Synthesis, nature of electronic transitions, and absorption spectra of the dye based on 4-(methyl-1-{2-[4-(1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)phenyl]-2-oxoethyl}pyridinium bromide

Article abstract of DOI:10.1134/S1070363216080107

The reaction of 3-(4-bromoacetylphenyl)-1-methylquinolin-2(1Н)-one with pyridine and 4-methylpyridine has afforded the corresponding pyridinium salts. Condensation of 4-methyl-1-{2-[4-(1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)phenyl]-2-oxoethyl}pyridinium

Full text of DOI:10.1134/S1070363216080107

ISSN 1070-3632, Russian Journal of General Chemistry, 2016, Vol. 86, No. 8, pp. 1838–1844. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © О.V. Yelenich, R.Z. Lytvyn, O.V. Skrypska, Kh.Ye. Pitkovych, A.D. Kachkovskiі, M.D. Obushak, P.I. Yagodinets, 2016, published in
Zhurnal Obshchei Khimii, 2016, Vol. 86, No. 8, pp. 1299–1305.
Synthesis, Nature of Electronic Transitions,
and Absorption Spectra of the Dye Based
on 4-(Methyl-1-{2-[4-(1-methyl-2-oxo-1,2-dihydroquinolin-
3
-yl)phenyl]-2-oxoethyl}pyridinium Bromide
a
b
a
b
О. V. Yelenich , R. Z. Lytvyn , O. V. Skrypska , Kh. Ye. Pitkovych ,
c
b*
a
A. D. Kachkovskiі , M. D. Obushak , and P. I. Yagodinets
a
b
Chernivtsi National University, Lesya Ukrainka Street 25, Chernivtsi, 58012 Ukraine
Ivan Franko National University of Lviv, Kirila i Mefodiya ul. 6, Lviv, 79005 Ukraine
*
e-mail: obushak@in.lviv.ua
c
Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Kyiv, Ukraine
Received January 28, 2016
Abstract—The reaction of 3-(4-bromoacetylphenyl)-1-methylquinolin-2(1Н)-one with pyridine and 4-methyl-
pyridine has afforded the corresponding pyridinium salts. Condensation of 4-methyl-1-{2-[4-(1-methyl-2-oxo-
1
,2-dihydroquinolin-3-yl)phenyl]-2-oxoethyl}pyridinium bromide with 4-dimethylaminobenzaldehyde has
given a new biscyanine dye, 1-{1-[4-(1,2-dihydro-1-methyl-2-oxo-3-quinolinyl)benzoyl]-2-[4-(dimethylamino)-
phenyl]ethynyl}-4-{2-[4-(dimethylamino)phenyl]ethynyl}pyridinium bromide. Its electronic spectrum has
been analyzed, and quantum-chemical simulation of spatial and electronic structure of its possible isomers has
been performed.
Keywords: quinolin-2-one, pyridinium salt, cyanine dye, electronic absorption spectra, quantum-chemical simulation
DOI: 10.1134/S1070363216080107
Quaternary salts of methyl derivatives of pyridine
and quinoline are often used for preparation of cyanine
dyes [1]. The interest to investigation of bis-cyanine
dyes, besides the practical aspect, is caused by special
features of the interaction between the two chromo-
phores. The nature of this interaction has been
described in [1–4].
ethyl)pyridinium bromide, and its spatial structure has
been elucidated by means of analysis of absorption
spectra and the nature of electronic transitions [8].
In this work, we synthesized for the first time bis-
cyanine 7 with the quinolone core based on quaternary
salt 6, the latter containing a benzene ring and a
carbonylmethyl group between the quinolone and
pyridine rings. Salt 6 was obtained via a sequence of
transformations 3→4→6 (Scheme 1). The Meerwein
reaction of 1-methylquinolin-2(1Н)-one 1 with 4-
acetylphenyldiazonium chloride 2 afforded the sub-
stituted 1-methylquinolin-2(1Н)-one 3. Its bromination
in acetic acid gave bromoketone 4, which formed
quaternary salts 5 and 6 upon heating with pyridine or
4-methylpyridine in toluene, respectively.
Cyanine dyes with two conjugated chromophores
based on 1-[2-oxo-2-(coumarin-3-yl)ethyl]-4-methyl-
pyridinium bromide have been earlier synthesized, and
their spectral properties have been investigated [5].
Using the example of a similar 4-methylquinolinium
salt, spatial arrangement of the chromophores in the
bis-cyanine dye has been analyzed by means of elec-
tronic absorption spectroscopy and quantum-chemical
simulations [6, 7].
The C=O group absorption band in the IR spectra
–
1
Recently, a bis-cyanine dye has been obtained via
condensation of 4-dimethylaminobenzaldehyde with 4-
methyl-1-(2-oxo-2-[4-(2-oxo-2Н-chromen-3-yl)phenyl]-
of salts 5 and 6 appeared at 1690–1700 cm , and the
absorption band of the cyclic amide group was
–
1
observed at 1630–1650 cm .
1
838

SYNTHESIS, NATURE OF ELECTRONIC TRANSITIONS, AND ABSORPTION SPECTRA
1839
Scheme 1.
O
O
Br
+
N
Cl
CH3
2
Br2
CuCl2
+
O
AcOH
Py
N
N
N
O
O
CH3
CH3
CH3
O
CH3
IV
4
I
II
2
3
III
1
O
4-MePy
O
+
N
+
N
Br
Br
N
O
N
O
CH3
CH3
V5
6V I
Scheme 2.
O
O
Br
N
+
O
NMe2
Br
N
+
NMe2
2
N
O
CH3
N
O
(CH CO) O
3 2
CH3
VII
VI
NMe2
6
7
It was shown that salt 6 in acetic anhydride par-
ticipated in the cyanine condensation with 4-dimethyl-
aminobenzaldehyde both at the methyl and the
methylene groups with the formation of bis-cyanine
dye 7 (Scheme 2). The reactivity of the methylene
group in quaternary salt 6 was due to the presence of
two electron-acceptor centers in the molecule:
quaternary nitrogen atom and carbonyl group.
at different fragments of the molecule, we synthesized
two types of “parent” monocyanines based on pyridi-
nium salts, containing only one active methylene or
methyl group. The use of salt 5 in condensation with 4-
dimethylaminobenzaldehyde gave monocyanine 8 of
the first type (Scheme 3); its spectrum was charac-
terized by the absorption maximum at 436 nm.
In one of the earlier works [5], pyridinium salt 9
Electronic absorption spectrum of bis-cyanine 7
contained two absorption bands: a stronger short-wave
one at 432 nm (log ε 4.08) and a weaker long-wave
one at 506 nm (log ε 3.84).
has been obtained via the reaction of 1-chloro-
methylnaphthalene
with
4-methylpyridine;
its
transformation afforded the “parent” monocyanine dye
10 (Scheme 4). The spectrum monocyanine 10 con-
tained the absorption band with maximum at 492 nm.
In order to confirm that the appearance of two
bands in the absorption spectra of the bis-cyanine dye
was caused by the interaction of chromophores linked
The choice of salt 9 for the synthesis of mono-
cyanine of the second type was due to the following
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 8 2016

1
840
YELENICH et al.
Scheme 3.
O
C
O
C
Br
O
N
+
Br
NMe2
N
+
NMe2
N
O
(CH CO) O
N
3
2
O
CH3
CH3
VI
VIII
8
5
Scheme 4.
O
Br
NMe2
Br
NMe2
+
N
+
N
9
IX
10
X
considerations. A hardly available 3-(4-bromomethyl)-
-methylquinolone (not mentioned in the reference
phores marginally affect each other. If the two
chromophores absorb radiation of similar frequency,
then, being conjugated, they influence each other in
such a way that the absorption bands become more
separated in the spectrum.
1
literature) was required for preparation of the similar
quinolone-containing salt. On the other hand, taking
into account a partially blocked transfer of electronic
effects by methylene group [9], we suggested that the
absorption maximums of styryl dyes containing
naphthalene or quinolone fragments would not be
substantially different.
In order to determine the spatial structure of the bis-
cyanine, we calculated the angle between the planes of
chromophores (78°) using the earlier described method
[11]. The degree of interaction of the chromophores
Hence, two maximums of absorption bands of dye
was determined from the Δ –Δ difference [4] (Δ , the
2
1
2
7
revealed a hypsochromic shift by 4 nm and batho-
difference of maximums of two absorption bands of
chromic shift by 14 nm, respectively, as compared to
the bands of the “parent” dyes 8 and 10 containing a
single chromophore each.
the bis-cyanine dye and Δ , the difference of
absorption maximums of the two “parent” dyes),
Δ –Δ = 18 nm. The obtained value reflects the degree
2 1
1
of mobility (delocalization) of π-electrons in the
polymethine chromophores: the larger the electron
delocalization, the stronger the chromophores interact.
A more prominent shift of the long-wave maximum
as compare to the short-wave one is explained by the
difference in the degree of delocalization of π-
electrons in polymethine chromophores of “parent”
dyes 8 and 10. The longer the polymethine chain, the
stronger delocalization of these electrons and the
stronger the interaction with another chromophore [4].
We have earlier shown [7] that for the model dye
with a hydrogen atom instead of the carbonylphenyl-
quinolone moiety, four structures are possible,
differing in the geometry of the styryl linkages. For the
molecule of dye 7, the number of possible isomers was
higher due to substantial steric hindrances. We
performed quantum-chemical simulation of the
equilibrium geometry and electronic structure of the
possible isomers.
The nature of interaction of the chromophore
systems in the molecule of the dye, and, hence, of the
opposite shifts of the absorption bands can be
considered based on the perturbation theory and its
application to electronic spectra [4, 10]. If the
molecule of a cyanine contains two conjugated
chromophores which (each separately in the “parent”
dyes) absorb light of different energy, such chromo-
Of the possible isomers of the dye, we chose the
most stable one, with its theoretical spectrum being the
closest to the experimental one. Optimization of the
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 8 2016

SYNTHESIS, NATURE OF ELECTRONIC TRANSITIONS, AND ABSORPTION SPECTRA
1841
Е, eV
Fig. 1. Optimized spatial structure of dye 7; dihedral angles
between the fragments are shown separately in the inset.
molecular geometry (Fig. 1) was performed using a
DFT/6-31G(d,p) method, and parameters of the
Fig. 2. Scheme of electronic transitions in dye 7; low-
electronic transitions were determined using a ТD DFТ
simulation with the same basis set (GAUSSIАN 03
software suite [12]). As shown in Fig. 1, three planar
fragments were found in the molecule, oriented at a
substantial angle with respect to each other. However,
the simulation was indicative of a substantial
interaction between the fragments, suggesting that the
molecule of the dye had a common π-system. Figure 2
shows the shape of the boundary orbitals and certain
close to them ones, contributing to the lower electronic
transitions reflected in the experimental absorption
spectrum. Due to branching of the common
chromophore of dye 7 into three fragments, the pattern
of electronic transitions was more complex than in the
simple classical scheme of chromophores interaction
intensity transitions are marked by dotted arrows.
р-th excited state Ψ in the method of configuration
p
interaction (Ψ = ΣT Ф ,) with summation over all
p
p,i→j i→j
configurations, indices i and j pointing at the orbitals
participating in the transition [13]. The most important
configurations of the molecule involved in these
transitions are depicted in Fig. 2. Analysis of the
simulated parameters of electronic transitions and of
the experimental absorption spectrum showed that the
first spectral band corresponded to two electronic
transitions S →S and S →S , with the oscillator
0
4
0
6
strengths f 0.844 and f 0.807. The ratio of the
4
6
calculated oscillator strengths for those transitions f4
[4, 11] assuming a uniform delocalization of the
and f was close to the oscillator strength for the long-
6
orbitals over the whole molecule of biscyanine.
wave electronic transition S →S involving HOMO
0
1
and LUMO, equal to f1 1.724. Note that the
experimental position of the long-wave absorption
band coincided with the theoretically calculated one.
The Table lists the parameters of transitions
simulated in the ZINDO approximation. The
contributions from the major configurations Фi→j given
in the Table as well were quantitatively estimated by
coefficient Tp,i→j in the expansion of the function of the
Besides those transitions of relatively high
intensity, the simulation also predicted the transitions
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 8 2016

1
842
YELENICH et al.
–
5
Simulated parameters of electronic transitions in compound
7
tion spectra (2 × 10 mol/L solutions in ethanol) were
a
1
recorded using an SF-46 spectrophotometer. Н NMR
spectra were recorded using a Varian Mercury
λ
nm
max
,
Contribution of configurations,
Transition
f
spectrometer 400 (400 MHz) in DMSO-d or CDCl ,
6
3
T
p,i→j
with TMS as internal reference. Melting points were
determined using a Boetius hot plate.
S
0
→ S
1
506
430
1
1.724 |S > = 0.68 |HOMO→LUMO>
–
–
0.45 |HOMO-1→LUMO>
0.41 |HOMO-2→LUMO>
4
-Acetylphenyldiazonium chloride (2). A mixture
of 6.8 g (0.05 mol) of 4-aminoacetophenone, 32 mL of
conc. HCl, and 18 mL of water was heated to boiling.
The obtained solution was cooled to 0–5°С and kept at
that temperature for 5 min; 4-aminoacetophenone hydro-
chloride precipitated. A solution of 4 g (0.058 mol) of
sodium nitrite in 14 mL of water was added dropwise
at vigorous stirring and cooling to the obtained
S
0
→ S
2
2
0.112 |S > = 0.49 |HOMO-
3
–
→LUMO>
0.31 |HOMO-3→LUMO+1>
S
S
0
0
→ S
→ S
3
4
416
387
0.106 |S
3
> = 0.42 |HOMO→LUMO>
0
.42 |HOMO-2→LUMO>
0.844 |S > = 0.59
HOMO→LUMO+1>
4
suspension. After addition of NaNO , the reaction
2
|
mixture was kept for 15 min in an ice bath. The
obtained solution was filtered, and the filtrate was
neutralized with saturated solution of sodium acetate to
рН 6.
0
–
.44 |HOMO-1→LUMO+1>
0.30 |HOMO-2→LUMO>
S
S
0
0
→ S
→ S
5
6
366
359
0.028 |S
HOMO→LUMO+1>
0.42 |HOMO-1→LUMO+1>
0.807 |S > = 0.59 |HOMO-
5
> = 0.29
|
–
3
-(4-Acetylphenyl)-1-methylquinolin-2(1Н)-one
(
3). The reaction was carried out in a flask equipped
6
with a thermometer, a bubble counter for evolved gas,
and a dropping funnel. A cooled solution of 4-
acetyldiazonium chloride 2 prepared by diazotization
of 0.05 mol of aminoacetophenone was added drop-
wise (so that the nitrogen evolution was not too
vigorous) to a mixture of 8 g (0.05 mol) of 1-methyl-
1
–
→LUMO+1>
0.41 |HOMO-2→LUMO+1>
a
(
λ) wavenumber of transition; (f) oscillator strength; (Tp,i→j
coefficient of the configuration contribution.
)
S →S , S →S and S →S in that spectral region, but
0
2
0
3
0
5
they did not appear in the spectrum as separate bands
because of low oscillator strengths (low intensities) but
were rather masked by the bands of stronger
transitions. Overall, the analysis of the simulated and
experimental data showed that the observed absorption
spectrum corresponded to the isomer depicted in Fig.
carbostyryl 1, 0.6 g (3.5 mmol) of СuСl ·2Н О, and
2 2
60 mL of acetone. After nitrogen evolution had ceased,
the formed precipitate was filtered off, washed with
water, dried, and recrystallized from ethanol. Yield
1
2.5 g (32%), mp 154–155°С. H NMR spectrum
(CDCl
NCH ), 7.26 t (1Н, quinolone, J = 7.8 Hz), 7.38 d (1Н,
quinolone, J = 7.8 Hz), 7.57–7.62 m (2Н, Ar), 7.79–
7.86 m (3Н, Ar), 8.00 d (2Н, С , J = 7.0 Hz). Found,
. Calculated,
), δ, ppm: 2.62 s (3Н, СН СO), 3.78 s (3Н,
3
3
1
. Two strong bands usually appear in the spectra of
3
conventional biscyanine dyes, sometimes with the
bands of weaker transitions in between, corresponding
to the electron density transfer between the fragments
of the molecule due to different localization of the
boundary orbitals and close to them ones.
Н
4
6
%: С 77.83; Н 5.30; N 4.97. С18
%: С 77.95; Н 5.45; N 5.05.
Н15NО
2
3-(4-Bromoacetylphenyl)-1-methylquinolin-2(1Н)-
In summary, modification of chromophore of the
biscyanine dye by introduction of new conjugated
fragments complicates the pattern of its electronic
transitions, although the two split intense bands are
still observed in the spectrum; they are sensitive to the
change in chemical structure of the dye molecule.
one (4). 0.52 mL (0.01 mol) of bromine was added
dropwise at 90°С to a solution of 2.77 g (0.01 mol) of
compound 3 in 100 mL of acetic acid. The solution
was cooled and poured into 100 mL of water. The
formed precipitate was filtered off, washed with water,
dried, and recrystallized from aqueous ethanol. Yield
1
3
.20 g (90%), mp 166–167°С. H NMR spectrum
EXPERIMENTAL
(
CDCl ), δ, ppm: 3.79 s (3Н, NCH ), 4.48 s (2Н, CH ),
3 3 2
IR spectra (KBr pellets) were registered using a
Specord IR-75 spectrophotometer. Electronic absorp-
7.28 t (1Н, quinolone, J = 7.4 Hz), 7.39 d (1Н,
quinolone, J = 8.2 Hz), 7.59–7.64 m (2Н, Ar), 7.84–
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 8 2016

SYNTHESIS, NATURE OF ELECTRONIC TRANSITIONS, AND ABSORPTION SPECTRA
1843
7
.90 m (3Н, Ar), 8.02 d (2Н, С Н , J = 8.2 Hz). Found, 70.56; Н 5.39; N 7.73. C H BrN O . Calculated, %:
6
4
42 39
4
2
%
: С 60.74; Н 4.09; Br 22.15. C H BrNO .
С 70.88; Н 5.52; N 7.87.
1
8
14
2
Calculated, %: С 60.69; Н 3.96; Br 22.43.
1-{1-[4-(1,2-Dihydro-1-methyl-2-oxo-3-quinolinyl)-
Pyridinium salts 5, 6. A mixture of 0.71 g
2 mmol) of compound 4 and 0.16 g (2 mmol) of
benzoyl]-2-(4-dimethylaminophenyl)ethynyl}pyri-
dinium bromide (8). A mixture of 0.21 g (0.5 mmol)
of salt 5 and 0.075 g (0.5 mmol) of 4-dimethyl-
aminobenzaldehyde in 7 mL of acetic anhydride was
refluxed for 1 h. The reaction mixture was cooled and
treated with diethyl ether. The precipitated dye was
filtered off. Yield 0.18 g (63%), mp 185–187°С
(
pyridine or 0.19 g (2 mmol) of 4-methylpyridine was
refluxed in 20 mL of dry toluene for 15–30 min and
kept for 12 h at room temperature. The formed
precipitate was filtered off, washed with diethyl ether,
and dried.
(
decomp.) (precipitated with ether from isopropanol).
1
-{2-[4-(1-Methyl-2-oxo-1,2-dihydroquinolin-3-
1
H NMR spectrum (DMSO-d ), δ, ppm: 2.98 s (6H,
NMe
7
6
yl)phenyl]-2-oxoethyl}pyridinium bromide (5).
Yield 0.65 g (75%), mp 228–230°С (butanol). Н
NMR spectrum (DMSO-d ), δ, ppm: 3.73 s (3Н,
1
2 6 4 2
), 3.75 s (3H, NMe), 6.63 d (2H, C H NMe , J =
.6 Hz), 6.69 d (2H, C H NMe , J = 7.6 Hz), 7.35 t
6
4
2
6
(
1H, quinolone, J = 7.6 Hz), 7.61 d (1Н, quinolone, J =
.5 Hz), 7.69 t (1Н, quinolone, J = 7.7 Hz), 7.84–7.89
m (2Н, Ar), 7.96 d (2Н, С Н , J = 8.2 Hz), 8.02 d (2Н,
CH N), 6.57 s (2Н, CH ), 7.34 t (1Н, quinolone, J =
3
2
8
7
.8 Hz), 7.60 d (1Н, quinolone, J = 8.2 Hz), 7.69 t (1Н,
quinolone, J = 7.8 Hz), 7.87 d (1Н, quinolone, J =
.8 Hz), 8.04 d (2Н, Ar, J = 8.6 Hz), 8.13 d (2Н, Ar,
J = 8.6 Hz), 8.27–8.33 m (3Н, Ar), 8.76 t (1Н, 4-НPy,
J = 7.8 Hz), 9.06 d (2Н, 2,6-Н , J = 5.5 Hz). Found,
6
4
С Н , J = 8.1 Hz), 8.30 s (1H, CH), 8.46–8.50 m (2Н,
C H N), 8.96 t (1Н, C H N, J = 7.8 Hz), 9.33 d (2Н,
C H N, J = 5.6 Hz). Found, %: С 67.67; Н 4.85; N
7
6
4
7
5
5
5
5
5
5
Py
.29. С Н BrN O . Calculated, %: С 67.85; Н 4.98;
32 28 3 2
%
: С 63.83; Н 4.52; N 6.28. C H BrN O . Cal-
23 19 2 2
N 7.42.
culated, %: С 63.46; Н 4.40; N 6.44.
-Methyl-1-{2-[4-(1-methyl-2-oxo-1,2-dihydro-
quinolin-3-yl)phenyl]-2-oxoethyl}pyridinium bromide
REFERENCES
1. Kiprianov, A.I., Tsvet i stroenie tsianinovykh krasitelei
4
1
(Color and Structure of Cyanine Dyes), Kiev: Naukova
(
6). Yield 0.77 g (86%), mp 248–250°С (butanol). Н
NMR spectrum (DMSO-d ), δ, ppm: 2.70 s (3Н, СН ),
Dumka, 1979.
6
3
3
.74 s (3Н, CH N), 6.49 s (2Н, CH ), 7.35 t (1Н,
2. Il’chenko, A.Ya., Osnovy teorii tsvetnosti organi-
cheskikh krasitelei (Basics of Organic Dyes Color
Theory), Kiev: Naukova Dumka, 2012.
3
2
quinolone, J = 7.8 Hz), 7.61 d (1Н, quinolone, J =
.2 Hz), 7.70 t (1Н, quinolone, J = 7.8 Hz), 7.87 d (1Н,
quinolone, J = 7.8 Hz), 8.04 d (2Н, С Н , J = 8.2 Hz),
8
3
. Kachkovskii, A.D., Stroenie i tsvet polimetinovykh
krasitelei (Structure and Color of Polymethine Dyes),
Kiev: Naukova Dumka, 1989.
6
4
8
.09–8.16 m (4Н, Ar), 8.32 s (1Н, quinolone), 8.88 d
(
2Н, 2,6-Н , J = 5.9 Hz). Found, %: С 63.84; Н 4.56;
Py
4
5
6
7
8
. Kiprianov, A.I., Russ. Chem. Rev., 1971, vol. 40, no. 7,
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no. 11, p. 2114. doi 10.1134/S1070363214110127.
N 6.19. C H BrN O . Calculated, %: С 64.15; Н 4.71;
24
21
2
2
N 6.23.
-{1-[4-(1,2-Dihydro-1-methyl-2-oxo-3-quinolinyl)-
benzoyl]-2-[4-(dimethylamino)phenyl]-ethynyl}-4-
2-[4-(dimethylamino)phenyl]ethynyl}pyridinium
1
{
bromide (7). A mixture of 0.22 g (0.5 mmol) of
pyridinium salt 6 and 0.15 g (1 mmol) of 4-dimethyl-
aminobenzaldehyde in 7 mL of acetic anhydride was
refluxed for 75 min, the reaction mixture was cooled
and treated with diethyl ether. The precipitated dye
was filtered off. Yield 0.15 g (42%), mp > 270°С (pre-
1
cipitated with ether from isopropanol). H NMR spec-
trum (DMSO-d ), δ, ppm: 2.95 s (6H, NMe ), 3.05 s
9. Pridan, V.E., Chernyuk, I.N., Rogovik, L.I., and
Bukachuk, O.M., Zh. Org. Khim., 1980, vol. 16, no. 9,
p. 1973.
6
2
(
6H, NMe ), 3.74 s (3H, NMe), 6.61–6.69 m (4Н, Ar),
2
6
.81–6.90 m (4Н, Ar), 7.30–7.38 m (2Н), 7.61–8.03 m
10. West, W., Chemical Applications of Spectroscopy,
(
8Н), 8.26–8.34 m (2Н), 8.87 d (2H, C H N, J =
Interscience Publishers, 1956.
5
5
5
.6 Hz), 9.13 d (2H, C H N, J = 5.6 Hz). Found, %: С
11. Kiprianov, A.I. and Dyadyusha, G.G., Ukr. Khim. Zh.,
5
5
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 8 2016

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