New coordination compounds based on Cd(NCS)2(4-ethylpyridine) x (x = 4, 2, 1)

Article abstract of DOI:10.1002/zaac.201200479

The reactions of different ratios of cadmium(II) thiocyanate and 4-ethylpyridine as neutral co-ligand in water at room temperature leads to the formation of the three new coordination compounds of different topology. In the crystal structure of the 1:4 compound (1:4 = ratio between metal and neutral co-ligand) Cd(NCS)₂(4-ethylpyridine)₄ (1) discrete complexes are found, in which the cadmium ions are coordinated by two terminal N-bonded anionic ligands and four 4-ethylpyridine co-ligands. In the crystal structure of the 1:2 compound [Cd(NCS)₂(4-ethylpyridine) ₂]_n (2) the cadmium cations are coordinated by two S-bonded, two N-bonded thiocyanato anions and two 4-ethylpyridine ligands, all of them are trans-oriented. The Cd²⁺ cations are connected by μ-1, 3 bridging thiocyanato anions into chains, which elongate in the direction of the crystallographic a axis. In the crystal structure of the 1:1 compound [Cd(NCS)₂(4-ethylpyridine)]_n (3) a more condensed coordination network is observed, in which each Cd²⁺ cation is coordinated by two N-bonded and three S-bonded as well as one 4-ethylpyridine ligand within slightly distorted octahedra. The cadmium cations are linked into chains by μ-1, 3- and μ-1, 1, 3-bridging thiocyanato anions. On heating the 1:4 compound 1 two mass steps are observed in the TG curve, of which the first one is well resolved. The residue obtained after the first TG step is investigated by XRPD, elemental analysis, and IR spectroscopy, it is proven that the 1:2 compound Cd(NCS)₂(4-ethylpyridine)₂ is obtained as a phase pure material. Based on the results of IR spectroscopic investigations the coordination mode of the thiocyanato anions was additionally investigated. Copyright

Full text of DOI:10.1002/zaac.201200479

ARTICLE
DOI: 10.1002/zaac.201200479
New Coordination Compounds Based on Cd(NCS)2(4-Ethylpyridine)x
(x = 4, 2, 1)
Susanne Wöhlert,[a] Inke Jess,[a] and Christian Näther*[a]
Keywords: Coordination polymers; Cadmium; Crystal structures; Thermal properties
Abstract. The reactions of different ratios of cadmium(II) thiocyanate elongate in the direction of the crystallographic a axis. In the crystal
structure of the 1:1 compound [Cd(NCS)2(4-ethylpyridine)]n (3) a
more condensed coordination network is observed, in which each Cd2+
cation is coordinated by two N-bonded and three S-bonded as well
as one 4-ethylpyridine ligand within slightly distorted octahedra. The
cadmium cations are linked into chains by μ-1,3- and μ-1,1,3-bridging
thiocyanato anions. On heating the 1:4 compound 1 two mass steps
are observed in the TG curve, of which the first one is well resolved.
The residue obtained after the first TG step is investigated by XRPD,
elemental analysis, and IR spectroscopy, it is proven that the 1:2 com-
pound Cd(NCS)2(4-ethylpyridine)2 is obtained as a phase pure mate-
rial. Based on the results of IR spectroscopic investigations the coordi-
and 4-ethylpyridine as neutral co-ligand in water at room temperature
leads to the formation of the three new coordination compounds of
different topology. In the crystal structure of the 1:4 compound (1:4 =
ratio between metal and neutral co-ligand) Cd(NCS)2(4-ethylpyridine)4
(1) discrete complexes are found, in which the cadmium ions are coor-
dinated by two terminal N-bonded anionic ligands and four 4-ethylpyr-
idine co-ligands. In the crystal structure of the 1:2 compound
[Cd(NCS)2(4-ethylpyridine)2]n (2) the cadmium cations are coordi-
nated by two S-bonded, two N-bonded thiocyanato anions and two 4-
ethylpyridine ligands, all of them are trans-oriented. The Cd2+ cations
are connected by μ-1,3 bridging thiocyanato anions into chains, which nation mode of the thiocyanato anions was additionally investigated.
to their paramagnetic analogues, the structures of the latter can
be determined by Rietveld refinement.[19–21]
Introduction
Recently, we have reported on the synthesis of transition
In this context we have reported on cadmium thiocyanato
metal thiocyanato coordination polymers, in which the cations coordination polymers based on pyridine as neutral co-li-
are linked by μ-1,3-bridging anionic ligands that can mediate gand.[22] Within these investigations we have obtained three
magnetic exchange.[1–4] Unfortunately, if the synthesis is per- different modifications of [Cd(NCS)2(pyridine)2]n, in which
formed in solution, in most cases discrete complexes are ob- the cadmium cations are always coordinated by two N-bonded
tained, in which the thiocyanato anions are terminal N-bonded and two S-bonded thiocyanato anions as well as two pyridine
indicating that this coordination is more stable. This is in ac- ligands. The cadmium cations are linked by pairs of μ-1,3
cordance with a search in the CCDC database, which shows bridging thiocyanato anions into chains, in which the thiocyan-
that in compounds with hard metals like e.g. Mn, Fe, Co, and ato anions are either all-trans, all-cis- or cis-cis-trans coordi-
Ni the bridging coordination is unfavored and therefore, less nated (Scheme 1).
compounds are reported with some selected examples given in
the reference list.[5–14] However, we have found that the μ-1,3-
bridging compound can be prepared by thermal decomposition
of precursors, in which the anions are only terminal N-bonded
and in which a part of the neutral N-donor co-ligands are re-
moved.[15–18] Unfortunately, by this procedure only microcrys-
talline products are obtained and therefore, structural infor-
mation is difficult to extract. However, in these cases the μ-
1,3-bridging compounds based on cadmium can be crystallized
from solution, which are more stable because of the chalco-
philicity of this cation. In those cases, where they are isotypic
* Prof. Dr. C. Näther
Fax: +49-431-8801520
E-Mail: cnaether@ac.uni-kiel.de
[a] Institut für Anorganische Chemie
Christian-Albrechts-Universität zu Kiel
Scheme 1. Arrangement of the thiocyanato anions in the three struc-
Max-Eyth-Straße 2
24118 Kiel, Germany
tures of [Cd(NCS)2(pyridine)2]n.[22]
Z. Anorg. Allg. Chem. 2013, 639, (2), 385–391
© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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S. Wöhlert, I. Jess, C. Näther
ARTICLE
The all-trans compound is metastable and can only be pre-
pared by thermal decomposition of Cd(NCS)2(pyridine)4. In
solution it converts into the thermodynamic stable cis-cis-trans
compound via the metastable all-cis modification as intermedi-
ate. Finally, if less pyridine is used in the synthesis, a 1:1 com-
pound of composition [Cd(NCS)2(pyridine)]n is obtained.
Based on these results we decided to investigate compounds
based on other pyridine derivatives and in the beginning we
used 4-ethylpyridine as co-ligand. Within these investigations
we obtained three compounds of different composition but we
have found no hints for the formation of different modifica-
tions. Herein we report on our results.
Results and Discussion
Crystal Structure of Cd(NCS)2(4-ethylpyridine)4 (1)
Figure 1. Experimental XRPD pattern of compound 1 (A) and XRPD
pattern of 1 calculated from single-crystal data (B).
If an excess of 4-ethylpyridine is used in the synthesis the
1:4 compound Cd(NCS)2(4-ethylpyridine)4 is obtained as a
phase pure material (Figure 1). This compound crystallizes in
Table 1. Selected bond lengths /Å for compound 1.
¯
the triclinic space group P1 with four formula units in the unit
Cd(1)–N(1)
2.315(3)
2.273(3)
2.367(3)
2.353(3)
2.408(3)
2.385(3)
Cd(2)–N(3)
Cd(2)–N(50)
Cd(2)–N(60)
Cd(3)–N(4)
Cd(3)–N(70)
Cd(3)–N(80)
2.282(3)
2.396(4)
2.377(3)
2.283(3)
2.390(4)
2.390(3)
cell (Table 5). The asymmetric unit consists of three crystallo- Cd(1)–N(2)
Cd(1)–N(10)
graphically independent discrete complexes, with two of them
Cd(1)–N(20)
located on centers of inversion. In each of the three complexes
Cd(1)–N(30)
the cadmium(II) cations are coordinated by two terminal N-
Cd(1)–N(40)
bonded thiocyanato anions and four 4-ethylpyridine ligands
within slightly distorted octahedra (Table 1 and Figure 2). The
values of the bond lengths and angles in all three complexes
are comparable and as expected the Cd–N bond lengths to the
negatively charged thiocyanato anions are significantly shorter
than those to the neutral 4-ethylpyridine ligands (Table 1).
Interestingly, in all three complexes a large deviation of the
Cd–N–C bond angles from linearity is observed [Cd1–N1–C1
=
145.9(3)°, Cd1–N2–C2 = 151.0(3)°, Cd2–N3–C3 =
154.0(3)°, and Cd3–N4–C4 = 159.0(3)°]. Significant differ-
ences in all complexes are predominantly found in the confor-
mation of the ethyl substituent.
Crystal Structure of [Cd(NCS)2(4-ethylpyridine)2]n (2)
Crystals of the 1:2 compound [Cd(NCS)2(4-ethyl-
pyridine)2]n (2) were obtained by the reaction of stoichiometric
amounts of Cd(NCS)2 and 4-ethylpyridine but can also be ob-
tained by thermal decomposition of compound 1 (see below).
This compound crystallizes in the centrosymmetric space
group P21/c with two formula units in the unit cell (Table 5).
The asymmetric unit consists of one cadmium(II) cation lo-
cated on a center of inversion, as well as of one thiocyanato
anion and one 4-ethylpyridine ligand in general positions. The
cadmium(II) cations are coordinated by two N-bonded and two
S-bonded thiocyanato anions as well as two N-bonded 4-ethyl-
pyridine ligands, all of them are trans-oriented. The CdN4S2
octahedra are slightly distorted with distances in the range of
2.290(3) Å to 2.7622(8) Å and angles between 87.33(7)° and
92.67(7)° and of 180° (Figure 3 and Table 2).
Figure 2. ORTEP plot of one of the three crystallographic independent
complexes in 1 as a representative with labeling and displacement el-
lipsoid drawn at the 50% probability level.
elongate in the direction of the crystallographic b axis (Fig-
ure 4). Neighboring chains are arranged in order that the aro-
matic rings are coplanar oriented indicating for π···π interac-
tions.
Crystal Structure of [Cd(NCS)2(4-ethylpyridine)]n (3)
In the crystal structure, the cadmium(II) cations are linked
Single-crystals suitable for structure determination of a li-
via μ-1,3-bridging thiocyanato anions into chains, which gand-deficient 1:1 compound [Cd(NCS)2(4-ethylpyridine)]n
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Z. Anorg. Allg. Chem. 2013, 385–391

Coordination Compounds Based on Cd(NCS)2(4-Ethylpyridine)x
Figure 5. ORTEP plot of compound 3 with labeling and displacement
ellipsoids drawn at the 50% probability level. Symmetry codes: A =
x, y + 1, z; B = –x, –y + 2, –z + 1.
Figure 3. ORTEP plot of compound 2 with labeling and displacement
ellipsoids drawn at the 50% probability level. Symmetry codes:
A = –x + 1, –y, –z + 1; B = –x, –y, –z + 1; C = x + 1, y, z.
Table 3. Selected bond lengths /Å for compound 3. Symmetry codes:
A = x, y – 1, z; B = –x + 1, –y + 2, –z + 1.
Cd(1)–N(1A)
Cd(1)–S(2B)
Cd(1)–S(2A)
Cd(1)–N(2)
Cd(1)–N(10)
Cd(1)–S(1)
N(1A)–Cd(1)–N(2) 168.9(1)
N(1A)–Cd(1)–N(10) 91.4(1)
N(2)–Cd(1)–N(10)
2.259(2)
2.779(1)
2.904(1)
2.288(2)
2.325(2)
N(2)–Cd(1)–S(1)
N(2)–Cd(1)–S(2A)
N(10)–Cd(1)–S(2A)
S(1)–Cd(1)–S(2A)
N(10)–Cd(1)–S(1)
97.6(1)
82.0(1)
84.6(1)
177.4(1)
97.9(1)
90.6(1)
167.8(1)
93.7(1)
Table 2. Selected bond lengths /Å for compound 2. Symmetry codes:
A = –x + 1, –y, –z + 1; B = –x, –y, –z + 1.
Cd(1)–N(1)
2.290(3)
2.366(3)
2.762(1)
90.1(1)
N(1)–Cd(1)–S(1B)
N(1A)–Cd(1)–N(10) 89.9(1)
N(10)–Cd(1)–S(1B) 89.6(1)
N(10A)–Cd(1)–S(1B) 90.4(1)
92.7(1)
Cd(1)–N(10)
Cd(1)–S(1B)
N(1)–Cd(1)–N(10)
2.6403(7) N(2)–Cd(1)–S(2B)
N(10)–Cd(1)–S(2B)
S(1)–Cd(1)–S(2B)
N(1A)–Cd(1)–S(2A) 87.65(6)
S(2B)–Cd(1)–S(2A) 83.81(2)
N(1A)–Cd(1)–S(1B) 87.3(1)
91.5(1)
N(1A)–Cd(1)–S(1) 92.6(1)
N(1A)–Cd(1)–S(2B) 84.35(6)
Two neighboring octahedra are connected by pairs of μ-
1,1,3(S,S,N)-coordinating thiocyanato anions into dimers,
which are further connected via μ-1,3(N,S) and the μ-1,1,3-
(S,S,N)-bridging thiocyanato anions into double chains, which
elongate in the direction of the crystallographic a axis (Fig-
ure 6, Figure 7).
Figure 4. Crystal structure of [Cd(NCS)2(4-ethylpyridine)2]n (2) with
view along the crystallographic b axis.
(3) can be synthesized by an excess of cadmium(II) thio-
cyanate with 4-ethylpyridine. This compound 3 crystallizes in
the centrosymmetric space group P21/n with all atoms in a
general position (Table 5). In the crystal structure each cad-
mium(II) cation is coordinated by two N-bonded and three S-
bonded thiocyanato anions as well as one 4-ethylpyridine li-
gand in a slightly distorted octahedral arrangement (Figure 5,
Table 3).
Figure 6. Crystal structure of [Cd(NCS)2(4-ethylpyridine)]n (3) with
view along the crystallographic a axis.
Z. Anorg. Allg. Chem. 2013, 385–391
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387

S. Wöhlert, I. Jess, C. Näther
ARTICLE
Figure 7. Experimental XRPD pattern of compound 3 (A) and XRPD
pattern of 3 calculated from single-crystal data (B).
Thermoanalytical Investigations
In order to investigate if compounds 2 and 3 can also be
obtained by thermal decomposition, the 4-ethylpyridine-rich
1:4 compound 1 was investigated for their thermal properties.
In this context the question raises if the same modification is
found by thermal decomposition as it can be obtained from
solution. On heating of compound 1 in a thermobalance to
300 °C, three mass steps are observed in the TG curve that
were accompanied with endothermic events in the DTA curve
(Figure 8). From the DTG curve it is obvious that the first
mass step is well, all others poorly resolved. The experimental
mass loss of Δm(exp) = 32.4% in the first step and of Δm(exp)
= 15.9% in the second step are in good agreement with the
removal of two 4-ethylpyridine ligands in the first and one 4-
ethylpyridine ligand (Δm(calcd.) = 16.3%) in the second step.
To verify the nature of the intermediates additional TG experi-
ments were performed and stopped after the first and second
TG step. Elemental analysis of the residue obtained after the
first TG step yielded a composition of Cd(NCS)2(4-ethylpyr-
idine)2 (see Experimental Section). XRPD investigations of the
residue prove that compound 2 is obtained (Figure 9). Ad-
ditional XRPD investigations of the residue obtained after the
second TG step shows that it is amorphous against X-ray.
Figure 8. DTG, TG and DTA curves of compound 1. Heating rate =
1 K·min–1; given are the peak temperatures TP in °C and the mass loss
in%.
Figure 9. Experimental XRPD pattern of compound 2 obtained from
solution (A) and XRPD pattern of the residue obtained after the first
TG step in the thermal decomposition reaction of compound 1 (B) and
XRPD pattern calculated from single-crystal data for compound 2 (C).
Infrared Spectroscopic Investigations
The coordination mode of the thiocyanato anions was ad-
ditionally investigated by IR spectroscopic investigations by
analyzing the asymmetric stretching vibration νas(CN) of the
thiocyanato anions. According to the literature for terminal N- more detail all compounds were investigated by IR spec-
bonded thiocyanato anions the asymmetric stretching vibration troscopy. However, from these investigations it is obvious that
is found at about 2050 cm–1, whereas for μ-1,3-(N,S)-bridging in this case only small deviations are found from the values
thiocyanato anions this value shifted to about 2100 cm–1. Fi- given in literature and that these values are comparable to
nally, if μ-1,1-(N,N)-bridging anions are present this vibration those obtained for the corresponding cadmium thiocyanato co-
is observed below 2050 cm–1.[23,24] However, we have found ordination compounds based on pyridine as co-ligand
that all these values depend strongly on the nature of the metal (Table 4). Moreover, from these investigations it is also obvi-
cation and the co-ligand and therefore, can overlap for the dif- ous that νas(CN) is shifted by about 20 cm–1 to higher values
ferent coordination modes. To investigate this dependence in if μ-1,1,3-[S,S,N)-coordinating anions are present.
388
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Z. Anorg. Allg. Chem. 2013, 385–391

Coordination Compounds Based on Cd(NCS)2(4-Ethylpyridine)x
Table 4. Values of the asymmetric stretching vibration νas(CN) in com-
pounds 1, 2 and 3 as well as for the corresponding pyridine compounds
Experimental Section
retrieved from literature.[22]
.
Synthesis: CdSO4·8/3H2O, Ba(NCS)2·3H2O, and 4-ethylpyridine were
obtained from Alfa Aesar. All chemicals were used without further
purification. Cd(NCS)2 was prepared by a reaction of equimolar
amounts of CdSO4·8/3H2O and Ba(NCS)2·3H2O in water. The re-
sulting precipitate of BaSO4 was filtered off and the filtrate was con-
centrated to complete dryness resulting in a white residue of
Cd(NCS)2. The purity was checked by XRPD and elemental analysis.
Compound
νas(CN) /cm–1 Coordination
Cd(NCS)2(4-ethylpyridine)4 (1)
[Cd(NCS)2(4-ethylpyridine)2]n (2)
[Cd(NCS)2(4-ethylpyridine)]n (3)
Cd(NCS)2(pyridine)4
[Cd(NCS)2(pyridine)2]n all-trans
[Cd(NCS)2(pyridine)2]n all-cis
2037
2102
2124, 2107
2054
2093
terminal
μ-1,3
μ-1,1,3
terminal
μ-1,3
2089, 2107
μ-1,3
Synthesis of [Tetrakis(4-ethylpyridine-κN)-bis(thiocyanato-κN)-
cadmium(II)] (1): Colorless block-shaped single crystals suitable for
X-ray structure determination were obtained by
[Cd(NCS)2(pyridine)2]n cis-cis-trans 2089
μ-1,3
[Cd(NCS)2(pyridine)]n
2120, 2105
μ-1,1,3
a reaction of
Cd(NCS)2 (68.6 mg, 0.30 mmol) with an excess of 4-ethylpyridine in
a closed test tube at 120 °C. Colorless block-shaped single-crystals
were obtained on cooling after 3 d.
Investigations on the Stability of Compound 2
A
white crystalline powder was obtained by the reaction of
As mentioned in the introduction, for [Cd(NCS)2-
(pyridine)2]n three different modifications are found, that differ
in the coordination mode of the anionic ligands. The all-trans
form was obtained by thermal decomposition and transform
into solution within hours into the cis-cis-trans form via the
all-cis form as an intermediate, which proves that the latter
represents the thermodynamic stable form at room tempera-
ture. In this context it is noted that the all-trans form of
[Cd(NCS)2(4-ethylpyridine)2]n is also obtained by thermal de-
composition, but in contrast to pyridine this form is also ob-
tained from the liquid phase. At first sight this is not surpris-
ing, because if this compound would be metastable it is usually
being observed in the beginning. However, if the formation of
compound 2 is followed in solution there are no indications
that it will transform within a short period into a new modifica-
tion. Unfortunately, it was observed that this compound trans-
forms slowly into the 4-ethylpyridine-rich compound 1, which
seems to be more stable and which prevent to follow this reac-
tion for a longer time. Additional DSC investigations gave also
no hints that additional forms are present and therefore, it can-
not be answered if compound 2 represent the stable form or if
other modifications will exist.
Cd(NCS)2 (343 mg, 1.50 mmol) with an excess of 4-ethylpyridine by
stirring the reactants at 120 °C in a closed test tube. The residues were
filtered off and washed with water and diethyl ether and dried in air.
Yield based on Cd(NCS)2: 969 mg (98.4%). C30H36CdN6S2 (657.18):
calcd. C 54.83, H 5.52, N 12.79, S 9.76%; found C 55.16, H 5.45, N
12.81, S 10.47%. IR (ATR): ν˜ = 2969 (w), 2931 (w), 2873 (w), 2037
(s), 1609 (s), 1556 (m), 1499 (w), 1454 (m), 1421 (m), 1375 (w), 1317
(w), 1220 (m), 1107 (w), 1066 (w), 1013 (m), 971 (w), 877 (w), 827
(s), 783 (m), 571 (m), 501 (m) cm–1.
Synthesis of Catena-poly[bis(4-ethylpyridine-κN)-bis(thiocyanato-
κN,S)-cadmium(II)] (2): Colorless block-shaped single crystals suit-
able for X-ray structure determination were obtained by a reaction of
Cd(NCS)2 (34.3 mg, 0.15 mmol) and 4-ethylpyridine (34.1 μL,
0.30 mmol) in water (1 mL) in a snap-vial at room temperature after
1 week.
A
white crystalline powder was obtained by the reaction of
Cd(NCS)2 (343 mg, 1.50 mmol) and 4-ethylpyridine (341 μL,
3.0 mmol) by stirring the reactants in water (3 mL) for 3 d at room
temperature. The residues were filtered off and washed with water and
diethyl ether and dried in air. Yield based on Cd(NCS)2: 639 mg
(96.3%). C16H18CdN4S2 (442.87): calcd. C 43.39, H 4.10, N 12.65, S
14.48%; found C 42.96, H 3.70, N 12.47, S 13.87%. IR (ATR): ν˜ =
2969 (w), 2931 (w), 2872 (w), 2102 (s), 1611 (s), 1556 (m), 1501 (m),
1455 (m), 1421 (m), 1375 (w), 1224 (m), 1108 (w), 1070 (m), 1015
(m), 981 (w), 932 (w), 819 (s), 785 (m), 567 (m), 504 (m), 463 (m)
cm–1.
Conclusions
Three new cadmium thiocyanato coordination polymers
with 4-ethylpyridine were presented, that exhibit the same
composition and same coordination topology as those for
pyridine reported recently.[22] In contrast to [Cd(NCS)2-
(pyridine)2]n only one modification was observed for
[Cd(NCS)2(4-ethylpyridine)2]n, in which the anionic ligands
are always trans-configured. This is the most common motive
in this class of compounds and observed in several other μ-
1,3-(N,S)-bridging compounds.[3,10,11,13] However, during our
investigations we have found a more ligand-deficient com-
pound of composition [Cd(NCS)2(4-ethylpyridine)]n, which
normally cannot be obtained with other transition metals like
Mn, Fe, Co, and Ni because of their relatively low chalcophil-
icity. This compound exhibits a more condensed coordination
network, which is very rare and which was observed only in a
few compounds.[22,25]
Synthesis of Catena-poly[(4-ethylpyridine-κN)-(bis-thiocyanato-
kN,S)-(tris-thiocyanato-κN,S,S)-cadmium(II)] (3): Single crystals
suitable for X-ray structure determination were obtained by a reaction
of Cd(NCS)2 (137 mg, 0.6 mmol) and 4-ethylpyridine (17.1 μL,
0.15 mmol) in ethanol (1 mL) in a snap-vial at room temperature. Col-
orless block-shaped single-crystals were obtained after 3 d.
A white crystalline powder was obtained by the reaction of Cd(NCS)2
(411 mg, 1.8 mmol) and 4-ethylpyridine (51.3 μL, 0.45 mmol) in 3 mL
ethanol, by stirring the reactants in solution for 3 d at room tempera-
ture. The residues were filtered off and washed with water and diethyl
ether and dried in air. Yield based on Cd(NCS)2: 147 mg (97.5%).
C9H9CdN3S2 (335.72): calcd. C 32.20, H 2.70, N 12.52, S 19.10%;
found C 32.31, H 2.81, N 12.51, S 18.63%. IR (ATR): ν˜ = 2977 (w),
2134 (s), 2124 (s), 2107 (s), 1615 (s), 1556 (w), 1504 (w), 1428 (m),
1227 (m), 1068 (w), 1021 (m), 828 (s), 786 (m), 569 (m), 447 (m)
cm–1.
Z. Anorg. Allg. Chem. 2013, 385–391
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S. Wöhlert, I. Jess, C. Näther
ARTICLE
Table 5. Selected crystal data and details on the structure determinations from single crystal data for compound Cd(NCS)2(4-ethylpyridine)4 (1),
[Cd(NCS)2(4-ethylpyridine)2]n (2), and [Cd(NCS)2(4-ethylpyridine)]n (3).
1
2
3
Formula
C30H36CdN6S2
657.17
C16H18CdN4S2
442.86
monoclinic
P21/c
5.8913(5)
18.3943(16)
8.5953(8)
90
96.5420(10)
90
C9H9CdN3S2
335.71
monoclinic
P21/n
13.8186(6)
5.81020(10)
15.5742(7)
90
91.153(3)
90
MW /g·mol–1
Crystal system
Space group
a /Å
triclinic
¯
P1
11.5997(10)
16.3699(12)
18.7395(14)
72.712(8)
75.252(9)
76.458(9)
0.19ϫ0.12ϫ0.08
3236.9(4)
293
b /Å
c /Å
α /°
β /°
γ /°
Crystal size /mm
0.12ϫ0.09ϫ0.07
925.38(14)
200
0.12ϫ0.10ϫ0.08
1250.18(8)
293
V /Å3
T /K
Z
4
2
4
Dcalc /mg·m–3
1.349
0.832
1.589
1.409
1.784
2.052
μ /mm–1
θmax /°
28.06
27.96
27.50
Reflections collected
Unique reflections
Tmin / Tmax
Rint
42893
15164
0.7793 / 0.8922
0.0395
9733
2196
0.7654 / 0.8472
0.0517
19807
2888
0.6883 / 0.7611
0.0256
Refl. [Fo Ͼ 4σ(Fo)]
Parameters
R1 [Fo Ͼ 4σ(Fo)]
wR2
11478
720
0.0485
0.1362
1768
107
0.0387
0.0975
2529
136
0.0253
0.0522
GOF
1.033
0.91 / –0.72
1.021
0.95 / –1.16
1.112
0.40 / –0.42
Δρmax/min /e·Å–3
Single Crystal Structure Analysis: The data collection was per-
formed with an imaging plate diffraction system: STOE IPDS-1 for 2
and STOE IPDS-2 for 1 and 3 using Mo-Kα radiation. The structure
solution was done with direct methods using SHELXS-97 and struc-
ture refinement was performed against F2 using SHELXL-97.[26] Nu-
X-ray Powder Diffraction (XRPD): XRPD experiments were per-
formed with a Stoe Transmission Powder Diffraction System (STADI
P) with Cu-Kα-radiation (λ = 154.0598 pm) that is equipped with a
linear position-sensitive detector (Delta 2θ = 6.5–7° simultaneous; scan
range overall = 2–130°) from STOE & CIE and an Image Plate Detec-
merical absorption correction was applied using X-red and X-shape of tor (scan range overall = 0–127°).
the Program Package X-area.[27,28] All non-hydrogen atoms were re-
fined with anisotropic displacement parameters. All hydrogen atoms
were positioned with idealized geometry and were refined isotropic
Acknowledgements
with Uiso(H) = –1.2Ueq(C) using a riding model with dC–H = 0.93 Å
This project was supported by the Deutsche Forschungsgemeinschaft
for 1 and 3 and dC–H = 0.95 Å for 2. In compound 1 one ethyl group is
disordered and was refined using a split model. Details of the structure
determination are given in Table 5.
(Project No. NA 720/3–1) and the State of Schleswig-Holstein. We
thank Professor Dr. Wolfgang Bensch for access to his experimental
facility.
Crystallographic data (excluding structure factors) for the structures in
this paper have been deposited with the Cambridge Crystallographic
Data Centre, CCDC, 12 Union Road, Cambridge CB21EZ, UK. Copies
of the data can be obtained free of charge on quoting the depository
numbers CCDC-908581 (1), CCDC-908582 (2), and CCDC-908583
(3) (Fax: +44-1223-336-033; E-Mail: deposit@ccdc.cam.ac.uk,
http://www.ccdc.cam.ac.uk)
References
[1] J. Boeckmann, C. Näther, Dalton Trans. 2010, 39, 11019.
[2] J. Boeckmann, M. Wriedt, C. Näther, Chem. Eur. J. 2012, 18,
5284.
[3] J. Boeckmann, C. Näther, Polyhedron 2012, 31, 587.
[4] S. Wöhlert, J. Boeckmann, M. Wriedt, C. Näther, Angew. Chem.
Int. Ed. 2011, 50, 6920.
[5] F. H. Allen, S. Bellard, M. D. Brice, B. A. Cartwright, A.
Doubleday, H. Higgs, T. Hummelink, B. G. Hummelink-Peters,
O. Kennard, W. D. S. Motherwell, J. R. Rodgers, D. G. Watson,
Acta Crystallogr. Sect. B 1979, 35, 2331.
[6] H. Cai, Y. Guo, Y. Li, J.-G. Li, Acta Crystallogr. Sect. A 2007,
63, m936.
[7] R. Sekiya, S. Nishikiori, K. Ogura, Chem. Lett. 2006, 35, 614.
[8] R. Sekiya, S.-i. Nishikiori, Chem. Commun. 2012, 48, 5022.
[9] R. Sekiya, S.-i. Nishikiori, Cryst. Eng. Commun. 2011, 13, 6405.
[10] R. Sekiya, S.-i. Nishikiori, R. Kuroda, Cryst. Eng. Commun.
2009, 11, 2251.
Spectroscopy: IR spectra were recorded with an Alpha IR spectrome-
ter from Bruker equipped with a Platinum ATR QuickSnapTM sam-
pling module between 4000–375 cm–1.
Elemental Analysis: CHNS analysis was performed with an EURO
EA elemental analyzer, fabricated by EURO VECTOR Instruments
and Software.
Differential Scanning Calorimetry: The DSC experiments were per-
formed with a DSC 1 Star System with STARe Excellence Software
from Mettler-Toledo AG.
390
www.zaac.wiley-vch.de
© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Z. Anorg. Allg. Chem. 2013, 385–391

Coordination Compounds Based on Cd(NCS)2(4-Ethylpyridine)x
[11] D. Vujovic, H. G. Raubenheimer, L. R. Nassimbeni, Dalton
Trans. 2003, 631.
[12] S. Banerjee, B. Wu, P.-G. Lassahn, C. Janiak, A. Ghosh, Inorg.
[21] I. Jeß, J. Boeckmann, C. Näther, Dalton Trans. 2012, 41, 228.
[22] S. Wöhlert, J. Boeckmann, I. Jess, C. Näther, Cryst. Eng. Com-
mun. 2012, 14, 5412.
[23] R. A. Bailey, S. L. Kozak, T. W. Michelsen, W. N. Mills, Coord.
Chem. Rev. 1971, 6, 407.
[24] R. J. H. Clark, C. S. Williams, Spectrochim. Acta 1966, 22, 1081.
[25] Z. Yu, K. Yu, L. Lai, K. A. Udachin, H. Zhu, J. Tao, X. You, M.
Strobele, H. J. Meyer, J. A. Ripmeester, Chem. Commun. 2004,
6, 648.
[26] G. M. Sheldrick, Acta Crystallogr., Sect. A 2008, 64, 112.
[27] X-Red, Version 1.11, Program for Data Reduction and Absorption
Correction, STOE & CIE GmbH, Darmstadt, Germany, 1998.
[28] X-Shape, Version 1.03, Program for the Crystal Optimization for
Numerical Absorption Correction, STOE & CIE GmbH, Darm-
stadt, Germany, 1998.
Chim. Acta 2005, 358, 535.
[13] M. G. Barandika, M. L. Hernandez-Pino, M. K. Urtiaga, R. Cor-
tes, L. Lezama, M. I. Arriortua, T. Rojo, J. Chem. Soc. Dalton
Trans. 2000, 1469.
[14] J. M. Shi, J. N. Chen, C. J. Wu, J. P. Ma, J. Coord. Chem. 2007,
60, 2009.
[15] C. Näther, J. Greve, J. Solid State Chem. 2003, 176, 259.
[16] M. Wriedt, I. Jeß, C. Näther, Eur. J. Inorg. Chem. 2009, 1406.
[17] M. Wriedt, S. Sellmer, C. Näther, Inorg. Chem. 2009, 48, 6896.
[18] M. Wriedt, S. Sellmer, C. Näther, Dalton Trans. 2009, 7975.
[19] J. Boeckmann, I. Jeß, T. Reinert, C. Näther, Eur. J. Inorg. Chem.
2011, 2011, 5502.
[20] J. Boeckmann, T. Reinert, C. Näther, Z. Anorg. Allg. Chem. 2011,
637, 940.
Received: November 1, 2012
Published Online: January 31, 2013
Z. Anorg. Allg. Chem. 2013, 385–391
© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
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