2-Acyl(aroyl)-1,1,3,3-tetracyanopropenides: III.* heterocyclization by the action of hydrogen halides

Article abstract of DOI:10.1134/S107042801110006X

2-Acyl(aroyl)-1,1,3,3-tetracyanopropenides reacted with hydrogen halides along two concurrent pathways with formation of furan or pyridine derivatives. The reaction in butan-2-ol afforded 2-amino-4-acyl-(aroyl)-6-halopyridine-3,5- dicarbonitriles, whereas

Full text of DOI:10.1134/S107042801110006X

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2011, Vol. 47, No. 10, pp. 1492–1497. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © S.V. Karpov, Ya.S. Kayukov, I.N. Bardasov, O.V. Kayukova, K.V. Lipin, O.E. Nasakin, 2011, published in Zhurnal Organicheskoi
Khimii, 2011, Vol. 47, No. 10, pp. 1467–1472.
2-Acyl(aroyl)-1,1,3,3-tetracyanopropenides:
III.* Heterocyclization by the Action of Hydrogen Halides
S. V. Karpova, Ya. S. Kayukovb, I. N. Bardasova, O. V. Kayukovab,
K. V. Lipina, and O. E. Nasakina
a I.N. Ul’yanov Chuvash State University, Moskovskii pr. 15, Cheboksary, 428015 Russia
e-mail: kaukovyakov@mail.ru
b Chuvash Agricultural Academy, Cheboksary, Russia
Received May 17, 2011
Abstract—2-Acyl(aroyl)-1,1,3,3-tetracyanopropenides reacted with hydrogen halides along two concurrent
pathways with formation of furan or pyridine derivatives. The reaction in butan-2-ol afforded 2-amino-4-acyl-
(aroyl)-6-halopyridine-3,5-dicarbonitriles, whereas the major products in the reactions with HCl and HBr in
aqueous solution were the corresponding 2-(5-amino-2-aryl-2-chloro(bromo)-4-cyano-2,3-dihydrofuran-3-
ylidene)malononitriles. The reaction with aqueous hydrogen iodide was accompanied by reductive deiodination
and produced 2-(5-amino-2-aryl-4-cyano-2,3-dihydrofuran-3-ylidene)malononitriles.
DOI: 10.1134/S107042801110006X
2-Acyl(aroyl)-1,1,3,3-tetracyanopropenides I [2]
are promising starting compounds for the synthesis of
various heterocycles. The presence of two electrophilic
centers, carbonyl and cyano groups, in the anions of
salts I, gives rise to two possible heterocyclization
pathways by the action of nucleophilic reagents; the
nature of counterion (alkali metal or ammonium cation)
almost does not affect the reactivity of compounds I.
We previously described the transformation of salts I
into dihydrofuran derivatives via reactions with con-
centrated hydrochloric acid [3] and with thiols in
aqueous medium under acidic conditions [1]. On the
other hand, it is known that polycyanopropenides are
typically converted into compounds of the pyridine
series [4–8]. In this case, heterocyclization is also
performed by the action of hydrogen halides which
simultaneously act as reagent and catalyst. For ex-
ample, the reaction of 2-alkyl(aryl)-1,1,3,3-tetracyano-
propenides with hydrogen chloride leads to the corre-
sponding 4-alkyl(aryl)-2-amino-6-chloropyridine-3,5-
dicarbonitriles [7], whereas 2-amino-6-chloropyridine-
3,4,5-tricarbonitrile was obtained from pentacyano-
propenide [8]. Taking the above stated into account,
we examined the possibility of using propenides I for
the synthesis of pyridine derivatives. For this purpose,
reactions of compounds I with hydrogen halides were
carried out in different solvents by mixing the reactants
in different modes.
We found that organic solvents favor formation of
pyridine derivatives. The best results were obtained
using butan-2-ol as solvent; in this case, the products
were exclusively the corresponding 2-amino-4-acyl-
(aroyl)-6-halopyridine-3,5-dicarbonitriles IIa–IIk
(Scheme 1). The reactions in other common organic
solvents, such as dioxane, acetonitrile, and acetone,
also led to formation of pyridines II, but as mixtures
with the corresponding 2-(5-amino-2-aryl-4-cyano-2-
halo-2,3-dihydrofuran-3-ylidene)malononitriles IIIa–
IIIg. The latter were obtained as the major products by
reaction of propenides I with HCl and HBr in aqueous
medium. The reaction of salts I with HI in water
followed a different pathway to produce iodine-free
2-(5-amino-2-aryl-4-cyano-2,3-dihydrofuran-3-
ylidene)malononitriles IVa–IVc (Scheme 1).
The structure of compounds IIa–IIk, IIIa–IIIg,
and IVa–IVc was determined on the basis of their
13
1H and C NMR, IR, and mass spectra. Signals from
1
protons in aryl substituents appeared in the H NMR
spectra of IIa–IIc, IIe–IIj, IIIa–IIIc, IIIe–IIIg, and
IVa–IVc in the region δ 7.15–8.06 ppm. The tert-butyl
group in compounds IId, IIk, and IIId gave rise to
a singlet at δ 1.05–1.28 ppm. Unlike pyridines IIa–IIk,
furans IIIa–IIIg and IVa–IVc characteristically dis-
* For communication II, see [1].
1492

2-ACYL(AROYL)-1,1,3,3-TETRACYANOPROPENIDES: III.
1493
Scheme 1.
R
Hlg
CN
CN
O
HHlg, H2O
H2N
R
O
O
CN
CN
HHlg, 2-BuOH
IIIa–IIIg
NC
CN
Hlg
R
CN
NH4
R
NC
CN
H2N
N
CN
CN
O
HI, H2O
IIa–IIk
Ia–Ie
H2N
CN
IVa–IVc
I, R = Ph (a), 4-ClC6H4 (b), 4-MeC6H4 (c), t-Bu (d), 4-MeOC6H4 (e); II, Hlg = Cl, R = Ph (a), 4-ClC6H4 (b), 4-MeC6H4 (c),
t-Bu (d); Hlg = Br, R = Ph (e), 4-ClC6H4 (f), 4-MeC6H4 (g); Hlg = I, R = Ph (h), 4-ClC6H4 (i), 4-MeC6H4 (j), t-Bu (k); III, Hlg = Br,
R = Ph (a), 4-ClC6H4 (b), 4-MeC6H4 (c), t-Bu (d); Hlg = Cl, R = Ph (e), 4-BrC6H4 (f), 4-MeOC6H4 (g); IV, R = Ph (a), 4-ClC6H4 (b),
4-MeC6H4 (c).
1
played in the H NMR spectra two singlets at δ 8.2–
9.0 ppm (Δδ = 0.5 ppm) from the NH2 protons instead
of a broadened singlet at δ 10.43–10.54 ppm in the
spectra of IIa–IIk. Radically different structures of
compounds IIa–IIe and IIIa–IIIg were reflected in
their 13C NMR spectra. Pyridine IIe showed signals
from the carbonyl carbon atom at δC 190.2 ppm and
two cyano groups at δC 113.03 and 114.76 ppm, where-
as three C≡N signals were present in the spectrum of
IIIe (δC 110.47, 112.44, 113.13 ppm) together with the
signal at δC 70 ppm from the =C(CN)2 carbon atom
and low-intensity signal at δC 105.34 ppm from C2 in
the furan ring [3]. Furans IVa–IVc were characterized
by the presence in their 1H NMR spectra of a singlet at
δ 6.81–6.87 ppm due to proton in position 2 of the
furan ring.
observed absorption bands assignable to C=C bond
(1590–1670 cm–1), conjugated cyano groups (2200–
2235 cm–1), and amino group (3100–3150, 3300–
3350 cm–1).
Presumably, the direction of transformation of
propenides I in reactions with hydrogen halides is
determined by the site of primary proton addition.
Here, solvation effect is crucial. Protonation in organic
solvents is likely to occur at the nitrogen atom of one
cyano group. Ketene imine A thus formed takes up
hydrogen halide molecule, and subsequent hetero-
cyclization gives six-membered pyridine ring
(Scheme 2). When the reaction is carried out in
aqueous medium, initial protonation of I involves the
carbonyl oxygen atom (intermediate B), and the sub-
sequent nucleophilic attack is directed at the carbonyl
carbon with formation of structure C which undergoes
heterocyclization with formation of furan ring, finally
leading to compounds IIIa–IIIg (Scheme 3).
The IR spectra of all isolated compounds were con-
sistent with the assumed structures. The IR spectra of
IIa–IIe contained absorption bands at 1650–1682 cm–1
due to stretching vibrations of the carbonyl group;
absorption bands at 2200–2235 cm–1 were assigned to
conjugated cyano groups, and bands at 3150–3200 and
3300– 3350 cm–1 were typical of NH stretching vibra-
tions. In the IR spectra of IIIa–IIIg and IVa–IVc we
Apart from the solvent nature, the yield and selec-
tivity also depend on the mode of addition of hydrogen
halides. The best yields of both furan and pyridine
derivatives were obtained when gaseous hydrogen
halide was slowly passed through a solution of salt I in
Scheme 2.
R
O
O
CN
CN
O
CN
CN
Hlg
NH2
NC
HN
CN
Hlg
HHlg, 2-BuOH
HHlg
R
·
R
Ia–Id
IIa–IIk
NH
NC
NC
N
H
A
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 10 2011

KARPOV et al.
1494
Scheme 3.
R
O
OH
CN
CN
OH
CN
CN
HN
Hlg
H+
Hlg–
H+
R
R
CN
CN
Ia–Ie
IIIa–IIIg
Hlg
CN
NC
NC
NC
NC
B
C
Scheme 4.
O
OH
CN
CN
OH
R
CN
CN
HN
R
H+
HI
H+
I–
R
CN
CN
Ia–Ic
B
IVa–IVc
I
–I2
CN
NC
NC
NC
NC
D
E
the corresponding solvent at 60–65°C. Dropwise ad-
dition of hydrohalic acids also ensured formation of
pyridines II in butan-2-ol, but the yields were lower.
Reaction of I with excess concentrated hydrohalic acid
led to the formation of mixtures of compounds II and
III. Thus slow addition of hydrogen halide favors
selective protonation of the substrate and its subse-
quent transformations due to solvation effect. In the re-
action with excess hydrogen halide protonation occurs
at both nitrogen and oxygen atoms, and a mixture of
products is formed.
The formation of dihydrofurans IV in the reaction
of hydrogen iodide with salts I in aqueous solution
may be rationalized taking into account reducing
power of HI and oxidative ability of intermediate iodo-
hydrin D (Scheme 4). In this case, the reaction also
begins with protonation of the carbonyl oxygen atom
with formation of zwitterion B which takes up iodide
ion to give iodohydrin D. The latter is reduced to
intermediate alcohol E by the action of excess HI, and
the subsequent heterocyclization of E yields dihydro-
furans IVa–IVc.
tion). The IR spectra were recorded on an FSM-1202
spectrometer with Fourier transform from samples dis-
persed in mineral oil. The
were measured on a Bruker DRX-500 spectrometer at
500.13 and 125.76 MHz, respectively, using DMSO-d6
as solvent and tetramethylsilane as internal reference.
The mass spectra (electron impact, 70 eV) were ob-
tained on a Shimadzu GCMS-QP2010S DI instrument.
1H and 13C NMR spectra
2-Amino-4-benzoyl-6-chloropyridine-3,5-dicar-
bonitrile (IIa). a. A solution of 2.63 g (0.01 mol) of
ammonium 2-benzoyl-1,1,3,3-tetracyanopropenide in
5 ml of butan-2-ol was heated to 70–75°C, and gase-
ous hydrogen chloride was passed through the solution
at a flow rate of 0.5–1.0 ml/s over a period of 10 min.
The mixture was cooled, and the precipitate was fil-
tered off, washed with 20 ml of water, and recrystal-
lized from 1,4-dioxane. Yield 2.2 g (78%), mp 219–
220°C. IR spectrum, ν, cm–1: 3177 (NH2), 2233 (C≡N),
1
1660 (C=O). H NMR spectrum, δ, ppm: 7.66 t (2H,
3
3
Harom, J = 7.8 Hz), 7.86 t (1H, Harom, J = 7.4 Hz),
3
8.03 d (2H, Harom, J = 7.4 Hz), 8.56 br.s and 9.01 br.s
(1H each, NH2). Mass spectrum, m/z (Irel, %): 284 (11),
282 (34). Found, %: C 59.12; H 2.55; N 19.79.
C14H7ClN4O. Calculated, %: C 59.48; H 2.50; N 19.82.
M 282.68.
The yield and purity of compounds IVa–IVc also
depended on the reaction conditions. The use of
gaseous hydrogen iodide ensured the results. Slow
addition of concentrated hydroiodic acid to aqueous
solutions of salts I afforded dihydrofurans IVa–IVc in
moderate yield.
b. A solution of 2.63 g (0.01 mol) of ammonium
2-benzoyl-1,1,3,3-tetracyanopropenide in 5 ml of
butan-2-ol was heated to 60°C, 2 ml of concentrated
hydrochloric acid was added dropwise over a period of
15 min, and the mixture was stirred for 30 min at 55–
65°C and poured into 100 ml of hot (90°C) water. The
precipitate was filtered off and washed with diethyl
ether. Yield 1.58 g (56%), decomposition point 219–
220°C (from 1,4-dioxane).
EXPERIMENTAL
The progress of reactions and the purity of the
isolated compounds were monitored by TLC on Silufol
UV-254 plates; spots were detected under UV light, by
treatment with iodine vapor, or by thermal decomposi-
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 10 2011

2-ACYL(AROYL)-1,1,3,3-TETRACYANOPROPENIDES: III.
1495
Compounds IIb–IIg were synthesized as described
above in a.
8.6 Hz), 8.47 br.s and 9.02 br.s (1H each, NH2). Mass
spectrum, m/z (Irel, %): 364 (4), 363 (3), 362 (19), 360
(15). Found, %: C 46.87; H 1.71; N 15.39.
C14H6BrClN4O. Calculated, %: C 46.50; H 1.67;
N 15.49. M 361.58.
2-Amino-6-chloro-4-(4-chlorobenzoyl)pyridine-
3,5-dicarbonitrile (IIb). Yield 67%, mp 238–240°C.
IR spectrum, ν, cm–1: 3204 (NH2), 2210 (C≡N), 1650
1
(C=O). H NMR spectrum, δ, ppm: 7.73 d (2H, Harom
,
2-Amino-6-bromo-4-(4-methylbenzoyl)pyridine-
3,5-dicarbonitrile (IIg). Yield 78%, mp 217–218°C.
IR spectrum, ν, cm–1: 3192 (NH2), 2240 (C≡N), 1660
3J = 6.1 Hz), 8.05 d (2H, Harom, J = 5.9 Hz), 8.49 br.s
and 9.00 br.s (1H each, NH2). Mass spectrum, m/z
(Irel, %): 320 (3), 319 (3), 318 (15), 317 (14), 316 (28).
Found, %: C 53.31; H 1.93; N 17.01. C14H6Cl2N4O.
Calculated, %: C 53.02; H 1.91; N 16.98. M 317.13.
3
1
(C=O). H NMR spectrum, δ, ppm: 2.35 s (3H, CH3),
3
7.15 m (2H, Harom, J = 8.3 Hz), 7.35 m (2H, Harom
,
3J = 8.2 Hz), 8.44 br.s and 8.97 br.s (1H each, NH2).
Mass spectrum, m/z (Irel, %): 342 (19), 340 (21).
Found, %: C 52.84; H 2.68; N 16.37. C15H9BrN4O.
Calculated, %: C 52.81; H 2.66; N 16.42. M 341.16.
2-Amino-6-chloro-4-(4-methylbenzoyl)pyridine-
3,5-dicarbonitrile (IIc). Yield 73%, mp 246–247°C
(decomp.). IR spectrum, ν, cm–1: 3201 (NH2), 2253
(C≡N), 1682 (C=O). 1H NMR spectrum, δ, ppm: 2.45 s
2-Amino-4-benzoyl-6-iodopyridine-3,5-dicarbo-
nitrile (IIh). a. A solution of 2.63 g (0.01 mol) of am-
monium 2-benzoyl-1,1,3,3-tetracyanopropenide in 5 ml
of butan-2-ol was heated to 60°C, 2 ml of concentrated
hydroiodic acid was added dropwise under stirring
over a period of 15 min, and the mixture was stirred
for 30 min at 70–75°C and poured into 100 ml of
boiling water. The precipitate was filtered off, washed
with diethyl ether, and recrystallized from methanol.
Yield 2.1 g (56%), decomposition point 173–175°C.
(3H, CH3), 7.46 d (2H, Harom, 3J = 8.1 Hz), 7.91 d (2H,
3
H
arom, J = 8.2 Hz), 8.45 br.s and 8.95 br.s (1H each,
NH2). Mass spectrum, m/z (Irel, %): 298 (9), 297 (4),
296 (28). Found, %: C 60.73; H 3.11; N 18.83.
C15H9ClN4O. Calculated, %: 60.72; H 3.06; N 18.88.
M 296.71.
2-Amino-6-chloro-4-pivaloylpyridine-3,5-dicar-
bonitrile (IId). Yield 84%, sublimes at 243–246°C,
mp 254–255°C (in a sealed capillary). IR spectrum, ν,
cm–1: 3222 (NH2), 2204 (C≡N), 1665 (C=O). 1H NMR
spectrum, δ, ppm: 1.05 s (9H, t-Bu), 8.41 br.s and
8.92 br.s (1H each, NH2). Mass spectrum, m/z (Irel, %):
264 (10), 263 (3), 262 (34). Found, %: C 54.81;
H 4.28; N 21.64. C12H11ClN4O. Calculated, %:
C 54.87; H 4.22; N 21.33. M 262.69.
IR spectrum, ν, cm–1: 3153 (NH2), 2201 (C≡N), 1664
1
(C=O). H NMR spectrum, δ, ppm: 7.65 t (2H, Harom
,
3J = 7.8 Hz), 7.84 t (1H, Harom, J = 7.4 Hz), 7.99 d
(2H, Harom, J = 7.3 Hz), 8.30 br.s and 9.89 br.s (1H
3
3
each, NH2). Mass spectrum, m/z (Irel, %): 375 (1), 374
(11). Found, %: C 44.98; H 1.92; N 14.83. C14H7IN4O.
Calculated, %: C 44.94; H 1.89; N 14.97. M 374.14.
2-Amino-4-benzoyl-6-bromopyridine-3,5-dicar-
bonitrile (IIe). Yield 2.6 g (71%), mp 231–232°C
(decomp.). IR spectrum, ν, cm–1: 3211 (NH2), 2221
(C≡N), 1664 (C=O). 1H NMR spectrum, δ, ppm: 7.66 t
b. A solution of 2.63 g (0.01 mol) of ammonium
2-benzoyl-1,1,3,3-tetracyanopropenide in 5 ml of
butan-2-ol was heated to 70–75°C, and gaseous hydro-
gen iodide was passed through the solution at a flow
rate of 0.5–1.0 ml/s over a period of 20 min. After
cooling, the precipitate was filtered off, washed with
20 ml of water, and recrystallized from dioxane.
3
3
(2H, Harom, J = 7.7 Hz), 7.85 t (1H, Harom, J =
3
7.6 Hz), 8.02 d (2H, Harom, J = 8.2 Hz), 8.46 br.s and
9.00 br.s (1H each, NH2). 13C NMR spectrum, δC, ppm:
86.41 (C3), 95.53 (C5), 113.03, 114.76 (5-CN, 3-CN),
129.69 (2C, Cm), 130.15 (2C, Co), 132.75 and 136.14
(Ci, Cp), 147.85 (C6), 157.55 (C4), 159.61 (C2), 190.21
(C=O). Mass spectrum, m/z (Irel, %): 328 (20), 326
(21). Found, %: C 51.48; H 2.19; N 17.07.
C14H7BrN4O. Calculated, %: C 51.40; H 2.16;
N 17.13. M 327.14.
Compounds IIi–IIk were synthesized as described
above for IIh according to method a.
2-Amino-4-(4-chlorobenzoyl)-6-iodopyridine-
3,5-dicarbonitrile (IIi). Yield 54%, mp 185–187°C
(decomp.). IR spectrum, ν, cm–1: 3203 (NH2), 2215
1
(C≡N), 1662 (C=O). H NMR spectrum, δ, ppm:
7.74 d (2H, Harom, 3J = 5.9 Hz), 8.06 d (2H, Harom, 3J =
5.9 Hz), 8.39 br.s and 8.89 br.s (1H each, NH2). Mass
spectrum, m/z (Irel, %): 410 (3), 408 (10). Found, %:
C 41.19; H 1.52; N 13.65. C14H6ClIN4O. Calculated,
%: C 41.15; H 1.48; N 13.71. M 408.58.
2-Amino-6-bromo-4-(4-chlorobenzoyl)pyridine-
3,5-dicarbonitrile (IIf). Yield 74%, mp 257–258°C
(decomp.). IR spectrum, ν, cm–1: 3230 (NH2), 2205
1
(C≡N), 1666 (C=O). H NMR spectrum, δ, ppm:
7.73 d (2H, Harom, 3J = 8.5 Hz), 8.06 d (2H, Harom, 3J =
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 10 2011

KARPOV et al.
1496
3
CH3), 7.31 d (2H, Harom, J = 8.0 Hz), 7.74 d (2H,
H
2-Amino-6-iodo-4-(4-methylbenzoyl)pyridine-
3
arom, J = 8.02 Hz), 10.46 br.s (2H, NH2). Mass spec-
3,5-dicarbonitrile (IIj). Yield 61%, mp 166–167°C
(decomp.). IR spectrum, ν, cm–1: 3213 (NH2), 2224
(C≡N), 1660 (C=O). 1H NMR spectrum, δ, ppm: 2.34 s
trum, m/z (Irel, %): 343 (2), 342 (16), 341 (3), 340 (17).
Found, %: C 52.91; H 2.72; N 16.31. C15H9BrN4O.
Calculated, %: C 52.81; H 2.66; N 16.42. M 341.16.
(3H, CH3), 7.18 d (2H, Harom, 3J = 7.8 Hz), 7.36 d (2H,
3
H
arom, J = 7.9 Hz), 8.45 br.s and 9.01 br.s (1H each,
2-(5-Amino-2-bromo-2-tert-butyl-4-cyano-2,3-
dihydrofuran-3-ylidene)malononitrile (IIId). Yield
65%, decomposition point 245–246°C. IR spectrum, ν,
cm–1: 3318, 3115 (NH2); 2253 (C≡N); 1663 (C=C).
1H NMR spectrum, δ, ppm: 1.23 s (9H, t-Bu), 10.49 s
and 10.53 s (1H each, NH2). Mass spectrum, m/z
(Irel, %): 309 (3), 308 (20), 307 (3), 306 (21). Found,
%: C 47.08; H 3.69; N 18.07. C12H11BrN4O. Calculat-
ed, %: C 46.93; H 3.61; N 18.24. M 307.15
NH2). Mass spectrum, m/z (Irel, %): 389 (2), 388 (13).
Found, %: C 46.45; H 2.37; N 14.38. C15H9IN4O. Cal-
culated, %: C 46.41; H 2.34; N 14.43. M 388.16.
2-Amino-6-iodo-4-pivaloylpyridine-3,5-dicarbo-
nitrile (IIk). Yield 74%, mp 182–183°C (decomp.). IR
spectrum, ν, cm–1: 3210 (NH2), 2198 (C≡N), 1671
1
(C=O). H NMR spectrum, δ, ppm: 1.28 s (9H, t-Bu),
8.31 br.s and 8.82 br.s (1H each, NH2). Mass spectrum,
m/z (Irel, %): 355 (2), 354 (18). Found, %: C 40.78;
H 3.17; N 15.78. C12H11IN4O. Calculated, %: C 40.70;
H 3.13; N 15.82. M 354.15.
Compounds IIIe–IIIg were synthesized in a similar
way by passing gaseous hydrogen chloride.
2-(5-Amino-2-chloro-4-cyano-2-phenyl-2,3-dihy-
drofuran-3-ylidene)malononitrile (IIIe). Yield
(74%), mp 150–151°C (decomp.) [2].
2-(5-Amino-2-bromo-4-cyano-2-phenyl-2,3-dihy-
drofuran-3-ylidene)malononitrile (IIIa). Gaseous
hydrobromic acid was slowly passed over a period
20 min (flow rate 0.5–1.0 ml/s) through a solution of
2.63 g (0.01 mol) of ammonium 2-benzoyl-1,1,3,3-
tetracyanopropenide in 10 ml of water, heated to 65–
70°C. The precipitate was filtered off, washed with
water, and recrystallized from methanol. Yield 2.22 g
(68%), decomposition point 239–241°C. IR spectrum,
ν, cm–1: 3290 (NH2), 2225 (C≡N), 1668 (C=C).
1H NMR spectrum, δ, ppm: 7.35–7.56 m (5H, Harom),
10.51 s (2H, NH2). Mass spectrum, m/z (Irel, %):
328 (16), 326 (17). Found, %: C 51.45; H 2.19;
N 17.04. C14H7BrN4O. Calculated, %: C 51.40;
H 2.16; N 17.13. M 327.14.
2-[5-Amino-2-(4-bromophenyl)-2-chloro-4-
cyano-2,3-dihydrofuran-3-ylidene]malononitrile
(IIIf). Yield 67%, mp 133–136°C (decomp.); pub-
lished data [2]: mp 135–136°C (decomp.).
2-[5-Amino-2-chloro-4-cyano-2-(4-methoxy-
phenyl)-2,3-dihydrofuran-3-ylidene]malononitrile
(IIIg). Yield 81%, mp 140–142°C (decomp.); pub-
lished data [2]: 141–142°C (decomp.).
2-(5-Amino-4-cyano-2-phenyl-2,3-dihydrofuran-
3-ylidene)malononitrile (IVa). a. A solution of 2.63 g
(0.01 mol) of ammonium 2-benzoyl-1,1,3,3-tetra-
cyanopropenide in 10 ml of water was heated to 65–
70°C, and 2.7 ml of 56% hydroiodic acid was added
dropwise under stirring over a period of 20 min. The
precipitate was filtered off, washed with 3 ml of
1% aqueous potassium iodide and with water, and
recrystallized from 1,4-dioxane. Yield 1.41 g (57%),
mp 263–264°C (decomp.). IR spectrum, ν, cm–1: 3318,
3115 (NH2); 2223 (C≡N); 1663 (C=C). 1H NMR spec-
trum, δ, ppm: 6.81 s (1H, CH), 7.41–7.52 m (5H, Ph),
10.07 s (2H, NH2). Mass spectrum, m/z (Irel, %): 249
(7), 248 (43). Found, %: C 67.89; H 3.31; N 22.43.
C14H8N4O. Calculated, %: C 67.74; H 3.25; N 22.57.
M 248.24.
Compounds IIIb–IIId were synthesized in a simi-
lar way.
2-[5-Amino-2-bromo-2-(4-chlorophenyl)-4-
cyano-2,3-dihydrofuran-3-ylidene]malononitrile
(IIIb). Yield 76%, decomposition point 246–248°C. IR
spectrum, ν, cm–1: 3290, 3124 (NH2); 2201 (C≡N);
1
1666 (C=C). H NMR spectrum, δ, ppm: 7.65 d (2H,
3
3
H
arom, J = 6.01 Hz), 7.74 d (2H, Harom, J = 6.0 Hz),
10.48 br.s (2H, NH2). Mass spectrum, m/z (Irel, %): 362
(26), 361 (15), 364 (5), 363 (3). Found, %: C 46.52;
H 1.71; N 15.43. C14H6BrClN4O. Calculated, %:
C 46.50; H 1.67; N 15.49. M 361.58.
b. A solution of 2.63 g (0.01 mol) of ammonium
2-benzoyl-1,1,3,3-tetracyanopropenide in 5 ml of
water was heated to 70–75°C, and gaseous hydrogen
iodide was passed through the solution over a period of
20 min at a flow rate of 1.5–2.0 ml/s. The mixture was
cooled, and the precipitate was filtered off, washed
2-[5-Amino-2-bromo-4-cyano-2-(4-methylphe-
nyl)-2,3-dihydrofuran-3-ylidene]malononitrile
(IIIc). Yield 59%, decomposition point 243–245°C. IR
spectrum, ν, cm–1: 3260, 3128 (NH2); 2215 (C≡N);
1
1665 (C=C). H NMR spectrum, δ, ppm: 2.41 s (3H,
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 10 2011

2-ACYL(AROYL)-1,1,3,3-TETRACYANOPROPENIDES: III.
1497
with 20 ml of water, and recrystallized from 1,4-di-
oxane. Yield 1.74 g (70%), mp 263–264°C (decomp.).
This study was performed in the framework of
a federal special-purpose program (state contract
no. 16.740.11.0160).
Compounds IVb and IVc were synthesized as de-
scribed for IVa according to method a.
REFERENCES
2-[5-Amino-2-(4-chlorophenyl)-4-cyano-2,3-dihy-
drofuran-3-ylidene]malononitrile (IVb). Yield 61%,
mp 266–268°C (decomp.). IR spectrum, ν, cm–1: 3321,
3113 (NH2); 2230 (C≡N); 1660 (C=C). 1H NMR spec-
trum, δ, ppm: 6.85 s (1H, CH), 7.47–7.50 m (2H,
Harom, J = 8.5 Hz), 7.53–7.56 m (2H, Harom, J =
8.5 Hz), 10.10 s (2H, NH2). Mass spectrum, m/z
(Irel, %): 284 (13), 283 (4), 282 (39). Found, %:
C 60.06; H 2.61; N 19.73. C14H7ClN4O. Calculated, %:
C 59.48; H 2.50; N 19.82. M 282.68.
1. Karpov, S.V., Kayukov, Ya.S., Bardasov, I.N., Er-
shov, O.V., Nasakin, O.E., and Kayukova, O.V., Russ. J.
Org. Chem., 2011, vol. 47, p. 1161.
2. Bardasov, I.N., Kayukova, O.V., Kayukov, Ya.S., Er-
shov, O.V., Nasakin, O.E., and Tafeenko, V.A., Russ. J.
Org. Chem., 2009, vol. 45, 1325.
3. Karpov, S.V., Kayukov, Ya.S., Bardasov, I.N., Kayuko-
va, O.V., Ershov, O.V., and Nasakin, O.E., Russ. J. Org.
Chem., 2011, vol. 47, p. 405.
4. Duindam, A., Lishinsky, V.L., and Sikkama, D.J., Synth.
Commun., 1993, vol. 23, p. 2605.
3
3
2-[5-Amino-4-cyano-2-(4-methylphenyl)-2,3-di-
hydrofuran-3-ylidene]malononitrile (IVc). Yield
64%, mp 249–251°C (decomp.). IR spectrum, ν, cm–1:
3327, 3115 (NH2); 2221 (C≡N); 1664 (C=C). 1H NMR
spectrum, δ, ppm: 2.45 s (3H, CH3), 6.79 s (1H, CH),
7.43 d (2H, Harom, 3J = 7.9 Hz), 7.47 d (2H, Harom, 3J =
8.0 Hz), 10.09 s (2H, NH2). Mass spectrum, m/z
(Irel, %): 263 (7), 262 (40). Found, %: C 68.71; H 3.91;
N 21.31 C15H10N4O. Calculated, %: C 68.69; H 3.84;
N 21.36. M 262.27.
5. Mittelbach, M. and Junek, H., J. Heterocycl. Chem.,
1982, vol. 19, p. 1021.
6. Granik, V.G., Grizik, S.I., Solov’eva, N.P., Anisimo-
va, O.S., and Sheinker, Yu.N., Zh. Org. Khim., 1984,
vol. 20, p. 673.
7. Vieth, S., Gruendemann, E., Jaehnisch, K., Winter, G.,
and Reck, G., Monatsh. Chem., 1991, vol. 122, p. 1035.
8. Kantehner, W. and Greiner, U., Justus Liebigs Ann.
Chem., 1990, p. 965.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 10 2011