Synthesis, Spectral, X-Ray Diffraction, DFT, and Nematicidal Activity of Mixed Ligand Complexes of Ethyl 2-(2-Hydroxybenzylidine)-Hydrazine Carboxylate and 1,10-Phenanthroline with Some Transition Metals

Article abstract of DOI:10.1002/jccs.201700176

In this work, mixed ligand complexes derived from ethyl 2-(2-hydroxybenzylidine)-hydrazine carboxylate (HL) and 1,10-phenanthroline (Phen) as ligands were synthesized and their structures elucidated by elemental analysis, infrared (IR), electronic,^1<

Full text of DOI:10.1002/jccs.201700176

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Article
Synthesis, Spectral, X-Ray Diffraction, DFT, and Nematicidal Activity of Mixed Ligand
Complexes of Ethyl 2-(2-Hydroxybenzylidine)-Hydrazine Carboxylate and
1,10-Phenanthroline with Some Transition Metals
a,b* a
a
Wael Abd-allah Zordok ,
Sadeek Atia Sadeek, Ahmed F. El-Farargy and
c
Nossa S. Abd El-Lattif
a
Department of Chemistry, Faculty of Science, Zagazig University, Zagazig, Egypt
b
Department of Chemistry, University College of Quanfudha, Umm Al-Qura University, KSA, Quanfudha, Saudi
Arabia
c
Department of Pesticides Formulation, Central Agricultural Pesticides Laboratory, Cairo, Egypt
(Received: May 23, 2017; Accepted: August 28, 2017; DOI: 10.1002/jccs.201700176)
In this work, mixed ligand complexes derived from ethyl 2-(2-hydroxybenzylidine)-hydrazine car-
boxylate (HL) and 1,10-phenanthroline (Phen) as ligands were synthesized and their structures elu-
1
cidated by elemental analysis, infrared (IR), electronic, H NMR, and mass spectra, X-ray
diffraction (XRD), magnetic susceptibility measurements, and TG/DTG analyses. The analytical
and spectral data support the formation of the complexes with the central ion in each complex six-
coordinated and a slightly distorted octahedral geometry. The IR spectra showed that HL and
Phen ligands act as neutral bidentates. The XRD patterns of the complexes showed their crystal-
line nature. The calculated bond length and the force constant F(U═O) in the uranyl complex are
−
1
1
.738 Å and 685.90 Nm , respectively. The molar conductance values of the synthetic complexes
2
in DMF were found to be in the range 5.00–274.06 S cm /mol at room temperature. The thermo-
dynamic parameters were evaluated by using the Coats–Redfern (CR) and Horowitz–Metzeger
(HM) methods. Theoretical molecular structures were investigated by the density functional the-
ory/B3LYP method using the Gaussian 98 W basis set. The nematicidal activity of the ligands and
its metal complexes was also studied.
Keywords: Schiff base; Phen; Thermal analysis; X-ray diffraction; Density functional theory;
Nematicidal.
INTRODUCTION
Schiff bases represent an important class of com-
Complexes involving a Schiff base and 1,10-
phenanthroline (Phen) has been studied extensively.
8,13
pounds because they are utilized as starting materials in
the synthesis of industrial products. Schiff base ligands
Bidentate N,N-chelating agents such as Phen have
played an important role in synthetic and medicinal
chemistry, analytical and preparative coordination
1
and their metal complexes play a key role in under-
standing the coordination chemistry of transition-metal
chemistry, as well as in the preparation of many mixed-
2,3
14–16
ions. In the past, several Schiff base metal complexes
ligand complexes.
Consequently, ligands containing
1–7
have been studied because of their wide applicability.
nitrogen have broad applications in forming stable
complexes with a wide variety of metal ions, some of
which have also been found to exhibit interesting physi-
cochemical and chemotherapeutic properties, and in
In addition, the presence of nitrogen and oxygen donor
atoms in the complexes makes these compound highly
effective as carcinostatic, antitumor, and antiviral
agents, and makes them interesting models for metal-
loenzymes, stereospecific catalysts for oxidation, reduc-
tion, and hydrolysis. They also show biological
1
7–21
asymmetric catalysis.
Phytoparasitic nematodes are
2
2
among the most difficult crop pests to control ; they
severely damage a wide range of agricultural crops,
causing serious yield losses worldwide, especially in the
7–12
activity.
*Corresponding author. Email: wazordok@yahoo.com
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1

Article
Zordok et al.
tropical and subtropical regions where environmental
and thermogravimetry. The results of elemental analysis
(Table 1) agree quite well with the speculated formula
of the complexes and suggest that complexes are
2
3
factors favor their survival and dispersal. Therefore
there is increasing interest in discovering new nematici-
dal compounds.
formed in 1:1:1 ratio. The ligands have N O in case of
3
This work deals with the synthesis of metal com-
plexes from mixed ethyl 2-(2-hydroxybenzylidine)-
hydrazine carboxylate (HL) (Scheme 1a) as the primary
ligand and Phen (Scheme 1b) as the secondary ligand.
The structures of the studied complexes are character-
ized using different spectral analytical techniques (infra-
Cu(II), Y(III), Zr(IV), La(III), and U(VI), or N O in
2
2
case of Co(II) complex cores (nitrogen of azomethine,
phenolic O atom of HL, and two azomethine nitrogen
atoms in Phen or two azomethine nitrogen atoms in
Phen, phenolic O atom, and keto O atom in HL
ligand). The magnetic moments (as B.M.) of the com-
plexes were measured at room temperature. Their
values for the complexes indicate the presence of one
unpaired electron in Co(II) (low spin) with a value 1.80
B.M. and in Cu(II) ion with 2.25 B.M., whereas the
other complexes were found to be diamagnetic. The
thermogravimetric and IR spectroscopic data also con-
firm the presence of water in the composition of the
complexes. The molar conductance values of the com-
1
red [IR], UV–vis, H NMR, and mass spectra), X-ray
diffraction (XRD), melting point, elemental analysis,
molar conductivity, and thermal analyses. The kinetic
parameters were calculated for the ligands and their
complexes. The nematicidal activity of the investigated
complexes and free ligands were studied. The optimal
set and geometry of these complexes were studied by
using density functional theory (DFT) to investigate the
influence of Co(II), Cu(II), Y(III), Zr(IV), La(III), and
U(VI) cation types on theoretical parameters of mixed
ligands (HL and Phen) and complexes and elucidate the
exact structure of these complexes with different coordi-
nation numbers using the Gaussian 98 W package of
plexes were found
to be in
the range
2
15.00–272.06 S cm /mol at room temperature (Table 1).
Qualitative reactions also agree well with the molar
conductance data, which revealed the presence of chlo-
ride and acetate ions as counterions. Solutions of the
complexes were tested with an aqueous solution of
AgNO and FeCl .The nematicidal activity of the com-
24
25
programs at B3LYP/CEP-31G level of theory.
3
3
pounds was also studied.
RESULTS AND DISCUSSION
Characterization of the mixed ligand and their
complexes
IR absorption spectra
The IR spectral data for HL, Phen, and their
metal complexes are summarized in Table S1
The mixed-ligand complexes 1–6 were synthesized
in absolute ethanol as colored powders, which were sta-
ble in air and had high melting points. They are freely
soluble in DMSO and DMF and sparingly soluble in
methanol and ethanol. The metal complexes were char-
acterized by elemental analysis, magnetic susceptibility,
(
Supporting information). The IR spectra (Figure S1)
of the complexes in comparison with free ligand and
the respective Phen were examined to determine the
coordination sites that may be involved in chelation,
which showed characteristic bidentate HL and Phen
chelation. The spectral absorption bands around
1
XRD, IR, mass, UV–vis, and H NMR spectroscopy,
−
1
3
442 cm
correspond to the ν(O–H) vibration in
HL. The shift of ν(O–H) in all complexes indicates
the coordination of phenolic group with metal ions
and also confirms the presence of water molecules
26–29
associated with the complex formation.
The ν(N–
H) stretching vibration band is observed in the range
−
1 30
−1
3
238–3242 cm . Further, the band at 1714 cm in
the spectrum of HL is assigned to υ(C═O). The
appearance of this band in complexes 2–6 indicates
that carbonyl group is free from complexation. How-
ever, in case of complex 1, the shift of υ(C═O) to a
Scheme 1. (a) Ethyl 2-(2-hydroxybenzylidine)-
hydrazine carboxylate(HL), (b) 1,10-
phenanthroline (Phen).
2
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
higher wave number indicates that coordination
31
occurs through the oxygen of the carbonyl group
and phenolic oxygen with Co(II). The bands observed
−
1
at 1620 and 1586 cm are assigned to C═N group
for HL and Phen. The shift of υ(C═N) to lower or
higher frequency in complexes 2–6 indicates the par-
ticipation of the mixed ligand in the coordination and
the formation of a bond between the nitrogen of HL
and nitrogen of Phen with the central metal ions,
which further prove that HL and Phen act as biden-
32–35
tate ligands (Scheme 2).
On the other hand, in
the case of complex 1, υ(C═N) remained unchanged,
which indicates that the (C═N) group is free from
complexation. From the above data, the HL ligand
acts as bidentate bonding to the metal ion via pheno-
lic oxygen and imine nitrogen in case of Cu(II),
Y(III), Zr(IV), La(III), and U(VI) and to Co(II) via
the phenolic oxygen and carboxyl oxygen. Also, Phen
acts as a bidentate ligand, which contains two nitro-
gen donor atoms, forming five and/or six rings includ-
ing the metal ions. The coordination of the metal ions
via nitrogen and oxygen of HL is also confirmed by
the υ(M–O) and υ(M–N). These bands are observed
−
1
at 634, 512, and 474 cm
for Co(II); 662, 595,
−
1
5
4
4
51, 513, 479, and 432 cm for Cu(II); 645, 593, and
−
1
74 cm
31 cm
for Y(III); 673, 641, 593, 555, 454, and
for Zr(IV); 631, 613, and 475 cm
−
1
−1
for
Scheme 2. The coordination mode of Co (II), Cu
II), Y (III), La (III), Zr(IV), and U(VI)
with HL and Phen.
(
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
3

Article
Zordok et al.
−
1
La(III); and 638, 593, 521, 484, and445 cm
for
UV–visible absorption spectra
U(VI) (Table S1), whereas they are absent in the spec-
trum of the ligand.
Electronic absorption spectra of the synthesized
compounds were recorded in DMF solution in the
wavelength range 200–800 nm (Figure 1). It can be seen
that HL and Phen show bands at 275, 284, 318, 273,
and 350 nm, respectively. The bands at 275, 284, and
The data in Table S1 shows that ν(Zr═O) is a
−
1
medium strong band at 846 cm and the ν (U═O) is a
as
−1
very strong band at 898 cm , and the corresponding
ν (U═O) is a medium strong band at 842 cm . These
−1
*
273 nm may be assigned to π–π , while those at
s
*
41,42
assignments for the stretching vibrations of the uranyl
group agree quite well with those known for many
318 and 350 nm to n–π transitions
(Table 2). The
shift of the absorption bands to higher or lower wave
numbers and the appearance of new bands for the com-
plexes are attributed to the coordination of the two
ligands metal ions forming mixed ligand complexes.
Also, complexes 1–6 showed new bands at 400, 410,
380, 420, 430, and 415 nm, respectively, which may be
assigned to the ligand-to-metal charge transfer
3
6–38
dioxouranium(VІ) complexes.
The ν (U═O) value
s
was used to calculate both the U═O bond stretching
3
9,40
force constant F(U═O) and the bond length.
The
calculated bond length and force constant are 1.738 Å
−
1
and 685.90 Nm , respectively
4
3–45
(
L ! M).
According to the UV–vis results, d–d
transitions attributable to Co(II) and Cu(II) complexes
4
4
are observed at 572 nm ( T g ! T g) (F) and 547 nm
1
2
4
4
(
T g ! T g) (P), respectively, favoring octahedral
1
1
46–48
geometry.
1
H NMR spectra
1
The H NMR spectral data of HL, Phen ligands,
and their metal complexes were measured in DMSO
1
(
Table 3). The H NMR spectrum of HL (Figure 2)
showed a singlet at δ = 6.85–6.89 ppm, corresponding
to –CH aliphatic, a multiplet at δ = 7.22–8.23 ppm for
–CH aromatic, a triplet at δ = 1.22 ppm corresponding
to (3H, CH ), a quarteret at δ = 2.51 ppm correspond-
3
ing to (2H, CH ), a singlet at δ = 10.87 ppm corre-
2
sponding to –NH of the amide group, and a singlet at
δ = 11.25 ppm corresponding to (H, OH). The data
obtained confirmed the formation of ethyl 2-(2-hydro-
xybenzylidine)-hydrazine carboxylate (HL) (Scheme 1).
1
Moreover, the H NMR spectra of the complexes 1–6
showed that the signals attributed to (NH) and
(OH) protons remained more or less at the same posi-
tions, indicating that these groups were not deproto-
nated. On comparing the main peaks of HL and Phen
with its complexes, it is observed that all the peaks of
HL are present in the spectra of the complexes with
chemical shift upon binding of the free ligand to the
Fig. 1. Electronic absorption spectra of (a) HL
,
(
b) Phen, (c) [Co(HL)(Phen)(H
2
O)
](CH COO)
O, (f) [ZrO(HL)
2
]Cl
2
.H
2
O,
(e)
(
d) [Cu(HL)(Phen)(H
O) ]Cl
.2H
H O) ]Cl .8H O, and (h) [UO (HL)(phen)
2
O)
2
3
2
,
49
1
metal ion. Also, the H NMR spectra for complexes
exhibit new peaks in the range 3.31–4.38 ppm, which
are due to the presence of water molecules in the
[
Y(HL)(Phen)(H
2
2
.8H
3 2
(
(
(
Phen)(H
2
O)]Cl
2
2
O, (g) [La(HL)(Phen)
2
2
3
2
2
50,51
H O)](CH COO) .
complexes.
2
3
2
4
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
Table 2. UV–vis spectra of HL, Phen, (1) [Co(HL)(Phen)(H O) ]Cl .H O, (2) Cu(HL)(Phen)(H O) ](CH COO) , (3) [Y(HL)
2
2
2
2
2
2
3
2
(
Phen)(H O) ]Cl .8H O, (4) [ZrO(HL)(Phen)(H O)]Cl .2H O, (5) [La(HL)(Phen)(H O) ]Cl .8H O, and (6) [UO (HL)
2
2
3
2
2
2
2
2
2
3
2
2
(
phen)(H O)](CH COO)
2
3
2
Ligand–
Ligand
metal
charge
transfer
transitions
d–d
*
*
−1
−1
(
π–π
n–π )
ν−1 ϵM
Transition
ν−1
−1ϵ
and
−1
−1
Compounds
λmax (nm)
ν (cm
)
(λmax [nm]) (cm ) ( cm
)
(λmax [nm]
)
(cm ) (M cm
)
HL
Phen
275, 284, 318
273, 350
36 363, 35 211, 31 446
36 630, 28 571
—
—
—
—
—
—
—
—
—
—
—
—
(1)
(2)
(3)
(4)
(5)
(6)
274, 283, 317
275, 284, 312, 359 36 363, 35 211, 32 051, 27 855
275, 284, 318
298, 358
275, 284, 317
272, 294, 339
36 496, 35 335, 31 545
400
410
380
420
430
415
25 000 690
24 390 310
26 315 170
23 809 210
572
547
—
17 482
18 281
—
460
360
—
36 363, 35 211, 31 446
33 557, 27 932
36 363, 35 211, 31 545
36 764, 34 013, 29 498
—
—
—
23 256
60
—
—
—
24 096 800
—
—
—
Thermal analyses
Phen undergoes decomposition in two stages. The
The mixed ligand HL and Phen of complexes 1–6
are stable at room temperature and can be stored for
several months without any changes. To establish the
proposed formulas of the synthesized complexes, TG
and DTG methods were employed. The TG and DTG
curves of HL and its complexes are shown in Figure 3.
first stage is accompanied by a mass loss of 8.02% and
ꢀ
the maximum rate occurs at 95 C. The second decom-
ꢀ
position stage occurs at 278 C with a mass loss of
52
91.98% corresponding to the loss of 5C H + C N ,
2
2
2
2
with an activation energy 118 kJ/mol.
The TG curve of the Co(II) complex shows three
ꢀ
The temperature values (Tmax in C) together with the
weight loss events. The first stage of decomposition occurs
ꢀ
corresponding weight loss for each step of the decom-
position reactions of the above compounds are listed in
Table S2.The thermal decomposition of HL started at
in the range 33–144 C, with two maxima at 50 and
ꢀ
120 C corresponding to the loss of one water molecule of
hydration. The second stage of decomposition occurs in
ꢀ
ꢀ
ꢀ
7
3 C and finished at 800 C and took place in one
the range 145–305 C, with a mass loss 38.02% (Calc.
ꢀ
stage with two DTG peaks 227 and 554 C and accom-
panied by a weight loss 99.74%, corresponding exactly
to the loss of 2.5C H + 3CO + 2HCN, which is very
37.77%), due to the removal of 2NO + 6C H ; the activa-
2
2
tion energy for this process is 182 kJ/mol. The third stage
ꢀ
of decomposition occurs at 692 C with a mass loss
2
4
close to the calculated value of 100%. The maximum
rate of mass loss is indicated, and the value of the
energy of activation for this process is 84 kJ/mol.
45.40% (Calc. 45.98%), corresponding to the removal of
2NO + 2HCl + 5C H and giving CoO as the final prod-
2
2
uct with a weight loss of 13.49% (Calc. 13.11%).
1
Table 3. H NMR values (ppm) and tentative assignments for HL, Phen, (1) [Co(HL)(Phen)(H
2
O)
2
]Cl
2
.H
2
O, (2) Cu(HL)(Phen)
(
H
2
O)
2
](CH
3
COO)
2
, (3) [Y(HL)(Phen)(H
2
O)
2
]Cl
3
.8H
2
O, (4) [ZrO(HL)(Phen)(H
COO)
2
O)]Cl
2
.2H
2
O, (5) [La(HL)(Phen)
(
H
2
O)
2
]Cl .8H
3
2
O, and (6) [UO
2
(HL)(phen)(H
2
O)](CH
3
2
HL
Phen
11.25
—
10.87
7.22–8.23
7.20–8.80
7.13–8.17
7.23–8.23
7.00–8.99
7.19–8.61
7.19–8.57
6.85–6.89
—
—
—
2.51
—
1.22
—
(1)
(2)
(3)
(4)
(5)
(6)
11.21
11.25
11.12
11.21
11.12
11.21
10.78
10.85
10.85
10.93
10.94
10.97
6.76–6.81
6.87
6.97–6.99
6.82–6.93
6.82–6.94
3.50–4.08
3.31–4.16
3.33
3.42–4.178
3.38–4.18
3.31–4.38
2.50
2.50
2.50
2.51
2.51
1.13
1.24
1.24
1.20
1.20
7.45–8.99
6.66–6.92
2.51
1.35
(
s)
(s)
(m)
(s)
Assignments
δ, OH
δ, −NH
δ, −CH aromatic
δ, −CH HC═N
δ, H
2
O
δ, −CH
2
δ, −CH
3
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
5

Article
Zordok et al.
The TG curve of complex 2 showed three stages
which is due to the removal of CO + NO + 3C H +
2
2
of decomposition. The first stage occurred in the range
C H + 0.5 N , and giving CuO + C as a final product
2 6 2
with a weight loss of 15.00% (Calc.15.11%).
ꢀ
40–138 C, with a mass loss is19.35% (Calc. 19.49%).
The maximum rate of mass loss indicated by the DTG
The complex 3 undergoes decomposition in three
stages. The first stage of decomposition occurred in the
range 33–117 C, with a mass loss of 18.80% (Calc.
ꢀ
peak is at 111 C, due to the removal of C H + 2CO .
2
6
2
ꢀ
The second stage of decomposition occurred in
ꢀ
1
39–365 C with a mass loss of 35.56% (Calc. 35.67%)
18.86%) with the maximum temperatures of 86 and
ꢀ
ꢀ
and the maximum rate of mass loss was at 211 C, due
to the loss of 2NO + 6C H , with an activation energy
132 C, due to the removal of 8H O, and the value of
2
activation energy for the dehydration process is 52 kJ/
mol. The second step of decomposition occurred in the
2
2
6
1 kJ/mol. The third stage of decomposition occurred
ꢀ
ꢀ
at 554 C, with the maximum rate of mass loss indi-
cated by the DTG peak of 30.09% (Calc. 29.73%),
range 117–317 C, with a mass loss of 28.19% (Calc.
28.29%) with the maximum rate of mass loss indicated
ꢀ
by the DTG peaks at 255 and 379 C, due to the
removal of 2NO + 6C H . The third step of decompo-
2
2
ꢀ
sition occurred in the range 319–818 C, with a mass
1
Fig. 2. H NMR spectra for (a) HL
,
(b) Phen,
O, (d) [Cu
, (e) [Y(HL)
O, (f ) [ZrO(HL)(Phen)
O, (g) [La(HL)(Phen)(H O)
Fig. 3. TGA and DTG diagrams for (a) HL,
(b) Phen, (c) [Co(HL)(Phen)(H O) ]Cl .H O,
(
(
(
(
c) [Co(HL)(Phen)(H
HL)(Phen)(H O) ](CH
Phen)(H O) ]Cl .8H
O)]Cl .2H
2
O) ]Cl .H
2 2 2
2
2
2
2
2
2
3
COO)
2
2 2 3 2
(d) [Cu(HL)(Phen)(H O) ](CH COO) , (e)
[Y(HL)(Phen)(H O) ]Cl .8H O, (f ) [ZrO(HL)
2 2 3 2
(Phen)(H O)]Cl .2H O, (g) [La(HL)(Phen)
2 2 2
2
2
3
2
H
2
2
2
2
2
]
Cl .8H O, and (h) [UO (HL)(phen)(H O)]
(H O) ]Cl .8H O, and (h) [UO (HL)(phen)
3
2
2
2
2
2
3
2
2
(
CH COO) .
2 3 2
(H O)](CH COO) .
3
2
6
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
loss of 35.08% (Calc. 34.92%) corresponding to the loss
of NO + 4C H + 3HCl + 0.5H O + 0.5 N , giving
YO1.5 + 2C as a final product.
complementary technique (gas chromatography). The
suggested residues were confirmed only on the basis
weight loss percentage calculation.
2
2
2
2
The TG curve of 4 exhibits three main degrada-
Kinetic studies
tion steps. The first step of decomposition occurred in
ꢀ
The kinetic parameters were calculated by
employing the Coats–Redfern and Horowitz–Metzger
equations, as summarized in Table S3. The thermody-
namic data obtained by these two methods are in har-
the range 29–88 C with a mass loss of 5.81% due to
the removal of 2H O. The second step of decomposi-
2
ꢀ
tion occurred in the range 89–244 C with a mass loss
of 31.92%, corresponding to the loss of 5C H +
2
2
54,55
C N + 0.5O ; the value of activation energy for this
mony with each other
and the results obtained by
2
2
2
process is 93 kJ/mol. The third step of decomposition
these methods are comparable. The following two
methods are briefly discussed.
ꢀ
occurs in the range 244–572 C, with one maximum at
ꢀ
5
06 C with a mass loss 26.92% due to the removal of
NO + 2CH + H + 2HCl; the value of activation
54
Coats–Redfern (CR) Equation
The CR equation
2
4
2
(Eq. (1)), which is a typical integral method, can be
energy for this step is 43 kJ/mol, and the final solid
represented as
5
3
product is ZrO + 8C.
2
The TG curve of 5 shows three stages of decompo-
α
T2
ꢀ
ꢁ
ð
ð
ꢀ
dα
ð1−αÞ
A
φ
−E*
RT
sition. The first step occurred in the range 36–68 C, with
=
exp
dT
ð1Þ
n
ꢀ
a maximum at 68 C, and was accompanied by a weight
0
T1
loss of 17.06% (Calc. 17.70%), due to the removal of
hydrated water. The second step of decomposition
ꢀ
occurred at the maximum temperature of 197 C and
For convenience of integration, the lower limit T
is usually taken as zero. On integration it gives
1
was accompanied by a weight loss of 26.94% (Calc.
2
6.56%) due to the removal of 2NO + 6C H . The third
2 2
"
ꢂ
#
ꢀ
1−n
ꢂ
ꢃ
step of decomposition occurred in the range 400–762 C,
with two maxima at 362 and 455 C, and was accompa-
nied by a weight loss of 30.80%(Calc. 29.81%), due to
the loss of 0.5H O + Cl O + 2HCN + 2C H + HCl,
giving LaO1.5 + 4C as a final product. The value of the
activation energy for this step is 201 kJ/mol.
−E*
−
lnð1−αÞ
AR
ꢀ
ln X = ln
=
+ ln
for n
6¼ 1
2
ϕE*
T ð1−nÞ
RT
ð2Þ
2
2
2
4
The TG curve of 6 exhibits three main degrada-
ꢃ
ꢂ
ꢃ
tion steps. The first step occurred with a maximum at
2
1
− lnð1−αÞ
−E*
RT
AR
ϕE*
ln X = ln
=
+ ln
for n = 1
ꢀ
2
91 C and was accompanied by a weight loss of
4.79% (Calc. 14.86%), due to the volatile C H + 2
T
2
6
ð3Þ
CO2 molecules. The second step of decomposition
occurred in the range 434–641 C, and was accompa-
ꢀ
where Φ is the linear heating rate dT/dt, R is the gas
constant (in J/k/mol), and α is the fraction decom-
posed at time t. The correlation coefficient (r) was
computed using the least squares method for different
values of n (0, 0.33, 0.5, 0.66, and 1) by plotting ln
X vs. 1/T for the investigated metal complexes, as
shown in Figure S3. E* is the energy of activation
(in kJ/mol) and calculated from the slope, and A in
nied by a weight loss of 24.98% (Calc. 24.94%), due to
the loss of C N + 0.5O + 5C H molecules; the value
2
2
2
2
2
of activation energy for this step is 78 kJ/mol. The third
step of decomposition occurred with the maximum rate
ꢀ
of mass loss indicated by the DTG peaks at 690 C and
was accompanied by a weight loss of 24.98% (Calc.
2
4.94%), due to the removal of 2NO + 0.5O + 2C H
2 2 6
giving UO + 6C with a weight loss 42.73% (Calc.
2
−
1
43.07%) as the final product.
(s ) is obtained from the intercept. The entropy of
activation ΔS* (in kJ/mol K) was calculated by
using Eq. (4):
The decomposition mechanisms are only based on
speculation and thermal analysis without the use of a
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
7

Article
Zordok et al.
ꢀ
ꢁ
X-ray diffraction
Ah
*
ΔS = R ln
ð4Þ
XRD is a tool to distinguish crystalline from non-
crystalline (amorphous) materials and gives information
about the unit cell structure, lattice parameters, and
Miller indices. Generally, sharp, narrow, and intense
peaks suggest high purity and crystallinity. The crys-
tal structures of HL, Phen, and the complexes 1–6 were
characterized by XRD and recorded over the scanning
kBTs
where k is the Boltzmann constant, h is the Plank con-
stant, and T is the DTG peak temperature.
B
s
58
5
5
Horowitz–Metzger (HM) Equation
The HM equa-
tion is an illustration of approximation methods. These
authors derived the relation
ꢀ
range 2θ = 10–70 (Figure 4). The data were recorded
for HL and Phen as ligands, which are crystalline as
they contain sharp peaks, as reported in Table 4.
The diffractogram of complex 1 shows crystalline
peaks at 2θ (d-value in Å) = 7.90 (11.19), 8.24 (10.73),
Eaθ
RT2s
ln½− lnð1−αÞꢁ =
for n = 1
ð5Þ
ð6Þ
1
2
3.42 (6.59), 15.69 (5.65), 18.35 (4.84), 20.89 (4.25),
3.91 (3.72), 25.27 (3.52), 26.09 (3.41), and 27.63 (3.23).
n
o
2
4
3
5
1
−n
ꢀ
ꢁ
For complex 2, sharp peaks appear at 2θ (d-value in
1
−ð1−αÞ
ð1−nÞ
ART2s
Φ E
Ea
ln
= ln
−
RTs
Eaθ
RT2s
+
for n
6¼ 1
where θ = T – T , with T being the DTG peak temper-
s
s
ature. T is the temperature corresponding to the weight
loss. In this method, a straight line should be observed
between the left-hand sides of Eqs. (5) and (6) vs. θ with
2
s
the slope E /RT . The entropy of activation ΔS*, the
a
enthalpy of activation ΔH*, and Gibbs free energy
ΔG* were calculated as follows:
*
*
ΔH = E – RT
ð7Þ
and
*
*
*
ΔG = ΔH – TΔS
ð8Þ
It is clear that the thermal decomposition of the
six complexes indicate that they are thermally stable.
The positive ΔH* values postulate the endothermic
nature of the formed complexes. The negative value of
the entropy of activation (ΔS*) for the decomposition
steps indicates that the activated fragments have a more
ordered structure. The greater positive values of E*
indicate that the processes involves translational, rota-
tional, vibrational states, and a changes in mechanical
Fig. 4. X-ray diffraction pattern for (a) HL (b) Phen,
,
(c) [Co(HL)(Phen)(H
2
O)
](CH COO)
.8H O, (f ) [ZrO(HL)(Phen)
2
O, (g) [La(HL)(Phen)(H O) ]
2
]Cl
2
.H
2
O, (d) [Cu
(
(
(
HL)(Phen)(H
Phen)(H O) ]Cl
O)]Cl .2H
2
O)
2
3
2
, (e) [Y(HL)
2
2
3
2
H
2
2
2
2
Cl .8H O, and (h) [UO (HL)(phen)(H O)]
3
2
2
2
5
6,57
potential energy of the complexes.
(CH
3
COO) .
2
8
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
Table 4. The average crystallite size of the synthesized compounds estimated from XRD pattern
Relative
intensity (%)
Full width at half 1
Average crystallite
size (nm)
ꢀ
Complexes
HL
2θ ( )
d-Value (Å)
maximum (FWHM)
25.97
25.27
11.46
14.72
11.30
8.25
3.43
3.52
7.72
6.02
7.83
100
100
100
100
100
100
100
0.22
0.20
0.33
0.14
0.16
0.33
0.12
0.69
0.76
0.43
1.06
0.86
0.42
0.14
(
(
(
(
(
(
1)
2)
3)
4)
5)
6)
10.72
12.39
7.14
1
The maximum diffraction patterns according to the highest value of intensity.
Å) = 8.23 (10.74), 8.94 (9.89), 11.46 (7.72), 14.31
their complexes with 5000 ppm against migration of
second-stage larvae of the root-knot nematode
M. javanica was studied under laboratory conditions,
and the obtained results were presented in Figure S4
and listed in Table 5. Both ligands (HL and Phen)
recorded almost the same percentage inhibition (7.5
and 7.8, respectively). On the other hand, all complexes
except 3 showed higher nematicidal activity than the
ligands. The highest effect was recorded with 1, fol-
lowed by 5, 4, 2, and 6. The reactive inhibition percen-
tages were 85.6, 76.1, 72.9, 57.7, and 27%, respectively.
In contrast, 3 did not possess any nematicidal effect; it
recorded zero inhibition percentage. The obtained
results are agreement with those in the literature that in
most cases the free ligands do not have any nematicidal
activity but most metal complexes show higher activity
against the tested nematode, indicating that complexa-
(
(
6.19), 19.41 (4.57), 23.39 (3.80), 26.07 (3.42), and 28.31
3.15). For complex 3, the main crystalline peaks are at
2θ (d-value in Å) = 8.31 (10.64), 10.86 (8.15), 14.72
(
(
6.02), 17.47 (3.61), 21.30 (5.08), 24.70 (4.17), and 26.16
3.41). Complex 4 gives peaks at 2θ [d-value in
Å) = 11.30 (7.83), 15.27 (5.80), 21.45 (4.14), 22.84
(
(
3.90), and 26.77 (3.33). Complex 5 shows peaks at 2θ
d-value in Å) = 8.25(10.72), 9.74 (9.07), 13.57 (6.52),
2
6.09 (3.42), and 37.14 (2.42). Complex 6 shows five
sharp peaks at 2θ [d-value Å) = 7.14 (12.39), 9.12
9.70), 14.36 (6.17), 14.66 (6.04), and 28.78 (3.10).
(
Based on previous data, all compounds are crystalline
in nature.
Biological activity
Root-knot nematodes Meloidogyne spp. are obli-
gate parasites and are very damaging plant pests, limit-
ing agricultural productivity. Most cultivated plant
species are susceptible to root-knot nematode infec-
60
tion occurs.
Computational studies
59
The central metal ion is chelated with the Phen
ligand through two coordinated bonds (N9 and N12
atoms), and the HL ligand has two modes of chelation
with metal ion. The first mode is through two coordi-
tion. The biological activity of the tested ligands and
Table 5. Effect of HL, Phen, and their metal complexes with
5
000 ppm against migration of second-stage larvae
of root-knot nematode Meloidgyne javanica under
laboratory conditions
nated bonds with O of the terminal hydroxyl group
1
and O of the carbonyl group, but the second mode is
8
Compound
Percentage inhibition
through O of the terminal hydroxyl group and azo-
1
methine nitrogen N5, so two possible structures can be
obtained. Here we will investigate the two structures
and detect which is the more stable one. The octahedral
structure of the complex is completed by the coordina-
tion of the central metal ion with the water molecules.
The DFT calculations depend upon using the Gaussian
HL
Phen
7.5
7.8
85.6
57.7
0
72.9
76.1
27.0
(1)
(2)
(3)
(4)
(5)
(6)
9
8 W package of the programs. B3LYP is the keyword
for the hybrid functional. The higher basis set CEP-
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
9

Article
Zordok et al.
lengths are similar to those observed in related com-
61,62
plexes.
Also, the bond distances between two oxy-
gen atoms of the HL ligand O1 of the hydroxyl group
and O8 of the carbonyl group are 1.889 and
6
3,64
1
.802 Å.
The difference in the HL ligand distances
63,64
O8─C7 and O1─C2 (1.213 and 1.369 Å
) confirms
the formation of a bond between the oxygen atoms of
HL ligand and Co(II). The octahedral coordination
environment is completed by two oxygen atoms from
the two water molecules. The bond distances between
the central metal ion Co(II) and two oxygen atoms of
65
water molecules O13 and O14 are 1.845 and 1.846 Å.
Fig. 5. Optimized geometrical structure of the [Co
2
+
In the first Co(II) complex, there is a significant build-
up of charge density on the oxygen atoms (O1 of
hydroxyl group −0.270 and O8 of carbonyl group
(
HL)(Phen)(H O) ] complex in case of first
2 2
mode of chelation of HL ligand through the
oxygen atom of carbonyl group besides the
oxygen atom of the hydroxyl group by using
B3LYP/CEP-31G.
−
0.357). Also, there is more positive charge accumu-
lated on the central metal ion Co(II) (+0.131) as given
in Table S4.
3
1G was chosen to detect the energies at a highly accu-
rate level.
In the second mode of chelation of Co(II) with the
mixed ligand, as shown in Figure S5, the bond distances
between Co(II) and nitrogen atoms of phen N6 and N9
2+
Description of the structure of [Co(HL)(Phen)(H O) ]
2
2
61,62
Figure 5 shows the complex resulting from chela-
tion of Co(II) with mixed ligand in first mode, along
with the atomic numbering scheme. Selected bond dis-
tances and angles are given in Table S4. The
Co(II) atom is bonded with one molecule of Phen, and
the HL molecule is bonded with the central metal ion
through O1 of the hydroxyl group and O8 of the car-
bonyl group, and two water molecules.
are 1.808 and 1.823 Å,
which are shorter than that
in first mode of chelation. The axial plane is occupied
by O1 of the hydroxyl group of the HL molecule and
O10 of the water molecule. The angle O1─Co─O10 is
ꢀ
166.72 . This plane is perpendicular to the equatorial
plane, which is occupied by two nitrogen atoms of the
Phen ligand (N6 and N9), azomethine nitrogen N5 of
HL, and the fourth atom O11 of the second molecule
of water. The bond distance between Co(II) and the
azomethine nitrogen atom N5 of HL ligand is
The complex is in an irregular octahedral environ-
ment, as can be inferred from the values of bond angles
ꢀ
66
63
around the Co(II) ion, which varied from 79.30 to
1.851 Å and the bond distance Co─O1 is 1.838 Å.
ꢀ
1
72.04 . In the equatorial plane, the metal ion is coordi-
From the values of the bond angles given in Table S5,
the angles around Co(II) ion in this complex vary
nated by four atoms, namely two nitrogen atoms
N9 and N12) of Phen and two oxygen atoms (O8 of
ꢀ
(
between 81.43 and 175.19 , which agree with those of a
HL unit and O14 of water molecule). The axial plane is
occupied by two oxygen atoms O1 of the hydroxyl
group of HL and O13 of the water molecule. The bond
regular octahedral structure complex. Also, in the sec-
ond mode of chelation, the benzene ring of the HL
ligand is perpendicular to the molecule of Phen and not
parallel as in first mode of chelation. The charges on
the donating atoms of the mixed ligand O1, N5, N6,
and N9 are −0.238, −0.058, −0.145, and −0.163, and
the accumulated charge over N9 in second mode of che-
lation is less negative than O8 in first mode of chela-
tion. Also, the charge on O1 of the hydroxyl group in
the first mode is more negative than in the second
mode; moreover, Co(II) in the second mode of chela-
tion becomes much less positive with 0.008 less charge
ꢀ
angle O1─Co─O13 is equal to 158.24 , the two water
molecules lie cis to each other, and the angle
ꢀ
O14─Co─O13 is 82.18 , while the O8 of HL ligand lies
trans with respect to N12 of Phen ligand with the angle
ꢀ
1
66.52 . The benzene ring of the HL ligand occupies a
plane parallel to the plane of the Phen ligand, and the
ꢀ
dihedral angle C2─O1─M─N12 is 170.01 . The dis-
tances between Co(II) and nitrogen atoms of Phen
ligand N9 and N12 are 1.870 and 1.876 Å; these bond
1
0
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
7
0
than that in first mode. The large difference in charges
spreading over atoms between the two modes of chela-
tion plays an important role in detecting which is more
1.824 and 1.825 Å, while in the second mode they are
7
1
1.878 and 1.883 Å. In case of fist mode of chelation
of Cu(II) with HL through O8 of carbonyl group, the
bond distance Cu─O8 is 1.765 Å, while in the second
mode of chelation through the nitrogen atom N5 of the
azomethine group Cu–N5 is 1.866 Å.
6
7
72
stable and thus can be formed. So, the Co(II) ion
favors chelation with HL ligand through the O8 of car-
bonyl group besides O1 of hydroxyl group, and this
result can be supported from the values of the calcu-
lated energies and dipole moments given in Table S6.
The complex of the first mode has a more negative
energy of −316.921 au and a greater value of dipole
moment of 6.29 D, while in case of complex of the sec-
ond mode, the calculated energy is −316.673 au and
dipole moment is 5.09 D.
73
The charge on the copper ion in the case of second
mode of chelation is 0.124, while that in case of the first
mode it is 0.007. The charges over all donating oxygen
atoms and nitrogen atoms of the two mixed ligands
become more negative than that in case of the complex
in first mode of chelation, as given in Tables S4 and S5.
The large positive charge on the copper ion and the
large negative charges on the surrounding donating
atoms in complex of second mode increase the degree
of interaction between the copper ion and the surround-
ing nitrogen atoms and oxygen atoms, so the copper
ion favors interaction with the HL ligand through the
azomethine nitrogen atom N5 and not through O8 of
the carbonyl group. The value of calculated energy and
the dipole moment for the complex in case of second
mode is −339.13037 au and 7.711 D, respectively
(Table S6). The energy value is less than that in case of
first mode (−338.88002 au) and dipole moment value is
greater than that in first mode (5.967 D). From the
charges and the values of the calculated energy and
dipole moment, the copper metal favors reaction with
the mixed ligands Phen and HL, as seen in the second
mode with Phen through two nitrogen atoms (N6 and
N9), with HL through (N5 of azomethine group and
O1 of hydroxyl group), and the complete the octahedral
structure by bonding with two water molecules.
2+
Description of the structure of [Cu(HL)(Phen)(H O) ]
2
2
Tables S4 and S5 list selected interatomic dis-
tances and angles for the two modes of chelation of
Cu(II) ion with mixed ligands Phen and HL. The struc-
tures of the two complexes with the atomic numbering
scheme are shown in Figures S6 and S7. The structure
consists of cationic monomeric units of [Cu(HL)(Phen)
2+
(
H O) ] and acetate anions. In this complex, the Phen
2 2
and HL ligands are present as neutral. The complex is
six-coordinate, and the complex in the first mode is in a
distorted octahedron environment around the metal
ꢀ
center with angles around Cu(II) varying from 69.17
ꢀ
to 173.75 , while the complex in the second mode of
chelation is a regular octahedron with angles around
ꢀ
ꢀ
central metal ion of 78.85 –174.25 . Also, the four
angles around the central metal ion in the equatorial
plane, which is occupied by two oxygen atoms of water
molecules (O10 and O11), one oxygen atom O1 of
hydroxyl group of HL ligand, and one nitrogen atom
ꢀ
ꢀ
3+
N6 of Phen, vary from 85.51 to 96.20 . The axial plane
is occupied by two nitrogen atoms (N5 of HL ligand
Description of the structure of [Y(HL)(Phen)(H O) ]
Selected bond lengths and angles for the complex
in the two modes of chelation are listed in Tables S4
2
2
ꢀ
ꢀ
and N9 of Phen) with an angle equal 178.66 –180 ;
these values do not differ much from those expected for
a regular octahedron. The bond distances between
Cu(II) and O1 of hydroxyl group in complex in second
mode of chelation is 1.853 Å, while in first mode it is
3+
and S5. The species [Y(HL)(Phen)(H O) ] in second
2
2
mode of chelation is monomeric and shows the typical
geometry of a pseudo-regular octahedral structure. The
HL ligand is bound to the Y(III) ion through the O1 of
hydroxyl group and N5 of the azomethine group and
the two nitrogen atoms (N6 and N9) of Phen, besides
the two water molecules, to complete its octahedral
structure. The bond lengths around the Y(III) ion com-
plex of the second mode progressively increases. The
bond distances between Y(III) and the two nitrogen
68
1.89 Å.
Also the bond distances between the
Cu(II) and water molecules in the second mode
Cu─O10 and Cu─O11 are 1.851 and 1.853 Å, respec-
tively, while in the first mode the Cu─O13 and
Cu─O14 distances are 1.889 and 1.896 Å, respec-
69
tively. The bond distances between the central metal
74
ion and two nitrogen atoms of Phen in first mode are
atom of Phen (N6 and N9) are 2.305 and 2.306 Å.
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
11

Article
Zordok et al.
Also, the bond distances between Y(III) and the two
donating atoms of HL ligand (O1 of the hydroxyl
group and N5 of azomethine group) are 2.556 and
value of the complex in the case of second mode is
−287.25984 au, which is more negative, while the
energy of complex in case of the first mode is
−286.91697 au and the dipole moment is 9.319D, while
the dipole moment of complex in case of second mode
is 12.971D, which is greater. All these factors enhance
the bonding of HL ligand with Y(III) ion through the
N5 of the azomethine group and not through O8 of the
carbonyl group.
75,76
2.338 Å,
but in case of the Y(III) complex in the
first mode the Y–N9 and Y–N12 are 2.231 and
7
7
2
2
.228 Å. Also, the Y─O1 and Y─O8 distances are
7
5,78
.305 and 2.246 Å.
The bond distances between the
Y(III) ion and the two oxygen atoms O10 and O11 of
water molecules in case of second mode are 2.489 and
79
2
.511 Å, while in case of the complex in first mode,
8
0
2+
Y–O13 and Y–O14 are 2.296 and 2.287 Å. The HL
ligand is bound to the Y(III) center through the azo-
methine nitrogen and hydroxyl oxygen with the forma-
tion of a six-membered chelate ring having the nitrogen
atom N5 trans to the N9 of Phen. Y(III) ion is the cen-
ter of the equatorial plane defined by O10 and O11 of
two water molecules, N6 of Phen, and O1 of HL
ligand, while the N5 of HL ligand and N9 of Phen lie
in the axial plane (Figure S9). The angles around the
central metal ion in the complex of second mode vary
Description of the structure of [ZrO(HL)(Phen)(H O)]
2
The coordination of the HL ligand with Zr(IV) of
zirconium ion was carried out through the nitrogen
atom of azomethine group and oxygen atom of
hydroxyl group (Figure S11) and not the oxygen atom
of carbonyl group as shown in Figure S10. The ZrO
complex in the second mode results in the formation of
a six-membered chelating ring with the HL ligand. The
relevant interatomic distances and angles are given in
Tables S4 and S5. The coordination polyhedron is
described by one HL ligand coordinated as bidentate,
two donors atoms (one carbonyl oxygen and one azo-
methine nitrogen), Phen, and one coordinated water
molecule beside the sixth bond with the oxygen atom of
zirconium ion. The four angles involving adjacent equa-
torial atoms, namely O10–Zr–O11, O11–Zr–N6, O1–
ꢀ
ꢀ
from 71.44 to 166.32 , while in case of first mode com-
ꢀ
plex the angles around Y(III) ion vary from 68.52 to
59.68 . These values agree with the distorted octahe-
ꢀ
1
dral structure seen in Figure S8 and listed in Table S3.
The plane occupied by the HL ligand is perpendicular
to the plane of Phen, and the angle between O1 of the
hydroxyl group and two nitrogen atoms of Phen
ꢀ
ꢀ
ꢀ
Zr–N6, and O1–Zr–O10, are 87.83 , 89.89 , 95.34 ,
ꢀ
ꢀ
ꢀ
(
N6 and N9) are 83.45 and 76.79 , respectively, in the
and 86.82 , respectively. The bond angle between the
Y(III) complex of second mode, as reported in
Table S5. There is a significant build-up of charge den-
sity on the donating atoms N6, N9, N5, and O1 in case
of second mode of −0.145, −0.147, −0.424, and −0.269,
respectively. These values are more negative than in
first mode, and also the central metal ion in second
mode has a greater positive charge +0.644 as given in
Table S5. However, the charge accumulated in central
metal ion in case of first mode is +0.569, as listed in
Table S4. The large negative values of charge density
on the donating atoms and the large positive charge on
central metal ion in case of second mode reflect the
strong interaction between the Y(III) ion and the sur-
rounding nitrogen and oxygen atoms, so the Y(III) ion
favors interaction with the HL ligand through O1 of
the hydroxyl group and nitrogen atom N5 of azo-
methine group and not through O8 of carbonyl group.
This result can be confirmed from the calculated energy
and dipole moment values in Table S6. The energy
two axial atoms N5 of azomethine group of HL ligand
and N5 of Phen is 160.82 , whose value deviates
ꢀ
slightly from linearity. All these bond angles around the
Zr(IV) ion in the complex of second mode agree nicely
with the values of a regular octahedral structure. The
interatomic distances of the complex in case of the sec-
ond mode have been found to be Zr–N6 and Zr–N9
8
1,82
equal to 2.132 and 2.134 Å,
Zr–O1 and Zr–N5
83
84
2.104 Å and 2.131 Å, while the bond distances
between Zr(IV) ion and oxygen atoms O10 of water
molecule is 2.115 Å and oxygen atom of zirconium
85
86
ion O11 is 2.011 Å. The charges spreading over all
donating nitrogen and oxygen atoms in case of the
complex in the second mode have greater negative
values than in the first mode, as listed in Tables S4 and
S5. Also, the Zr(IV) ion in case of the second mode of
chelation possesses more positive charge of 0.462, while
in the case of the second mode the charge on the metal
ion Zr(IV) has a less positive value. The calculated
1
2
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
energy value and dipole moment for the complex in the
second mode of chelation as given in Table S6 are
−
286.86613 au and 14.518 D, respectively, while the
corresponding values for the first mode are −286.857 au
and 3.511 D. There is no large difference between the
two complexes, but there is large difference in the value
of dipole moment, which affects the degree of stability
of the complexes. Briefly, the HL ligand is bonded with
Zr(IV) through oxygen atom of the hydroxyl group and
nitrogen atom of azomethine group, which is attributed
to the calculated energies, dipole moments, and charges
on the metal ion and the surrounding donating atoms.
Fig. 6. TD-DFT-calculated electronic transitions in all
2+
studied complexes, [Co(HL)(Phen)(H O) ] , in
2
2
the case of the first mode of chelation of the HL
ligand and other three complexes [Cu(HL)
2
+
3+
(
[
Phen)(H O) ] , [Y(HL)(Phen)(H O) ] and
2 2 2 2
2+
Zro(HL)(Phen)(H O) ] in case of the second
EXCITED STATE
2 2
mode of chelation of HL ligand by using
B3LYP/LANL2DZ level.
Time-dependent density functional response the-
ory (TD-DFT) calculation at the B3LYP/LANL2DZ
level has been proved to give accurate description of the
8
7,88
UV–vis spectra.
TD-DFT has recently been refor-
and H – 4 ! L). The transitions in the case of Y(III)
and Zr(IV) are H ! L + 2, H – 2 ! L + 1, and H !
L, H – 2 ! L + 1 respectively. From the molecular
orbital analysis as given in Table S7 for the
Co(II) complex, there are five transitions (carried out
from HOMO and HOMO-2), which are localized on the
HL by 99% and 93.3% and HOMO-1, HOMO-4, and
HOMO-8, which are localized on Phen with 93.9%,
98.9%, and 100% to the lowest unoccupied molecular
orbitals (LUMO, LUMO + 1 and LUMO + 10), which
localized on Phen with 91.2, 100, and 98.1%, respec-
tively, and LUMO + 7, which is delocalized and spread
over all atoms especially Co(II) (20%) and Phen (62%).
For the Cu(II) complex, there are four electronic
transitions; most of these transitions were from HOMO
and HOMO-4, which are localized on Phen with 98.6
and 99.9%, and HOMO-1 and HOMO-2, which are
localized on HL (97.5 and 100%) to unoccupied MOs
LUMO and LUMO + 2, which localized on Phen (89.5
and 98.3%, respectively). In case of the Y(III) complex,
there are two transitions from HOMO and HOMO-2,
which are localized on HL with 98 and 99.1%, to
LUMO + 1 and LUMO + 2, which are localized on
the Y(III) ion with 83.2 and 78.4%. In the
Zr(IV) complex, there are two transitions from HOMO
and HOMO-2 to LUMO and LUMO + 1, which delo-
calized and spread over the complex.
89
mulated to compute discrete transition energies and
oscillator strengths and applied to a number of different
atoms and molecules. Bauernschmitt and Ahlrichs
8
9
90
included hybrid functionals in the calculation of excita-
tion energies. These hybrid methods typically are a
considerable improvement over the conventional
Hatree–Fock (HF)-based methods. In this work, several
excited states were calculated for each complex. The
type and energy of the excited states were also calcu-
lated. The calculated optimized geometry was used in
all subsequent calculations, and the wave functions of
SCF MOs were explicitly analyzed. The calculated
wave functions of the different MOs reflect and suggest
the fraction of the different fragments of the complex
contributing to the total wave functions of different
states. The results indicate the extent of electron delo-
calization in the different molecular orbitals.
All possible electronic transitions for all complexes
are shown in Figure 6 and listed in Table 6. All com-
plexes exhibit a theoretical LMCT band by using TD-
DFT at 386, 389, 351, and 412 nm for Co(II), Cu(II),
Y(III), and Zr(IV) complexes, respectively, which is typi-
cal of a distorted octahedral structure. These assign-
ments are supported nicely by experimental data. In
case of the Co(II) complex, this band results from six
transitions (H – 1 ! L + 1, H – 2 ! L, H – 4 ! L,
H – 5 ! L, H – 7 ! L + 7, and H – 8 ! L + 10) while
in the Cu(II) complex the band at 389 nm results from
four transitions (H ! L + 2, H – 1 ! L, H – 2 ! L,
Complexes of Co(II) and Cu(II) exhibit d–d tran-
sition bands at 559.35 and 561.95 nm, as shown by
TD-DFT calculations. For the Co(II) complex, the d–d
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
13

Article
Zordok et al.
Table 6. Computed excitation energies (eV), electronic transition configurations, and wavelengths (nm) of the obtained stable
2
+
2+
3+
2+
complexes [Co(HL)(Phen)(H O) ] , [Cu(HL)(Phen)(H O) ] , [Y(HL)(Phen)(H O) ] , [Zro(HL)(Phen)(H O) ] by
2
2
2
2
2
2
2
2
using B3LYP/Cep-31G for f ≥ 0.001 (f is the oscillator strength)
eV nm Major contributions
Complex
Co(II)
4.2801 289.67 H ! L + 2 (23%), H − 1 ! L + 1(25%), H − 5 ! L + 2(6%), H − 6 ! L + 1(11%)
3
.2103 386.20 H − 1 ! L + 1 (21%), H − 2 ! L (12%), H − 4 ! L (10%), H − 5 ! L (6%), H − 7 ! L + 7
(3%), H − 8 ! L + 10(5%)
2
.2165 559.35 H ! L + 11 (13%), H − 1 ! L + 10 (13%), H − 2 ! L + 9 (17%), H − 3 ! L + 8 (14%),
H − 4 ! L + 2 (6%)
Cu(II)
Y(III)
3.1793 389.98 H ! L + 2 (32%), H − 1 ! L (33%), H − 2 ! L (3%), H − 4 ! L (14%)
2
.2064 561.95 H − 1 ! L + 1 (18%), H − 2 ! L + 6 (17%), H − 3 ! L + 1 (6%)
3.5306 351.17 H ! L + 2 (36%), H − 2 ! L + 1 (10%)
4
.4824 276.6
.5598 271.91 H ! L (60%), H − 1 ! L (14%)
H ! L + 1 (50%), H − 2 ! L + 1(38%)
4
Zr(IV)
3.0061 412.44 H ! L (41%), H − 2 ! L + 1 (8%)
4
5
5
.8137 257.5
H − 8 ! L + 1 (54%)
.0715 244.47 H − 6 ! L (5%), H − 4 ! L (50%), H − 2 ! L (22%)
.3011 233.88 H ! L (18%), H − 1 ! L (39%)
transition band results from five electronic transitions
chloride heptahydrate), and UO (CH COO) .2H O
2 3 2 2
(
H ! L + 11,
H − 1 ! L − 10,
H − 2 ! L + 9,
(uranyl acetate dihydrate) were from Aldrich Chemical
Co. The organic compounds ethylcarbazate and 1,10
phenanthroline monohydrate were purchased from
Obour Pharmaceutical Industrial Company.
H − 3 ! L + 8, and H − 4 ! L + 2) as given in
Table 6 (572 nm in DMF solution), typical of a dis-
torted octahedral geometry. In the Cu(II) complex, the
d–d transition consists of three electronic transitions
(
H − 1 ! L + 1, H − 2 ! L + 6, and H − 3 ! L + 1
Physical measurements
[
574 nm in DMF]). These assignments agree with
The IR spectra of HL, phen, and its metal com-
plexes were recorded from KBr disks using an FTIR
experimental data, which confirms that the Co(II) ion
favors chelation with HL ligand through the oxygen
atom of carbonyl group besides the oxygen atom of the
hydroxyl group, whereas other metal ions Cu(II),
Y(III), and Zr(IV) are chelated with the HL ligand
through the oxygen atom of the hydroxyl group and
the nitrogen atom of the azomethine group.
1
460 plus instrument. H NMR spectra were recorded
on a Varian Mercury VX-300 NMR spectrometer using
DMSO-d as solvent. The elemental analysis for C, H,
6
and N was done using a Perkin Elmer CHN 2400 ana-
lyzer. The percentages of metal ions were determined
gravimetrically by transforming the solid products into
metal or metal oxide and also by using the atomic
absorption method. A spectrometer (model PYE-
UNICAM SP 1900) fitted with the corresponding lamp
was used for this purpose. The absorption spectra of
the ligands and the isolated solid complexes were
obtained in the region 200–800 nm using a UV-3101PC
Shimadzu instrument. TGA-DTG measurements were
EXPERIMENTAL
Materials
All chemicals used for the synthesis of compounds
were of the analytical reagent grade, commercially
available from different sources and used without fur-
ther purification. Salicylaldehyde, toluene, FeCl .6H O
carried out under N atmosphere from room tempera-
3
2
2
ꢀ
(ferric chloride hexahydrate), ZrOCl .8H O (zirconyl
ture up to 1000 C using the TGA-50H Shimadzu
2
2
chloride octahydrate) (99.9%), and AgNO3 (silver
nitrate) were purchased from Fluka chemical
Co. CoCl .6H O (cobalt chloride hexahydrate),
instrument, and the mass of the samples was accurately
weighted out in an aluminum crucible. Magnetic sus-
ceptibilities of the powdered samples were determined
on a Sherwood scientific magnetic balance using a
Gouy balance at room temperature using Hg[Co
2
2
Cu(CH COO)2 (copper acetate), YCl .6H O (yttrium
3
3
2
chloride hexahydrate), LaCl .7H O (lanthanum
3
2
1
4
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
(
(
CSN)4] as calibrant. The molar conductance
1 × 10 M solutions) of the ligands and metal com-
Complex (2)
−3
[Ethyl-2-(2-hydroxybenzylidine)-hydrazine-carbox-
ylate] 1,10-phenanthroline diaqua cupper acetate.
Complex (3)
[Ethyl-2-(2-hydroxybenzylidine)-hydrazine-carbox-
ylate] 1,10-phenanthroline diaqua yttrium chloride
octahydrate.
plexes in DMF was measured at room temperature
using a CONSORT K410 meter. All measurements
were carried out at ambient temperature with freshly
prepared solutions. Melting points were recorded on a
Buchi apparatus. Mass spectra were recorded on
GCMS-QP-1000EX Shimadzu (ESI-70ev) mass spec-
trometer in the range m/z 0–1090. XRD analyses were
carried out by using a Philips Analytical X-ray BV dif-
fractometer (type PW 1840). Radiation was provided
by a copper target (Cu anode 2000 W) in a high inten-
sity X-ray tube operated at 40 kV and 25 mA.
Complex (4)
[Ethyl-2-(2-hydroxybenzylidine)-hydrazine-carbox-
ylate] 1,10-phenanthroline aqua oxozirconium
chloride dihydrate.
Complex (5)
[Ethyl-2-(2-hydroxybenzylidine)-hydrazine-carbox-
ylate] 1,10-phenanthroline diaqua lanthanum chlo-
ride octahydrate.
Synthesis of ethyl 2-(2-hydroxy benzylidine)-hydrazine
carboxylate, Schiff base (C H N O ) HL
1
0
12
2
3
Complex (6)
The white precipitate of HL was synthesized by
the dropwise addition of an ethanolic solution of ethyl-
carbazate (1 mmol, 0.104 g) into a solution of salicylal-
dehyde (1 mmol, 0.122 mL) in ethanol. After
[
Ethyl-2-(2-hydroxybenzylidine)-hydrazine-carbox-
ylate] 1,10-phenanthroline aqua dioxo uranium
acetate.
completion of the addition, the solution was refluxed at
NEMATICIDAL INVESTIGATION
Culture technique
ꢀ
70 C in a round-bottomed flask equipped with a mag-
netic stirrer for 10 h. The resulting solution was concen-
Root-knot nematode (Meloidgyne javanica) was
propagated in pure culture in the Central Agricultural
Pesticides Laboratory. Individual egg-masses with their
mature females were removed from the galls of the
trated to 8 mL on a water bath and allowed to cool at
ꢀ
0
C. The white precipitate was filtered off, washed sev-
eral times by ethanol, and dried under vacuum over
CaCl (Yield: 84.5%).
91
2
infected roots. Each egg-mass was placed in a 10-mL
Synthesis of mixed ligand metal complexes
The dark
glass capsule containing distilled water. The female
under the particular egg-mass was removed from the
root tissue, dissected, and identified by microscope
examination of its perineal pattern system. Identifica-
tion was recorded according to the corresponding egg-
mass of previously identified females. The egg-mass was
singly put on the root system of 2-week-old tomato
seedling (race number CV) Pritchard in 15 cm clay pots
filled with steam-sterilized sandy loam soil. The inocu-
lated pots were watered thoroughly and kept in a green-
pink solid complex [Co(HL)(Phen)(H O) ]Cl .H O (1)
2
2
2
2
was prepared by adding 1 mmol (0.238 g) of cobalt
chloride hexahydrate in 30 mL absolute ethanol drop-
wise to a stirred suspended solution 1 mmol (0.208 g)
of HL and 1 mmol (0.198 g) of Phen in 30 mL ethanol.
The reaction mixture was boiled and stirred under
reflux for 12 h. The formed solid product was separated
by filtration, washed thoroughly with ethanol, and dried
under vacuum over anhydrous CaCl2.
ꢀ
The brown, pink, dark yellow, pink, and brown
house at 25 ꢂ 5 C. Two months after inoculation, the
[
Cu(HL)(Phen)(H O) ](CH COO) (2), [Y(HL)(Phen)
plants were removed from the pots and the root system
of each plant was examined for nematodes infection
and reproduction. Samples were taken from the infected
roots that contained adult females and egg-masses for
identification to confirm the nematode species to their
original patterns. The infected roots were used for inoc-
ulation of tomato seedlings CV. Pritchard growth in 25-
cm pots filled with a 3:1 mixture of sand and clay soil.
New tomato seedlings were transplanted to the pots as
2
2
3
2
(
(
(
H O) ]Cl .8H O (3), [ZrO(HL)(Phen)(H O)]Cl .2H O
2 2 3 2 2 2 2
4), [La(HL)(Phen)(H O) ]Cl .8H O (5), and [UO (HL)
2
2
3
2
2
phen)(H O)](CH COO) (6) were prepared in a similar
2
3
2
manner as above by using ethanol as solvent.
Complex (1)
[
Ethyl-2-(2-hydroxybenzylidine)-hydrazine-carbox-
ylate] 1,10-phenanthroline diaqua cobalt chloride
monohydrate.
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
15

Article
Zordok et al.
needed. By repeating this procedure, enough quantities
of the inocula from the pure culture were obtained.
U(VI) complexes, which indicated that carbonyl group
is free from complexation. But in the case of the
Co(II) complex, the shift of υ(C═O) to a higher wave
number indicates that coordination occurred through
the oxygen of the carbonyl group and phenolic oxygen.
Also in the Co(II) complex, the υ(C═N) remained
unchanged, indicating that the (C═N) group was free
from complexation, while in other complexes the shift
of υ(C═N) to lower or higher frequency indicated the
participation of the mixed ligand in coordination and
the formation of a bond between the nitrogen of HL
and nitrogen of Phen. Theoretical study confirmed the
experimental data by studying the excited states and
all possible electronic transitions.
Bioassay technique
Evaluation of tested ligands and their complexes
as nematicides were carried out according to migration
92
method. The bioassay unit consisted of a polyethylene
tube 1.3 cm long and 2.4 cm diameter, covered at one
end with two layers, the first one being a paper hand-
kerchief and second a muslin cloth. It was filled with
washed and air-dried sand of particle size 250 μm and
placed upright in a Petri dish (5 cm diameter). The
tested ligand and their complexes were prepared in eth-
anol with 5000 ppm concentration. One milliliter of the
tested concentration was pipetted on surface of sand in
ꢀ
Supporting information
Additional supporting information is available in
the online version of this article.
each tube and kept at 25 ꢂ 2 C to evaporate the sol-
vent. After 24 h, 1 mL of water was pipetted on surface
of sand in each tube, and then 1 mL of water contain-
ing the second-stage larvae of 100 M. javanica was
pipetted on the surface of the sand in each tube. Each
bioassay unit was transferred to a Petri dish (9 cm
diam.) containing a filter paper saturated with 2 mL
water to serve as humidity room to prevent evapora-
tion. After 24 h, the bioassay unit was taken out from
the humidity room and 8 mL distilled water was added
to the Petri dish of the bioassay unit. The number of
second-stage larvae that had migrated in the bioassay
dish was recorded 72 h later. The number of migrated
second-stage larvae in treatments was expressed as the
percentage of number in control, and each treatment
was replicated four times. The inhibition percentages
were calculated.
REFERENCES
1
2
3
4
. S. Yamada, Coord. Chem. 1999, 192, 537.
. S. Tong, L. Na, Chin. Chem. Lett. 1992, 3, 201.
. A. Sengul, Turk. J. Chem. 2004, 28, 703.
. F. Ledl, E. Schleicher, Angew. Chem. Int. Ed. Engl. 1990,
2
9, 565.
5. K. Singh, D. P. Singh, M. S. Barwa, P. Tyagi, Y. Mirza,
J. Enzyme Inhib. Med. Chem. 2006, 21, 557.
6
. S. Dayan, A. Cetin, N. Burcu Arslan, N. Kalaycıo ꢀg lu
Ozpozan, N. Ozdemir, O. Dayan, Polyhedron 2015,
8
5, 748.
7
8
9
. S. Dayan, N. Kalaycıo ꢀg lu Ozpozan, N. Ozdemir,
O. Dayan, J. Organomet. Chem. 2014, 21, 770.
. M. A. Akbar, M. H. Mirza, A. L. Tan, L. K. Wei,
P. V. Bernhardt, Polyhedron 2004, 23, 2037.
. J. Costamagna, J. Vargas, R. Latorre, A. Alvarado,
G. Mena, Coord. Chem. 1992, 119, 67.
CONCLUSIONS
1
0. A. S. Gaballa, C. Wanger, S. M. Teleb, E. Nour,
M. A. F. Elmosallamy, G. N. Kaluderovic, H. Schmidt,
D. Stembom, J. Mol. Struct. 2008, 876, 301.
From the investigation of metal complexes of
Co(II), Cu(II), Y(III), Zr(IV), La(III), and U(VI) with
mixed HL as the primary ligand and Phen as the second-
ary ligand (which acted as neutral bidentate ligands), the
complexes were formed in 1:1:1 ratio. The ligands had
1
1. V. T. Kasmov, S. Ozalp-Yaman, E. Tas, Spectrochim.
Acta A 2005, 62, 716.
12. Z. Almodares, S. J. Lucas, B. D. Crossley, A. M. Basri,
C. M. Pask, A. J. Hebden, R. M. Phillips,
P. C. McGowan, Inorg. Chem. 2014, 53, 727.
N O in the case of Cu(II), Y(III), Zr(IV), La(III), and
3
U(VI) or N O in the case of Co(II) complex cores
2
2
1
1
3. C. Zhang, C. Janiak, J. Chem. Crystallogr. 2001, 31, 29.
4. K. L. P. Sheeja Lovely, M. Christudhas, J. Chem. Pharm.
Res. 2013, 5, 154.
(nitrogen of azomethine, phenolic O atom of HL, and
two azomethine nitrogen atoms in Phen or two azo-
methine nitrogen atoms in Phen, phenolic O atom and
keto O atom in HL ligand). This result was confirmed
by the spectrum of HL assigned for υ(C═O), which
appeared in case of Cu(II), Y(III), Zr(IV), La(III), and
1
5. P. G. Sammes, G. Yahioglu, Chem. Soc. Rev. 1994,
2
3, 327.
16. H. Keypour, H. Goudarziafshar, A. K. Brisdon,
R. G. Pritchard, Inorg. Chim. Acta 2007, 360, 2298.
1
6
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017

JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Synthesis of New Metal Complexes
1
7. J.
Reedijk,
G.
Wilkinson,
R.
D.
Dillard,
35. S. A. Patil, V. H. Naik, A. D. Kulkarni, P. S. Badami,
Spectrochim. Acta A 2010, 75, 347.
36. Y. Najajreh, J. M. Perez, C. Navarro-Ranninger,
D. Gibson, J. Med. Chem. 2002, 45, 5189.
37. P. A. Nguewa, M. A. Fuertes, S. Iborra, Y. Najajeh,
D. Gibson, E. Matínez, C. Alonso, J. M. Pérez, J. Inorg.
Biochem. 2005, 99, 727.
38. L. H. Jones, Spectrochim. Acta A 1959, 15, 409.
39. S. P. Mcglynn, J. K. Smith, W. C. Neely, J. Chem. Phys.
1961, 35, 105.
J. A. McCleverty, Comprehensive Coordination Chemistry,
Eds., Pergamon, Oxford 1987, 2, 73.
8. Y. Shen, B. P. Sullivan, Inorg. Chem. 1995, 34, 6235.
9. S. Kumar, D. N. Dhar, P. N. Saxena, J. Sci. Ind. Res.
1
1
2
009, 68, 181.
0. H. Ebrahimi, J. S. Hadi, H. S. Al-Ansari, J. Mol. Struct.
013, 37, 1039.
1. A. K. Shaikh, K. Shaikh, Can. Chem. Trans. 2015,
, 207.
2
2
2
3
2
2
2. D. J. Chitwood, Annu. Rev. Phytopathol. 2002, 40, 221.
3. R. A. Sikora, E. Fernandez, Plant Parasitic Nematodes in
Subtropical and Tropical Agriculture, CABI Bioscience,
Egham, UK, 2005, p. 319.
40. S. Khaled, K. A. Shaikh, Z. A. Mohammed, Chem. Sci.
Trans. 2013, 2, 591.
41. S. Khaled, Z. A. Mohammed, G. K. Firdous,
K. A. Shaikh, Int. J. Inorg. Chem. 2013, 2013, 212435.
42. P. Roy, M. Manassero, Dalton Trans. 2010, 39, 1539.
43. L. N. Sharada, M. C. Ganorkar, Indian J. Chem. 1988,
27, 617.
44. S. K. Dutta, S. B. Kumar, S. Bhattacharyya,
E. R. T. Tiekink, M. Chaudhury, Inorg. Chem. 1997,
36, 4954.
45. I. Turel, P. Bukovec, M. Quirós, Int. J. Pharm. 1997,
152, 59.
46. A. B. P. Lever, Coord. Chem. Rev. 1968, 3, 119.
47. N. Mondal, D. K. Dey, S. Mitra, K. M. Abdul Malik,
Polyhedron 2000, 19, 2707.
48. S. A. Sadeek, M. S. El-Attar, S. M. Abd El-Hamid, Bull.
Chem. Soc. Ethiop. 2015, 29, 1.
49. T. Skauge, I. Turel, E. Sletten, Inorg. Chim. Acta 2002,
339, 247.
50. B. Macias, M. Martinez, A. Sanchez, A. Dominguez, Int.
J. Pharm. 1994, 106, 229.
51. B. Macias, M. V. Villa, I. Rubio, A. Castineiras,
J. Borras, J. Inorg. Biochem. 2001, 84, 163.
52. A. L. Ringer, C. D. Sherrill, R. A. King, T. D. Crawford,
Int. J. Quantum. Chem. 2008, 108, 1137.
2
4. Gaussian 98, Revision A.6, M. J. Frisch, G. W. Trucks,
H. B. Schlegel, G. E. Scuseria, M. A. Robb,
J. R. Cheeseman, V. G. Zakrzewski, J. A. Montgomery,
J. R. E. Stratmann, J. C. Burant, S. Dapprich,
J. M. Millam, A. D. Daniels, K. N. Kudin, M. C. Strain,
O. Farkas, J. Tomasi, V. Barone, M. Cossi, R. Cammi,
B. Mennucci, C. Pomelli, C. Adamo, S. Clifford,
J. Ochterski, G. A. Petersson, P. Y. Ayala, Q. Cui,
K. Morokuma, D. K. Malick, A. D. Rabuck,
K. Raghavachari, J. B. Foresman, J. Cioslowski,
J. V. Ortiz, B. B. Stefanov, G. Liu, A. Liashenko,
P. Piskorz, I. Komaromi, R. Gomperts, R. L. Martin,
D. J. Fox, T. Keith, M. A. Al-Laham, C. Y. Peng,
A. Nanayakkara, C. Gonzalez, M. Challacombe,
P. M. W. Gill, B. Johnson, W. Chen, M. W. Wong,
J. L. Andres, C. Gonzalez, M. Head-Gordon,
E. S. Replogle, J. A. Pople, Gaussian, Inc., Pittsburgh,
PA, 1998.
2
2
5. W. Kohn, L. J. Sham, Phys. Rev. A 1965, 140, 1133.
6. N. J. Garrido, L. Perello, R. Ortiz, G. Alzuet,
M. G. Alvarez, E. Canton, M. L. Gonzalez,
S. G. Granda, M. P. Priede, J. Inorg. Biochem. 2005,
53. B. S. Manhas, A. K. Trikna, J. Indian Chem. Soc. 1983,
59, 315.
9
9, 677.
2
2
7. F. Karipcin, E. Kabalcilar, Acta Chim. Slov. 2007, 54, 7.
8. P. R. Reddy, S. Rajeshwar, B. Satyanarayana,
J. Photochem. Photobiol. B: Biol. 2016, 160, 217.
9. W. A. Zordok, W. H. El-Shwiniy, M. S. El-Attar,
S. A. Sadeek, J. Mol. Struct. 2013, 1047, 267.
0. N. Raman, R. Mahalakshmi, L. Mitu, Spectrochim. Acta
A 2014, 131, 355.
1. R. S. Kumar, S. Arunachalam, Polyhedron 2007,
54. A. W. Coats, J. P. Redfern, Nature 1964, 201, 68.
55. H. H. Horowitz, G. Metzger, Anal. Chem. 1963, 35, 1464.
56. A. A. Frost, R. G. Pearson, Kinetics and Mechanism,
Wiley, New York, 1961.
57. S. A. Sadeek, W. H. EL-Shwiniy, J. Mol. Struct. 2010,
981, 130.
2
3
3
3
58. Q. Zhao, Y. Shen, M. Ji, L. Zhang, T. Jiang, C. Li,
J. Ind. Eng. Chem. 2014, 20, 544.
2
6, 3255.
2. A. A. Schilt, R. C. Taylor, J. Inorg. Nucl. Chem. 1959,
, 211.
59. J. N. Sasser, C. C. Carter, An Advanced Treatise on
Meloidogyne, Biology and Control, Vol. 1, North Carolina
State University Graphics, U.S.A. 1985, p. 422.
60. P. Kavitha, M. R. Chary, B. V. V. A. Singavarapu,
K. L. Reddy, J. Saudi Chem. Soc. 2016, 20, 69.
61. T. R. Todorovi ꢁc , A. Bacchi, D. M. Sladi ꢁc ,
N. M. Todorovi ꢁc , T. T. Boži ꢁc , D. D. Radanovi ꢁc ,
9
3
3
3. G. J. Kharadi, J. Therm. Anal. Calorim. 2012, 107, 651.
4. M. A. Diab, A. Z. El-Sonbati, A. A. El-Bindarya,
S. M. Morgan, M. K. Abd El-Kader, J. Mol. Liq. 2016,
2
18, 571.
J. Chin. Chem. Soc. 2017
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
17

Article
Zordok et al.
N. R. Filipovi ꢁc , G. Pelizzi, K. K. Andelkovi ꢁc , Inorg.
Chim. Acta 2009, 362, 3813.
75. D. Parkers, J. A. Williams, J. Chem. Soc. Dalton Trans.
1996, 0, 3613.
6
6
6
2. A. Bailey, W. P. Griffith, D. W. C. Leung,
76. L. M. Vallarino, J. Less Common. Met. 1989, 149, 121.
77. (a) R. Wang, Z. Zheng, T. Jin, R. J. Staples, Angew.
Chem. Int. Ed. 1999, 38, 1813. (b) R. Wang, H. Liu,
M. D. Carducci, T. Jin, C. Zheng, Z. Zheng, Inorg.
Chem. 2001, 40, 2743.
A. J. P. White, D. J. Williams, Polyhedron 2004,
2
3, 2631.
3. C. Chulvi, M. C. Munõz, L. Perelló, R. Ortiz,
M. I. Arriortua, J. Via, K. Urtiaga, J. M. Amigó,
L. E. Ochando, J. Inorg. Biochem. 1991, 42, 133.
78. J. Fischer, L. Ricard, R. Weiss, J. Am. Chem. Soc. 1976,
98, 3050.
4. N. Jiménez-Garrido, L. Perelló, R. Ortiz, G. Alzuet,
ꢁ
79. P. C. Andrews, T. Beck, B. H. Fraser, P. C. Junk,
M. Massi, Polyhedron 2007, 26, 5406.
M. González-Alvarez, E. Cantón, M. Liu-González,
S. García-Granda, M. Pérez-Priede, J. Inorg. Biochem.
8
8
0. Z. Zheng, Chem. Commun. 2001, 24, 2521.
2
005, 99, 677.
1. G. Paolucci, J. Zanon, V. Lucchini, W. E. Damrau,
E. Siebel, R. D. Fischer, Organometallics 2002, 21, 1088.
2. H. Brand, J. Arnold, Organometallics 1993, 12, 3655.
3. G. Paolucci, G. Pojana, J. Zanon, V. Lucchini,
E. Avtomonov, Organometallics 1997, 16, 5312.
6
6
5. A. Garoufis, S. Kasselouri, C. P. Raptopoulou, Inorg.
Chem. Commun. 2000, 3, 251.
6. L. E. Nikolaeva, A. A. Shevyrev, T. N. Tarkhova,
N. V. Belov, Kristallografiya 1974, 19, 516.
7. A. M. Mansour, Inorg. Chim. Acta 2013, 408, 186.
8. A. D. Garnovski, A. P. Sadimenko, M. C. Sadimenko,
D. A. Garnovski, Coord. Chem. Rev. 1998, 173, 31.
9. R. H. Holm, E. I. Solomon, Chem. Rev. 1996, 96, 2237.
0. M. Schmitz, S. Leininger, J. Fan, A. M. Arif, P. J. Stang,
Organometallics 1999, 18, 4817.
1. T. H. Noh, J. H. Kim, Y. A. Lee, H. Suh, O. S. Jung,
J. Mol. Struct. 2004, 691, 165.
2. E. R. Acunã-Cueva, R. Faure, N. A. Illán-Cabeza,
S. B. Jiménez-Pulido, M. N. Moreno-Carretero,
M. Quirós-Olozábal, Inorg. Chim. Acta 2003, 351, 356.
3. P. Chaudhuri, K. Wieghardt, Prog. Inorg. Chem. 2001,
8
8
6
6
8
8
8
8
8
8
4. H. Brand, J. A. Caprioni, J. Arnold, Organometallics
1
994, 13, 4469.
5. G. Paolucci, M. Vignola, L. Coletto, B. Pitteri,
F. Benetollo, J. Organomet. Chem. 2003, 687, 161.
6. I. Turel, L. Golic, P. Bukovec, M. Gubina, J. Inorg. Bio-
chem. 1998, 7, 153.
6
7
7
7. I. Ciofini, P. P. Laine, F. Bedioui, C. Admo, J. Am.
Chem. Soc. 2004, 126, 10763.
8. I. Ciofini, C. Daul, C. J. Adamo, J. Phys. Chem. A 2003,
7
1
07, 11182.
9. F. M. Casida, In Recent Advances in Density Functional
Methods, Part 1, D. P. Chong Ed., World Scientific, Sin-
gapore, 1995.
7
7
5
0, 151.
4. (a) D. Ang, G. B. Deacon, P. C. Junk, D. R. Turner,
Polyhedron 2007, 26, 385. (b)T. Fiedler, M. Hilder,
P. C. Junk, U. H. Kynast, M. M. Lezhnina,
M. Warzala, Eur. J. Inorg. Chem. 2007, 2, 291.
9
9
9
0. R. Bauernschmitt, R. Ahlrichs, Chem. Phys. Lett. 1996,
2
56, 454.
1. H. S. Ibrahim, S. E. S. Hamouda, A. M. A. El-kady,
H. I. Abd-Alla, Nat. Sci. 2014, 12, 40.
2. J. R. Anacona, C. Toledo, Transit. Met. Chem. 2001,
(
c) H. Bußkamp, G. B. Deacon, M. Hilder, P. C. Junk,
U. H. Kynast, W. Lee, D. R. Turner, CrystEngCommun
2
6, 228.
2
007, 9, 394.
1
8
www.jccs.wiley-vch.de
© 2017 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
J. Chin. Chem. Soc. 2017