Production of macrocyclic polyether benzo-15-crown-5 and its functional derivatives

Article abstract of DOI:10.13005/ojc/330413

Study of interaction between catechol and tetraethylene glycol dichloride in the n-butanol media, resulting with benzo-15-crown-5 production. Production of nitro- and amino-derivatives of benzo-15-crown-5. Determination of their thermogravimetric characteristics.

Full text of DOI:10.13005/ojc/330413

ISSN: 0970-020 X
CODEN: OJCHEG
2017, Vol. 33, No. (4):
Pg.1689-1697
ORIENTAL JOURNAL OF CHEMISTRY
An International Open Free Access, Peer Reviewed Research Journal
www.orientjchem.org
Production of Macrocyclic Polyether Benzo-15-Crown-5
and its Functional Derivatives
VALENTINA N. GLUSHkO*, NATALYAYU. SADOVSkAYA, VADIM I. kOzHUHOV,
LIDIYA I. BLOkHINA, IRINA A. ANTROPOVA, EkATERINA S. PETINA,
VASILIY M. RETIVIOV and EkATERINAYU. MELNIkOVA
The Federal State Unitary Enterprise «Institute of Chemical Reagents and High Purity Chemical
Substances of National Research Centre «Kurchatov Institute», Bogorodsky val str.3, Moscow.
*Corresponding author e-mail; tetrazoli@yandex.ru
http://dx.doi.org/10.13005/ojc/330413
(Received: April 06, 2017; Accepted: June 06, 2017)
ABSTRACT
Study of interaction between catechol and tetraethylene glycol dichloride in the n-butanol
media, resulting with benzo-15-crown-5 production. Production of nitro- and amino-derivatives of
benzo-15-crown-5. Determination of their thermogravimetric characteristics.
keywords: benzo-15-crown-5, catechol, tetraethylene glycol dichloride, crown ether,
gas liquid chromatography, chromate-mass spectrometry
INTRODUCTION
already helped crown ethers secure their place in
medicine7, botany8, engineering and technology9.
The results of studying crown ethers, which
were discovered in 1962, allowed to reveal their
properties ensuring their successful use for solving
issues in various fields of science, medical practice
and modern manufacturing. A unique property of
crown ethers is their high selectivity in terms of
forming host-guest complexes formation with metal
ions and neutral organic molecules.Such interaction
is specific and determined by both electronic and
topological factors, which opens broad prospects
for using crown ethers as highly selective splitters,
carriers, catalyst and the like1-6.These properties has
It is possible to synthesize crown-ether-
based adsorbing agents, and their adsorbing ability
could be further improved due to the crown-ether
fragments chemically attached to them.Non-soluble
polymers with crown units in their backbone or side
chains turn out to be preferable over their monomer
analogues, since they are easier to process,
regenerate and reuse.
For example, adding of ether groups to
chloromethylated styrene/divinylbenzene copolymer

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GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
enabled the prodution of electrodialysis membranes with its duration and pressure of 1.75 h and 1551.49
capable of alkali metal chlorides adsorbing and torr respectively.
releasing them after slight temperature increase.
Feigenbaum and Michel20 produced cis-
Amino- and diamino-crown ethers and and trans-isomers of diaminodibenzo-18-crown-6
nitrogen-containing heterocyclic compounds suitable by hydrogenating corresponding individual dinitro-
for further functional improvement. are of particular isomers in the form of suspension over Raney nickel
interest, since their compounds which are suitable in dimethylformamide, using pressurized hydrogen.
can immobilize into various organic and non-organic Figure 1 shows 4-aminobenzo-15-crown-5 synthesis
carriers and act as an initial material for forming new scheme.
nitrogen-containing structures formation.
MATERIALS AND METHODS
Amino-substituted crown compounds can
also undergo acylation, phosphorylation, addition,
A series of experiments was conducted
condensation, alkylation and arylation reactions, as to determine the optimal conditions for performing
well as form isocyanates under phosgene effect and benzo-15-crown-5 production reactions.
can be immobilized on carrier surface3.
For the purpose of ensuring of selective
Despitegrowinginterestinthesecompounds behavior of cyclization reaction, which results in
over recent years, the current number of papers cyclic compounds, and inhibiting side reactions that
on the synthesis of macrocyclic polyethers is lead to formation of linear polymers, a high dilution
extremely small10-15.For example, benzo-15-crown-5 method is used for synthesizing crown ethers,
can be produced using Williamson synthesis since the formation of macrocyclic product through
reaction, featured by interaction between catechol intramolecular reaction in diluted solutions is more
(orto-dihydroxybenzene) and tetraethylene glycol likely, thus process will be faster than polymer
dichloride (1,10-dichloro-3,6,9-trioxadecane) over formation, which requires collisions between two
sodium hydroxide in the n-butanol media (30-h inert- reagents (intermolecular reaction)21-22
atmosphere boiling).The yield of benzo-15-crown-5
.
produced by this method is 62%, with the basic
substance’s mass fraction of 95%.
Since sodium hydroxide is used as a
template agent in production process, the method
of adding tetraethylene glycol dichloride (TEGDC)
Nitro-derivative B15C6 is produced by addition plays an important role, due to its possible
also applying 76% HNO3 in a glacial acetic acid. hydrolysis in the alkali media. Therefore, three
This method was used for producing 4'-nitro- methods of this reagent addition to the reaction
B18C6, 4'- nitro-B15C5 and 4',5'-dinitro-B15C5 and (dropwise addition;adding 1/3 of tetraethylene glycol
nitro-derivatives B18C6 respectively16. Mononitro- dichloride amount every ten minutes;and adding the
derivatives B18C6 and B15C5 too were also whole amount of tetraethylene glycol dichloride at
synthesized using 58% HNO3 in acetonitrile17.
once) were studied. A thermodynamic condition of
the reaction mixture during dichloride addition varied
The relevant literature contains only a few too.
main methods of producing amino-derivatives of
benzo- and dibenzo-crown ethers production.In one
The following reagents were using for
of their latest papers18 the authors reduced dinitro- synthesizing benzo-15-crown-5: catechol, 99.6%
derivatives of crown ethers by hydrazine hydrate over (manufacturer:Merck);tetraethylene glycol dichloride,
palladium on carbon in the diethylene glycol dimethyl 98.5%; n-butanol, 99.5%; sodium hydroxide, 99.5%;
ether media.
hydrochloric acid, 38%; and pure-grade hexane.
In case of paper19, the reduction was carried
Benzo-15-crown-5 synthesis (Synthesis
out over palladium on carbon in dimethylformamide, 1: dropwise addition of tetraethylene glycol
dichloride).

GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
1691
General procedure
88 g (0.8 mole) catechol and 1200 ml
1H Nuclear magnetic resonance
(DMSO-d6, 300 MHz): 3.62 (broad singlet, 8H,
CH2+CH2+CH2+CH2), 3.73-3.81 (multiplet, 4H,
CH2+CH2), 4.00-4.09 (multiplet, 4H, CH2+CH2),
6.85-6.99 (multiplet, 4H, aromatic CH).
n-butanol was plased into a 2-liter flask equipped
with a mechanical stirrer, thermometer, water
condenser and dropping funnel was placed. After
dissolution of the catechol by stirring, aqueous NaOH
solution (67.2 g NaOH to 80 ml H2O) was added.
Mixing duration was 30 to 40 minutes.After 156.6 ml
(0.8 mole) tetraethyleneglycol dichloride was
dripped through dropping funnel at 17 ml/min rate.
The mixture was refluxed for 7 hours (107 0C). After
that, the filtrate was acidified with concentrated
hydrochloric acid, filtered off and flushed with water
until neutral reaction was reached. Upper organic
layer was put into round-bottom flask, treated with
activated carbon and filtered off.Then the filtrate was
boiled out using rotary evaporator, accompanied
by complete solvent distillation. The residue was
extracted with hexane, followed by producing white
transparent crystals of benzo-15-crown-5.
13C Nuclear magnetic resonance (DMSO-
d6, 75 MHz): 68.42, 68.87, 69.79, 70.42, 113.92,
121.04, 148.63.
Benzo-15-crown-5 synthesis (Synthesis 2:
(adding tetraethyleneglycol dichloride in three equal
parts).
The process is similar to Synthesis 1
(dropwise addition). The only difference is that
tetraethyleneglycol dichloride was added to the
reaction mixture by 52.2 ml each 10 minutes.
Benzo-15-crown-5 synthesis (Synthesis
3: adding the whole amount of tetraethylenglycol
dichloride).
Infrared spectrum (KBr, ν, cm-1): 468
(weak), 514 (weak), 538 (weak), 602 (weak), 740
(strong) (aromatic C-H), 779 (weak), 851 (medium),
906 (weak), 938 (strong) (aromatic C-H), 980 (weak),
1042 (medium), 1051 (strong), 1076 (medium), 1094
(medium), 1121 (strong) (C-O-C), 1130 (strong)
(C-O-C), 1226 (strong) (aromatic C-H), 1261 (strong)
(aromatic C-H), 1269 (medium), 1335 (medium),
1345 (medium), 1362 (weak), 1412 (weak), 1455
(medium), 1509 (strong) (CH2), 1593 (medium), 2863
(strong) (C-H), 2920 (strong) (C-H), 2940 (strong)
(C-H), 3009 (weak) (C-H aromatic), 3036 (weak)
(C-H aromatic), 3060 (weak) (C-H aromatic)
The process is similar to Synthesis 1. The
only difference is that 156.6 ml tetraethyleneglycol
dichloride was added to the reaction mixture at
once.
Benzo-15-crown-5 synthesis (Synthesis 4:
dropwise addition of tetraethyleneglycol dichloride
to boiling reaction mixture).
The process is similar to Synthesis 1. The
only difference is that reaction mixture was heated
to the boiling point prior to dichloride addition.
Fig.1: 4-aminobenzo-15-crown-5 synthesis scheme

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GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
Benzo-15-crown-5 synthesis (Synthesis acid (which is poor nitration agent and quite strong
5: adding tetraethyleneglycol dichloride to boiling oxidizing agent) is also used due to the constant
reaction mixture in three equal parts).
presence of nitrous acid that hinders nitration.
Another drawback of diluted nitric acid, which limits
The process is similar to Synthesis 2. The its use, is its ability to express nitrating effect only at
only difference is that reaction mixture was heated high temperatures, which are featured by prevailing
to the boiling point prior to dichloride addition.
side oxidation reaction. Concentrated nitric acid
shows nitrating effect at lower temperatures and less
Benzo-15-crown-5 synthesis (Synthesis likely to cause undesirable oxidation, which is why we
3: adding the whole amount of tetraethyleneglycol carried out a nitration of resulted benzo-15-crown-5
dichloride to boiling reaction mixture).
with nitric acid, 56%, in the acetonitrile media. The
yield of target product was 99.5%, while the melting
The process is similar to Synthesis 2. The point of resulted compound was 94-95 0C.
only difference is that 156.6 ml tetraethyleneglycol
dichloride was added to the reaction mixture, which,
in turn, was preheated to the boiling point.
Infrared spectrum (KBr, ν, cm-1): 497
(weak), 538 (weak), 618 (weak), 654 (medium)
(aromatic C-H), 723 (weak), 745 (medium) (NO2),
Reaction flow monitoring was carried out 787 (weak), 806 (medium), 868 (medium) (N-O), 913
using GlC method. Molar concentration values (weak), 934 (medium), 980 (medium), 1010(weak),
of target product within reaction mixture were 1047 (medium), 1093 (strong) (C-N), 1138 (strong)
determined using gas liquid chromatography (C-O-C), 1240 (strong) (NO2), 1276 (strong) (NO2),
(Table 1):
1335 (strong) (NO2), 1417 (strong), 1428 (strong),
1448 (medium) (N=O), 1517 (strong) (CH2 + NO2),
For the purpose of studying of the kinetics 1587 (medium) (aromatic C-C), 2868 (medium)
of benzo-15-crown-5 production process, reaction (C-H), 2904 (medium) (C-H), 2929 (medium) (C-H),
mass sampling was carried out at fixed time intervals, 3083 (medium) (aromatic C-H).
using alcohol solution of hydrochloric acid as a stop
reagent (pH=3-4).
1HNuclear magnetic resonance
(DMSO-d6, 300 MHz): 3.62 (broad singlet, 8H,
Quantitative sample analysis was CH2+CH2+CH2+CH2), 3.74-3.85 (multiplet, 4H,
carried out using gas liquid chromatography CH2+CH2), 4.13-4.24 (multiplet, 4H, CH2+CH2), 7.15
(GlC), which, in turn, was performed using gas (doublet, 1H, J=8.9, CH), 7.73 (doublet, 1H, J=2.7,
chromatograph«Chromatec Crystal 5000.2», CH), 7.89 (double doublet, 1H, J=8.9, J=2.7, CH).
equipped with flame ionization detector and 30-m
long fused silica column BP-5, with its inner diameter
13C Nuclear magnetic resonance (DMSO-d6,
and fixed-phase film thickness of 0.32 mm and 75 MHz): 67.77, 68.84, 69.27, 69.71, 70.09, 70.16,
0.5 µm respectively. Carrier has: helium (rate: 2.8 70.30, 100.96, 105.53, 117.49, 139.35, 143.95,
ml/min, split ratio: 1:25, column temperature range: 149.92.
150-3000C, temperature setting: 100C/min.
Concentration values of sample components were 4-Aminobenzo-15-crown-5(AB15C5) production
calculated using percentage normalization per
area.
For the purpose of 4-nitrobenzo-15-crown-5
reducition we chose the method of reduction by
hydrazine hydrate over skeleton Raney nickel catalyst
in the alcohol media as the most convenient and
4-Nitrobenzo-15-crown-5 production (NB15C5)
Benzo-15-crown-5 nitration was carried out effective one.Contrary to other methods, a reduction
by nitric acid, 58%, over boiling reaction mass in the by hydrazine hydrate over nickel catalyst takes place
acetonitrile media, using relevant method17.
at normal pressure and without autoclave.
Nitric acid of various concentrations can be
5 g Raney nickel was added to 34 g (0.108
used in nitration reaction.In some cases, diluted nitric mole) 4-nitrobenzo-15-crown-5 with in 200-ml ethyl

GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
1693
alcohol and heated to 500 0C, followed by dripping
34 ml hydrazine hydrate. In one hour’s time it was
filtered off the catalyst, with solution boiled out and
residue recrystallized from 30-ml ethyl alcohol. The
yield of AB15C5 was 70%, with its melting point of
79.5-80.5 0C.
Reaction products were identified using
chromate-mass spectrometry
It was found out that there were two
impurities, identified as compounds A and B, which
formed alongside with benzo-15-crown-5.The
formation of impurity A was the result of tetraethylene
glycol dichloride hydrolysis, while impurity B was
2-(2-(2-(2-(2-chlorethoxy)ethoxy)ethoxy)ethoxy)
phenol. Structural formulas of these side products
are shown in Figures 2 and 3 below.
Infrared spectrum (KBr, ν, cm-1): 497
(weak), 581 (weak), 631 (weak), 712 (weak), 766
(weak), 793 (weak) (NH2), 847 (medium) (NH2),
917 (weak), 940 (medium), 987 (medium), 1060
(medium) (C-O-C), 1079 (medium), 1127 (strong)
(C-O-C), 1181 (medium), 1217 (medium) (C-N),
1251 (medium), 1294 (medium), 1332 (weak),
1355 (weak), 1452 (medium), 1511 (strong) (CH2),
1589 (weak) (aromatic C-C), 1610 (medium) (NH2),
2878 (medium) (C-H), 2921 (medium) (C-H), 2957
(medium) (C-H), 3056 (aromatic C-H), 3346 (strong)
(NH2), 3396 (strong) (NH2).
In case of Synthesis 1, apart from
target product (i.e. benzo-15-crown-5 (80.09%)),
intermediate and side products, the reaction mixture
also contained initial catechol and tetraethylene
glycol dichloride (4.149% and 8.106% respectively)
at 6.5 h, time after the reaction had started. As
synthesis duration increased to 8.5 h, the content
of target product reached 82.097%, with its further
formation taking place at extremely low rate.
1HNuclear@ magnetic resonance
(DMSO-d6, 300 MHz): 3.60 (broad singlet, 8H,
CH2+CH2+CH2+CH2), 3.68-3.77 (multiplet, 4H,
CH2+CH2), 3.85-3.97 (multiplet, 4H, CH2+CH2), 4.67
(broad singlet, 2H, NH2), 6.05 (double doublet, 1H,
J=8.4, J=2.5, CH), 6.22 (doublet, 1H, J=2.5, CH),
6.63 (doublet, 1H, J=8.4, CH).
In case of tetraethylene glycol dichloride
addition in three equal parts every 10 minutes, the
concentration of target product under the same
conditions was 80.192%.In case of adding the whole
amount of tetraethylene glycol dichloride at once, the
concentration of target product was 78.431%.
13C Nuclear magnetic resonance (DMSO-
d6, 75 MHz): 67.77, 68.84, 69.27, 69.71, 70.09,
70.16, 70.30, 100.96, 105.53, 117.49, 139.35,
143.95, 149.92.
The curve of dependence between reaction
mixture and synthesis duration 1 is shown in
Figure 4.
Thus, benzo-15-crown-5 forms only
RESULTS AND DISCUSSION
after reaction mixture has been heated to its
boiling point (107 C), which takes 1.3 h. Then,
0
Reaction products were identified using gas
chromatograph«ChromatecCrystal500.2»,equipped
with mass spectrometry detector ThermoISQ and
15 m long fused silica column TR-5MS, with its
inner diameter and fixed-phase film thickness of
0.25 mm and 0.25µm respectively. Carrier has:
helium (rate: 2.8 ml/min, split ratio: 1:25, column
temperature range:150-280 0C, temperature setting:
20 0C/min. Mass spectrums of an electronic
impact were determined at the 70-eV energy of
the temperature of reaction mixture decreases to
102 0C, followed by formation of two side products,
A and B, in comparatively small quantities (4.211%
and 3.554% respectively).
Benzo-15-crown-5 is extracted from boiling
reaction mass by hexane. The mass fraction of
Fig. 2: 1-chlorine-11-hydroxy-
tetraethyleneglycol, m/z 212.5
0
ionizing electrons and 280 C temperature of ion
source. Reaction products were identified mainly
by comparing registered spectrum with that of
NISTUSA (2008) and also by molecular ion based
on the correlation between mass, spectrum and
structure.
Fig. 3: 2-(2-(2-(2-(2-chlorethoxy)ethoxy)ethoxy)
ethoxy)phenol, m/z 304.11

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GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
resulted product’s basic substance was 98%, with are adding tetraethyleneglycol dichloride to unboiled
its melting point of 79.5-80.5 0C.
reaction mass.
Given the kinetics of Sythesis 1, we
The chosen methods for the preparation
assumed that TEGDC addition to boiling reaction of nitro- and amino-derivatives of benzo-15-crown-5
mixture should accelerate the formation of crown make it possible to obtain the above-mentioned
ether and increase its yield.However, this assumption functional crown ethers with high yields and high
proved to be wrong, since dropwise addition of quality.
tetraethyleneglycol dichloride to boiling reaction
mixture resulted in target product’s concentration
Differential thermal analysis was used for
after 7 h boiling of 72.902%, which was 9.195% determining melting points and analyzing thermal
lower than that of similar synthesis with TEGDC decomposition process of B15C5, NB15C5 and
addition not accompanied by boiling. In case of AB15C5. TGA (thermo-gravimetric analysis) and
adding TEGDC in three parts, the concentration of DSC (differential scanning calorimetry) methods,
target product was 65.482%. In case of adding the as well as combined simultaneous thermal analyzer
whole amount of TEGDC at once, the concentration STD Q600 (manufacturer: TA Instruments (USA))
of target product was 58.934%.
were used in these study. Measurements were
carried out in air (flow rate: 100 ml/min.) inside
Thus, the best conditions for benzo-15- alundum crucibles, with the heating rate of 10 0C/min.
crown-5 synthesis among the above-mentioned ones and the temperature ranging from room temperature
to 300 0C.
Fig. 4: Dependence between reaction mixture composition and duration of Synthesis 1
Table 1 Target product percentage of the reaction mixture depending on reaction conditions
Method of adding
tetraethylene glycol
dichloride (TEGDC)
to reaction mass
B15C5 content of reaction mass, %
TEGDC addition to
TEGDC addition at
room temperature
boiling reaction mass
Dropwise TEGDC
1/3 of TEGDC amount every ten minutes
Full amount of TEGDC at once
82.097
80.192
78.431
72.902
65.482
58.934

GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
1695
Fig. 5: B15C5 thermograph
Fig. 6: NB15C5 thermograph
Fig. 7: AB15C5 thermograph

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GlUSHKO et al., Orient. J. Chem., Vol. 33(4), 1689-1697 (2017)
Thermal decomposition of crown-ethers DSC (differential scanning calorimetry) methods, as
is a complicated and staged process which well as combined simultaneous thermal analyzer
comprises 2 stages:compound melting, which takes STD Q600 (manufacturer: TA Instruments (USA))
0
place at temperatures of up to 100 C, compound were used in the study. Measurements were carried
decomposition, which begins within temperature out in air (flow rate: 100 ml/min.) inside alundum
0
range of 150-175 0C.
crucibles, with the heating rate of 10 C/ min. and
the temperature ranging from room temperature to
Figure 5 shows the thermograph of sample. 300 0C.
AnendothermicpeakatatemperatureB15C5ofabout
0
80 C, not accompanied by massive changes,
As it was shown, the melting point of B15C5
0
means the melting process. Decomposition begins was 80.48 C. Sample mass is reduced by 0.04 %
at 150 0C, with 14% mass loss at the first stage. At in the course melting process. In case of NB15C5,
217 C decomposition process accelerates and melting point and mass loss were 97.24 C and
lasts until the whole mass is lost. There is a narrow 0.44 % respectively.In case of AB15C5, melting point
exothermic peak at 274 0C, which point to possible and mass loss were 79.51 0C and 0.53%.
ignition of the substance.
0
0
CONCLUSION
Figure 6 shows the thermograph of sample.
An endothermic peak at a temperature NB15C5 of
Thestudyhasshownthattetraethyleneglycol
about 97 0C , not accompanied by massive changes, dichloride addition to the reaction mixture at the rate
means the melting process. An exothermic peak at of 17 ml/min. results in benzo-15-crown-5 content
0
a temperature of about 314 C, accompanied by reaching 82.097% of reaction mass. At the same
complete loss of mass, points to sample combustion time, we that 7 hours were proved as an optimal
during decomposition process.
dwell time at the boiling point, which allows to reduce
the reaction duration by 23 hours, comparing with
Figure 7 shows the thermograph of sample. the conventional method. It has also been found
An endothermic peak at a temperature AB15C5 that it is possible to carry out the reduction of
0
of about 97 C, accompanied by 0.5% massive nitrobenzo-15-crown-5 by using hydrazine hydrate
loss, points to a water loss process taking place over Raney nickel at normal atmospheric pressure.
alongside melting.The decomposition of this sample Thermogravimetric properties of resulted products
is complicated and comprises two stages.At the first have been determined.
stage, there is a rapid mass loss of 58% within the
temperature range of 170-297 0C.Then the process
slows down, with 77.7-% loss of sample mass at the
temperature of 400 0C.
ACkNOWLEDGMENTS
The applied researches are carried out with
state financial support represented by the Ministry of
Differential thermal analysis was used Education of Russia under the Agreement on granting
for determination of melting points and analysis of subsidies N0 (number)14.625.21.0034 of October
thermaldecomposition process of B15C5, NB15C5 27, 2015. (Unique identifier of Applied Scientific
and AB15C5.TGA (thermo-gravimetric analysis) and Researche (project) RFMEFI62515X0034).
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