Cyclization of 2-arylamino-1,4-naphthoquinones to benzo[b]phenazine-6,11-dione 5-oxides

Article abstract of DOI:10.1007/s11172-014-0500-3

A method for the synthesis of a new group of tetracyclic diazaquinones, viz., benzo[b]-phenazine-6,11-dione 5-oxides, was developed and the pathways of their further modifications were outlined.

Full text of DOI:10.1007/s11172-014-0500-3

Russian Chemical Bulletin, International Edition, Vol. 63, No. 3, pp. 739—743, March, 2014
739
Cyclization of 2ꢀarylaminoꢀ1,4ꢀnaphthoquinones
to benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxides
L. M. Gornostaev,a Yu. G. Khalyavina, T. I. Lavrikova, G. A. Stashina, S. I. Firgang, and V. V. Chernyshevc,d
a
a
b
b†
aV. P. Astaf´ev Krasnoyarsk State Pedagogical University,
8
9 ul. A. Lebedevoi, 660049 Krasnoyarsk, Russian Federation.
Eꢀmail: gornostaev@kspu.ru
b
N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences,
4
7 Leninsky prosp., 119991 Moscow, Russian Federation.
Eꢀmail: galina_stashina@chemicalꢀblock.com
c
M. V. Lomonosov Moscow State University, Department of Chemistry,
Build. 3, 1 Leninskie Gory, 119991 Moscow, Russian Federation.
Eꢀmail: vladimir@struct.chem.msu.ru
d
A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences,
Korp. 4, 31 Leninsky prosp., 119071 Moscow, Russian Federation
A method for the synthesis of a new group of tetracyclic diazaquinones, viz., benzo[b]ꢀ
phenazineꢀ6,11ꢀdione 5ꢀoxides, was developed and the pathways of their further modifications
were outlined.
Key words: 2ꢀarylaminoꢀ1,4ꢀnaphthoquinones, cyclization, nitrosylsulfuric acid, benzo[b]ꢀ
phenazineꢀ6,11ꢀdiones, benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxides.
Polycyclic azaquinones posses various biological acꢀ
tivity and are promising for practical use in other direcꢀ
tions. For example, tricyclic diazaquinones (1) exhibit high
anticancer activity, tetracyclic benzo[b]phenazineꢀ6,11ꢀ
diones (2) and products of their modification are under
studies for potential use as dyes.2
yield of phenazines 4 in these cases is low; besides them,
2ꢀaminoꢀ3ꢀarylaminoꢀ1,4ꢀnaphthoquinones (5) are also
formed (Scheme 1).
We found that 2ꢀarylaminoꢀ1,4ꢀnaphthoquinones
(6a—d) treated with nitrosylsulfuric acid in acetic acid are
converted to benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxides
1
(
7a—d) (Scheme 2).
Note that 2ꢀphenylaminoꢀ1,4ꢀnaphthoquinone (6a)
treated with fuming nitric acid gives 2ꢀ(4ꢀnitrophenꢀ
4
ylamino)ꢀ1,4ꢀnaphthoquinone, whereas 2ꢀarylaminoꢀ
3
ꢀchloroꢀ1,4ꢀnaphthoquinones (6) are nitrated with
5
the nitrating mixture at the arylamino group and underꢀ
go nitrosation at the nitrogen atom with sodium nitrite
in acetic acid.6 Thus, the reaction of aminoquinoꢀ
nes 6a—d with nitrosylsulfuric acid takes another pathꢀ
way than that described in the literature. We believe
that the reaction of compounds 6a—d with nitrosylꢀ
As a rule, the reaction of 2ꢀarylaminoꢀ3ꢀchloroꢀ1,4ꢀ
naphthoquinones (3) with sodium azide2 is used for obꢀ
taining benzo[b]phenazineꢀ6,11ꢀdiones (4), however, the
,3
Scheme 1
X = H, OH; R = H, Me, Cl, OMe, NO2
†
Deceased.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 0739—0743, March, 2014.
066ꢀ5285/14/6303ꢀ0739 © 2014 Springer Science+Business Media, Inc.
1

740
Russ.Chem.Bull., Int.Ed., Vol. 63, No. 3, March, 2014
Gornostaev et al.
Scheme 2
O(19)
O(20)
C(2)
C(15)
N(1)
C(12) F(22)
C(3)
C(4)
C(14)
C(13)
C(11)
C(5)
C(16)
C(17)
C(10)
C(18)
C(9)
C(6)
C(7)
N(8)
O(21)
Fig. 1. Molecular structure and atoms numbering scheme in
compound 7d. Nonhydrogen atoms are shown as the spheres of
atomic displacements with 50% probability.
products 7 even upon prolonged stirring. Apparently,
amines 6 are completely protonated in concentrated sulꢀ
furic acid, and their protonated forms do not react with
nitrosonium cation.
R = H (a), Me (b), Cl (c), F (d)
The structure of phenazine Nꢀoxides 7 was confirmed
by Xꢀray powder analysis for 2ꢀfluorobenzo[b]phenazineꢀ
6,11ꢀdione 5ꢀoxide (7d). Figure 1 prepared by the PLATON
sulfuric acid follows the radical cation mechanism
(
Scheme 3).
9
It is known that cyclization of 2ꢀnitrosodiarylamines
program shows molecular structure of compound 7d.
7,8
to the corresponding phenazine Nꢀoxides takes place
Geometric parameters of molecule 7d (bond distances
and bond angles) have normal values comparable with
similar parameters found in the Cambridge Structural
upon treatment with nitrous acid. A radical cation mechaꢀ
7
nism is postulated for such cyclizations. Apparently, the
1
0
found by us heterocyclization 67 can follow such a pathꢀ
way involving orthoꢀnitrosodiarylamines 8, which fail to
be detected.
It is interesting that compounds 6 treated with nitrosylꢀ
sulfuric acid in concentrated sulfuric acid fail to convert to
Database. The crystal packing is characterized by the
absence of the —ꢀinteractions, that is balanced by the
presence of weak intermolecular hydrogen bonds C—H...O
(Table 1), which bound the planar molecules to chains
along the [120] direction (Fig. 2).
Scheme 3

Synthesis of benzo[b]phenazineꢀ6,11ꢀdioneꢀ12ꢀoxdes Russ.Chem.Bull., Int.Ed., Vol. 63, No. 3, March, 2014
741
a
to nucleophilic substitution. We found that phenazine
0
Nꢀoxide 7d readily reacts with cyclic amines (Scheme 5).
b
Scheme 5
c
Fig. 2. Molecular chains in the crystal structure 7d bonded by
weak intermolecular hydrogen bonds C—H...O (shown by the
thin lines). The Figure was prepared using the Mercury proꢀ
gram.11
In conclusion, we developed a convenient method for
the preparation of a new group of tetracyclic diazaquinoꢀ
nes, benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxides (7a—d) and
outlined directions of their further modifications to poꢀ
tentially biologically active compounds.
Compounds 7 are obtained from aminoquinones 6 in
high yields and can be further modified. For example,
phenazine Nꢀoxide 7a was reduced with hydrazine to
benzo[b]phenazineꢀ6,11ꢀdione (4a) in 89% yield (Scheme 4).
3
Note that in the known method for the preparation of
this product from 2ꢀanilinoꢀ3ꢀchloroꢀ1,4ꢀnaphthoquinoꢀ
ne and sodium azide, the yield was no more than 50%.
Experimental
1H NMR spectra were recorded on a Bruker DRXꢀ500 specꢀ
trometer (500 MHz) in DMSOꢀd and CDCl , using SiMe as
Scheme 4
6
3
4
an internal standard. The reaction progress and individuality of
obtained compounds were monitored by TLC on Silufol UVꢀ254
plates, eluent toluene—acetone (5 : 1). Melting points were meaꢀ
sured on a Boetius heating microstage. Molecular weights of the
synthesized compounds were confirmed by mass spectrometry
performed on a Finnigan MAT 8200 instrument. Electron abꢀ
sorption spectra were recorded on an Evolution 300 spectrophoꢀ
–
4
–1
tometer in DMF with a 1ꢀcm pathway and a 1•10 mol L
concentration. IR spectra were recorded on a Tensor 27 spectroꢀ
meter in KBr pellets.
The crystal structure of compound 7d was determined by
1
2—14
Xꢀray powder diffraction analysis.
Xꢀray powder patterns
were measured in a Guinier—Huber G670 chamber with a bent
germanium monochromator. On the Xꢀray powder patterns, poꢀ
sitions of the first 30 diffraction peaks were refined, which were
3
ꢀFluorobenzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7d)
15
16
17,18
used for indexing by the TREOR90, ITO, and AUTOX
programs. The crystal structure was solved by the simulated anꢀ
contains a fluorine atom in the molecule, which is prone
1
9
nealing method in the centrosymmetric group P2 /n. The soluꢀ
1
tion was looked for using a 3D molecular model obtained by
optimization with the density functional method using the
Table 1. Geometry of weak hydrogen bonds in the structure 7d
2
0
Priroda program. The solution found was further refined by
2
1
D—H...A*
D—H H...A D...A
D—H...A
deg
the Rietveld method using the MRIA program, the peaks´
2
2
/
profiles were described by the modified Voigt function. In the
process of refinement, restrictions were imposed on permissible
deviations of interatomic distances in the molecule and planariꢀ
ty of the molecule. For nonhydrogen atoms, one general paraꢀ
meter of isotropic thermal vibrations was refined. Hydrogen
atoms were placed in the calculated positions and were not reꢀ
Å
C(10)—H(10)...O(21)i
C(12)—H(12)...O(19)
0.93 2.45 3.102(14)
0.93 2.27 3.190(14)
127
169
ii
Codes of symmetry: (i) 1 – x, 1 – y, 1 – z; (ii) –x, –1 – y, 1 – z.

742
Russ.Chem.Bull., Int.Ed., Vol. 63, No. 3, March, 2014
Gornostaev et al.
Table 2. Crystallographic data for 7d
2ꢀ(4ꢀFluoroanilino)ꢀ1,4ꢀnaphthoquinone (6d). pꢀFluoroꢀ
aniline (9.5 mL, 100 mmol) in ethanol (20 mL) was added to
1
,4ꢀnaphthoquinone (7.9 g, 50 mmol) in ethanol (60 mL), the
Parameter
Value
mixture was stirred at 50 C for 30 min and cooled. A cherryꢀred
Molecular formula
Crystal system
Space group
a/Å
b/Å
c/Å
C16H FN O
3
Monoclinic
precipitate was filtered off. The yield was 5.6 g (42%), m.p.
7
2
2
7
28
26
247—248 C (cf. m.p. 246—248 C, 244 C, 227 C ). The
1
28
P2 /n
H NMR spectrum completely agree with the literature data.
1
8.5315(11)
5.3291(12)
26.643(3)
98.89(2)
1196.8(3)
33
Found (%): C, 72.15; H, 3.70; N, 5.14. C16H10FNO . Calculatꢀ
2
1
ed (%): C, 71.91; H, 3.74; N, 5.24. H NMR, : 6.00 (s, 1 H,
H(3)); 7.29 (m, 2 H, H(3´), H(5´)); 7.42 (m, 2 H, H(2´), H(6´));
7.79 (t, 1 H, H(6), H(7), J = 7.5 Hz); 7.86 (t, 1 H, H(6), H(7),
J = 7.5 Hz); 7.95 (d, 1 H, H(5), H(8), J = 7.5 Hz); 8.06 (d, 1 H,

V/Å
/deg
3
M20
*
H(5), H(8), J = 7.5 Hz); 9.25 (s, 1 H, NH). MS, m/z (I (%)):
rel
+
F30
*
45 (0.008, 47)
4
267 [M] (97.70), 238 (44.94), 105 (46.85), 104 (38.54), 76 (67.37),
Z
75 (45.55), 44 (62.46), 40 (100), 32 (96.90), 29 (48.95). UVꢀvis,
max/nm (log): 273 (4.36), 464 (3.56).
–
3
D /g cm
1.633
x
Irradiation
Wavelength/Å
CuꢀK1
1.5406
Benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxides 7a—d. Nitrosylsulꢀ
furic acid (prepared from NaNO (1.38 g, 20 mol) and concenꢀ
2
Xꢀray powder pattern: 2min – 2max
4.00—75.00
(0.01)
0.0187
0.0238
0.0182
trated H SO (10 mL)) was added dropwise to a solution of the
2
4
(
step of measurements/deg)
corresponding 2ꢀarylaminoꢀ1,4ꢀnaphthoquinone 6a—d (10 mmol)
in glacial acetic acid (50 mL) over 10 min. The reaction mixture
was stirred for 1 h and treated with water (30 mL); a yellow
precipitate was separated by filtration. The product was crystalꢀ
lized from toluene.
R *
p
Rwp
*
R

exp*
*
2
01.01.26
Benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7a). The yield was
2.5 g (91%), m.p. >300 C. Found (%): C, 69.37; H, 2.73; N, 10.13.
*
Indicators of indexing quality M and F were deterꢀ
20 30
2
3,24
2
25
mined in the works
; R , Rwp, R , and  in the work.
p exp
C H N O . Calculated (%): C, 69.57; H, 2.92; N, 10.14.
16 8 2 3
1
H NMR (DMSOꢀd ), : 7.94 (t, 1 H, H(2), J = 7.4 Hz); 8.00
6
(
m, 2 H, H(8), H(9)); 8.10 (t, 1 H, H(3), J = 7.4 Hz); 8.24 (d, 2 H,
fined. The principal crystallographic and experimental parameters
for 7d are given in Table 2. Figure 3 shows the experimental and the
differential curves resulted from the refinement by the Rietveld
method. The crystal structure 7d was deposited with the Camꢀ
bridge Structural Database under the reference CCDC 932752.
H(7), H(10), J = 7.8 Hz); 8.38 (d, 1 H, H(4), J = 8.4 Hz); 8.56
(
2
7
3
C=N); 1270 (N —O ).
ꢀMethylbenzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7b). The
yield was 2.5 g (86%), m.p. >300 C. Found (%): C, 70.29; H, 3.39;
+
d, 1 H, H(1), J = 8.4 Hz). MS, m/z (Irel (%)): 276 [M] (25.03),
60 (36.04), 232 (15.52), 204 (27.83), 104 (100), 76 (99.50),
5 (25.93), 50 (51.85). UVꢀvis, max/nm (log): 268 (4.47),
–
1
05 (4.42). IR, /cm : 1688, 1663 (C=O); 1588, 1573 (C=C,
2
ꢀArylaminoꢀ1,4ꢀnaphthoquinones (6a—c) were obtained
+
–
2
6,27
according to the known procedure,
their physicochemical
3
characteristics agree with those found earlier.
N, 9.73. C17H10N O . Calculated (%): C, 70.34; H, 3.47; N, 9.65.
2
3
I (rel. units)
1
H NMR (DMSOꢀd ), : 2.65 (s, 3 H, Me); 7.95 (m, 2 H, H(2),
6
H(8)); 7.99 (t, 1 H, H(9), J = 8.7 Hz); 8.23 (d, 1 H, H(10),
J = 8.7 Hz); 8.25 (d, 1 H, H(7), J = 8.7 Hz); 8.28 (d, 1 H, H(1),
J = 8.5 Hz); 8.38 (br.s, 1 H, H(4)). MS, m/z (Irel (%)): 290 [M]+
2
1
000
000
0
(
4
11.31), 274 (100), 246 (50.25), 218 (20.02), 104 (82.48), 76 (83.58),
3 (35.04). UVꢀvis, max/nm (log): 268 (4.47), 313 (4.41).
ꢀChlorobenzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7c). The
×
3
3
yield was 2.5 g (81%), m.p. >300 C. Found (%): C, 62.07;
H, 2.32; N, 8.72. C H ClN O . Calculated (%): C, 61.85;
1
6
7
2
3
1
H, 2.27; N, 9.02. H NMR (DMSOꢀd ), : 7.95 (td, 1 H, H(8),
6
J = 1.4 Hz, J = 7.4 Hz); 8.00 (td, 1 H, H(9), J = 1.4 Hz,
J = 7.4 Hz); 8.14 (dd, 1 H, H(2), J = 2.3 Hz, J = 8.9 Hz); 8.25
1
(
dt, 2 H, H(7), H(10), J = 1.4 Hz, J = 7.4 Hz); 8.43 (d, 1 H,
H(1), J = 8.9 Hz); 8.58 (d, 1 H, H(4), J = 2.3 Hz). MS, m/z
+
+
(
(
Irel (%)): 312 [M + 2] (13.51), 311 [M + 1] (4.90), 310 [M]+
2
27.83), 296 (39.24), 295 (18.22), 294 (100), 268 (22.72),
1
0
20
30
40
50
60
2/deg
2
67 (10.01), 266 (69.17), 240 (17.62), 238 (40.94), 110 (30.93),
Fig. 3. The result of refinement of crystal structure 7d by the
Rietveld method: 1 is the experimental curve; 2 is the difference
between experimental and calculated curves as a result of refineꢀ
ment. The highꢀangle region (2 > 30) is shown magnified.
The calculated positions of reflections are shown by vertical segꢀ
ments.
105 (39.54), 104 (49.35), 76 (14.71), 75 (67.47), 74 (20.12),
58 (37.24), 43 (25.53). UVꢀvis, max/nm (log): 268 (4.48),
316 (4.43).
3ꢀFluorobenzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7d). The
yield was 2.4 g (82%), m.p. > 300 C. Found (%): C, 65.37;
H, 2.35; N, 9.41. C16H FN O . Calculated (%): C, 65.31;
7
2
3

Synthesis of benzo[b]phenazineꢀ6,11ꢀdioneꢀ12ꢀoxdes Russ.Chem.Bull., Int.Ed., Vol. 63, No. 3, March, 2014
743
1
H, 2.38; N, 9.52. H NMR, : 7.95 (td, 1 H, H(8), J = 1.4 Hz,
J = 7.5 Hz); 8.00 (td, 1 H, H(9), J = 1.4 Hz, J = 7.5 Hz); 8.07 (td,
4. C. Baltzer, Chem. Ber., 1881, 14, 1899.
5. T. Win, S. Yerushalmi, S. Bittner, Synthesis, 2005, 1631.
1
H, H(2), J = 2.8 Hz, J = 9.0 Hz); 8.25 (dt, 2 H, H(7), H(10),
J = 1.4 Hz, J = 7.5 Hz); 8.34 (dd, 1 H, H(4), J = 2.8 Hz, JCH,F
9.0 Hz); 8.52 (dd, 1 H, H(1), J = 5.4 Hz, J = 9.0 Hz). MS,
6. K. Fries, K. Billig, Ber. Deutsch. Chem. Ges., 1925, 58, 1128.
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cheniya, 2011, 26, No. 11, 61].
9. A. L. Spek, Acta Crystallogr. Sect. D, 2009, D65, 148.
10. F. H. Allen, Acta Crystallogr. Sect. B, 2002, B58, 380.
11. C. F. Macrae, I. J. Bruno, J. A. Chisholm, P. R. Edgington,
P. McCabe, E. Pidcock, L. RodriguezꢀMonge, R. Taylor,
J. van de Streek, P. A. Wood, J. Appl. Crystallogr., 2008,
41, 466.
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33, 526.
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A64, 52.
=
=
CH,F
m/z (Irel (%)): 294 [M]+ (41.64), 278 (53.75), 250 (26.03), 222
35.24), 104 (100), 76 (69.57), 50 (27.23), 32 (83.48). UVꢀvis,
(
max/nm (log): 268 (4.47), 310 (4.40).
Benzo[b]phenazineꢀ6,11ꢀdione (4a). A solution of hydrazine
hydrate (0.5 mL) in ethanol (5 mL) was added to a solution of
benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7a) (0.276 g, 1 mmol)
in DMF (10 mL) using a dropping funnel over 20 min at 20 C.
After 1 h, a light green precipitate of phenazinequinone was
formed, which was filtered off and crystallized from DMF. The
yield was 0.23 g (89%), m.p. 333—334 C. Found (%): C, 73.71;
H, 3.02; N, 10.72. C16H N O . Calculated (%): C, 73.85;
8
2
2
1
H, 3.08; N, 10.77. H NMR, : 8.01 (m, 2 H, H(8), H(9)); 8.13
m, 2 H, H(2), H(3)); 8.34 (m, 2 H, H(7), H(10)); 8.42 (m, 2 H,
H(1), H(4)). MS, m/z (Irel (%)): 260 [M]+ (51.75), 232 (22.22),
04 (25.03), 104 (97.00), 76 (100), 75 (30.83), 50 (63.46). UVꢀvis,
(
2
max/nm (log): 287 (4.41). IR, /cm– : 1688 (C=O; 1591
1
(
C=C, C=N).
15. P.ꢀE. Werner, L. Eriksson, M. Westdahl, J. Appl. Crystalꢀ
logr., 1985, 18, 367.
3
ꢀ(Morpholinꢀ4ꢀyl)benzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide
(
3
9). Morpholine (0.2 mL, 2 mmol) was added to a solution of
ꢀfluorobenzo[b]phenazineꢀ6,11ꢀdione 5ꢀoxide (7d) (1 mmol)
16. J. W. Visser, J. Appl. Crystallogr., 1969, 2, 89.
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25, 447.
in DMF (20 mL). The mixture was stirred for 2 h at 40 C and
cooled to 20 C, a red precipitate was separated by filtration. The
product was crystallized from toluene. The yield was 0.37 g (94%),
m.p. 290—292 C. Found (%): C, 66.10; H, 4.04; N, 11.31.
C
20H15N O . Calculated (%): C, 66.48; H, 4.16; N, 11.63.
3 4
1
H NMR, : 3.55 (br.s, 4 H, N(CH ) ); 3.80 (br.s, 4 H, O(CH ) );
2
2
2 2
7
.63 (s, 1 H, H(4)); 7.86 (br.d, 1 H, H(2), J = 9.6 Hz); 7.89 (t, 1 H,
H(8), J = 8.2 Hz); 7.93 (t, 1 H, H(9), J = 8.2 Hz); 8.12 (d, 1 H,
22. H. Toraya, J. Appl. Crystallogr., 1986, 19, 440.
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H(1), J = 9.6 Hz); 8.20 (d, 1 H, H(7), H(10), J = 8.2 Hz); 8.22
+
(
(
d, 1 H, H(7), H(10), J = 8.2 Hz). MS, m/z (Irel (%)): 361 [M]
5.51), 345 (25.33), 287 (33.03), 104 (100), 76 (85.79), 50 (22.42),
4
4 (23.32), 32 (92.59), 29 (29.03). UVꢀvis, max/nm (log): 270
(
4.51), 326 (4.24), 455 (4.13).
[
CAPLUS AN 1965:66995].
2
2
7. C. S. Lisboa, V. G. Santos, B. G. Vaz, N. C. Lucas, M. N.
Eberlin, S. J. Garden, J. Org. Chem., 2011, 76, 5264.
8. E. Leyva, L. I. Lopez, S. E. LoredoꢀCarrillo, M. Rodriguezꢀ
Kessler, A. MontesꢀRojas, J. Fluor. Chem., 2011, 132, 94.
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2
3
Received July 22, 2013;
1
963, 28, 520.
in revised form December 6, 2013