triazolylethyl sulfonate resin (3aa), which can
also be monitored by the IR spectrum conveniently and
precisely, in which the characteristic signal of the azido group
(2100 cmÀ1) has been distinctly shrunk after 5 h of reaction
time, and then disappeared completely for another 5 h of reac-
tion time.
Finally, the cleavage conditions with bases such as pyr-
idine and DBU in various solvents (MeCN, DMF, THF,
and 1,4-dioxane) in different reaction temperature and time
were examined, and optimal result was obtained by treat-
ing resin 3aa in DMF with DBU in the presence of NaI
at 130ꢀC for 2 h, yielding the corresponding 4-phenyl-
1-vinyl-1H-1,2,3-triazole (4aa) in 86% yield on the basis
of the loading of resin 2a (entry 1, Table 1).
With an optimized CuAAC and base-catalyzed elimina-
tion cleavage protocol, the generality of the method were
further evaluated using a variety of terminal alkynes with
resin 2a and 2b, and the corresponding target compounds,
1,4-N-vinyl-triazoles (4aa–4af), and 1,4-N-allyl-triazoles
(4ba–4bf) were obtained, respectively. As can be observed
CONCLUSIONS
In summary, we have developed a facile method for the
solid-phase synthesis of 1,4-N-vinyl- and 1,4-N-allyl-
triazoles by Cu(I)-catalyzed 1,3-dipolar cycloaddition
reaction of polymer-bound 2-azidoethyl and 3-azidopropyl
sulfonate esters with terminal alkynes and subsequent
base-promoted elimination reaction, respectively. This
method provides a novel access to 1,4-N-vinyl- and
1,4-N-allyl- triazoles in good yields with simplification
of product work-up.
EXPERIMENTAL
1
Melting points were uncorrected. H and 13C NMR spectra
were recorded on a Bruker Avance (400 MHz) spectrometer
(Bruker Corp., Billerica, MA), using CDCl3 as the solvent and
TMS as internal reference. IR spectra were taken on a Perkin-
Elmer SP One FTIR spectrophotometer (PerkinElmer, Inc.,
Table 1
Yields of 1,4-N-vinyl- and 1,4-N-allyl-triazoles (4aa–4bf).
Entry
R
Product
Yielda (%)
1
2
3
4
5
6
7
8
C6H5
n-C3H7
n-C4H9
CH2OH
CH2OCH3
CO2C2H5
C6H5
n-C3H7
n-C4H9
CH2OH
CH2OCH3
CO2C2H5
4aa
4ab
4ac
4ad
4ae
4af
4ba
4bb
4bc
4bd
4be
4bf
86
83
84
80
86
85
88
84
83
80
87
85
9
10
11
12
aIsolated yields based on the azide loading of the resin 2.
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

1864
A. He, S. Sheng, Z. Huang, L. Liu, and M. Cai
Vol 51
Waltham, MA). Microanalyses were performed with a Carlo Erba
1106 Elemental Analyzer (Milan, Italy). Used was 2% cross-linked
benzenesulfonic acid resin for the preparation of sulfonyl chloride
resin according to the reported method [13]. 2-Azidoethanol and
3-Azidopropanol were prepared by reaction of 2-chloroethanol
and 3-chloropropanol with sodium azide according to literature
procedure, respectively [8f,14]. The other starting materials were
purchased from commercial sources and used without further
purification. THF was newly stilled from sodium-benzophenone,
and DMF was purified by distillation under reduced pressure over
calcium hydride prior to use.
Calcd. for C8H13N3: C, 63.54; H, 8.67; N, 27.79. Found: C,
63.43; H, 8.62; N, 27.86.
4-Hydroxymethyl-1-vinyl-1H-1,2,3-triazole (4ad).
Colorless
oil; 1H NMR (400MHz, CDCl3): d 7.52 (s, 1H), 7.30 (dd,
J = 15.6, 8.7 Hz, 1H), 5.52 (dd, J = 15.6, 1.6 Hz, 1H), 5.01 (dd,
J = 8.7, 1.6 Hz, 1H), 4.78 (s, 2H), 2.41 (br s, 1H); 13C NMR
(100MHz, CDCl3): d 148.2, 130.4, 121.6, 104.5, 56.1; IR (film):
n = 3304, 3060, 2983, 1644, 1146, 1037, 886, 720cmÀ1; Anal.
Calcd. for C5H7N3O: C, 47.99; H, 5.64; N, 33.58. Found: C,
47.92; H, 5.57; N, 33.64.
4-Methoxymethyl-1-vinyl-1H-1,2,3-triazole (4ae).
Colorless
1
oil; H NMR (400MHz, CDCl3): d 7.54 (s, 1H), 7.30–7.28 (m,
1H), 5.52 (dd, J = 15.6, 1.6 Hz, 1H), 5.00 (dd, J =8.6, 1.6 Hz,
1H), 4.52 (s, 2H), 3.01 (s, 3H); 13C NMR (100 MHz, CDCl3): d
147.8, 130.4, 118.6, 102.6, 65.6, 55.0; IR (film): n = 3055, 2895,
Preparation of resin 2.
Under a nitrogen atmosphere,
tosulfonylchlorideresin1(2.0mmol,4.1 mmol/g)swelledinCH2Cl2
(10 mL) for 1 h were added 2-azidoethanol or 3-azidopropanol
(8.0mmol), and triethylamine (1.1mL, 8.0 mmol), and the resulting
mixturewasstirredovernightatroomtemperature.Afterthis,theresin2
was collected by filtration and washed successively with CH2Cl2
(2Â 10mL), H2O (2 Â 10mL), MeOH (2 Â 10mL), and CH2Cl2
(2Â 10mL)andthendriedinvacuotogive2aspaleyellowresin.2a:
azide loading = 3.35 mmol/g; IR (KBr): n = 2100 (–N3), 1350
(–SO2–O–) cmÀ1; 2b: azide loading = 3.20 mmol/g; IR (KBr):
1644, 2894, 1466, 1368, 1224, 1124, 1079, 1018, 924, 772cmÀ1
;
Anal. Calcd. for C6H9N3O: C, 51.79; H, 6.52; N, 30.20. Found:
C, 61.72; H, 6.48; N, 30.27.
Ethyl 1-vinyl-1H-1,2,3-triazole-4-carboxylate (4af). Colorless
oil; 1H NMR (400 MHz, CDCl3): d 8.54 (s, 1H), 7.41 (dd, J= 16.0,
1.8 Hz, 1H), 5.52 (dd, J= 16.0, 1.8 Hz, 1H), 5.21 (dd, J =8.8, 1.8Hz,
1H), 4.45 (q, J= 7.2 Hz, 2H), 1.39 (t, J = 7.2 Hz, 3H); 13C NMR
(100 MHz, CDCl3): d 160.5, 140.5, 130.7, 128.4, 118.2, 61.6,
14.1; IR (film): n = 3198, 2927, 1725, 1644, 1450, 1378, 1230,
1170, 1085, 1025, 990, 915 cmÀ1; Anal. Calcd. for C7H9N3O2: C,
50.29; H, 5.43; N, 25.14. Found: C, 50.22; H, 5.38; N, 25.22.
n = 2102(–N3),1351(–SO2–O–)cmÀ1
General procedure for the preparation of 1,4-N-vinyl- and
1,4-N-allyl- triazoles 4. Resin 2 (2.0 mmol) was swelled in
.
THF/DMF (15 mL, 2:1) at room temperature for 30 min under
nitrogen. Then alkyne (8.0 mmol), CuI (19.0 mg; 0.1 mmol), and
diisopropylethyl amine (1.0 mL, 7.7 mmol) were added, and the
mixture was stirred at room temperature. This progression of the
reaction was monitored by IR spectroscopy. After disappearance
of the signal near 2010cmÀ1, the suspension was filtered through
the vessel frit, and the resin was washed successively with H2O
(2 Â 10 mL), MeOH (2 Â 10 mL), and CH2Cl2 (2 Â 10 mL) and
dried in vacuo to give 3. The resin 3 was then swelled in DMF
(15 mL) for 30 min under a nitrogen atmosphere, and NaI (0.9 g,
0.6 mmol) and DBU (0.6 g, 4.0 mmol) were added this
suspension mixture, which was heated to 130ꢀC and kept with
this temperature for 2 h. Upon completion, the mixture was
cooled, and the resin was collected by filtration and washed
with CH2Cl2 (3 Â 10 mL). The filtrate was washed with water
(2 Â 30 mL), dried over magnesium sulfate, and concentrated to
afford products 4aa–4bf, which were further purified via flash
column chromatography eluted with hexane/ethyl acetate for
their structure analysis.
1-Allyl-4-phenyl-1H-1,2,3-triazole (4ba) [8a,8b].
White
solid, mp 56–57ꢀC; 1H NMR (400 MHz, CDCl3): d 7.85–7.82
(m, 2H), 7.77 (s, 1H), 7.45–7.38 (m, 3H), 6.10–6.08 (m, 1H),
5.41–5.39 (m, 2H), 5.04–5.01 (m, 2H); IR (KBr): n = 3130,
2972, 1645, 1449, 1240, 1015, 995, 908 cmÀ1
.
1-Allyl-4-propyl-1H-1,2,3-triazole (4bb) [8b]. Colorless oil;
1H NMR (400 MHz, CDCl3): d 7.31 (s, 1H), 6.04–6.02 (m, 1H),
5.35–5.31 (m, 2H), 4.98–4.95 (m, 2H), 2.72–2.69 (t, J = 7.6 Hz,
2H), 1.71–1.68 (m, 2H), 1.00 (t, J = 7.0 Hz, 3H); IR (film):
n = 3129, 2965, 1644, 1368, 1240, 1036, 994, 910 cmÀ1
.
1-Allyl-4-butyl-1H-1,2,3-triazole (4bc) [8b]. Colorless oil; 1H
NMR (400 MHz, CDCl3): d 7.31 (s, 1H), 6.04–6.01 (m, 1H), 5.33–
5.28 (m, 2H), 4.97–4.94 (m, 2H), 2.72 (t, J = 7.5Hz, 2H), 1.68–1.64
(m, 2H), 1.41–1.35 (m, 2H), 0.97 (t, J = 7.2Hz, 3H); IR (film):
n = 3128, 2965, 1645, 1374, 1240, 1040, 998, 910, 725 cmÀ1
.
1-Allyl-4-hydroxymethyl-1H-1,2,3-triazole (4bd) [8b]. Colorless
oil; 1H NMR (400 MHz, CDCl3): d 7.47 (s, 1H), 6.03–6.01
(m, 1H), 5.34–5.31 (m, 2H), 4.97–4.94 (m, 2H), 4.79 (s, 2H), 2.52
(br s, 1H); IR (film): n = 3330, 1645, 1572, 1475, 1276, 1038, 992,
922 cmÀ1; Anal. Calcd for C6H9N3O: C, 51.79; H, 6.52; N, 30.20.
Found: C, 61.71; H, 6.48; N, 30.25.
4-Phenyl-1-vinyl-1H-1,2,3-triazole (4aa) [8f]. White solid, mp
1
50–51ꢀC; H NMR (400 MHz, CDCl3): d 8.01 (s, 1H), 7.82–7.70
(m, 2H), 7.62–7.40 (m, 3H), 7.35 (dd, J= 15.8, 8.7 Hz, 1H), 5.69
(dd, J= 15.8, 1.8 Hz, 1H), 5.15 (dd, J=8.7, 1.8Hz, 1H); IR (KBr):
1-Allyl-4-methoxymethyl-1H-1,2,3-triazole (4be).
Colorless
n = 3133, 1645, 1460, 1230, 1010, 952, 765, 690 cmÀ1
.
oil; 1H NMR (400 MHz, CDCl3): d 7.55 (s, 1H), 6.05–6.02
(m, 1H), 5.36–5.32 (m, 2H), 4.99–4.96 (m, 2H), 4.50 (s, 2H), 2.99
(s, 3H); 13C NMR (100 MHz, CDCl3): d 148.6, 131.0, 120.8,
119.6, 65.5, 54.9, 52.7; IR (film): n = 3035, 2893, 1645, 1475,
1368, 1254, 1068, 994, 912 cmÀ1; Anal. Calcd for C7H11N3O: C,
54.89; H, 7.24; N, 27.43. Found: C, 54.83; H, 7.19; N, 27.50.
Ethyl 1-allyl-1H-1,2,3-triazole-4-carboxylate (4bf). Colorless
oil; 1H NMR (400 MHz, CDCl3): d 7.90 (s, 1H), 6.05–6.02 (m, 1H),
5.33–5.31 (m, 2H), 5.00–4.97 (m, 2H), 4.29 (q, J = 7.2 Hz, 2H),
1.33 (t, J = 7.2Hz, 3H); 13C NMR (100MHz, CDCl3): d 160.8,
148.1, 130.5, 121.1, 119.8, 61.2, 50.8, 13.9; IR (flim): n = 3060,
1726, 1645, 1420, 1270, 1243, 1138, 1025, 995, 910 cmÀ1; Anal.
Calcd for C8H11N3O2: C, 53.03; H, 6.12; N, 23.19. Found: C,
53.00; H, 6.11; N, 23.26.
4-Propyl-1-vinyl-1H-1,2,3-triazole (4ab) [8f]. Colorless oil;
1H NMR (400 MHz, CDCl3): d 7.55 (s, 1H), 7.23 (dd, J = 16.0,
8.0 Hz, 1H), 5.52 (dd, J = 16.0, 1.8 Hz, 1H), 5.00 (dd, J = 8.0,
1.8 Hz, 1H), 2.68–2.65 (t, J = 7.6 Hz, 2H), 1.63–1.60 (m, 2H),
0.94 (t, J = 7.3Hz, 3H); IR (film): n = 3135, 2960, 1648, 1375,
1040, 958, 725 cmÀ1
4-Butyl-1-vinyl-1H-1,2,3-triazole (4ac).
.
Colorless oil; 1H
NMR (400 MHz, CDCl3): d 7.57 (s, 1H), 7.25 (dd, J = 15.8,
8.8 Hz, 1H), 5.56 (dd, J = 15.8, 1.8 Hz, 1H), 5.03 (dd, J = 8.8,
1.8 Hz, 1H), 2.72 (t, J = 7.7 Hz, 2H), 1.70–1.60 (m, 2H), 1.44–
1.33 (m, 2H), 0.99 (t, J = 7.4 Hz, 3H); 13C NMR (100 MHz,
CDCl3): d 148.7, 130.2, 118.3, 103.5, 31.5, 25.4, 22.5, 13.8; IR
(film): n = 3130, 2963, 1647, 1041, 1376, 954, 722 cmÀ1; Anal.
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

November 2014
Solid-Phase Organic Synthesis of 1,4-N-Vinyl- and 1,4-N-Allyl-Triazoles
1865
with the Sulfonate Linker
Acknowledgments. We gratefully acknowledge financial support
from the National Natural Science Foundation of China
(No. 21062007) and the Research Program of Jiangxi Province
Department of Education (No. GJJ10385, GJJ11380, and GJJ12201).
(d) Sreedhar, B.; Reddy, P. S.; Krishna, V. R. Tetrahedron Lett 2007,
48, 5831; (e) Fletcher, J. T.; Walz, S. E.; Keeney, M. E. Tetrahedron Lett
2008, 49, 7030; (f) Wu, L.; Xie, Y.; Chen, Z.; Niu, Y.; Liang, Y. Synlett
2009, 1453; (g) Dabiri, M.; Salehi, P.; Bahramnejad, M.; Sherafat, F. J
ꢀ
Comb Chem 2010, 12, 638; (h) Kolarovic, A.; Schnürch, M.; Mihovilovic,
M. D. J Org Chem 2011, 76, 2613; (i) Xu, M.; Kuang, C. X.; Wang, Z.;
Yang, Q.; Jiang, Y. B. Synthesis 2011, 223; (j) McIntosh, M. L.;
Johnston, R. C.; Pattawong, O.; Ashburn, B. O.; Naffziger, M. R.;
Cheong, P. H.-Y.; Carter, R. G. J Org Chem 2012, 77, 1101.
[8] (a) Sreedhar, B.; Reddy, P. S. Synth Commun 2007, 37, 805;
(b) Fletcher, J. T.; Keeney, M. E.; Walz, S. E. Synthesis 2010, 3339; (c)
Reddy, P. S.; Ravi, V.; Sreedhar, B. Tetrahedron Lett 2010, 51, 4037;
(d) Alonso, F.; Moglie, Y.; Radivoy, G.; Yus, M. Eur J Org Chem
2010, 1875; (e) Takizawa, K.; Nulwala, H.; Thibault, R. J.; Lowenhielm,
P.; Yoshinaga, K.; Wooley, K. L.; Hawker, C. J. J Polym Sci Part A
Polym Chem 2008, 46, 2897; (f) Nulwala, H.; Burke, D. J.; Khan, A.;
Serrano, A.; Hawker, C. J. Macromolecules 2010, 43, 5474.
[9] (a) Cheng, W. C.; Lin, C. C.; Kurth, M. J. Tetrahedron Lett
2002, 43, 2967; (b) Cheng, W. C.; Kurth, M. J. J Org Chem 2002, 67,
4387; (c) Hwang, S. H.; Olmstead, M. M.; Kurth, M. J. J Comb Chem
2004, 6, 142.
REFERENCES AND NOTES
[1] (a) Kundu, B. Curr Opin Drug Discovery Dev 2003, 6, 815;
(b) Ziegert, R. E.; Torang, J.; Knepper, K.; Brase, S. J Comb Chem
2005, 7, 147; (c) Feliu, L.; Vera-Luque, P.; Albericio, F.; Alvarez, M. J
Comb Chem 2009, 11, 175.
[2] Döwald, F. Z. Organic Synthesis on Solid Phase: Supports,
Linkers, Reactions (2nd ed.); Wiley-VCH: Weinheim, 2002; pp 1–44.
ꢀ
[3] (a) Franzen, R. G. J Comb Chem 2000, 2, 195; (b) Krchnák,
V.; Holladay, M. W. Chem Rev 2002, 102, 61; (c) Blaney, P.; Grigg,
R.; Sridharan, V. Chem Rev 2002, 102, 2607; (d) McAllister, L. A.;
McCormick, R. A.; Procter, D. J. Tetrahedron 2005, 61, 11527.
[4] Fan, W. Q.; Katritzky, A. R. In Comprehensive Heterocyclic
Chemistry II; Katritzky, A. R., Rees, C. W., Scriven, C. W. V., Eds.;
Elsevier: Oxford, 1996; Vol. 4, pp 1–126.
[5] (a) Krasiski, A.; Radi, Z.; Manetsch, R.; Raushel, J.; Taylor,
P.; Sharpless, K. B.; Kolb, H. C. J Am Chem Soc 2005, 127, 6686; (b)
Binder, W. H.; Kluger, C. Curr Org Chem 2006, 10, 1791; (c) Suijkerbuijk,
B. M. J. M.; Aerts, B. N. H.; Dijkstra, H. P.; Lutz, M.; Spek, A. L.; Koten,
G. V.; Gebbink, R. J. M. K. Dalton Trans 2007, 1273.
[6] For recent reviews, see: (a) Bock, V. D.; Hiemstra, H.; van
Maarseveen, J. H. Eur J Org Chem 2006, 51; (b) Gil, M. V.; Arevalo,
M. G.; Lopez, O. Synthesis 2007, 1589; (c) Moses, J. E.; Moorhouse,
A. D. Chem Soc Rev 2007, 36, 1249; (d) Meldal, M.; Tornøe, C. W.
Chem Rev 2008, 108, 2952; (e) Amblard, F.; Cho, J. H.; Schinazi, R. F.
Chem Rev 2009, 109, 4207; (f) Kappe, C. O.; Van der Eycken, E. Chem
Soc Rev 2010, 39, 1280; (g) Hein, J. E.; Fokin, V. V. Chem Soc Rev
2010, 39, 1302.
[7] For recent selected examples on the preparation of 1,2,3
triazoles: (a) Rostovtsev, V. V.; Green, L. G.; Fokin, V. V.; Sharpless,
K. B. Angew Chem Int Ed 2002, 41, 2596; (b) Zhang, L.; Chen, X.;
Xue, P.; Sun, H. H. Y.; Williams, I. D.; Sharpless, K. B.; Fokin, V. V.;
Jia, G. J Am Chem Soc 2005, 127, 15998; (c) Alexandru, G.; Erick, C.
Y.; Joachim, H.; Willi, B.; Narasaiah, B.; Oliver, R. Synlett 2006, 2767;
[10] (a) Chen, Y.; Lam, Y. L.; Lai, Y. H. Org Lett 2003, 5, 1067;
(b) Li, W. W.; Lam, Y. L. J Comb Chem 2005, 7, 721; (c) Gao, Y.-N.;
Lam, Y.-L. Org Lett 2006, 8, 3283.
[11] (a) Huang, W.; Cheng, S.; Sun, W. Tetrahedron Lett 2001,
42, 1973; (b) D’herde, J. N. P.; De Clercq, P. J. Tetrahedron Lett
2003, 44, 6657; (c) Hwang, J. Y.; Choi, H.-S.; Lee, D.-H.; Gong,
Y.-D. J Comb Chem 2005, 7, 816; (d) McAllister, L. A. Turner, K.
L.; Brand, S.; Stefaniak, M.; Procter, D. J. J Org Chem 2006, 71,
6497; (e) Xie, J. W.; Sun, J.; Zhang, G. L.; Houghten, R. A.; Yu,
Y. P. J Comb Chem 2007, 9, 566; (f) Chang, Y.-F.; Jiang, Y.-R.;
Cheng, W.-C. Tetrahedron Lett 2008, 49, 543.
[12] (a) Sheng, S.-R.; Huang, P.-G.; Zhou, W.; Luo, H.-R.; Lin,
S.-Y.; Liu, X.-L. Synlett 2004, 2603; (b) Liu, X.-L.; Sheng, S.-R.; Zhou,
W.; Wang, Q.-Y.; Zhang, X.-L.; Gong, B. Synth Commun 2007, 37,
119; (c) Sheng, S.-R.; Xu, L.; Zhang, X.-L.; Liu, X.-L.; Wei, M.-H. J
Comb Chem 2006, 8, 805.
[13] ten Holte, P.; Thijs, L.; Zwanenburg, B. Tetrahedron Lett
1998, 39, 7407.
[14] Sumerlin, B. S.; Tsarevsky, N. V.; Louche, G.; Lee, R. Y.;
Matyjaszewski, K. Macromolecules 2005, 38, 7540.
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet