Synthesis and complexing ability of N-[2-(2-morpholinoacetyl) hydrazinocarbothioyl]benzamide

Article abstract of DOI:10.1134/S1070363212110138

The synthesis and identification of N-[2-(2-morpholinoacetyl) hydrazinocarbothioyl]benzamide were performed. A qualitative and quantitative evaluation of its complexing ability to the Ni(II) and Co(II) ions was done. The stability constants of the Ni- and

Full text of DOI:10.1134/S1070363212110138

ISSN 1070-3632, Russian Journal of General Chemistry, 2012, Vol. 82, No. 11, pp. 1815–1818. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © Sh.K. Amerkhanova, O.A. Nurkenov, S.D. Fazylov, R.M. Shlyapov, A.S. Uali, Zh.B. Satpaeva, 2012, published in Zhurnal Obshchei
Khimii, 2012, Vol. 82, No. 11, pp. 1825–1828.
Synthesis and Complexing Ability
of N-[2-(2-Morpholinoacetyl)hydrazinocarbothioyl]benzamide
a
b
b
Sh. K. Amerkhanova , O. A. Nurkenov , S. D. Fazylov ,
a
a
b
R. M. Shlyapov , A. S. Uali , and Zh. B. Satpaeva
a
Buketov Karaganda State University , ul. Universitetskaya 28, Karaganda, 100028 Kazakhstan
e-mail: amerkhanova_sh@mail.ru
b
Institute of Organic Synthesis and Coal Chemistry of the Republic of Kazakhstan, Karaganda, Kazakhstan
Received September 15, 2011
Abstract—The synthesis and identification of N-[2-(2-morpholinoacetyl)hydrazinocarbothioyl]benzamide
were performed. A qualitative and quantitative evaluation of its complexing ability to the Ni(II) and Co(II) ions
was done. The stability constants of the Ni- and Co-complexes were determined. The thermodynamic aspects
of the complexing process were discussed.
DOI: 10.1134/S1070363212110138
One of the known applications of hydrazides is the
synthesis of thiosemicarbazide derivatives which
possess a broad spectrum of biological activity [1, 2].
In the IR spectrum of compound II there is an
–1
absorption band in the range of 1332–1314 cm
belonging to the C=S bond of the thiosemicarbazide
fragment. The absorption band of the amide group
The isothiocyanate method allows introducing the
thioamide group into the hydrazide structure to obtain
thiosemicarbazides. This method not only extends the
modification of these compounds, but also may lead to
the compounds with new types of bioactivity.
–
1
appears at 1692–1675 cm . An absorption band at
–
1
3
386–3362 cm corresponds to the NH group.
1
The H NMR spectrum of II in DMSO-d
contains
6
a complex multiplet of the aromatic protons at 7.52 ppm.
The amide and thioamide NH-protons are observed as
three broadened singlets at 12.72, 11.80, and 10.65 ppm.
Two triplets at 3.25–3.40 and 3.62–3.70 ppm cor-
respond to the morpholine protons.
In this connection, it is interesting to synthesize
new thiosemicarbazide derivatives based on the N-
morpholinylacetic acid hydrazide I and to study their
complexing ability. Thus, the condensation of benzoyl
isothiocyanate, obtained in situ by heating benzoyl
chloride with potassium thiocyanate in an acetone
medium, with N-morpholinylacetic acid hydrazide I in
an alcohol solution at equimolar ratio of the reagents
results in the thiosemicarbazide derivative II in a 74%
yield. The resulting compound II is a white crystalline
substance soluble in polar organic solvents when
heated.
As indicated above, compound II is soluble in some
polar organic solvents including alcohols, amides and
other compounds containing polar functional groups.
In this work we used a mixture of ethanol and water,
because the solubility of the transition metal salts in
pure polar organic solvents is lower than in water. On
the other hand, this mixture should be regerded as a
two-component solution of water in the amphiprotic
solvents. According to [3], in a solution the primary
structure of water dissociates into the small fragments
and monomers that associate with the alcohol
molecules. Therefore, in a solution there are no free
O
S=C=N C C H
6 5
O
O
N
CH C
+
2
NHNH2
molecules of H O. Thus, the hydration degree of the
I
2
metal ions at the complex formation is very low.
O
S
O
O
N
CH C
Based on the results of potentiometric titration in an
aqueous-alcoholic medium we determined the stability
constants of the d-metal complexes (see the figure).
2
NHNH C NH C C H
6
5
II
1
815

1
816
AMERKHANOVA et al.
log K
(a)
(b)
log K
T, K
T, K
The dependence of the stability constants on the temperature and ionic strength of the complex of N-[2-(2-morpholinoacetyl)hyd-
2
+
2+
–1
razinocarbothioyl]benzamide with the (a) Co and (b) Ni ions in an aqueous-alcoholic medium. Ionic strength, mol l : (1) 0.01,
2) 0.025, (3) 0.05, (4) 0.075, and (5) 0.1.
(
Analysis of the data showed that the increasing
According to [5], for a binary solvent system in the
first solvation shell of the ion the component
dominates, in which the change in the Gibbs energy of
the solvation has a negative value. Since the donor
number of ethanol is lower than that of water, the inner
sphere of the metal ion will contain water, while
ethanol will occupy the outer sphere, or the metal ion
is solvated with the water-ethanol associates. The
nearest solvation is directly connected with the
complex formation process. On the other hand, the
behavior of the ions in a solution is influenced by their
geometric characteristics, such as the ion radius and
temperature and ionic strength have a stabilizing effect
on the complexes of cobalt with N-[2-(2-morpho-
lylacetyl)hydrazinocarbothioyl]benzamide. However, in
the case of the nickel complexes there is the opposite
effect, due to the low complexing ability and the
destructive effect of the above factors on the structure
of the hydration sphere of the complexing metal ion.
In a solution the metal ion is surrounded by the
solvent molecules, which form the inner and outer
spheres [4]. In the temperature range of 298–318 K the
stability constants increase as the concentration of the
supporting electrolyte increases. The maximal effect of
the ionic strength is observed at 318 K. This suggests
that the nitrate ions complete the construction of the
solvation shell of the complex, stabilizing the
complexing metal ion. The stability constants increase
as the temperature increases. This indicates the
necessity of an additional energy for the more stable
complex formation compensated by an increase in the
entropy, which is responsible for the change in the
structure.
When the temperature increases, the stability
constants of the nickel complexes decrease. In this
case the dehydration of the complex takes place, where
the solvent molecules have played a stabilizing role.
The complex stability decreases in the temperature
range of 298–318 K as the concentration of supporting
electrolyte increases. The ionic strength dependence of
the stability constants indicates that the nitrate ions are
involved into the complex formation and form the
bonds directly with the metal ions. The main
thermodynamic parameters of complex formation are
given in Tables 1 and 2.
0
–1
–1
the value of the hydration entropy (–Δ S , J mol K )
h
[
6]. According to the data on the hydration entropy of
2+ 2+
the ions [277.2 (Ni ), 257.6 (Co )], the nickel ion has
a maximal structuring effect on the water molecules,
whereas the cobalt ion has a minimal impact on the
solvent molecules in the near hydrate shell.
For the cobalt(II) ions the ionic strength and
temperature
contribute
to
increasing
the
endothermicity, which explains the associates
formation between the molecules of water and alcohol,
i. e., the solvent has a stabilizing character in relation
to the complex. The increase in ionic strength reduces
the enthalpy. Therefore, the nitrate ions are inserted
into the outer solvation shell of the complex and the
coordination of water molecules occurs, which is the
cause of the weakening of the donor-acceptor bonds
between the solvent and the metal ion and of the
strengthening of the metal-ligand complex.
This fact is connected with the presence of the
2
+
weaker electrostatic field of the Co ion and as a
result, the occurrence of hydrogen bonds with the
solvent molecules. In the case of high temperature, the
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 11 2012

SYNTHESIS AND COMPLEXING ABILITY
1817
0
–1
0
–1
–1
2+
Table 1. The thermodynamic parameters [Δ
r
H (kJ mol ), Δ S (J mol K )] of the complex formation processes of the Со
r
ions with N-[2-(2-morpholinoacetyl)hydrazinocarbothioyl]benzamide in an aqueous-alcoholic medium
0
0
0
0
0
0
0
0
0
0
I
–Δ
h
H
298
–Δ
h
H
303
–Δ
h
H
308
–Δ
h
H
313
–Δ
h
H
318
–Δ
h
S
298
–Δ
h
S
303
–Δ
h
S
308
–Δ
h
S
313
–Δ
h
S
318
0
0
0
0
0
.075
.1
–19.73
–39.15
–20.64
–40.95
–21.55
–42.75
–22.46
–44.56
–23.37
–46.36
237.62
304.53
416.04
527.55
639.06
241.80
312.83
431.20
549.57
667.94
245.99
321.12
446.35
571.58
696.81
251.30
331.67
465.62
599.57
733.51
254.35
337.72
476.66
615.60
754.55
.25
.5
–71.52
–74.81
–78.10
–81.39
–84.68
–103.88
–136.25
–108.66
–142.52
–113.44
–148.78
–118.22
–155.05
–123.00
–161.32
.75
0
–1
0
–1
–1
2+
Table 2. The thermodynamic parameters [Δ
r
H (kJ mol ), Δ
r
S (J mol K )] of the complex formation processes of the Ni
ions with N-[2-(2-morpholinoacetyl)hydrazinocarbothioyl]benzamide in an aqueous-alcoholic medium
0
0
0
0
0
0
0
0
0
0
I
–Δ
h
H
298
–Δ
h
H
303
–Δ
h
H
308
–Δ
h
H
313
–Δ
h
H
318
–Δ
h
S
298
–Δ
h
S
303
–Δ
h
S
308
–Δ
h
S
313
–Δ
h
S
318
0
0
0
0
0
.075
.1
183.79
155.82
109.21
62.59
192.26
163.01
114.24
65.48
200.73
170.19
119.28
68.37
209.2
217.68
184.56
129.36
74.159
18.96
–451.55 –490.54
–366.90 –399.97
–225.83 –249.02
–529.54
–433.04
–272.21
–111.38
49.45
–568.54
–466.11
–295.4
–124.68
46.03
–607.54
–499.18
–318.59
–137.99
42.60
177.37
124.32
71.267
18.21
.25
.5
–84.76
56.30
–98.06
52.88
.75
15.97
16.72
17.46
entropy change is associated with reduction of the
processes of loss of water of its spatial structure at the
distribution of the water molecules in the matrix of an
organic solvent, and also with the strength of the
aggregates with more dense packing of the molecules
interaction of N-[2-(2-morpholinoacetyl)hydrazinocar-
bothioyl]benzamide with the d-metals cations was
studied at 298–313 K (the step of 5 K) by the poten-
tiometric method using the NiS and FeS electrodes.
2
Their selectivity relative to the transition metal ions
was determined in [7]. The reference electrode was a
silver chloride electrode. The electromotive force was
measured on an I-500 pH metermillivoltmeter. The
potentiometric titration of 0.001 M. solutions of the d-
metals salts with 0.001 M solution of N-[2-(2-
morpholinoacetyl)hydrazinocarbothioyl]benzamide was
carried out by the known method [7]. In order to
maintain the desired temperature we used an UTU-
[
3]. This leads to the complex stabilization.
In the case of nickel(II) ions, an increase in the
temperature contributes to increasing the exothermic
process, i. e., the decrease in the complex stability is
accompanied by changing the solvate environment, in
particular, the release of the water molecules from the
first and second solvation shell of the complexing
metal ion or the rearrangement of water and an organic
solvent in the inner and outer solvation shells of the
complex. Since the nickel ion has a high polarizing
power, the change in the composition of the near
solvation sphere via the temperature increase or the
introduction of the nitrate ions leads to destabilizing
the structure of the complex. In the first case, it is due
to the formation of the complexes with the covalent
bonding, and in the second, of the complexes of the
electrostatic nature.
2
/77 thermostat with an accuracy of ±0.1 K.
The IR spectra were recorded on an Avatar-320
1
Nicolet FT-spectrometer (KBr). The H NMR spectra
were registered on a Bruker DRX500 spectrometer
(
500 MHz) in DMSO-d relative to the internal TMS.
6
The synthesis of compound I was performed by
procedure [8].
N-[2-(2-Morpholinoacetyl)hydrazinocarbothioyl]-
benzamide (II). To a solution of 0.43 g of benzoyl
chloride in 5 ml of acetone was added under stirring
EXPERIMENTAL
0
.31 g of potassium thiocyanate. The reaction mixture
The potentiometric study of the complexing
was stirred for 2 h and filtered through a paper filter.
Then to the filtrate was added 0.5 g of N-mor-
pholylacetic acid hydrazide in 5 ml of anhydrous iso-
propyl alcohol. The mixture was stirred at 60°C for 3 h.
After the solvent removal, the residue was recrys-
ability. We used in the study Co(NO ) and NiCl of
3
2
2
chemically pure grade, and N-[2-(2-morpholinoacetyl)-
hydrazinocarbothioyl]benzamide. The compounds were
dissolved in 70% aqueous solution of ethanol. The
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 11 2012

1
818
AMERKHANOVA et al.
tallized from 2-propanol on cooling. Yield 0.74 g
2. Soldatenkov, A.T., Kolyadina, N.M., and Shendrik, I.V.,
Osnovy organicheskoi khimii lekarstvennykh veshchestv
(
74%), white crystalline solid, mp 187–188°C. Found,
: C 52.38, H 5.84; N 17.50. С Н N O S. Ca-
(
Fundamentals of Organic Chemistry of Drugs),
%
1
4
18
4
3
Moscow: Khimiya, 2001.
lculated,%: C 52.16; H 5.63; N 17.38. M 322.
3
.
Kessler, Yu.M., Petrenko, V.E., and Lyashchenko, A.K.,
Voda: struktura, sostoyaniye, sol’vatatsiya. Dos-
tizheniya poslednikh let (Water: Structure, State, Sol-
vation. Advances in Recent Years), Moscow: Nauka,
2003.
Thus, N-[2-(2-morpholinoacetyl)hydrazinocarbo-
thioyl]benzamide, a representative of a large class of
the nitrogen- and sulfur-containing organic compounds
such as thiosemicarbazide with a wide range of useful
properties, was synthesized. The studies of the
complex formation of the transition metal ions with an
organic component in a water-alcohol mixture revealed
a linear relationship between the stability constants of
the complexes and thermodynamic characteristics of
the ions in the solution. According to the data on the
thermodynamics of the complex formation, the degree
of structuring of the solvent along with the nature of
the complexing metal ion has a significant influence on
the complex formation in a solution. At high tem-
peratures this leads to an increase in the hydration
number. Therefore, the introduction of the cobalt(II)
ion not only increases the stability of the structure of
the organic ligand in an aqueous-alcoholic medium,
but also helps to increase the complex solubility,
which can be used in the synthesis of the biologically
active drugs or enzyme systems.
4. Kumok, V.N., Zakonomernosti v ustoichivosti koordi-
natsionnykh soedinenii v rastvorakh (Regularities in the
Stability of Coordination Compounds in Solution),
Tomsk: Tomsk. Gos. Univ., 1988, p. 227.
5
.
Kompleksoobrazovanie v nevodnykh rastvorakh (Com-
plexation in Non-Aqueous Solutions), Krestov, G.A.,
Afanas’ev, V.N., and Agafonov, A.V., Eds., Moscow:
Nauka, 1989.
6
7
.
.
Amerkhanova, Sh.K., Sal’keeva, L.K., Shlyapov, R.M.,
Minaeva, E.V., and Uali, A.S., Zh. Obshch. Khim.,
2
010, vol. 80, no. 6, p. 1028.
Amerkhanova, Sh.K., Khal’kogenidy metallov v poten-
tsiometrii. Teoriya, metodika, praktika. (Metal
Chalcogenides in Potentiometry. Theory, Methodology,
Practice), Karaganda: Profobrazovaniye, 2002.
8
.
Nurkenov, О.А., Satpaeva, Zh.B., and Kulakov, I.V.,
Abstract of Papers, IV Mezhdunarodnaya nauchnaya
konferentsiya “Innovatsionnoe razvitiye
i
vostre-
bovannost’ nauki v sovremennom Kazakhstane” (IV Int.
Sci. Conf. “Innovationing Development and Relevance
of Science in Modern Kazakhstan”), Almaty, 2010,
p. 104.
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RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 11 2012