Unusual heterocyclization of chalcone podands with 3-amino-1,2,4-triazole

Article abstract of DOI:10.1007/s11172-011-0152-5

A new type of intramolecular cyclization of 1,5-bis[2-(E-3-oxo-3- phenylprop-1-enyl)-phenoxy]-3-oxapentane with 3-aminotriazole promoted by potassium ions was discovered. A cascade mechanism for the formation of crownophane with 4,7-dihydro[1,2,4]triazolo

Full text of DOI:10.1007/s11172-011-0152-5

Russian Chemical Bulletin, International Edition, Vol. 60, No. 5, pp. 965—974, May, 2011
965
Unusual heterocyclization of chalcone podands with 3ꢀaminoꢀ1,2,4ꢀtriazole
I. G. Ovchinnikova, M. S. Valova, E. G. Matochkina, M. I. Kodess, A. A. Tumashov,
P. A. Slepukhin, O. V. Fedorova, G. L. Rusinov, and V. N. Charushin
I. Ya. Postovsky Institute of Organic Synthesis, Ural Branch of the Russian Academy of Sciences,
22/20 ul. S. Kovalevskoi, 620041 Ekaterinburg, Russian Federation.
Fax: +7 (343) 374 1189. Eꢀmail: iov@ios.uran.ru
A new type of intramolecular cyclization of 1,5ꢀbis[2ꢀ(Eꢀ3ꢀoxoꢀ3ꢀphenylpropꢀ1ꢀenyl)ꢀ
phenoxy]ꢀ3ꢀoxapentane with 3ꢀaminotriazole promoted by potassium ions was discovered.
A cascade mechanism for the formation of crownophane with 4,7ꢀdihydro[1,2,4]triazolo[1,5ꢀa]ꢀ
pyrimidine fragment was suggested. Effects of oligooxyethylene fragment of the chalcone podand
and acidꢀbase catalysis on the selectivity of the cyclocondensation processes and degree of
oxidation of triazolopyrimidine fragments were studied. The product structures were confirmed
by IR, 1H and 13C NMR spectroscopy and Xꢀray diffraction study.
Key words: template synthesis, chalcone podand, crown ethers, cascade reaction, heteroꢀ
cyclization, 1,2,4ꢀtriazolo[1,5ꢀa]pyrimidineꢀcontaining podands.
Azolopyrimidines with the nodal nitrogen atom, inꢀ
cluding 1,2,4ꢀtriazolo[1,5ꢀa]pyrimidines and their dihydro
derivatives, synthetic analogs of purines and nucleosides,
exhibit a wide range of biological activity.1—7 In addition,
these compounds tend to form fairly stable complexes with
metal ions.8—12
Incorporation of an oligooxyethylene fragment into
azolopyrimidines and preparation of the openꢀchain anaꢀ
logs of crown ethers (podands) can be of certain interest
for medicinal chemistry, since it is known that podands
can mimic behavior of natural ionophores (for example,
nihericine), performing transportation function in livꢀ
ing cells.13
into the threeꢀcomponent Biginelly reaction with aminoꢀ
azoles and ethyl acetoacetate to form expected bisꢀdiꢀ
hydroazolopyrimidine derivatives.26 At the same time, atꢀ
tempted preparation of analogous bisꢀ1,4ꢀdihydropyridine
polyether systems in the Ganch reaction led to γꢀpiperiꢀ
doneꢀcontaining crownophanes.27,28 Unusual ability to be
converted to macrocyclic structures as a result of photoꢀ
chemical transformations or reactions with binucleophiles
was found for chalcone podands as well.25,29
In the present work, we studied reactions of the earlier
synthesized chalcone podand 1 with 3ꢀaminoꢀ1,2,4ꢀtriꢀ
azole and considered effect of the acidꢀbase catalysis and
solvent on the selectivity of chemical transformations.
One of the most convenient methods for functionalꢀ
ization of podands with azolopyrimidine moieties consists
in cyclocondensation of α,βꢀunsaturated carbonyl comꢀ
pounds (chalcones) with aminoazoles, in particular, with
3ꢀaminoꢀ1,2,4ꢀtriazole. A number of works14—23 thorꢀ
oughly studied effects of the nature of solvents, catalysts,
and substituents in both aminoazoles and chalcones on
regioselectivity of the reactions leading to the formation of
azoloazines. It was found that electronꢀdonating substituꢀ
ents at position 5 of the dihydroazolopyrimidine system
significantly affect the iminoꢀenamine tautomerism of the
heterocycle.14,21 However, there is virtually no data on the
influence of orthoꢀsubstituents (in particular, alkoxy
groups) in the aromatic ring of chalcone cinnamoyl fragꢀ
ments on the selectivity of formation of cyclocondensaꢀ
tion products with aminoazoles. For podands24,25 with
bulky oligooxyethylene fragment, such an influence can
be significant. For instance, earlier it was shown that oligoꢀ
ethers with terminal 2ꢀformylaryl groups can be involved
Results and Discussion
The reaction of aminotriazole 2 with chalcone podand 1
in DMF at 75—80 °C leads to the formation of four
major cyclocondensation products 4—7 (Scheme 1, Table 1).
The 1H NMR spectroscopic data of the reaction mixꢀ
tures indicate the formation of podands 3—6 and crownoꢀ
phane 7 with 1,2,4ꢀtriazolo[1,5ꢀa]pyrimidine fragment,
that confirms the earlier14—21 established fact on regiospecꢀ
ificity of the cyclocondensation process of 3ꢀaminoꢀ1,2,4ꢀ
triazole with chalcones. The 1H NMR spectra of symmetꢀ
ric podands 4 and 6 are characterized19,21 by the singlet
signals for the protons at the C(2) carbon atom of the
triazole and C(6) carbon atom of the pyrimidine rings at δ
8.55 and 7.93, respectively, whereas the unsymmetric poꢀ
dand 5 shows them at δ 8.56 and 7.96, respectively. Introꢀ
duction of the hydroxy group at position 6 of the pyrimiꢀ
dine ring (compounds 5 and 6) leads to the upfield shift of
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 941—950, May, 2011.
1066ꢀ5285/11/6005ꢀ965 © 2011 Springer Science+Business Media, Inc.

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Ovchinnikova et al.
Scheme 1
5: R1 = H, R2 = OH
6: R1 = R2 = OH
Cat stands for catalyst
the signal for the proton at the C(2) carbon atom by about
0.2 ppm.
The reaction of aminoazoles with chalcones usually
stops at the step of formation of dihydroazolopyrimiꢀ
dines.14 For podands, the process is finished by aromatiꢀ
zation with the formation of products 4—6, with their
ratios in the reaction mixtures being significantly depenꢀ
dent on the catalyst (see Table 1). For instance, a predomꢀ
inant formation of podand 4 was observed in the presence
of KOH, while in other cases the equilibrium was disꢀ
placed to the side of 6ꢀoxyꢀsubstituted 1,2,4ꢀtriazolo[1,5ꢀa]ꢀ
pyrimidine podands 5 and 6. Ability of dihydroazolopyriꢀ
midines to aromatization upon the action of air oxygen in
the reaction mixtures to form 6ꢀoxyꢀsubstituted derivaꢀ
tives is more pronounced in dihydropyrazolo[1,5ꢀa]pyrimidiꢀ
nes and dihydropyrimido[1,2ꢀa]benzimidazoles.14,22 Conꢀ
versely, for dihydrotriazolo[1,5ꢀa]pyrimidines due to
the effects of several aza groups, such an oxidation process
proceeded predominantly in the alkali alcoholic soluꢀ
tions.17 In our studies, the presence of 6ꢀoxyꢀsubstituted
products was found in all the reaction mixtures indepenꢀ
dent on the medium pH.
Table 1. Results of the reaction of chalcone podand 1 with amiꢀ
notriazole 2 according to the HPLC data
Entry
Catalyst
Solvent
Yield (%)
1 + 3*
4
5
6
7
1
2
3
4
5
KOH
KOH
Et3N
—
EtOH
DMF
DMF
DMF
DMF
2
6
6
2
4
53 12 10 18
74
4
3
12
7
50 25 12
35 42 11
19 50 22
6
4
HCl
* A mixture of the starting (1) and monosubstituted triazoloꢀ
pyrimidine podands (3) according to the 1H NMR spectra of the
reaction mixtures.
The Xꢀray diffraction data on the crystals of triꢀ
azolopyrimidine podands shows not only the structural,

Triazolopyrimidine podands and crownophanes
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 5, May, 2011
967
N(7)
C(33)
N(8)
C(32)
C(31)
C(37)
C(38)
N(6)
C(34)
C(35)
C(36)
C(30)
C(29)
O(3)
N(5)
C(28)
C(15)
C(14)
C(16)
C(18)
C(27)
C(19)
C(21)
C(20)
C(17)
C(26)
C(25)
C(22)
C(23)
C(13)
O(2)
O(1)
C(12)
C(11)
N(1)
C(7)
C(24)
C(10)
C(9)
C(6)
C(5)
N(2)
C(1)
N(4)
C(2)
C(8)
C(4)
C(3)
N(3)
Fig. 1. Molecular geometry of 1,2,4ꢀtriazolo[1,5ꢀa]pyrimidine podand 4.
N(7)
C(33)
C(32)
N(8)
O(3)
C(38)
C(37)
C(31)
C(34)
N(6)
C(36)
C(30)
C(35)
N(5)
C(29)
C(16)
C(28)
C(15)
C(27)
C(18)
C(19)
C(21)
C(14)
C(17)
C(26)
C(22)
C(23)
C(24)
O(2)
C(25)
C(20)
C(7)
O(1)
C(13)
C(12)
O(4)
C(11)
C(10)
C(9)
N(1)
C(6)
N(2)
C(1)
C(5)
C(8)
C(3)
C(2)
N(4)
C(4)
N(3)
Fig. 2. Molecular geometry of 1,2,4ꢀtriazolo[1,5ꢀa]pyrimidine podand 5.
but also conformational similarities of the molecules
(Fig. 1—3).
In particular, for podand 6 the absolute values of torꢀ
sional angles C(17)O(1)C(18)C(19), O(1)C(18)C(19)O(2),
Molecules of symmetric podands 4 and 6, which like
compound 5 formally are related to the group of comꢀ
pounds with the C2 symmetry, in crystals have the C1 symꢀ
metry. For any of the three podands 4—6, both the right
and the left spiralꢀlike direction of the oligooxyethylene
fragments is observed, set by the same conformational
C(18)C(19)O(2)C(20),
C(19)O(2)C(20)C(21),
O(2)C(20)C(21)O(3), and C(20)C(21)O(3)C(22) are
equal to 168.0, 63.6, 178.1, 86.5, 67.6, and 85.5°, respecꢀ
tively. Such a spatial geometry of molecules in crystals has
been also found earlier for chalcone podands24,25 (for exꢀ
ample, for compound 1).
sequence a—g(+)—a—g(–)—g(–)—g(–) or a—g(–)—a—g(+)
g(+)—g(+) of their units (see Fig. 1—3 and Ref. 30).
—
In addition, in molecules 4—6 all the aromatic substitꢀ
uents of the terminal groups are arranged in different planes

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Ovchinnikova et al.
N(7)
N(8)
C(35)
C(36)
C(30)
C(38)
N(6)
C(37)
C(31)
C(32)
C(34)
C(33)
N(5)
C(28)
C(29)
O(3)
O(5)
C(27)
C(15)
C(14)
C(16)
C(18)
C(26)
C(25)
C(19)
C(21)
C(20)
O(2)
C(17)
C(22)
C(23)
O(1)
C(13)
O(4)
C(24)
C(12)
C(11)
N(1)
C(10)
C(7)
C(8)
C(6)
N(2)
C(9)
C(5)
C(3)
C(1)
C(4)
N(4)
C(2)
N(3)
Fig. 3. Molecular geometry of 1,2,4ꢀtriazolo[1,5ꢀa]pyrimidine podand 6.
with respect to each other. For example, the phenyl subꢀ
stituents C(12)—C(17)/C(7)—C(8) and C(22)—C(27)/
C(31)—C(32) are turned from the plane of C(10)—C(11)
and C(29)—C(30) azoloazine rings, respectively, by
the angles 45.2/33.1° and 47.0/27.3° for compound 4,
48.6/31.3° and 48.0/34.9° for compound 5, and 50.7/30.4°
and 47.4/38.4° for compound 6.
(IMHB) of the type O—H...O with the hydroxy groups of
azoloazines. The hydrogen bond has the following paraꢀ
meters: the distances O(4)—H...O(1) and O(4)—H...O(2)
are equal to 2.00 and 2.38 Å, whereas the distances
O(5)—H...O(3) and O(5)—H...O(2) are equal to 1.93 and
2.51 Å, respectively.
Podands 4—6 due to their conformational specificities
can be related to the group of compounds with the axial
and planar chirality.31—33 According to the Xꢀray diffracꢀ
tion data, the spiral character of molecules of these comꢀ
pounds (see Fig. 1—3) can be due to both the axial chiralꢀ
ity (because of hindered rotation around simple C—C
bonds of the sp2—sp2ꢀtype between the bulky bridged aryl
and triazolopyrimidine substituents) and the planar chiralꢀ
ity (because of stabilization of the synclinal conformation
of the oxyethylene units, which provides the spiralꢀlike
geometry of the polyether fragment). It is known that sigꢀ
nificant conformational differences in such compounds,
helicates and atropoisomers,31—33 can lead to diasteꢀ
reotopic effect of substituents, which can be registered by
NMR spectroscopy. Thus, if for compound 4 this effect is
leveled in solutions, that is seen from the "symmetric" 1H
and 13C NMR spectra, then for podand 6 the picture is
quite the opposite. The differences in the conformation
parameters of the oligooxyethylene fragment and terminal
groups in podand 6 are preserved in solution, by all acꢀ
counts, due to the bifurcated IMHB of the hydrogen atoms
of OH groups with the bridged oxygen atoms of the polyꢀ
ether fragment. This phenomenon can be the reason for
For compounds 4 and 5, the Xꢀray diffraction study at
295(2) K established that the conformationally labile oligoꢀ
oxyethylene fragment is disordered. The disordering of the
polyether chain of the crown ether molecules and their
acyclic analogs in crystals is a frequent enough phenoꢀ
menon, if the Xꢀray diffraction studies are performed at
room temperature. The trioxydiethylene fragment in poꢀ
dand 4 is disordered over two positions with the populaꢀ
tion coefficient 0.5. In compound 5, position of the OH
group is disorder over two positions with the population
coefficients 0.5, and a flexible chain of the polyether fragꢀ
ment is also disordered. However, unlike 4, positions of
the bridged oxygen atoms O(1) and O(3) are stabilized
due to the specific interactions with the hydroxy group of
the azinoazole ring. The distances O(4)—H...O(1) and
O(4)—H...O(2) for podands 4 and 5 are equal to 1.89 and
2.46 Å (2.48 and 1.93 Å for the polyether fragment in the
second position), respectively. The fact that such interacꢀ
tions arise and are able to affect lability of the oligooxyꢀ
ethylene fragment is confirmed by the structure of comꢀ
pound 6, in which this fragment is not disordered, whereas
the bridged oxygen atoms are fixed in positions corresꢀ
ponding to the geometry of intramolecular hydrogen bonds
1
the "unsymmetry" of the H and 13C NMR spectra. In

Triazolopyrimidine podands and crownophanes
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 5, May, 2011
969
fact, the 1H NMR spectra of compound 6 obtained at
22 °C exhibit two singlets for the protons at the carbon
atoms C(2) and C(2´) of the azole rings at δ 8.38 and 8.36
and two singlets for the protons of the OH groups at 9.50
and 9.44 (see Scheme 1 and Experimental). The 13C NMR
spectra show nonequivalence of many pairs of "symmetꢀ
ric" carbon atoms, and the highest value of nonequivaꢀ
lence is observed for the carbon atoms of the azolopyrimidine
fragment: ΔδC(2) = 0.1 ppm, ΔδC(5) = ΔδC(7) = 0.06 ppm,
while the chemical shifts for the carbon atoms C(6) and
C(6´) are equivalent. Additional NMR experiments gave
indirect confirmations for our suggestions. Thus, dilution
of the solution of compound 6 in DMSOꢀd6 produced no
changes of the chemical shifts for the protons of the hydroxy
groups, that indicates the presence of stable IMHB.
When the spectra were recorded at elevated temperature,
the signals for the protons H(2) and H(2´) of the azole
rings broadened and became closer. These signals coalesce
at 49 °C together with simplification of the spectrum in
the region of signals for the oxymethylene protons, indiꢀ
cating an increase of general symmetry of molecules of
podand 6.
Dihydroazolopyrimidine podands were not isolated in
none of the dihydro forms because of their strong tendenꢀ
cy to oxidation with air oxygen. Macrocyclic product 7
proved the only dihydro derivative stable to oxidation (see
Scheme 1), which is stabilized in the 6,7ꢀdihydro form. In
turn, the high yields of unsymmetric products 5 and 7 (see
Table 1) can indicate that the bulky polyether fragment
affects reactivity of terminal groups in compound 1. It has
been noted earlier24 that molecules of chalcone podand 1
in crystals have a spiralꢀlike geometry with close terminal
groups (according to the Xꢀray diffraction data, the disꢀ
tance between the Cβꢀatoms of the propenone fragments
is 8 Å) in the form of pseudocyclic structure, determined
by the gauche conformation of the OCH2CH2O units
(Fig. 4, a). Most likely, due to the complexation ability of
the polyether chain13,30 with respect to the molecules of
reagent or solvent, such a structure of chalcone podand
can be also preserved in solutions. The presence of such
a pseudocyclic cavity can hinder access of the reagent
molecules to the reaction centers of chalcone podand,
coordinating only one of them and thus demonstrating
different reactivity of terminal groups of compound 1. Note
that the yields of crownophane 7 depending on the catalyst
used indicate that the equilibrium of the reaction in the
presence of KOH is significantly shifted to the side of
product 7 and, conversely, its yield considerably decreases
down to the trace amounts in other cases (see Table 1, cf. enꢀ
tries 1, 2 and 3, 4). We have observed analogous dependence
earlier in the synthesis of 25ꢀmethylꢀ23,29ꢀdiphenylꢀ8,11,14ꢀ
trioxaꢀ24ꢀazahexacyclo[20.8.0.02,7.015,20.021,26.025,30]ꢀ
triacontaꢀ2,4,6,15(20),16,18,23,28ꢀoctaenꢀ27ꢀone.29 To
sum up, the additional intramolecular proximity of the
reactive terminal groups in molecules of compound 1
can be due to both the gaucheꢀeffect from the polyether
fragment of the chalcone podand and the template effect
of potassium ions resulting from the complexation
with the ligand. Note that when a polar protic solvent,
ethanol, was used, whose molecules can provide addiꢀ
tional stabilization of such complexes, the yield of
the macrocyclic product increased. A concerted action
of aforementioned effects provides high regioselectivity
of the crownophane 7 formation process, which can
follow the two possible sequences of cascade reactions
(Scheme 2).
Path A (see Scheme 2) consists of a cascade of reacꢀ
tions including intermolecular and intramolecular Michael
additions (intermediates 8 and 9) and cyclization in the
final step of the synthesis to furnish compound 7. In turn,
path B leads to the unsymmetric dihydropyrimidine poꢀ
dand 10 through the intermolecular Michael addition and
cyclocondensation. Further intramolecular addition at the
βꢀcarbon atom of the propenone fragment34 of the neighꢀ
boring terminal group in the intermediate 10 leads to
βꢀadduct 7.
The formation of crown ether 11 (see Ref. 29) as a result
of the reaction of chalcone podand 1 with urea under
conditions of alkaline catalysis (KOH) (Scheme 3) can be
an argument in favor of the cascade mechanism A. In
addition, the structural similarity (Xꢀray diffraction data)
of crownophanes 7 and 11 is obvious and comes to the
a
b
c
Fig. 4. Molecular geometry of chalcone podand 1 (a) and crownophanes 7 (b) and 11 (c) (according to the Xꢀray diffraction study).

970
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 5, May, 2011
Ovchinnikova et al.
Scheme 2
same space geometry of the polyether fragment with idenꢀ
tical a—g(+)—a—a—g(–)—a sequence of the oxyethylꢀ
ene units (Fig. 4, b, c and 5). The angle (121.57°) between
the meanꢀsquare planes, passing through the atoms
C(20)—C(15) and C(26)—C(21) of the phenoxy substiꢀ
tuents in compound 7, virtually coincides with the analoꢀ
gous angle in crownophane 11. Stereoisomerism of the
aliphatic fragment C(4a)—C(20a)—C(20) in crownophane
7 (see Scheme 2) is identical to that of similar fragment in
crownophane 11 and differs from that described earlier for
the βꢀadduct with chalcone.34
Another indirect confirmation of the initial sequence
of intermolecular and intramolecular Michael additions
(see Scheme 2, path A) can be the antiparallel stereoorienꢀ
tation of the terminal chalcone groups in the starting comꢀ
pound 1, which is observed in the geometry of crownoꢀ
phanes 7 and 11 (see Fig. 4, b, c). Such a mutual arrangeꢀ
ment of reactive groups of chalcone podand together with
the template and gauchꢀeffects, most likely, provides the
high stereoselectivity of the formation of molecules of only
one stereoisomer 7 (racemate) with three asymmetric cenꢀ
ters C(35), C(34), C(33) with the relative configuration
racꢀ(35S*,34R*,33S*) (the numeration is given as in the
Xꢀray diffraction data).
Scheme 3
The 1H NMR spectra of crownophane 7 are characterꢀ
ized by an unusually highꢀfield shifts for the protons H(20)
and H(5) in the region δ 3.16 and 5.59, respectively (Fig. 6),
that is explained by the shielding effect of the triazoloꢀ

Triazolopyrimidine podands and crownophanes
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 5, May, 2011
971
C(6)
C(5)
C(7)
C(8)
C(30)
C(19)
C(4)
C(18)
O(3)
C(3)
C(20)
C(29)
O(2)
C(17)
C(16)
C(28)
C(27)
C(25)
C(26)
C(36)
C(34)
C(24)
C(15)
C(33)
N(1)
O(1)
C(35)
C(21)
C(23)
C(1)
N(4)
C(22)
C(32)
C(31)
C(10)
N(2)
C(14)
C(2)
O(4)
N(3)
C(9)
C(13)
C(12)
C(11)
Fig. 5. Molecular geometry of crownophane 7 (according to the Xꢀray diffraction study).
pyrimidine ring. According to the Xꢀray diffraction data,
the distances between the hydrogen atom H(20) and H(5)
and the plane of the condensed ring are 2.25 and 2.40 Å,
respectively, and these both atoms are placed inside the
cone of magnetic anisotropy. It is probable, that this conꢀ
formation is also preserved in solution, that is confirmed
by the presence of the crossꢀpeak between the H(5) and
H(2) in the 1H—1H NOESY 2D spectrum.
ty of cyclocondensation process and degree of oxidation of
triazolopyrimidine podands. We also showed the role of
potassium ions present in the reaction medium, which
coordinate with oligooxyethylene cavity of the molecule
of chalcone podand and provide additional intramolecuꢀ
lar proximity of their terminal groups, thus shifting the
equilibrium to the side of intramolecular Michael addiꢀ
tion. These cascade transformations result in the formaꢀ
tion of stable 6,7ꢀdihydroꢀ1,2,4ꢀtriazolo[1,5ꢀa]pyrimidine
crownophane in form of only one diastereomer with three
asymmetric centers C(35), C(34), C(33) of relative conꢀ
In conclusion, in the present work we studied effects of
such factors as the nature of catalyst, solvent, and spatial
geometry of the starting chalcone podand on the selectiviꢀ
a
b
Fig. 6. Stereoorientation of hydrocarbon skeleton C(4a)—C(20a)—C(20)—C(24) in crownophane 7 and selected correlations observed
in the 1H—1H NOESY (a) and 1H—13C HMBC (b) 2D spectra.

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Ovchinnikova et al.
(C(7)); 155.24 (C(3a)); 155.67 (C(2)); 156.16 (C(2´)); 160.00
(C(5)). IR, ν/cm–1: 689, 703, 762 (arom.); 853, 878, 920, 938,
figuration racꢀ(35S*,34R*,33S*) (the numeration is given
as in the Xꢀray diffraction data).
s
969, 1029; 1052 (ν , Carom—O—Calk); 1113, 1132, 1143, 1168,
as
s
as
1194 (ν , ν , Calk—O); 1254 (ν , Carom—O—Calk); 1283, 12948,
1379, 1447, 1458, 1491; 1535, 1546, 1579, 1600, 1611, 1618
(ν, C=C, C=N); 2866, 2896, 2936, 2967 (δ, Calk—H); 3077,
3111 (δ, Carom—H). Found (%): C, 70.36; H, 4.76; N, 17.06.
C38H30N8O3. Calculated (%): C, 70.58; H, 4.64; N, 17.34.
5ꢀPhenylꢀ7ꢀ[2ꢀ(2ꢀ{2ꢀ[2ꢀ(5ꢀphenylꢀ1,2,4ꢀtriazolo[1,5ꢀa]ꢀ
pyrimidinꢀ7ꢀyl)phenoxy]ꢀethoxy}ethoxy)phenyl]ꢀ1,2,4ꢀtriazoloꢀ
[1,5ꢀa]pyrimidinꢀ6ꢀol (5). M.p. 197—199 °C (MeCN). 1H NMR,
δ: 3.25—3.35 (m, 4 H, H(12´), H(12´´ )); 3.88—3.97 (m, 4 H,
H(11´), H(11´´ )); 7.08—7.19 (m, 4 H, H(3´´ ), H(3´´´), H(5´´ ),
H(5´´´)); 7.46—7.59 (m, 9 H, H(6´´´), H(4´´ ), H(4´´´), H(9´´ ),
H(9´´´), H(10´´ ), H(10´´´)); 7.76 (dd, 1 H, H(6´´ ), J = 7.6 Hz,
J = 1.6 Hz); 7.99 (s, 1 H, H(6)); 8.02 (m, 2 H, H(8´´´)); 8.28
(m, 2 H, H(8´´)); 8.36 (s, 1 H, H(2´)); 8.56 (s, 1 H, H(2)); 9.42
(s, 1 H, OH). 13C NMR, δ: 67.79, 67.85 (C(11´), C(11´´ )); 68.51,
68.56 (C(12´), C(12´´ )); 108.79 (C(6)); 112.97, 113.01 (C(3´´ ),
C(3´´´)); 116.70 (C(1´´´)); 119.19 (C(1´´ )); 120.51, 120.65 (C(5´´ ),
C(5´´´)); 127.64 (C(8´´)); 128.08 (C(9´´´)); 129.03 (C(9´´ )); 129.54
(C(8´´´)); 129.93 (C(10´´´)); 131.10 (C(6´´ )); 131.26 (C(10´´));
131.56 (C(4´´´)); 131.97 (C(6´´´)); 132.62 (C(4´´)); 133.46
(C(7´)); 136.04 (C(7´´)); 136.14 (C(7´´´)); 138.91 (C(6´)); 145.86
(C(7)); 150.62 (C(3a´)); 155.01 (C(2´)); 155.26 (C(3a)); 155.69
(C(2)); 156.12 (C(5´)); 156.23 (C(2´´)); 156.68 (C(2´´´)); 160.10
(C(5)). IR, ν/cm–1: 686, 755, 786, 798 (arom.); 825, 852, 923,
Experimental
IR spectra were recorded on a Spectrum One IR Fourierꢀ
spectrometer (Perkin—Elmer) using a diffuse reflectance samꢀ
pling accessory (DRA). 1H and 13C NMR spectra were recorded
on a Bruker DRXꢀ400 spectrometer (400 and 100 MHz, respecꢀ
tively) in DMSOꢀd6 relatively to Me4Si and DMSOꢀd6 (δC 39.5)
as internal standards. Full assignment of signals in the 1H and
13C NMR spectra was performed using twoꢀdimensional experiꢀ
ments COSY, NOESY, HSQC, HMBC. Melting points were
measured on a Boetius heating microstage. Reaction progress
and purity of compounds were monitored by TLC on Silufolꢀ254
plates, visualized in iodine vapors.
Reversedꢀphase HPLC was performed on an Agilent 1100
analytic liquid chromatograph, using a LiChrosorb RPꢀ18, LKB,
4.0×250 mm column with the particle sizes 5 μm and temperaꢀ
ture of the column 35 1 °C. Water was used as a mobile phase A,
60% aqueous acetonitrile — as a mobile phase B. Elution was
performed as follows: first with the gradient from 0 to 100%
phase B over 20 min, then the isocratic regime with the mobile
phase B to 40 min, the rate of solvent flow was 0.8 mL min–1
Samples were injected (10 μL) as solutions in DMF. Detection
was performed using a diode matrix detector in the UV range on
the wavelength 314 nm.
Chalcone podand 1 was synthesized according to the known
procedure.24
.
s
as
s
1018; 1051 (ν , Carom—O—Calk); 1125, 1144, 1172 (ν , ν ,
as
Calk—O); 1246 (ν , Carom—O—Calk); 1277, 1379, 1402, 1449,
1491; 1518, 1536, 1579, 1602, 1612 (δ, C=C, C=N); 2875, 2930
(δ, Calk—H); 3060, 3085 (δ, Carom—H); 3364 (O—H). Found (%):
C, 68.96; H, 4.55; N, 16.83. C38H30N8O4. Calculated (%):
C, 68.88; H, 4.53; N, 16.92.
Reaction of chalcone podand 1 with aminotriazole 2 (general
procedure). A mixture of chalcone podand 1 (0.25 g, 0.48 mmol)
and 3ꢀaminoꢀ1,2,4ꢀtriazole (0.09 g, 0.96 mmol) in DMF (10 mL)
in the presence of the corresponding catalyst (0.48 mmol of
KOH, 0.48 mmol of Et3N, or 0.06 mL of 1.15 M aq. HCl) or
without catalyst (see Table 1) was heated at 80 °C for 35 h. Water
was added to the reaction mixture, a precipitate formed was
filtered off and washed with water several times. Purification
and separation of products 3—7 were performed by column
chromatography (SiO2), eluting with the benzene—ethyl aceꢀ
tate—nꢀbutanol (25 : 25 : 2) solvent system. Products 4 and 7
were isolated from the reaction mixture (DMF or EtOH, see
Table 1) in 70% (0.22 g) and 18% (0.05 g) yields, respectively.
Products 5 and 6 were isolated from the reaction mixture (DMF,
HCl) in 46% (0.15 g) and 22% (0.07 g) yields, respectively. The
ratios of 3—7 were evaluated using 1H NMR spectra of the reacꢀ
tion mixtures and by the reversedꢀphase HPLC. Retention times
for compounds were as follows: 16.9 min (for 8), 20.7 min (for 6),
22.0 min (for 5), 23.2 min (for 4), 26.9 min (for 3), 27.9 min
(for 7).
1,5ꢀBis[2ꢀ(1ꢀ(6ꢀhydroxyꢀ5ꢀphenylꢀ1,2,4ꢀtriazolo[1,5ꢀa]ꢀ
pyrimidinꢀ6ꢀolꢀ7ꢀyl)phenoxy)]ꢀ3ꢀoxapentane
(6).
M.p.
204—206 °C (EtOH). 1H NMR, δ: 3.21—3.33 (m, 4 H, H(12´),
H(12´´)); 3.86—3.98 (m, 4 H, H(11´), H(11´´)); 7.10—7.19
(m, 4 H, H(3´´), H(3´´´), H(5´´), H(5´´´)); 7.50—7.55 (m, 10 H,
H(6´´), H(6´´´), H(4″), H(4´´´), H(9´´), H(9´´´), H(10´´), H(10´´´));
8.03—8.08 (m, 4 H, H(8´´), H(8´´´)); 8.36, 8.38 (both s, 1 H
each, H(2), H(2´)); 9.44, 9.50 (both br.s, 2 H, OH). 13C NMR,
δ: 67.86, 67.88 (C(11´), C(11´´)); 68.57, 68.59 (C(12´), C(12´´));
113.08 (C(3´´), C(3´´´)); 116.74 (C(1´´), C(1´´´)); 120.66 (C(5´´),
C(5´´´)); 128.10, 128.15 (C(9´´), C(9´´´)); 129.55 (C(8´´), C(8´´´));
129.96, 129.98 (C(10´´), C(10´´´)); 131.54 (C(4´´), C(4´´´)); 132.00
(C(6´´), C(6´´´)); 133.55, 133.61 (C(7), C(7´)); 136.16 (C(7´´),
C(7´´´)); 138.91 (C(6), C(6´)); 150.59, 150.63 (C(3a), C(3a´));
154.93, 155.03 (C(2), C(2´)); 156.20, 156.26 (C(5), C(5´)); 156.73
(C(2´´), C(2´´´)). IR, ν/cm–1: 699, 751, 797 (arom.); 821, 853,
s
926, 1022; 1049, 1084 (ν , Carom—O—Calk); 1119, 1146, 1175
as
s
as
1,5ꢀBis[2ꢀ(1ꢀ(5ꢀphenylꢀ1,2,4ꢀtriazolo[1,5ꢀa]pyrimidinꢀ7ꢀ
yl)phenoxy)]ꢀ3ꢀoxapentane (4). M.p. 152—155 °C. H NMR, δ:
(ν , ν , Calk—O); 1243 (ν , Carom—O—Calk); 1277, 1329, 1400,
1449, 1453, 1488; 1518, 1602 (δ, C=C, C=N); 2877, 2935
(δ, Calk—H); 3048, 3085 (δ, Carom—H); 3333 (O—H). Found (%):
C, 67.28; H, 4.48; N, 16.46. C38H30N8O5. Calculated (%):
C, 67.25; H, 4.42; N, 16.52.
1
3.36 (m, 4 H, H(12´)); 3.98 (m, 4 H, H(11´); 7.13 (dd, 2 H,
H(3´), J = 8.4 Hz, J = 1.0 Hz); 7.15 (dd, 2 H, H(5´), J = 7.6 Hz,
J = 7.5 Hz, J = 1.0 Hz); 7.45 — 7.52 (m, 6 H, H(9´), H(10´));
7.55 (ddd, 2 H, H(4´), J = 8.4 Hz, J = 7.5 Hz, J = 1.8 Hz); 7.74
(dd, 2 H, H(6´), J = 7.6 Hz, J = 1.8 Hz); 7.93 (s, 2 H, H(6));
8.23 (m, 4 H, H(8´)); 8.55 (s, 2 H, H(2)). 13C NMR, δ: 67.70
(C(11´)); 68.48 (C(12´)); 108.71 (C(6)); 112.89 (C(3´)); 119.09
(C(1´)); 120.46 (C(5´)); 127.57 (C(8´)); 128.94 (C(9´)); 131.09
(C(6´)); 131.16 (C(10´)); 132.57 (C(4´)); 135.98 (C(7´)); 145.73
1ꢀPhenylꢀ2ꢀ(21ꢀphenylꢀ10,11,13,14,20,20aꢀhexahydroꢀ4aHꢀ
dibenzoꢀ[13,14:8,9][1,4,7]trioxacyclotetradecino[11,10ꢀe]ꢀ
[1,2,4]triazolo[1,5ꢀa]pyrimidinꢀ20ꢀyl)ꢀ1ꢀethanone (7). M.p.
216—218 °C (MeCN). 1H NMR, δ: 3.16 (ddd, 1 H, H(20),
J = 11.2 Hz, J = 7.3 Hz, J = 4.9 Hz); 3.75 (m, 1 H, OCH2);
3.94—4.15 (m, 6 H, H(24), OCH2); 4.21, 4.40, 4.51 (all m,

Triazolopyrimidine podands and crownophanes
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 5, May, 2011
973
Table 2. Crystal and Xꢀray diffraction experimental parameters for compounds 4—7
Parameter
4
5
6
7
Molecular formula
Molecular weight
Crystal system
Z
Space group
a/Å
b/Å
c/Å
α/deg
β/deg
С38Н30N8О3•C4H10
720.82
O
С38Н30N8О4•C4H10
736.82
O
С38Н30N8О5
678.70
С36Н32N4О4
584.66
Monoclinic
4
Monoclinic
4
Triclinic
2–
Triclinic
2–
Р21/n
Р21/с
Р 1
Р 1
15.872(3)
14.484(2)
17.852(3)
90
115.858(17)
90
15.633(2)
14.6525(13)
17.893(3)
90
115.883(5)
90
3687.6(8)
1.327
1552
9.378(2)
13.577(3)
14.025(3)
106.77(2)
96.456(18)
108.691(19)
1577.8(6)
1.429
10.459(2)
11.531(3)
13.8534(17)
82.86(15)
71.776(14)
70.33(2)
1494.0(5)
1.300
γ/deg
V/Å3
3693.2(11)
1.296
dcalc/g cm–3
F(000)
1520
708
616
μ(MoꢀKα)/mm–1
Crystal size/mm
Region of scanning, θ/deg
Range of h, k, l
0.086
0.090
0.098
0.086
0.47×0.26×0.13
2.68—26.36
–19 ≤ h ≤ 19,
–16 ≤ k ≤ 18,
–22 ≤ l ≤ 20
23369
0.48×0.43×0.37
2.69—28.30
–19 ≤ h ≤ 20,
–7 ≤ k ≤ 19,
–23 ≤ l ≤ 23
35302
0.48×0.32×0.18
2.78—28.28
–12 ≤ h ≤ 11,
–18 ≤ k ≤17,
–15 ≤ l ≤ 18
12022
0.49×0.27×0.01
3.00—26.37
–13 ≤ h ≤ 13,
–14 ≤ k ≤13,
–17 ≤ l ≤ 17
12174
Number of measured reflections
Number of independent
reflections with I > 2σ(I)
Rint
7195
8941
7423
5831
0.0589
2299
0.0593
3216
0.0247
3027
0.0443
2403
Rꢀfactors on I > 2σ(I)
R1
wR2
0.0467
0.0573
0.0508
0.1005
0.0449
0.0975
0.0406
0.0356
Rꢀfactors on all the reflections
R1
wR2
0.1953
0.0647
1.005
0.1549
0.1119
0.998
0.1266
0.1054
1.001
0.1361
0.0396
0.939
Qꢀfactor on F 2
Residual electron
–0.129/0.159
–0.175/0.275
–0.320/0.241
–0.138/0.150
–3
density (min/max)/e Å
1 H each, OCH2); 5.37 (dd, 1 H, H(20a), J = 11.2 Hz,
J = 1.0 Hz); 5.59 (dd, 1 H, H(5), J = 7.7 Hz, J = 1.0 Hz); 6.07
(s, 1 H, H(4a)); 6.23 (d, 1 H, H(16), J = 8.2 Hz); 6.46—6.52
(m, 2 H, H(18), H(19)); 6.69 (td, 1 H, H(6), J = 7.7 Hz, J = 1.0 Hz);
6.74 (ddd, 1 H, H(17), J = 8.2 Hz, J = 6.3 Hz, J = 3.0 Hz); 7.06
(tm, 2 H, H(3´), J = 7.7 Hz); 7.13 (dd, 1 H, H(8), J = 8.4 Hz,
J = 1.0 Hz); 7.19—7.25 (m, 2 H, H(4´), H(7)); 7.32 (m, 2 H,
H(2´)); 7.51 (tm, 2 H, H(3´´ ), J = 7.5 Hz); 7.61 (tm, 1 H, H(4´´ ),
J = 7.5 Hz); 7.84 (m, 2 H, H(2´´ )); 8.24 (s, 1 H, H(2)). 13C NMR,
δ: 39.65 (C(24)); 41.59 (C(20)); 41.90 (C(20a)); 54.67 (C(4a));
65.31, 66.75, 68.50, 68.86 (C(14), C(13), C(11), C(10)); 110.29
(C(16)); 111.84 (C(8)); 119.53 (C(18)); 120.37 (C(6)); 123.74
(C(4b)); 124.81 (C(5)); 127.06 (C(19a)); 127.25 (C(2´)); 127.49
(C(3´)); 127.77 (C(2´´ )); 128.27 (C(17)); 128.68 (C(3´´ )); 129.57
(C(7)); 131.06 (C(19)); 131.27 (C(4´)); 133.12 (C(4´´ )); 136.54
(C(1´´ )); 136.98 (C(1´)); 151.79 (C(2)); 154.29 (C(22a)); 154.84
(C(8a)); 156.08 (C(15a)); 177.39 (C(21)); 199.55 (C(23)). IR,
ν/cm–1: 682, 694, 743, 755, 765 (arom.); 852, 875, 922, 950,
(δ, C=O); 2867, 2884, 2930 (δ, Calk—H); 3038, 3063 (δ, Carom—H).
Found (%): C, 73.66; H, 5.65; N, 9.56. C36H32N4O4. Calculatꢀ
ed (%): C, 73.97; H, 5.47; N, 9.59.
Xꢀray diffraction study. Crystals of triazolopyrimidine poꢀ
dands 4—6 were obtained by the slow concentration of their
solutions in DMF—butanol (1 : 1), whereas crystals of 6,7ꢀdiꢀ
hydroꢀ1,2,4ꢀtriazolo[1,5ꢀa]pyrimidine crownophane 7 — of
its solution in acetonitrile. Xꢀray diffraction study of the comꢀ
pounds was performed on a Xcalibur 3 diffractometer with
a CCDꢀdetector (ωꢀscanning, MoKαꢀirradiation, λ = 0.71073 Å,
graphite monochromator, T = 295(2) K). The set of reflections
was obtained and processed using the CrysAlis program packꢀ
age.35 The structures were solved by the direct method and
refined by the fullꢀmatrix least squares method first in the isotroꢀ
pic and then in the anisotropic approximation on F2 for all
the nonhydrogen atoms using the SHELXSꢀ97 and SHELXLꢀ97
program packages.36 Some of the hydrogen atoms were found
in the differential synthesis and included in the refinement in
the isotropic approximation, some were placed in the geoꢀ
metrically calculated positions and refined using the riding modꢀ
el. The main crystallographic data and refinement parameters
s
s
987, 1001; 1056 (ν , Carom—O—Calk); 1117, 1135 (νas, ν ,
as
Calk—O); 1231, 1245 (ν , Carom—O—Calk); 1261, 1261, 1356,
1450, 1494, 1515; 1561, 1588, 1600 (δ, C=C, C=N); 1686

974
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 5, May, 2011
Ovchinnikova et al.
for the structures 4—7 are given in Table 2. The experimental
Xꢀray diffraction data for the structures 4—7 were deposited
with the Cambridge Structural Database with the numbers
CCDC822574, CCDC822573, CCDC822572, CCDC822571,
respectively.
17. S. M. Desenko, V. D. Orlov, V. V. Lipson, Khim. Geterotsikl.
Soedin., 1990, 1638 [Chem. Heterocycl. Compd. (Engl. Transl.),
1990, 26, 1362].
18. S. M. Desenko, Kh. Estrada, V. D. Orlov, O. A. Ponomarev,
Khim. Geterotsikl. Soedin., 1991, 105 [Chem. Heterocycl. Comꢀ
pd. (Engl. Transl.), 1991, 27, 88].
This work was financially supported by the Council on
Grants at the President of the Russian Federation (Proꢀ
gram of State Support for Leading Scientific Schools of
the Russian Federation, Grant NShꢀ65261.2010.3) and
the Presidium of the Ural Branch of the Russian Academy
of Sciences (Project Nos 09ꢀPꢀ23ꢀ2001, 09ꢀIꢀ3ꢀ2004, and
09ꢀPꢀ3ꢀ2001).
19. V. V. Lipson, S. M. Desenko, V. D. Orlov, M. N. Shirobokoꢀ
va, V. N. Chernenko, L. I. Zinov´eva, Khim. Geterotsikl.
Soedin., 2000, 1542 [Chem. Heterocycl. Compd. (Engl. Transl.),
2000, 36, 1329].
20. R. V. Rudenko, S. A. Komykhov, V. I. Musatov, S. M. Desenꢀ
ko, J. Heterocycl. Chem., 2009, 46, 285.
21. S. M. Desenko, E. S. Gladkov, N. V. Getmanskii, I. M.
Zemlin, V. D. Orlov, Khim. Geterotsikl. Soedin., 1999, 678
[Chem. Heterocycl. Compd. (Engl. Transl.), 1999, 35, 608].
22. C. M. Desenko, V. D. Orlov, V. V. Lipson, O. V. Shishkin,
K. A. Potekhin, Yu. T. Struchkov, Khim. Geterotsikl. Soeꢀ
din., 1993, 109 [Chem. Heterocycl. Compd. (Engl. Transl.),
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23. C. M. Desenko, E. S. Gladkov, S. A. Komykhov, O. V.
Shishkin, V. D. Orlov, Khim. Geterotsikl. Soedin., 2001, 811
[Chem. Heterocycl. Compd. (Engl. Transl.), 2001, 37, 747].
24. I. G. Ovchinnikova, O. V. Fedorova, P. A. Slepukhin, I. A.
Litvinov, G. L. Rusinov, Kristallografiya, 2009, 54, 32 [Crysꢀ
tallogr. Rep. (Engl. Transl.), 2009, 54, 31].
25. I. G. Ovchinnikova, O. V. Fedorova, E. G. Matochkina,
M. I. Kodess, P. A. Slepukhin, G. L. Rusinov, Izv. Akad.
Nauk, Ser. Khim., 2009, 1150 [Russ. Chem. Bull., Int. Ed.,
2009, 58, 1180].
26. M. S. Zhidovinova, O. V. Fedorova, G. L. Rusinov, I. G.
Ovchinnikova, Mol. Diversity, 2003, 6, 323.
27. A. N. Levov, Le Tuan An´, A. I. Komarova, V. M. Strokina,
A. T. Soldatenkov, V. N. Khrustalev, Zh. Org. Khim., 2008,
44, 457 [Russ. J. Org. Chem. (Engl. Transl.), 2008, 44, 456].
28. Le Tuan An´, A. N. Levov, A. T. Soldatenkov, R. D.
Gruzdev, Chyong Khong Khieu, Zh. Org. Khim., 2008, 44,
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29. I. G. Ovchinnikova, O. V. Fedorova, E. G. Matochkina,
I. M. Kodess, A. A. Tumashev, P. A. Slepukhin, G. L. Rusiꢀ
nov, V. N. Charushin, Makrogeterotsikly [Macroheterocycles],
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Received November 26, 2010;
in revised form February 28, 2011