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Acta Crystallographica Section EStructure Reports
OnlineISSN 1600-5368

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Tetrakis[pyridine-2(1H)-thione- S]platinum(II) dichloride
Mina Mizota, Yoshimi Yokoyama and Ken Sakai

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Acta Cryst. (2005). E61, m1433–m1435

Mizota et al. ¯ [Pt(C5 H5 NS)4 ]Cl2

metal-organic papers
Acta Crystallographica Section E

Structure Reports
OnlineTetrakis[pyridine-2(1H)-thione-jS]platinum(II)dichloride

ISSN 1600-5368

Mina Mizota,a Yoshimi
Yokoyamab and Ken Sakaib*aDepartment of Applied Chemistry, Faculty ofScience, Tokyo University of Science,
Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601,
Japan, and bDepartment of Chemistry, Faculty ofScience, Kyushu University, Hakozaki 6-10-1,Higashi-ku, Fukuoka 812-8581, Japan
Correspondence e-mail:ksakaiscc@mbox.nc.kyushu-u.ac.jp

Key indicators
Single-crystal X-ray study
T = 296 K
Mean (C–C) = 0.006 Å
R factor = 0.019
wR factor = 0.041
Data-to-parameter ratio = 18.5
For details of how these key indicators wereautomatically derived from the article, see
http://journals.iucr.org/e.

# 2005 International Union of Crystallography
Printed in Great Britain – all rights reserved

Acta Cryst. (2005). E61, m1433–m1435

In the title compound, [Pt(C5H5NS)4]Cl2, the PtII ion is
located at a crystallographic inversion centre, with each Sdonor ligand in its thione tautomeric form [Pt—S = 2.3439 (7)and 2.3444 (7) Å]. The Cl ion positioned at each axial site ofthe PtII ion [Pt  Cl = 3.5171 (8) Å] is hydrogen-bonded to theN—H units of the ligands [Cl  N = 3.103 (3) and 3.125 (3) Å].

Received 17 June 2005
Accepted 27 June 2005
Online 6 July 2005

CommentMetal–metal interactions often give rise to exceptionallyreactive metal centres, leading to the activation of smallmolecules. In this context, we have long been interested in theevolution of H2 from H2O catalyzed by amidate-bridged cisdiammineplatinum(II) dimers, [PtII2(NH3)4(-amidato)2]2+(amidate = acetamidate, 2-fluoroacetamidate, -pyridonate,-pyrrolidinonate, etc.) (Sakai et al., 1993). As extended
studies on the catalysis of such dinuclear systems, efforts havealso been made to develop new electronic systems having
unusual reactivity. Here, we report the synthesis and crystal
structure of the title complex, [Pt(pyridine-2-thione)4]Cl2, (I).

Complex (I) was prepared as a precursor for one of ourtarget molecules, viz. a trinuclear platinum(II) chain complex,[LPt(-B)2Pt(-B)2PtL]2+ [L = 2,20 -bipyridine, (NH3)2, etc.;
B = pyridine-2-thionate], even though the preparation of sucha trimer has been unsuccessful to date. Although an almost
analogous complex involving 4-methylpyridine-2-thione,[Pt(4-methylpyridine-2-thione)4]Cl2MeOH [hereinafter (II)],
was previously prepared from the reaction of K2PtCl4 and4-methylpyridine-2-thione in toluene (Nishioka et al., 1992),
the preparation of (I) according to that method has been
unsuccessful to date, presumably due to the difference in thesolubilities of the two analogous systems. In the present study,compound (I) was found to be produced in good yield basedon our synthetic strategy (see Experimental).
doi:10.1107/S1600536805020209

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Mizota et al.  [Pt(C5H5NS)4]Cl2

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metal-organic papers

Figure 1
The structure of (I), showing the atom-labelling scheme. Displacement
ellipsoids are drawn at the 50% probability level. Unlabelled atoms arerelated to labelled atoms by the symmetry operator (x, y, z). Brokenlines indicate hydrogen bonds.

[Pt  Cl = 3.612 (6) Å]. The ligand is found to serve as amonodentate S-donor ligand in its thione tautomeric form, asillustrated in the scheme. This is a general trend which has
been observed thus far for this series of complexes, e.g. [Pt(4methylpyridine-2-thione)4]Cl2MeOH (Nishioka et al., 1992),[Pd(pyridine-2-thione)4]Cl2 (Umakoshi et al., 1990) and [Pt(1methyl-4-imidazoline-2-thione)4]Cl22H2O (Birker et al.,1982).
The C S bond distances in (I) [1.729 (3) and 1.731 (3) Å]
are slightly longer than those reported for the free or uncoordinated thione molecule [1.692 (2)–1.698 (2) Å; Ohms et al.,1982], which must be caused by a slight decrease in its bondorder due to the formation of  back-donation from d(Pt) tothe *(C S) orbital. As described in an earlier structurereport on 2-thiopyridone, the extent of double-bond characterfor the C—S bond may be estimated using the linear relationship between the order and length of C—S (Penfold,1953). If we adopt the reported correlation (Penfold, 1953),
the double-bond character of the C—S groups in (I) can be
estimated to be ca 40 (5)%. In each pyridine ring, the C—C
unit directly attached to the S atom clearly has a longer
distance than the rest of the C—C units (Table 1), indicatingthat it has a higher single-bond character in comparison withthe remaining bonds. The thione tautomerism is also obvious
from the N—H  Cl hydrogen-bonding geometries summarized in Table 2 (see also Fig. 1).
The two 2-thiopyridone planes, defined by S1/N1/C1–C5
and S2/N2/C6–C10, are tilted with respect to the Pt coordination plane by 65.47 (7) and 64.71 (14) , respectively. Only
one of the two pyridine-2-thione ligands forms a -stack to aneighbouring molecule through an inversion centre, leading to
the establishment of one-dimensional chains propagating
along the [110] direction (Fig. 2). The plane-to-plane separation between the stacked pyridyl planes is estimated at3.527 (2) Å.

Experimental
A solution of cis-PtCl2(DMSO)2 (0.10 mmol, 0.042 g; Price et al.,
1972; DMSO is dimethyl sulfoxide) and pyridine-2(1H)-thione(1.0 mmol, 0.111 g) in methanol (20 ml) was refluxed for 12 h. Aftercooling the solution to room temperature, it was evaporated to a total
volume of ca 7 ml until a small amount of yellow precipitate started todeposit. Leaving the solution to stand in air at room temperature
overnight afforded (I) as yellow plates (yield 70%). Analysis calculated for PtS4Cl2N4C20H20: C 33.80, H 2.84, N 7.88%; found: C 33.82,H 2.82, N 7.88%. IR (KBr, cm1): 2863 (br), 1608 (m), 1570 (s), 1560(m), 1492 (m), 1436 (m), 1139 (s), 1132 (s), 1082 (w), 748 (s), 727 (m).
Figure 2
A view showing the manner in which the molecules of (I) stack along the[110] direction.

As shown in Fig. 1, atom Pt1 of (I) is located at an inversion
centre. Therefore, the PtII ion possesses a crystallographicallyimposed planar geometry. The shortest Pt  Cl distance[3.5171 (8) Å] corresponds to the sum of the van der Waals
radii of Pt and Cl (1.72–1.75 Å for Pt and ca 1.75 Å for Cl;Bondi, 1964), and is slightly shorter than that reported for (II)m1434

Mizota et al.  [Pt(C5H5NS)4]Cl2

Crystal data
[Pt(C5H5NS)4]Cl2
Mr = 710.63
Triclinic, P1
a = 8.3372 (8) Å
b = 9.0754 (8) Å
c = 10.1261 (9) Å = 99.709 (1)
 = 114.142 (1)
 = 104.871 (1)V = 642.4 (1) Å3electronic reprint

Z=1
Dx = 1.837 Mg m3Mo K radiation
Cell parameters from 5806
reflections
 = 2.4–28.2
 = 6.01 mm1
T = 296 (2) KPlate, yellow
0.44  0.23  0.11 mm
Acta Cryst. (2005). E61, m1433–m1435

metal-organic papers
Data collection
2632 independent reflections
2629 reflections with I > 2(I)Rint = 0.058
max = 26.4
h = 10 ! 10
k = 11 ! 11l = 12 ! 12

Bruker SMART APEX CCD areadetector diffractometer! scans
Absorption correction: Gaussian(XPREP in SAINT; Bruker,2001)
Tmin = 0.162, Tmax = 0.535
7352 measured reflections

Refinement
Refinement on F 2
R[F 2 > 2(F 2)] = 0.019
wR(F 2) = 0.041
S = 1.022632 reflections
142 parameters

H-atom parameters constrainedw = 1/[ 2(Fo2) + (0.0093P)2]
where P = (Fo2 + 2Fc2)/3(/)max = 0.001
max = 0.98 e Å3
min = 0.70 e Å3

Table 1

Selected geometric parameters (Å,  ).
Pt1—S2
Pt1—S1
S1—C1
S2—C6
N1—C5
N1—C1
N2—C10C1—C2

2.3439 (7)2.3444 (7)1.731 (3)1.729 (3)1.364 (4)1.367 (4)1.365 (4)1.417 (4)C2  C4i

3.534 (4)S2—Pt1—S1
S2—Pt1—S1ii

88.47 (3)91.53 (3)Pt1—S1—C1—N1

3.6 (2)

C2—C3
C3—C4
C4—C5
C6—C7
C7—C8
C8—C9
C9—C101.379 (5)1.404 (5)1.367 (5)1.414 (4)1.381 (5)1.384 (6)1.356 (6)C1—S1—Pt1
C6—S2—Pt1

109.05 (9)109.67 (10)Pt1—S2—C6—N2

5.8 (3)Symmetry codes: (i) x þ 1; y þ 1; z; (ii) x; y; z.

Table 2

Hydrogen-bond geometry (Å,  ).
D—H  A

D—HH  AD  A

D—H  A

N1—H1A  Cl1
N2—H2A  Cl1

0.86
0.86

2.35
2.32

3.125 (3)3.103 (3)150
152

Acta Cryst. (2005). E61, m1433–m1435

All H atoms were placed at their idealized positions as riding
atoms, with (C—H = 0.93 Å for aromatic rings and N—H = 0.86 Å forthioamide groups, and included in the refinement in a riding-model
approximation, with Uiso(H) = 1.2Ueq(carrier atom).
Data collection: SMART (Bruker, 2001); cell refinement: SAINT(Bruker, 2001); data reduction: SAINT; program(s) used to solve
structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine
structure: SHELXL97 (Sheldrick, 1997); molecular graphics: KENX(Sakai, 2004); software used to prepare material for publication:
SHELXL97, TEXSAN (Molecular Structure Corporation, 2001),
KENX and ORTEP (Johnson, 1976).

This work was partly supported by Grants-in-Aid for
Scientific Research (B) (No. 14340223) and (A) (No.
17205008), and a Grant-in-Aid for Scientific Research on
Priority Area (No. 16074216 of 434: ‘Chemistry of Coordination Space’) from the Ministry of Education, Science, Sports
and Culture of Japan.

References
Birker, P. J. M. W. L., Reedijk, J. & Verschoor, G. C. (1982). Acta Cryst. B38,
2245–2247.
Bondi, A. (1964). J. Phys. Chem. 68, 441–451.
Bruker (2001). SAINT (Version 6.22) and SMART (Version 5.625). Bruker
AXS Inc., Madison, Wisconsin, USA.
Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National
Laboratory, Tennessee, USA.
Molecular Structure Corporation (2001). TEXSAN. Version 1.11r1. MSC,9009 New Trails Drive, The Woodlands, TX 77381-5209, USA.
Nishioka, T., Kinoshita, I., Kitano, K. & Ooi, S. (1992). Chem. Lett. pp. 883–886.
Ohms, U., Guth, H., Kutoglu, A. & Scheringer, C. (1982). Acta Cryst. B38, 831–834.
Penfold, B. R. (1953). Acta Cryst. 6, 707–713.
Price, J. H., Williamson, A. N., Schramm, R. F. & Wayland, B. B. (1972). Inorg.
Chem. 11, 1280–1284.
Sakai, K. (2004). KENX. Kyushu University, Japan.
Sakai, K., Kizaki, Y., Tsubomura, T. & Matsumoto, K. (1993). J. Mol. Catal. 79,142–152.
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University ofGöttingen, Germany.
Umakoshi, K., Ichimura, A., Kinoshita, I. & Ooi, S. (1990). Inorg. Chem. 29,
4005–4010.

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