Synthesis and crystal structure of a copper(II) 5-sulfosalicylate complex with thiosemicarbazide

Article abstract of DOI:10.1134/S003602361204002X

The compound [Cu(TSC)₂](H₂SSal)₂ (I) has been synthesized (TSC is thiosemicarbazide, H₃SSal is 5-sulfosalicylic acid) and studied by IR spectroscopy and X-ray crystallography. The crystals of I are triclinic: a = 6.728(2) ?, b = 7 1 .772(1) ?, c = 11.600(6) ?, a = 88.60°, β = 86.68(3)°, y = 79.22(4)°, V = 594.8(4) ?³, Z = 2, space group P. The structural units of the crystal are the centrosymmetric [Cu(TSC) ₂]²⁺ cation, in which the Cu atom is in a square-planar coordination formed by the bidentate chelating (N,S) TSC ligands, and (H ₂SSal)- anions (Cu(1)-N(3), 2.013(3) ?; Cu(1)-S(1), 2.275(1) ?; intrachelate angle, 86.8°). The coordination polyhedron of the Cu(1) atom is completed to a prolate tetragonal bipyramid (4 + 2) by Cu-O bonds (2.810(3) ?) of the sulfate moieties of both anions, which form together with hydrogen bonds the [Cu(TSC)₂(H₂SSal)₂] supermolecule. The complex cations are packed in layers and alternate with anion-containing layers. Hydrogen bonding and n-n stacking interactions are responsible for formation of supramolecular layer ensembles.

Full text of DOI:10.1134/S003602361204002X

ISSN 0036ꢀ0236, Russian Journal of Inorganic Chemistry, 2012, Vol. 57, No. 4, pp. 508–514. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © A.S. Antsyshkina, G.G. Sadikov, T.V. Koksharova, V.S. Sergienko, S.V. Kurando, 2012, published in Zhurnal Neorganicheskoi Khimii, 2012, Vol. 57,
No. 4, pp. 570–576.
COORDINATION COMPOUNDS
Synthesis and Crystal Structure of a Copper(II) 5ꢀSulfosalicylate
Complex with Thiosemicarbazide
A. S. Antsyshkinaa, G. G. Sadikova, T. V. Koksharovab, V. S. Sergienkoa, and S. V. Kurandob
a Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences,
Leninskii pr. 31, Moscow, 119991 Russia
b Mechnikov National University, Dvoryanskaya ul. 2, Odessa, 65026 Ukraine
eꢀmail:antas@igic.ras.ru
Received December 28, 2010
Abstract—The compound [Cu(TSC)2](H2SSal)2
(I) has been synthesized (TSC is thiosemicarbazide,
H3SSal is 5ꢀsulfosalicylic acid) and studied by IR spectroscopy and Xꢀray crystallography. The crystals of
I
are triclinic:
594.8(4) Å3,
a
Z
= 6.728(2) Å,
= 2, space group
b
= 7.772(1) Å,
P
c
= 11.600(6) Å,
α
= 88.60°,
β
= 86.68(3)°,
γ
= 79.22(4)°, V =
1. The structural units of the crystal are the centrosymmetric [Cu(TSC)2]2+
cation, in which the Cu atom is in a squareꢀplanar coordination formed by the bidentate chelating (N,S) TSC
ligands, and (H2SSal)– anions (Cu(1)–N(3), 2.013(3) Å; Cu(1)–S(1), 2.275(1) Å; intrachelate angle, 86.8°).
The coordination polyhedron of the Cu(1) atom is completed to a prolate tetragonal bipyramid (4 + 2) by
Cu–O bonds (2.810(3) Å) of the sulfate moieties of both anions, which form together with hydrogen bonds
the [Cu(TSC)2(H2SSal)2] supermolecule. The complex cations are packed in layers and alternate with anionꢀ
containing layers. Hydrogen bonding and
supramolecular layer ensembles.
π
–π
stacking interactions are responsible for formation of
DOI: 10.1134/S003602361204002X
Our results of studying Ni(II) and Cu(II) bis(thioꢀ
Depending on the degree of deprotonation of
semicarbazide) complexes with different anions [1, 2] H3SSal, there are H2SSal–, HSSal2–, and SSal3–
and available literature data on the structures of analꢀ anions. Incomplete deprotonation is possible for difꢀ
– 1
ogous compounds [3–9] have revealed a considerable ferent combination of atoms in [H3 SSal]n
.
n
variety of the structures of these compounds in spite of
a rather stereotypic structure of the complex cation.
The [М(TSC)2]2+ cation (M = Ni(II), Cu(II)) in taining the monodeprotonated anion.
these compounds has a square of nearꢀsquare shape
In this paper, we report the results of Xꢀray crystalꢀ
, conꢀ
lographic analysis of [Cu(TSC)2](H2SSal)2 (I)
owing to the bidentate chelating (N,S) coordination
of the TSC ligand. Sometimes, the metal coordination
EXPERIMENTAL
sphere is completed to tetragonalꢀpyramidal or tetraꢀ
gonalꢀbipyramidal by axial atoms at elongated disꢀ
tances. The metal atom is in the plane of the coordinaꢀ
tion square. The TSC ligand is planar, but its plane can
be somewhat out of the coordination plane. In this
case, there is a small bend along the N···S line (an
envelope conformation). The linear and angular
parameters of the coordination polyhedron are almost
identical for the same metal but are somewhat differꢀ
ent for Ni(II) and Cu(II).
Synthesis of I (С8H10Cu0.5N3O6S2)
beakers, solutions of 1.71 g CuCl2 2H2O (0.01 mol)
. In separate
⋅
and 0.4 g NaOH (0.01 mol) in 5 mL water were preꢀ
pared and then poured together. The resulting precipꢀ
itate was filtered off on a paper filter, washed with
water, and added portionwise to a solution of 2.18 g
5ꢀsulfosalicylic acid (0.01 mol) in 5 mL water. To the
resulting solution of copper(II) 5ꢀsulfosalicylate, 1.82 g
(0.02 mol) of dry finely ground thiosemicarbazide was
added, which was accompanied by formation of a
brown precipitate. It was stirred for 15 min with a magꢀ
netic stirrer, filtered off through a Schott filter, washed
It is worth noting that a considerable role in crystal
structure is played by the anion mainly involved in forꢀ
mation of the supramolecular crystal architecture.
with water, and dried at 50 С to a constant weight.
°
Crystals suitable for Xꢀray crystallography were
obtained by recrystallization of the powder product
from water.
The anion of multifunctional 5ꢀsulfosalicylic acid
H3SSal) used in this work favors the formation of
numerous hydrogen bonds, which can be combined in
cyclic fragments capable of strengthening of the strucꢀ
(
The IR absorption spectra were recorded as KBr pelꢀ
ture due to
π–π
stacking interaction.
lets on a Shimadzu FTIRꢀ8400S spectrophotometer.
508

SYNTHESIS AND CRYSTAL STRUCTURE
509
Table 1. Crystallographic parameters and experimental details for compound
I
Empirical formula
FW
C H Cu N O S
8 10 0.50 3 6 2
340.08
Color, habit
Crystal size, mm
Violet, prisms
0.20
×
0.18
293
×
0.15
T
, K
Crystal symmetry
Space group
Triclinic
P1
Unit cell parameters
a
, Å
, Å
, Å
, deg
, deg
6.728(2)
7.772(1)
11.600(6)
88.60(3)
86.68(3)
79.22(3)
594.8(4)
2
b
c
α
β
γ, deg
3
V
Z
, Å
ρcalc, g/cm3
1.899
–1
μ, cm
5.294
F(000)
347
Scan range
3.82–65.93
1, –8 8, –13
2190
Index range
7
≤
h
≤
≤
k
≤
≤
l ≤ 13
Total number of measured reflections
Number of unique reflections
2000 [R
(int) = 0.0181]
1897
Number of reflections with
Correction for absorption
I
> 2σ(I)
Not introduced
218
Not introduced
2
GOOF on
F
1.047
R
R
[
I
> 2
σ
(
I
)]
R
R
1 = 0.0504, wR2 = 0.1400
1 = 0.0532, wR2 = 0.1429
0.938 and –1.156
(for all reflections)
3
Δρ
and Δρ , e/Å
min
max
Xꢀray diffraction. Experimental reflection intensities method. The hydrogen atoms were located from differꢀ
were collected on an EnrafꢀNonius Cadꢀ4 diffractometer ence Fourier syntheses and refined with an individual
(Cu
К
radiation, graphite monochromator) using
θ
/2
θ
isotropic temperature parameter. Calculations were perꢀ
α
scan mode. The structure was solved by the heavyꢀatom formed with the SHELXLꢀ93 program package [10].
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 57 No. 4 2012

510
ANTSYSHKINA et al.
Table 2. Atomic coordinates and Ueq
/
U
iso (Å2
×
103) for compound
I
Atom
x
y
z
Ueq/Uiso
Cu(1)
S(1)
0
0
0
33(1)
35(1)
29(1)
38(1)
43(1)
38(1)
39(1)
56(1)
43(1)
41(1)
35(1)
32(1)
31(1)
28(1)
34(1)
32(1)
26(1)
28(1)
26(1)
30(1)
1307(1)
3551(1)
2177(1)
7304(1)
13308(3)
13447(4)
10197(4)
7562(4)
5468(4)
8249(4)
4993(4)
2830(4)
1143(4)
3413(4)
9625(4)
7842(5)
7156(5)
8216(4)
9998(4)
10722(4)
12596(4)
5440(56)
5542(72)
587(65)
3359(67)
1298(63)
14384(77)
11070(66)
7144(60)
5973(57)
10709(58)
780(1)
2137(1)
5821(2)
3895(2)
6825(2)
1707(2)
2307(2)
1439(2)
1622(3)
1146(3)
732(3)
S(2)
O(1)
1021(4)
O(2)
1115(5)
O(3)
2217(4)
O(4)
1530(4)
O(5)
4438(5)
O(6)
4872(4)
N(1)
N(2)
N(3)
C(1)
–1073(6)
–2696(5)
–2693(5)
–967(6)
2587(5)
1208(3)
5739(3)
5594(3)
4505(3)
3532(3)
3655(3)
4755(3)
4873(3)
1557(35)
1727(47)
1296(45)
1248(42)
134(46)
3968(46)
6784(41)
6214(41)
4446(34)
3007(40)
C(2)
C(3)
3318(5)
C(4)
3655(5)
C(5)
3281(5)
C(6)
2582(5)
C(7)
2229(4)
C(8)
1409(5)
H(1N1)
H(2N1)
H(1N3)
H(1N2)
H(2N3)
H(1)
H(2)
H(3)
H(4)
H(6)
48(68)
35(11)
57(15)
51(13)
42(13)
52(13)
56(15)
41(14)
45(11)
35(10)
42(11)
–2269(90)
–3128(74)
–3769(80)
–3432(78)
473(80)
1740(73)
3604(69)
3992(61)
2432(66)
Xꢀray diffraction experimental details, crystallographic in Table 2, and bond angles are listed in Table 3. These valꢀ
data, and refinement results are summarized in Table 1, ues were deposited with the Cambridge structural database
atomic coordinates and temperature factors are presented (CCDC no. 798530).
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 57 No. 4 2012

SYNTHESIS AND CRYSTAL STRUCTURE
511
RESULTS AND DISCUSSION
Table 3. Bond lengths (
pound
d
) and bond angles (
ω
) for comꢀ
I
Crystals of I are composed of doubly charged cenꢀ
trosymmetric [Cu(TSC)2]2+ cations and (Н2SSal)–
anions monodeprotonated at the sulfate moiety of
5ꢀsulfosalicylic acid.
Bond
d, Å
Cu(1)–N(3)
Cu(1)–S(1)
Cu(1)–O(4)
S(1)–C(1)
S(2)–O(5)
S(2)–O(4)
S(2)–O(6)
S(2)–C(5)
O(1)–C(8)
O(2)–C(8)
O(3)–C(2)
N(1)–C(1)
N(2)–C(1)
N(2)–N(3)
C(2)–C(3)
C(2)–C(7)
C(3)–C(4)
C(4)–C(5)
C(5)–C(6)
C(6)–C(7)
C(7)–C(8)
2.013(3)
2.275(1)
2.810(3)
1.702(4)
1.453(3)
1.452(3)
1.455(3)
1.769(3)
1.236(4)
1.305(4)
1.341(4)
1.317(5)
1.331(5)
1.406(4)
1.392(5)
1.412(5)
1.372(5)
1.388(5)
1.385(5)
1.397(4)
1.464(5)
As in other
3dꢀmetal bis(thiosemicarbazide) comꢀ
plexes, the copper atom in
I
is coordinated in the
bidentate chelating (N,S) mode by two TSC ligands,
which leads to closing of nearly flat ( 0.05 Å) fiveꢀ
membered chelate rings. The Cu(1)–N(3) and
Cu(1)–S(1) bond lengths are 2.013(3) and 2.275(1) Å,
respectively, and the intrachelate N(3)Cu(1)S(1)
angle id 86.8(1) . These values are also typical for
°
other compounds containing analogous cation [3–9].
The coordination square of the Cu atom is completed
to a prolate tetragonal bipyramid (4 + 2) by the
Cu(1)–L(4) bonds (2.810(3) Å). Hydrogen bonds
(table 4) combine the cation and anion into a neutral
[
Cu(TSC)2(Н2SSal)2] supermolecule, which in the
main building unit of the crystal (Fig. 1).
Supermolecules are closely packed in layers
formed, on the one hand, due a pair of symmetrically
located hydrogen bonds
[Cu(TSC)2]2+ cations into chain ensembles and, on
the other hand, due to stacking interactions
6
combining the
Angle
ω
, deg
π π
–
N(3)Cu(1)S(1)
S(1)Cu(1)O(4)
N(3)Cu(1)O(4)
C(1)S(1)Cu(1)
O(5)S(2)O(4)
O(5)S(2)O(6)
O(4)S(2)O(6)
O(5)S(2)C(5)
O(4)S(2)C(5)
O(6)S(2)C(5)
C(1)N(2)N(3)
N(2)N(3)Cu(1)
N(1)C(1)N(2)
N(1)C(1)S(1)
N(2)C(1)S(1)
O(3)C(2)C(3)
O(3)C(2)C(7)
C(3)C(2)C(7)
C(4)C(3)C(2)
C(3)C(4)C(5)
C(4)C(5)C(6)
C(4)C(5)S(2)
C(6)C(5)S(2)
C(5)C(6)C(7)
C(6)C(7)C(2)
C(6)C(7)C(8)
C(2)C(7)C(8)
O(1)C(8)O(2)
O(1)C(8)C(7)
O(2)C(8)C(7)
86.82(8)
92.69(6)
102.3(1)
95.79(12)
113.0(2)
112.8(2)
111.9(2)
105.1(2)
106.4(2)
106.9(2)
120.6(3)
113.3(2)
117.5(3)
120.7(3)
121.8(3)
117.2(3)
123.5(3)
119.3(3)
120.2(3)
121.0(3)
119.7(3)
120.8(3)
119.3(2)
120.1(3)
119.5(3)
119.5(3)
120.9(3)
122.9(3)
122.6(3)
114.5(3)
between the anionic parts of the supermolecules. In
both cases, cationic and anionic supramolecular
ensembles coupled to each other are formed in the
direction in the (010) plane (Fig. 2).
а
The (Н2SSal)– anion in
I contains the sulfate and
salicylate moieties bonded through the C(5) atom.
Hydrogen bond 2 closes a sixꢀmembered ring so that
the salicylate moiety transforms into two fused rings.
Both rings are involved in formation of
π
– stacking
π
ensembles (Fig. 3). The distance between stacking
planes is 3.51 Å. In addition, (Н2SSal)– anions are
combined by a centrosymmetric pair of hydrogen
bonds 1 into planar dimers, which, like bricks, form
wallsꢀlayers running through the entire crystal.
Parallel to the anionic layers in structure I, there
are layers of cationic cores of supermolecules linked
with each other not only through hydrogen bond 6 but
also through hydrogen bonds 4 and 5, involving the N
atoms of the thiosemicarbazide ligand and the O(4),
O(5), and O(6) atoms if the sulfate moieties of neighꢀ
boring supermolecules. Thus, the crystal contains
supramolecular layers ensembles oriented parallel to
the (001) crystallographic plane (Fig. 3). The figure
also shows the structure of adjacent anionic layers surꢀ
rounding the layer of cations. The arrows show bands
of planar dimeric anions running perpendicular to the
plane of the supramolecular ensemble (i.e., to the
plane of the figure). As a whole, joint efforts of hydroꢀ
gen bonds and electrostatic and
π
–π stacking interacꢀ
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 57 No. 4 2012

512
ANTSYSHKINA et al.
Table 4. Hydrogen bond geometry in structure
I
d
, Å
AHB angle,
deg
No.
A–H···B bond
B atom position
A···B
A–H
H···B
1
2
3
4
5
6
7
8
O(2)–H(1)···O(1)
2.676(4)
2.663(4)
2.898(5)
3.035(6)
2.845(5)
3.090(4)
2.971(4)
3.774(3)
0.78(6)
0.70(5)
0.89(5)
0.84(6)
0.77(5)
0.84(5)
0.87(6)
0.92(5)
1.90(6)
2.04(5)
2.10(4)
2.29(6)
2.20(5)
2.45(5)
2.11(5)
2.88(5)
178(6)
150(5)
150 (4)
148(5)
142(5)
133(4)
172(5)
163(4)
–x, –y + 3, –z + 1
O(3)–H(2)···O(1)
x
x
,
y
y
,
,
z
z
N(1)–H(1N1)···O(4)
N(1)–H(2N1)···O(5)
N(2)–H(1N2)···O(5)
N(3)–H(1N3)···O(6)
N(3)–H(2N3)···O(6)
C(6)–H(6)···S(1)
,
x – 1,
x – 1,
y
y
,
,
z
z
x – 1, y – 1,
z
–x
, 1 –
y,
–z
x
,
y
– 1,
z
tions between the supermolecules create supramolecꢀ tate coordination of thiosemicarbazide through the
ular crystal architecture.
sulfur and nitrogen atoms.
Analysis of IR spectroscopy data (Table 5) shows
The absorption bands related to vibrations of the
that, in the IR spectrum of complex
band frequency increases with some decrease in intenꢀ 12–14]. As compared with the IR spectrum of free
sity as compared with the spectrum of free thiosemiꢀ H3SSal, the (C=O) band remains almost unaltered.
I, the thioamide I 5ꢀsulfosalicylate anion were assigned using data in [3,
ν
carbazide. The thioamide II band is also shifted It is worth noting that elimination of the proton from
toward higher frequencies. The intensity of the thioaꢀ the carboxyl group should result in the equivalence of
mide III band considerably decreases. The thioamide IV the carboxyl oxygen atoms and the appearance of two
band frequency decreases. According to [11], such new bands corresponding to the antisymmetric and
changes of thioamide bands correspond to the bidenꢀ symmetric СОО– vibrations at lower frequencies [15].
O(6A)
HB(5')
BC(7')
N(3A)
HB(6')
HB(4')
C(6A)
S(1)
HB(8')
HB(2')
O(4A)
HB(3)
N(1)
HB(1')
Cu(1)
S(1A)
C(1)
N(2)
HB(3')
O(4)
HB(1)
O(2)
O(1)
C(2)
HB(4)
HB(2)
O(3)
N(3)
HB(8)
C(6)
C(8)
HB(6)
HB(5)
S(2)
C(7)
C(4)
HB(7)
C(5)
C(3)
O(5)
O(6)
Fig. 1. Structure of a supermolecule in
shown by dashed lines.
I. In Figs. 1–3, hydrogen bonds are designated as HB with numerals as in Table 4 and are
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 57 No. 4 2012

SYNTHESIS AND CRYSTAL STRUCTURE
513
a
O(6A)
O(5A)
HB(5')
HB(6')
HB(4')
HB(7')
N(3A)
HB(8')
C(6A)
O(4A)
S(1)
O(3A)
HB(2')
O(1A)
N(1A)
HB(3')
O(4)
HB(1')
HB(3)
Cu(1)
HB(1)
O(1)
C(2)
c
0 C(1)
N(1)
HB(4)
HB(2)
O(3)
O(2)
HB(8)
bN(2)
C(8)
S(1A)
N(3)
S(2)
HB(7)
C(7)
C(6)
C(4)
HB(6)
HB(5)
C(5)
O(5)
C(3)
O(6)
Fig. 2. Packing of supermolecules in the (010) plane.
O(6)
O(5)
S(2)
HB(7)
N(2)
N(3)
O(4)
S(1A)
C(1A)
O(3)
O(1)
N(1)
C(1)
0
c
O(2)
HB(6')
HB(3'')
b
Cu(1)
N(1A)
S(1)
O(1A)
O(2A)
O(4A)
N(3A)
O(3A)
HB(4)
N(2A)
HB(6)
HB(7')
S(2A)
O(5A)
O(6A)
HB(7'')
a
Fig. 3. Structure of the cationic layer.
It is evident that the behavior of the carbonyl absorpꢀ cylic acid to complex
I. For νs(SO2), two bands are
tion band in our case is consistent with the lack of observed in the spectrum of complex
I (against three
deprotonation of the COOH group. The (C=C) bands for free 5ꢀsulfosalicylic acid). The decrease in
ν
bands of the aromatic ring also change only slightly. the number of absorption bands arising from symmetꢀ
Noticeable changes are observed for the absorption ric vibrations of the sulfo group is most likely due to
bands of the SO3H band. The νas(SO2) frequencies the fact that it becomes more symmetric, which is
decrease by 8–19 cm–1 in going from free 5ꢀsulfosaliꢀ caused by deprotonation of the SO3H group. Thus, the
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 57 No. 4 2012

514
ANTSYSHKINA et al.
Table 5. Wave numbers (frequencies, cm–1) of absorption bands in the IR spectra of thiosemicarbazide, 5ꢀsulfosalicylic
acid, and the copper(II) 5ꢀsulfosalicylate complex with thiosemicarbazide
Assignment
(NH)
(C=O)
Thioamide I
(C=C) (aromatic ring)
Thioamide II
as(SO )
TSC
H SSal
[Cu(TSC) ](H SSal)
2 2 2
3
ν
3370, 3260, 3170
3371, 3306, 3248, 3178
ν
1678
1670
1530
1315
1562
ν
1477, 1439
1477, 1435
1393, 1369
1215, 1184, 1155, 1126
1084, 1030
975 w.
ν
1234, 1203, 1165, 1134 sh.
1084, 1065, 1026
2
ν
s(SO )
2
Thioamide III
Thioamide IV
1000
800
706
ν(S–O)
663
667
7. P. Starynowicz, J. Alloys Compd. 305, 117 (2000).
IR spectrum of
I
is consistent with the form in which
the 5ꢀsulfosalicylate anion exists in complex
as the singly charged anion deportonated at the sulfo
group.
I
, namely,
8. J.ꢀF. Song, Y. Chen, Z.ꢀG. Li, et al., Polyhedron 26,
4397 (2007).
9. W.ꢀG. Wang, J. Zhang, L.ꢀJ. Song, and Z.ꢀF. Ju, Inorg.
Chem. Comm. , 858 (2004).
7
10. G. M. Sheldrick, SHELXLꢀ93, Program for the
Refinement of Crystal Structures, Univ. of Göttingen,
Germany, 1993.
11. B. Singh, R. Singh, R. V. Chaudhary, and K. P. Thakur,
Ind. J. Chem. 11, 174 (1973).
12. M. S. Nothenberg, A. R. de Souza, and J. R. Matos,
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RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 57 No. 4 2012