Synthesis, crystal structure, chromatographic seperation, and thermogravimetric investigation of a ONNO type asymmetric Schiff base and its trinuclear complexes

Article abstract of DOI:10.1134/S1070328414080089

1,3-Propanediamine was put to react with 2-hydroxybenzaldehyde and 2-hydroxyacetophenone sequentially in aprotic medium. The crystalline product was examined by high performance liquid chromatography. The composition was 66% asymmetric Schiff base N(2-hydroxybenzylidene)-N'(2-hydroxyacetophenone)-1,3- propanediamine (SALLACH₂) and 33% bis-N,N'(2-hydroxyacetophenylidene) -1,3-propanediamine (LACH2). As the crystals were uniform and of appropriate size, the molecular model of the material was revealed by X-ray diffraction. It was seen that two molecules of SALLACH₂ and one molecule of LACH ₂ formed the mixed crystals. The substance was separated to its components and the asymmetric Schiff base was purified with a silica column. The substance was characterized with elemental analysis, FT-IR, MS, ¹HNMR, and ¹³C NMR. In addition, six tri-nuclear complex with the nuclear structure of Ni^II-Ni^II-Ni^II, Ni^II-Cu^II-Ni^II, Ni^II-Mn ^II-Ni^II were prepared from this Schiff base and stoichiometry was determined by elemental analysis, FT-IR and thermogravimetry. Finally, the molecular structures of two complexes were brought to light by XRD which highlights the asymmetry of the ligand more clearly.

Full text of DOI:10.1134/S1070328414080089

ISSN 1070ꢀ3284, Russian Journal of Coordination Chemistry, 2014, Vol. 40, No. 8, pp. 571–582. © Pleiades Publishing, Ltd., 2014.
Synthesis, Crystal Structure, Chromatographic Seperation,
and Thermogravimetric Investigation of a ONNO Type Asymmetric
Schiff Base and Its Trinuclear Complexes1
·
S. Öza, *, Ü. Ergunb, M. Yakutc, I. Svobodad, A. Atakolc, E. Kübra
I
nalc, N.
Yι
lmazc, and O. Atakolc
a Ahi Evran University, Faculty of Science and Arts, Department of Chemistry,
ehir, 40100 Turkey
b D
zce University, Faculty of Science and Arts, Department of Chemistry, Düzce, 81620 Turkey
K
ι
¸
rs
ü
c Ankara University, Faculty of Science, Department of Chemistry, Ankara, 06100 Turkey
d Strukturforschung, FB Materialwissenschaft, TUꢀDarmstadt, Petersenstrasse 23, Dꢀ64287 Darmstadt, Germany
*eꢀmail: drsevioz@gmail.com; soz@ahievran.edu.tr
Received November 22, 2013
Abstract
sequentially in aprotic medium. The crystalline product was examined by high performance liquid chromatogꢀ
raphy. The composition was 66% asymmetric Schiff base (2ꢀhydroxybenzylidene)ꢀ '(2ꢀhydroxyacetopheꢀ
none)ꢀ1,3ꢀpropanediamine (SALLACH2) and 33% bisꢀ (2ꢀhydroxyacetophenylidene)ꢀ1,3ꢀpropanediꢀ
—1,3ꢀPropanediamine was put to react with 2ꢀhydroxybenzaldehyde and 2ꢀhydroxyacetophenone
N
N
N,N'
amine (LACH2). As the crystals were uniform and of appropriate size, the molecular model of the material was
revealed by Xꢀray diffraction. It was seen that two molecules of SALLACH2 and one molecule of LACH2
formed the mixed crystals. The substance was separated to its components and the asymmetric Schiff base
was purified with a silica column. The substance was characterized with elemental analysis, FTꢀIR, MS,
1H NMR, and 13C NMR. In addition, six triꢀnuclear complex with the nuclear structure of NiII–NiII–NiII,
NiII–CuII–NiII, NiII–MnII–NiII were prepared from this Schiff base and stoichiometry was determined by
elemental analysis, FTꢀIR and thermogravimetry. Finally, the molecular structures of two complexes were
brought to light by XRD which highlights the asymmetry of the ligand more clearly.
DOI: 10.1134/S1070328414080089
1
INTRODUCTION
without preferably preparing the asymmetric Schiff
base, the aldehyde and amine components were put to
react in the presence of the metal ion of interest.
The Schiff bases that were made up of diamines and
aldehydes have been in the literature of coordination
chemistry since 1930s [1–6]. The mentioned Schiff
bases have symmetric structures established by sinꢀ
gle type aldehyde components. Among those, bisꢀ
N
and bisꢀ (2ꢀhydroxyphenylidene)ꢀ1,3ꢀpropanediꢀ
amine (LH2) hold an important place as tetradentate
ONNO type ligands. Especially, LH2 and its derivatives,
that form polyꢀnuclear complexes with interesting strucꢀ
tures, are often noticed [7–13].
The first complex that involves an asymmetric
Schiff base was reported in 1973 [21]. However, deꢀ
spite the fact that the name “asymmetric Schiff base”
and the idea beyond it have been long known, there
has not been any report on the synthesis and characꢀ
terization of such a substance. This study has been deꢀ
signed to fill this gap.
,
N
'
(2ꢀhydroxyphenylidene)ꢀ1,2ꢀdiaminoethane
N,N'
The Schiff base made up of 1,3ꢀpropanediamine
and 2ꢀhydroxybenzaldehyde has a tendency to form
polynuclear complexes of bisꢀ
N,N'(2ꢀhydroxypheꢀ
nylidene)ꢀ1,3ꢀpropanediamine (LACH2). Despite the
resemblance, a polyꢀnuclear complex involving bisꢀ
N,N'(2ꢀhydroxyacetophenylidene)ꢀ1,3ꢀpropanediꢀ
amine was absent in the literature. In this context, an
asymmetric Schiff base of 1,3ꢀpropanediamine with
one amino group condensed with 2ꢀhydroxybenzaldeꢀ
hyde and the other amino group with 2ꢀhydroxyaceꢀ
tophenone (SALLACH2) was designed. Sketch for
preparation of asymmetrical Schiff base SALLACH2:
On the other hand, studies involving asymmetric
Schiff bases prepared from diamines are not too much
seen. The studies on the asymmetrical ONNO type
Schiff bases have increased in recent years in literature
[14–20]. In these studies, Schiff bases are prepared
from symmetrical diamine and different two aldehyde
compounds or an asymmetrical diamine and an aldeꢀ
hyde compound.
Generally, the template synthesis method was emꢀ
ployed in the preparation of these complexes and
1
The article is published in the original.
571

572
ÖZ et al.
Step 1
H3C
NH2
C N
OH
H3C
C O
OH
Expected monocondensed Schiff base
+
–5
in MeCN
1 h –H O
…
0
°
C
+
NH2
H2N
2
CH3
H3C
N C
HO
N
C
OH
Step 2
LACH2
H
H3C
H3C
H3C
N C
HO
N
NH2
C N
OH
C
C O
OH
20
in MeCN
–H O
°
C
+
2
OH
SALLACH2
To this end, the molar equivalent carbonyl compoꢀ clear complexes were prepared from asymmetrical
nent was put to react with one mole of amine in aprotic Schiff base. The complex structure also contains aceꢀ
−
medium and under cold conditions. After a certain
tate (AcO–) or nitrite
The formulas of the complexes are given below.
anions as
μ
bridges [22].
(NO2 )
time, the other aldehyde component was added to the
mixture. It was clear that the obtained product was goꢀ
ing to be a mixture. Therefore, every solid substance
obtained by this method was analyzed by high perforꢀ
If NiSALLAC is described as the complex beꢀ
tween Ni2+ ion and SALLACH2 Schiff base, forꢀ
mance liquid chromatography (HPLC). Because that mulas of six trinuclear complexes are as follows:
the mixture contained symmetric Schiff bases, they {(NiSALLAC)Ni(AcO)2(DMF)2} (
I
);
{(NiSALLAC)2 Cu(AcO)2(DMF)2} (II);
(NiSALLAC)2Mn(AcO)2 (DMF)2} (III);
{(NiSALLAC)2Ni(NO2)2(DMF)2} (IV);
were also prepared accordingly to be used as HPLC
standards. It is very likely that the symmetric Schiff
bases are thermodynamically more stable than their
asymmetric counterparts since during the synthesis
when two of the carbonyl components were added
jointly onto the amine component, asymmetric Schiff
base formation was not observed. On the other hand, if
metal ions are present in the environment, there are
studies attesting the asymmetric Schiff base complex
formation [15–18].
{(NiSALLAC)2Cu(NO2)2(DMF)2} (V);
{(NiSALLAC)2Mn(NO2)2(DMF)2} (VI).
EXPERIMENTAL
Materials and apparatus. Used reactives were of
Merck or Fluka brands and they were used without
further purification. In this study, Shimadzu Infinity
FTIRꢀSpectrometer equipped with three reflectional
ATR unit was used for IR spectra. The C, H, and N
analyses were performed on Elemantar Vario Micro
Cube instrument. Metal analyses were recorded on
GBC Avanta PM Model atomic absorption spectromꢀ
eter using FAAS mode. Complex (2–3 mg) was disꢀ
solved in 1 mL HNO3 (63%) with heating, diluted to
100 mL and given to nebulizer of atomic absorpion
spectroscopy (AAS) for metal analysis. The mass specꢀ
tra were obtained by Shimadzu, 2010 plus with direct
inlet (DI) unit with an electron impact ionizer. DI
In this study the asymmetric Schiff base of 1,3ꢀproꢀ
panediamine with one amino group condensed with
2ꢀhydroxybenzaldehyde and the other amino group
with 2ꢀhydroxyacetophenone was successfully syntheꢀ
sized and isolated SALLACH2. The product was a
crystalline solid. It was analyzed by Xꢀray diffraction
methods and the molecular structure was determined.
Later on, the mixture was purified by column chromaꢀ
tography and the asymmetric Schiff base was isolated.
The elemental analysis and characterization study
were done by means of FTꢀIR, 1H NMR, 13C NMR,
MS and DSC. The abbreviation SALLACH2 will be
used for the isolated Schiff base from now on.
temperature was varied between 40–140°C and ionꢀ
ization was done with electrons with 70 eV energy. The
NMR spectra were recorded on the Bruker Ultrashield
300 MHz NMR spectrometer. DMSOꢀd6 solution was
The transformation of the isolated Schiff base to its
symmetric counterparts by hydrolization in amꢀ
phiprotic solvents was observed. In addition, six trinuꢀ
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

SYNTHESIS, CRYSTAL STRUCTURE, CHROMATOGRAPHIC SEPERATION
573
the solvent. The thermogravimetric analyses were perꢀ
formed by Shimadzu DTGꢀ60H. In thermogravimetꢀ
ric analyses, temperature was varied between 30–
600 C. These analyses were performed at 10 C/min
rate and under N2 atmosphere in Pt pans. Calibration
of the instrument was done with metallic In, Pb or Zn.
1000000
800000
600000
400000
200000
0
2
3
°
°
1
Synthesis of N(2ꢀhydroxybenzylidene)ꢀN'(2ꢀhydroxyꢀ
acetophenone)ꢀ1,3ꢀpropanediamine (SALLACH2). The
asymmetric Schiff base was prepared in MeCN that
was dehydrated by CaH2. 1,3ꢀDiaminopropane (3.7 g,
0.05 mol) was dissolved in 50 mL MeCN and the
temperature was decreased to –10°C in a saltꢀice
bath. 2ꢀHydroxyacetophenone (6.80 g, 0.05 mol) was
added with constantly stirring for 5 min. This solution
was kept in iceꢀwater mixture for half an hour and the
0
1
2
3
4
Time, min
5
6
7
8
temperature was kept under 1°C. After the duration,
Fig. 1. Obtained chromatograms for the mixture of Schiff
bases: symmetric LH , symmetric LACH and
salycilaldehyde (2ꢀhydroxybenzaldehyde) (6.10 g,
0.05 mol) was added to the solution and again the soꢀ
lution was kept in iceꢀwater mixture for half an hour,
stirring. After that, this solution was kept in the deep
2
2
2SALLACH
· LACH with 85% MeCN : 15% H O moꢀ
2 2 2
bile phase: LH (1), LACH (2), 2SALLACH · LACH (3).
2
2 2 2
freeze at –20
stance was obtained and filtered by vacuum. The filꢀ
trate was rinsed with MeCN and Et2O and airꢀdried.
The yield was 72–75%, m.p. = 88–89 C.
°C for 12 h. A yellow crystalline subꢀ
7.62 d., 7.45 d., 7.31 p., 6.88 t., 6.77 t., 3.73 t., 3.66 t.
2.40 s., 2.06 p.; 13C NMR (CH3SOCH3ꢀd6;
, ppm):
167.70, 164.32, 161.13, 132.86, 132.74, 132.09,
129.21, 119.31, 119.11, 118.97, 118.95, 118.62,
117.13, 117.08, 116.91, 56.46, 46, 33, 14.80 . The yield
δ
°
This crystalline substance was chromatographically
investigated. In chromatographic studies, the concenꢀ
tration of the asymmetric Schiff base within the mixꢀ
ture was determined by using symmetric Schiff bases
(LH2 and LACH2) as HPLC standards. The mobile
phase was selected as 85% MeCN : 15% H2O in which
the resolution was at its maximum. The chromatoꢀ
grams obtained by using 100 ppm stock LH2, LACH2
and SALLACH2 can be seen in Fig. 1.
was 36–40%, m.p. = 92–93°C.
All complexes were prepared by template synthesis.
The reaction of the Schiff base (SALLACH2) and
Ni(II) salt was carried out in one step in DMF and in
−
the presence of AcO– or
ions.
NO2
Synthesis of complexes containing acetate. 0.296 g
(0.001 mol) SALLACH2 was dissolved in 40.0 mL
A silica column (Merck silica gel 60, 40–63 μm)
with 50 cm height and 2.0 cm diameter was used to DMF by heating. The temperature was raised up to 95
separate the mixture. 50% EtAcO : 50% ꢀC6H14 was
n
to 110
of 0.237 g (0.001 mol) NiCl2
MeOH : DMF (50/50, v/v) and the solution of
0.0005 mol related Ni(II), Cu(II) or Mn(II) acetate
in 10 mL MeOH : DMF (50/50, v/v), 0.250 g
°
C. To this solution, added were the solution
6H2O salt in 10 mL
selected as the most suitable solvent for separation. It
was observed that LACH2 moved rapidly within this
solvent. In addition, the ratio of the Rf value of LACH2
and Rf value of SALLACH2 was approximately two.
Both substances being yellow, their locations in the
column were noted easily and the eluates were collectꢀ
ed. The compounds were obtained separately by evapꢀ
orating the solvent. SALLACH2 was recrystallized in a
little volume of MeCN and its purity was checked by
HPLC.
·
Ni(AcO)2
and 0.246 g Mn(AcO)2
·
4H2O for
I
, 0.201 g Cu(AcO)2
·
· H2O for II
4H2O for III. The final mixꢀ
ture was allowed left to stand for 4–5 days. The formed
crystalline complex was separated by vacuum filtration
and air dried.
{(NiSALLAC)2Ni(AcO)2(DMF)2} (
anal. calcd., %: C, 53.65; H, 5.87; N, 8.15; Ni, 17.10.
Found, %: C, 53.04; H, 5.7; N, 7.57; Ni, 18.35.
I)
C18H20N2O2 (SALLACH2)
anal. calcd., %: C, 72.94;
Found, %: C, 73.34;
H, 6.80;
H, 6.55;
N, 9.44.
N, 9.86.
IR (
(C–HAliph), 1651
1604 (C=N), 1583
(C–HAr). λmax = 348 nm,
DMSO.
ν
, cm–1): 3022–3049
(C=ODMF), 1633
(C=Cring), 1193 (C–OPhenol), 752
= 16457 dm3 mol–1 cm–1 in
ν
(C–HAr), 2920–2848
(C=OAcetate),
IR (
(C–HAliph), 1631–1624
1278–1159 (C–OPhenol), 752
= 8164 dm3 mol–1 cm–1 in DMSO. H NMR
(CH3SOCH3ꢀd6; , ppm): 16.55 s., 13.47 s., 8.58 s.,
ν
, cm–1): 3010–3023
(C=N), 1610
(C–HAr). λmax = 242 nm,
ν
(C–HAr), 2941–2854
ν
ν
ν
ν
ν
ν
(C=Cring),
ν
ν
ν
ν
δ
1
δ
ε
ε
δ
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

574
ÖZ et al.
Thermoanalytical data (TG): between 157 and 185
(DMF lost) theoretical mass loss 14.17%; found
14.02 0.95%.
°
C
TG: between 197 and 253°C (DMF lost) theoretical
mass loss 14.56%; found 15.17 1.33%.
{(NiSALLAC)2Cu(NO2)2(DMF)2} (V)
{(NiSALLAC)2Cu(AcO)2(DMF)2} (II
anal. C, 53.40; H, 5.84; N, 8.12; Ni,11.34; Cu, 6.14.
calcd., %:
Found, %: C, 53.91; H, 6.12; N, 7.91; Ni, 11.38;Cu, 6.42.
)
anal.
calcd., %:
C, 50.06; H, 5.00; N, 11.11; Ni, 11.65; Cu, 6.31.
Found, %: C, 49.87; H, 5.21; N, 10.77; Ni, 12.05; Cu, 6.65.
IR (
(C–HAliph), 1652
1598 (C=N), 1580
(C–OPhenol), 752
96824 dm3 mol–1 cm–1 in DMSO.
TG: between 191 and 258 C (DMF lost) theoretical
mass loss 14.49%; found 15.24 0.85%.
ν
, cm–1): 3013–3051
(C=ODMF), 1636
(C=Cring), 1315
(C–HAr). λmax = 286 nm,
ν
(C–HAr), 2932–2846
(C=OAcetate),
(N=O), 1195
, cm–1): 3012–3053
(C=ODMF), 1636
(C=Cring), 1193 (C–OPhenol), 756
= 102628 dm3 mol–1 cm–1 in
ν
(C–HAr), 2929–2847
(C=OAcetate),
ν
ν
ν
IR (
(C–HAliph), 1645
1612 (C=N), 1612
(C–HAr). λmax = 281 nm,
DMSO.
ν
ν
ν
ν
ν
ν
ν
ν
δ
ε
=
ν
ν
ν
δ
ε
°
TG: between 143 and 177°C (DMF lost) theoretical
mass loss 14.11%; found 13.53 0.63%.
{(NiSALLAC)2Mn(NO2)2(DMF)2} (VI
anal. C, 50.49; H, 5.04; N, 11.21;Ni, 11.75;Mn, 5.50.
calcd., %:
Found, %: C, 49.55; H, 4.64; N, 10.98;Ni, 12.41;Mn, 5.32.
)
{(NiSALLAC)2Mn(AcO)2(DMF)2} (III
anal. C, 53.84; H, 5.89; N, 8.18; Ni, 11.44;Mn, 5.36.
calcd., %:
Found, %: C, 54.37; H, 6.26; N, 7.98; Ni, 11.74;Mn, 5.48.
)
IR (
(C–HAliph), 1651
1596 (C=N), 1578
(C–OPhenol), 753
14855 dm3 mol–1 cm–1 in DMSO.
TG: between 201 and 261 C (DMF lost) theoretical
mass loss 14.61%; found 16.44 0.92%.
Xꢀray crystallography. single crystals of
2SALLACH2 LACH2 and complexes IV and were
analyzed on an Oxford Diffraction Xcalibur Single
Crystal Xꢀray Diffractometer with a sapphire CCD
detector using Mo radiation ( = 0.71073 ) operꢀ
scan mode. The unitꢀcell dimensions
were determined and refined by using the angular setꢀ
tings of 25 automatically centered reflections in
2.89° ≤ θ ≤ 26.37 range for 2SALLACH2 LACH2,
2.81° ≤ θ ≤ 26.36 for IV and 2.73°–27.80° for . The
data of 2SALLACH2 LACH2 were collected at
293(2) K and the data of the complexes IV and were
ν
, cm–1): 3013–3055
(C=ODMF), 1635
(C=Cring), 1314
(C–HAr). λmax = 351 nm,
ν
(C–HAr), 2932–2846
(C=OAcetate),
(N=O), 1198
ν
ν
ν
IR (
(C–HAliph), 1649
1608 (C=N), 1581
(C–HAr). λmax = 350 nm,
DMSO.
ν
, cm–1): 3019–3050
(C=ODMF), 1635
(C=Cring), 1198 (C–OPhenol), 757
ν
(C–HAr), 2934–2848
ν
ν
ν
ν
ν
ν(C=OAcetate),
ν
δ
ε
=
ν
ν
ν
δ
ε
= 15004 dm3 mol–1 cm–1 in
°
TG: between 143 and 177°C (DMF lost) theoretical
A
mass loss 14.2 %; found 13.96 1.1%.
·
V
Synthesis of complexes containing nitrite. 0.296 g
(0.001 mol) SALLACH2 was dissolved in 40.0 mL DMF
by heating. The temperature was raised up to 95 to
K
λ
Å
α
ating in
ω/2θ
110
0.237 g (0.001 mol) NiCl2
DMF (50/50, v/v) and the solution of 0.005 mole reꢀ
lated metal salt in 10 mL hot DMF, 0.238 g NiCl2
6H2O for complex IV, 0.170 g CuCl2 2H2O for V and
0.198 g MnCl2 4H2O for VI and the solution of
°
C. To this solution, added were the solution of
·
6H2O salt in 10 mL MeOH :
°
·
·
°
V
·
·
·
V
0.198 g (0.003 mol) NaNO2 salt in 10 mL hot MeOH.
The final solution was allowed to stand for 5 to 6 days.
The formed green crystalline complex was separated
by vacuum filtration and air dried.
collected at 105(2) K. The empirical absorption corꢀ
rections were applied by the semiꢀempirical method
via the CrysAlis CCD software [23]. Models were obꢀ
tained from the results of the cell refinement and the
data reductions were carried out using the solution
software SHELXL97 [24]. The structures of
{(NiSALLAC)2Ni(NO2)2(DMF)2} (IV
anal. calcd., %: C, 50.30; H, 5.03; N, 11.17; Ni, 17.56.
Found, %: C, 49.38; H, 5.3; N, 10.62; Ni, 18.26.
)
2SALLACH2
solved by direct methods using the SHELXSꢀ97 softꢀ
ware implemented in the WinGX package [25].
Crystallographic data of 2SALLACH2 LACH2, IV
and are shown in Table 1. The selected bond lengths
and angles are listed in Table 2. Supplementary mateꢀ
rial for structures 2SALLACH2 LACH2 and comꢀ
plexes IV has been deposited with the Cambridge
Crystallographic Data Centre (nos. 892463
· LACH2 and complexes IV and V were
·
IR (
(C–HAliph), 1652
1595 (C=N), 1573
(C–OPhenol), 751
12207 dm3 mol–1 cm–1 in DMSO.
ν
, cm–1): 3012–3055
(C=ODMF), 1638
(C=Cring), 1313
(C–HAr). λmax = 351 nm,
ν
(C–HAr), 2930–2854
(C=OAcetate),
(N=O), 1195
V
ν
ν
ν
ν
ν
ν
·
ν
δ
ε
=
,
V
,
892464,
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

SYNTHESIS, CRYSTAL STRUCTURE, CHROMATOGRAPHIC SEPERATION
575
Table 1. Crystallographic and experimental data of 2SALLACH2 · LACH2, {(NiSALLAC)2Ni(NO2)2(DMF)2} (IV) and
{(NiSALLAC)2Cu(NO2)2(DMF)2} (
V)
Value
Parameter
2SALLACH2 · LACH2
IV
V
M
887.06
293
1007.86
105
1003.03
293
T
, K
Crystal size, mm
Crystal system
0.5
×
0.4
×
0.1
0.32
Monoclinic
21/
×
0.26
×
0.14
0.40
Monoclinic
21/
×
0.30 0.04
×
Triclinic
P
c
P
c
Space group
P1
a
, Å
, Å
6.7527(2)
19.9830(10)
20.0070(10)
65.555(5)
82.542(4)
86.702(3)
2436.91(19)
2
10.5019(5)
20.1010(9)
10.2154(4)
90.00
10.5206(5)
20.1224(9)
10.2866(5)
90.00
b
c
, Å
, deg
, deg
, deg
α
β
90.324(5)
90.00
91.389(5)
90.00
γ
, Å3
2156.42(16)
2
2177.03(18)
2
V
Z
, g cm–3
1.209
1.552
1.530
ρ
μ, mm–1
0.08
0.9613–0.9921
944
1.421
0.6592–0.8259
1046
1.351
0.6140–0.9479
1044
Tmin Tmax
–
F(000)
θ
Range, degs
2.89–26.37
2.81–26.36
2.73–27.80
–8
–24
–24
≤
≤
≤
h
k
l
≤
≤
≤
8,
24,
25
–13
–25
12
≤
≤
≤
h
k
l
≤
≤
≤
12,
17,
12
–8
–17
–12
≤
≤
≤
h
k
l
≤
≤
≤
13,
25,
12
Index ranges
Reflections collected
Reflections unique
17270
9810
9318
4406
9332
4434
R1
,
,
wR2
(
I
> 2
σ
(I))
0.0803, 0.1999
0.1418, 0.2333
9810/6/633
1.048
0.0605, 0.1525
0.0968, 0.1737
4406/0/289
1.048
0.0540, 0.1347
0.0861, 0.1547
4434/0/286
1.043
R1
wR2 (all data)
Data/restraints/parameters
GOOF of F2
Δρmax and Δρmin, e
Å–3
0.498/–0.221
0.104/–0.585
0.683/–0.415
and 936676, respectively; deposit@ccdc.cam.ac.uk ture were investigated by Xꢀray diffraction. The pluton
or http://www.ccdc.cam.ac.uk).
drawing of the molecular model obtained in the light of
the Xꢀray diffraction study is shown in Fig. 2.
RESULTS AND DISCUSSION
In Fig. 2, three Schiff base molecules are shown
separately. The first model illustrates the asymmetric
structure of the Schiff base containing C(1)–C(18)
carbons, SALLACH2. One each of methyl groups in the
molecules of the Schiff bases containing C(19)–C(36)
carbons and C(38)–C(56) carbons are highlighted with
dashed lines. These dashed lines are connected to C(29)
and C(44) of the imine groups. The probabilities of
presence of a methyl group in these molecules have
been calculated to be 64 and 36%, respectively.
All spectral data supports the isolation of SALLACH2
asymmetric Schiff base. Unfortunately, this asymmetric
Schiff base could not be obtained as single crystal. It was
reꢀcrystallized in various solvents but none of them
yielded suitable crystals for Xꢀray analysis. Only the
mixed crystal of 2SALLACH2, LACH2 has been obꢀ
tained as a single crystal. It was observed that the two
asymmetric Schiff base molecules and one symmetric
Schiff base molecule have been crystallized together.
The crystals of 2SALLACH2 · LACH2 compound/mixꢀ
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

576
ÖZ et al.
Table 2. The selected bond lengths (Å) and angles (deg) for 2SALLACH2 · LACH2 and complexes IV
, V
Bond d, Bond
Å
d, Å
2SALLACH2 · LACH2
C(29)–N(4)
C(7)–N(1)
C(7)–H(7)
C(8)–N(1)
1.265(4)
0.9300
1.282(5)
1.512(8)
1.454(15)
1.452(4)
1.276(4)
1.455(4)
1.486(5)
1.294(4)
C(29)–C(36
C(44)–C(56
C(45)–N(5)
C(44)–N(5)
C(47)–N(6)
C(48)–C(56
C(48)–N(6)
B
)
)
1.450(4)
1.290(4)
1.503(4)
1.456(4)
1.284(4)
1.456(4)
B
C(11)–N(2)
C(11)–C(18)
C(10)–N(2)
C(25)–N(3)
C(26)–N(3)
A
)
IV
N(1)–Ni(1)
N(2)–O(5)
N(2)–O(4)
N(2)–Ni(1)
N(3)–Ni(1)
Ni(1)–O(3)
Ni(1)–O(1)
Ni(1)–O(2)
2.006(4)
1.203(5)
1.285(5)
2.135(4)
2.017(4)
2.001(3)
2.017(3)
2.165(3)
Ni(1)–Ni(2)
Ni(2)–O(1)
Ni(2)–O(1)
Ni(2)–O(3)
Ni(2)–O(3)
Ni(2)–O(4)
Ni(2)–O(4)
Ni(2)–Ni(1)
2.9789(5)
2.034(3)
2.034(3)
2.047(3)
2.047(3)
2.099(3)
2.099(3)
2.9789(5)
V
N(1)–Ni(1)
N(2)–Ni(1)
N(3)–O(4)
N(3)–O(3)
N(3)–Ni(1)
O(1)–Ni(1)
O(1)–Cu(1)
O(2)–Ni(1)
O(2)–Cu(1)
O(3)–Cu(1)
O(5)–Ni(1)
2.024(5)
2.016(5)
1.227(6)
1.287(6)
2.152(5)
1.997(4)
2.040(3)
2.021(3)
2.039(3)
2.102(3)
2.162(4)
Ni(1)–Cu(1)
Cu(1)–O(2)
Cu(1)–O(1)
Cu(1)–O(3)
Cu(1)–Ni(1)
C(7)–N(1)
2.9858(6)
2.039(3)
2.040(3)
2.102(3)
2.9858(6)
1.267(8)
1.536(9)
1.270(8)
1.452(8)
0.9500
C(7)–C(21)
C(11)–N(2)
C(11)–C(12)
C(11)–H(11)
C(7)–C(21)
1.536(9)
2SALLACH2 · LACH2
Angle
ω
, deg
Angle
ω
, deg
N(4)C(29)C(30)
N(1)C(7)C(6)
121.7(3)
119.1
118.0(4)
121.2(4)
120.7(4)
122.9(6)
119.1(3)
116.6(6)
117.1(3)
121.8(3)
121.1(3)
N(1)C(7)H(7)
C(6)C(7)H(7)
N(4)C(29)C(36
B
)
B
)
119.1
C(30)C(29)C(36
)
N(2)C(11)C(12)
N(2)C(11)C(18)
C(12)C(11)C(18)
N(3)C(25)C(24)
117.6(3)
121.5(3)
120.9(3)
117.4(3)
122.6(3)
120.0(3)
N(5)C(44)C(56
B
N(5)C(44)C(43)
C(56B)C(44)C(43)
N(6)C(48)C(49)
N(3)C(25)C(36
A
)
N(6)C(48)C(56
A
)
C(24)C(25)C(36
A
)
C(49)C(48)C(56
A)
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

SYNTHESIS, CRYSTAL STRUCTURE, CHROMATOGRAPHIC SEPERATION
577
Table 2. (Contd.)
Angle
ω
, deg
Angle
ω
, deg
IV
O(3)Ni(1)N(1)
171.75(14)
89.65(16)
98.44(18)
81.63(11)
90.28(14)
171.28(16)
83.63(15)
96.89(17)
97.13(16)
81.57(14)
91.17(14)
86.89(17)
92.40(15)
88.21(13)
N(2)Ni(1)O(2)
O(1)Ni(2)O(4)
O(3)Ni(2)O(4)
O(1)Ni(2)O(4)
O(3)Ni(2)O(4)
C(1)O(1)Ni(1)
C(1)O(1)Ni(2)
Ni(1)O(1)Ni(2)
C(19)O(2)Ni(1)
C(17)O(3)Ni(1)
C(17)O(3)Ni(2)
Ni(1)O(3)Ni(2)
N(2)O(4)Ni(2)
169.10(15)
84.06(12)
84.29(12)
84.06(12)
84.29(12)
125.0(3)
138.9(3)
94.67(12)
115.2(3)
123.0(3)
139.3(3)
94.75(12)
112.0(3)
O(3)Ni(1)N(3)
N(1)Ni(1)N(3)
O(3)Ni(1)O(1)
N(1)Ni(1)O(1)
N(3)Ni(1)O(1)
O(3)Ni(1)N(2)
N(1)Ni(1)N(2)
N(3)Ni(1)N(2)
O(1)Ni(1)N(2)
O(3)Ni(1)O(2)
N(1)Ni(1)O(2)
N(3)Ni(1)O(2)
O(1)Ni(1)O(2)
V
O(1)Ni(1)N(2)
O(1)Ni(1)O(2)
N(2)Ni(1)O(2)
O(1)Ni(1)N(1)
N(2)Ni(1)N(1)
O(2)Ni(1)N(1)
O(1)Ni(1)N(3)
N(2)Ni(1)N(3)
O(2)Ni(1)N(3)
N(1)Ni(1)N(3)
O(1)Ni(1)O(5)
N(2)Ni(1)O(5)
171.05(17)
81.70(13)
89.46(17)
89.70(18)
99.2(2)
O(2)Ni(1)O(5)
N(1)Ni(1)O(5)
N(3)Ni(1)O(5)
O(2)Cu(1)O(3)
O(1)Cu(1)O(3)
O(2)Cu(1)O(3)
O(1)Cu(1)O(3)
N(1)C(7)C(6)
N(1)C(7)C(21)
C(7)N(1)Ni(1)
C(11)N(2)Ni(1)
C(10)N(2)Ni(1)
88.16(14)
93.32(17)
168.26(16)
83.79(14)
83.89(14)
83.79(14)
83.89(14)
123.2(5)
171.32(18)
83.03(16)
97.0(2)
80.73(16)
97.10(18)
91.68(15)
86.58(19)
120.7(6)
124.2(4)
123.2(4)
119.2(4)
Similarly, the probability of C(36B) carbon is 36% than the first one. In Fig. 2 only the location of H(7)
and therefore a hydrogen atom is bonded to C(25) in
64% of the time. In this case, the third model containꢀ
ing C(38)–C(56) is the symmetric LACH2. The probꢀ
atom has been marked. In this imine bond the distance
of C=N is the shortest. The hydrogen has been placed
geometrically. For this reason, it would not be just to
use the length C(7)–H(7) for comparison. However, if
methyl is bonded to the imine bond, the distance of
abilities of C(56A) and C(56B) are 80 and 20%, reꢀ
spectively. This means that hydrogen is bonded to
C(44) 20% of the time. On the other hand, the probaꢀ
bility of hydrogen being bonded to C(48) is 80% which
points that within these probabilities, the second modꢀ
el is the symmetric LACH2.
C–C rises up, to around 1.5
were selected from the imine bond environment,
therefore all are around 120
Å. The given bond angles
°
.
1
In Figs. 3 and 4, mass and H NMR spectra of
SALLACH2 are shown, respectively. In the mass specꢀ
trum, = 296 is the molecular peak. The molecular
peaks of the symmetric Schiff bases ( = 282 and 310)
were not detected in the spectrum of SALLACH2. On the
other hand, the base peak is = 148. Other peaks beꢀ
long to the fragments with ratios 175, 162, 134, 120,
107, 91 and 77. The formation of these fragments from
SALLACH2 is given below:
In every case, two of the Schiff bases are asymmetꢀ
ric where the other one is symmetric in the crystal netꢀ
work. The HPLC result shows 67 : 33 asymmetricꢀ
symmetric Schiff base ratios. This supports the results
of the Xꢀray diffraction stoichiometrically.
The bond lengths given in the Table 2 indicate the
asymmetry, i.e. C(7)–N(1) imine bond length is
m/z
m/z
m/z
m/z
1.265
the range 1.276 and 1.294
Å
and the lengths of the other imine bonds are in
, being a little bit higher
Å
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

578
ÖZ et al.
C(14)
C(13)
C(11)
C(12)
O(2)
C(10)
C(9)
C(18)
N(2)
O(1)
N(1)
C(15)
C(16)
C(17)
C(2)
C(8)
C(1)
C(6)
C(7)
C(3)
C(4)
C(5)
C(28)
C(27)
O(3)
C(20)
C(19)
C(36
B)
N(3)
C(26)
C(39)
O(5)
C(25)
C(24)
C(40)
C(41)
N(4)
C(29)
C(36A
)
C(38)
C(23)
C(22)
C(31)
C(32)
C(43)
C(42)
O(4)
N(5)
C(51)
O(6)
C(45)
C(47)
C(33)
N(6) C(46)
C(48)
C(34)
C(52)
C(56B)
C(53)
C(54)
Fig. 2. The molecular model of the mixed crystal 2SALLACH
· LACH .
2 2
%
148
100
162
50
0
296
134
107
91
175
77
41
51
298
253
190
239
279
336 352
211
50
100
150
200
250
300
350
m
T
/z
Fig. 3. The mass spectrum of SALLACH obtained by Inlet prob, 2.024 s in the ion chromatogram (
= 153°C).
2
2.1 2.0
, ppm
3.8 3.7 3.6
7.6 7.4 7.2 7.0 6.8
δ
17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
, ppm
δ
1
Fig. 4. H NMR spectrum of refined and recrystallized SALLACH .
2
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

SYNTHESIS, CRYSTAL STRUCTURE, CHROMATOGRAPHIC SEPERATION
579
+
+
•
N
CH
CH
N
(CH2)3 C(CH3)
HO
OH
OH
m
/z
=120
+H•
m/
z
= 296
CH2•
OH
m/z =107
+
+
CH2•
CH
N
(CH2)2 CH2•
C(CH3) (CH2)2
OH
m
/
z
= 162
= 148
OH
m/
z
= 176
+
–H•
CH
N
CH2•
CH2
m
/
z
+
CH2•
C(CH3) (CH2)2
OH
+
•
O
N CH2•
CH
m/z = 175
m/z = 134
OH
Two different imine groups are detected in the 1H
NMR spectrum of SALLACH2. The singlet at
8.58 ppm in Fig. 4 belongs to the iminic proton close
to salicylaldehyde. The signal of the methyl group
bonded to the other imine is seen at 2.40 ppm, again as
a singlet. The asymmetry in the molecule is responsiꢀ
ble for the difference of the signals of two phenolic
protons, one of which at 16.55 and the other one at
13.47 ppm.
phenolic protons. Such difference cannot be exꢀ
plained by the electronegativity of a methyl group. It is
likely that this difference emerged from the hydrogen
bond between the nitrogen atom of the imine group
and the phenolic hydroxide. The spectral effect of the
hydrogen bonding in such Schiff bases have been long
known since 1961 [26–28]. Therefore, the explanaꢀ
tion should be just. The strong hydrogen bond vigorꢀ
ously affected the spectral features of the molecule.
Especially in the IR spectra, hydrogen bonding hides
A similar case is observable for the trimethylene
bridge between the imine groups. The asymmetry
makes –CH2– protons different. While the methylene
protons close to 2ꢀhydroxybenzaldehyde gave triplet at
3.66 ppm, the methylene protons at the other side gave
a clear triplet at 3.73 ppm. The protons of the centerꢀ
ing methylene are affected considerably less by the
asymmetry. These protons have been noticed as a penꢀ
tet at 2.06 ppm. In the case of a significant asymmetry,
the signal from these protons should be expected as a
multiplet because that the protons of the neighboring
CH2 groups are not conjugates. Although not expected,
this case can be explained. The asymmetry by the methyl
group bonded to the imine group affected the neighborꢀ
ing methylene protons but the impressed 0.13 ppm difꢀ
ference was not powerful enough to be effective over
the central methylene protons which force a 4 + 1 spin
spin splitting resulting a pentet. At this point the noꢀ
the
lowerꢀenergy levels. A great number of studies have
ν
(O–H) stretching or forces a shift to 1000 cm–1
…
been reported on spectral effects of O–H N= hydroꢀ
gen bonds [26–28]. At the same time, this hydrogen
bond is one of the shortest hydrogen bonds known
[29]. For this reason, although the methyl group in the
imine bond is not very effective on the chemical shift,
…
it can affect the O–H N= hydrogen bond quite sigꢀ
nificantly which creates the variation between the
δ
values of two phenolic protons.
13C NMR spectrum also supports the findings, the
signals of 18 different carbon atoms were noticed. On
the other hand, in the FTꢀIR spectrum of SALLACH2,
two different ν(C=N) streching vibrations were detected.
One of these was observed at 1631 cm–1 and the other
ticeable thing is the 3 ppm difference between two one was at 1610 cm–1.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

580
ÖZ et al.
Table 3. Thermoanalytical data of complexes I–VI
First thermal reaction (DMF lost)
Second thermal reaction (decomposition)
Complex
temperature
interval, °C
theoretical
mass loss, %
found
mass loss, %
temperature
interval, °C
found
mass loss, %
I
157–185
123–158
154–187
197–253
191–255
201–261
14.17
14.11
14.23
14.56
14.49
14.61
14.02 0.95
13.53 0.63
13.96 1.18
15.17 1.33
15.24 0.85
16.44 0.92
325–380
343–395
350–402
380–490
375–465
390–481
19.40 2.56
22.43 3.34
19.36 3.86
23.45 3.55
21.65 2.86
22.48 1.97
II
III
IV
V
VI
ν
(C=N) Stretching of LACH2 was observed at revealed that the nuclear structure of these complexes
was in the form of NiII–NiII–NiII, NiII–CuII–NiII and
NiII–MnII–NiII.
1608 cm–1 while LH2’s
(C=N) stretching was obꢀ
ν
served at 1629 cm–1. The vibration which has been obꢀ
served around 1610 cm–1 most probably belonged to
TG study was used for determination of the stoichiꢀ
ometry and characterization of complexes. In thermal
decomposition of the complexes, the first group leaved
from the structure is coordinated DMF. Theoretical
and found mass loss is compatible and this proves that
stoichiometry of the complexes (Table 3).
ν
(C=N) stretching of the group close to the acetopheꢀ
none side. This vibration must have interfered with the
(C=C) stretching of LH2; because (C=N) stretchꢀ
ing of LH2 has been found to be a sharp peak but in the
spectrum of SALLACH2 the peak at 1610 cm–1 is even
stronger.
stretching of LH2 are approximately at the same enerꢀ
gy (1608 and 1610 cm–1) and both contributes the
same energy in the case of SALLACH2. Because of
this, the peak at 1610 cm–1 has been strengthened.
With the zoom feature of the instrument the area of
1500–1700 cm–1 was examined and the presence of a
shoulder shape around 1607–1608 cm–1 can be seen.
ν
ν
At first thermal reaction for complexes containing
nitrite, regular mass loss corresponds to the mass of
ν
(C=N) Stretching of LACH2 and (C=C)
ν
DMF at between 200–260
taining acetate at between 120–180
second thermal reaction of complexes containing niꢀ
trite is exothermic at between 400–480 C and of comꢀ
plexes containing acetate at between 330–400 C.
°
C and for complexes conꢀ
°C (Table 3). The
°
°
Second thermal reaction is probably decomposition of
the residue. There is a research about thermal decomꢀ
position of trinuclear complexes of LH2 in literature
[32]. In this study, the second thermal reaction has
been reported as endothermic and the first thermal reꢀ
action has been reported at lower temperature. Howꢀ
ever, in our study, second thermal reaction of prepared
complexes using with SALLACH2 is exothermic.
After these spectral examinations it was made sure
that the asymmetric Schiff base was isolated and its
complexes were studied for further evidence. The
symmetric LH2 has been known since 1946 and dozꢀ
ens of complexes of it have been prepared [30]. A comꢀ
plex having mononuclear square planar structure has
been prepared with this Schiff base [31]. Later on diꢀ
nuclear and trinuclear complexes have been prepared
by using these mononuclear complexes [7–12]. Howꢀ
ever, there has not been any data in the literature on
mononuclear and polynuclear complexes of LACH2.
Despite the effort, unfortunately, we could not isolate
mononuclear Ni(II) complex of SALLACH2. Howevꢀ
er, several trinuclear complexes of SALLACH2 have
been prepared in DMF by template synthesis method
In addition, NiL mononuclear complex can be
prepared with LH2 and Ni(II) [31]. Trinuclear comꢀ
plexes can be prepared with symmetrical Schiff base
and NiL in two steps however in this study, it was not
possible two step preperation because NiSALLAC
could not be prepared. In this study, complexes were
prepared with template method as described in experꢀ
imental section.
Judging by this point, NiSALLAC complex could
according to the literature. Acetate, nitrite and nitrate not be considered as stable. After leaving coordinated
salts coordinated with mononuclear NiL complex DMF, the remaining units are NiSALLAC and metal
with
complexes were formed. Acetate, nitrite and nitrate
anions of the metals joined in trinuclear complexes via
bridge [7, 8, 11]. In this study, 6 trinuclear complexes
were prepared with SALLACH2 and acetate or nitrites
μ bridges using phenolic oxygens and trinuclear acetate or nitrite. Octahedral coordination of terminal
Ni2+ ions are distorted and Ni2+ ions are fiveꢀmember
coordination sphere [33]. Remaining portion can be
stable up to a certain temperature according to coordiꢀ
native strength of acetate or nitrite and after this cerꢀ
μ
of Ni(II), Cu(II) and Mn(II) metals. These complexes tain temperature begin to decomposition. However, if
characterized by IR, TG and AAS methods. Literature NiSALLAC is unstable, decomposition will probably
data, FTꢀIR spectra, TG and atomic absorption studies exothermic.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

SYNTHESIS, CRYSTAL STRUCTURE, CHROMATOGRAPHIC SEPERATION
581
Suitable crystals of {(NiSALLAC)2Ni(NO2)2(DMF)2}
IV) and {(NiSALLAC)2Cu(NO2)2(DMF)2} ( ) comꢀ
(a)
(
V
plexes were obtained and structures of these complexes
were determined by XRD. In Fig. 5, the molecular models
of these complexes drawn by Pluton are shown. Terminal
Ni atoms are located inside the octahedral coordinaꢀ
tion sphere among N3O3 donor atoms. Two out of
three nitrogen donors are nitrogen atoms of
SALLAC2– anion and the other one is the nitrogen atꢀ
om of the nitrite ion. Similarly two out of three oxygen
donors are the phenolic oxygens of SALLAC2– anion
and the other one is of a DMF molecule. These donors
have formed a facial octahedron. Central Cu and Ni
atoms also have an O6 coordination sphere. Central
C(4)
C(3)
C(5)
C(2)
C(6)
C(20)
C(1)
N(4)
O(5)
N(1)
O(1)
C(8)
Ni(2)
O(4)
O(2)
C(9)
N(3)
O(3)
C(10)
C(11)
C(18)
C(12)
Cu2+ and Ni2+ ions are located between four phenolic
oxygens of two SALLAC2– anions and one oxygen of
the nitrite groups. The phenolic oxygens and nitrite
ions coordinate both terminal and central ions via a
C(16)
C(15)
C(14)
μ
ꢀbridge. The values given in Table 2 indicate that the
octahedrons are not ideal. The largest angles of comꢀ
plex V around Ni2+ ion are N(2)N(1)O(1) 171.05
N(1)Ni(1)O(2) 171.32 and N(3)N(1)O(5) 168.26
On the other hand, the longest bonds around Ni2+ ion
are Ni–N(5) 2.162 and Ni–O(5) 2.152
°
,
°
°.
(b)
Å
.
C(14)
C(15)
Although the N(3)Ni(1)O(5) angle is equal to
168.26 , the bond lengths indicate that the apical poꢀ
sition of the octahedron is around N(3)Ni(1)O(5).
Whereas the largest angles of terminal Ni2+ ions of
complex IV are N(2)Ni(1)O(2) 169.10°, N(1)Ni(1)O(3)
°
C(13)
C(12)
C(16)
C(19)
171.75°, N(3)Ni(1)O(1) 171.28
bonds around terminal Ni2+ ions are Ni–N(2) 2.135
and Ni–O(2) 2.165 . The N(2)–Ni–O(1) direction
can be called as apical axis of this complex. However,
considering the general terms, the distortion of the ocꢀ
tahedron can be said to be low. For the distortions
around central Cu2+ and Ni2+ ions, a clear cut stateꢀ
ment would not be just because some of the bond anꢀ
° and the longest
N(4) O(2)
N(2)
C(10)
Å
Cu(1)
O(1) O(3)
O(5)
C(9)
N(1)
O(4)
C(1)
C(6)
C(8)
C(7)
C(21)
C(2)
C(3)
C(4)
gles have been calculated as 180.0° due to the symmeꢀ
1
try. It was not possible to take the H NMR and
13C NMR spectra of the complex, because the comꢀ
plex hardly dissolves in DMF. But as it was referred in
the experimental part, the results from FTꢀIR, eleꢀ
mental and TG analysis were found to be in good
agreement. The mass of the DMF molecules coordiꢀ
nating the terminal Ni2+ ions were found to be 15.24
0.85% and 15.17 1.33 in average. It is quite close to
the theoretically expected result being 14.50 and
14.56%, respectively. In the FTꢀIR spectrum of the
C(5)
Fig. 5. PLUTON drawings of complexes IV (a) and
V (b).
ACKNOWLEDGMENTS
Financial support of this work by the University of
Ankara Scientific Research Fund (contract
and Ahi Evran University Scientific
no. 12B4240003)
Research Fund (contract no. 4001.12.014) are grateꢀ
fully acknowledged. We are indebted to and thank
Prof. Dr. Wolfgang Donner for providing laboratory
facilities at TU Darmstadt.
complex, (C=N) streching vibrations were observed at
ν
1598 cm–1. So the energy of these vibrations shifted apꢀ
proximately 33 cm–1 in comparison with the ligand alone
which was the expected outcome [34, 35]. The data in
Table 2 indicate no significant change in bond lengths
of the ligand in case of complex formation.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014

582
ÖZ et al.
18. Shebl, M., Khalil, S.M.E., Ahmed, S.A., and Mediꢀ
en, H.A.A., J. Mol. Struct., 2010, vol. 980, p. 39.
19. Kolawole, G.A and Osowole, A.A., J. Coord. Chem.,
2009, vol. 62, p. 1437.
20. Ghosh, M., Fleck, M., Mahanti, B., et al., J. Coord.
Chem., 2012, vol. 65, p. 3884.
21. Fee, W.W., Pulsford, J.D., and Vowles, P.D., Aust.
J. Chem., 1973, vol. 26, p. 1459.
22. Atakol, O., Boca, R., Ercan, I., et al., Chem. Phys.
Lett., 2006, vol. 423, p. 192.
REFERENCES
1. Peiffer, P., Breith, E., L
Annal. Chim., 1933, vol. 502, p. 84.
2. Martell, A.E and Calvin, M., Die Chemie der Metallchelat
Verbindungen, Weinheim: Verlag Chemie, 1958, p. 199.
übbe, E., and Tsumaki, T.,
.
.
ꢀ
3. Kato, M., Jonassen, H.B., and Fanning, J.C., Chem.
Rev., 1964, vol. 64, p. 99.
4. Kato, M. and Muto, Y., Coord. Chem. Rev., 1988,
vol. 92, p. 45.
5. Metalobos, J.S., Deibe. A.M.G., Fondo, M., et al.,
Inorg. Chem. Commun., 2004, vol. 7, p. 311.
23. Oxford Diffraction CrysAlis CCD and CrysAlis RED, Verꢀ
sion 1.170.14, Oxfordshire (England): Oxford Diffracꢀ
tion, 2002.
6. Bhowmik, P., Drew, M.G.B., and Chattopadhyay, S.,
Inorg. Chim. Acta, 2011, vol. 366, p. 62.
24. Sheldrick, G.M., SHELXSꢀ97 and SHEXLꢀ97, Proꢀ
gram for Crystal Structure Solution and Refinement
ttingen (Germany): Univ. of G ttingen, 1997.
25. Farrugia, L.J., J. Appl. Cryst., 1999, vol. 32, p. 837.
26. Freedmann, H.H., J. Am. Chem. Soc., 1961, vol. 83,
p. 2900.
,
7. Fukuhara, C., Tsuneyoshi, K., Matsumoto, N., et al.,
Dalton Trans., 1990, p. 3473.
G
ö
ö
8. Uhlenbrock, S., Wegner, R., and Krebs, B., Dalton
Trans., 1996, p. 3731.
9. You, Z.L., Zhu, H.L., and Liu, W.S., Z. Anorg. Allg.
Chem., 2004, vol. 630, p. 1617.
27. Golubev, N.S., Smirnov, S.N., Tolstoy, P.M., et al.,
J. Mol. Struct., 2007, vol. 844, p. 319.
10. Song, Y., Gomez, P., Roubeau, O., et al., Inorg
Acta, 2005, vol. 358, p. 109.
. Chim.
28. U
Struct., 2010, vol. 984, p. 232.
29. Steiner, T., Angew. Chem Int. Ed., 2002, vol. 41, p. 48.
30. Bailes, R.H and Calvin, M., J. Am. Chem. Soc., 1947,
zarevic, K., Rubcic, M., Stilinovic, V., et al., J. Mol.
11. Regliski, J., Taylor, M.K., and Kennedy, A.R., Inorg.
Chem. Commun., 2006, vol. 9, p. 736.
.
.
12. Yu, T., Zhang, K., Zhao, Y., et al., Inorg. Chem.
Commun., 2007, vol. 10, p. 401.
13. Mustapha, A., Busche, C., Reglinski, J., and Kenꢀ
vol. 69, p. 1886.
31. Drew, M.G.B., Prasad, R.N., and Sharma, R.P., Acta
Crystallogr., C, 1985, vol. 41, p. 1755.
nedy, A.R., Polyhedron, 2011, vol. 30, p. 1530.
¸
s, S., Ergun, U., Jaud, J.C., et al., J. Therm.
32. Durmu
Anal. Cal., 2006, vol. 86, p. 337.
33. Atakol , O., Naz r, H., Ar , C., et al., Inorg. Chim. Acꢀ
ta, vol. 342, p. 295.
14. Munde, A.S., Jagdale, A.N., Jadhav, S.M., and Chondꢀ
hekar, T.K., J. Serbian Chem. Soc., 2010, vol. 75, p. 349.
ι
ι ι
c
15. Nejo, A.A., Kolawole, G.A., and Nejo, A.O., J. Coord.
Chem., 2010, vol. 63, p. 4398.
16. Asadi, M. and Asadi, Z., J. Coord. Chem., 2008,
34. You, Z.L., Zhu, H.L., and Liu, W.S., Z. Anorg. Allg.
Chem., 2004, vol. 630, p. 1617.
35. Nakamato, K., Infrared and Raman Spectra of Inorganꢀ
ic and Coordination Compounds, New York: WileyꢀInꢀ
terscience Publication, 1997.
vol. 61, p. 640.
17. Tang, B., Sun, X.P., Liu, G.L., and Li, H., J. Mol.
Struct., 2010, vol. 984, p. 111.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 40
No. 8
2014