Synthesis of Novel Polyazinyl-Substituted Triazolopyridines from [1,2,3]Triazolo[1,5-a]pyridines

Article abstract of DOI:10.1055/s-0036-1588525

A series of 7-azinyl-substituted triazolopyridines and 3-(6-azinyl-substituted 2-pyridyl)triazolopyridines were synthesized by addition of the corresponding 3-substituted 7-lithiotriazolopyridine to pyrimidine, pyrazine, pyridazine, and 1,3,5-triazine respectively, followed by hydrolysis and oxidation.

Full text of DOI:10.1055/s-0036-1588525

SYNTHESIS
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© Georg Thieme Verlag Stuttgart · New York
2017, 49, A–H
paper
A
en
R. Adam et al.
Paper
Synthesis
Synthesis of Novel Polyazinyl-Substituted Triazolopyridines from
[1,2,3]Triazolo[1,5-a]pyridines
R
Rosa Adam
Belén Abarca*
N
N
N
N
Rafael Ballesteros
R = H, Me, Ph
R
Departamento de Química Orgánica, Facultad de Farmacia,
Universidad de Valencia, Avda. Vicente Andrés Estellés s/n,
46100 Burjassot, Valencia, Spain
Nn
Lithiation
reaction
N
N
17 new compounds
N
N
N
N
Belen.abarca@uv.es
Nn
N
R = 2-Py
N
N
R = H, Me, Ph, 2-Py
Nn
5 new compounds
Received: 26.05.2017
Accepted after revision: 05.07.2017
Published online: 02.08.2017
Remarkably [1,2,3]triazolo[1,5-a]pyridines 1 give regi-
oselective lithiation in the 7-position,20 and the corre-
sponding 7-lithiotriazolopyridines can react with different
electrophiles. Using this methodology we have recently re-
ported the synthesis of two new triazolopyridines contain-
ing diazine rings that are fluorescent tridentate ligands21
(Scheme 1).
DOI: 10.1055/s-0036-1588525; Art ID: ss-2017-t0358-op
Abstract A series of 7-azinyl-substituted triazolopyridines and 3-(6-azi-
nyl-substituted 2-pyridyl)triazolopyridines were synthesized by addition
of the corresponding 3-substituted 7-lithiotriazolopyridine to pyrimi-
dine, pyrazine, pyridazine, and 1,3,5-triazine respectively, followed by
hydrolysis and oxidation.
R
Key words triazolopyridines, diazines, triazines, lithiation reactions,
polynitrogenated ligands
N
N
N
pyrazine
R
R
N
R = Ph
Nitrogenated compounds containing two or three
azines in their structure are highly relevant scaffolds in dif-
ferent fields.1 The location of nitrogen atoms in the azide
determines different applications for these compounds. For
example 2,2′-bipyridine has interesting properties in coor-
dination chemistry or as a catalyst,2 whereas 4,4′-bipyri-
dine is also applied in photochemistry.3 Another relevant
example is terpyridine with applications in a large variety
of domains.4
N
N
N
N
N
N
R = Py
N
N
Li
N
1
pyridazine
N
N
N
N
Scheme 1
In recent years, our research has focused on the chemis-
try and potential applications of [1,2,3]triazolo[1,5-a]pyri-
dines and their derivatives.5 1,2,3-Triazole moieties are con-
sidered privileged scaffolds in medicinal chemistry,6,7 as
these structures are present in molecules described to have
antibiotic,8,9 antineoplastic,10,11 anti-HIV,12 or antifungal ac-
tivities.13 Furthermore, some molecules containing 1,2,3-
triazole structure have been described as antileishmanial
agents.14–17 Recently, we reported the first [1,2,3]triazo-
lo[1,5-a]pyridine derivatives with leishmanicidal activity.18
On the other hand, triazolopyridines and derivatives are
also very good ligands in supramolecular chemistry. Hence,
several of these molecules have been described as fluores-
cent sensors and compounds with interesting magnetic
properties.19
With the aim of obtaining new triazolopyridine deriva-
tives, potentially active against leishmaniasis, and/or with
interesting coordination properties, we have applied the
same methodology to the synthesis of 22 novel polyazinyl
triazolopyridines. In this study we present the reaction of
lithio derivatives of [1,2,3]triazolo[1,5-a]pyridines 1 using
four different azines as electrophiles.22
Bi- or terheterocycles of the azinyl-substituted triazol-
opyridine-type have been synthesized by nucleophilic ad-
dition of 7-lithiotriazolopyridines to azines. The identity
and purity of all these new compounds were confirmed by
HRMS, 1H and 13C NMR.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2017, 49, A–H

B
R. Adam et al.
Paper
Synthesis
The 7-lithio derivatives of triazolopyridines 1a–d were
obtained by regioselective lithiation using nBuLi in toluene
at –40 °C. Addition of lithium derivatives of 1a–c to the
azines shown in Figure 1 occurs in the most electrophilic
position of the azine, i.e. the position ortho to nitrogen.
These adducts were hydrolyzed and oxidized by aqueous
KMnO4 solution and finally afforded azinyl derivatives 2
(Scheme 2).
R
R
N
N
N
N
N
N
N
N
N
N
N
O
N
N
N
N
N
N
N
H2N
N
N
N
10
9
7a R = H
8a R = H
8b R = CH3
7b R = CH3
7c R = Ph
N
N
N
N
N
N
N
N
N
N
N
N
N
pyrimidine
pyridazine
pyrazine
1,3,5-triazine
N
N
Figure 1 Selected azines
16
Figure 3 Secondary products
R
R
N
1. nBuLi, toluene,
–40 °C
N
N
N
N
N
N
substituents R′ are present and B-type structures when
electron-withdrawing substituents R′ are present (Scheme
3).23
2.
N
Nn
Nn
1a R = H
2
3. NH4Cl (aq)
4. KMnO4 (aq)
1b R = CH3
1c R = Ph
Scheme 2
N
N
N
Compounds 3a–c, 4a–c, 5a–c, and 6a–c were obtained
in low to moderate yields (Figure 2). All products, except
3b,c and 5b,c, precipitated when the crude product was
treated with ethyl acetate.
N
N
R'
N
N
N
N
N
N
N
R'
R'
A
B
Scheme 3 Tautomeric equilibrium of 1d derivatives
R
R
R
R
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Hence, when azines were reacted with the 7-lithio de-
rivative of 1d (Scheme 4), in all cases the ring-chain-ring
tautomeric equilibrium resulted in compounds of structure
B. Thus, 3-(6-azinyl-substituted 2-pyridyl)triazolopyridines
12–15 were obtained, as the electron-withdrawing nature
of the azines made the diazo compound intermediate cy-
clize with the less electron-deficient pyridine (Figure 4). All
compounds, except 14, precipitated pure when the crude
product was treated with ethyl acetate. In the reaction with
pyrimidine, traces of compound 16 were obtained (Figure
3). It is interesting to note that these compounds have ter-
pyridine-like structures which implies a great capacity to
coordinate with metals.19b
N
N
N
N
N
N
3a R = H (21%)
3b R = CH3 (25%)
3c R = Ph (15%)
4a R = H (17%)
4b R = CH3 (30%)
4c R = Ph (61%)
5a R = H (14%)
5b R = CH3 (21%) 6b R = CH3 (42%)
5c R = Ph (11%) 6c R = Ph (21%)
6a R = H (10%)
Figure 2 Azinyl-substituted triazolopyridines 3–6
In the reactions with pyrimidine and pyridazine, except
in the reaction of 1c with pyridazine, traces of secondary
products 7a–c and 8a,b were obtained originating from the
attack of the corresponding 7-lithiotriazolopyridine at the
2- and 4-positions of the pyrimidine and pyrazine, respec-
tively. In addition, reaction of 3-methyltriazolopyridine 1b
with pyrimidine also afforded traces of compound 9 (2.5%).
When triazolopyridine 1a was reacted with 1,3,5-triazine,
amide 10, arising from the opening of the triazine ring, was
obtained in very low yield (Figure 3).
N
1. nBuLi, toluene,
–40 °C
N
N
N
N
N
N
2.
N
N
Nn
N
Ring-chain isomerization is a well-known property of
3-(2-pyridyl)triazolopyridine 1d (R = 2-pyridyl). This effect
is observed when compound 1d is substituted in the 7-po-
sition providing A-type structures when electron-donating
11
1d
Nn
3. NH4Cl (aq)
4. KMnO4 (aq)
Scheme 4 3-(6-Azinyl-substituted 2-pyridyl)triazolopyridine synthesis
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2017, 49, A–H

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R. Adam et al.
Paper
Synthesis
7-(Pyrimidin-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (3a) and 7-(Py-
rimidin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (7a)
N
N
N
N
Following the general procedure using 1a (0.2 g), 1.6 M nBuLi (1.4
mL), toluene (85 mL), pyrimidine (0.4 mL), and KMnO4/H2O (0.29 g/50
mL). The crude was treated with EtOAc, the yellow solid that precipi-
tated was filtered and identified as 3a (40 mg). The filtrate was con-
centrated and purified by chromatotron (hexane/EtOAc) to give 1a
(14 mg), an additional amount of 3a (31 mg), and finally 7a (13 mg).
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
12 (21%)
13 (62%)
14 (20%)
15 (21%)
7-(Pyrimidin-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (3a)
Figure 4 3-(6-Azinyl-substituted 2-pyridyl)triazolopyridine 12–15
Yellow solid; yield: 71 mg (21%); mp 168–169 °C (EtOAc).
IR: 3121, 1577, 1460, 1396, 1321, 1202, 1001, 838, 791, 732, 698 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.50 (d, J = 1.3 Hz, 1 H), 9.35 (dd, J = 5.4,
1.4 Hz, 1 H), 9.12 (d, J = 5.4 Hz, 1 H), 8.42 (dd, J = 7.1, 1.2 Hz, 1 H), 8.37
(s, 1 H), 8.05 (dd, J = 8.8, 1.2 Hz, 1 H), 7.59 (dd, J = 8.7, 7.1 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 158.9 (CH), 158.8 (CH), 155.6 (C), 135.3
(C), 134.4 (C), 126.7 (CH), 125.5 (CH), 121.5 (CH), 120.3 (CH), 118.3
(CH).
In conclusion, a series of 7-azinyl-triazolopyridines 3a–
c, 4a–c, 5a–c, and 6a–c were synthesized by addition of
corresponding 7-lithiotriazolopyridine to pyrimidine, pyra-
zine, pyridazine, and 1,3,5-triazine, respectively, followed
by hydrolysis and oxidation. Furthermore, similar reactions
with 7-lithio-3-(2-pyridyl)triazolopyridine gave 3-(6-azi-
nyl-substituted 2-pyridyl)triazolopyridines 12–15. These
new class of polynitrogenated compounds meet the struc-
tural requirements for use in coordination chemistry.
Moreover, based on previous experience with structurally
related derivatives, they are potential leishmanicidal com-
pounds. These promising applications are currently being
studied.
MS: m/z (%) = 170 (12), 143 (69), 116 (100), 102 (2).
HRMS (Q-TOF): m/z [M + H]+ calcd for C10H8N5: 198.0774; found:
198.0770.
7-(Pyrimidin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (7a)
Orange oil; yield: 13 mg (4%).
IR: 3072, 2925, 2855, 2357, 2339, 1564, 1409, 1383, 1352, 1205,
1091, 1029, 789, 729, 701 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.03 (d, J = 4.9 Hz, 2 H), 8.23 (s, 1 H),
7.89 (dd, J = 8.8, 1.25 Hz, 1 H), 7.75 (dd, J = 7.0, 1.3 Hz, 1 H), 7.43 (dd,
J = 4.9, 4.9 Hz, 1 H), 7.39 (dd, J = 8.8, 7.0 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 158.5 (C), 157.8 (CH), 136.5 (C), 126.4
(CH), 125.1 (CH), 120.9 (CH), 120.1 (C), 119.7 (CH), 118.8 (CH).
Melting points were determined on a Büchi B-545. NMR spectra were
recorded on a Bruker AC 300 MHz or 500 MHz in CDCl3 or DMSO-d6 as
solvent; COSY experiments were performed for all compounds. HRMS
(EI) determinations were made using a VG Autospec Trio 1000
(Fisons) and Q-TOF spectrometer 5600 system (Applied Biosystems-
MDS Sciex with ESI+. IR spectra were recorded using FT-IR ATR. All
the lithiation reactions were done under inert atmosphere and dry
solvents.24 All reagents used were from a commercial source (Aldrich).
MS: m/z (%) = 197 (30), 171 (22), 169 (100), 157 (11), 143 (12), 116
(10), 73 (15).
HRMS: m/z [M+] calcd for C10H7N5: 197.0701; found: 197.0689.
3-Methyl-7-(pyrimidin-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (3b),
7,7′-(Pyrimidin-2,4-diyl)bis(3-methyl-[1,2,3]triazolo[1,5-a]pyri-
dine (9), and 3-Methyl-7-(pyrimidin-2-yl)-[1,2,3]triazolo[1,5-
a]pyridine (7b)
[1,2,3]Triazolo[1,5-a]pyridine (1a),25 3-methyl-[1,2,3]triazolo[1,5-
a]pyridine (1b),25 3-phenyl-[1,2,3]triazolo[1,5-a]pyridine (1c),26 and
3-(2-pyridyl)-[1,2,3]triazolo[1,5-a]pyridine (1d)27 were prepared by
literature procedures.
Following the general procedure using 1b (0.2 g), 1.6 M nBuLi (1.3
mL), toluene (75 mL), pyrimidine (0.4 mL), and KMnO4/H2O (0.26 g/50
mL). The crude was purified by chromatotron (hexane/EtOAc) to give
1b (20 mg), then 3b (79 mg), and by increasing the polarity 9 (2 mg),
and finally 7b (47 mg).
Lithiation of [1,2,3]Triazolo[1,5-a]pyridines 1a–d and Reactions
with Azines; General Procedure
To a solution of the corresponding [1,2,3]triazolo[1,5-a]pyridine 1 in
anhydrous toluene at –40 °C under an argon current, a solution of 1.6
nBuLi in hexane (1.1 equiv) was added with stirring; a deep red color
developed. The mixture was kept at –40 °C for 4 h. The azine (1.1
equiv) in dry toluene solution was added and the mixture was kept in
the cold bath at –40 °C for 2 h. The solution was treated with a satu-
rated solution of NH4Cl followed by aq KMnO4 solution for 30 min at
r.t. The mixture was filtered over Celite, the organic and aqueous lay-
ers were separated, the aqueous layer was extracted with CH2Cl2, the
combined organic extracts were dried (Na2SO4), and the solution was
filtered and concentrated to give the crude product.
3-Methyl-7-(pyrimidin-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (3b)
Yellow solid; yield: 79 mg (25%); mp 137–138 °C (EtOAc).
IR: 3314, 3081, 2920, 2853, 1574, 1521, 1463, 1410, 1379, 1335,
1302, 1199, 1121, 1046, 1010, 849, 794, 724, 702, 666 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.33 (d, J = 1.4 Hz, 1 H), 9.20 (dd, J = 5.4,
1.4 Hz, 1 H), 8.96 (dd, J = 5.4, 0.3 Hz, 1 H), 8.23 (dd, J = 7.1, 1.3 Hz, 1 H),
7.78 (dd, J = 8.7, 1.3 Hz, 1 H), 7.35 (dd, J = 8.8, 7.1 Hz, 1 H), 2.67 (s, 3
H).
13C NMR (75 MHz, CDCl3): δ = 158.7 (CH), 158.7 (CH), 155.6 (C), 135.4
(C), 133.9 (C), 133.1 (C), 123.8 (CH), 121.3 (CH), 119.8 (CH), 118.1
(CH), 10.5 (CH3).
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Synthesis
MS: m/z (%) = 212 (12), 184 (100), 167 (8), 157 (17), 142 (8), 131 (55),
3-Phenyl-7-(pyrimidin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (7c)
104 (10).
Yellow solid; yield: 11 mg (4%); mp 158–159 °C (EtOAc).
IR: 3049, 2933, 2845, 1566, 1411, 1401, 1122, 1011, 784, 735 cm–1
HRMS (Q-TOF): m/z [M + H]+ calcd for C11H10N5: 212.0931; found:
212.0926.
.
1H NMR (300 MHz, CDCl3): δ = 9.04 (d, J = 4.9 Hz, 2 H), 8.15 (dd, J = 8.9,
1.2 Hz, 1 H), 8.02–7.95 (m, 2 H), 7.72 (dd, J = 6.9, 1.2 Hz, 1 H), 7.58–
7.50 (m, 2 H), 7.49–7.40 (m, 3 H).
13C NMR (75 MHz, CDCl3): δ = 160.2 (C), 157.8 (CH), 138.6 (C), 135.7
(C), 131.9 (C), 131.5 (C), 129.1 (CH), 128.1 (CH), 127.2 (CH), 125.5
(CH), 121.0 (CH), 120.0 (CH), 118.8 (CH).
7,7′-(Pyrimidin-2,4-diyl)bis(3-methyl-[1,2,3]triazolo[1,5-a]pyri-
dine (9)
White solid; yield: 2 mg (3%); mp 215–216 °C (EtOAc).
IR: 3023, 2357, 2328, 1569, 1468, 1424, 1380, 1293, 1163, 1091,
1050, 988, 853, 799, 758, 707 cm–1
.
MS: m/z (%) = 273 (3), 245 (100), 192 (27), 164 (6), 122 (2), 63 (2).
HRMS: m/z [M+] calcd for C16H11N5: 273.1014; found: 273.1002.
1H NMR (300 MHz, CDCl3): δ = 9.36 (d, J = 5.3 Hz, 1 H), 9.21 (d, J = 5.3
Hz, 1 H), 8.68 (dd, J = 7.1, 1.3 Hz, 1 H), 7.93 (dd, J = 6.9, 1.3 Hz, 1 H),
7.84 (dd, J = 8.7, 1.3 Hz, 1 H), 7.82 (dd, J = 8.8, 1.3 Hz, 1 H), 7.45 (dd, J =
8.8, 7.1 Hz, 1 H), 7.37 (dd, J = 8.8, 6.9 Hz, 1 H), 2.73 (s, 3 H), 2.72 (s, 3
H).
13C NMR (75 MHz, CDCl3): δ = 159.7 (CH), 159.6 (C), 156.2 (C), 147.2
(C), 145.6 (C), 140.7 (C), 138.5 (C), 135.1 (C), 133.3 (C), 124.3 (CH),
123.6 (CH), 120.3 (CH), 120.2 (CH), 119.6 (CH), 119.6 (CH), 118.9 (CH),
10.67 (CH3), 10.63 (CH3).
3-[6-(Pyrimidin-4-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-a]pyridine
(12) and 3-[6-(Pyrimidin-2-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-
a]pyridine (16)
Following the general procedure using 1d (0.2 g), 1.6 M nBuLi (0.9
mL), toluene (50 mL), pyrimidine (0.2 mL), and KMnO4/H2O (0.17 g/40
mL). The crude was treated with EtOAc, the yellow solid that precipi-
tated was filtered and identified as 12 (21 mg). The filtrate was puri-
fied by chromatotron (hexane/EtOAc) to give 1d (25 mg), an addition-
al amount of 12 (37 mg), then 16 (3 mg).
HRMS (Q-TOF): m/z [M + H]+ calcd for C18H15N8: 343.1420; found:
343.1429.
3-Methyl-7-(pyrimidin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (7b)
3-[6-(Pyrimidin-4-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-a]pyridine
Orange solid; yield: 47 mg (15%); mp 165–166 °C (EtOAc).
(12)
1H NMR (300 MHz, CDCl3): δ = 9.02 (d, J = 4.9 Hz, 2 H), 7.77 (dd, J = 8.8,
1.2 Hz, 1 H), 7.71 (dd, J = 6.9, 1.2 Hz, 1 H), 7.42 (dd, J = 4.9, 4.9 Hz, 1 H),
7.32 (dd, J = 8.8, 6.9 Hz, 1 H), 2.69 (s, 3 H).
Yellow solid; yield: 58 mg (21%); mp 254–255 °C (EtOAc).
IR: 3089, 2925, 2856, 1576, 1524, 1415, 1385, 1313, 1202, 1116,
1007, 844, 794, 727, 696 cm–1
.
13C NMR (75 MHz, CDCl3): δ = 160.2 (C), 157.7 (CH), 135.5 (C), 135.0
(C), 133.1 (C), 123.6 (CH), 120.8 (CH), 119.3 (CH), 118.7 (CH), 10.6
(CH3).
1H NMR (300 MHz, DMSO-d6): δ = 9.37 (d, J = 1.3 Hz, 1 H), 9.23 (d, J =
7.0 Hz, 1 H), 9.07 (d, J = 5.3 Hz, 1 H), 8.79 (d, J = 8.9 Hz, 1 H), 8.56 (dd,
J = 5.2, 1.4 Hz, 1 H), 8.47–8.41 (m, 2 H), 8.18 (dd, J = 7.9, 7.9 Hz, 2 H),
7.71 (ddd, J = 8.9, 6.7, 0.9 Hz, 1 H), 7.37 (ddd, J = 6.9, 6.9, 1.2 Hz, 1 H).
MS: m/z (%) = 211 (20), 183 (88), 182 (100), 157 (60), 149 (17), 129
13C NMR (75 MHz, CDCl3): δ = 158.9 (CH), 158.7 (CH), 152.1 (CH),
149.6 (C), 141.6 (C), 138.9 (CH), 128.5 (CH), 126.3 (C), 125.0 (C), 121.9
(CH), 120.9 (C), 119.9 (CH), 119.8 (CH), 117.4 (CH), 116.9 (CH).
(26), 104 (37), 79 (20), 57 (18).
HRMS: m/z [M+] calcd for C11H9N5: 211.0858; found: 211.0852.
3-Phenyl-7-(pyrimidin-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (3c)
and 3-Phenyl-7-(pyrimidin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine
(7c)
MS: m/z (%) = 247 (100), 230 (4), 220 (12), 194 (53), 167 (7).
HRMS (Q-TOF): m/z [M + H]+ calcd for C16H12N5: 275.1040; found:
275.1043.
Following the general procedure using 1c (0.2 g), 1.6 M nBuLi (0.9
mL), toluene (50 mL), pyrimidine (0.2 mL), and KMnO4/H2O (0.17 g/40
mL). The crude was purified by chromatotron (hexane/EtOAc) to give
1c (120 mg), 3c (42 mg), and finally 7c (11 mg).
3-[6-(Pyrimidin-2-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-a]pyridine
(16)
Yellow solid; yield: 3 mg (1%); mp 173–174 °C (EtOAc).
IR: 3077, 2922, 2858, 2364, 2331, 1561, 1525, 1429, 1386, 1313,
3-Phenyl-7-(pyrimidin-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (3c)
Yellow solid; yield: 42 mg (15%); mp 166–167 °C (EtOAc).
1241, 1122, 1094, 1021, 990, 815, 735, 698 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.10 (ddd ap., J = 8.9, 1.2, 1.2 Hz, 1 H),
8.97 (d, J = 4.8 Hz, 2 H), 8.77 (ddd ap., J = 7.0, 1.0, 1.0 Hz, 1 H), 8.47 (dd,
J = 7.9, 1.0 Hz, 1 H), 8.40 (dd, J = 7.8, 1.0 Hz, 1 H), 7.98 (dd, J = 7.8, 7.8
Hz, 1 H), 7.46 (ddd, J = 8.9, 6.7, 1.0 Hz, 1 H), 7.35 (dd, J = 4.8, 4.8 Hz, 1
H), 7.07 (ddd, J = 6.9, 6.9, 1.3 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 164.2 (C), 157.8 (CH), 154.5 (C), 152.3
(C), 143.5 (C), 137.9 (CH), 132.7 (C), 127.0 (CH), 125.3 (CH), 122.1
(CH), 122.0 (CH), 121.7 (CH), 120.5 (CH), 116.3 (CH).
IR: 3472, 3406, 3084, 2917, 2848, 1565, 1465, 1385, 1257, 1129,
1071, 1008, 855, 805, 733, 696, 663 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.40 (d, J = 1.3 Hz, 1 H), 9.25 (dd, J = 5.4,
1.4 Hz, 1 H), 9.02 (dd, J = 5.3, 0.3 Hz, 1 H), 8.32 (dd, J = 7.1, 1.2 Hz, 1 H),
8.19 (dd, J = 8.9, 1.2 Hz, 1 H), 8.00–7.97 (m, 2 H), 7.58–7.41 (m, 4 H).
13C NMR (75 MHz, CDCl3): δ = 158.9 (CH), 158.8 (CH), 157.8 (C), 155.6
(C), 139.0 (C), 134.6 (C), 131.2 (C), 129.3 (CH), 128.5 (CH), 127.3 (CH),
125.8 (CH), 121.6 (CH), 120.7 (CH), 118.5 (CH).
MS: m/z (%) = 274 (15), 246 (100), 193 (26), 169 (5), 156 (4), 142 (3),
MS: m/z (%) = 274 (8), 245 (50), 219 (16), 193 (19), 167 (100).
123 (3), 78 (10).
HRMS (Q-TOF): m/z [M + H]+ calcd for C16H12N5: 274.1087; found:
HRMS: m/z [M+] calcd for C15H10N6: 274.0967; found: 274.0965.
274.1088.
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Synthesis
7-(Pyrazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (4a)
MS: m/z (%) = 245 (54), 218 (13), 191 (13), 167 (100), 139 (3).
HRMS (Q-TOF): m/z [M + H]+ calcd for C16H12N5: 274.1087; found:
274.1086.
Following the general procedure using 1a (0.5 g), 1.6 M nBuLi (3.6
mL), toluene (50 mL), pyrazine/toluene (1 g/5 mL), and KMnO4/H2O
(0.66 g/50 mL). The crude was treated with EtOAc, the yellow solid
that precipitated was filtered and identified as 4a (129 mg). The fil-
trate was purified by chromatotron (hexane/EtOAc) to give 1a (42 mg)
and an additional amount of 4a (21 mg); yellow solid; yield: 150 mg
(17%); mp 209–210 °C (EtOAc).
3-[6-(Pyrazin-2-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-a]pyridine
(13)
Following the general procedure using 1d (0.5 g), 1.6 M nBuLi (2.2
mL), toluene (50 mL), pyrazine/toluene (0.62 g/5 mL), and KMnO4/H2O
(0.40 g/50 mL). The crude was treated with EtOAc, the yellow solid
that precipitated was filtered and identified as 13 (283 mg). The fil-
trate was purified by chromatotron (hexane/EtOAc) to give 1d (63
mg) and an additional amount of 13 (136 mg); yellow solid; yield: 419
mg (62%); mp 218–219 °C (EtOAc).
IR: 3850, 3733, 3645, 3563, 2153, 1507, 1453, 1101, 1019 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 10.28 (d, J = 1.5 Hz, 1 H), 8.80–8.70 (m,
2 H), 8.25 (s, 1 H), 7.98 (dd, J = 7.1, 1.2 Hz, 1 H), 7.89 (dd, J = 8.8, 1.2
Hz, 1 H), 7.46 (dd, J = 8.8, 7.1 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 146.2 (CH), 145.4 (C), 145.3 (CH), 144.4
(CH), 135.1 (C), 134.4 (C), 126.5 (CH), 125.6 (CH), 119.1 (CH), 117.6
(CH).
IR: 3085, 2920, 2842, 2359, 1525, 1380, 1114, 1089, 1032, 804, 737
cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.78 (d, J = 1.3 Hz, 1 H), 8.83–8.80 (m, 2
H), 8.70–8.61 (m, 2 H), 8.48 (dd, J = 7.9, 0.9 Hz, 1 H), 8.33 (d, J = 7.8, 0.9
Hz, 1 H), 7.98 (dd, J = 7.9, 7.9 Hz, 1 H), 7.48 (dd, J = 9.2, 6.8 Hz, 1 H),
7.11 (ddd, J = 6.8, 6.8, 1.2 Hz, 1 H).
MS: m/z (%) = 198 (3), 170 (5), 143 (72), 116 (100), 102 (7).
HRMS (Q-TOF): m/z [M + H]+ calcd for C10H8N5: 198.0774; found:
198.0774.
13C NMR (75 MHz, CDCl3): δ = 153.8 (C), 152.0 (C), 151.6 (C), 144.6
(CH), 144.0 (CH), 143.3 (CH), 138.1 (CH), 137.2 (C), 132.2 (C), 127.0
(CH), 125.6 (CH), 121.5 (CH), 121.1 (CH), 120.0 (CH), 116.2 (CH).
3-Methyl-7-(pyrazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (4b)
Following the general procedure using 1b (0.3 g), 1.6 M nBuLi (1.9
mL), toluene (165 mL), pyrazine/toluene (0.55 g/5 mL), and
KMnO4/H2O (0.39 g/100 mL). The crude was treated with EtOAc, the
yellow solid that precipitated was filtered and identified as 4b (45
mg). The filtrate was purified by chromatotron (hexane/EtOAc) to give
1b (84 mg) and an additional amount of 4b (98 mg); yellow solid;
yield: 143 mg (30%); mp 136–137 °C (EtOAc).
MS: m/z (%) = 247 (100), 220 (22), 193 (5), 168 (5).
HRMS (Q-TOF): m/z [M + H]+ calcd for C15H11N6: 274.1087; found:
275.1037.
7-(Pyridazin-3-yl)-[1,2,3]triazolo[1,5-a]pyridine (5a) and 7-(Pyri-
dazine-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (8a)
IR: 3078, 3050, 2917, 1526, 1463, 1413, 1382, 1321, 1216, 1121,
1043, 1013, 849, 788, 724, 674 cm–1
.
Following the general procedure using 1a (0.5 g), 1.6 M nBuLi (3.6
mL), toluene (50 mL), pyridazine/toluene (1 g/5 mL), and KMnO4/H2O
(0.66 g/50 mL). The crude was treated with EtOAc, the yellow solid
that precipitated was filtered and identified as 5a (64 mg). The filtrate
was purified by chromatotron (hexane/EtOAc) to give 1a (76 mg) and
an additional amount of 5a (25 mg), and finally 8a (14 mg).
1H NMR (300 MHz, CDCl3): δ = 10.30 (d, J = 1.5 Hz, 1 H), 8.78–8.68 (m,
2 H), 7.95 (dd, J = 7.0, 1.2 Hz, 1 H), 7.77 (dd, J = 8.8, 1.2 Hz, 1 H), 7.38
(dd, J = 8.8, 7.1 Hz, 1 H), 2.71 (s, 3 H).
13C NMR (75 MHz, CDCl3): δ = 146.1 (CH), 145.5 (C), 145.2 (CH), 144.4
(CH), 133.1 (C), 129.6 (C), 124.1 (CH), 123.7 (C), 118.7 (CH), 117.4
(CH), 10.65 (CH3).
7-(Pyridazin-3-yl)-[1,2,3]triazolo[1,5-a]pyridine (5a)
MS: m/z (%) = 212 (10), 184 (100), 156 (72), 142 (10), 129 (53), 104
(35).
HRMS (Q-TOF): m/z [M + H]+ calcd for C11H10N5: 212.0931; found:
Yellow solid; yield: 89 mg (14%); mp 179–180 °C (EtOAc).
IR: 3139, 1546, 1456, 1318, 1207, 1089, 1039, 949, 853, 779, 722 cm–1
.
212.0927.
1H NMR (300 MHz, CDCl3): δ = 9.30 (dd, J = 5.0, 1.6 Hz, 1 H), 9.21 (dd,
J = 8.8, 1.6 Hz, 1 H), 8.25 (s, 1 H), 8.20 (dd, J = 7.1, 1.2 Hz, 1 H), 7.93
(dd, J = 8.8, 1.2 Hz, 1 H), 7.72 (dd, J = 8.8, 5.0 Hz, 1 H), 7.50 (dd, J = 8.8,
7.1 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 153.5 (C), 151.3 (CH), 135.1 (C), 134.1
(C), 128.2 (CH), 126.6 (CH), 126.4 (CH), 125.8 (CH), 119.4 (CH), 117.6
(CH).
3-Phenyl-7-(pyrazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (4c)21
Following the general procedure using 1c (0.5 g), 1.6 M nBuLi (2.2
mL), toluene (50 mL), pyrazine/toluene (0.62 g/5 mL), and KMnO4/H2O
(0.40 g/50 mL). The crude was treated with EtOAc, the yellow solid
that precipitated was filtered and identified as 4c (66 mg). The filtrate
was purified by chromatotron (hexane/EtOAc) to give 1c (71 mg) and
an additional amount of 4c (360 mg); yellow solid; yield: 426 mg
(61%); mp 141–142 °C (EtOAc). The structure of this compound was
confirmed by powder X-diffraction data.
MS: m/z (%) = 170 (17), 153 (3), 143 (37), 129 (4), 116 (100), 102 (8).
HRMS (Q-TOF): m/z [M + H]+ calcd for C10H8N5: 198.0774; found:
198.0770.
IR: 3108, 3031, 1540, 1458, 1394, 1264, 1127, 1058, 998, 918, 853,
7-(Pyridazine-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (8a)
722, 689 cm–1
.
Orange solid; yield: 14 mg (2%); mp 333–334 °C (EtOAc).
IR: 3142, 1548, 1373, 1308, 1197, 1091, 1052, 998, 970, 828, 742 cm–1
1H NMR (300 MHz, CDCl3): δ = 9.75 (dd, J = 2.4, 1.2 Hz, 1 H), 9.44 (dd,
J = 5.5, 1.2 Hz, 1 H), 8.53 (dd, J = 5.5, 2.5 Hz, 1 H), 8.25 (s, 1 H), 7.91
(dd, J = 8.8, 1.2 Hz, 1 H), 7.44 (dd, J = 8.8, 7.0 Hz, 1 H), 7.35 (dd, J = 7.0,
1.3 Hz, 1 H).
1H NMR (300 MHz, CDCl3): δ = 10.32 (d, J = 0.9 Hz, 1 H), 8.78–8.72 (m,
2 H), 8.15 (dd, J = 8.8, 0.9 Hz, 1 H), 8.02–7.99 (m, 3 H), 7.58–7.43 (m, 4
H).
13C NMR (75 MHz, CDCl3): δ = 146.3 (CH), 145.4 (C), 145.3 (CH), 144.5
(CH), 138.8 (C), 134.6 (C), 131.9 (C), 131.3 (C), 129.2 (CH), 128.4 (CH),
127.2 (CH), 126.0 (CH), 119.5 (CH), 117.8 (CH).
.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2017, 49, A–H

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Synthesis
13C NMR (75 MHz, CDCl3): δ = 151.6 (CH), 151.5 (C), 149.6 (CH), 133.6
(C), 130.4 (C), 127.0 (CH), 125.6 (CH), 125.4 (CH), 119.8 (CH), 116.8
(CH).
13C NMR (75 MHz, CDCl3): δ = 153.5 (C), 151.3 (CH), 138.9 (C), 134.3
(C), 131.9 (C), 131.3 (C), 129.3 (CH), 128.4 (CH), 128.3 (CH), 127.2
(CH), 126.4 (CH), 126.2 (CH), 119.9 (CH), 117.8 (CH).
MS: m/z (%) = 169 (5), 153 (5), 142 (20), 116 (100).
MS: m/z (%) = 245 (41), 229 (25), 219 (48), 205 (19), 191 (100), 167
(98), 139 (38).
HRMS (Q-TOF): m/z [M+ + H – N2] calcd for C10H8N3: 170.0713; found:
170.0710.
HRMS (Q-TOF): m/z [M + H]+ calcd for C16H12N5: 274.1087; found:
274.1088.
3-Methyl-7-(pyridazin-3-yl)-[1,2,3]triazolo[1,5-a]pyridine (5b)
and 3-Methyl-7-(pyridazine-4-yl)-[1,2,3]triazolo[1,5-a]pyridine
(8b)
3-[6-(Pyridazin-3-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-a]pyridine
(14)21
Following the general procedure using 1b (0.5 g), 1.6 M nBuLi (3.2
mL), toluene (50 mL), pyridazine/toluene (0. 90 g/5 mL), and
KMnO4/H2O (0.59 g/50 mL). The crude was purified by chromatotron
(hexane/EtOAc) to give 1b (43 mg), 5b (167 mg), and finally 8b (34
mg).
Following the general procedure using 1d (0.5 g), 1.3 M nBuLi (2.2
mL), toluene (50 mL), pyridazine/toluene (0.62 g/5 mL), and KMnO4/
H2O (0.40 g/50 mL). The crude was purified by chromatotron (hex-
ane/EtOAc) to give 1d (108 mg) and then 14 as a yellow solid; yield:
140 mg (20%); mp 232–233 °C (EtOAc). The structure of this com-
pound was confirmed by powder X-diffraction data.
IR: 3086, 3025, 1529, 1438, 1402, 1368, 1113, 1035, 741, 691 cm–1
.
3-Methyl-7-(pyridazin-3-yl)-[1,2,3]triazolo[1,5-a]pyridine (5b)
Yellow solid; yield: 167 mg (21%); mp 191–192 °C (EtOAc).
1H NMR (300 MHz, CDCl3): δ = 9.26 (dd, J = 4.9, 1.7 Hz, 1 H), 8.81 (ddd,
J = 7.0, 1.0, 1.0 Hz, 1 H), 8.69 (ddd, J = 8.9, 1.2, 1.2 Hz, 1 H), 8.63 (dd, J =
7.8, 1.0 Hz, 1 H), 8.60 (dd, J = 8.5, 1.7 Hz, 1 H), 8.49 (dd, J = 7.9, 1.0 Hz,
1 H), 8.01 (dd, J = 7.9, 7.9 Hz, 1 H), 7.69 (dd, J = 8.6, 4.9 Hz, 1 H), 7.45
(ddd, J = 8.9, 6.7, 1.0 Hz, 1 H), 7.10 (ddd, J = 6.9, 6.9, 1.3 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 159.0 (C), 153.2 (C), 152.0 (C), 151.3
(CH), 138.2 (CH), 137.3 (C), 132.1 (C), 127.2 (CH), 126.8 (CH), 125.7
(CH), 124.4 (CH), 121.9 (CH), 120.8 (CH), 120.3 (CH), 116.0 (CH).
IR: 3077, 2953, 2917, 2847, 2353, 1566, 1530, 1373, 1246, 1197,
1163, 1096, 1032, 812, 737, 693 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.26 (dd, J = 5.0, 1.6 Hz, 1 H), 9.18 (dd,
J = 8.8, 1.6 Hz, 1 H), 8.13 (dd, J = 7.0, 1.1 Hz, 1 H), 7.78 (dd, J = 8.8, 1.2
Hz, 1 H), 7.69 (dd, J = 8.8, 5.0 Hz, 1 H), 7.39 (dd, J = 8.8, 7.1 Hz, 1 H),
2.69 (s, 3 H).
13C NMR (75 MHz, CDCl3): δ = 153.5 (C), 151.2 (CH), 135.4 (C), 133.7
(C), 133.0 (C), 128.0 (CH), 126.4 (CH), 124.3 (CH), 119.0 (CH), 117.4
(CH), 10.6 (CH3).
MS: m/z (%) = 247 (100), 230 (5), 220 (22), 193 (55), 167 (56), 140 (9).
HRMS (Q-TOF): m/z [M + H]+ calcd for C15H11N6: 275.1040; found:
275.1037.
MS: m/z (%) = 212 (4), 184 (100), 157 (4), 130 (42), 104 (10).
HRMS (Q-TOF): m/z [M + H]+ calcd for C11H10N5: 212.0931; found:
212.0938.
7-(1,3,5-Triazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (6a) and
[1,2,3]Triazolo[1,5-a]pyridine-7-carboxamide (10)
Following the general procedure using 1a (0.5 g), 1.3 M nBuLi (2.9
mL), toluene (50 mL), 1,3,5-triazine/toluene (1.02 g/5 mL), and
KMnO4/H2O (0.66 g/50 mL). The crude was treated with EtOAc, the
yellow solid that precipitated was filtered and identified as 6a (36
mg). The filtrate was purified by chromatotron (hexane/EtOAc) to give
1a (175 mg), then traces of 10 (9 mg), and finally an additional
amount of 6a (47 mg).
3-Methyl-7-(pyridazine-4-yl)-[1,2,3]triazolo[1,5-a]pyridine (8b)
Oil; yield: 34 mg (4%).
IR: 3442, 3374, 3250, 2927, 2865, 2362, 2334, 1540, 1450, 1429,
1360, 1254, 1215, 1135, 905, 784, 727 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.74 (dd, J = 2.3, 1.1 Hz, 1 H), 9.41 (dd,
J = 5.5, 1.1 Hz, 1 H), 8.54 (dd, J = 5.5, 2.4 Hz, 1 H), 7.78 (dd, J = 8.3, 1.7
Hz, 1 H), 7.39–7.29 (m, 2 H), 2.69 (s, 3 H).
13C NMR (75 MHz, CDCl3): δ = 151.6 (CH), 149.5 (CH), 135.9 (C), 132.8
(C), 132.2 (C), 130.5 (C), 125.5 (CH), 123.8 (CH), 119.4 (CH), 116.7
(CH), 10.6 (CH3).
7-(1,3,5-Triazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (6a)
Yellow solid; yield: 83 mg (10%); mp 183–185 °C (EtOAc).
IR: 1683, 1628, 1559, 1507, 1450, 1411, 1365, 1019, 740 cm–1
.
MS: m/z (%) = 184 (58), 167 (53), 157 (100), 144 (63), 130 (38), 117
(5), 104 (7).
HRMS (Q-TOF): m/z [M + H]+ calcd for C11H10N5: 212.0931; found:
1H NMR (300 MHz, CDCl3): δ = 9.49 (s, 2 H), 8.29 (s, 1 H), 8.12 (dd, J =
7.0, 1.3 Hz, 1 H), 8.01 (dd, J = 8.8, 1.3 Hz, 1 H), 7.44 (dd, J = 8.8, 7.0 Hz,
1 H).
212.0938.
13C NMR (75 MHz, CDCl3): δ = 166.9 (CH), 150.7 (C), 140.9 (C), 131.9
(C), 127.0 (CH), 124.8 (CH), 122.1 (CH), 121.2 (CH).
3-Phenyl-7-(pyridazin-3-yl)-[1,2,3]triazolo[1,5-a]pyridine (5c)
MS: m/z (%) = 199 (11), 171 (2), 144 (100), 117 (13).
Following the general procedure using 1c (0.5 g), 1.6 M nBuLi (2.2
mL), toluene (50 mL), pyridazine/toluene (0.90 g/5 mL), and
KMnO4/H2O (0.40 g/50 mL). The crude was purified by chromatotron
(hexane/EtOAc) to give 1c (202 mg) and then 5c as an orange solid;
yield: 77 mg (11%); mp 191–192 °C (EtOAc).
HRMS (Q-TOF): m/z [M + H]+ calcd for C9H7N4: 199.0727; found:
199.0726.
[1,2,3]Triazolo[1,5-a]pyridine-7-carboxamide (10)
Oil; yield: 9 mg (1%).
IR: 3095, 2158, 1571, 1442, 1417, 1269, 1225, 1140, 1065, 1001, 851,
786, 735, 696 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.80 (sa, 2 H), 8.25 (s, 1 H), 8.15 (dd, J =
7.0, 1.3 Hz, 1 H), 7.98 (dd, J = 8.8, 1.3 Hz, 1 H), 7.46 (dd, J = 8.8, 7.0 Hz,
1 H).
1H NMR (300 MHz, CDCl3): δ = 9.30 (dd, J = 5.0, 1.6 Hz, 1 H), 9.22 (dd,
J = 8.8, 1.6 Hz, 1 H), 8.23–8.15 (m, 2 H), 8.03–7.96 (m, 2 H), 7.73 (dd,
J = 8.8, 5.0 Hz, 1 H), 7.59–7.50 (m, 3 H), 7.47–7.40 (m, 1 H).
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2017, 49, A–H

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Synthesis
13C NMR (75 MHz, CDCl3): δ = 166.6 (C=O), 129.9 (C), 129.5 (C), 126.9
(CH), 125.6 (CH), 121.6 (CH), 121.2 (CH).
1H NMR (300 MHz, CDCl3): δ = 9.42 (s, 2 H), 9.09 (ddd, J = 8.9, 1.2, 1.2
Hz, 1 H), 8.80 (ddd, J = 7.0, 1.1, 1.1 Hz, 1 H), 8.56 (dd, J = 8.0, 1.0 Hz, 1
H), 8.51 (dd, J = 7.8, 1.0 Hz, 1 H), 8.03 (dd, J = 7.9, 7.9 Hz, 1 H), 7.51
(ddd, J = 8.9, 6.7, 1.0 Hz, 1 H), 7.11 (ddd, J = 6.9, 6.7, 1.2 Hz, 1 H).
13C NMR (75 MHz, CDCl3): δ = 170.6 (C), 167.0 (CH), 152.9 (C), 152.1
(C), 138.1 (CH), 137.1 (C), 132.8 (C), 127.4 (CH), 125.4 (CH), 123.4
(CH), 123.0 (CH), 121.8 (CH), 116.3 (CH).
MS: m/z (%) = 163 (18), 120 (15), 107 (100).
HRMS (Q-TOF): m/z [M + H]+ calcd for C7H7N4: 163.0614; found:
163.0612.
3-Methyl-7-(1,3,5-triazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (6b)
MS: m/z (%) = 248 (20), 194 (100), 167 (32).
HRMS (Q-TOF): m/z [M + H]+ calcd for C14H10N7: 276.0992; found:
276.0997.
Following the general procedure using 1b (0.5 g), 1.3 M nBuLi (2.6
mL), toluene (50 mL), 1,3,5-triazine/toluene (0.91 g/5 mL), and
KMnO4/H2O (0.59 g/50 mL). The crude was treated with EtOAc, the
yellow solid that precipitated was filtered and identified as 6b (145
mg). The filtrate was purified by chromatotron (hexane/EtOAc) to give
1b (43 mg) and an additional amount of 6b (189 mg); yellow solid;
yield: 334 mg (42%); mp 161–163 °C (EtOAc).
Funding Information
We are very grateful to University of Valencia (Spain) (UV-INV-AE 15-
IR: 3308, 3153, 3031, 2923, 1546, 1518, 1421, 1390, 1343, 1318,
332846) for its financial support.
Unveiytrsi
of
Vaelnaci
U(V
N
-IV-A
E
1
5-3
3
2
8
4
6)
1221, 1202, 1105, 1146, 985, 952, 824, 780, 735, 721, 691 cm–1
.
1H NMR (300 MHz, CDCl3): δ = 9.47 (s, 2 H), 8.09 (dd, J = 7.0, 1.3 Hz, 1
H), 7.88 (dd, J = 8.8, 1.3 Hz, 1 H), 7.36 (dd, J = 8.8, 7.0 Hz, 1 H), 2.71 (s,
3 H).
Acknowledgment
13C NMR (75 MHz, CDCl3): δ = 166.8 (CH), 135.8 (C), 133.3 (C), 132.8
(C), 123.2 (CH), 121.7 (CH), 121.3 (CH), 10.6 (CH3).
We would like to thank the SCSIE of the University of Valencia for re-
cording the MS data.
MS: m/z (%) = 131 (71), 104 (100), 103 (6).
HRMS (Q-TOF): m/z [M + H]+ calcd for C10H9N6: 213.0810; found:
213.0883.
Supporting Information
Supporting information for this article is available online at
https://doi.org/10.1055/s-0036-1588525.
S
u
p
p
o
nrtogI
f
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p
p
ortiInfogrmoaitn
3-Phenyl-7-(1,3,5-triazin-2-yl)-[1,2,3]triazolo[1,5-a]pyridine (6c)
Following the general procedure using 1c (0.5 g), 1.3 M nBuLi (1.8
mL), toluene (50 mL), 1,3,5-triazine/toluene (0.62 g/5 mL), and
KMnO4/H2O (0.40 g/50 mL). The crude was treated with EtOAc, the
yellow solid that precipitated was filtered and identified as 6c (46
mg). The filtrate was purified by chromatotron (hexane/EtOAc) to give
1c (63 mg) and an additional amount of 6c (101 mg); yellow solid;
yield: 147 mg (21%); mp 174–175 °C (EtOAc).
References
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IR: 3039, 1546, 1448, 1422, 1386, 1362, 1220, 1150, 1014, 776, 740,
707 cm–1
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1H NMR (300 MHz, CDCl3): δ = 9.49 (s, 2 H), 8.25 (dd, J = 8.9, 1.2 Hz, 1
H), 8.07 (dd, J = 7.0, 1.2 Hz, 1 H), 8.01–7.97 (m, 2 H), 7.58–7.41 (m, 4
H).
13C NMR (75 MHz, CDCl3): δ = 166.9 (CH), 152.5 (C), 145.2 (C), 132.1
(C), 131.2 (C), 129.3 (CH), 128.5 (CH), 127.4 (CH), 125.0 (CH), 122.4
(CH), 121.2 (CH).
MS: m/z (%) = 275 (7), 247 (13), 220 (4), 193 (100), 166 (32), 139 (5).
HRMS (Q-TOF): m/z [M + H]+ calcd for C15H11N6: 275.1040; found:
275.0978.
3-[6-(1,3,5-Triazin-2-yl)pyridin-2-yl]-[1,2,3]triazolo[1,5-a]pyri-
dine (15)
Following the general procedure using 1d (0.5 g), 1.3 M nBuLi (1.8
mL), toluene (50 mL), 1,3,5-triazine/toluene (0.62 g/5 mL), and
KMnO4/H2O (0.40 g/50 mL). The crude was treated with EtOAc, the
yellow solid that precipitated was filtered and identified as 15 (90
mg). The filtrated was purified by chromatotron (hexane/EtOAc) to
give 1d (74 mg) and then an additional amount of 15 (73 mg); yellow
solid; yield: 163 mg (21%); mp 252–253 °C (EtOAc).
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IR: 3124, 3039, 1553, 1535, 1453, 1435, 1414, 1386, 1334, 1262,
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1194, 1174, 1117, 1037, 985, 804, 753, 688 cm–1
.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2017, 49, A–H

H
R. Adam et al.
Paper
Synthesis
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