Oxidative coupling of substituted 1,2,3,4,4a,5-hexahydro-13H-benzimidazo[2, 1-j]quinolines with Methylene-active derivatives of carboxylic acids

Article abstract of DOI:10.1134/S107042800908017X

The oxidative coupling of substituted 1,2,3,4,4a,5-hexahydro-13H- benzimidazo[2,1-j]quinolines with methylene-active derivatives of carboxylic acids led to the formation of p-methylenequinone imines of the mentioned series; in some events the reaction was

Full text of DOI:10.1134/S107042800908017X

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2009, Vol. 45, No. 8, pp. 1214−1218. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © O.Yu. Slabko, N.V. Ageenko, V.A. Kaminskii, 2009, published in Zhurnal Organicheskoi Khimii, 2009, Vol. 45, No. 8, pp. 1223−
1227.
Oxidative Coupling of Substituted
1,2,3,4,4a,5-Hexahydro-13H-benzimidazo[2,1-j]quinolines
with Methylene-Active Derivatives of Carboxylic Acids
O. Yu. Slabkoa, N. V. Ageenkoa,b, and V. A. Kaminskiia
aFar-Eastern State University, Vladivostok, 690600 Russia
e-mail: slabko@chem.dvgu.ru
bZhirmunskii Institute of Marine Biology, Far-Eastern Division, Russian Academy of Sciences,
Vladivostok, Russia
Received October 27, 2008
Abstract—The oxidative coupling of substituted 1,2,3,4,4a,5-hexahydro-13H-benzimidazo[2,1-j]quinolines with
methylene-active derivatives of carboxylic acids led to the formation of p-methylenequinone imines of the mentioned
series; in some events the reaction was accompanied with a hydrolytic cleavage of the exocyclic fragment.
DOI: 10.1134/S107042800908017X
lines Ia and Ib with certain methylene-active functional
derivatives of carboxylic acids aiming at preparation of
water-soluble methylenequinone imines arising further by
hydrolytic transformations. We selected as reagents
diethyl malonate and malonodiamide, ethyl nitroacetate,
and cyanoacetic acid hydrazide; at the use of the latter
compound a problem of the regioselectivity existed for
the reagent possessed both C- and N-nucleophilic sites.
Heterocyclic p-methylenequinone imines belong to one
among the least investigated types of quinoid compounds
presumably because they are difficultly available due to
the lack of general and convenient preparation methods.
Methylenequinone imines are known based on phen(oxa,
thia)-azines obtained either by oxidative condensation with
CH-acids where the first stage consists in the formation
of ortho-quinoid cations of phen(oxa, thia)-azinium [1],
or as a result of molecular rearrangements of products
of the nucleophilic substitution in the aromatic ring of
phenoxazinones [2] or ion-radical betaines based on
phenazine [3]. Also methylenequinone imines were
obtained by oxidation of the products of nucleophilic
addition of C-nucleophiles to the ortho-quinoid ring of
2H-benzimidazoles [4] and by oxidative condensation of
1-naphthylmalononitrile with aromatic amines [5]. All
the mentioned preparation procedures provided the target
compounds in poor yields.
We established that the main result of the oxidative
coupling of compounds Ia and Ib with diethyl malonate,
malonodiamide, and ethyl nitroacetate (V) in the presence
of MnO2 was the formation in good yield of p-methyl-
enequinone imines, derivatives of 1,2,3,4,4a,5-hexahydro-
10H-benzimidazo[2,1-j]quinoline (compounds IIa, IIb,
IIIa, IIIb, VIIa, and VIIb); in reaction with the latter
compound formed also in a minor amount the product of
its hydrolytic cleavage (compound IXb). Compounds
VIIa, VIIb, and IXb are first examples of methylene-
quinone imine having as an exocyclic fragment derivatives
of nitroacetic acid. In the reaction of compounds Ia and
Ib with malonodiamide alongside the main products we
observed the formation in substantial amounts of products
of a competing oxidation reaction, quinone monoimines
IVa and IVb, which had been described before [7]. The
formation of the latter products was caused presumably
by the low solubility of the reagents preventing the
presence of its excess in the reaction mixture. In neither
We formerly reported [6] on a simple and convenient
procedure for the synthesis of heterocyclic methylene-
quinone imines by an oxidative coupling of substituted
pyrido[1,2-a]-benzimidazoles with CH-acid nucleophiles;
the main attention was drawn to the 1,3-dicarbonyl
reagents. In this study we carried out a purposeful
investigation of an oxidative coupling of substituted
1,2,3,4,4a,5-hexahydro-13H-benzimidazo[2,1-j]-quino-
1214

OXIDATIVE COUPLING
1215
O
X
O
O
N
X
R3
R3
R3
9
O
O
10 11
12
R2
R1
R2
R1
7
R2
8
N
N
X
X
N
6
1 N13
NH
[O]
R1
5
2
4
COOEt
[O]
CN
O
3
Ia, Ib
IIa, IIb, IIIa, IIIb
IVa, IVb
Y
COOEt
Y
COOH
R3
R3
Y
X
R2
R1
R2
R1
V, VI
N
N
N
N
[O]
VIIa, VIIb, VIIIa, VIIIb
IXb, Xa, Xb
R1 = H, R2,R3 = (CH2)4 (a); R1 = R3 = Ph, R2 = H (b); X = OEt (II, V), NH2 (III), NHNH2 (VI); Y= NO2 (V, VII, IX), CN (VI, VIII,
X).
soluble in a water-alkaline medium.
of the other reactions the quinone monoimines formation
was observed.
IR spectra of all compounds obtained contain the
absorption bands of vibrations of C=C and C=N bonds in
the quinoid structure, and also of the functional groups of
The oxidative coupling of substrates Ia and Ib with
cyanoacetic acid hydrazide (VI) in ethanol occurred
exclusively at the CH-acid site of the reagent: mixtures
were obtained that after chromatographic separation
afforded p-methylenequinone imines lacking the
hydrazine fragment and consisting of comparable
quantities of alcoholysis (compounds VIIIa and VIIIb)
and hydrolysis (compounds Xa and Xb) products. These
results are in agreement with the data of review [8] on
the oxidative transformations of phenylhydrazides into the
corresponding carboxylic acids in the presence of MnO2;
no methylenequinones with a hydrazide groups in an
exocyclic fragment have been described indirectly
confirming that their preparation in oxidative conditions
is impossible. Methylenequinone imines VIIIa and VIIIb
were also prepared by an independent synthesis: by the
coupling of substrates Ia and Ib with ethyl cyanoacetate
in the presence of MnO2 (the reaction products were
identified by TLC, melting points, and IR spectra).
1
the exocyclic fragment; H NMR spectra contain the
signals of protons H9, H11, H12 proving the para-quinoid
structure of the products. In the spectra of compounds
IIa, IIb, VIIa, VIIb, VIIIa, and VIIIb ethoxy group
signals are present, and in the spectra of compounds
IXb, Xa, and Xb, those of the OH from the carboxy
group. In the spectrum of compound IIIb four one-proton
broadened singlets were observed disappearing at the
addition of deuteromethanol and belonging to non-
equivalent protons of the primary amino groups, whereas
in the spectrum of compound IIIa the proton signals of
both amino groups coalesce into one four-proton broaden-
ed singlet. This difference in the spectra of related
methylenequinone imines may be caused by the higher
inversion barrier with respect the exocyclic C10=C2 bond
due to the intramolecular charge transfer in the system
N8–C8a=C9–C10=C2 of compound IIIb as compared to
compound IIIa. The double sets of signals in different
integral ratios of the protons of the quinoid system, ethoxy
All compounds obtained are colored and relatively
stable (compounds VIIa and VIIb are an exception for
they are labile under the conditions of the preparative
chromatography). Compounds IXb, Xa, and Xb are well
1
fragments and some other protons observed in the H
NMR spectra of compounds VIIIa, VIIIb, Xa, and Xb
we attribute to the presumable ð-diastereoisomerism with
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 8 2009

SLABKO et al.
1216
respect to the double C10=C2 bond with the prevalence
of the Z-isomer [the ratio Z/E 3:1 (VIIIa), 3:2 (VIIIb),
4:1 (Xa), 3:2 (Xb)]; a similar effect has been observed
formerly in the obtained methylenequinone imines [6]. In
the spectrum of the oxidative coupling product with ethyl
nitroacetate VIIb on the contrary prevailed the Ε-isomer
(the ratio Z/E 1:2), and compounds VIIa and IXb were
completely in the thermodynamically more stable Ε-form;
the signals assignment was carried out by the comparison
with the spectral data for the Z/E-isomers of the previous-
ly obtained product of the oxidative coupling with
nitromethane [6]. In the 1H NMR spectrum of compound
IIb four quartets were observed from the methylene
groups of the ethoxy fragment in the ratio 1:1, whereas
the methyl groups gave rise to only two triplets; this was
apparently due to the existence of sufficiently stable
conformers with respect to the CH2–OCO bond. In the
spectra of compounds IIa, VIIa, VIIIa, and Xa from
the multiplet of aliphatic protons a one-proton multiplet
separated located downfield and belonging to the allyl
equatorial proton H1' of the fused cyclohexene ring that
suffered deshielding spatial influence of the electron-
acceptor substituents in the exocyclic fragment (as
suggested by models). The mass values of pseudo-
molecular ions in the mass spectra of all compounds
synthesized obtained by the chemical ionization were in
agreement with the calculated figures.
UV-254 and Sorbfil plates, eluents petroleum ether–ethyl
acetate, ethyl acetate–acetone. The products mixtures
were separated and the products were purified by
preparative TLC on 25 × 30 cm plates with aluminum
oxide of the II Brockmann grade or with silica gel, the
layer thickness 1.5 mm, single charge 0.25 g.
All compounds were synthesized by the general
procedure, only the separation and purification differed.
Commercially available reagents (Aldrich, Fluka) were
used without additional purification.
General procedure. To a solution of 1.0 mmol of com-
pounds Ia or Ib and 2.0 mmol of a reagent (1.1 mmol of
reagent VI) in 30–40 ml of acetone (DMF for compounds
IIIa and IIIb, ethanol for VIIIa, VIIIb, Xa, and Xb)
was added at stirring 10–12 mmol of MnO2, the reaction
mixture was stirred for 1 h at room temperature
(compounds IIa, IIIa, and IIIb), 2 h (compounds IIb,
VIIa, VIIb, and IXb), 5 h (compounds VIIIb and Xb),
8 h (compounds VIIIa and Xa) till complete consumption
of the initial compound (TLC monitoring), MnO2 was
filtered off and washed with the solvent used in the
reaction. The filtrates of all compounds obtained were
diluted with water to 2–3 fold volume, saturated with NaCl
(compounds IIIa and IIIb) or Na2CO3 (compounds IIa
and IIb) till a precipitate formed. The latter was subjected
to preparative TLC on aluminum oxide using as eluent
petroleum ether–ethyl acetate, 5:1, for compounds IIa,
IIb, VIIb, IXb, 3:1, for compound IIIa, 2:1, for
compounds VIIIa, VIIIb, Xa, Xb; or on silica gel using
as eluent petroleum ether–ethyl acetate, 3:1, for
compound VIIa, ethyl acetate–acetone, 5:1, for compound
IIIb.
EXPERIMENTAL
IR spectra were recorded on spectrophotometers
Specord 75IR and Spectrum BX-II from solutions in
1
CH2Cl2 and pellets with KBr. H NMR spectra were
Diethyl
(6,7-tetramethylene-1,2,3,4,4a,5-
registered on a spectrometer BrukerAC-250 at operating
frequency 250 MHz, internal reference TMS, solvent
CDCl3. Elemental analysis was carried out on a CHN-
analyzer Flash EA 1112 CHN/MAS200.
hexahydro-10H-benzimidazo[2,1-j]quinolin-10-
ylidene)-malonate (IIa). Yield 78%, mp. 96–98°C. IR
spectrum, ν, cm–1: 1698, 1675 (C=O), 1636 (C6=C7),
1615, 1580, 1498 (C=N, C=Cquin). 1H NMR spectrum, δ,
ppm: 1.30 t (3H, CH3, J 7.2 Hz), 1.33 t (3H, CH3,
J 7.2 Hz), 1.45–2.40 m (18H), 2.73 m (1H, H1eqiov.), 4.23 q
(2H, OCH2, J 7.2 Hz), 4.26 q (2H, OCH2, J 7.2 Hz),
6.78 d (1H, H9, J 2.0 Hz), 6.90 d (1H, H12, J 10.0 Hz),
7.55 d.d (1H, H11, J 10.0, 2.0 Hz). Found, %: C 71.32;
H 7.06; N 6.68. [M + H]+ 437. C26H32N2O4. Calculated,
%: C 71.53; H 7.39; N 6.42. M 436.54.
The analysis by the method HPLC-MS was performed
on an instrument HP 1100 LC/MSD, column Hypersil
ODS (4×125 mm), mobile phase 2-propanol–water, 60 :
40, flow rate 0.3 ml/min, temperature 55°C; (a) diode
matrix, (b) direct admission into the ion source. The
conditions of recording mass spectrum: source APCI,
positive polarity (negative for compound IXb), voltage
on the fragmentor 70V.
Diethyl (5,7-diphenyl-1,2,3,4,4a,5-hexahydro-
10H-benzimidazo[2,1-j]quinolin-10-ylidene)-
malonate (IIb). Yield 85%, mp. 124–126°C. IR spec-
trum, ν, cm–1: 1709, 1684 (C=O), 1642 (C6=C7), 1619,
1582, 1504 (C=N, C=Cquin). 1H NMR spectrum, δ, ppm:
The melting points of compounds btained were
measured in a capillary and on a Bo¸tius heating block.
The reaction course was monitored and the homogeneity
of compounds obtained was checked by TLC on Silufol
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 8 2009

OXIDATIVE COUPLING
1217
1.15 t (3H, CH3, J 7.2 Hz), 1.25 t (3H, CH3, J 7.2 Hz),
1.45–2.25 m (9H), 3.83 d.d (1H, H5, J 10.0, 3.2 Hz),
3.87 q (2H, OCH2, J 7.1 Hz), 3.94 q (2H, OCH2,
J 7.1 Hz), 4.19 q (2H, OCH2, J 7.1 Hz), 4.21 q (2H,
OCH2, J 7.1 Hz), 5.06 d (1H, H9, J 1.7 Hz), 5.42 d (1H,
H6, J 3.2 Hz), 6.92 d (1H, H12, J 10.0 Hz), 7.15–7.53 m
(8H, ArH), 7.90 m (1H, ArH), 7.92 m (1H, ArH),
8.03 d.d (1H, H11, J 10.0, 1.7 Hz). Found, %: C 76.69;
H 6.22; N 5.38. [M + H]+ 535. C34H34N2O4. Calculated,
%: C 76.38; H 6.41; N 5.24. M 534.65.
spectrum, δ, ppm (Z/E 1:2): 1.15 t (3H, CH3, J 7.2 Hz,
Z-isomer), 1.28 t (3H, CH3, J 7.2 Hz, Ε-isomer), 1.45–
2.30 m (9H), 3.87 d.d (1H, H5, J 10.5, 3.0 Hz), 4.05 q
(2H, OCH2, J 7.2 Hz, Z-isomer), 4.28 q (2H, OCH2,
J 7.2 Hz, Ε-isomer), 4.98 d (1H, H9, J 1.8 Hz, Ε-isomer),
5.52 d (1H, H6, J 3.0 Hz), 5.65 d (1H, H9, J 1.5 Hz, Z-iso-
mer), 7.04 d (1H, H12, J 10.0 Hz), 7.20–7.50 m (10H,
C6H5), 8.00 d. d (1H, H11, J 10.0, 1.8 Hz, Ε-isomer).
Found, %: C 73.39; H 5.88; N 8.11. [M + H]+ 508.
C31H29N3O4. Calculated, %: C 73.35; H 5.76; N 8.28.
M 507.58.
2-(6,7-Tetramethylene-1,2,3,4,4a,5-hexahydro-
10H-benzimidazo[2,1-j]quinolin-10-ylidene)-malon-
amide (IIIa). Yield 74%, mp. 202–204°C. IR spectrum,
ν, cm–1: 3481, 3401, 3358 (NH2), 1653 (C=O), 1637
(C6=C7), 1600, 1538 (C=N, C=Cquin). 1H NMR spectrum,
δ, ppm: 1.40–2.50 m (19H), 6.38 d (1H, H9, J 1.7 Hz),
6.83 d (1H, H12, J 10.0 Hz), 7.45 br.s (4H, NH2),
7.54 d.d (1H, H11, J 10.0, 1.7 Hz). Found, %: C 70.10;
H 7.14; N 14.73. [M + H]+ 379. C22H26N4O2. Calculated,
%: C 69.82; H 6.92; N 14.80. M 378.47.
Ethyl 2-(6,7-tetramethylene-1,2,3,4,4a,5-hexa-
hydro-10H-benzimidazo[2,1-j]quinolin-10-ylidene)-
(cyano)acetate (VIIIa). Yield 43%, mp. 168–170°C.
IR spectrum, ν, cm–1: 2197 (CN), 1684 (C=O), 1654
1
(C6=C7), 1621, 1564, 1482 (C=N, C=Cquin). H NMR
spectrum, δ, ppm (Z/E 3:1): 1.35 t (3H, CH3, J 7.2 Hz),
1.55–2.40 m (18H), 2.80 m (1H, H1equiv), 4.26 q (2H,
OCH2, J 7.2 Hz), 6.42 d (1H, H9, J 1.7 Hz, Ε-isomer),
7.01 d (1H, H12, J 10.0 Hz, Ε-isomer), 7.07 d (1H, H12,
J 10.0 Hz, Z-isomer), 7.58 d.d (1H, H11, J 10.0, 1.7 Hz,
Z-isomer), 7.73 d (1H, H9, J 1.7 Hz, Z-isomer), 8.77 d.d
(1H, H11, J 10.0, 1.7 Hz, E-isomer). Found, %: C 74.22;
H 7.17; N 10.75. [M + H]+ 390. C24H27N3O2. Calculated,
%: C 74.01; H 6.99; N 10.79. M 389.49.
2-(5,7-Diphenyl-1,2,3,4,4a,5-hexahydro-10H-
benzimidazo[2,1-j]quinolin-10-ylidene)malonamide
(IIIb). Yield 62%, mp. 242–244°C. IR spectrum, ν, cm–
1: 3497, 3413, 3366 (NH2), 1656 (C=O), 1642 (C6=C7),
1598, 1570, 1501 (C=N, C=Cquin). 1H NMR spectrum, δ,
ppm: 1.50–2.20 m (9H), 3.83 d.d (1H, H5, J 10.1,
3.0 Hz), 5.20 br.s (1H, NH), 5.22 d (1H, H9, J 1.5 Hz),
5.42 d (1H, H6, J 3.0 Hz), 5.51 br.s (1H, NH), 5.68 br.s
(1H, NH), 6.82 br.s (1H, NH), 6.91 d (1H, H12, J 10.1
Hz), 7.20–7.45 m (10H, C6H5), 7.93 d.d (1H, H11, J 10.1,
1.5 Hz). Found, %: C 75.44; H 6.09; N 11.56. [M + H]+
477. C30H28N4O2. Calculated, %: C 75.61; H 5.92;
N 11.76. M 476.57.
Ethyl 2-(5,7-diphenyl-1,2,3,4,4a,5-hexahydro-
10H-benzimidazo[2,1-j]quinolin-10-ylidene)(cyano)-
acetate (VIIIb). Yield 41%, mp. 177–179°C. IR spec-
trum, ν, cm–1: 2195 (CN), 1699 (C=O), 1643 (C6=C7),
1619, 1569, 1498 (C=N, C=Cquin.). 1H NMR spectrum, δ,
ppm (Z/E 3:2): 1.25 t (3H, CH3, J 7.1 Hz), 1.50–2.40 m
(9H), 3.47 q (2H, OCH2, J 7.1 Hz), 3.89 m (1H, H5),
5.56 d (1H, H6, J 3.0 Hz, Ε-isomer), 5.58 d (1H, H6,
J 3.0 Hz, Z-isomer), 6.84 d (1H, H9, J 1.6 Hz, Ε-isomer),
6.91 d (1H, H9, J 1.6 Hz, Z-isomer), 7.16 d (1H, H12,
J 10.0 Hz, Z-isomer), 7.19–7.55 m (10H, C6H5), 7.57 d.d
(1H, H11, J 10.0, 1.6 Hz, Z-isomer), 8.85 d.d (1H, H11,
J 10.0, 1.6 Hz, E-isomer). Found, %: C 79.08; H 6.28;
N 8.53. [M + H]+ 488. C32H29N3O2. Calculated, %:
C 78.82; H 5.99; N 8.62. M 487.59.
Ethyl (2Ε)-(6,7-tetramethylene-1,2,3,4,4a,5-
hexahydro-10H-benzimidazo[2,1-j]quinolin-10-
ylidene)(nitro)acetate (VIIa). Yield 54%, mp. 129–
131°C. IR spectrum, ν, cm–1: 1691 (C=O), 1666 (C6=C7),
1627, 1573, 1520 (C=N, C=Cquin), 1498, 1352 (NO2).
1H NMR spectrum, δ, ppm: 1.34 t (3H, CH3, J 7.2 Hz),
1.55–2.40 m (18H), 2.70 m (1H, H1e ), 4.29 q (2H, OCH2,
J 7.2 Hz), 6.56 br.s (1H, H9), 7.12 d (1H, H12, J 9.5 Hz),
7.75 d (1H, H11, J 9.5 Hz). Found, %: C 67.69; H 6.73;
N 10.18. [M + H]+ 410. C23H27N3O4. Calculated, %:
C 67.46; H 6.65; N 10.26. M 409.48.
(2Ε)-(5,7-Diphenyl-1,2,3,4,4a,5-hexahydro-10H-
benzimidazo[2,1-j]quinolin-10-ylidene)(nitro)-acetic
acid (IXb). Yield 9%, mp. 232–234°C. IR spectrum, ν,
cm–1: 3298, 1723 (COOH), 1644 (C6=C7), 1621, 1592,
1
Ethyl (5,7-diphenyl-1,2,3,4,4a,5-hexahydro-10H-
benzimidazo[2,1-j]quinolin-10-ylidene)(nitro)-
acetate (VIIb). Yield 75%, mp. 194–196°C. IR spec-
trum, ν, cm–1: 1700 (C=O), 1645 (C6=C7), 1624, 1580,
1516 (C=N, C=Cquin), 1502, 1327 (NO2). H NMR
spectrum, δ, ppm: 1.15–2.20 m (9H), 3.78 d.d (1H, H5,
J 10.5, 3.0 Hz), 5.32 d (1H, H6, J 3.0 Hz), 6.05 d (1H, H9,
J 1.8 Hz), 6.34 d (1H, H12, J 10.0 Hz), 7.20–7.50 m (10H,
C6H5), 7.58 d.d (1H, H11, J 10.0, 1.8 Hz), 8.51 s (1H,
1
1518 (C=N, C=Cquin), 1508, 1363 (NO2). H NMR
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 8 2009

SLABKO et al.
1218
COOH). Found, %: C 72.89; H 5.36; N 8.51. [M – H]–
478. C29H25N3O4. Calculated, %: C 72.64; H 5.25; N 8.76.
M 479.53.
H12, J 10.0 Hz, E-isomer), 7.09 d (1H, H12, J 10.0 Hz,
Z-isomer), 7.17–7.52 m (10H, C6H5), 7.55 d.d (1H, H11,
J 10.0, 1.7 Hz, Z-isomer), 8.67 d.d (1H, H11, J 10.0,
1.7 Hz, E-isomer). Found, %: C 78.65; H 5.39; N 9.11.
[M + H]+ 460. C30H25N3O2. Calculated, %: C 78.41;
H 5.48; N 9.14. M 459.54.
2-(6,7-Tetramethylene-1,2,3,4,4a,5-hexahydro-
10H-benzimidazo[2,1-j]quinolin-10-ylidene)-
(cyano)acetic acid (Xa). Yield 54%, mp. >300°C
(decomp.). IR spectrum, ν, cm–1: 3452, 1724 (COOH),
2184 (CN), 1653 (C6=C7), 1618, 1583, 1561 (C=N,
REFERENCES
1
C=Cquin). H NMR spectrum, δ, ppm (Z/E 4:1): 1.20–
1. Daneke, J. and Wanzlick, H.-W., Lieb. Ann., 1970, vol. 740,
p. 52; Rudenko, V.M., Il’chenko, A.Ya., and Rozum, Yu.S.,
Dopov. Akad. Nauk URSR, Ser. B, 1970, vol. 32, p. 159;
Bespalov, B.P., Khim. Geterotsikl. Soedin., 1985, p. 326.
2. Vysokov, V.I.,Afanas’eva, G.B., and Chupakhin, O.N., Khim.
Geterotsikl. Soedin., 1988, p. 538.
2.45 m (18H), 2.92 m (1H, H1equiv), 6.29 d (1H, H9,
J 1.5 Hz, Ε-isomer), 7.14 d (1H, H12, J 10.0 Hz, Z-isomer),
7.15 d (1H, H12, J 10.0 Hz, Ε-isomer), 7.44 d.d (1H, H11,
J 10.0, 1.5 Hz, Z-isomer), 7.65 br.s (1H, COOH, Z-iso-
mer), 7.98 d (1H, H9, J 1.5 Hz, Z-isomer), 8.79 br.s (1H,
COOH, Ε-isomer), 8.98 d.d (1H, H11, J 10.0, 1.5 Hz,
E-isomer). Found, %: C 73.28; H 6.53; N 11.52. [M +
H]+ 362. C22H23N3O2. Calculated, %: C 73.11; H 6.41;
N 11.63. M 361.44.
3. Clark-Lewis, J.W., Taylor, M.R., and Westphalen, J., Aust. J.
Chem. Soc., 1979, vol. 32, p. 1943.
4. Davies, K.E., Domany, G.E., Farhat, M., Herbert, J.A.L.,
Jefferson, A.M., Guttierrez, M.M.A., and Suschitzky, H.,
J. Chem. Soc., Perkin Trans. 1, 1984, p. 2465; Konwar, D.,
and Boruah, R.C., Indian J. Chem., 1989, no. 28B, p. 344.
5. Kubo, Y., Kuwana, M., Yoshida, K., Tomotake, Y., Matsuza-
ki, T., and Maeda, S., J. Chem. Soc. Chem. Commun., 1989,
p. 35.
6. Slabko, O.Yu., Mezhennaya, L.V., Kaminskii, V.A., and
Tilichenko, M.N., Khim. Geterotsikl. Soedin., 1990, p. 779.
7. Kaminskii, V.A., Slabko, O.Yu., and Tilichenko, M.N., Khim.
Geterotsikl. Soedin., 1988, p. 793.
2-(5,7-Diphenyl-1,2,3,4,4a,5-hexahydro-10H-
benzimidazo[2,1-j]quinolin-10-ylidene)(cyano)-
acetic acid (Xb). Yield 56%, mp. >300°C (decomp.). IR
spectrum, ν, cm–1: 3185, 1715 (COOH), 2189 (CN), 1645
(C6=C7), 1615, 1579, 1535 (C=N, C=Cquin). 1H NMR
spectrum, δ, ppm (Z/E 3:2): 1.45–2.30 m (9H), 3.87 m
(1H, H5), 5.32 d (1H, H9, J 1.7 Hz, Ε-isomer), 5.55 d (1H,
H6, J 3.4 Hz, Ε-isomer), 5.57 d (1H, H6, J 3.4 Hz, Z-iso-
mer), 6.51 d (1H, H9, J 1.7 Hz, Z-isomer), 7.03 d (1H,
8. Fatiadi,A.J., Synthesis, 1976, vol. 3, p. 133.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 8 2009