Synthesis and X-ray characterization of two isomeric dichloro bis-{1-(phenylazo)isoquinoline} complexes of ruthenium(II)

Article abstract of DOI:10.1016/S0277-5387(02)01436-5

The azoimine functionalized ligand, 1-(phenylazo)isoquinoline (paiq) was synthesized and reacted with RuCl₃ in dry ethanol under nitrogen atmosphere to produce two isomeric dichloro bis-[1-(phenylazo)isoquinoline] ruthenium(II) complexes. They are green isomer (a) and blue isomer (b). In the X-ray crystal structure determination, the final reliability indices for isomers (a) and (b) are 0.0308 and 0.0448, respectively. Solvents for crystallization are found in both crystal structures. Of the five possible geometrical isomeric configurations of RuL₂Cl₂, L = 1-(phenylazo)isoquinoline, in order of the coordinating pairs: (Cl, Cl); (N,N); (N′,N′) where N represents N(isoquinoline), N′ represents N(azo), the two isomers isolated are trans-cis-cis (tcc, a) and cis-cis-cis (ccc-b). Both the green isomer (a) and the blue isomer (b) have six coordination. The coordination geometry of ruthenium(II) for the former (a) compound is distortedly octahedral with the surrounding four nitrogen atoms equatorial and two chlorine atoms axial. That for the latter isomer (b) is also a distorted octahedron with Cl2, Nl, N3 and N6 atoms basal, and Cl1 and N4 atoms apical. The Ru-Cl distances for the green tcc-isomer (a) are shorter than those for the blue ccc-isomer (b). The Ru-N bond lengths in both isomer split into two categories.

Full text of DOI:10.1016/S0277-5387(02)01436-5

Polyhedron 22 (2003) 535Á541
/
www.elsevier.com/locate/poly
Synthesis and X-ray characterization of two isomeric dichloro
bis-{1-(phenylazo)isoquinoline} complexes of ruthenium(II)
Tian-Huey Lu a,*, Tarun Kumar Misra b, Po-Ching Lin a, Fen-Ling Liao b,
Chung-Sun Chung b
a Department of Physics, National Tsing Hua University, Hsinchu 300, Taiwan, ROC
b Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan, ROC
Received 22 August 2002; accepted 19 November 2002
Abstract
The azoimine functionalized ligand, 1-(phenylazo)isoquinoline (paiq) was synthesized and reacted with RuCl3 in dry ethanol
under nitrogen atmosphere to produce two isomeric dichloro bis-[1-(phenylazo)isoquinoline] ruthenium(II) complexes. They are
green isomer (a) and blue isomer (b). In the X-ray crystal structure determination, the final reliability indices for isomers (a) and (b)
are 0.0308 and 0.0448, respectively. Solvents for crystallization are found in both crystal structures. Of the five possible geometrical
isomeric configurations of RuL2Cl2, Lꢀ
/
1-(phenylazo)isoquinoline, in order of the coordinating pairs: (Cl, Cl); (N,N); (N?,N?)
where N represents N(isoquinoline), N? represents N(azo), the two isomers isolated are trans Á
/
cis Ácis (tcc, a) and cis Ácis Ácis (ccc,
/
/
/
b). Both the green isomer (a) and the blue isomer (b) have six coordination. The coordination geometry of ruthenium(II) for the
former (a) compound is distortedly octahedral with the surrounding four nitrogen atoms equatorial and two chlorine atoms axial.
That for the latter isomer (b) is also a distorted octahedron with Cl2, N1, N3 and N6 atoms basal, and Cl1 and N4 atoms apical. The
Ruꢀ
/
Cl distances for the green tcc-isomer (a) are shorter than those for the blue ccc-isomer (b). The Ruꢀ
/N bond lengths in both
isomer split into two categories.
# 2003 Elsevier Science Ltd. All rights reserved.
Keywords: Phenylazoisoquinolin; Ruthenium(II) complexes; Isomers; X-ray structures
1. Introduction
isoquinoline as an N-heterocycle with a pendant azo
arm.
The chemistry of ruthenium(II) complexes containing
Isoquinoline was contemplated because of its poten-
tial application in medicinal alkaloids. The ring struc-
ture of isoquinoline is of great consequence in medicinal
plant alkaloids and as a result has found application in
chemotherapy [7]. Morphine and codeine are well
azoimine (ꢀ
/
Nꢁ
/
Nꢀ
/
Cꢁ
/
Nꢀ
/
) and diimine (ꢀ
/
Nꢁ
/
Cꢀ
/
Nꢁ
/
Cꢀ
/
)
functional units have been reported elsewhere [1Á
/
6].
These two functions are isoelectronic and p-acidic in
character. The advantage of the azoimine functional
unit is that it has a strong ability to stabilize low valent
metal redox states, such as Ru(II), Os(II), Pd(II), Pt(II),
Ag(I), Cu(I) etc. Thus the chemistry of azoimine
functionalized ligand complexes enamoured us to take
an endeavor to develop a new ligand containing an
azoimine unit. Our ligand skeleton is made up by an
known analgesics, emitine is an antiamoebic*all are
/
regarded as tetrahydroisoquinoline derivatives. Ber-
berin, a protoberberine dihydrodibenzoisoquinolizinium
alkaloid containing the typical tetracyclic ring structure,
has found applications as an antibacterial, antimalarial
and antipyretic compound [8]. A small group of
isoquinoline alkaloids, for example corydaldine, is
known to have medicinal importance [8].
It is presumable that the coordination chemistry plays
an important role in biological molecules such as
hemoglobin [9], chlorophyll [10] and vitamin E [11,12].
The metal usually coordinates with oxygen, nitrogen
* Corresponding author. Tel.: ꢁ
3052.
E-mail
cschung@mx.nthu.edu.tw (C.-S. Chung).
/
886-3-574-2543; fax: ꢁ
/
886-3-572-
addresses:
thlu@phys.nthu.edu.tw
(T.-H. Lu),
0277-5387/03/$ - see front matter # 2003 Elsevier Science Ltd. All rights reserved.
doi:10.1016/S0277-5387(02)01436-5

536
T.-H. Lu et al. / Polyhedron 22 (2003) 535Á541
/
and sulfur atoms in the coordination compound [13].
Several types of ruthenium metal complexes have shown
high in vitro and in vivo antitumor activity and some
compounds are in advanced stages of preclinical studies
characterization of tcc-(dichloro){bis-(1-phenylazoiso-
quinoline)}ruthenium(II) and ccc-(dichloro){bis-(1-phe-
nylazoisoquinoline)}ruthenium(II) complexes. A study
of some coordinated bond lengths of these ligand
complexes with other similar ligand complexes of
ruthenium(II) have been summarized and compared
herein.
[14Á17]. Although the mechanism of action of anti-
/
tumor-active ruthenium compounds is not fully under-
stood yet, it is thought that, similar to the platinum
drugs [18Á21], the chloride complexes can hydrolyze in
/
vivo, allowing the Ru to finally bind to the nucleobases
of the DNA. Very recently the remarkably different
cytotoxicity data in vitro of a series of human tumor cell
lines of the three isomers of dichloro bis-{2-(phenylazo)
pyridine)} ruthenium(II) complexes has been investi-
gated [22]. Crystal structures of these isomers are
reported [22,23].
Our successfully synthesized new ligand (L), 1-phe-
nylazoisoquinoline (Scheme 1), is an unsymmetrical
N,N?-bidentate ligand, lacks a twofold symmetry axis
and on complexation with ruthenium(II), affords
pseudo-octahedral, RuL2Cl2 complexes.
2. Experimental
2.1. Materials
1-Aminoisoquinoline, nitrosobenzene and RuCl3×
/
xH2O were purchased from Aldrich. Ruthenium
trichloride hydrate was treated before use as earlier [1].
All other chemicals and solvents were of reagent grade
and were used without further purification.
2.2. Preparation of the ligand 1-(phenylazo)isoquinoline
(paiq)
Theoretically, the RuL2Cl2, complex formula bestows
five geometrical isomers: trans Á
trans Átrans (ttt); cis Átrans Ácis (ctc); cis Á
(cct); and cis Ácis Ácis (ccc) (Scheme 1). We were able
to isolate only two isomers among the five isomers. In
this paper we wish to describe the synthesis and X-ray
/
cis Á
/
cis (tcc); trans Á
/
/
/
/
/
cis Átrans
/
To a solution of 1-aminoisoquinoline (1.0 g, 6.94
mmol) in dry benzene (25 ml) in the presence of
molecular sodium (0.5 g), nitrosobenzene (0.75 g, 7.0
mmol) was added slowly in small portions for 2 h and
/
/
Scheme 1.

T.-H. Lu et al. / Polyhedron 22 (2003) 535Á
/541
537
refluxed under nitrogen atmosphere. The reaction was
further continued for 3 h and cooled to room tempera-
ture (r.t.). The dark red solution was then filtered and
the filtrate was washed thoroughly with water three to
four times. The solution was concentrated by vacuum
distillation and then subjected to column chromatogra-
Table 1
Summarized crystallographic data for complexes a and b
Crystal parameters
Green tcc isomer (a)
Blue ccc isomer (b)
Formula
M
C
723.43
31H24Cl4N6Ru
C35H23Cl2N6O2Ru
731.56
monoclinic
C2/c
Crystal system
Space group
triclinic
¯
phy (30ꢂ
/
1 cm) on silica gel (60Á120 mesh). The desired
/
P
/1/
compound, a red band, was eluted with benzene and
concentrated by distillation. A gummy mass of the
ligand was obtained by evaporation of the solvent.
The yield was 42%.
˚
a (A)
10.213(2)
11.616(2)
14.297(3)
110.497(3)
105.189(3)
91.952(3)
1518.5(5)
0.71073
1.582
25.040(7)
14.816(4)
19.780(6)
90
˚
b (A)
˚
c (A)
a (8)
b (8)
113.873(5)
90
g (8)
3
V (A )
2.3. Preparation of two complexes of isomeric
˚
6710(3)
0.71073
1.448
˚
Ru(paiq)2Cl2, trans Á
azo)isoquinoline}ruthenium(II) (green isomer, a)
and cis Ácis Ácis-dichlorobis-{1-(phenylazo)-
isoquinoline}ruthenium(II) (blue isomer, b)
/
cis Ácis-dichlorobis-{1-(phenyl-
/
Wavelength (A)
)
rcalc (Mg mꢃ3
Z
Temperature (K)
2
294(2)
8
294(2)
/
/
m (Mo Ka) (mmꢃ1
Refined parameters
)
0.901
385
0.667
384
a
RuCl3×/xH2O (0.2 g, 0.76 mmol) was dissolved in 20
R
wR
0.0308
0.0840
1.095
0.0448
0.1403
0.713
ml of dry ethanol and was refluxed with stirring for 5 h
under nitrogen atmosphere. During this period the color
of the solution changed from brown to green. Then 0.36
g (1.53 mmol) of the ligand, 1-(phenylazo)isoquinoline
(paiq) in 5 ml dry ethanol was added and the mixture
was refluxed for an additional 4 h. The color of the
solution became bluish-green with a dark precipitate.
The solution was cooled to r.t., filtered and washed
thoroughly with water, ethanol and finally with diethy-
lether. The precipitate was then dried in vacuum. The
dried product was dissolved in small volume of CH2Cl2
and then subjected to column chromatography on
b
Goodness-of-fit
a
Rꢀ
/
[a[Foꢃ
/
Fc]/a Fo].
b
GOF is defined as [w(Foꢃ
/Fc)/(noꢃ
/
nc)]1/2 where no and nc denote
the numbers of data and variables, respectively.
direct method. Successively alternative difference Four-
ier synthesis and full-matrix least-squares fit were
applied to solve the two whole structures [25]. Both
structures contain solvent(s) in somewhat disorder,
besides the expected model molecule. From the differ-
ence Fourier map by using the calculated structure
alumina. A green band was eluted by 5:1 benzeneÁ
acetonitrile mixture and a blue band was eluted by 1:1
benzeneÁacetonitrile mixture. Crystals suitable for sin-
/
factor for the model, residues higher than 3 e Aꢃ3 were
˚
found. Judging from the solvents we added to synthesize
the compound and to grow the crystals, the solvent(s) in
the structures were located. They were CH2Cl2 (dichlor-
omethane) for the green tcc isomer, and C6H6 (benzene),
CH3CH2OH (ethanol) and H2O (water molecule) for the
blue ccc isomer. The structures were determined by
using SHELX-97 [26] and their ORTEP were plotted by
NRCVAX [27].
/
gle X-ray diffraction were grown by slow evaporation of
the eluted solution at r.t.
2.4. X-ray crystallography
Crystals suitable for X-ray work were cut into the size
of 0.30ꢂ
/
0.30ꢂ
/
0.20 mm for green isomer (a) and
0.23 mm for blue isomer (b). X-ray
0.30ꢂ0.25ꢂ
/
/
diffraction data were collected on a Siemens SMART
3. Results and discussion
CCD diffractometer with graphite monochromatized
˚
0.71073 A) at 295 K. The crystal
Mo Ka radiation (lꢀ
/
data and the collection parameters are listed in Table 1.
The data were corrected for Lorentz-polarization factors
and absorption effects. An empirical absorption was
applied based on the azimuthal rotation from reflections
[24]. Systematic absences led to the identification of
space groups as shown in Table 1. Of the total measured
14 814 (a) and 19 731 (b) reflections, 6632 and 7488 are
3.1. Synthesis
1-(Phenylazo)isoquinoline (paiq, Scheme 1) was
synthesized by condensing nitrosobenzene with 1-ami-
noisoquinoline in the presence of metallic sodium in dry
benzene under refluxing conditions for 5 h. The ligand
was purified by column chromatography on silica gel.
The ligand is new and acted as an unsymmetrical
bidentate N,N-chelating ligand. The donor centers are
abbreviated as N(isoquinoline), N and N(azo), N? and
the atom numbering is shown in Scheme 1. Ru(II)-
unique, 5911 and 5664 are significant (I ꢀ2s(I)) and
/
used for structure determination, respectively. The
initial phases for both isomers were determined by the
conventional heavy atom method and checked by a

538
T.-H. Lu et al. / Polyhedron 22 (2003) 535Á541
/
complexes, Ru(paiq)2Cl2, were generated when RuCl3×
/
xH2O was refluxed in dry ethanol under N2-atmosphere
followed by the addition of the ligand via spontaneous
reductive chelation. Upon cooling, mainly green isomer
with a small amount of blue isomer were precipitated.
The mother liquor provides mainly the blue isomer.
Isomers were isolated by column chromatography on
alumina.
3.2. Crystal structures
The molecular structures of green tcc isomer (a) and
blue ccc isomer (b) are shown in Figs. 1 and 2, and
selected bond parameters are listed in Tables 2 and 3,
respectively. The coordination geometry around ruthe-
nium is distortedly octahedral. The atomic arrangement
in the green isomer (a) involves sequentially two trans-
chlorine, cis-isoquinoline-N (N) and cis-azo-N (N?) and
corresponds to a tcc configuration. Similarly, the
arrangement in blue isomer is ccc.
3.3. Green tcc-isomer (a)
Fig. 2. Molecular structure and atom-labeling scheme for the crystal
structure of blue ccc-isomer (b), excluding the solvents.
The ruthenium ion of the green crystal is six-
coordinated. The coordination geometry of rutheniu-
m(II) for this green isomer is distortedly octahedral with
surrounding N1, N3, N4, N6 atoms equatorial (rms
N(3), N(4) and Ru, Cl(1), Cl(2), N(1), N(6) constitute
˚
two good planes (rms deviation, 0.09 A) and are almost
orthogonal to the third molecular plane, Ru, N(1), N(3),
˚
deviation of 0.068 A) and Cl1, Cl2 atoms axial
˚
2.3798(12) and 2.3436(13) A, respectively, from the
(ꢃ
/
basal plane). The two atomic groups Ru, Cl(1), Cl(2),
Table 2
˚
Selected bond lengths (A) and angles (8) for green tcc-isomer (a)
Bond lengths
Ruꢀ
Ruꢀ
Ruꢀ
Ruꢀ
Ruꢀ
Ruꢀ
N(1)ꢀ
N(4)ꢀ
/
N(1)
N(4)
N(3)
N(6)
Cl(2)
Cl(1)
1.9851(19)
1.9952(19)
2.1009(19)
2.103(2)
/
/
/
/
2.3640(7)
2.3837(7)
1.295(3)
/
/N(2)
/N(5)
1.293(3)
Bond angles
N(1)ꢀRuꢀ
N(1)ꢀRuꢀ
N(4)ꢀRuꢀ
N(1)ꢀRuꢀ
N(4)ꢀRuꢀ
N(3)ꢀRuꢀ
N(1)ꢀRuꢀ
N(4)ꢀRuꢀ
N(3)ꢀRuꢀ
N(6)ꢀRuꢀ
N(1)ꢀRuꢀ
N(4)ꢀRuꢀ
N(3)ꢀRuꢀ
N(6)ꢀRuꢀ
Cl(2)ꢀRuꢀ
/
/
N(4)
N(3)
N(3)
N(6)
N(6)
N(6)
Cl(2)
Cl(2)
Cl(2)
Cl(2)
Cl(1)
Cl(1)
Cl(1)
Cl(1)
104.10(8)
75.36(8)
175.79(8)
176.41(7)
75.11(8)
105.69(8)
93.75(6)
93.14(6)
82.75(6)
89.80(6)
92.63(6)
93.83(6)
90.37(6)
83.95(6)
169.13(2)
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
Fig. 1. Molecular structure and atom-labeling scheme for the crystal
structure of green tcc-isomer (a), with solvent of dichloromethane.
/
/Cl(1)

T.-H. Lu et al. / Polyhedron 22 (2003) 535Á
/541
539
phenyl rings are planar (rms deviations of 0.006 and
˚
Table 3
˚
0.005 A) and intersect at an angle of 27.07(11)8 to each
other. The two cis-isoquinolines are planar (rms devia-
Selected bond lengths (A) and angles (8) for blue ccc-isomer (b)
Bond lengths
˚
tions of 0.0103 and 0.0273 A) and are almost parallel to
each other (dihedral angle, 2.89(14)8). The solvent of
dichloromethane is disordered in this green crystal.
Ruꢀ
Ruꢀ
Ruꢀ
Ruꢀ
Ruꢀ
Ruꢀ
N(1)ꢀ
N(4)ꢀ
/
N(4)
N(1)
N(3)
N(6)
Cl(2)
Cl(1)
1.968(3)
2.003(3)
2.018(3)
2.055(3)
2.3833(12)
2.3997(12)
1.306(4)
1.298(4)
/
/
/
/
3.4. Blue ccc-isomer (b)
/
/
N(2)
N(5)
Similar to the green isomer, the ruthenium ion of the
blue crystal is six-coordinated, and the coordination
geometry of ruthenium(II) for the blue isomer is also
distorted octahedron with Cl(2), N(1), N(3) and N(6)
/
Bond angles
N(4)ꢀRuꢀ
N(4)ꢀRuꢀ
N(1)ꢀRuꢀ
N(4)ꢀRuꢀ
N(1)ꢀRuꢀ
N(3)ꢀRuꢀ
N(4)ꢀRuꢀ
N(1)ꢀRuꢀ
N(3)ꢀRuꢀ
N(6)ꢀRuꢀ
N(4)ꢀRuꢀ
N(1)ꢀRuꢀ
N(3)ꢀRuꢀ
N(6)ꢀRuꢀ
Cl(2)ꢀRuꢀ
/
/
N(1)
N(3)
N(3)
N(6)
N(6)
N(6)
Cl(2)
Cl(2)
Cl(2)
Cl(2)
Cl(1)
Cl(1)
Cl(1)
Cl(1)
102.50(12)
98.13(12)
77.17(12)
76.31(12)
176.73(11)
99.92(12)
87.56(9)
99.54(8)
173.91(9)
83.48(8)
170.99(9)
86.22(8)
85.91(9)
95.11(8)
88.77(4)
/
/
˚
atoms basal (rms deviation of 0.0602 A), and Cl(1) and
/
/
˚
2.3560(18) and 1.9500(32) A, respectively,
/
/
N(4) apical (ꢃ
/
/
/
from the equatorial plane). The atomic groups Ru,
˚
N(1), N(3), Cl(2) (rms deviation, 0.041 A) and Ru, N(4),
˚
N(6), Cl(1) (rms deviation, 0.022 A) constitute two
almost orthogonal (dihedral angle, 87.87(6)8) planes.
The third plane, Ru, Cl(1), Cl(2), N(3), N(4) (rms
˚
deviation, 0.093 A), is less orthogonal (dihedral angles,
84.73(10)8 and 83.26(10)8, respectively, with the earlier
two planes). The trans angles around the ruthenium
center in the planes range from 170.99(9)8 to 176.73(7)8,
indicating distortion from rectilinear geometry. The
chelate rings, Ru, N(1), N(2), C(7), N(3) (rms deviation,
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/Cl(1)
˚
0.062 A) and Ru, N(4), N(5), N(6), C(22) (rms devia-
˚
tion, 0.076 A), are planar and their dihedral angle is
˚
N(4), N(6) (rms deviation, 0.06 A). The Ru atom is
˚
shifted by 0.005 A from the third plane towards Cl(1).
˚
76.67(10) A. Their chelate angles are considerably
The N(1)ꢀRuꢀN(6) angle is 176.41(7)8 which is dis-
/
/
deviated from ideal octahedral geometry. It is interesting
that most of the distortions away from octahedral
positions arising out of the larger angular distortions
are associated with the azo nitrogens rather than the
torted from linearity by 3.68. This deviation is quite
similar to that of tcc-Ru(aai)2Cl2 [1] and tcc-
Ru(papm)2Cl2 [3] and the reason is undoubtedly from
the acute (75.36(8)8) chelate bite angle [1]. The chelate
ring, Ru, N(1), N(2), C(7), N(3), is planar (rms
isoquinoline nitrogens, [N(3)ꢀ
N(1)ꢀRuꢀN(4), 102.50(12)8]. The cis-chloro angle of
88.77(4)8 is very nearly the ideal octahedral angle and is
comparable to reported values [1,3]. The NꢀN distances
of 1.306(4) and 1.298(4) A are longer than those in its
/
RuꢀN(6), 99.92(12)8;
/
/
/
˚
deviation, 0.083 A) and is similar to the other planarity
˚
of Ru, N(4), N(5), C(22), N(6) (rms deviation, 0.086 A)
/
˚
and their interplanar angle is 6.858. The trans-chlorine
angle is 169.13(2)8 which is essentially equivalent to the
reported values [1,3]. The structure of the molecule is
shown in Fig. 1 and the geometrical parameters are
listed in Tables 2 and 3 for isomers (a) and (b),
respectively.
˚
green counterpart of 1.295(3) and 1.293(3) A. The Ruꢀ
/
˚
N(azo) distances (1.968(3), 2.003(3) A) are shorter than
˚
N (isoquinoline) (2.018(3), 2.055(3) A) and
those of Ruꢀ
/
this is an indication of an MꢀL p-interaction that is
/
localized in the M-azo fragment. The two pendant
phenyl rings are planar (rms deviations of 0.009 and
The Ruꢀ
/
N?[N(azo): N(1) or N(4)] bond length
˚
˚
(average, 1.990(2) A) is shorter than the Ruꢀ
/N[N(iso-
0.003 A) and intersect at an angle of 68.15(14)8. The two
cis-isoquinolines are planar (rms deviations of 0.009 and
˚
quinoline): N(3) or N(6)] [average, 2.102(2) A] bond
˚
distance by 0.112 A. The shortening may be due to
˚
0.020 A) and intersect at an angle of 68.95(10)8. It is
greater p-backbonding, d(Ru)0
/
p*(azo) [1,3]. In this
interesting to note that this ccc-conformation is quite
different from the tcc one on the planarity of both cis-
isoquinolines and cis-phenyl rings. The ccc configura-
tion has a greater dihedral angle than the tcc scheme for
both isoquinolines. The dihedral angles between the
chelate ring and the corresponding phenyl ring are
˚
complex, the average NꢀN distance is 1.294(3) A which
/
is shorter than some reported values of free azo ligands
[28,29] and essentially equivalent to that of tcc-
Ru(aai)2Cl2 [1] and tcc-Ru(papm)2Cl2 [3]. The coordi-
nation leads to a decrease in the Nꢀ
/
N bond order due to
both s-donor and p-acceptor character of the ligand,
the later character having a more pronounced effect and
possibly being the reason of elongation. The two cis-
38.15(18)8 and 47.31(13)8. The Ruꢀ
/
Cl distance is
comparable with the reported values [1,3]. The solvents
of water, benzene and ethanol exist in the blue crystal.

540
T.-H. Lu et al. / Polyhedron 22 (2003) 535Á541
/
Table 4
Some selected bond lengths for related complexes
Compound
Ruꢀ/Cl(1)
Ruꢀ/Cl(2)
Ruꢀ/Nazo(1)
Ruꢀ
/
Nazo(2)
Ruꢀ/N(1)
RuꢀN(2)
/
a
tcc-Ru(paiq)2Cl2
ccc-Ru(paiq)2Cl2
2.364(7)
2.383(1)
2.382(2)
2.392(2)
2.363(1)
2.394(1)
2.368(2)
2.397(1)
2.401(2)
2.384(7)
2.399(1)
2.382(2)
2.407(2)
2.401(1)
2.401(1)
2.3768(1)
2.401(1)
2.410(3)
1.985(2)
1.968(3)
2.016(3)
1.991(4)
2.000(3)
1.971(3)
1.986(5)
1.977(4)
1.96(1)
1.995(2)
2.003(3)
2.016(3)
1.987(4)
2.005(3)
2.014(3)
1.988(5)
1.984(4)
1.9589(9)
2.101(2)
2.018(3)
2.063(3)
2.033(4)
2.072(3)
2.027(3)
2.099(5)
2.045(4)
2.028(9)
2.103(2)
2.055(3)
2.063(3)
2.043(4)
2.093(3)
2.047(3)
2.116(5)
2.051(4)
2.069(9)
a
tcc-Ru(aai-Bz)2Cl2 [1]
ctc-Ru(aai-Me)2Cl2 [1]
tcc-Ru(papm)2Cl2 [3]
ccc-Ru(papm)2Cl2 [3]
tcc-Ru(azpy)2Cl2 [22]
ctc-Ru(azpy)2Cl2 [23]
ccc-Ru(azpy)2Cl2 [23]
a
The present work.
There is one hydrogen bond between a water molecule
no. NSC 91-2112-M-007-055) and to C.-S.C. (grant no.
NSC 91-2113-M-007-051).
and ethanol. Its bond distance and bond angle of O(1)ꢀ
/
˚
H(41)Á Á ÁOw are 2.823 A and 128.698, respectively. The
center of the benzene ring is located at an inversion
center so that only three atoms of the ring have to be
determined. Consequently, the six atoms of the ring are
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