Synthesis of heterocyclic nitrogen derivatives from aryl-1,4-benzoquinones

Article abstract of DOI:10.1002/jhet.5570380126

Treatment of 2-aryl-3,6-bis(arylamino)-1,4-benzoquinones 2a-h with different acid chlorides, namely acetyl, phenylacetyl and chloroacetyl chloride yields 3a,7a-dihydropyrrolo[2,3-f]indole-2,6-dione 3, 5-(N-phenylacetylarylamino)-3-phenylindole-2,6-dione 4 and 3-chloro-5-(N-chloroacetylarylamino) indole-2,6-dione 5 respectively. Stirring 2-aryl-1,4-benzoquinones (1) with ethylenediamine and/or o-phenylenediamine in methylene chloride gives pyrazino[2,3-g]quinoxalines derivative 6 and/or tetrapentacene derivative 7 respectively. The products 5-aryl- and 6-aryl-1H-indazole-4,7-diones 8 and 9 were obtained in the 1,3-dipolar cycloaddition of diazomethane to (1).

Full text of DOI:10.1002/jhet.5570380126

Jan-Feb 2001
Synthesis of Heterocyclic Nitrogen
179
Derivatives from Aryl-1,4-benzoquinones
*
Mamdouh A. Hassan, Ragab F. Fandy and Tark M. El-Amine
Chemistry Department, Faculty of Science, South Valley University, Qena, Egypt
Received February 16, 1999
Treatment of 2-aryl-3,6-bis(arylamino)-1,4-benzoquinones 2a-h with different acid chlorides, namely
acetyl, phenylacetyl and chloroacetyl chloride yields 3a,7a-dihydropyrrolo[2,3-f]indole-2,6-dione 3,
5-(N-phenylacetylarylamino)-3-phenylindole-2,6-dione 4 and 3-chloro-5-(N-chloroacetylarylamino)indole-
2,6-dione 5 respectively. Stirring 2-aryl-1,4-benzoquinones (1) with ethylenediamine and/or o-phenyl-
enediamine in methylene chloride gives pyrazino[2,3-g]quinoxalines derivative 6 and/or tetrapentacene
derivative 7 respectively. The products 5-aryl- and 6-aryl-1H-indazole-4,7-diones 8 and 9 were obtained in
the 1,3-dipolar cycloaddition of diazomethane to (1).
J. Heterocyclic Chem., 38, 179 (2001).
Owing to the importance of quinones which posses a
wide spread application in various fields including use as
fungicides [1-3], antibacterial [4-6], antimalarial [7] and as
antitumoral [8], we decided to synthesize some new
heterocyclic quinones starting with aryl-1,4-benzoquinones
(1) [9] hoping that such compounds would have certain
required biological effects or other industrial applications.
In extension of the work by one of us on the synthesis of
heterocyclic quinones, naphtho[2,3-d]imidazole-4,9-diones
[10], the action of aromatic amines on 1a-c followed by
acetylation in order to synthesize pyrroloindoles and
indoles now has been investigated. Thus, when 1a-c were
treated with aromatic amines namely aniline, p-toluidine
and p-anisidine in absolute ethanol, 2-aryl-3,6-bis(aryl-
amino)-1,4-benzoquinones 2a-h were obtained.
peak at δ 6.1-6.3 corresponding to the (H ) in the quinone
ring. Some of the physical and spectroscopic data of
compounds 2 are summarized in Tables 1 and 2.
5
The reaction of 2 with acetyl chloride in dry benzene in
the presence of triethylamine gives 1,4,5-triaryl-
3a,7a-dihydropyrrolo[2,3-f]indole-2,6-dione 3a-c. The
structures of these compounds were established by their
spectra. IR spectra showed the disappearance of any
absorption band characteristic for NH, and showed a
-1
strong absorption band at 1700-1685 cm characteristic of
the amide carbonyl group (cf. Table 2).
Formation of compounds 3 are assumed to proceed via
(i) acetylation of both NH groups in 2 and (ii) a cyclo-
condensation reaction between the activated methyl
groups and the carbonyl groups of quinone (Scheme 1).
The reaction of 2 with other acid chlorides, namely
phenylacetyl chloride and chloroacetyl chlorides, were
carried out under a similar condition to afford
The structures of these products were supported by their
spectral and elemental data. IR spectra for 2a-h revealed the
-1
presence of corresponding bands at 3350-3250 cm due to ν
NH and the presence of strong absorption bands at 1650-1710
-1
1
cm which are characteristic for ν CO of quinones. H-nmr
data showed two broad bands peaks at δ 8.2-8.4 which are
characteristic of the presence of two NH groups and a singlet

180
Vol. 38
M. A. Hassan, R. F. Fandy and T. M. El-Amine
Table 1
Physical and Analytical Data of Compounds 2, 3, 4, 5, 6 and 7
Appearance
CommppoundYield Molecular
Elemental
No.
Ar
Ar'
(%)
(°C)
Formula
Analysis
Found/(Calcd.)
H
C
N
2a
2b
2c
2d
2e
2f
C H
C H
55
58
60
60
62
68
63
60
44
38
39
25
27
44
42
40
55
58
40
32
42
red crystals
red crystals
201-202
202-204
208-209
233-234
207-208
208-209
230-232
254–256
118-120
98-100
C
C
C
C
C
C
H
N O
78.62
(78.67)
79.09
(79.15)
73.20
(73.21)
78.89
(78.90)
79.45
(79.38)
73.58
(73.61)
71.95
(71.99)
72.75
(72.88)
81.26
(81.14)
81.44
(81.28)
81.62
(81.55)
82.32
(82.17)
82.38
(82.33)
67.06
(67.20)
67.79
(67.70)
68.48
(68.62)
74.30
4.93
(4.96)
5.60
(5.63)
5.19
(5.21)
5.30
(5.31)
5.69
(5.93)
5.52
(5.50)
4.30
(4.29)
4.90
(4.95)
4.29
(4.39)
4.60
(4.71)
5.23
(5.31)
4.77
(4.84)
5.19
(5.26)
3.56
(3.63)
3.87
(3.93)
4.39
7.62
(7.69)
7.12
(7.10)
8.54
(8.57)
7.32
(7.36)
6.84
(6.86)
6.38
(6.36)
7.01
(7.00)
6.58
(6.54)
6.70
(6.76)
6.42
(6.54)
6.09
(6.14)
4.80
(4.79)
4.70
(4.57)
5.52
(5.60)
5.42
(5.45)
5.08
6
5
5
5
6
5
24 18
2
2
2
4
2
2
4
(366.4)
H N O
26 22 2
(394.5)
H N O
26 22 2
(426.5)
H N O
25 20 2
(380.5)
H N O
27 24 2
(408.5)
H N O
27 24 2
(440.5)
H N O Cl
C H
p-C H CH
6
6
4
3
C H
p-C H OCH
reddish brown
crystals
red crystals
6
4
4
3
p-C H CH
C H
6
4
3
3
3
6
5
p-C H CH
p-C H CH
red crystals
violet crystals
violet crystals
brown crystals
6
4
6
4
3
p-C H CH
p-C H OCH
6
4
6
4
3
2g
2h
3a
3b
3c
4a
4b
5a
5b
5c
6a
6b
7a
7b
7c
p-C H Cl
C H
C
6
4
6
5
24 17 2 2
(400.41)
H N O Cl
26 21 2 2
p-C H Cl
p-C H CH
C
6
4
6
4
3
(428.47)
C H N O
28 18
C H
C H
bluish violet
micro crystals
blue
micro crystals
blue
micro crystals
reddish violet
fine crystals
reddish violet
fine crystals
violet
fine crystals
violet
micro crystals
violet
micro crystals
yellow
6
5
6
5
5
2
2
2
2
3
3
(414.46)
H N O
29 20 2
p-C H CH
C H
C
C
C
C
6
4
3
6
( 428.49 )
N O
p-C H CH
p-C H CH
100-102
108-110
95-96
H
31 24 2
6
4
3
6
4
3
( 456.55)
H N O
40 28 2
(584.67)
H N O
42 32 2
C H
C H
6
5
5
5
6
5
C H
p-C H CH
6
6
4
3
(612.70)
N O Cl
C H
C H
183-185
100-102
142-144
99-101
C
H
6
6
5
5
28 18
2
3
(500.45)
H N O C
29 18 2 3
p-C H CH
C H
C
6
4
3
3
3
6
(514.48)
C H N O Cl
31 24
p-C H CH
p-C H CH
6
4
6
4
3
2
3
2
(542.54)
(4.47)
5.06
(5.16)
20.34
p-C H CH
(H)
(H)
(H)
(H)
(H)
C H N
6
4
17 14 4
crystals
yellow
crystals
yellow
needles
yellow
needles
yellow
(274.35)
H N Cl
16 11 4
(294.31)
(74.42)
65.17
(65.29)
79.94
(79.97)
80.14
(80.18)
73.23
(5.15) (20.43)
3.69 18.97
(3.77) (19.44)
4.53 15.50
(4.48) (15.55)
4.69 14.88
(4.85) (14.97)
4.03 13.98
(3.83) (14.19)
p-C H Cl
114-115
173-175
115-117
102-103
C
6
4
C H
C H N
6
5
24 16 4
(360.44)
p-C H CH
C H N
6
4
3
25 18 4
(374.74)
H N Cl
24 15 4
(394.76)
p-C H Cl
C
6
4
needles
(73.02)

Jan-Feb 2001
Synthesis of Heterocyclic Nitrogen Derivatives from Aryl-1,4-benzoquinones
181
Table 2
Spectroscopic Data of Compounds 2, 3, 4, 5, 6 and 7
1
CompoundMS
No.
IR
H-NMR ( δ ppm)
-1
Ar
Ar'
m/e
(cm
)
(CDCl )
3
base peak ( %)
(NH,CO)
2a
2b
2c
C H
C H
6 5
3330
1660
3250
1700
3250
1670
3250
1660
3250
1710
3300
1680
8.2, 8.4 (2s, 2H, 2NH), 6.5-7.5 (m, 15H, Ar), and 6.2
(s, 1H, H5 qu.).
8.4, 8.6 (2s, 2H, 2NH), 6.7-7.6 (m, 13H, Ar), 6.1
6
5
5
5
C H
p-C H CH
3
6
6
4
(s, 1H, H5 qu.) and 2.1, 2.3 (2s, 6H, 2CH ).
3
C H
p-C H OCH
8.2, 8.4 (2s, 2H, 2NH), 6.4-7.4 (m, 13H, Ar), 6.0
6
4
4
3
(s, 1H, H5 qu.) and 3.6, 3.8 (2s, 6H, 2OCH ).
3
+.
2d
2e
2f
p-C H CH
C H
6 5
380 (M , 100)
8.2, 8.4 (2s, 2H, 2NH), 6.6-7.5 (m, 14H, Ar), 6.1
6
4
3
3
3
(s, 1H, H5 qu.) and 2.1 (s, 3H, CH ).
3
p-C H CH
p-C H CH
3
8.2, 8.4 (2s, 2H, 2NH), 6.4-7.4 (m, 12H, Ar), 6.1
6
4
6
4
(s, 1H, H5 qu.) and 2.1, 2.3, 2.4 (3s, 9H, 3CH ).
3
p-C H CH
p-C H OCH
8.1, 8.3 (2s, 2H, 2NH), 6.3-7.4 (m, 12H, Ar),
6
4
6 4
3
6.0 (s, 1H, H5 qu.), 3.7, 3.9 (2s, 6H, 2OCH ) and 2.2
3
(s, 3H, CH ).
3
2g
2h
3a
3b
3c
4a
4b
5a
5b
5c
6a
p-C H Cl
C H
6 5
3250
1650
3300
1660
1685
8.1, 8.3 (2s, 2H, 2NH), 6.2-7.2 (m, 14H, Ar) and 6.1
(s, 1H, H5 qu.).
8.2, 8.4 (2s, 2H, 2NH), 6.4-7.3 (m, 12H, Ar), 6.1
6
4
+.
p-C H Cl
p-C H CH
3
428 (M , 31.4)
6
4
6
4
36 (100)
(s, 1H, H5 qu.) and 2.2, 2.4 (2s, 6H, 2CH ).
3
+.
C H
C H
414 (M , 27.7)
6.5-7.9 (m, 15H, Ar), 6.1 (s, 1H, H8) and 4.1
(s, 2H, H3 + H7).
6.6-7.5 (m, 14H, Ar), 6.1 (s, 1H, H8), 4.2, 4.4
6
5
6
5
5
281(100)
+.
p-C H CH
C H
428 (M , 6)
1790
1690
6
4
3
6
281 (100)
(2s, 2H, H3, H7) and 2.0 (s, 3H, CH ).
3
+.
p-C H CH
p-C H CH
456 (M , 9.2)
6.4-7.8 (m, 12H, Ar), 6.2 (s, 1H, H8), 4.2
6
4
3
6
4
3
274 (100)
(s, 2H, H3 + H7) and 2.0, 2.1, 2.3 (3s, 9H, 3CH ).
3
C H
C H
1690
1710
1690
1710
1680
1695
1680
1700
1685
1695
3300
3350
6.7-7.8 (m, 26H, Ar + H4) and 3.1-3.2 (d, 2H, CH ).
2
6
5
5
5
6
5
C H
p-C H CH
6.8-7.8 (m, 24H, Ar + H4), 3.0-3.1 (d, 2H, CH ) and
2
6
6
4
3
1.24, 1.25 (2s, 6H, 2CH ).
3
+.
35
C H
C H
500 (M ,5.56,Cl
504 (M ,1.41,Cl
)
)
6.6-7.6 (m, 15H, Ar), 6.3 (s, 1H, H4) and 3.9-4.0
6
6
5
5
+.
37
(d, 2H, CH ).
2
p-C H CH
C H
6.7-7.5 (m, 14H, Ar), 6.3 (s, 1H, H4), 3.9-4.0
6
4
3
3
3
6
(d, 2H, CH ) and 2.4 (s, 3H, CH ).
2
3
p-C H CH
p-C H CH
6.5-7.4 (m, 12H, Ar), 6.2 (s, 1H, H4), 3.9-4.0
(d, 2H, CH ) and 2.2, 2.3, 2.4 (3s, 9H, 3CH ).
6
4
6
4
3
2
3
p-C H CH
(H)
6.9-7.4 (m, 4H, Ar), 6.55 (m, 3H, H3 + H8+ H10),
6.4 (dd, 2H, H2 + H7), 2.5 (s, 2H, 2NH)
6
4
and 2.3 (s, 3H, CH ).
3
6b
7a
7b
7c
p-C H Cl
(H)
(H)
(H)
(H)
3300
3360
3300
3380
3320
3400
3330
3400
7.2-7.4 (m, 4H, Ar), 6.7 (m, 3H, H3 + H8 + H10), 6.6
(dd, 2H, H2, H7) and 2.7 (s, 2H, 2NH).
8.0, 8.1 (2s, 2H, 2NH), 7.5-7.6 (m, 5H, Ar), 7.1-7.3
(m, 8H, H1-H4 + H8-H11) and 6.7 (s, 1H, H13).
8.0, 8.1 (2s, 2H, 2NH), 7.25-7.35 (m, 4H, Ar), 6.7-6.9
6
4
C H
6
5
p-C H CH
6
4
3
(m, 9H, H1-H4 + H8-H11+H13) and 2.4 (s, 3H, CH ).
3
p-C H Cl
7.9, 8.0 (2s, 2H, 2NH), 7.1-7.3 (m, 4H, Ar) and 6.6-6.8
(m, 9H, H1-H4 + H8-H11 + H13).
6
4
5-(N-phenylacetylarylamino)-1,7-diaryl-3-phenylindole-
2,6-dione 4a,b and 5-(N-chloroacetylarylamino)-
1,7-diaryl-3-chloroindole-2,6-dione 5a-c respectively.
The compounds 4 and 5 were formed by acylation of
NH groups followed by cyclocondensation occurring at
the more electrophilic carbonyl group at C-4 whose polar
resonance form is stabilized by the aromatic substituent.
Attempts to convert 4 and 5 into the pyrroloindole deriva-
tives showed that these products were extremely stable.
The analytical and spectroscopic data were in full agree-
ment with the assigned structures (Tables 1 and 2).
We completed our investigation by examining the
behavior of 2-aryl-p-benzoquinones (1) toward 1,2-
diamines. The dehydrogenated products 5-aryl-1,6-
dihydropyrazino[2,3-g]quinoxalines 6a,b were synthe-
sized by stirring of 1b,c with ethylenediamine in
methylene chloride. On the other hand, the reaction of 1
with o-phenylenediamine in glacial acetic acid or by
stirring at room temperature in methylene chloride
afforded 6-aryl-5,12-dihydro-5,7,12,14-tetraza-
pentacenes 7a-c. The ir spectra of compounds 6 and 7
revealed the absence of ν CO of the quinone and the

182
Vol. 38
M. A. Hassan, R. F. Fandy and T. M. El-Amine
8-12 hours, then filtered hot to separate the precipitated triethyl-
amine hydrochloride. Reflux was then continued for a further
4 hours, where a stable reddish violet solution was obtained. The
solvent was removed on vacuo and the solid residues were
purified by using preparative thin layer chromatograph
(benzene:light petroleum, 7:3). The fastest migrating dark zone
was extracted with chloroform and the crude product obtained on
evaporation of the extracts was rechromatographed with the same
eluent to give 3, 4 and 5. Yields, melting points, analytical and
spectroscopic data are listed in Tables 1 and 2.
5-Aryl-1,6-dihydropyrazino[2,3-g]quinoxalines (6a,b).
-1
presence of the NH band at 3400-3200 cm . Analytical
and spectroscopic data of compounds 6 and 7 are listed
in Tables 1 and 2.
To (0.02 mole) of 1 in 50 ml methylene chloride, (0.02 mole) of
ethylenediamine was added and the reaction mixture was stirred at
room temperature for 48 hours. The precipitate formed was collected
and recrystallized from methylene chloride to give 6. For yields,
melting points, analytical and spectroscopic data see Tables 1 and 2.
The cycloaddition of 1,3-dipoles, such as diazoalkanes,
azides, nitrilimines and nitrile oxides, to 1,4-quinone
dipolarophiles provides an excellent one step synthesis of
heterocyclic nitrogen quinones [11]. 1,3-Dipolar cyclo-
addition of monosubstituted p-benzoquinones with
diazomethane, gives rise to two possible regioisomeric
products [12]. Treatment of 1a and 1b with 3 equivalent
ethereal diazomethane at 0-5 ºC afforded a mixture of
undistinguished isomers 5-aryl- and 6-aryl-1H-indazole-
4,7-diones (8, 35% overall yield 2:1 and 9, 38% overall
6-Aryl-5,12-dihydro-5,7,12,14-tetrazapentacenes (7a-c).
o-Phenylenediamine (2.16 g, 0.02 mole) was added to a
solution of 1 (0.01 mole) in methylene chloride (30 ml) at room
temperature and the reaction mixture was stirred for 48 hours.
The precipitate formed was collected and recrystallized from
methylene chloride to give 7a-c. Yields, melting points,
analytical and spectroscopic data are listed in Tables 1 and 2.
General Procedure for the Preparation of 5-Aryl- and 6-Aryl-1H-
indazole-4,7-diones (8 and 9).
1
yield 3:1) as evidenced by the 300 MHz H-nmr spectra in
which the integration of the protons at position 3 and of
methyl in 9 were used to find the percentage ratio. All
attempts to separate the two isomeric products using
preparative tlc, column chromatography, and fractional
crystallization were unsuccessful. All the analytical and
spectral data (ir, nmr and ms) were in full agreement with
the proposed isomeric structures.
A solution of diazomethane in ether (10 mL, 0.03 mole) was
added dropwise to a cold stirred solution of 2-aryl-1,4-benzo-
quinone (1) (0.01 mole) in ether/acetone (10:1). The reaction
mixture was transformed into a brown solution after the
diazomethane solution had been completely added; the solution
was stirred for 2 hours at 0-5 ºC. The mixture was
chromatographed on tlc plates using benzene as an eluent. The
upper yellow zone was extracted with acetone, which evaporated
under vacuum and the solid formed was crystallized from
benzene to yield the desired yellow isomeric products 8 and 9.
EXPERIMENTAL
Melting points were determined on an electric melting points
apparatus (Gallenkamp) and were uncorrected. The ir spectra
(KBr) were recorded on a Shimadzu 408 spectrometer. The
5-Phenyl- and 6-Phenyl-1H-indazole-4,7-diones (8a,b).
This compound was obtained by reaction of 2-phenyl-p-benzo-
quinone (1a) (0.01 mole, 1.84 g) with diazomethane (10 mL, 0.03
mole, 1.26 g) as yellow crystals (0.8 g, 35% overall yield); mp
1
H-nmr spectra were recorded by 300 MHz Varian NMR
spectrometer and chemical shifts are reported in ppm with TMS
as an internal standard. Electron impact mass spectra were
obtained at 70 eV using a GCMS sp. 1000 Shimadzu at Cairo
University. Elemental analysis was carried out at the
Microanalysis Unit at Assiut University.
-1
1
170-180 ºC (dec); ir: 3350 (NH), 1670 (CO qu.) cm ; H-nmr
(deuteriochloroform): 7.82, 7.94 (2d, 2H, H-3 of 8a, 8b, J = 8
Hz), 7.00-7.55 (m, 12H, 10H Ar + H-5 + H-6) and 6.7, 6.8
(2d, 2H, 2NH, J = 8 Hz).
Anal. Calcd. for C H N O : C, 69.64; H, 3.57; N, 12.50.
Found: C, 69.55; H, 3.59; N, 12.49.
13
8 2 2
2-Aryl-3,6-bis(arylamino)-1,4-benzoquinone (2a-h).
To (0.01 mole) of 2 in 50 ml absolute ethanol was added
(0.02 mole) of pure primary aromatic amine, the reaction mixture
was then refluxed for 3-5 hours. The precipitate formed after cooling
was collected and recrystallized from benzene to give 2a-h. Yields,
melting points and analytical data are summarized in Table1.
5-(p-Tolyl)- and 6-(p-Tolyl)-1H-indazole-4,7-diones (9a,b).
This compound was obtained by reaction of 2-(p-tolyl)-p-
benzoquinone (1b) (0.01 mole, 1.98 g) with diazomethane
(10 mL, 0.03 mole, 1.26 g) as yellow fine crystals (0.9 g, 38 %
overall yield); mp 214-230 ºC (dec); ir: 3320 (NH), 1690
General Procedure for the Reaction of 2-Aryl-3,6-
bis-(arylamino)-1,4-benzoquinone (2) with Acids Chlorides.
-1
1
(CO qu.) cm ; H-nmr (deuteriochloroform): 8.25, 8.35 (2d, 2H,
H-3 of 9a, 9b, J = 8 Hz); 7.0-7.50 (m, 8H, Ar); 6.85, 6.95 (2s, 2H,
Compound 2 (0.01 mole) was dissolved in 50 ml dry benzene
then the proper acid chloride (0.03 mole) was added in the
presence of a catalytic amount of triethylamine (0.03 mole). The
reaction mixture was refluxed with continuous stirring for
H-5 and H-6); 6.6, 6.7 (2d, 2H, 2NH, J = 8 Hz) and 2.3, 2.45
+.
(2s, 6H, 2CH ); ms: 238 (M , 100 %).
3
Anal. Calcd. for C H N O : C, 70.58; H, 4.24; N, 11.76.
14 10
2 2
Found: C, 70.51; H, 4.18; N, 11.75.

Jan-Feb 2001
Synthesis of Heterocyclic Nitrogen Derivatives from Aryl-1,4-benzoquinones
183
REFERENCES AND NOTES
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