Synthesis, structure, and reactivities of the Ru-Co heterobimetallic complex

Article abstract of DOI:10.1016/S0022-328X(99)00608-7

Treatment of Cp*Ru(CO)₂Cl (Cp* = η⁵-C₅Me₅) with NaCo(CO)₄ produces the metal-metal bonded heterobimetallic complex Cp*Ru(CO)₂(μ₂-CO)Co(CO)₃ (2b). Substitution of the CO ligands by the Ph₂PCH₂PPh₂ (dppm) leads to the isolation of Cp*Ru(μ₂-CO)₂(μ₂-dppm)Co(CO) ₂ (3) whereas that by Bu^tNC gives Cp*Ru(CO)(CNBu^t)(μ₂-CO)Co(CO)₃ (4). Stoichiometric head-to-tail dimerization of p-tolylacetylene at the bimetallic site of 2b proceeds to form the dinuclear metallacyclopentadiene complex Cp*(CO)Ru{η²:η⁴-μ ₂-C(Tol)CHC(Tol)CH}Co(CO)₂ (5) in which two alkyne molecules are coupled to form a ruthenacyclopentadiene core which coordinates to the Co(CO)₂ fragment. On the other hand, catalytic head-to-head coupling of methyl propiolate in the presence of 2b yields (E)-(MeO₂C)CH=CH(C=CCO₂Me) (6). The molecular structures of 2b, 3, 4, and 5 have been determined by X-ray crystallography.

Full text of DOI:10.1016/S0022-328X(99)00608-7

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 596 (2000) 121–129
Synthesis, structure, and reactivities of the Ru–Co heterobimetallic
complex. Molecular structures of Cp*Ru(CO)2(m2-CO)Co(CO)3,
Cp*Ru(m2-CO)2(m2-dppm)Co(CO)2,
Cp*Ru(CNBut)(CO)(m2-CO)Co(CO)3, and
Cp*(CO)Ru{h2:h4–m2–C(Tol)CHC(Tol)CH}Co(CO)2
(Cp*=h5-C5Me5, dppm=Ph2PCH2PPh2, Tol=C6H4Me-4)
Hiroyuki Matsuzaka *, Koji Ichikawa, Tomohiro Ishioka, Haru Sato, Takashi Okubo,
Tomohiko Ishii, Masahiro Yamashita, Mitsuru Kondo1, Susumu Kitagawa 1
Department of Chemistry, Graduate School of Science, Tokyo Metropolitan Uni6ersity, Minami-osawa, Hachioji, Tokyo 192-0397, Japan
Received 12 August 1999
Abstract
Treatment of Cp*Ru(CO)2Cl (Cp*=h5-C5Me5) with NaCo(CO)4 produces the metal–metal bonded heterobimetallic complex
Cp*Ru(CO)2(m2-CO)Co(CO)3 (2b). Substitution of the CO ligands by the Ph2PCH2PPh2 (dppm) leads to the isolation of
Cp*Ru(m2-CO)2(m2-dppm)Co(CO)2 (3) whereas that by ButNC gives Cp*Ru(CO)(CNBut)(m2-CO)Co(CO)3 (4). Stoichiometric
head-to-tail dimerization of p-tolylacetylene at the bimetallic site of 2b proceeds to form the dinuclear metallacyclopentadiene
complex Cp*(CO)Ru{h2:h4-m2-C(Tol)CHC(Tol)CH}Co(CO)2 (5) in which two alkyne molecules are coupled to form a ruthenacy-
clopentadiene core which coordinates to the Co(CO)2 fragment. On the other hand, catalytic head-to-head coupling of methyl
propiolate in the presence of 2b yields (E)-(MeO2C)CHꢀCH(CꢁCCO2Me) (6). The molecular structures of 2b, 3, 4, and 5 have
been determined by X-ray crystallography. © 2000 Elsevier Science S.A. All rights reserved.
Keywords: Heterobimetallic complex; Ruthenium; Cobalt; Alkyne; Dinuclear metallacyclopentadiene; Enyne
reported by Joshi and Pauson [2], and the molecular
structures of 1a [3] and (indenyl)Fe(CO)(m2-CO)2-
Co(CO)3 [4] have been established. Subsequent studies
revealed that the CO ligands terminally bonded to the
Co atom in 1a were selectively substituted by PMePh2
or dienes to give CpFe(CO)(m2-CO)2Co(CO)2(PMePh2)
[5], CpFe(CO)(m2-CO)2Co(CO)(CH2ꢀCMeCMeꢀCH2)
[6], and CpFe(CO)(m2-CO)2Co(CO)(norbornadiene) [7],
respectively. In sharp contrast, the chemistry of
CpRu(CO)2Co(CO)4 (2a) has been surprisingly less de-
veloped to date, partially because 2a can be isolated
only in very poor yield (ca. 10%) [8]. We have recently
found that Cp*Ru(CO)2(m2-CO)Co(CO)3 (2b), the Cp*
analog of 2a, is readily obtained in high yield [9], which
prompted us to investigate its chemical reactivity. Here
we describe details on preparation and structure of 2b
1. Introduction
The chemistry of heteronuclear metal–metal bonded
compounds has been a major subject of recent research
interest due to the inherent catalytic potential of
mixed–metal complexes [1]. The Fe–Co heterobimetal-
lic complex CpFe(CO)(m2-CO)2Co(CO)3 (1a; Cp=h5-
C5H5), one of the examples of this class, was originally
* Corresponding author. Tel.: +81-426-77-2551; fax: +81-426-77-
2525.
E-mail addresses: matsuzaka-hiroyuki@c.metro-u.ac.jp (H. Mat-
suzaka), kitagawa@sbchem.kyoto-u.ac.jp (S. Kitagawa)
1 Present address: Department of Synthetic Chemistry and Biologi-
cal Chemistry, Graduate School of Engineering, Kyoto University,
Sakyo-ku, Kyoto 606-8501, Japan. Tel.: +81-75-753-5652; fax: +
81-75-753-4979.
0022-328X/00/$ - see front matter © 2000 Elsevier Science S.A. All rights reserved.
PII: S0022-328X(99)00608-7

122
H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
together with its phosphine and isocyanide substituted
derivatives Cp*Ru(m2-CO)2(m2-dppm)Co(CO)2 (3; dppm
=Ph2PCH2PPh2) and Cp*Ru(CO)(CNBut)(m2-CO)Co-
(CO)3 (4). Also reported is the dimerization reaction of
terminal alkynes induced by 2b, which selectively af-
fords either the dinuclear metallacyclopentadiene com-
complex Cp*Fe(CO)(m2-CO)2Co(CO)3 (1b, 39%), which
was recently isolated by Akita et al. as one of the
thermolysis products of the trinuclear cluster (h2:h2-m2-
Fp*CꢁCH)Co2(CO)6 (Fp*=Cp*Fe(CO)2) and has
been structurally defined [11].
An ORTEP drawing of 2b is depicted in Fig. 1, and
selected bond distances and angles are given in Table 2.
Fig. 1 clearly shows the dinuclear structure of 2b where
the Cp*Ru(CO)2 unit and the Co(CO)4 fragment are
plex
Cp*(CO)Ru{h2:h4-m2-C(Tol)CHC(Tol)CH}Co-
(CO)2 (5) or (E)-enyne (E)-(MeO2C)CHꢀCH(CꢁCCO2-
Me) (6) depending upon the nature of the alkyne.
,
joined by the direct Ru–Co bond (2.7445(6) A), the
distance of which is in the range of a typical Ru–Co
,
2. Results and discussion
single bond (2.59–2.79 A) [12]. The semi-bridging
C(3)O(3) ligand is bonded more strongly to Co than to
,
,
A yellow–brown THF solution of Cp*Ru(CO)2Cl
gradually turned to an orange suspension upon treat-
ment with NaCo(CO)4 (one equivalent) over 4 days at
50°C. Work-up of the reaction mixture resulted in the
isolation of Cp*Ru(CO)2(m2-CO)Co(CO)3 (2b) as an
orange microcrystalline solid (86%, Scheme 1), which
was both spectroscopically and crystallographically
Ru [Co(1)–C(3), 1.817(4) A; Ru(1)–C(3), 2.206(3) A]
and the O(3) atom is tilted towards Ru [Co(1)–C(3)–
O(3), 148.5(3)°; Ru(1)–C(3)–O(3), 126.3°]. The bond-
ing mode of the m2-CO ligand in 2b is in sharp contrast
to that observed in 1b [11]. Thus, the semi-bridging CO
ligand in 1b is bonded more strongly to Fe than to Co
,
,
(Fe–C, 1.834(3) A; Co–C, 2.225(3) A] and the oxygen
atom is tilted toward Co [Fe–C–O, 153.3(3)°; Co–C–
O, 128.0(2)°]. Complex 1b has another m2-CO which is
coordinated to Fe and Co in an essentially symmetrical
manner.
Treatment of 2b with Ph2PCH2PPh2 (dppm, one
equivalent) and Me3NO·2H2O (one equivalent) in
refluxing THF produced Cp*Ru(m2-CO)2(m2-dppm)-
Co(CO)2 (3, 79%, Scheme 1), which was isolated as
orange columnar crystals and both spectroscopically
and crystallographically characterized. The 1H-NMR
spectrum of 3 shows a triplet due to the methylene
protons of dppm at l 2.15, together with signals at-
tributed to the Cp* (l 1.59) and phenyl protons. The
31P{1H}-NMR spectrum of 3 exhibits two resonances at
l 55.1 (Ru–P) and 42.1 (Co–P). The latter signal is
1
characterized. The H-NMR spectrum of 2b shows a
characteristic resonance of Cp* protons at l 1.94. The
IR spectrum indicates the presence of terminal and
bridging CO ligands both in the solid state and in THF
solution [10]. This is in sharp contrast with the fact that
all CO ligands in 2a are terminally bonded to the metal
atoms [8]. The mass spectrum (FAB) of 2b shows a
parent ion peak at m/z=464 {(M+1)+} together with
resonances due to the sequential loss of six CO groups.
These spectral data are fully consistent with the crystal
structure of 2b (vide infra). It is interesting to note that
the reaction of Cp*Ru(CO)2Cl with NaCo(CO)4 readily
afforded 2b (86%), whereas that of CpRu(CO)2Cl gave
2a only in very low yield (10%) [8b]. Treatment of
Cp*Fe(CO)Cl with NaCo(CO)4 produced the related
Scheme 1.

H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
123
Fig. 1. Molecular structure of 2b drawn at the 50% probability level.
Fig. 2. Molecular structure of 3 drawn at the 50% probability level.
markedly broader than the former one owing to the
effects of the quardrupole monent of the cobalt nucleus
to which it is directly bonded. The IR spectrum of 3
indicates the existence of both terminal (wCO 1985, 1932
cm−1) and bridging (wCO 1728 cm−1) CO ligands.
These spectral data are fully consistent with its crystal
structure depicted in Fig. 2. The dppm ligand bridges
the two metal atoms to form the common five-mem-

124
H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
bered framework. The C(4)O(4) ligand bridges Ru and
Co in an essentially symmetrical manner as is evident
from the similar M–C(4) distances [Ru(1)–C(4),
tains two crystallographically independent formula
units. An ORTEP drawing of them is given in Fig. 3,
which clearly shows that the ButNC ligand coordinates
to Ru and occupies the pseudo-cis position to the
m2-CO unit in both molecules.
,
,
2.014(4) A; Co(1)–C(4), 1.958(4) A] and M–C(4)–O(4)
angles [Ru(1)–C(4)–O(4), 137.7(4)°; Co(1)–C(4)–O(4),
137.7(3)°]. On the other hand, the C(3)O(3) group is
bonded more strongly to Ru than to Co [Ru(1)–C(3),
Complex 2b reacted with HCꢁCTol (five equivalents)
in the presence of Me3NO·2H2O to yield the dinuclear
metallacyclopentadiene complex Cp*(CO)Ru{h2:h4-m2-
C(Tol)CHC(Tol)CH}Co(CO)2 (5) (95%, Scheme 1),
which was isolated as orange columnar crystals and
spectroscopically characterized. The molecular struc-
ture of 5 has been further defined by X-ray crystallogra-
,
,
1.917(5) A; Co(1)–C(3), 2.226(5) A] and the O(3) atom
is tilted toward Co [Ru(1)–C(3)–O(3), 149.9(4)°;
Co(1)–C(3)–O(3), 129.9(4)°]. These bridging modes of
two m2-CO ligands are similar to those observed for 1b
(vide supra) [11]. The intramolecular distance between
Ru and Co is 2.6733(7) A, which indicates a direct
phy. The 1H-NMR spectrum of
5 exhibits two
,
4
bonding interaction between the two metal atoms [12].
Substitution of the CO ligand in 2b also proceeded
with ButNC (five equivalents) in the presence of
Me3NO·2H2O (one equivalent) to form the monosubsti-
tuted species Cp*Ru(CO)(CNBut)(m2-CO)Co(CO)3 4,
which was isolated as orange needles and both spectro-
scopically and crystallographically characterized. The
1H-NMR spectrum of 4 shows two singlets at l 1.44
(9H, But) and 1.87 (15H, Cp*). The IR spectrum of 4
resonances at l 8.00 and 6.90 (d, 1H each, JHH=2.5
Hz) due to the Ha and Hb protons (Scheme 1) of the
metallacyclopentadine framework. An ORTEP drawing
of 5 is shown in Fig. 4, and selected bond distances and
angles are given in Table 5. Two HCꢁCTol molecules
are coupled in a head-to-tail manner on the bimetallic
site to form the ruthenacyclopentadiene core which is
coordinated to the Co(CO)2 fragment. The four carbon
atoms C(1)–C(4) are essentially coplanar. However, the
metallacycle ring in 5 is not planar as commonly ob-
served for other dinuclear metallacyclopentadiene sys-
tems [13] but is bent with a fold angle of 17.7° (angle
between the Ru(1)–C(1)–C(4) and C(1)–C(2)–C(3)–
C(4) planes). Examples containing the folded five-mem-
bered rings are still limited.[14]. The distance between
exhibits wCO resonances at 2027, 1956, and 1794 cm−1
,
which are lower by approximately 20 cm−1 compared
with those observed for the parent 2b. The key to the
structural assignment of 4 from the IR spectrum is the
absence of a set of two resonances due to the symmetric
and anti symmetric stretching of two CO groups termi-
nally bonded to Ru in cis configuration. These spectral
data indicate that one of the two COs terminally
bonded to Ru is selectively substituted by the ButNC
ligand (Scheme 1), which is unambiguously confirmed
by X-ray diffraction analysis. The crystal lattice con-
,
the two metal atoms in 5 is 2.627(1) A, indicating the
existence of a Ru–Co single bond.[12].
On the other hand, reaction of 2b with HCꢁCCO2Me
occurred in a quite different manner. Thus, catalytic
head-to-head dimerization of the alkyne readily pro-
Fig. 3. Molecular structure of 4 drawn at the 50% probability level.

H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
125
Fig. 4. Molecular structure of 5 drawn at the 50% probability level.
ceeded at 50°C in the presence of 5 mol% of 2b and
Me3NO·2H2O to give (E)-(MeO2C)CHꢀCH(CꢁCCO2-
Me) (6, 43%) together with (E,E)-(MeO2C)CHꢀ
CHOCHꢁCH(CO2Me) (7, 7%), both of which were
isolated as white microcrystalline solids and spectroscop-
ically characterized (Eq. (1)).
tial for this dimerization. Only a trace amount of
cyclotrimerization products were detected when the reac-
tion was carried out without Me3NO·2H2O. The di-
alkenyl ether 7 can be formally derived from two alkyne
molecules and H2O. In fact, the yield of 7 was increased
up to 29% when the reaction was carried out in the
presence of a stoichiometric amount of H2O (50 mol%
of the alkyne), whereas the reaction in the presence of
carefully dried Me3NO gave only 1% of 7. These results
suggest that H2O plays a critical role in the formation of
7. However we must await further investigation to
elucidate the detailed reaction mechanism. It is not
certain at this stage whether a heterobimetallic complex
2b or a mononuclear species derived from 2b is the active
catalyst. The 1H-NMR analysis indicated the absence of
2b in the crude reaction mixture but several Cp* reso-
nances were also observed around l 2 ppm.
(1)
It is of interest to note that carbon–carbon bond
formation between the alkyne molecules exclusively pro-
duces 6 and neither the corresponding (Z)-enyne nor the
head-to-tail dimers were detected during this reaction.
Several examples of selective head-to-head coupling of
terminal alkynes to form trans-enynes have appeared in
the literature [15]. There is great interest at the present
time in head-to-head, tail-to-tail and head-to-tail cou-
pling of alkyne and alkynyl groups at bimetallic and
polymetallic centers because of the possibility of generat-
ing new molecular wires and molecular switches. The
role of the metals and orientation of the yne (ynyl)
functionality at the metal centers in directing such
coupling reactions is crucial [16]. It is noteworthy that
cyclotrimerization of HCꢁCCO2Me did not proceed
under these conditions. This is the most commonly
observed coupling product in transition metal-catalyzed
oligomerization of alkynes [17]. Me3NO·2H2O is essen-
3. Experimental
3.1. General
Complexes Cp*Ru(CO)2Cl [18] and NaCo(CO)4 [19]
were prepared according to the published methods. The
reagents ButNC, HCꢁCTol, and HCꢁCCO2Me were
,
obtained commercially, degassed, and stored over 4 A
molecular sieves, whereas dppm was obtained commer-
cially and used without further purification. Solvents

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H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
were dried by refluxing over Na–benzophenone ketyl
(THF, benzene, hexane), or CaH2 (CH2Cl2) and freshly
distilled prior to use. All manipulations were per-
formed with standard Schlenk tube techniques. IR
spectra were recorded on a Hitachi I-5040 spectrome-
ter. NMR spectra were obtained on a JEOL Lambda-
500 spectrometer, and mass spectra were recorded on a
JEOL AX-505H spectrometer. Elemental analyses were
performed at the Elemental Analysis Laboratory, De-
partment of Chemistry, Tokyo Metropolitan Univer-
sity.
tallized from benzene–hexane to afford 3 as orange
columnar crystals (251 mg, 79%). H-NMR (C6D6) l
1
7.49–6.95 (m, 20H, Ph), 2.15 (t, 2H, 2JPH=9.2 Hz,
PCH2P), 1.59 (s, 15H, Cp*). IR (THF, cm−1) wCO
1985(s), 1932(s), 1728(m). 31P{1H}-NMR l 55.1(d,
2JPP=101 Hz, Ru–P), 42.1 (brs, Co–P). Anal. Found:
C, 59.19; H, 4.80. Calc. for C39H37CoO4P2Ru: C,
59.16; H, 4.71%.
3.5. Reaction of 2b with ButNC
To a mixture of 2b (87 mg, 0.19 mmol) and
Me3NO·2H2O (21 mg, 0.19 mmol) in THF (10 ml) was
added ButNC (79 mg, 0.95 mmol) and the solution was
stirred for 6 h at room temperature. After removal of
the solvent, the residue was purified by chromatogra-
phy on alumina with 3:7 benzene–hexane. Evaporation
of the solvent from a single yellow band gave a yellow
solid which was recrystallized from hexane to afford 4
3.2. Preparation of 2b
To a THF (10 ml) solution of Cp*Ru(CO)2Cl (1.425
g, 4.346 mmol) was added NaCo(CO)4 (0.843 g, 4.346
mmol) in THF (20 ml) and the reaction mixture was
stirred for 4 days at 60°C, during which time the
original yellow–brown solution gradually turned to a n
orange suspension. After removal of the solvent, the
resulting residue was extracted with hexane and
purified by chromatography on alumina with benzene/
hexane (3/7). Evaporation of the solvent from a single
orange band gave 2b as an analytically pure orange
microcrystalline solid (1.73 g, 86%). Complex 2b was
quite soluble in common organic solvents. Single crys-
tals suitable for X-ray diffraction analysis were
1
as orange needles (64 mg, 65%). H-NMR (CDCl3) l
1.87 (s, 15H, Cp*), 1.44 (s, 9H, But). IR (THF, cm−1):
wNC 2145, wCO 2027(s), 1956(s), 1794(w). Anal. Found:
C, 46.15; H, 4.41; N, 2.54. Calc. for C20H24CoNO5Ru:
C, 46.33; H, 4.67; N, 2.70%.
3.6. Reaction of 2b with HCꢁCTol
1
obtained by recrystallization from MeOH–water. H-
Complex 2b (306 mg, 0.660 mmol) was reacted with
a mixture of HCꢁCTol (372 mg, 3.20 mmol) and
Me3NO·2H2O (73 mg, 0.660 mmol) in THF at 60°C
for 12 h. After removal of the solvent, the residue was
purified by chromatography on alumina with hexane.
Evaporation of the solvent from a single orange band
afforded 5 as an orange microcrystalline solid (95%).
Single crystals for structural analysis were prepared by
recrystallization from hexane. 1H-NMR (CDCl3) l
8.00 (d, 1H, J=2.5 Hz, Ha), 7.47, 7.37 (d, 2H each,
J=8.2 Hz, aryl), 7.14–7.12 (m, 4H, aryl), 6.90 (d, 1H,
J=2.5 Hz, Hb), 2.37, 2.34 (s, 3H each, C6H4Me), 2.02
(s, 15H, Cp*). IR (hexane): wCO 2010 (vs), 1970 (vs),
1956 (vs). Anal. Found: C, 61.31; H, 5.24. Calc. for
C31H31CoO3Ru: C, 60.87; H, 5.11%.
NMR (CDCl3) l 1.94(s, Cp*). IR (THF, cm−1): wCO
2053(s), 2004(s), 1971(s), 1817(w). MS(FAB), m/z=
464 {(M+1)+}. Anal. Found: C, 41.67; H, 3.51. Calc.
for C16H15CoO6Ru: C, 41.47; H, 3.26%.
3.3. Preparation of 1b
Cp*Fe(CO)2Cl was prepared in 79% yield by
analogous procedures to those reported for Cp-
1
Fe(CO)2Cl [20]. H-NMR (CDCl3) l 1.77(s, Cp*). IR
(THF, cm−1): wCO 2024(s), 1973(s). To a THF (20 ml)
solution of Cp*Fe(CO)2Cl (320 mg, 1.13 mmol) was
added NaCo(CO)4 (220 mg, 1.13 mmol) and the mix-
ture was stirred overnight at 50°C. After removal of
the solvent, the residue was extracted with benzene and
chromatographed on silica gel with benzene. Evapora-
tion of the solvent from a single orange band afforded
1b as a dark brown microcrystalline solid (184 mg,
39%).
3.7. Reaction of 2b with HCꢁCCO2Me
A THF (20 ml) solution containing 2b (95 mg, 0.21
mmol), Me3NO·2H2O (23 mg, 0.21 mmol), and
HCꢁCCO2Me (353 mg, 4.20 mmol) was stirred at 50°C
for 96 h. After removal of the solvent, the residue was
chromatographed on silica gel first with CH2Cl2 to
elute 6 then with 1:3 THF–hexane to elute 7. Evapora-
tion of the solvent gave 6 (152 mg, 43%) and 7 (27 mg,
3.4. Reaction of 2b with dppm
To a THF (10 ml) solution of 2b (185 mg, 0.399
mmol) was added Me3NO·2H2O (44 mg, 0.399 mmol)
and dppm (153 mg, 0.399 mmol) and the solution was
refluxed overnight. After removal of the solvent, the
resulting residue was extracted with benzene. Removal
of the solvent gave an orange solid which was recrys-
1
7%), respectively. 7: H-NMR (CDCl3) l 7.58, 5.66 (d,
2H each, J=12.2 Hz, alkenyl), 3.74 (s, 6H, OMe).
13C-NMR (CDCl3) l 166.4 (CO), 157.3 (–O–CꢀC),
104.0 (–O–CꢀC), 51.6 (OMe). IR (KBr: cm−1): wCO

H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
127
Table 1
Crystal and data collection parameters for complexes 2b, 3, 4, and 5
2b
3
4
5
Formula
C
16H15O6CoRu
C39H37O4P2CoRu
791.67
P21/a (monoclinic)
Orange
C40H48Co2N2O10Ru2
1036.83
Pca21 (orthorombic)
Orange
C31H31O3CoRu
611.59
Molecular weight
Space group (crystal system)
Crystal color
463.29
P1 (triclinic)
Orange
(
P1 (triclinic)
Dark orange
Unit cell dimensions
,
a (A)
9.219(2)
12.301(2)
8.4515(7)
90.94(1)
109.164(9)
90.63(1)
905.0(2)
2
17.284(2)
11.941(2)
17.678(2)
16.810(10)
8.634(7)
32.24(1)
10.681(3)
14.722(4)
9.443(2)
100.18(2)
99.42(2)
105.06(2)
1376.5(8)
2
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
105.687(8)
3
,
Cell volume (A )
3512.7(7)
4
1.497
4678(9)
4
1.472
Z
Dcalc (g cm−3
)
1.700
1.475
F(000) electrons
460
17.77
1616
10.33
2096
13.82
624
11.81
v(Mo–Ka)calc (cm−1
)
Crystal dimensions (mm)
Reflections measured
Used data (I=3|(I))
0.40×0.20×0.20
9h, +k, 9l
3829
0.30×0.30×0.20
+h, −k, 9l
4793
0.20×0.30×0.30
−h, +k,−l
2547
0.35×0.35×0.25
9h, +k, 9l
2683
No. of parameters refined
217
424
245
325
R
0.032
0.038
0.057
0.044
Rw
GoF
0.039
4.09
0.035
1.71
0.069
0.67
0.036
2.05
1717. MS (EI), 186 [M+]. Anal. Found: C, 51.81; H,
5.26. Calc. for C8H10O5: C, 51.61; H, 5.41%.
3.8. X-ray crystallography of 2b, 3, and 5
Table 2
a
,
Selected bond distances (A) and angles (°) for 2b
Suitable crystals of 2b, 3, 4, and 5 were mounted on
glass fibers. Diffraction measurements were made on a
Rigaku AFC-7R automated four-circle diffractometer
by using graphite-monochromated Mo–Ka radiation
Bond distances
Ru(1)–Co(1)
Ru(1)–C(2)
Ru(1)–C(7)
Ru(1)–C(9)
Ru(1)–C(11)
Co(1)–C(4)
Co(1)–C(6)
O(2)–C(2)
2.7445(6)
1.890(4)
2.281(3)
2.239(3)
2.239(3)
1.755(5)
1.806(5)
1.131(4)
1.141(5)
1.128(5)
Ru(1)–C(1)
Ru(1)–C(3)
Ru(1)–C(8)
Ru(1)–C(10)
Co(1)–C(3)
Co(1)–C(5)
O(1)–C(1)
O(3)–C(3)
O(5)–C(5)
1.899(4)
2.206(3)
2.258(3)
2.225(3)
1.817(4)
1.800(4)
1.136(4)
1.174(4)
1.133(5)
,
(w=0.71069 A). The unit cells were determined and
refined by a least-squares method using 20 independent
reflections. Data were collected with an ꢀ–2q scan
technique. If |(F)/F was more than 0.1, a scan was
repeated up to five times and the results were added to
the first scan. Three standard reflections were moni-
tored at every 150 measurements. All data processing
was performed on a Silicon Graphics Iris Indigo com-
O(4)–C(4)
O(6)–C(6)
Bond angles
Co(1)–Ru(1)–C(1) 68.3(1)
Co(1)–Ru(1)–C(3) 41.31(9)
C(1)–Ru(1)–C(3) 103.9(1)
Ru(1)–Co(1)–C(3) 53.3(1)
Ru(1)–Co(1)–C(5) 111.0(1)
C(3)–Co(1)–C(4)
C(3)–Co(1)–C(6)
C(4)–Co(1)–C(6)
Ru(1)–C(1)–O(1) 168.6(3)
Ru(1)–C(3)–Co(1) 85.4(1)
Co(1)–C(3)–O(3) 148.5(3)
Co(1)–C(5)–O(5) 175.5(4)
Co(1)–Ru(1)–C(2)
C(1)–Ru(1)–C(2)
C(2)–Ru(1)–C(3)
Ru(1)–Co(1)–C(4)
Ru(1)–Co(1)–C(6)
C(3)–Co(1)–C(5)
C(4)–Co(1)–C(5)
C(5)–Co(1)–C(6)
Ru(1)–C(2)–O(2)
Ru(1)–C(3)–O(3)
Co(1)–C(4)–O(4)
Co(1)–C(6)–O(6)
103.7(1)
90.8(2)
83.1(1)
129.4(2)
99.0(1)
103.3(2)
110.6(2)
105.1(2)
175.6(3)
126.0(3)
177.5(5)
176.8(5)
puter with the TEXSAN program (Rigaku, Tokyo).
Neutral scattering factors were obtained from the stan-
dard source [21]. In the reduction of data, Lorentz
polarization and empirical absorption corrections (c
scan) were made.
The structures were solved by a combination of
heavy-atom Patterson methods (2b, 5) or by direct
methods (SHELXL-86 for 3, SIR-92 for 4) and Fourier
synthesis (DIRDIF). All the non-hydrogen atoms were
refined anisotropically for 2b, 3, and 5. For 4, Ru and
Co atoms were refined anisotropically whereas other
non-hydrogen atoms were refined isotropically. All the
90.1(2)
146.2(2)
96.8(2)
a Estimated S.D.s in the least significant figure are given in paren-
theses.

128
H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
Table 3
Table 4
a
a
,
,
Selected bond distances (A) and angles (°) for 3
Selected bond distances (A) and angles (°) for 4
Bond distances
Bond distances
Ru(1)–Co(1)
Ru(1)–C(2)
Ru(1)–C(4)
Ru(1)–C(11)
Ru(1)–C(17)
Ru(2)–C(21)
Ru(2)–C(23)
Ru(2)–C(25)
Ru(2)–C(36)
Co(1)–C(17)
Co(1)–C(19)
Co(2)–C(37)
Co(2)–C(39)
2.735(4)
2.22(2)
2.28(2)
1.94(3)
2.10(3)
2.26(2)
2.19(2)
2.27(3)
1.80(2)
1.83(3)
1.70(3)
1.81(3)
1.69(3)
Ru(1)–C(1)
Ru(1)–C(3)
Ru(1)–C(5)
Ru(1)–C(16)
Ru(2)–Co(2)
Ru(2)–C(22)
Ru(2)–C(24)
Ru(2)–C(31)
Ru(2)–C(37)
Co(1)–C(18)
Co(1)–C(20)
Co(2)–C(38)
Co(2)–C(40)
2.21(2)
2.23(2)
2.26(2)
1.92(3)
2.743(4)
2.22(2)
2.25(2)
1.97(3)
2.12(3)
1.73(2)
1.74(2)
1.94(5)
1.76(5)
Ru(1)–Co(1)
Ru(1)–C(3)
Ru(1)–C(5)
Ru(1)–C(7)
Ru(1)–C(9)
Co(1)–C(1)
Co(1)–C(3)
O(1)–C(1)
2.6733(7)
1.917(5)
2.273(4)
2.256(4)
2.250(4)
1.768(5)
2.226(5)
1.149(5)
1.167(5)
Ru(1)–P(1)
Ru(1)–C(4)
Ru(1)–C(6)
Ru(1)–C(8)
Co(1)–P(2)
Co(1)–C(2)
Co(1)–C(4)
O(2)–C(2)
O(4)–C(4)
2.304(1)
2.014(4)
2.238(4)
2.270(4)
2.190(1)
1.749(5)
1.958(4)
1.157(5)
1.177(4)
O(3)–C(3)
Bond angles
Co(1)–Ru(1)–P(1)
Co(1)–Ru(1)–C(4) 46.8(1)
P(1)–Ru(1)–C(4)
Ru(1)–Co(1)–P(2)
93.91(3)
Co(1)–Ru(1)–C(3)
P(1)–Ru(1)–C(3)
C(3)–Ru(1)–C(4)
Ru(1)–Co(1)–C(1)
Ru(1)–Co(1)–C(3)
P(2)–Co(1)–C(1)
P(2)–Co(1)–C(3)
C(1)–Co(1)–C(2)
C(1)–Co(1)–C(4)
C(2)–Co(1)–C(4)
Ru(1)–P(1)–C(15)
Co(1)–C(1)–O(1)
Ru(1)–C(3)–Co(1)
Co(1)–C(3)–O(3)
Ru(1)–C(4)–O(4)
P(1)–C(15)–P(2)
55.1(1)
86.0(1)
100.1(2)
118.1(2)
44.9(1)
105.1(2)
86.6(1)
97.3(2)
160.6(2)
83.0(2)
112.7(1)
176.5(5)
80.0(2)
129.9(4)
137.7(4)
117.3(2)
84.8(1)
98.46(4)
Bond angles
Co(1)–Ru(1)–C(11) 101.7(8)
Co(1)–Ru(1)–C(17) 41.9(9)
C(11)–Ru(1)–C(17) 83(1)
Co(2)–Ru(2)–C(31) 100.1(7)
Co(2)–Ru(2)–C(37) 41.3(7)
C(31)–Ru(2)–C(37) 81(1)
Ru(1)–Co(1)–C(17) 50.1(9)
Ru(1)–Co(1)–C(19) 127(1)
C(17)–Co(1)–C(18) 144(1)
Co(1)–Ru(1)–C(16) 69.6(8)
C(11)–Ru(1)–C(16) 87(1)
C(16)–Ru(1)–C(17) 106(1)
Co(2)–Ru(2)–C(36) 70.5(7)
C(31)–Ru(2)–C(36) 87(1)
C(36)–Ru(2)–C(37) 106(1)
Ru(1)–Co(1)–C(18) 97.8(7)
Ru(1)–Co(1)–C(20) 111.9(7)
Ru(1)–Co(1)–C(2) 121.5(2)
Ru(1)–Co(1)–C(4) 48.6(1)
P(2)–Co(1)–C(2)
P(2)–Co(1)–C(4)
C(1)–Co(1)–C(3)
C(2)–Co(1)–C(3)
C(3)–Co(1)–C(4)
Co(1)–P(2)–C(15) 111.7(1)
Co(1)–C(2)–O(2) 177.4(4)
Ru(1)–C(3)–O(3) 149.9(4)
Ru(1)–C(4)–Co(1) 84.6(2)
Co(1)–C(4)–O(4) 137.7(3)
116.2(2)
91.9(1)
80.1(2)
156.6(2)
91.9(2)
C(17)–Co(1)–C(19)
C(18)–Co(1)–C(19)
91(1)
99(1)
C(17)–Co(1)–C(20)
C(18)–Co(1)–C(20) 110(1)
Ru(1)–C(17)–Co(1) 88(1)
99(1)
C(19)–Co(1)–C(20) 109(1)
Ru(1)–C(17)–O(2) 127(2)
Ru(1)–C(11)–N(1) 175(2)
Ru(2)–Co(2)–C(38) 100(1)
Ru(2)–Co(2)–C(40) 108(2)
Co(1)–C(17)–0(2)
145(3)
Ru(2)–Co(2)–C(37) 50.5(8)
Ru(2)–Co(2)–C(39) 125.0(9)
C(37)–Co(2)–C(38) 148(2)
a Estimated S.D.s in the least significant figure are given in paren-
theses.
C(37)–Co(2)–C(39)
C(38)–Co(2)–C(39)
92(1)
97(2)
C(37)–Co(2)–C(40)
99(2)
C(38)–Co(2)–C(40) 104(2)
Ru(2)–C(37)–Co(2) 88(1)
Co(2)–C(37)–O(7) 142(2)
C(39)–Co(2)–C(40) 117(2)
Ru(2)–C(37)–O(7) 129(2)
Ru(2)–C(31)–N(2) 178(2)
hydrogen atoms were fixed at the calculated positions
,
(C–H=0.95 A) and were not refined. The crystallo-
a Estimated S.D.s in the least significant figure are given in paren-
theses.
graphic data and selected structural parameters are
summarized in Tables 1–5.
Table 5
a
,
Selected bond distances (A) and angles (°) for 5
4. Supplementary material
Bond distances
Crystallographic data for the structures reported in
this paper have been deposited with the Cambridge
Crystallographic Data Centre, CCDC nos. 132706 for
2b, 132707 for 3, 134377 for 4, and 132708 for 5.
Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
Cambridge, CB2 1EZ, UK (Fax: +44-1223-336033;
e-mail: deposit@ccdc.cam.ac.uk or www: http://
www.ccdc.cam.ac.uk).
Ru(1)–Co(1)
Ru(1)–C(4)
Co(1)–C(2)
Co(1)–C(4)
C(2)–C(3)
2.627(1)
2.049(7)
2.084(7)
2.045(7)
1.40(1)
Ru(1)–C(1)
Co(1)–C(1)
Co(1)–C(3)
C(1)–C(2)
C(3)–C(4)
2.101(7)
2.023(7)
2.124(7)
1.438(9)
1.421(9)
Bond angles
Co(1)–Ru(1)–C(1)
C(1)–Ru(1)–C(4)
Ru(1)–Co(1)–C(2)
Ru(1)–Co(1)–C(4)
C(1)–Co(1)–C(3)
C(2)–Co(1)–C(3)
C(3)–Co(1)–C(4)
Ru(1)–C(1)–C(2)
Co(1)–C(2)–C(1)
C(1)–C(2)–C(3)
Co(1)–C(3)–C(4)
Ru(1)–C(4)–Co(1)
Co(1)–C(4)–C(3)
49.1(2)
76.7(3)
77.5(2)
50.1(2)
70.8(3)
38.8(3)
39.8(3)
113.3(5)
67.2(4)
116.0(7)
67.1(4)
79.8(3)
73.1(4)
Co(1)–Ru(1)–C(4)
Ru(1)–Co(1)–C(1)
Ru(1)–Co(1)–C(3)
C(1)–Co(1)–C(2)
C(1)–Co(1)–C(4)
C(2)–Co(1)–C(4)
Ru(1)–C(1)–Co(1)
Co(1)–C(1)–C(2)
Co(1)–C(2)–C(3)
Co(1)–C(3)–C(2)
C(2)–C(3)–C(4)
50.0(2)
51.8(2)
77.0(2)
41.0(3)
78.6(3)
69.2(3)
79.1(3)
71.8(4)
72.2(4)
69.1(4)
112.7(6)
117.3(5)
Acknowledgements
We thank Professor Haruo Matsuyama of TMU for
measuring mass spectra. This work was supported by a
Grant–in–Aid for Scientific Research (No. 10640549,
Priority Areas No. 284-11120246 and 401-10149104)
from The Ministry of Education, Science, Sports and
Culture, Japan.
Ru(1)–C(4)–C(3)
a Estimated S.D.s in the least significant figure are given in paren-
theses.

H. Matsuzaka et al. / Journal of Organometallic Chemistry 596 (2000) 121–129
129
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