Ruthenium(II) complexes containing N(4)-tolyl-2-acetylpyridine thiosemicarbazones and phosphine ligands: NMR and electrochemical studies of cis-trans isomerization

Article abstract of DOI:10.1016/j.molstruc.2007.04.032

[Ru(HL)(PPh₃)₂Cl]Cl complexes have been obtained in which HL = N(4)-ortho (complex 1), N(4)-meta (complex 2) and N(4)-para-tolyl 2-acetylpyridine thiosemicarbazone (complex 3). NMR and electrochemical studies indicate that both cis a

Full text of DOI:10.1016/j.molstruc.2007.04.032

Available online at www.sciencedirect.com
Journal of Molecular Structure 875 (2008) 219–225
www.elsevier.com/locate/molstruc
Ruthenium(II) complexes containing N(4)-tolyl-2-acetylpyridine
thiosemicarbazones and phosphine ligands: NMR and
electrochemical studies of cis–trans isomerization
a
a
b
b
Angelica E. Graminha , Alzir A. Batista , Javier Ellena , Eduardo E. Castellano ,
c,
d
d
Letıcia R. Teixeira *, Isolda C. Mendes , Heloisa Beraldo
´
a
Departamento de Quı´mica, Universidade Federal de Sa˜o Carlos, 1365-905 Sa˜o Carlos, Brazil
Instituto de Fı´sica de Sa˜o Carlos, Universidade de Sa˜o Paulo, 13560-970 Sa˜o Carlos, Brazil
b
c
Departamento de Quı´mica, Pontifı´cia Universidade Cato´lica do Rio de Janeiro, 22653-900 Rio de Janeiro, Brazil
d
Departamento de Quı´mica, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, Brazil
Received 22 January 2007; received in revised form 11 April 2007; accepted 20 April 2007
Available online 27 April 2007
Abstract
[Ru(HL)(PPh3)2Cl]Cl complexes have been obtained in which HL = N(4)-ortho (complex 1), N(4)-meta (complex 2) and N(4)-para-
tolyl 2-acetylpyridine thiosemicarbazone (complex 3). NMR and electrochemical studies indicate that both cis and trans isomers exist in
solution, and that the cis isomers are converted into the trans isomers with time. Crystal structure determination of (1) reveals that the
trans isomer is formed in the solid state.
ꢀ 2007 Elsevier B.V. All rights reserved.
Keywords: N(4)-Tolyl thiosemicarbazones; Ruthenium; Phosphines; Cis–trans isomerization
1. Introduction
presently under investigation by many groups [5–8]. There-
fore the preparation of ruthenium complexes with thiose-
micarbazones could be an interesting strategy of
combining the pharmacological properties of the ligand
with that of the metal in one same compound.
Thiosemicarbazones and their metal complexes are
known for their wide pharmacological versatility [1]. The
antitumoral activity of a(N)-heterocyclic thiosemicarbaz-
ones derived from 2-formyl and 2-acetylpyridine has been
extensively investigated as well as the role of coordination
on their mechanisms of action [2,3]. Structure–activity rela-
tionship studies revealed that the presence of a bulky group
attached to the terminal nitrogen of the thiosemicarbazone
chain strongly enhances the pharmacological activity of
these compounds [4].
The discovery that the anti-arthritic drug triethylphos-
phine(2,3,4,6-tetra-O-acetyl-b-1-D-thiopyranosato-S)gold(I)
(auranofin) had antitumoral activity led to the study of
other metal complexes containing phosphine ligands. A
variety of triphenylphosphine complexes have shown to
exhibit significant pharmacological activity [9,10].
In the present work, ruthenium(II) complexes containing
N(4)-ortho-, N(4)-meta and N(4)-para-tolyl 2-acetylpyridin-
ethiosemicarbazone (Fig. 1) and triphenylphosphine as
ligands have been obtained. NMR and electrochemical stud-
ies of cis–trans isomerization were carried out. The pharma-
cological profile of these complexes is presently under
investigation.
Ruthenium complexes are also known for their antitu-
moral properties and the possibility of producing ruthe-
nium-based compounds for the treatment of cancer is
*
Corresponding author. Tel.: +55 21 3527 1813; fax: +55 21 3527 1637.
E-mail address: lregina@qui.puc-rio.br (L.R. Teixeira).
0022-2860/$ - see front matter ꢀ 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.molstruc.2007.04.032

220
A.E. Graminha et al. / Journal of Molecular Structure 875 (2008) 219–225
3H, C(7)H3); 2.22, 2.06 (s, 3H, C(15)H3). 31P{1H} NMR
2
(CH2Cl2 d/ppm): 23.3 (s); 40.8 (d, JP–P/Hz 28.7); 38.6 (d,
2JP–P/Hz 29.0).
2.2. Physical measurements
Elemental analyses were performed on a Fison equip-
ment, model EA 1108. A Radiometer Copenhagem Meter
Lab., model CDM 230 was employed for molar conductiv-
ity measurements. Infrared spectra (KBr pellets) were
obtained using a BOMEM MICHELSON instrument,
model 102. NMR spectra were obtained at room tempera-
ture with a Brucker DRX-400 Avance (400 MHz) spec-
trometer. For 1H measurements CDCl3 was used as
solvent and tetramethylsilane (TMS) as internal reference
and for 31P{1H} (161 MHz) CH2Cl2 was used as solvent
and H3PO4 85% as external reference.
The electrochemical experiments were carried out at
room temperature in dichloromethane containing
0.1 mol LÀ1 tetrabutylammoniumperchlorate (TBAP,
Fluka Purum) using an electrochemical analyzer from Bio-
analytical Systems Inc. (BAS), model 100BW. The working
and auxiliary electrodes were stationary Pt foils, and the
reference electrode was Ag/AgCl, a medium in which ferro-
cene is oxidized at 0.48 V (Fc+/Fc).
Fig. 1. General structure of N(4)-ortho (H2Ac4oT), N(4)-meta
(H2Ac4mT) and N(4)-para-tolyl-2-acetylpyridine thiosemicarbazone
(H2Ac4pT).
2. Experimental
2.1. Synthesis
The thiosemicarbazones were prepared as described in the
literature [11]. Briefly, 2-acetylpyridine (6 mmol) was added
to a slight excess of hydrazine hydrate in ethanol under
reflux. The resulting hydrazone (5 mmol) was added to
ortho-meta- or para-tolyl isothiocianate (5 mmol) in ethanol
under reflux. The solids which precipitated were filtered and
washed with isopropanol then diethylether and dried.
The complexes were obtained by dissolving the desired
thiosemicarbazone (0.20 mmol) in CH2Cl2(20 mL) with gen-
tle heating under argon atmosphere. After cooling the solu-
tion to room temperature [RuCl2(PPh3)3] (0.20 mmol) was
added. The complexes which form immediately precipitate
by addition of diethyl ether. The solids were filtered and
washed with methanol and diethyl ether and dried in vacuo.
[Ru(H2Ac4oT)(PPh3)2Cl]Cl (1): Yield: 0.140 g (71.4%).
Anal. Calc: C, 62.45; H, 4.73; N, 5.71%. Found: C,
62.22; H, 4.69; N, 5.68 %. Molar conductivity (lS cmÀ1):
33.85 (CH2Cl2). IR (KBr m/cmÀ1): 1556 (C@N); 746
(C@S); 620 (qpy); 531, 521 (Ru–P); 498 (Ru–N); 417
(Ru–S); 284 (Ru–NPY); 332 (Ru–Cl). 1H NMR (CDCl3
d/ppm): 13.25, 12.70 (s, 1H, N(2)–H); 10.94, 10.62 (s, 1H,
N(4)–H); 2.57, 2.31 (s, 3H, C(7)H3); 2.07, 2.05 (s, 3H,
C(15)H3). 31P{1H} NMR (CH2Cl2 d/ppm): 24.4 (s); 41.2
2.3. X-ray crystallography
Room temperature X-ray diffraction data collection
(/ scans and x scans with j offsets) of trans[Ru(H2A-
c4oT)(PPh3)2Cl]Cl was performed on an Enraf-Nonius
Kappa-CCD diffractometer (95 mm CCD camera on
j-goniostat) using graphite-monochromated MoKa radia-
˚
tion (0.71073 A). Data were collected up to 50ꢁ in 2h, with
a redundancy of 4. The final unit cell parameters were
based on all reflections. Data collections were carried out
using the COLLECT program [12]; integration and scaling
of the reflections were performed with the HKL Denzo-
Scalepack system of programs [13]. Analytical absorption
correction was applied [14].
2
2
(d, JP–P/Hz 28.9); 38.5 (d, JP–P/Hz 28.8).
[Ru(H2Ac4mT)(PPh3)2Cl]Cl (2): Yield: 0.148 g (75.5%).
Anal. Calc: C, 62.45; H, 4.73; N, 5.71%. Found: C, 61.96;
H, 4.71; N, 5.67 %. Molar conductivity (lS cmÀ1): 34.15
(CH2Cl2). IR (KBr m/cmÀ1): 1556 (C@N); 744 (C@S);
618 (qpy); 525, 520 (Ru–P); 499 (Ru–N); 418 (Ru–S); 305
(Ru–NPY); 329 (Ru–Cl).1H NMR (CDCl3 d/ppm):
12.88, 12.11 (s, N(2)–H); 11.45, 11.09 (s, N(4)–H); 2.51,
The structure was solved by direct methods with SHEL-
XS-97 [15a]. The model was refined by full-matrix least
squares on F2 with SHELXL-97 [15b]. All hydrogen atoms
were stereochemically positioned and refined with the rid-
ing model [15b]. Hydrogen atoms of the CH groups were
set isotropic with a thermal parameter 20% greater than
the equivalent isotropic displacement parameter of the
atom to which each one was bonded. This percentage
was set to 50% for the hydrogen atoms of the CH3 group.
The programs SHELXL-97 [15b], and ORTEP-3 [16] were
used within WinGX [17] to prepare materials for
publication.
2.28 (s, 3 H, C(7)H3); 2.19, 2.03 (s, 3H, C(15)H3).
2
31P{1H} NMR (CH2Cl2 d/ppm): 23.8 (s); 41.2 (d, JP–P
Hz 28.3); 39.0 (d, JP–P/Hz 28.6).
/
2
[Ru(H2Ac4pT)(PPh3)2Cl]Cl (3): Yield: 0.136 g (69.4%).
Anal. Calc: C, 62.45; H, 4.73; N, 5.71%. Found: C,
62.01; H, 4.70; N, 5.67 %. Molar conductivity (lS cmÀ1):
33.65. IR (KBr m/cmÀ1): 1553 (C@N); 745 (C@S); 619
(qpy); 533, 520 (Ru–P); 498 (Ru–N); 418 (Ru–S); 288
3. Results and discussion
1
(Ru–NPY); 324 (Ru–Cl). H NMR (CDCl3 d/ppm): 12.89,
Microanalyses and molar conductivity data suggest
12.09 (s, N(2)–H); 11.42, 11.04 (s, N(4)–H); 2.51, 2.27 (s,
the formation of [Ru(H2Ac4oT)(PPh3)2Cl]Cl (1),

A.E. Graminha et al. / Journal of Molecular Structure 875 (2008) 219–225
221
Fig. 2. 31P{1H} NMR spectra of (a) cis/trans[RuCl(H2Ac4mT)(PPh3)2]Cl and (b) cis/trans[RuCl(H2Ac4oT)(PPh3)2]Cl recorded immediately after
dissolution and after 24 h.

222
A.E. Graminha et al. / Journal of Molecular Structure 875 (2008) 219–225
Table 1
Cyclic voltammetry data for complexes (1)–(3) (0.100 V sÀ1, CH2Cl2, 0.1 mol LÀ1 TBAP)
Process 1 (cis isomer)
Process 2 (trans isomer)
RuII/RuIII (V)
RuIII/RuII (V)
RuII/RuIII (V)
RuIII/RuII (V)
cis/trans[Ru(H2Ac4oT)(PPh3)2Cl]Cl (1)
cis/trans[Ru(H2Ac4mT)(PPh3)2Cl]Cl (2)
cis/trans[Ru(H2Ac4pT)(PPh3)2Cl]Cl (3)
0.47
0.47
0.48
0.37
0.31
0.29
0.78
0.75
0.75
0.60
0.57
0.58
[Ru(H2Ac4mT)(PPh3)2Cl]Cl (2) and [Ru(H2Ac4pT)(PPh3)2-
Cl]Cl (3). The molar conductivity data indicate that all com-
plexes are 1:1 electrolytes, in accordance with the proposed
formulations.
to 1553–1556 cmÀ1 in the complexes, indicating coordina-
tion of the imine nitrogen [18,19]. The absorption at 782–
796 cmÀ1 in the spectra of the free ligands, attributed to
the m(C@S) vibration, shifts to 744–746 cmÀ1(37–50 cmÀ1
)
in the spectra of the complexes, indicating complexation
through a thione sulfur [20]. The in-plane deformation mode
of the pyridine ring observed in the 590–608 cmÀ1region in
the spectra of the uncomplexed thiosemicarbazones shifts
to 618–620 cmÀ1 in the spectra of the complexes, in accor-
dance with coordination through the heteroaromatic nitro-
gen [18–20]. Two absorptions at 520–533 cmÀ1were
attributed to the m(Ru–P) mode which is split, indicating
the presence of two phosphorus atoms in cis position to each
other. However, since a trans isomer would present a single
absorption attributed to m(Ru–P) in the same region, the
presence of both cis and trans isomers in the powder cannot
be discarded. Absorptions at 498–499 cmÀ1, 417–418 cmÀ1
and 284–305 cmÀ1 in the spectra of the complexes were
attributed to the m(Ru–N), m(Ru–S) and m(Ru–Npy), vibra-
tions [21], indicating coordination of the thiosemicarbazones
through the Npy–N–S chelating system. Absorptions at 324–
332 cmÀ1 in the spectra of the complexes were attributed to
the m(Ru–Cl) vibration [21].
3.1. IR spectral studies
In the infrared spectra, the m(C@N) stretching vibra-
tion of the thiosemicarbazones at 1580–1582 cmÀ1 shifts
3.2. NMR spectral studies
31P{1H} NMR spectra of complexes (1)–(3) (using
CH2Cl2 as solvent) have been recorded immediately
after dissolution and after 24 h. In the 31P{1H} NMR
spectra of (1)–(3) the singlet at d23.3–d24.4 was attrib-
uted to trans[Ru(HL)(PPh3)2Cl]Cl (HL = N(4)-o-, N(4)-
m or N(4)-p-tolyl 2-acetylpyridine thiosemicarbazone)
and the two doublets at d38.5–41.2 (2JP–P = 29 Hz) were
assigned to the corresponding cis complexes, in which
one phosphorus atom is trans to the chloride ligand
and the second is trans to the imine nitrogen of the thi-
osemicarbazone chain. In all cases the intensities of the
two doublets decrease with time, suggesting conversion
of the cis to the trans isomer, probably due to sterical
effects that favor the formation of the trans isomeric
form. For complexes (2) and (3) the 31P{1H} NMR
spectra immediately after dissolution indicated predomi-
nance of the trans isomer (67%). After 24 h 75% of the
trans isomer exist in solution (see Fig. 2a). Similarly, in
the case of complex (1) the trans isomer predominates
(61%) immediately after dissolution. After 24 h only
the trans isomer is present, suggesting that in this case
cis–trans conversion is faster (see Fig. 2b).
Fig. 3. (a) Cyclic voltammogramm and (b) Differential pulse voltammo-
gram of cis/trans[RuCl(H2Ac4oT)(PPh3)2]Cl (wave 1 corresponds to the
cis isomer and wave 2 to the trans isomer, CH2Cl2, 0.1 mol LÀ1 TBAP);
(—) immediately after dissolution and (- -) 10 min after dissolution.

A.E. Graminha et al. / Journal of Molecular Structure 875 (2008) 219–225
223
The 1H NMR spectra of the thiosemicarbazones in
CDCl3 show a singlet at d9.30 which is attributed to
N(2)–H. This signal appears duplicated at d12.09–13.25
range in the spectra of (1)–(3) in accordance with the
presence of the cis and trans isomers in solution. The
signal at d8.80 in the spectra of the thiosemicarbazones
was attributed to N(4)–H. Similarly two signals of
N(4)–H at d10.62–11.45 were observed in the spectra
of (1)–(3), which have been assigned to the cis and trans
isomers. In addition, four signals were present in the
spectra of the complexes, attributed to the methyl
hydrogens of the acetyl and tolyl groups of the cis
and trans isomers. In the spectrum of (1) the signals
at d2.29 and 2.05 were assigned to the acetyl and tolyl
hydrogens of the trans isomer and those at d 2.57 and
2.07 to these hydrogens of the cis isomer. In the spec-
trum of (2) the acetyl and tolyl hydrogens were found
at d2.28 and d2.19, respectively (trans isomer), and at
d2.51 and d2.03 (cis isomer) and in the spectrum of
(3) the acetyl and tolyl hydrogens were found at d2.27
and d2.22, respectively (trans isomer), and at d2.51
and d2.06, respectively (cis isomer).
Crystal structure determination of (1) (see below) reveals
that the trans isomer is obtained, confirming that the trans
species is indeed the thermodynamically most stable. As
mentioned before, infrared data have indicated that either
the cis isomer or both cis and trans isomers were present
in the powder. Since the 31P{1H} NMR spectra immedi-
ately after dissolution already showed the presence of both
isomers, we may infer that the two compounds were pres-
ent in the powder. Only the trans isomer crystallized from
the filtrate.
Table 2
Crystal data, structure solution methods and refinement results for
trans[Ru(H2Ac4oT)(PPh3)2Cl]Cl (1)
Empirical formula
Formula weight
Temperature
Wavelength
Crystal system
Space group
C51H46N4P2SCl2Ru
980.93
293(2) K
˚
0.71073 A
Monoclinic
P21/n
˚
Unit cell dimensions
a = 9.7090(10) A
˚
b = 40.210(4) A
b = 90.163(7)ꢁ
˚
c = 11.917(2) A
3
˚
Volume
Z
4652.4(10) A
4
Density (calculated)
Absorption coefficient
F(000)
Crystal size
Theta range for data
collection
1.399 Mg/m3
0.605 mmÀ1
2012
0.43 · 0.08 · 0.02 mm3
3.10–25.00ꢁ
Index ranges
À11 6 h 6 11, À11 6 k 6 47,
À14 6/614
Reflections collected
Independent reflections
Completeness to
14196
7340 [R(int) = 0.1553]
89.8%
theta = 25.00ꢁ
Absorption correction1
Gaussian
Max. and min. transmission 0.988 and 0.912
Refinement method Full-matrix least squares
on F2
Data/restraints/parameters 7340/0/552
Goodness-of-fit on F2
1.065
Final R indices [I > 2r(I)] R1 = 0.0965, wR2 = 0.2516
R indices (all data) R1 = 0.1712, wR2 = 0.2833
À3
˚
Largest diff. peak and hole 1.066 and À0.753 e A
aData collection, data processing, structure solution and structure refine-
ment, respectively.
Fig. 4. ORTEP view of trans[Ru(H2Ac4oT)(PPh3)2Cl]Cl, showing the labeling of the non-hydrogen atoms and their displacement ellipsoids at the 50% level.

224
A.E. Graminha et al. / Journal of Molecular Structure 875 (2008) 219–225
Interestingly other authors have reported a study of
ORTEP3 view of the molecule. Table 3 shows selected
bond distances [A] and angles [ꢁ]. The structure was refined
in the monoclinic system, P21/n with four molecules in the
asymmetric unit.
complex (3) [22] but did not report 31P{1H} NMR spec-
tra and did not mention the cis–trans isomerization process
reported by the first time in the present investigation.
˚
The structure of complex (1) reveals that the thiosemi-
carbazone coordinates through the Npy–N(2)–S chelating
system. The remaining coordination positions are occupied
by two triphenylphosphine groups trans to each other and
a chloride which is trans to N(2).
3.3. Electrochemical studies
Table 1 shows the electrochemical data for (1)–(3). The
voltammograms exhibit two quasi-reversible processes
attributed to the RuII/RuIII oxidation (Fig. 3a). The first
process in the 0.29–0.48 V range, which disappears with
time is assigned to the cis isomer. The second, which occurs
in the 0.57–0.78 V range, becomes more intense, as
observed in the differential pulse voltammograms, and
was attributed to the trans isomer (see Fig. 3b). Two con-
secutive reduction waves were observed in the À0.67 to
À0.70 V and in the À1.27 to À1.42 V ranges, which have
been assigned to redox processes of the thiosemicarbazone.
These two reduction signals could be assigned to a two-step
two-electron reduction process involving first the cleavage
of the N–N single bond by reduction with two electrons
and then reduction by two electrons at the imine formed,
as suggested for pyridine-derived thiosemicarbazones and
semicarbazones [23–25].
The previously published study of complex (3) [22]
reported the electrochemical behavior of the complex but
did not mention the presence of cis–trans isomers in solu-
tion, which were clearly evidenced in the present
investigation.
At this point it is worth noticing that while in the
present study the preparations of complexes (1)–(3)
were carried out at room temperature, in the previously
published work the synthesis of complex (3) was carried
out under reflux (4 h). These conditions could have
favored complete conversion of the cis to the trans
isomer.
Distortion from perfect octahedral geometry is caused
˚
by N(1), which is 0.11(1) A apart from the plane formed
by Ru, N2 and Cl1. The angle formed by the line through
P1 and P2 with this plane is 2.2(1)ꢁ and the P1–Ru–P2
bond angle is 176.2(1)ꢁ.
Analyses of the supra-molecular organization shows
an intermolecular interaction between N3–H3. . .Cl2
˚
˚
(N3..Cl2 = 3.056(1) A, H3. . .Cl2 = 2.289(4)A, N3–H3. . ..
Cl2 = 148.6(7)ꢁ) that fixes the position of the chloride
ion.
Other authors determined the crystal structure of trans[-
Ru(H2Ac4pT)(PPh3)2Cl]Cl (complex (3) of the present
paper) [22]. Comparison between the structures of the
two complexes reveals some differences in bond distances
˚
and angles. The C8–S bond distance is 1.726(14) A in (1)
˚
and 1.706(6) A in (3); the C8–N3 bond distance is
˚
˚
1.366(16) A in (1) and 1.359(7) A in (3); the N2–N3 bond
˚
˚
distance is 1.366(13) A in (1) and 1.383(7) A in (3). The
Ru–N(1) bond distance is 2.118(10) A in (1) and
2.085(5) A in (3). In (1) the Ru–P1 distance is 2.410(4) A
and the Ru–P2 distance is 2.381(4) A whereas the two
˚
˚
˚
˚
˚
Ru–P distances are equal (2.399(1) A) in (3).
The N2–Ru–N1 angle is 78.8(4)ꢁ in complex (1) and 77.4
(2)ꢁ in (3); the N1–Ru–S angle is 161.4(3)ꢁ in (1) and
160.8(1)ꢁ in (3) and P2–Ru–P1 is 176.19(13)ꢁ in (1) and
175.2(1)ꢁ in (3).
Acknowledgement
3.4. Crystal structure of trans[Ru(H2Ac4oT)(PPh3)2Cl]Cl
This work was supported by CNPq and FAPESP of
Brazil.
Crystal data and refinement results for trans[Ru(H2A-
c4oT)(PPh3)2Cl]Cl (1) are shown in Table 2. Fig. 4 is the
Appendix A. Supplementary data
Listings of fractional coordinates and equivalent isotro-
pic displacement parameters (Tables 1S), full bond dis-
tances and angles (Tables 2S), atomic anisotropic
displacement parameters (Table 3S), hydrogen atoms posi-
tions (Table 4S) and complete list of torsion angles (Tables
5S). Crystallographic data for complex (1) have been
deposited at Cambridge Crystallographic Data Centre as
supplementary publication number CCDC 632565. Copies
of available material can be obtained on application to
CCDC, 12 Union Road, Cambridge CB2 1Ez, UK (fax:
44 1223 336033 or e-mail: deposit@ccdc.cam.ac.uk).
Supplementary data associated with this article can be
found, in the online version, at doi:10.1016/j.molstruc.
2007.04.032.
Table 3
˚
Selected bond lengths [A] and angles [ꢁ] for trans[Ru(H2Ac4oT)
(PPh3)2Cl]Cl
S–C(8)
1.726(14)
1.346(15)
1.366(13)
1.366(16)
1.330(16)
1.50(2)
1.985(11)
2.118(10)
2.410(4)
2.381(4)
2.386(3)
2.449(3)
N(2)–N(3)–C(8)
N(3)–C(8)–S(1)
N(4)–C(8)–N(3)
N(4)–C(8)–S(1)
C(6)–N(2)–N(3)
C(8)–N(4)–C(9)
N(2)–Ru–N(1)
N(1)–Ru–S
118.3(11)
120.5(10)
113.1(12)
126.4(11)
119.2(10)
120.5(12)
78.8(4)
161.4(3)
176.19(13)
177.0(3)
98.4(3)
N(2)–C(6)
N(2)–N(3)
N(3)–C(8)
N(4)–C(8)
N(4)–C(9)
Ru–N(2)
Ru–N(1)
Ru–P(1)
Ru–P(2)
Ru–S
P(2)–Ru–P(1)
N(2)–Ru–Cl(1)
N(1)–Ru–Cl(1)
Ru–Cl(1)

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225
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