Palladium(II) and platinum(II) saccharinate complexes with 2aminomethylpyridine and 2-aminoethylpyridine: synthesis, characterization, crystal structures, and thermal properties

Article abstract of DOI:10.1002/zaac.200900325

trans-[Pd(ampy)₂](sac)₂ (1), trans-[Pt(ampy) ₂](sac)₂ (2), trans-[Pd(aepy)₂](sac) ₂·2H₂O (3) and trans-[Pt(aepy)₂](sac) ₂·2H₂O (4) (sac=saccharinate, ampy=2- aminomethylpyridine and aepy = 2-aminoethylpyridine) have been synthesized and characterized by elemental analysis, FTIR, and X-ray single crystal diffraction. In all cases, the palladium(II) and platinum(II) ions sit on the center of symmetry and are coordinated, by the bidentate chelating ampy or aepy ligands, and the sac ions remain as a counterion. In complex 2, the cations and sac anions are connected by N-H...O hydrogen bonds as well as aromatic π-π stacking interactions into a two-dimensional supramolecular network, whereas in 3 and 4, they are linked by N-H...O hydrogen, bonds into chains, which are further assembled into a two-dimensional array by OW-H...O hydrogen bonds. All complexes were investigated by IR spectroscopy and thermal analyses.

Full text of DOI:10.1002/zaac.200900325

ARTICLE
DOI: 10.1002/zaac.200900325
Palladium(II) and Platinum(II) Saccharinate Complexes with 2-
Aminomethylpyridine and 2-Aminoethylpyridine: Synthesis,
Characterization, Crystal Structures, and Thermal Properties
[a]
[a]
[a]
[b]
Veysel T. Yilmaz,* Ahsen Ertem, Emel Guney, and Orhan Buyukgungor
Keywords: Palladium; Platinum; Saccharinate; 2-Aminomethylpyridine; 2-Aminoethylpyridine
Abstract. trans-[Pd(ampy)
trans-[Pd(aepy) ](sac) ·2H
2
](sac)
2
(1), trans-[Pt(ampy)
2
](sac)
·2H
2
(2), the sac ions remain as a counterion. In complex 2, the cations and sac
O (4) anions are connected by N–H···O hydrogen bonds as well as aromatic
2
2
2
O (3) and trans-[Pt(aepy)
2
](sac)
2
2
(
sac = saccharinate, ampy = 2-aminomethylpyridine and aepy = 2-amino- π–π stacking interactions into a two-dimensional supramolecular net-
ethylpyridine) have been synthesized and characterized by elemental work, whereas in 3 and 4, they are linked by N–H···O hydrogen bonds
analysis, FTIR, and X-ray single crystal diffraction. In all cases, the into chains, which are further assembled into a two-dimensional array
palladium(II) and platinum(II) ions sit on the center of symmetry and by OW–H···O hydrogen bonds. All complexes were investigated by IR
are coordinated by the bidentate chelating ampy or aepy ligands, and spectroscopy and thermal analyses.
Introduction
tivity [9, 10]. As a part of our ongoing research, we decided
to prepare ampy and aepy complexes of palladium(II) and plat-
inum(II) saccharinates. Thus we report herein the synthesis and
spectroscopic characterization and thermal properties of a se-
ries of palladium(II) and platinum(II) saccharinate complexes
The water soluble alkali salts of saccharin (sacH, also named
,1-dioxo-1,2-benzothiazol-3-one or o-benzosulfimide) are
1
widely used as a non-caloric artificial sweetener and food addi-
tive. The imino hydrogen of sacH is acidic and thus in solu-
tions, the molecule can be easily converted into the corre-
sponding nitranion, saccharinate (sac). Although metal
complexes of molecular saccharin are not known, the coordi-
nation chemistry of its anion is very interesting. Sac has differ-
ent coordination sites such as one negatively charged imino
with ampy and aepy, namely trans-[Pd(ampy) ](sac)2 (1),
2
trans-[Pt(ampy) ](sac) (2), trans-[Pd(aepy) ](sac) ·2H O (3),
2
2
2
2
2
and trans-[Pt(aepy) ](sac) ·2H O (4). The single-crystal X-ray
2
2
2
structures of complexes 2–4 are also described.
nitrogen, one carbonyl and two sulfonyl oxygen atoms. As a Experimental Section
polyfunctional ligand, it is able to form metal complexes from
mononuclear to coordination polymers, but in the case of bulky
Materials and Measurements
ligands, it sometimes remains outside the coordination sphere
as a counterion [1].
All reagents were purchased and used as supplied. The elemental anal-
yses (C, H, and N) were performed with a Costech Elemental Analyser.
We have recently reported the synthesis and structural char- IR spectra were recorded with a Thermo Nicolet 6700 FT-IR spectro-
–1
acterization of several saccharinate complexes of 2-amino- photometer as KBr pellets in the frequency range 4000–400 cm .
Thermal analysis curves (TG and DTA) were obtained from a Seiko
methylpyridine (ampy) and 2-aminoethylpyridine (aepy) li-
Exstar TG/DTA 6200 thermal analyzer in a dynamic air atmosphere
gands with various metal ions such as nickel(II) [2], copper(II)
with a heating rate of 10 K·min–1 using a sample size of 5–10 mg and
platinum crucibles.
[
3], zinc(II) [4], cadmium(II) [5], mercury(II) [6], lead(II) [7],
and silver(I) [8]. In these complexes, both the sac and aminoal-
kylpyridine ligands coordinate the metal ions. On the other
hand, it has been reported that the iron(II), copper(II), and plat-
inum(II) complexes of ampy and aepy show the antitumor ac-
Synthesis of Metal Complexes
Complexes 1 and 3 were synthesized using the following method:
Ampy or aepy (0.8 mmol) was added dropwise to a solution of di-
*
Prof. Dr. V. T. Yilmaz
2
chloro(1,5-cyclooctadiene)palladium(II), [Pd(cod)Cl ] (0.4 mmol) dis-
E-Mail: vtyilmaz@uludag.edu.tr
solved in CH Cl (40 mL) and stirred for four hours at room tempera-
2
2
[
a] Department of Chemistry
Faculty of Arts and Sciences
Uludag University
ture. Afterwards, the solid product was separated by filtration and dried
at room temperature. The solid product, presumably consisting of
16059, Bursa, Turkey
[
M(L)
2
]Cl
2
(L = ampy or aepy), was dissolved in water (30 mL) and
O (0.17 g, 0.7 mmol) was added to this solu-
[
b] Department of Physics
Faculty of Arts and Sciences
Ondokuz Mayis University
afterwards, Na(sac)·2H
tion and stirred for ca. 30 min. The resulting solution was allowed to
2
55139, Samsun, Turkey
stand at room temperature. Complex 1 was obtained as a polycrystal-
6
10
© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Z. Anorg. Allg. Chem. 2010, 636, 610–615

Palladium(II) and Platinum(II) Saccharinate Complexes
line product, whereas pale yellow crystals of 3 appeared after two vs, 1108 s, 1046 m, 948 s, 772 m, 747 m, 698 w, 674 s, 600 s, 539
–1
weeks.
m, 519 m cm .
[
Pt(aepy) ](sac)
2
O
2
·2H
2
O
(4): Yield 60.6 %. M.p. 142–147 °C.
Complexes 2 and 4 were prepared as follows: A solution of ampy or
C
28
H
32
N
6
8
S
2
Pt (839.81): calcd. C 40.0, H 3.5, N 10.0; found C 40.2,
H 3.7, N 10.1 %. IR (KBr): ν˜ = 3551 sb, 3444 sb, 3184 sb, 3101 sb,
958 vw, 1623 vs, 1581 vs, 1486 m, 1458 m, 1343 m, 1326 m, 1255
vs, 1151 vs, 1119 vs, 1051 m, 1011 w, 950 vs, 779 m, 751 m, 706 w,
aepy (0.8 mmol) in MeOH (15 mL) was mixed with a solution of
K
2
[PtCl
for 48 hours at room temperature. The yellow solid was separated and
dissolved in 200 mL water. The solid AgNO (0.14 g, 0.8 mmol) was
4
] (0.17 g, 0.4 mmol), dissolved in water (5 mL), and stirred
2
3
–1
6
75 m, 636 w, 605 s, 543 m, 468 w cm .
added to this solution and heated under reflux for six hours. The pre-
cipitate of AgCl was removed by filtering through Celite paste to ob-
tain a clear solution. Afterwards, the filtrate was concentrated to 10 mL X-ray Crystallography
followed by the addition of Na(sac)·2H O (0.8 mmol, 0.20 g) and was
2
The data collection was performed with a Stoe-IPDS-2 diffractometer
equipped with a graphite monochromated Mo-K radiation (α =
.71073 Å). The structure was solved by direct methods using
SHELXS-97 [11] and refined by a full-matrix least-squares procedure
using the program SHELXL-97 [11]. All non-hydrogen atoms were
easily found from the difference Fourier map and refined anisotropi-
cally. All carbon and amine hydrogen atoms were included using a
riding model, whereas the water hydrogen atoms were refined freely.
Details of crystal data, data collection, structure solution and refine-
ment are given in Table 1.
heated under reflux for 4 hours. The clear solution was kept at room
temperature and prismatic crystals of 2 and 4 were obtained after two
weeks.
α
0
[
Pd(ampy)
2
](sac)
Pd (687.08): calcd. C 45.5, H 3.5, N 12.2; found C 45.6,
H 3.9, N 12.2 %. IR (KBr): ν˜ = 3105 sb, 3048 s, 1638 vs, 1569 vs,
495 m, 1434 m, 1332 m, 1262 vs, 1197 m, 1140 vs, 1115 vs, 1050
2
(1): Yield 82.0 %. M.p. 248–255 °C.
26 24 6 6 2
C H N O S
1
–1
m, 944 vs, 886 m, 756 s, 678 m, 608 s, 539 m, 433 w cm .
[
Pt(ampy)
2
](sac)
Pt (775.72): calcd. C 40.2, H 3.1, N 10.8; found C 40.0,
H 2.9, N 10.6 %. IR (KBr): ν˜ = 3138 sb, 3018 sb, 2921 w, 1636 vs,
573 s, 1496 m, 1453 m, 1384 m, 1328 m, 1264 vs, 1207 w, 1144 vs,
114 vs, 1050 w, 1017 w, 948 vs, 883 m, 757 vs, 679 s, 630 w, 603
2
(2): Yield 60.4 %. M.p. 291–299 °C.
CCDC-737649 (2), CCDC-737650 (3), and CCDC-737651(4) contain
the supplementary crystallographic data for this paper. These data can
be obtained free of charge from The Cambridge Crystallographic Data
Centre via www.ccdc.cam.ac.uk/data_request/cif.
26 24 6 6 2
C H N O S
1
1
–
1
s, 542 m, 528 m, 440 m cm .
Results and Discussion
Syntheses and Spectral Properties
[
Pd(aepy)
comp.). C28
found C 44.5, H 4.2, N 10.9 %. IR (KBr): ν˜ = 3461 sb, 3281 sb, 3036
2
](sac)
2
·2H
2
O (3): Yield 48.4 %. M.p. 230–235 °C (de-
H N O S Pd (751.14): calcd. C 44.8, H 4.3, N 11.28;
32 6 8 2
Complexes 2–4 were synthesized in moderate yields,
w, 2921 w, 1629 vs, 1582 s, 1487 w, 1450 m, 1328 m, 1254 vs, 1144 whereas complex 1 was obtained in a high yield (over 80 %).
Table 1. Details of crystal data collection and refinement for 2–4.
Compound
2
3
4
Empirical formula
C
26
H
24
N
6
O
6
S
2
Pt
C
28
H
32
N
6
O
8
S
2
Pd
C
28 32 6 8 2
H N O S Pt
–
1
FW /g·mol
T /K
775.72
150
751.14
150
839.81
296
Radiation, λ /Å
Crystal system
Space group
a /Å
0.71073
0.71073
triclinic
P1
0.71073
triclinic
monoclinic
¯
¯
P1
P2
1
/c
7.2267(4)
24.0712(9)
8.5557(5)
7.9287(4)
8.0454(4)
12.5150(7)
737.19(7)
1
7.6861(10)
8.9917(12)
b /Å
c /Å
11.5101(14)
765.87(17)
1
3
V /Å
1302.61(12)
2
Z
–
3
D
c
/g·cm
1.978
5.603
760
1.692
1.821
–
1
μ /mm
0.833
4.777
F(000)
384
416
Crystal size /mm
θ range /°
Index range
0.50 × 0.41 × 0.20
1.69/26.50
0.48 × 0.30 × 0.05
1.70/28.08
–9 ≤ h ≤ 9,
–10 ≤ k ≤ 10,
–15 ≤ l ≤ 15
7884
0.54 × 0.40 × 0.27
2.35/26.49
–8 ≤ h ≤ 9,
–11 ≤ k ≤ 11,
–14 ≤ l ≤ 14
11124
–8 ≤ h ≤ 9,
–
30 ≤ k ≤ 30,
10 ≤ l ≤ 10
–
Reflections collected
9842
Independent reflections (Rint
)
2692 (0.0527)
Numerical
2692/0/187
1.047
3044 (0.0235)
Numerical
3044/3/211
1.083
3181 (0.0225)
Numerical
3181/3/211
1.114
Absorption correction
Data / restraints/ parameters
2
S on F
Final R indices [I > 2σ(I)]
wR indices (all data)
0.0252
0.0306
0.0124
0.0581
0.0779
0.0317
–
3
Largest diff. peak and hole /e·Å
1.387 and –1.657
0.553 and –0.737
0.472 and –0.701
Z. Anorg. Allg. Chem. 2010, 610–615
© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
611

V. T. Yilmaz et al.
ARTICLE
Complexes 2–4 were obtained as single crystals, but attempts tively, whereas the bands at ca. 1330 and 945 cm–1 are as-
to get single crystals of 1 failed. All complexes are non-hygro- signed to the symmetric and asymmetric stretchings of the
scopic and stable at ambient temperatures. They are soluble in CNS moiety in the sac ion.
water, MeOH, and EtOH at room temperature.
Although crystals of complex 1 were not obtained and its X-
Selected FT-IR spectroscopic data of complexes 1–4 are ray structure was not identified, the IR spectroscopic data sug-
listed in Table 2. All complexes display one or two bands in gest that its structure is similar to that of 2.
–1
the frequency range 3100–3185 cm , because of the ν(NH)
vibrations of the ampy or aepy ligands. Additional bands be-
tween 3440 and 3551 cm–1 are attributed to the ν(OH) vibra-
tions of the lattice water molecules in complexes 3 and 4. The
Description of the Crystal Structures
The molecular structure of complex 2 is illustrated in Fig-
sharp C=O stretching vibration bands of the sac ion are ob- ure 1. Selected bond lengths and angles are given in Table 3,
–1
served between 1620 and 1640 cm . The carbonyl bands cen- together with the hydrogen bonding parameters. Complex 2
tered at around 1650 cm–1 usually correspond to the monoden- consists of a centrosymmetric [Pt(ampy)2] cation and two sac
tate coordination of sac by the nitrogen atom [12], but intra- anions. In the cation, the platinum(II) ion exhibits a slightly
and intermolecular hydrogen bonding interactions involving distorted square-planar coordination arrangement with two
the carbonyl group shift this band to lower frequencies [1]. ampy ligands at the trans positions. Each ampy ligand acts as
2+
–1
Two strong bands centered at around 1265 and 1145 cm are a bidentate donor through both nitrogen atoms, resulting in the
characteristic for the ν SO and ν SO modes of sac, respec- Pt–N bond lengths of 2.017(3) and 2.051(3) Å. To the best
as
2
s
2
Table 2. Selected IR spectroscopic data for 1–4a).
1
2
3
4
ν(OH)
ν(NH)
ν(CH)
ν(CO)
ν(CN)
ν(CC)
–
–
3461sb
3551sb, 3444sb
3184sb, 3101sb
2958vw
3105sb
3048s
3138sb
3056s
3281sb
3036w, 2921w
1629vs
1638vs
1569vs
1495m, 1434m
1332m
1262vs
1140vs
944vs
1636vs
1573s
1496m, 1453m
1328m
1264vs
1144vs
948vs
1623vs
1582s
1581vs
1487w, 1450m
1328m
1486m, 1458m
1326m
ν
ν
ν
ν
s
(CNS)
as(SO
2
)
)
1254vs
1255vs
s
(SO
2
1144vs
1151vs
as(CNS)
948s
950vs
–
1
a) Frequencies in cm ; b = broad; w = weak; vs. = very strong; s = strong; m = medium.
Table 3. Selected structural data for 2–4.
Bond lengths /Å and angles /o
Compounds
2
3
4
M1–N1
2.017(3)
2.025(2)
2.050(2)
85.66(9)
94.34(9)
2.018(2)
2.059(2)
86.31(6)
93.69(6)
M1–N2
2.051(3)
N1–M1–N2
100.17(10)
79.83(10)
N1–M1–N2i
Hydrogen bonds
D–H···A
d(D–H)
d(H···A)
d(D···A)
<(DHA)
2
ii
N2–H2A···N3
0.90
0.90
2.15
2.06
2.979(4)
2.879(4)
152
150
iii
N2–H2B···O1
3
N2–H2A···O1
0.90
0.90
0.88(6)
0.88(6)
1.97
2.24
2.39(8)
2.21(5)
2.837(3)
3.025(3)
3.251(7)
3.001(7)
161
145
167(8)
149(8)
iv
N2–H2B···O3
v
O1W–H1W···O2
O1W–H2W···O1
4
N2–H2A···O2
N2–H2B···N3
O1W–H1W···O1
O1W–H2W···O1
0.90
0.90
0.90(4)
0.87(5)
2.05
2.22
2.03(2)
2.17(5)
2.942(2)
3.013(2)
2.929(3)
3.023(4)
172
146
174(5)
164(5)
vi
vii
Symmetry operations: (i) –x + 1, –y + 1, –z + 1; (ii) –x, –y + 1, –z; (iii) x + 1, y, z; (iv) x, y + 1, z; (v) x – 1, y + 1, z; (vi) x, y + 1, z + 1;
vii) –x + 1, –y, –z + 1.
(
6
12
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© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Z. Anorg. Allg. Chem. 2010, 610–615

Palladium(II) and Platinum(II) Saccharinate Complexes
of our knowledge, the X-ray structure of any palladium(II) or a cation [M(ampy) ]2+ (M = Pd or Pt ), two sac ions, and two
II
II
2
platinum(II) complex with ampy or aepy has not been reported lattice water molecules. In the complex cations, the palla-
so far, since the reported platinum(II) complex with ampy was dium(II) or platinum(II) ions lie on a center of symmetry and
based on elemental analysis data [10]. However, the Pt–N(py) are coordinated by a pair of neutral aepy ligands constituting
bond lengths are similar to those found in trans-[PtCl NH (2- a square planar MN chromophore. Each aepy ligand behaves
2
3
4
hydroxymethylpyridine)] [13]. The py rings of both ampy li- as a bidentate ligand and forms two six-membered metallocy-
gands are coplanar together with the platinum(II) ion, but the clic chelate rings, whereas the sac ions are not involved in
amino nitrogen atoms deviate by 0.536 Å from the best plane coordination as in 2. The M–N bond lengths of both complexes
of the py rings. In contrast to the previous metal complexes [2– compare well with each other and are similar to those of 2.
8
], two sac ions do not coordinate the platinum(II) and instead, Distortions in the coordination arrangement of complexes 3
remain outside the coordination sphere as counterions. How- and 4 are evident from the cis angles ranging from 85.66(9)°
ever, they are involved in intermolecular hydrogen bonding to 94.34(9)°. The py rings in 4 are coplanar, but in 3, they
with the amine hydrogen atoms of the ampy ligand, generating make a dihedral angle of 12.46°. The amine nitrogen atom and
a supramolecular network parallel to the ac plane (Figure 1). the carbon atom adjacent to it significantly deviate from the
On the other hand, there are two types of π–π interactions be- best pane of the py ring by 1.705 and 1.352 Å in 3 and 1.485
tween the phenyl rings of sac and ampy. The interplanar dis- and 1.253 Å in 4, respectively.
tance between the adjacent rings are 3.627(2) and 3.680(3) Å,
indicating significant attractive intermolecular aromatic inter-
actions.
Figure 1. (a) Molecular structure of 2 with the atom numbering
scheme. Displacement ellipsoids are drawn at the 30 % probability
Figure 2. (a) Molecular structure of 3 with the atom numbering
level. C–H hydrogen atoms are omitted for clarity. (b) Supramolecular
scheme. Displacement ellipsoids are drawn at the 30 % probability
array of 2, showing 2D network, viewed down the b axis.
level. C–H hydrogen atoms are omitted for clarity. (b) Packing of mol-
ecules of 3 into 2D network, viewed down the a axis.
The molecular views of complexes 3 and 4 are shown in
As listed in Table 3, in complex 3, the [Pd(aepy) ]2 cation
+
Figure 2 and Figure 3, respectively. The selected bond ar-
2
rangements are summarized in Table 3. Complexes 3 and 4 are and the sac anions are connected by two N–H···O hydrogen
¯
isostructural and crystallize in space group P1. They consist of bonds leading to one-dimensional chains, which are further
Z. Anorg. Allg. Chem. 2010, 610–615
© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de 613

V. T. Yilmaz et al.
ARTICLE
to distinguish the decomposition stages from the TGA curves.
The highly exothermic peak above 380 °C is characteristic for
the decomposition of the sac ions in air [14]. The decomposi-
tion of the complexes ends in the temperature range 440–
585 °C with the decomposition product PdO for the palla-
dium(II) complexes (1 and 3), and metallic platinum for the
platinum(II) complexes (2 and 4) (Table 4). PdO decomposes
to metallic palladium at higher temperatures between 750 and
850 °C.
Conclusions
In summary, reaction of palladium and platinum(II) with
ampy or aepy in the presence of Na(sac) resulted in trans-
[
[
(
Pd(ampy) ](sac)2 (1), trans-[Pt(ampy) ](sac)2 (2), trans-
2 2
Pd(aepy) ](sac) ·2H O (3), and trans-[Pt(aepy) ](sac) ·2H O
2
2
2
2
2
2
4). Except for complex 1, the other complexes are crystalline.
The single crystal structural data show that complexes 2–4
Figure 3. (a) Molecular structure of 4 with the atom numbering
scheme. Displacement ellipsoids are drawn at the 30 % probability
level. C–H hydrogen atoms are omitted for clarity. (b) Supramolecular
array of 4, showing 2D network, viewed down the a axis.
connected into two-dimensional array by water bridges involv-
ing the lattice water molecules and the oxygen atoms of the
sac ions (see Table 3 and Figure 2). Because of isomorphism,
complex 4 also possesses packing interactions similar to those
present in 3 (see Figure 3).
Thermal Decomposition Behavior
Thermal stabilities and decompositions of complexes 1–4
were studied by differential thermal analysis (DTA) and ther-
mogravimetric analysis (TGA) under a flow of dry air from 20
to 950 °C. The thermoanalytical data are given in Table 4, and
the DTA and TG curves are illustrated in Figure 4. In general,
two stages of mass loss were observed in the decomposition
of 1 and 2, whereas complexes 3 and 4 show an initial mass
loss corresponding to dehydration. The elimination of the
ampy or aepy ligands is an endothermic process and the exo-
thermic degradation of the sac moiety occurs before the re-
moval of these ligands is completed. Therefore, it is impossible Figure 4. . DTA and TG curves of 1–4.
6
14 www.zaac.wiley-vch.de © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Z. Anorg. Allg. Chem. 2010, 610–615

Palladium(II) and Platinum(II) Saccharinate Complexes
Table 4. Thermoanalytical data for 1–4.
Complex
Temperature range /°C
245–585
DTAmax /°Ca)
Mass loss / %b)
Solid residue
1
248(+), 536(–)
83.5 (81.9)
3.2 (2.6)
PdO
Pd
772–844
819(+)
2
3
275–537
25–200
295 (+), 447(–), 471(–)
75.7 (74.9)
4.6 (4.8)
Pt
139(+)
[Pd(aepy)
PdO
2 2
](sac)
2
7
20–518
50–827
222(+), 232(+), 256(+), 474(–)
78.6 (78.9)
2.6 (2.1)
809(+)
68(+)
Pd
[Pt(aepy)
Pt
4
25–125
5.0 (4.3)
2 2
](sac)
1
90–440
220(+), 270(+), 292(+), 391(–)
71.6 (72.4)
a) (+) and (–) donate endothermic and exothermic processes, respectively; b) Calculated values are given in parentheses.
consist of a centrosymmetric [M(L) ] cation (M = PdII or
2+
[
[
[
2] V. T. Yilmaz, S. Caglar, W. T. A. Harrison, Transition Met. Chem.
2
II
2004, 29, 477.
Pt and L = ampy or aepy) and two sac anions. Additionally,
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Acknowledgement
[
This work is a part of a research project 106T664. We thank TUBITAK
for the financial support given to the project.
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8
References
Received: July 1, 2009
Published Online: September 8, 2009
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© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
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