Synthesis of new spiro compounds proceeding from 11H-Indeno[1,2-b]quinoxalin-2-one

Article abstract of DOI:10.1134/S1070428015050164

Reaction of 11H-indeno[1,2-b]quinoxalin-2-one with semi(thiosemi)carbazides in ethanol resulted in semi(thiosemi)carbazones which at boiling in acetic anhydride underwent cylization yielding N-{3′-acetyl-3′H-spiro[indeno[1,2-b]quinoxalin-11,2′-[1,3,4]oxa(

Full text of DOI:10.1134/S1070428015050164

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2015, Vol. 51, No. 5, pp. 674–679. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © A.V. Velikorodov, N.N. Stepkina, E.A. Shustova, V.A. Ionova, 2015, published in Zhurnal Organicheskoi Khimii, 2015, Vol. 51,
No. 5, pp. 693–697.
Synthesis of New Spiro Compounds Proceeding
from 11Н-Indeno[1,2-b]quinoxalin-2-one
A. V. Velikorodov, N. N. Stepkina, E. A. Shustova, and V. A. Ionova
Astrakhan State University, pl. Shaumyana 1, Astrakhan, 414000 Russia
e-mail: avelikorodov@mail.ru
Received January 16, 2015
Abstract—Reaction of 11Н-indeno[1,2-b]quinoxalin-2-one with semi(thiosemi)carbazides in ethanol resulted
in semi(thiosemi)carbazones which at boiling in acetic anhydride underwent cylization yielding N-{3'-acetyl-
3'Н-spiro[indeno[1,2-b]quinoxalin- 11,2'-[1,3,4]oxa(thia)diazol]-5'-yl}acetamides. Aldol crotonic condensation
of 11Н-indeno[1,2-b]quinoxalin-2-one with methyl N-(4-acetylphenyl)carbamate afforded the corresponding
chalcone that at boiling in anhydrous ethanol with hydrazine hydrate for 1 h formed a spiro compound with a
pyrazole ring. Five-component condensation of ninhydrin, 1,2-phenylenediamine, sarcosine, malononitrile (or
ethyl cyanoacetate), and 4-formylphenyl N-phenylcarbamate in a mixture EtOH – [bmim]Br led to the
formation of 4-{3',3'-dicyano(or 3'-ethoxycarbonyl-3'-cyano)-1'-methylspiro[indeno[1,2-b]quinoxaline-11,2'-
pyrrolidin]-4'-yl}phenyl N-phenylcarbamates.
DOI: 10.1134/S1070428015050164
11Н-Indeno[1,2-b]quinoxalin-2-one 1 is widely
used for preparation of diverse derivatives exhibiting a
wide range of biological activity. Its oxime is a
noncytotoxic inhibitor of inflammatory cytokine and of
production of nitrogen monoxide [1]. Schiff bases
obtained from the 11Н-indeno[1,2-b]quinoxalin-2-one
are highly cytotoxic and possess antiviral activity [2].
Spiro compounds with the 11Н-indeno[1,2-b]-
quinoxaline fragment are of practical interest.
Chalcones preparation by aldol crotonic condensation
of 11Н-indeno-[1,2-b]quinoxalin-2-one with aceto-
phenones was described and their transformation into
spiro compounds with cyclopropane and pyrazole rings
was investigated [3, 4]. The synthetic methods for
derivatives of indeno[1,2-b]quinoxaline spiro-jointed
with other heterocyclic fragments are insufficiently
developed.
Boiling of equimolar quantities of semi(thiosemi)-
carbazides with compound 1 in ethanol afforded semi-
(thiosemi)carbazones of 11Н-indeno[1,2-b]quinoxalin-
2-one 2 and 3 in 95–97% yields. The structure and the
composition of compounds 2 and 3 was proved by IR
spectra and elemental analyses (Scheme 1).
Semi(thiosemi)carbazones of cyclic ketones are
known to by capable of heterocyclization with the
formation of spiro compounds [5]. We explored the
possibility to prepare new spiro compounds from semi-
Scheme 1.
X
H2N
HN
O
H
N
N
NH2
H2N
N
X
N
Δ
EtOH,
N
N
1
2, 3
X = O (2), S (3).
674

SYNTHESIS OF NEW SPIRO COMPOUNDS PROCEEDING FROM
675
Scheme 2.
X
O
H2N
NHCOMe
N
HN
Me
N
N
X
Ac2O, Δ
N
N
N
N
2, 3
4, 5
X = O (2, 4), S (3, 5).
Scheme 3.
N
COCH3
N
N
1. EtOH, Et2NH, Δ
2. AcOH, HCl, Δ
+
O
N
NHCO2CH3
O
NHCO2CH3
1
6
7
(thiosemi)carbazones 2 and 3. At boiling in acetic
anhydride for 4 h they suffer cyclization furnishing N-
(3'-acetyl-3'Н-spiro[indeno[1,2-b]quinoxalin-11,2'-
[1,3,4]-oxadiazol]-5'-yl)acetamide 4 and N-(3'-acetyl-
3'Н-spiro[indeno[1,2-b]quinoxaline-11,2'-[1,3,4]-
thiadiazol]-5'-yl)acetamide 5 in 89 and 88% yield
respectively (Scheme 2).
phenyl)carbamate 6 in anhydrous ethanol in the
presence of diethylamine followed by heating in
glacial acetic acid in the presence of hydrochloric acid
resulted in methyl (E)-N-{4-[2-(11Н-indeno-[2,1-b]-
quinoxalin-11-ylidene)acetyl]phenyl}carbamate 7 in
90% yield (Scheme 3).
Е-Configuration of chalcone 7 was confirmed by
the appearance in the downfield region (δ 7.70 ppm) of
a singlet signal belonging to the proton of the
conjugated double bond in keeping with the published
data for the other chalcones of E-configuration [6].
The structure of compounds 4 and 5 was proved by
1
IR, Н, 13С NMR spectra and by elemental analyses.
1Н NMR spectra of spiro compounds 4 and 5 alongside
the proton signals of benzene rings and NH group
contain singlet signals in the region 2.27–2.35 and
2.12–2.39 ppm, belonging to the protons of acyl
groups at the tertiary and secondary nitrogen atoms. In
the 13С NMR spectra of compounds 4 and 5 the spiro
atom gives rise to the signal at 97.58 and 93.16 ppm.
In order to prepare indeno[1,2-b]quinoxaline spiro-
jointed with the pyrazole ring we investigated the
reaction of chalcone 7 with hydrazine hydrate. The
reaction was performed at boiling the reagents mixture
in anhydrous ethanol for 1 h. IR, 1Н, 13С NMR spectra
of the reaction product showed that the reaction was
completed at the formation of methyl N-{4-(2',4'-
dihydrospiro[indeno[2,1-b]quinoxaline-11,3'-pyrazol]-
5'-yl)phenyl}carbamate 8 in 97% yield (Scheme 4).
The ring closure occurs evidently as a result of a
nucleophilic attack of oxygen or sulfur atom on the
electron-deficient carbon atom of the С=N bond and is
accompanied with the acylation of amino and imino
groups in the formed heterocycle.
1
In the Н NMR spectrum of spiro compound 8 the
The aldol crotonic condensation of 11Н-indeno-
[1,2-b]quinoxalin-2-one 1 with methyl N-(4-acetyl-
diastereotopic protons at the atom С4 appear as two
doublets at 3.75 and 3.89 ppm, same as in the spectra
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 51 No. 5 2015

VELIKORODOV et al.
676
Scheme 4.
N
N
N
.
NH2NH2
H2O
N
EtOH, Δ
O
HN
N
NHCO2Me
NHCO2CH3
7
8
Scheme 5.
CHO
O
O
NH2
NH2
H
N
CN
OH
+
OH
CO2H
+
+
+
Me
X
O(CO)NHPh
EtOH_[bmim]Br,
Δ, 7 h
9
H
O
N
Ph
Me
O
N
X
CN
N
N
10, 11
X = CN (10), CO2Et (11).
of other pyrazoles of analogous structure. In the 13С
NMR spectrum of compound 8 along with the signal of
the carbon atom of the С=N group (δ 153.75) the signal
of the spiro carbon atom is present at δ 68.79 ppm.
Analogous reactions were carried out either at
prolonged (12 h) heating in ethanol, or under
microwave irradiation [8].
The investigation of the condensation products by
1Н and 13С NMR spectroscopy showed that the
reactions led to the formation of 4-(1'-methyl-3',3'-
dicyanospiro[indeno[1,2-b]quinoxaline-11,2'-pyrro-
lidin]-4'-yl)phenyl N-phenylcarbamate 10 or of 4-(1'-
methyl-3'-cyano-3'-ethoxycarbonylspiro[indeno-[1,2-
b]quinoxaline-11,2'-pyrrolidin]-4'-yl)-phenyl N-phe-
nylcarbamate 11 in 78 and 75% yield respectively.
Aiming at obtaining a derivative of indeno[1,2-b]-
quinoxaline spiro-jointed with a pyrrole ring we studied
a 5-component condensation of ninhydrin, о-phenylene-
diamine, sarcosine, malononitrile (or ethyl cyanoace-
tate), and 4-formylphenyl N-phenylcarbamate 9 [7].
The condensation was carried out at vigorous
stirring of equimolar quantities of ninhydrin and о-
phenylenediamine in alcohol at room temperature for
10 min, then sarcosine, CH-acid, aldehyde 9, and ionic
liquid were added, and the mixture obtained was
boiled at TLC monitoring. The reaction completed in
7 h (Scheme 5).
The building up of compounds 10 and 11
proceeded through cascade reactions involving the
formation of 11Н-indeno[1,2-b]quinoxalin-2-one 1, the
generation of azomethine ylide 12 from sarcosine and
11Н-indeno[1,2-b]quinoxalin-2-one, and finally, the
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SYNTHESIS OF NEW SPIRO COMPOUNDS PROCEEDING FROM
677
Scheme 6.
PhHN(OC)O
_
CH2
N
CN
X
+
O
H
MeNHCH2CO2H
13, 14
10, 11
N
N
N
N
1
12
Х = CN (10, 13), CO2Et (11, 14).
[3+2]-cycloaddition reaction of azomethine ylide to
compounds 13 and 14 produced by the condensation of
the СН-acid with 4-formylphenyl N-phenylcarbamate
9 (Scheme 6).
249°С. IR spectrum, ν, cm–1: 3420, 3330–3310 (NH,
NH2), 1710 (C=O), 1630 (C=N), 1610, 1575, 1560,
1500 (C=Carom). 1120 (C=S). Found, %: C 62.90; H
3.62; N 23.01. C16H11N5S. Calculated, %: C 62.95; H
3.61; N 22.95.
EXPERIMENTAL
N-(3'-Acetyl-3'Н-spiro[indeno[1,2-b]quinoxalin-
11,2'-[1,3,4]oxadiazol]-5'-yl)acetamide (4). A mixture
of 0.58 g (2 mmol) of semicarbazone 2 in 5 mL of
freshly distilled acetic anhydride was boiled for 4 h,
cooled, poured in 50 mL of ice water, the formed
acetic acid was neutralized with solid sodium
carbonate. The separated precipitate was filtered off,
washed with water on the filter, dried in air, and
recrystallized from ethanol. Yield 0.67 g (89%), light
yellow crystals, mp 209–211°С. IR spectrum, ν, cm–1:
3320 (N–H), 1720 (C=O), 1630 (C=N), 1610, 1575,
1560 (C=C, C=Carom). 1Н NMR spectrum, δ, ppm: 2.27
s (3Н, NCOMe), 2.39 s (3H, NНCOMe), 7.25 t
(1Harom, J 7.3 Hz), 7.42 t (1Нarom, J 7.3 Hz), 7.60 d
(1Нarom, J 7.3 Hz), 7.65–7.78 m (4Нarom), 7.95 d
(1Нarom, J 7.3 Hz),12.24 br.s (1Н, NHСОMe). 13С
NMR spectrum, δ, ppm: 22.56 (NCOMe), 25.27
(HCOOCH3), 97.58 (spiro atom), 122.31, 124.12,
130.59, 132.98, 133.02, 142.04, 146.53 (Carom), 162.04
(C5), 167.13 (NCOMe), 168.20 (NHCOMe). Found,
%: С 64.29; Н 4.04; N 18.65. C20H15N5O3. Calculated,
%: С 64.34; Н 4.02; N 18.77.
1Н NMR spectra were registered on a spectrometer
Bruker DRX-500 (500.13 MHz). 13С NMR spectra were
taken on a spectrometer Bruker WM-400 (100 MHz) at
complete decoupling from protons, solvent DMSO-d6.
IR spectra were recorded on an IR Fourier
spectrophotometer Infralyum FT-02 in the range 4000–
400 cm–1 from pellets with KBr. The purity of
compounds obtained was checked by TLC on Silufol
UV-254 plates, development in iodine vapor. 11Н-
Indeno[1,2-b]quinoxalin-2-one 1 was prepared by
condensation of ninhydrin and о-phenylenediamine in
anhydrous ethanol in the presence of glacial acetic acid
by the known procedure [9], mp 225–227°С (mp 227–
229°С [10]).
11Н-Indeno[1,2-b]quinoxalin-2-one semicarbazo-
ne (2). A mixture of 1.16 g (5 mmol) of 11Н-indeno-
[1,2-b]-quinoxalin-2-one 1 and 0.56 g (5 mmol) of
semicarbazide hydrochloride in 100 mL of methanol
was stirred for 2 h at 45 С, cooled, the precipitated
crystalline reaction product was filtered off, washed
with cold ethanol, and recrystallized from dioxane.
Yield 1.4 g (97%), light yellow crystals, mp 237–238°С.
IR spectrum, ν, cm–1: 3420, 3340–3310 (NH, NH2),
1710 (C=O), 1630 (C=N), 1610, 1575, 1560, 1500
(C=Carom). Found, %: C 66.33; H 3.80; N 24.06.
C16H11N5O. Calculated, %: C 66.44; H 3.81; N 24.22.
N-(3'-Acetyl-3'Н-spiro[indeno[1,2-b]quinoxaline-
11,2'-[1,3,4]thiadiazol]-5'-yl)acetamide (5) was
obtained by the above procedure from 0.61 g (2 mmol)
of thiosemicarbazone 3 and 5 mL of freshly distilled
acetic anhydride. Yield 0.69 g (88%), light yellow
crystals, mp 296–297°С. IR spectrum, ν, cm–1: 3320
(N–H), 1720 (С=O), 1610, 1575, 1565 (С=С,
11Н-Indeno[1,2-b]quinoxalin-2-one thiosemicar-
bazone (3) was obtained by the above procedure from
1.16 g (5 mmol) of 11Н-indeno[1,2-b]quinoxalin-2-
one 1 and 0.46 g (5 mmol) of thiosemicarbazide 3.
Yield 1.55 g (95%), light yellow crystals, mp 247–
1
С=Сarom). Н NMR spectrum, δ, ppm: 2.12 s (3Н,
NHCOMe), 2.35 s (3H, NCOMe), 7.20 t (1Harom, J
7.2 Hz), 7.41 d (1Нarom, J 7.2 Hz), 7.51–7.54 m
(2Нarom), 7.67–7.70 m (2Нarom), 7.85 d (1Нarom, J 8.7 Hz),
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 51 No. 5 2015

VELIKORODOV et al.
678
8.11 d (1Нarom, J 7.2 Hz), 9.64 br.s (1Н, NHСОMe).
13С NMR spectrum, δ, ppm: 22.54 (NНCOMe), 22.87
(NCOCH3), 93.16 (spiro atom), 124.31, 125.50,
127.63, 128.92, 129.62, 130.48, 131.14, 133.87,
136.04, 137.02, 142.50 (Carom), 159.14 (С5), 165.86
(NCOMe), 167.45 (NHCOMe). Found, %: С 61.65; Н
3.88; N 17.89. C20H15N5O2S. Calculated, %: С 61.70;
Н 3.86; N 18.00.
132.56, 136.32, 138.27, 141.08, 145.26, 145.78 (Carom),
147.43 (NHCO2Me), 153.75 (C=N). Found, %: С
71.08; Н 4.50; N 16.41. C25H19N5O2. Calculated, %: С
71.26; Н 4.51; N 16.63.
4-(1'-Methyl-3',3'-dicyanospiro[indeno[1,2-b]-
quinoxaline-11,2'-pyrrolidin]-4'-yl)phenyl N-
phenylcarbamate (10). To a solution of 0.108 g of
(1 mmol) of о-phenylenediamine in 20 mL of
anhydrous ethanol was added 0.178 g (1 mmol) of
ninhydrin, and the mixture was vigorously stirred for
10 min, then 0.107 g (1.2 mmol) of sarcosine, 0.066 g
(1 mmol) of malononitrile, 0.24 g (1 mmol) of 4-
formylphenyl N-phenylcarbamate, and 1 g of ionic
liquid [bmim]Br was added. The mixture was boiled
for 7 h, cooled to room temperature, and poured in
50 mL of ice water. The separated precipitate was
filtered off, washed on the filter with water (2 × 50 mL),
dried in air, and recrystallized from chloroform. Yield
0.43 g (78%), yellow crystals, mp 117–118°С. IR
spectrum, ν, cm–1: 3320 (N–H), 2265 (C≡N), 1710
Methyl (E)-N-{4-[2-(11Н-indeno[2,1-b]quino-
xalin-11-ylidene)acetyl]phenyl}carbamate (7).
A
mixture of 2.32 g (0.01 mol) of 11Н-indeno[1,2-b]-
quinoxalin-2-one 1 and 1.93 g (0.01 mol) of methyl N-
(4-acetylphenyl)carbamate 6, and 0.5 mL of diethyl-
amine in 30 mL of anhydrous ethanol was boiled for
1 h and stored at 5°С for 48 h. The formed crystalline
reaction product was filtered off, mixed with 8 mL of
glacial acetic acid and 0.25 mL of conc. HCl, the
mixture was heated at 95°С for 0.5 h, 10 mL of ethanol
was added, the reaction mixture was cooled on an ice
bath, the separated crystalline reaction product was
filtered off, dried in air, and recrystallized from
dioxane. Yield 3.66 g (90%), yellow crystals, mp 155-
157°С. IR spectrum, ν, cm–1: 3320 (N–H), 1710, 1675
1
(С=O), 1610, 1575, 1565, (С=С, С=Сarom). Н NMR
spectrum, δ, ppm: 2.48 s (3Н, NMe), 3.11–3.17 m (1Н,
СН2), 4.00–4.07 m (2Н, СН2, СН), 6.94 t (1Нarom, J
7.8 Hz), 7.20–7.24 m (4Нarom), 7.34–7.40 m (3Нarom),
7.49–7.53 m (2Нarom), 7.58 d (1Нarom, J 8.0 Hz), 7.65–
1
(С=O), 1610, 1575, 1565 (С=С, С=Сarom). Н NMR
spectrum, δ, ppm: 3.71 s (3Н, NHCO2Me), 7.30 d
(2Нarom, J 8.5 Hz), 7.45–7.55 m (3Нarom), 7.70 s (1Н,
olefin proton), 7.72–7.77 m (2Нarom), 7.85 d (1Нarom, J
7.5 Hz), 7.96–8.01 m (3Нarom), 8.10 d (1Нarom, J
7.5 Hz) 9.58 br.s (1Н, NHСО2Me). Found, %: С
73.68; Н 4.21; N 10.24. C25H17N3O3. Calculated, %: С
73.71; Н 4.18; N 10.32.
7.73 m (3Нarom), 7.84–7.91 m (2Нarom), 8.20 d (1Нarom
,
J 7.3 Hz), 9.94 s (1Н, NH). 13С NMR spectrum, δ,
ppm: 41.28 (С3), 44.15 (NMe), 46.14 [С(C=N)2],
61.32 (C4), 75.80 (spiro atom), 110.16 (C≡N), 114.56
(C≡N), 122.91, 123.12, 124.54, 126.21, 126.50,
127.69, 128.93, 130.15, 131.70, 132.14, 133.40,
134.10, 135.01, 138.14, 139.02, 141.94, 147.50,
148.24, 151.02 (Carom), 154.87 (PhNHCO2), 162.14
(С3). Found, %: С 74.51; Н 4.27; N 15.29.
C34H24N6O2. Calculated, %: С 74.45; Н 4.38; N 15.33.
Methyl N-{4-(2',4'-dihydrospiro[indeno[2,1-b]-
quinoxaline-11,3'-pyrazol]-5'-yl)phenyl}carbamate
(8). A mixture of 2.04 g (5 mmol) of chalcone 7 and
0.18 g (5.5 mmol) of 99% hydrazine hydrate in 10 mL
of ethanol was boiled for 1 h, cooled to room
temperature, the formed precipitate was filtered off,
washed on the filter with 10 mL of ethanol, 5 mL of
ethyl ether, and recrystallized from ethanol. Yield
2.05 g (97%), light yellow crystals, mp 233–234°С. IR
spectrum, ν, cm–1: 3310 (N–H), 1710 (С=O), 1640
4-(1'-Methyl-3'-cyano-3'-ethoxycarbonylspiro-
[indeno[1,2-b]quinoxaline-11,2'-pyrrolidin]-4'-yl)
phenyl N-phenylcarbamate (11) was obtained
similarly from 0.108
g
(1 mmol) of о-
phenylenediamine, 0.178 g (1 mmol) of ninhydrin,
0.107 g (1.2 mmol) of sarcosine, 0.11 mL (1.04 mmol)
of freshly distilled ethyl cyanoacetate, 0.24 g (1 mmol)
of 4-formylphenyl N-phenylcarbamate, and 1 g of
ionic liquid [bmim]Br. Yield 0.45 g (75%), yellow
crystals, mp 99–100°С (from chloroform). IR
spectrum, ν, cm–1: 3320 (N–H), 2262 (C≡N), 1710, 1695
1
(C=N), 1615, 1575, 1565 (С=С, С=Сarom). Н NMR
spectrum, δ, ppm: 3.71 s (3Н, NHCO2Me), 3.75 d
(1НА, СН2, J 11 Hz), 3.89 d (1НВ, СН2, J 11 Hz), 7.17
t (1Нarom, J 7.7 Hz), 7.32–7.39 m (3Нarom), 7.59–7.69 m
(3Нarom), 7.73–7.79 m (4Нarom), 7.95 d (1Нarom, J 7.3 Hz),
8.78 s (1Н, NH pyrazole), 9.63 br.s (1Н, NHСО2Me).
13С NMR spectrum, δ, ppm: 43.55 (С4), 51.65
(NHCO2Me), 68.79 (spiro atom), 117.58, 123.50,
125.90, 128.14, 128.52, 130.54, 130.68, 130.70,
1
(С=O), 1610, 1585, 1560 (С=С, С=Сarom). Н NMR
spectrum, δ, ppm: 1.23 t (3Н, СН2СН3, J 6.5 Hz), 2.35
s (3Н, NMe), 3.15–3.20 m (1Н, СН2), 4.02–4.06 m
(1Н, СН), 4.09 q (2Н, СН2СН3, J 6.5 Hz), 4.19–4.23
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 51 No. 5 2015

SYNTHESIS OF NEW SPIRO COMPOUNDS PROCEEDING FROM
679
2. Selvam, P., De Clereq, E., and Pannecouque, C., Int.
J. Drug Des. Dis., 2013, vol. 4, p. 1017.
3. Shaabanzadeh, M. and Khabari, F., ARKIVOC, 2009,
m (1Н, СН2), 6.95 t (1Нarom, J 7.8 Hz), 7.12 d (2Нarom
,
J 8.0 Hz), 7.21–7.45 m (8Нarom), 7.66–7.78 m (5Нarom),
8.12 d (1Нarom, J 7.3 Hz), 9.94 s (1Н, NH). 13С NMR
spectrum, δ, ppm: 14.35 (СН2СН3), 41.58 (NMe),
44.59 (С3), 59.37 (СН2СН3), 61.13 (С2), 65.45 (С4),
75.45 (spiro atom), 120.42 (Carom), 121.50 (C≡N),
122.90, 126.14, 125.30, 125.50, 125.82, 129.90,
130.01, 130.24, 130.32, 131.15, 131.98, 132.60,
134.52, 135.20, 138.01, 139.20, 142.24, 147.08,
149.89 (Carom), 153.96 (PhNHCO2), 162.83 (СO2Et).
Found, %: С 72.38; Н 4.90; N 11.65. C36H29N5O4.
Calculated, %: С 72.61; Н 4.87; N 11.77.
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