An effective synthesis of polynuclear tetraamines, monomers for polyheteroarylenes

Article abstract of DOI:10.1007/s11172-018-2182-8

An effective synthesis of polynuclear tetraamines via nucleophilic substitution of chlorine in 2-chloro-5-nitroaniline under ultrasonic irradiation followed by catalytic hydrogenation of dinitrodiaminoarenes in a flow reactor was proposed. A number of mon

Full text of DOI:10.1007/s11172-018-2182-8

Russian Chemical Bulletin, International Edition, Vol. 67, No. 6, pp. 1072—1077, June, 2018
1072
An effective synthesis of polynuclear tetraamines,
monomers for polyheteroarylenes
R. S. Begunov,a A. N. Valyaeva,a A. A. Bashkirova,a N. M. Belomoina,b and E. G. Bulychevab
aP. G. Demidov Yaroslavl State University,
14 ul. Sovetskaya, 150003 Yaroslavl, Russian Federation.
Fax: +7 (485) 279 7751. E-mail: begunov@bio.uniyar.ac.ru
bA. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
28 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (499) 135 5085
An effective synthesis of polynuclear tetraamines via nucleophilic substitution of chlorine
in 2-chloro-5-nitroaniline under ultrasonic irradiation followed by catalytic hydrogenation of
dinitrodiaminoarenes in a flow reactor was proposed. A number of monomers, including those
not described in the literature, were thus obtained. Two classes of polyheteroarylenes, namely,
polynaphthoylenebenzimidazoles and polyphenylquinoxalines were synthesized by the polycy-
clocondensation in a supercritical carbon dioxide. Incorporation of trifluoromethyl substituents
and flexible oxygen bridges into the structure of monomers allowed one to improve the solubil-
ity of the polymers. Some properties of synthesized polyheteroarylenes were investigated.
Key words: polynuclear tetraamines, polyheteroarylenes, ultrasonic synthesis, aromatic
nucleophilic substitution, catalytic hydrogenation, supercritical carbon dioxide, polynaph-
thoylenebenzimidazoles, polyphenylquinoxalines.
Polynaphthoylenebenzimidazoles (PNBI) and poly-
group and the hydrolysis of the С—N bond in the acet-
amide substituent.
phenylquinoxalines (PPQ) are considered to be promising
polyheteroarylenes. They possess a complex of unique
properties, namely, thermal, heat, fire, and chemical sta-
bilities, high hydrolytic and radiation resistance, etc.1—4
Recently, various specific physical properties of these
polymers, which significantly expands their application in
high-technology areas, have been gradually revealed.5—8
The main reason that prevents their industrial synthe-
sis and wide application is the lack of a developed mono-
meric base. That is associated with the low efficiency of
the methods for the synthesis of high-purity monomers.
This relates primarily to the aromatic tetraamines. The
compounds containing a system of aromatic rings linked
together by bridging atoms or groups are the most interest-
ing between tetraamines. The presence of such structural
elements in polyheteroarylenes increases the flexibility of
the polymer chain, improves the solubility and process-
ability of polymers in the wares.9 The methods for the
synthesis of such monomers are multistage and ineffective.
In a number of cases, 4-chloronitrobenzene is used as the
basic structure.10 The reaction of 4-chloronitrobenzene
with a bisphenol leads to a polynuclear structure. Its fur-
ther functionalization by reduction and nitration reactions
allows the preparation of target tetraamines. Taking into
account that the introduction of the nitro group is usually
carried out in acidic media, two more steps are added to
the synthesis scheme, namely, the acylation of the NH2-
The use of 5-chloro-2-nitroaniline (1a) in the synthe-
sis is more attractive. This allows one to reduce significantly
the number of synthetic steps. An obstacle to the effective
application of this starting compound is its low reactivity
in the SNAr reaction.11 It was proposed to increase the
reactivity of the compound 1a by converting the amino
group to acetamide in order to accelerate the reaction of
aromatic nucleophilic substitution.12 Despite the fact that
pure aromatic tetraamines were obtained, for a number of
compounds posessing poor solubility carrying out acid
hydrolysis required a long time and high temperatures. All
this reduced the yield of diaminodinitroarenes.
We have developed an efficient two-stage synthesis of
high-purity polynuclear tetraamines in order to obtain new
PNBI and PPQ on their basis (Scheme 1). In this case,
both known tetraaminoarenes 4a,b and previously unde-
scribed monomers 4c,d have been synthesized. Due to a
presence of fluorine atoms the latter compounds are of
interest for the synthesis of PPQ with low dielectric per-
mittivity.5
Results and Discussion
As we have showed earlier,13 ultrasonic activation
significantly accelerates the SNAr reaction. This approach
was used to produce polynuclear diaminodinitroarenes
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1072—1077, June, 2018.
1066-5285/18/6706-1072 © 2018 Springer Science+Business Media, Inc.

Polynuclear tetraamines
Russ. Chem. Bull., Int. Ed., Vol. 67, No. 6, June, 2018
1073
Scheme 1
3a—d (see Scheme 1). The reaction was carried out in an
ultrasonic bath at 80 °С. The duration of the process was
more dependent on the nature of the electrophile (Table 1).
The yield of the products was 93—98%. Compounds 3a—d
did not require further purification. If we compare the
results obtained with the data of Ref. 14, where the syn-
thesis of 1,4-bis(3-amino-4-nitrophenoxy)benzene (3b)
is described, the use of ultrasound made it possible to
shorten the reaction time from 24 to 2 h, reduce the pro-
cess temperature from 140 to 80 °С, and increase the yield
of compound 3b from 83% to 93%.
The structure of the resulting polynuclear diamino
1
dinitro compounds was proved using Н and 19F NMR
spectroscopy, high-resolution mass spectrometry, and
1
1: R = H (a), CF3 (b);
elemental analysis. Figure 1 presents the Н NMR spec-
trum of the compound 3d with the assignment of proton
signals.
2: X =
(a),
(b),
(c);
The reduction of nitro groups in compounds 3a—d was
carried out under conditions of heterogeneous catalysis in
a flow-through hydrogenation reactor (Scheme 2).
The cartridge CatCard THS 01111 (10% Pd/C) was
used as catalyst to reduce the compounds 3a—d. Hydrogen
was generated by electrolysis of water. The process was
carried out at 60 °С, 20 bar, and 1 mL min–1 flow rate of
a isopropanol solution of an aromatic dinitrodiamine. The
reaction solution was passed through a column of activated
carbon at the end of the synthesis. The polynuclear tet-
raamines were obtained in a yield of 89—93% after distil-
3: R = H, X =
(a); R = H, X =
(b);
R = H, X =
(c);
R = CF3, X =
(d)
4 H, H (2´,2´,6´,6´)
2 H, H(3´´,3´´)
2 H, H(6´´,6´´)
4 H, 2 NH2
4 H, H (3´,3´,5´,5´)
4.04
4.04
2.00
3.98
8.3 8.2 8.1 8.0 7.9 7.8 7.7 7.6 7.5 7.4 7.3 7.2 7.1 7.0 6.9 6.8 6.7 6.6 δ, м.д.
18
17
16
15
14
13
12
11 10
9
8
7
6
5
4
3
2
1
0
δ, м.д.
Fig. 1. 1Н NMR spectrum of 2,2-bis[4-(5-amino-4-nitro-2-trifluoromethylphenoxy)pnenyl]hexafluoropropane (3d).

1074
Russ. Chem. Bull., Int. Ed., Vol. 67, No. 6, June, 2018
Begunov et al.
Table 1 Influence of the structure of electrophile 1 and nucleophile 2 on the time and yield of SNAr reaction
products
Entry
Electrophile
Nucleophile
τ/min
Product
Yield (%)
1
2
3
4
1a
1a
1a
1b
2a
2b
2c
2c
100
130
120
5
3a
3b
3c
3d
96
93
94
98
Reaction conditions: ultrasound, 80 °С, DMSO, K2СО3 (0.034 mol), 1 (0.028 mol), 2 (0.014 mol).
according to 1Н NMR spectroscopy, high-resolution mass
spectrometry, and elemental analysis. Figure 2 shows the
1Н NMR spectrum of compound 4d with eight protons of
four amino groups and four bands of twelve aromatic protons.
The signals of protons located in ortho-positions with respect
to the amino group are observed in the upfield region of the
spectrum at δ 6.29 and 6.85. The signal of four protons, which
are deshielded by an ortho-located hexafluoropropane sub-
stituent, are observed in the most downfield region at δ 7.29.
The efficiency of the proposed method for the fabrica-
tion of high-purity polynuclear tetraamines was confirmed
by the further synthesis of polyheteroarylenes. The origi-
nal approach was applied for the polyheterocyclization.
It consists of using supercritical carbon dioxide (sc-CO2)
as the reaction medium15,16 without the use of such haz-
ardous solvents as polyphosphoric acid, Eaton’s reagent,
and phenolic solvents.
Scheme 2
4: R = H, X =
(a); R = H, X =
(b);
R = H, X =
(c);
R = CF3, X =
(d)
lation of a portion of the solvent. The tetraamino com-
pound 4a—d did not contain impurities of other substances
Polynaphthoylenebenzimidazoles (P-1 and P-2) and
polyphenylquinoxalines (P-3 and P-4) (Scheme 3) were
2 H, H(3´´,3´´)
4 H, H(3´,3´,5´,5´)
2 H, H(6´´,6´´)
4 H, H(2´,2´,6´,6´)
4.00
1.98
3.96
2.02
7.3
7.2 7.1
7.0
6.9 6.8
6.7 6.6 6.5 6.4 6.3 δ, м.д.
4 H, (5-NH2)2
4 H, (4-NH2)2
3.96
4.00
1.98
3.91
3.98
2.02
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0 3.5
3.0
2.5
2.0
1.5
1.0
0.5 δ, м.д.
Fig. 2. 1Н NMR spectrum of 2,2-bis[4-(4,5-diamino-2- trifluoromethylphenoxy)pnehyl]hexafluoropropane (4d).

Polynuclear tetraamines
Russ. Chem. Bull., Int. Ed., Vol. 67, No. 6, June, 2018
1075
Scheme 3
P1, P3: X =
; P2, P4: X =
Conditions: i. PhCO2H, benzimidazole; ii. EtOH or PhCH2OH.
obtained on the basis of tetraamines 4a and 4c. Some of
their properties were investigated.
The process of the formation of polymers in sc-СО2
was carried out at 90 °С (for PNBI) and 50 °С (for PPQ)
at a pressure of 150 bar for 6 h using benzimidazole and
benzoic acid, ethyl or benzyl alcohols as catalysts, respec-
tively.
and NH2-groups of the tetraamine, respectively.21 The
intense bands in the region of 1600 and 1475 cm–1, at-
tributable to the stretching vibrations of the —C=C— and
—C=N— of aromatic heterocycles in PPQ were ob-
served.22 Thus, based on the analysis of IR spectroscopy
data it can be concluded that polyheteroarylenes were
obtained during the polyheterocyclization reaction.
According to the powder X-ray diffraction analysis, the
samples of PNBI and PPQ are amorphous due to the
possibility of the formation of geometric isomerism during
synthesis.23
Some characteristics of the obtained polymers are
presented in Table 2. The temperatures for the onset of
decomposition in air for the PNBI and PPQ synthesized
in sc-СО2 were about 470 °С and 500 °С. This was in good
agreement with the results for this type of polymers syn-
Characteristic absorption bands of the naphthoylene-
benzimidazole system are present in the IR spectra of the
P-1 and P-2 products at 1700 cm–1 (>C=O groups of the
pyridinone ring14) and in the range of 1630—1580 cm–1
corresponding to the valence C=N vibrations (1622 cm–1),
C=C vibrations (1608 cm–1), and C=C vibrations of nod
atoms (1595 cm–1).17,18 The stretching vibrations of the
benzimidazole polymer fragment also include absorption
peaks at 1487, 1448, and 1423 cm–1 19
brations of the Ar—O—Ar ether bonds corresponded to
the absorption band at 1228 cm–1 20
However, the peaks
.
The stretching vi-
.
in the region 3300—3500 cm–1 characteristic for the
stretching vibrations of amino groups,21 and also at 1706
and 1658 cm–1, corresponding to stretching vibrations of
C=O in the six-membered imide ring7 were not present
in the IR spectrum of the polymers. The obtained data
confirm that the monomers were fully consumed in the
polycondensation reaction. There were no absorption
bands in the IR spectra of the P-3 and P-4 products at
1680 and 3300—3500 cm–1, characteristic for the stretch-
ing vibrations of the C=O groups of the bis (α-diketone)5
Table 2. Yield and some characteristics of the obtained
polymers
Polymer
Yield
(%)
Тsoft
Тdec
ηred*
/dL g–1
°С
P1
P2
P3
P4
93
94
99
98
315
250
245
235
475
470
500
500
0.31
0.34
0.42
0.49
* Solution in NMP at 25 °С.

1076
Russ. Chem. Bull., Int. Ed., Vol. 67, No. 6, June, 2018
Begunov et al.
thesized by the classical method in solution.24,25 The
softening temperatures of polymers are in the range of
235—315 °С. Polymer PNBI, especially sample P-1, had
a softening temperature higher than the PPQ. This is ap-
parently due to the lower flexibility of the polymer chain
of PNBI, which includes a large number of fused frag-
ments.
2.7 Hz); 7.01 (d, 1 Н, Н(5), J = 2.3 Hz); 7.08 (d.d, 2 Н, H(4,6),
J = 2.3 Hz, J = 8.2 Hz); 7.48 (s, 4 Н, (NH2)2); 7.57 (t,
1 Н, Н (5), J = 8.2 Hz); 8.01 (d, 2 Н, Н(5´,5´), J = 9.5 Hz).
Found (%): С, 56.29; Н, 3.61; N, 14.86. C18H14N4O6. Calculated
(%): С, 56.54; Н, 3.66; N, 14.66.
1,4-Bis(3-amino-4-nitrophenoxy)benzene (3b). Yield 93%,
m.p. 280—282 °С. Found: m/z 383.0986 [M + H]+. C18H15N4O6.
1
Calculated: 383.0992. Н NMR (DMSO-d6), δ: 6.33 (d.d, 2 Н,
Obtained PNBI samples were soluble in N-methyl-
pyrrolidone (NMP), a mixture of phenol—tetrachloroeth-
ane, m-cresol, sulfuric acid. The samples of PPQ were
soluble in NMP, chloroform, phenol—tetrachloroethane,
benzyl alcohol, m-cresol, and sulfuric acid. Strong films
with a strain value at break of εr = 4.6%, a stress at break
of σr = 70 MPa, and a modulus of elasticity of
E = 3107 MPa were obtained from a 5% P-4 solution in
NMP by casting method.
Thus, we proposed an efficient method for the fabrica-
tion of high-purity polynuclear tetraamines. Two samples
of polyheteroarylene (PNBI and PPQ) were successfully
synthesized on their basis in sc-СО2 by modern and tech-
nological methods.
Н(6´,6´), J = 2.5 Hz, J = 9.0 Hz); 6.46 (d, 2 Н, Н(2´,2´), J =
2.0 Hz); 7.27 (d, 4 Н, Н(2,3,5,6), J = 8.0 Hz); 7.56 (s, 4 Н,
(NH2)2); 8.03 (d, 2 Н, Н(5´,5´), J = 9.0 Hz). Found (%): С, 56.39;
Н, 3.62; N, 14.81. C18H14N4O6. Calculated (%): С, 56.54; Н, 3.66;
N, 14.66.
2,2-Bis[4-(3-amino-4-nitrophenoxy)phenyl]hexafluoropro-
pane (3c). Yield 94%, m.p. 182—184 °С. Found: m/z 609.1201
[M + H]+. C27H18F6N4O6. Calculated: 609.1210. 1Н NMR
(DMSO-d6), δ: 6.35 (d.d, 2 Н, Н(6´,6´), J = 1.3 Hz, J =
= 8.2 Hz); 6.52 (d, 2 Н, Н(2´,2´), J = 1.5 Hz); 7.28 (d, 4 H,
H(3´,3´,5´,5´), J = 8.5 Hz); 7.45 (d, 4 H, H(2´,2´,6´,6´), J =
= 8.4 Hz); 7.53 (s, 4 H, (NH2)2); 8.05 (d, 2 Н, Н(5´,5´), J =
= 8.8 Hz). 19F NMR (DMSO-d6), δ: –63.33. Found (%):
C, 53.30; H, 2.93; N, 9.24. C27H18F6N2O6. Calculated (%):
C, 53.21; H, 2.96; N, 9.20.
2,2-Bis[4-(5-amino-4-nitro-2-trifluoromethylphenoxy)phe-
nyl]hexafluoropropane (3d). Yield 98%, m.p. 112—115 °С. Found:
m/z 745.0951 [M + H]+. C29H17F12N4O6. Calculated: 745.0957.
1H NMR (DMSO-d6), δ: 6.51 (s, 2 Н, Н(6´,6´)); 7.37 (d, 4 H,
Н(3´,3´,5´,5´), J = 8.5 Hz); 7.5 (d, 4 H, Н(2´,2´,6´,6´), J =
= 8.5 Hz); 7.90 (s, 4 H, (NH2)2); 8.32 (s, 2 Н, Н(3´,3´)).
19F NMR (DMSO-d6), δ: –57.56, –63.49. Found (%): C, 46.67;
H, 2.12; N, 7.56. C29H16F12N4O6. Calculated (%): C, 46.71;
H, 2.15; N, 7.52.
Experimental
1Н NMR spectra were registered using a Bruker DRX500
(500 MHz) spectrometer, solvent DMSO-d6, internal TMS
standard. High-resolution mass spectra were registered using a
Bruker micrOTOF II spectrometer, ESI ionization. Elemental
analysis was carried out using a Carlo Erba 110 (Italy) CHN
analyzer. IR spectra of the samples were registered using a Nexus
FTIR spectrometer (Thermo-Nicolet, USA) in the region of
4000—400 cm–1, in KBr pellets. Thermogravimetric analysis was
carried out using a Derivatograph-C (MОМ, Hungary) with
samples of ~15 mg at heating rate of 10 deg min–1 in air.
Thermomechanic investigations were carried out using a
UIP_70М device (Russia). Heating rate was 5.0 deg min–1 at
load of 0.2 MPA. The analysis of polymer film samples was car-
ried out using a LR5K Plus device (Lloyd Instrument) at defoma-
tion rate of 50 mm min–1 in air. Carbon dioxide corresponded
to the Russian standard 8050-85, and had a purity of 99.998%
(BKZ ltd., Balashikha, Russia). Volume fraction of water in СО2
was 5•10–6 vol.% according to technical data of the manufac-
turer.
Synthesis of polynuclear tetraamines 4a—d (general proce-
dure). The catridge containing 10% Pd/C catalyst was placed in
the H-Cube Pro reactor, and using the pump the flow rate of
solvent of 1 mL min–1 was adjusted. Isopropanol was pumped
through reactor for 5 min to remove the air from the system. The
substrate solution was prepared by the dissolution of dinitroarene
3a—d (1 g) in isopropanol (90 mL). The temperature of 60 °С
and pressure of 20 bar were set on the H-Cube device. When
stable conditions were established in the reactor, the inlet system
was switched from the solvent to the substrate and the substance
was passed through the catalyst. After collecting the entire solu-
tion, the inlet valve was switched back to the solvent and the
system was rinsed for 10 min. The reaction solution was passed
through a column of activated carbon, then most of the solvent was
evaporated. After cooling, the formed precipitate was filtered off.
1,3-Bis(3,4-diaminophenoxy)benzene (4а). Yield 91%, m.p.
169—171 °С. Found: m/z 323.1506 [M + H]+. C18H19N4O2.
Calculated: 323.1509. 1H NMR (DMSO-d6), δ: 4.49 (s, 8 H,
(3,4-NH2)4); 6.09 (d.d, 2 H, H(6´,6´), J = 1.8 Hz, J =
= 8.6 Hz); 6.24 (d, 2 H, H(2´,2´), J = 1.6 Hz); 6.36 (t, 1 H,
H(2), J = 7.3 Hz); 6.44 (d.d, 2 H, H(4,6), J = 1.7 Hz, J =
= 8.8 Hz); 6.49 (d, 2 H, H(5´,5´), J = 9.1 Hz); 7.15 (t, 1 H, H(5),
J = 9.2 Hz). Found (%): C, 66.89; H, 5.52; N, 17.36. C18H18N4O2.
Calculated (%): C, 67.10; H, 5.57; N, 17.34.
Sonication was carried out in a S10H bath (Elma Schmidbauer
GmbH, Germany) with ultrasound frequency of 37 kHz at 80 °С.
The reduction of dinitroarenes was carried out in a H-CUBE
Pro reactor for flow hydrogenation (ThalesNano Nanotechnology
Inc, Hungary).
Synthesis of diaminodinitroarenes 3a—d (general procedure).
Reaction mixture of K2СО3 (0.034 mol), compound 1 (0.028
mol), and compound 2 (0.014 mol) in DMSO (40 mL) was
sonicated at 80 °С for 5 min to yield compound 3d, for 100 min
to yield 3a, for 120 min to yield 3c, and for 130 min to yield 3b.
After cooling down the reaction mixture was poured into water,
precipitate was filtered and dried.
1,4-Bis(3,4-diaminophenoxy)benzene (4b). Yield 93%, m.p.
224—227 °С. Found: m/z 323.1508 [M + H]+. C18H19N4O2.
Calculated: 323.1509. 1H NMR (DMSO-d6), δ: 4.42—4.51 (s,
8 H, (NH2)4); 6.08 (d.d, 2 H, H(6´,6´), J = 1.8 Hz, J = 8.6 Hz);
6.26 (d, 2 H, H(2´,2´), J = 1.6 Hz); 6.49 (d, 2 H, H(5´,5´), J =
=9.1 Hz); 6.83 (4 H, H(2,3,5,6)). Found (%): C, 66.95; H, 5.51;
1,3-Bis(3-amino-4-nitrophenoxy)benzene (3а). Yield 96%,
m.p. 195—197 °С. Found: m/z 383.0984 [M + H]+. C18H15N4O6.
1
Calculated: 383.0992. Н NMR (DMSO-d6), δ: 6.33 (d.d, 2 Н,
Н(6´,6´), J = 2.7 Hz, J = 9.5 Hz); 6.45 (d, 2 Н, Н(2´,2´), J =

Polynuclear tetraamines
Russ. Chem. Bull., Int. Ed., Vol. 67, No. 6, June, 2018
1077
N, 17.38. C18H18N4O2. Calculated (%): C, 67.10; H, 5.57;
N, 17.34.
2. P. M. Hergenrother, in Encyclopedia of Polymer Science and
Engineering, Vol. 13, Eds H. F. Mark, N. M. Bikales, C. G.
Overberger, G. Menges, J. I. Kroschwitz, Wiley, New York,
1988, p. 55.
3. G. Rabilloud, High Performance Polymers. 2. Polyquinoxalines
and Polyimides: Chemistry and Applications, Editions Technip,
Paris, 1999, 350 pp.
4. P. M. Lindley, B. A. Reinhardt, J. Polym. Sci., Part A: Polym.
Chem., 1991, 29, 1061.
5. H. J. Ni, J. G. Liu, S. Y. Yang, Chem. Lett., 2016, 45, 75.
6. N. Li, S. Zhang, J. Liu, F. Zhang, Macromolecules, 2008, 41,
4165.
2,2-Bis[4-(3,4-diaminophenoxy)phenyl]hexafluoropropane
(4c). Yield 91%, m.p. 154—157 °С. Found: m/z 549.1713 [M + H]+.
C27H23F6N4O2. Calculated: 549.1726. 1H NMR (DMSO-d6), δ:
4.37 (s, 4 H, (4-NH2)2); 4.66 (s, 4 H, (3-NH2)2); 6.14 (d.d, 2 H,
H(6´,6´), J = 1.6 Hz, J = 8.5 Hz); 6.28 (d, 2 Н, Н(2´,2´), J =
= 1.5 Hz); 6.51 (d, 2 Н, Н(5´,5´), J = 8.8 Hz); 6.92 (d, 4 H,
H(3´,3´,5´,5´), J = 8.5 Hz); 7.24 (d, 4 H, H(2´,2´,6´,6´),
J = 8.4 Hz). 19F NMR (DMSO-d6), δ: –63.49. Found (%):
C, 58.94; H, 3.98; N, 10.23. C27H22F6N4O2. Calculated (%):
C, 59.01; H, 4.01; N, 10.20.
2,2-Bis[4-(4,5-diamino-2- trifluoromethylphenoxy)phenyl]
hexafluoropropane (4d). Yield 89%, m.p. 232—235 °С. Found:
m/z 685.1463 [M + H]+. C29H20F13N4O2. Calculated: 685.1474.
1H NMR (DMSO-d6), δ: 4.76 (s, 4 H, (4-NH2)2); 5.27 (s, 4 H,
(5-NH2)2); 6.29 (s, 2 Н, Н(6´,6´)); 6.85 (s, 2 Н, Н(3´,3´)); 6.95
(d, 4 H, Н(3´,3´,5´,5´), J = 8.5 Hz); 7.29 (d, 4 H, Н(2´,2´,6´,6´),
J = 8.5 Hz). 19F NMR (DMSO-d6), δ: –57.53, –63.46. Found (%):
C, 50.76; H, 2.89; N, 8.20. C29H20F12N4O2. Calculated (%):
C, 50.80; H, 2.92; N, 8.18.
Synthesis of polynaphthoylenebenzimidazoles P1, P2 (general
procedure). A carefully stirred mixture of dianhydride of
1,3-bis(4,5-dicarboxynaphthalen-1-ylcarbonyl)benzene (5),
tetradiamine 4a or 4d, a mixture of benzimidazole and benzoic
acid, taken each 1 mmol, was loaded into high-pressure reactor
with volume of 22 mL. The reactor was purged with carbon di-
oxide to remove water vapors before the synthesis. Then it was
heated to a temperature of 90 °С in a thermostat with a program-
mable temperature controller. Stirring in the reactor was carried
out with a magnetic stirrer. The carbon dioxide was fed into the
reactor and the necessary pressure of 150 bar was created by
means of a piston generator (High Pressure Equipment Company,
USA). After the required conditions were created, the reactor
was held for 6 h. At the end of the reaction and cooling of the
system, stirring was switched off and the system was decom-
pressed. The resulting polymer was dissolved in NMP, then
precipitated with water, filtered, washed with ethanol, and dried
under vacuum for 10 h at 100 °С.
7. H. Mao, S. Zhang, Polymer, 2014, 55, 102.
8. N. M. Belomoina, A. L. Rusanov, M. Bruma, Polym. Sci.,
Ser. C (Engl. Transl.), 2007, 49, 1426.
9. M. L. Keshtov, A. L. Rusanov, V. V. Kireev, A.A Kirillov,
S. V. Keshtova, F. W. Harris, Polym. Sci., Ser. B (Engl. Transl.),
2001, 43, 737.
10. E. P. Fokin, I. G. Sivakova, K. I. Matoshina, Izv. Sib. Otd.
Akad. Nauk SSSR, Ser. Khim. Nauk (Engl. Transl.), 1969,
3, 92.
11. R. W. Thies, G. R. Collins, T. Sekin, C. K. Welborne, C. B.
Svendsen, A. A. Ross, S. D. Grimes, Macromolecules, 1992,
25, 1207.
12. А. N. Valyaeva, PhD Thesis, P. G. Demidov Yaroslavl State
University, Yaroslavl, 2013, 142 pp.
13. R. S. Begunov, A. N. Valyaeva, V. V. Belyaev, N. O.
Dobretsova, Russ. Chem. Bull., 2015, 64, 1971.
14. J. Wang, N. Li, F. Zhang, S. Zhang, J. Liu, Polymer, 2009,
50, 810.
15. E. Kiran, J. Supercrit. Fluids, 2016, 110, 126.
16. N. M. Belomoina, E. G. Bulycheva, L. N. Nikitin, V. G.
Vasilyev, I. V. Elmanovich, M. Bruma, J. Supercrit. Fluids,
2016, 113, 66.
17. H. Zhang, X. Li, C. Zhao, T. Fu, Y. Shi, H. Na, J. Membr.
Sci., 2008, 308, 66.
18. S. Kohama, J. Gong, K. Kimura, S. Yamazaki, T. Uchida,
K. Shimamura, K. Kimura, Polymer, 2008, 49, 1783.
19. W. Huang, S. Qing, J. Yang, D. Yan, Chin. J. Polym. Sci.,
2008, 26, 121.
20. А. Kh. Kuptsov, G. N. Zhizhin, Fur’e KR- i Fur’e IK-spektry
polimerov [Fourier Raman and IR spectra of polymers],
Fizmatlit, Moscow, 2001, 656 pp.
Synthesis of polyphenylquinoxalines P3, P4 (general proce-
dure). A thoroughly mixed mixture of 1,4-bis(phenylglyoxalyl)-
benzene (6), tetraamine 4a or 4d, taken 1 mmol each, and ethyl
or benzyl alcohol (1 mL) was charged into a 22 mL high-pressure
stainless steel reactor. The reactor was purged with carbon diox-
ide to remove water vapor before synthesis, and then heated to
50 °С. After conditioning, the reactor was held for 6 h at this
temperature. Formed polyphenylquinoxaline was then treated as
described above.
21. Infrared Absorption Spectroscopy, Ed. K. Nakanishi, Holden-
Day, San Francisco, 1962, 233 pр.
22. F. Gong, N. Li, S. Zhang, Polymer, 2009, 50, 6001.
23. W. Y. Wrasidlo, Polymer Preprints, 1971, 12, 755.
24. V. V. Korshak, A. L. Rusanov, A. M. Berlin, S. Kh. Fidler,
F. I. Adyrkhaeva, Polym. Sci., Ser. А (Engl. Transl.), 1979,
21, 68.
The work was financially supported by the Russian
Foundation for Basic Research (Project No 16-03-00119
and 16-53-52032 MNT_a) and the Ministry of Science
and Technology (Taiwan, R.O.C.) (Project MOST
105–2923-E–006–003-MY3).
25. E. S. Kronhaus, Polym. Sci., Ser. А (Engl. Transl.), 1984, 26, 227.
References
1. B. Sillion, Comprehensive Polymer Science, Vol. 5, Eds G. C.
Eastmond, A. Ledwith, S. Russo, P. Sigwalt, Pergamon Press,
Oxford, 1989, 499 pp.
Received January 22, 2018;
in revised form February 27, 2018;
accepted April 12, 2018