Structures and reactivities of diruthenium dithiolene complexes and triruthenium sulfido clusters derived from a hydrosulfido-bridged diruthenium complex

Article abstract of DOI:10.1021/om980214d

The hydrosulfido-bridged diruthenium complex [Cp*RuCl(μ₂-SH)₂RuClCp*] (1) reacted with an excess of triethylamine to give the cubane-type tetraruthenium sulfido cluster [(Cp*Ru)₄-(μ₃-S)₄] (3) When the reaction was carried out in the presence of alkynes, the dithiolene-bridged diruthenium complexes [(Cp*Ru)₂(μ₂-η₂:η ⁴-S₂C₂RR′)] (4) were obtained The dithiolene ring in 4 is almost planar. Treatment of 4 with CO afforded the carbonyl complexes [Cp*Ru(CO)(μ₂-η²:η⁴-S ₂C₂RR′)RuCp*] (5) containing a bent dithiolene ring. On the other hand the reaction of 1 with an equimolar amount of [RuH₂(PPh₃)₄] resulted in the formation of the triruthenium sulfido cluster [(Cp*Ru)₂(μ₃-S)₂(μ ₂-H)RuCl(PPh₃)₂] (6). Cluster 6 reacted with an excess of NaBH₄ in ethanol to give the dihydrido cluster [(Cp*Ru)2(μ3-S)2μ2-H)-RuH(PPh₃)₂] (7), which was further converted to the dicarbonyl cluster [(Cp*Ru)₂(μ₃-S)₂Ru-(CO) ₂(PPh₃)] (8) under CO. The detailed structures for [(Cp*Ru)₂(μ2-η²:η⁴-S ₂C₂HBu^t)] (4a), [Cp*Ru(CO)(μ₂-η²:η⁴-S ₂C₂HBu^t)RuCp*] (5a), and 6-8 have been determined by X-ray crystallography.

Full text of DOI:10.1021/om980214d

Organometallics 1998, 17, 3429-3436
3429
Str u ctu r es a n d Rea ctivities of Dir u th en iu m Dith iolen e
Com p lexes a n d Tr ir u th en iu m Su lfid o Clu ster s Der ived
fr om a Hyd r osu lfid o-Br id ged Dir u th en iu m Com p lex
Shigeki Kuwata, Masahiro Andou, Kohjiro Hashizume, Yasushi Mizobe,† and
Masanobu Hidai*
Department of Chemistry and Biotechnology, Graduate School of Engineering, The University
of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, J apan
Received March 23, 1998
The hydrosulfido-bridged diruthenium complex [Cp*RuCl(µ2-SH)2RuClCp*] (1) reacted with
an excess of triethylamine to give the cubane-type tetraruthenium sulfido cluster [(Cp*Ru)4-
(µ3-S)4] (3). When the reaction was carried out in the presence of alkynes, the dithiolene-
bridged diruthenium complexes [(Cp*Ru)2(µ2-η2:η4-S2C2RR′)] (4) were obtained. The dithi-
olene ring in 4 is almost planar. Treatment of 4 with CO afforded the carbonyl complexes
[Cp*Ru(CO)(µ2-η2:η4-S2C2RR′)RuCp*] (5) containing a bent dithiolene ring. On the other
hand, the reaction of 1 with an equimolar amount of [RuH2(PPh3)4] resulted in the formation
of the triruthenium sulfido cluster [(Cp*Ru)2(µ3-S)2(µ2-H)RuCl(PPh3)2] (6). Cluster 6 reacted
with an excess of NaBH4 in ethanol to give the dihydrido cluster [(Cp*Ru)2(µ3-S)2(µ2-H)-
RuH(PPh3)2] (7), which was further converted to the dicarbonyl cluster [(Cp*Ru)2(µ3-S)2Ru-
(CO)2(PPh3)] (8) under CO. The detailed structures for [(Cp*Ru)2(µ2-η2:η4-S2C2HBut)] (4a ),
[Cp*Ru(CO)(µ2-η2:η4-S2C2HBut)RuCp*] (5a ), and 6-8 have been determined by X-ray
crystallography.
Sch em e 1
In tr od u ction
R-Elimination of hydrogen halides or alkanes has
been recognized as a valuable route to prepare species
with metal-ligand multiple bonds.1,2 These species
often dimerize or are trapped with dative ligands or
unsaturated organic molecules (Scheme 1). This type
of elimination in dinuclear complexes would result in
the formation of a heteroatom-bridged coordinatively
unsaturated dinuclear center. However, only a few oxo-
and phosphinidene-bridged species have been prepared
by this method in the case of dinuclear complexes3 apart
from simple deprotonation of bridging hydroxo and
phosphido ligands.4 The corresponding reactions for
hydrosulfido-bridged dinuclear complexes have also
been poorly exploited,5 although they are expected to
lead to the rational construction of sulfido-bridged
coordinatively unsaturated dinuclear centers, which
have some relevance to the FeMo-cofactor in nitroge-
nase6 and nonmolecular metal sulfide catalysts.7
† Present address: Institute of Industrial Science, The University
of Tokyo, Roppongi, Minato-ku, Tokyo 106-8558, J apan.
(1) Nugent, W. A.; Mayer, J . M. Metal-Ligand Multiple Bonds;
Wiley-Interscience: New York, 1988.
As an extension of our studies on the preparation and
reactivities of thiolato-bridged diruthenium,8 dirhodium,
and diiridium complexes,9 we have recently demon-
strated that the hydrosulfido-bridged dinuclear com-
plexes [Cp*MCl(µ2-SH)2MClCp*] (1, M ) Ru;10 2a , M
) Ir; 2b, M ) Rh11) serve as a versatile precursor to
(2) For oxo complexes, see: (a) Carney, M. J .; Walsh, P. J .;
Hollander, F. J .; Bergman, R. G. Organometallics 1992, 11, 761. For
imido and hydrazido(2-) complexes, see: (b) Glueck, D. S.; Wu, J .;
Hollander, F. J .; Bergman, R. G. J . Am. Chem. Soc. 1991, 113, 2041.
(c) Walsh, P. J .; Hollander, F. J .; Bergman, R. G. Organometallics 1993,
12, 3705. (d) Schrock, R. R.; Liu, A. H.; O’Regan, M. B.; Finch, W. C.;
Payack, J . F. Inorg. Chem. 1988, 27, 3574. (e) Walsh, P. J .; Carney,
M. J .; Bergman, R. G. J . Am. Chem. Soc. 1991, 113, 6343. For sulfido
complexes, see ref 2a and (f) Dobbs, D. A.; Bergman, R. G. Inorg. Chem.
1994, 33, 5329. (g) Liang, H.-C.; Shapley, P. A. Organometallics 1996,
15, 1331.
(3) McGhee, W. D.; Foo, T.; Hollander, F. J .; Bergman, R. G. J . Am.
Chem. Soc. 1988, 110, 8543.
(4) (a) Li, J .-J .; Li, W.; Sharp, P. R. Inorg. Chem. 1996, 35, 604. (b)
Kourkine, I. V.; Glueck, D. S. Inorg. Chem. 1997, 36, 5160.
(5) Ruffing, C. J .; Rauchfuss, T. B. Organometallics 1985, 4, 524.
(6) (a) Howard, J . B.; Rees, D. C. Chem. Rev. 1996, 96, 2965. (b)
Burgess, B. K.; Lowe, D. J . Chem. Rev. 1996, 96, 2983. (c) Sellmann,
D.; Sutter, J . Acc. Chem. Res. 1997, 30, 460.
(7) (a) Rakowski DuBois, M. Chem. Rev. 1989, 89, 1. (b) Sa´nchez-
Delgado, R. A. J . Mol. Catal. 1994, 86, 287. (c) Startsev, A. N. Catal.
Rev.sSci. Eng. 1995, 37, 353. (d) Bianchini, C.; Meli, A. J . Chem. Soc.,
Dalton Trans. 1996, 801.
S0276-7333(98)00214-3 CCC: $15.00 © 1998 American Chemical Society
Publication on Web 07/03/1998

3430 Organometallics, Vol. 17, No. 16, 1998
Kuwata et al.
Sch em e 2
the tri- and tetranuclear sulfido clusters containing the
Cp*M(µ-S)2MCp* fragment. Generation of intermediary
[Cp*Ir(µ2-S)2IrCp*] from 2a with the aid of triethyl-
1
amine has been substantiated from the H NMR study,
which finally gives rise to the formation of the cubane-
type cluster [(Cp*Ir)4(µ3-S)4]. We have now investigated
in detail the reactivity of such sulfido-bridged dinuclear
species obtained through dehydrohalogenation of the
hydrosulfido-bridged dinuclear complexes. In this pa-
per, we describe the trapping of the intermediate
[Cp*Ru(µ2-S)2RuCp*] with alkynes, which results in the
formation of the dithiolene-bridged diruthenium com-
plexes [(Cp*Ru)2(µ2-η2:η4-S2C2R2)] (4). Utilization of 1
as a building block for synthesis of the tri- and tetraru-
thenium sulfido clusters [(Cp*Ru)4(µ3-S)4] (3) and
[(Cp*Ru)2(µ3-S)2(µ2-H)RuCl(PPh3)2] (6) is also reported.
Resu lts a n d Discu ssion
F or m a tion of a Cu ba n e-Typ e Tetr a r u th en iu m
Su lfido Clu ster fr om a Hydr osu lfido-Br idged Dir u -
t h en iu m Com p lex. We have already demonstrated
that the thermolysis of the hydrosulfido-bridged diru-
thenium complex 1 results in the formation of the
dicationic cubane-type cluster [(Cp*Ru)4(µ3-S)4]Cl2,10
whereas treatment of the corresponding iridium and
rhodium complexes 2 with triethylamine at room tem-
perature affords the neutral cubane-type clusters
[(Cp*M)4(µ3-S)4] (M ) Ir, Rh).11 To clarify the difference
between 1 and 2 in the formation of these cubane-type
clusters, we have investigated these reactions in more
detail.
that the platinum analogue [Pt(PPh3)2(µ2-S)2Pt(PPh3)2]12
and the oxo-bridged complex [Cp*Ir(µ2-O)2IrCp*]3 are
isolable and do not dimerize, although the former
readily reacts with a variety of transition-metal com-
plexes to afford homo- and heterometallic sulfido ag-
gregates.12 As an another related reaction, the hydroxo-
bridged diplatinum complex [Pt(PMe2Ph)2(µ2-OH)2Pt-
(PMe2Ph)2][BF4]2 is known to be deprotonated with
base, giving the corresponding oxo-bridged complex [Pt-
(PMe2Ph)2(µ2-O)2Pt(PMe2Ph)2], which is unstable in
solution and converted to the triplatinum oxo cluster
[{Pt(PMe2Ph)2}3(µ3-O)2][BF4]2.4a We note that cluster
3 has already been prepared by treatment of [(Cp*Ru)4-
(µ3-Cl)4] with NaSH, although it requires more forcing
conditions and is accompanied by intermittent contami-
nation of [Cp*4Ru4S5].13
Like its iridium and rhodium analogues 2, complex 1
cleanly reacted with an excess of triethylamine to afford
the neutral cubane-type cluster [(Cp*Ru)4(µ3-S)4] (3) in
moderate yield (eq 1). In contrast to the iridium
On the other hand, when a solution of the iridium and
rhodium complexes 2 in toluene was heated under
reflux, only dehydrohalogenation occurred to give the
neutral cubane-type clusters [(Cp*M)4(µ3-S)4] (M ) Ir,
Rh); H2 gas was not detected in the reaction mixture
(Scheme 2). This contrasts the formation of the dica-
tionic cluster [(Cp*Ru)4(µ3-S)4]Cl2 from 1 under similar
conditions.10 The thermolysis product from the hydro-
sulfido complexes seems to depend on the ease of
oxidation of the neutral clusters [(Cp*M)4(µ3-S)4] (M )
Ru, Ir, Rh). Studies on chemical and electrochemical
oxidation of these clusters clearly support this idea. The
E1/2 values for oxidation (Ru -0.71 and -0.28 V; Ir
-0.46 and -0.19 V; Rh -0.33 and +0.29 V vs SCE) show
that the ruthenium cluster 3 is more easily oxidized
than the corresponding iridium and rhodium clusters
[(Cp*M)4(µ3-S)4] (M ) Ir, Rh). Actually, the neutral
ruthenium cluster 3 immediately reacted with an excess
of hydrogen chloride, even at room temperature, giving
the dicationic cluster [(Cp*Ru)4(µ3-S)4]Cl2 in good yield.
Thus, the formation of the cationic cluster [(Cp*Ru)4-
(µ3-S)4]Cl2 from 1 can be explained by the oxidation of
3 with hydrogen chloride, which is concomitantly gener-
ated with 3 from 1.
complex 2a , however, the intermediary [Cp*Ru(µ2-S)2-
RuCp*] could not be detected by 1H NMR since the
reaction proceeded so fast, similar to that of the rhodium
complex 2b. Facile dimerization suggests a high reac-
tivity of these sulfido-bridged species. It is of interest
(8) (a) Hidai, M.; Mizobe, Y.; Matsuzaka, H. J . Organomet. Chem.
1994, 473, 1. (b) Hidai, M.; Mizobe, Y. In Transition Metal Sulfur
Chemistry; Stiefel, E. I., Matsumoto, K., Eds.; American Chemical
Society: Washington, DC, 1996; p 310. (c) Takagi, Y.; Matsuzaka, H.;
Ishii, Y.; Hidai, M. Organometallics 1997, 16, 4445. (d) Nishibayashi,
Y.; Yamanashi, M.; Takagi, Y.; Hidai, M. Chem. Commun. 1997, 859.
(9) (a) Nishio, M.; Matsuzaka, H.; Mizobe, Y.; Hidai, M. Angew.
Chem., Int. Ed. Engl. 1996, 35, 872. (b) Nishio, M.; Matsuzaka, H.;
Mizobe, Y.; Hidai, M. Inorg. Chim. Acta 1997, 263, 119. (c) Nishio, M.;
Mizobe, Y.; Matsuzaka, H.; Hidai, M. Inorg. Chim. Acta 1997, 265,
59.
(10) Hashizume, K.; Mizobe, Y.; Hidai, M. Organometallics 1996,
15, 3303.
(11) (a) Tang, Z.; Nomura, Y.; Ishii, Y.; Mizobe, Y.; Hidai, M.
Organometallics 1997, 16, 151. (b) Tang, Z.; Nomura, Y.; Ishii, Y.;
Mizobe, Y.; Hidai, M. Inorg. Chim. Acta 1998, 267, 73.
(12) Liu, H.; Tan, A. L.; Mok, K. F.; Mak, T. C. W.; Batsanov, A. S.;
Howard, J . A. K.; Hor, T. S. A. J . Am. Chem. Soc. 1997, 119, 11006
and references therein.
(13) Houser, E. J .; Dev, S.; Ogilvy, A. E.; Rauchfuss, T. B.; Wilson,
S. R. Organometallics 1993, 12, 4678.

Dithiolene- and Sulfido-Bridged Ru Complexes
Organometallics, Vol. 17, No. 16, 1998 3431
Tr a p p in g of [Cp *Ru (µ2-S)2Ru Cp *] w ith Alk yn es.
F or m a t ion of Dit h iolen e-Br id ged Dir u t h en iu m
Com p lexes. Formation of the cubane-type cluster 3
from 1 described above suggests that the coordinatively
unsaturated intermediate [Cp*Ru(µ2-S)2RuCp*] is gen-
erated upon thermolysis of 1 or treatment of 1 with
base. As to a related reaction, Rauchfuss and co-
workers have demonstrated that the reactions of [(CpEt-
Ru)2(µ2-η1:η1-S2)(µ2-η2:η2-S2)] (CpEt ) η5-C5Me4Et) with
2 equiv of PBu3 in the presence of CO or diphenylacety-
15
lene afford [CpEtRu(CO)(µ2-S)2Ru(CO)CpEt
]
or [(CpEt
-
Ru)2(µ2-η2:η4-S2C2Ph2)],16 respectively. Although the
formation of intermediary [CpEtRu(µ2-S)2RuCpEt] was
not mentioned, these reactions seem to involve such a
sulfido-bridged species and stimulated us to investigate
the trapping of [Cp*Ru(µ2-S)2RuCp*] generated from the
hydrosulfido complex 1 with unsaturated organic mol-
ecules. As expected, dehydrohalogenation of 1 in the
presence of an excess of alkynes afforded the dithiolene-
bridged diruthenium complexes [(Cp*Ru)2(µ2-η2:η4-S2C2-
RR′)] (4; eq 2). Although the isolated yield of 4 was
F igu r e 1. Molecular structure of 4a with atom-numbering
scheme.
Ta ble 1. Selected In ter a tom ic Dista n ces (Å) for 4a
a n d 5a
4a
5a
Ru(1)-Ru(2)
Ru(1)-S(1)
Ru(1)-S(2)
Ru(2)-S(1)
Ru(2)-S(2)
Ru(2)-C(21)
Ru(2)-C(22)
S(1)-C(21)
S(2)-C(22)
C(21)-C(22)
2.993(2)
2.271(2)
2.262(2)
2.437(2)
2.428(2)
2.165(6)
2.204(6)
1.738(6)
1.772(5)
1.399(7)
3.6547(6)
2.3785(9)
2.394(1)
2.407(1)
2.4273(9)
2.135(3)
2.176(3)
1.746(4)
1.773(3)
1.398(4)
reactive complexes.18 As to alkylacetylenes, only 2-bu-
-
tyne is known to react with ReS4 and S8 to give the
bis(dithiolene) complex [ReS(S2C2Me2)2]-.20 Interest-
ingly, complex 1 readily reacted with a variety of
alkynes including 3,3-dimethyl-1-butyne and acetylene
to form dithiolene complexes in the presence of triethyl-
amine under very ambient conditions. This suggests a
high reactivity of the sulfido-bridged species [Cp*Ru-
(µ2-S)2RuCp*]. On the other hand, the parent 1 itself
did not react with these unactivated alkynes at room
temperature, although a highly activated alkyne, di-
methyl acetylenedicarboxylate, did react with 1 in the
absence of triethylamine to give the dithiolene-bridged
complex 4c in low yield. It is to be noted that the
preparation of the CpEt analogue [(CpEtRu)2(µ2-η2:η4-
S2C2Ph2)] reported by Rauchfuss et al. requires more
forcing conditions (70 °C) compared with that described
here.
moderate because of the high solubility of 4 in common
organic solvents, the reactions proceeded cleanly for
1
4a -d by H NMR. On the other hand, diphenylacety-
lene was less reactive and a large amount of the cubane-
type cluster 3 was isolated along with the dithiolene
complex 4e from the reaction mixture. The 1H NMR
spectra of 4 exhibit two inequivalent singlets due to the
Cp* methyl protons with the same intensity. The
signals for the hydrogen atoms attached to the dithi-
olene ring also appear at 5-6 ppm for 4a , 4b, and 4d .
In the 13C{1H} NMR spectra, the signals ascribed to the
ring carbon atoms in the dithiolene ligands are observed
in the range of 85-125 ppm, which is considerably
higher field than those for other dithiolene complexes
(130-180 ppm).17
Trapping of [Cp*Ru(µ2-S)2RuCp*] with other unsatur-
ated organic molecules such as alkenes and nitriles was
also attempted; however, this resulted in the formation
of only the cubane-type cluster 3. Analogous dehydro-
halogenation of the iridium and rhodium complexes 2
with triethylamine in the presence of p-tolylacetylene
also afforded the cubane-type clusters [(Cp*M)4(µ3-S)4]
(M ) Ir, Rh) exclusively.
Addition of alkynes to metal sulfido complexes has
been established as a synthetic method for dithiolene
complexes.18,19 However, the alkynes employed are
usually limited to those activated by electron-withdraw-
ing substituents. Preparation of dithiolene complexes
from acetylene or alkynes with electron-donating alkyl
substituents are only achieved by using a few highly
An X-ray analysis of [(Cp*Ru)2(µ2-η2:η4-S2C2HBut)]
(4a ) has disclosed the dithiolene-bridged dinuclear
structure of 4. The molecular structure is shown in
Figure 1, whereas selected bond distances and angles
are listed in Table 1. The structure of 4a closely
resembles that of [(CpEtRu)2(µ2-η2:η4-S2C2Ph2)]16 and the
(14) Venturelli, A.; Rauchfuss, T. B. J . Am. Chem. Soc. 1994, 116,
4824.
(15) Ogilvy, A. E.; Rauchfuss, T. B. Organometallics 1988, 7, 1884.
(16) Rauchfuss, T. B.; Rodgers, D. P. S.; Wilson, S. R. J . Am. Chem.
Soc. 1986, 108, 3114.
(17) Inomata, S.; Takano, H.; Hiyama, K.; Tobita, H.; Ogino, H.
Organometallics 1995, 14, 2112.
(18) Rakowski DuBois, M.; J agirdar, B. R.; Dietz, S.; Noll, B. C.
Organometallics 1997, 16, 294 and references therein.
(19) Kawaguchi, H.; Yamada, K.; Lang, J .-P.; Tatsumi, K. J . Am.
Chem. Soc. 1997, 119, 10346.
(20) Goodman, J . T.; Inomata, S.; Rauchfuss, T. B. J . Am. Chem.
Soc. 1996, 118, 11674.

3432 Organometallics, Vol. 17, No. 16, 1998
Kuwata et al.
isoelectronic dimanganese complex [{Mn(CO)3}2(µ2-η2:
η4-S2C2Ph2)].21 The dithiolene ligand bridges the two
ruthenium atoms unsymmetrically: it binds to the Ru-
(1) atom through only two sulfur atoms whereas it binds
to the Ru(2) atom through all four atoms in the
dithiolene ligand. The distances of Ru(1)-S (2.262(2)
and 2.271(2) Å) are shorter than those of Ru(2)-S
(2.428(2) and 2.437(2) Å). A similar unsymmetrical
bridging has been deduced for the related diruthenium
benzenedithiolato complex [Cp*Ru(µ2-S2C6H4)RuCp*]
1
from its H NMR spectrum.22 The Ru-Ru distance of
2.993(2) Å is significantly longer than those observed
in thiolato-bridged diruthenium complexes with a Ru-
Ru single bond (2.6-2.9 Å)8 but still indicates a Ru-
Ru interaction. This is congruent with the effective
atomic number (EAN) rule if the bridging dithiolene
ligand is regarded as a neutral eight-electron donor. The
dithiolene ring in 4a is almost completely planar, as in
the isoelectronic complexes mentioned above: the di-
hedral angle between the plane of S(1)-Ru(1)-S(2) and
the least-squares plane of S(1)-C(21)-C(22)-S(2) is
7.9°.
P r ep a r a tion a n d Str u ctu r e of [Cp *Ru (CO)(µ2-η2:
η4-S2C2RR′)Ru Cp *] (5). When solutions of the dithi-
olene-bridged diruthenium complexes 4 were stirred
under a CO atmosphere, the carbonyl complexes [Cp*Ru-
(CO)(µ2-η2:η4-S2C2RR′)RuCp*] (5) were obtained in good
yield (eq 3). A strong band ascribed to the terminally
F igu r e 2. Molecular structure of 5a with atom-numbering
scheme.
Ru(1)-S and Ru(2)-S become essentially equal. These
features are common with [Cp*Fe(CO){µ2-η2:η4-S2C2-
(COOMe)2}FeCp*], whose dithiolene and CO ligands
are, however, mutually trans-orientated. The dihedral
angle between the two Ru2S planes in 5a (143.44°) is
significantly larger than that in 4a (116.03°). It is of
interest that the dithiolato complex [(Cp*Ru)2(µ2-η2:η4-
S2C6H4)] is also known to react with CO or P(OMe)3 to
give the closely related diruthenium complexes [Cp*RuL-
(µ2-η2:η4-S2C6H4)RuCp*] (L ) CO, P(OMe)3), the latter
of which has a similar cis orientation of the dithiolato
and phosphite ligands that has been confirmed by X-ray
crystallography.22
P r ep a r a tion a n d Str u ctu r e of [(Cp *Ru )2(µ3-S)2-
(µ2-H)Ru Cl(P P h 3)2] (6). We have previously found
that the hydrosulfido-bridged diruthenium complex 1
reacts with [RhCl(PPh3)3] to give the heterometallic
sulfido cluster [(µ2-H)(Cp*Ru)2(µ3-S)2RhCl2(PPh3)].10 Simi-
larly, the reaction of 1 with a nearly equimolar amount
of [RuH2(PPh3)4] resulted in the formation of the sulfido-
capped triruthenium cluster [(Cp*Ru)2(µ3-S)2(µ2-H)Ru-
Cl(PPh3)2] (6) in moderate yield (eq 4). Concomitant
bound carbonyl ligand is observed around 1900 cm-1 in
1
the IR spectra of 5. The H and 13C{1H} spectra clearly
demonstrate the presence of the dithiolene ligand: the
resonances for the hydrogen atoms attached to the
dithiolene ring appear at 5-7 ppm and those for the
ring carbon atoms in the dithiolene ligands in the range
of 80-125 ppm. It is worth mentioning that the iron
analogue of 5, [Cp*Fe(CO){µ2-η2:η4-S2C2(COOMe)2}-
FeCp*], has been isolated in low yield from the reaction
of [Cp*2Fe2(CO)4] with elemental sulfur and dimethyl
acetylenedicarboxylate.17
An X-ray analysis of [Cp*Ru(CO)(µ2-η2:η4-S2C2HBut)-
RuCp*] (5a ) has been undertaken to compare the
structures of both 4 and 5 in detail (Figure 2). In
contrast to 4a , the Ru(1)-Ru(2) distance of 3.6547(6) Å
precludes any metal-metal bonding. Coordination of
CO also affected the bridging manner of the dithiolene
ligand. Although the ligand still bridges the two
ruthenium atoms in an η2:η4-coordination mode, the
dithiolene ring in 5a is now folded with a dihedral angle
of 40.9° along the S(1)-S(2) vector and the distances of
evolution of H2 has been confirmed by GLC analysis.
The 1H NMR spectrum of 6 exhibits a high-field hydrido
resonance split by two equivalent phosphorus nuclei as
well as two inequivalent singlets ascribed to the Cp*
methyl protons. The 31P{1H} NMR spectrum also
demonstrates the equivalence of the two phosphine
ligands. On the other hand, no band ascribed to νRuH
is observed in the IR spectrum. These spectroscopic
data suggest that the hydrido ligand bridges the two
ruthenium atoms, one originating from 1 and the other
from incorporated ruthenium atom. In contrast, the
hydrido ligand in [(µ2-H)(Cp*Ru)2(µ3-S)2RhCl2(PPh3)]
bridges two ruthenium atoms and shows no coupling
with rhodium and phosphorus nuclei in the 1H NMR
spectrum.10 It is also worth mentioning that when
[RuH2(PPh3)4] is treated with the hydrosulfido-bridged
diiridium complex 2a in place of 1, the triangular cluster
[(Cp*Ir)2(µ3-S)2RuCl2(PPh3)] with no hydrido ligand is
obtained.23
(21) Lindner, E.; Butz, I. P.; Hoehne, S.; Hiller, W.; Fawzi, R. J .
Organomet. Chem. 1983, 259, 99.
(22) Ho¨rnig, A.; Englert, U.; Ko¨lle, U. J . Organomet. Chem. 1994,
464, C25.

Dithiolene- and Sulfido-Bridged Ru Complexes
Organometallics, Vol. 17, No. 16, 1998 3433
Sch em e 3
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles
rule, there are three Ru-Ru single bonds in 6, whose
distances at 2.778(1)-2.868(1) Å are comparable to
those in an isoelectronic Ru(II)/Ru(III)/Ru(III) cluster
[(Cp*Ru)3(µ3-S)2(µ2-H)] (2.798(2)-2.851(3) Å)24 and
slightly shorter than those in Ru(II)/Ru(II)/Ru(II) clus-
ters [(Cp*Ru)3(µ3-S)(µ3-X)] (X ) Cl, SPri; 2.874(2)-
2.9599(9) Å).24 The two µ3-S ligands are located closer
to the Ru(1) and Ru(2) atoms than to the Ru(3) atom:
the distances from these S atoms to the former ruthe-
nium atoms (2.233(3)-2.300(3) Å) are slightly shorter
than those to the latter (2.372(3) and 2.376(2) Å).
Thus, the present study has again shown that the
hydrosulfido-bridged dinuclear complex 1 as well as its
iridium and rhodium analogues 2 can serve as a good
precursor to the clusters with higher nuclearity. It
should be emphasized that the triruthenium cluster 6
prepared through this synthetic pathway has different
types of terminal ligands, in contrast to the clusters with
Ru3(µ3-S)2 cores reported so far, including [(Cp*Ru)3(µ3-
S)2(µ2-H)]24 and [(p-cymene)3Ru3(µ3-S)2]n+ (n ) 0, 2).25
P r ep a r a tion a n d Str u ctu r e of [(Cp *Ru )2(µ3-S)2-
(µ2-H)Ru H(P P h 3)2] (7). Cluster 6 has labile Cl and
PPh3 ligands along with tightly bound Cp* ligands.
Thus site-specific substitution is expected to occur in 6.
Indeed, when the mixture of 6 and an excess of NaBH4
in ethanol was heated at 50 °C, the dihydrido cluster
[(Cp*Ru)2(µ3-S)2(µ2-H)RuH(PPh3)2] (7) was obtained in
high yield (Scheme 3). Contrary to the solid-state
structure (vide infra), the 1H NMR spectrum of 7
exhibits one sharp singlet due to the Cp* methyl
protons, even at -50 °C, indicating the fluxional be-
havior of the terminal and bridging hydrido ligands in
solution. The spectrum also shows only one high-field
hydrido resonance with the intensity of 2 H, which is
split into a triplet by two equivalent phosphorus nuclei;
the equivalence of two phosphine ligands is further
supported by the 31P{1H} NMR spectrum. The IR
(d eg) for 6-8
6‚0.5THF
7‚THF
8
Distances
2.842(1)
2.868(1)
2.778(1)
2.233(3)
2.235(3)
2.287(3)
2.300(3)
2.372(3)
2.376(2)
2.391(3)
2.424(3)
1.67
Ru(1)-Ru(2)
Ru(1)-Ru(3)
Ru(2)-Ru(3)
Ru(1)-S(1)
Ru(1)-S(2)
Ru(2)-S(1)
Ru(2)-S(2)
Ru(3)-S(1)
Ru(3)-S(2)
Ru(3)-P(1)
Ru(3)-P(2)
2.811(3)
2.818(2)
2.814(2)
2.241(1)
2.233(1)
2.291(1)
2.309(1)
2.360(1)
2.390(1)
2.325(1)
2.303(1)
1.67(4)
2.858(1)
2.841(1)
2.827(2)
2.243(3)
2.271(3)
2.274(3)
2.275(3)
2.378(3)
2.400(3)
2.313(4)
a
Ru(3)-Hb
a
Ru(2)-Hb
1.48
1.74(4)
1.52(4)
Ru(3)-H(69)
Angles
58.21(3)
61.35(3)
60.44(3)
Ru(2)-Ru(1)-Ru(3)
Ru(1)-Ru(2)-Ru(3)
Ru(1)-Ru(3)-Ru(2)
58.91(2)
59.66(1)
61.43(2)
59.46(3)
59.97(3)
60.56(4)
a
Hb ) H(61) (6‚0.5THF) or H(70) (7‚THF).
spectrum shows a characteristic band at 1919 cm-1
,
which is assignable to stretching of the Ru-H bond.
An X-ray analysis has been carried out to clarify the
detailed structure of 7; an ORTEP drawing of 7 is
depicted in Figure 4, and selected bond distances and
angles are listed in Table 2. Cluster 7 has essentially
the same (Cp*Ru)2(µ3-S)2Ru core as 6. The two hydrido
ligands have been found in the final Fourier map; one
of them (H(69)) is bound to Ru(3) as a terminal ligand,
whereas the other (H(70)) bridges the Ru(2) and Ru(3)
atoms. Replacement of the chloro ligand in 6 with a
sterically less demanding hydrido ligand has changed
the coordination geometry around the Ru(3) atom
slightly: the P(2) atom, which is on the opposite side of
F igu r e 3. Molecular structure of 6‚0.5THF with atom-
numbering scheme. Solvating THF is omitted for clarity.
The trinuclear structure of 6 has unequivocally been
established by X-ray crystallography; an ORTEP draw-
ing is shown in Figure 3, and selected bond distances
and angles are listed in Table 2. Cluster 6 has a
triangular Ru3 core capped by two µ3-S ligands from
both sides. The hydrido ligand, which has been found
in the final difference Fourier map, bridges the Ru(2)
and Ru(3) atoms. Neglecting the Ru-Ru interactions,
the coordination geometry around the Ru(3) atom is
distorted octahedral with the H and Cl ligands in
mutually trans positions. As expected from the EAN
(24) Hashizume, K.; Mizobe, Y.; Hidai, M. Organometallics 1995,
14, 5367.
(25) Lockemeyer, J . R.; Rauchfuss, T. B.; Rheingold, A. L. J . Am.
Chem. Soc. 1989, 111, 5733.
(23) Tang, Z.; Ishii, Y.; Mizobe, Y.; Hidai, M. Unpublished results.

3434 Organometallics, Vol. 17, No. 16, 1998
Kuwata et al.
F igu r e 5. Molecular structure of 8 with atom-numbering
scheme. Only one of the disordered components is shown
for the phenyl rings.
F igu r e 4. Molecular structure of 7‚THF with atom-
numbering scheme. Solvating THF is omitted for clarity.
the chloro ligand as to the Ru(3)-S(1)-S(2) plane in 6
(1.04 Å apart from the plane), has come to the same
side of the terminal hydrido ligand (0.17 Å apart from
the plane).
not only the dithiolene-bridged diruthenium complexes
4 but also the tri- and tetraruthenium sulfido clusters
6 and 3, all of which contain the Cp*Ru(µ-S)2RuCp*
fragment. These reactivities of 1 strongly suggest the
formation of the coordinatively unsaturated sulfido-
bridged intermediate [Cp*Ru(µ2-S)2RuCp*] upon treat-
ment of 1 with base. Formation of such an intermediate
is common with the corresponding diiridium and dirhod-
ium complexes 2. It may be considered that R-dehy-
drohalogenation of hydrosulfido-bridged dinuclear com-
plexes with base provides a general method to afford
coordinatively unsaturated sulfido-bridged dinuclear
centers. These intermediary species readily dimerize
in the absence of substrates to give the cubane-type
clusters [(Cp*M)4(µ3-S)4] (M ) Ru, Ir, Rh). In the
presence of alkynes, the intermediary species [Cp*Ru-
(µ2-S)2RuCp*] is transformed into the dithiolene-bridged
diruthenium complexes 4, which further reacts with CO
to give the carbonyl complexes 5. The triruthenium
sulfido cluster 6 with a chloride anion and a bridging
hydrido ligand undergoes site-specific ligand substitu-
tion to give the dihydrido cluster 7, which has further
been converted to the dicarbonyl cluster 8 under CO;
the (Cp*Ru)2(µ3-S)2Ru core is retained throughout these
reactions.
P r epar ation an d Str u ctu r e of [(Cp*Ru )2(µ3-S)2Ru -
(CO)2(P P h 3)] (8). Reaction of 7 with CO (1 atm) at 50
°C resulted in the formation of the Ru(II)/Ru(II)/Ru(II)
dicarbonyl cluster [(Cp*Ru)2(µ3-S)2Ru(CO)2(PPh3)] (8) in
35% yield (Scheme 3). The 1H NMR spectrum of 8
shows the presence of Cp* and PPh3 ligands in a ratio
of 2:1 and the absence of hydrido ligands. Two strong
bands at 1970 and 1921 cm-1 ascribed to νCO are
observed in the IR spectrum; the wavenumbers are
slightly lower than those of the Ru(II) complex cct-
[RuCl2(CO)2(PPh3)2] (2050 and 1990 cm-1),26 suggesting
that the (Cp*Ru)2(µ3-S)2Ru fragment in 8 is more
electron donating than the RuCl2(PPh3) one. It may be
noted that the reaction of [RuH2(PPh3)4]27a or [RuH2-
(N2)(PPh3)3]27b with CO gives only [RuH2(CO)(PPh3)3],
and replacement of H2 with CO does not occur, at least,
at room temperature. The isoelectronic clusters
[(Cp*Fe)2(µ3-S)2M(CO)3] (M ) Fe, Ru) have been pre-
pared from the reaction of [(Cp*Fe)2(µ2-η1:η1-S2)(µ2-η2:
η2-S2)] with the corresponding metal carbonyl com-
plexes.28
The molecular structure of 8 determined by X-ray
analysis is depicted in Figure 5, and selected bond
distances and angles are listed in Table 2, which clearly
shows that the (Cp*Ru)2(µ3-S)2Ru core in 6 and 7 has
been retained in 8. However, the coordination geometry
around the Ru(3) atom is now trigonal bipyramidal with
the S(2) and P atoms at the two apical positions. The
three Ru(II)-Ru(II) single bond distances at 2.827(2)-
2.858(1) Å are still comparable to the Ru-Ru distances
in Ru(III)/Ru(III)/Ru(II) clusters 6, 7, and [(Cp*Ru)3(µ3-
S)2(µ2-H)] (2.778(1)-2.868(1) Å) rather than those in Ru-
(II)/Ru(II)/Ru(II) clusters (vide supra).
Exp er im en ta l Section
Gen er a l Com m en ts. All manipulations were performed
under an atmosphere of nitrogen or argon using standard
Schlenk techniques. Solvents were dried by refluxing over Na/
benzophenone ketyl (THF, toluene, benzene, and diethyl
ether), Mg(OEt)2 (ethanol), or Mg(OMe)2 (methanol) and
distilled before use. Triethylamine was distilled from sodium,
whereas alkynes were used as received. IR spectra were
recorded on a Shimadzu 8100M spectrometer. 1H (270 MHz),
13C{1H} (67.8 MHz), and 31P{1H} (109 MHz) NMR spectra were
recorded in C6D6 on a J EOL EX-270 spectrometer; chemical
shifts are referenced to the signals of the residual nondeuter-
ated benzene at 7.2 ppm (1H), C6D6 at 128.7 ppm (13C), and
PPh3 in CDCl3 at -5.65 ppm (85% H3PO4 ) 0.0 ppm; 31P).
Hydrogen gas evolution was determined by GLC analysis using
Con clu sion
We have demonstrated that the hydrosulfido-bridged
diruthenium complex 1 serves as a useful precursor to
(26) Collman, J . P.; Roper, W. R. J . Am. Chem. Soc. 1965, 87, 4008.
(27) (a) Harris, R. O.; Hota, N. K.; Sadaroy, L.; Yuen, J . M. C. J .
Organomet. Chem. 1973, 54, 259. (b) Knoth, W. H. J . Am. Chem. Soc.
1972, 94, 104.
a
Shimadzu GC-8A gas chromatograph equipped with a
molecular sieve 13X column. Electrochemical measurements
were made with Hokuto Denko instrumentation (HA-501
potentiostat and HB-105 function generator) using a glassy
(28) Mitsui, T.; Inomata, S.; Ogino, H. Inorg. Chem. 1994, 33, 4934.

Dithiolene- and Sulfido-Bridged Ru Complexes
Organometallics, Vol. 17, No. 16, 1998 3435
carbon working electrode; potentials were measured in CH2-
Cl2-0.1 M Bun4NBF4 vs a saturated calomel electrode as the
reference. Elemental analyses were performed on a Perkin-
Elmer 2400II CHN analyzer or at the Elemental Analysis
Laboratory, Department of Chemistry, The University of
Tokyo.
P r ep a r a tion of [(Cp *Ru )4(µ3-S)4] (3). To a toluene solu-
tion (12 mL) of 1 (82.7 mg, 0.136 mmol) was added triethyl-
amine (0.11 mL, 0.79 mmol) at -78 °C, and the mixture was
slowly warmed to room temperature with stirring. The solvent
was then removed in vacuo, and the resultant dark brown solid
was recrystallized from THF-methanol (2 mL/2 mL) at -23
°C, affording 3 as a brown solid (32.3 mg, 44%). 1H NMR: δ
1.77 (s, 60 H, C5Me5; literature value δ 1.7213). Anal. Calcd
for C40H60Ru4S4: C, 44.76; H, 5.63; S, 11.95; Cl, 0. Found: C,
44.62; H, 5.79; S, 11.14; Cl, 0.
Rea ction of 3 w ith HCl. To a solution of 3 (51.4 mg,
0.0478 mmol) in toluene (10 mL) was bubbled HCl gas for 10
s, and the mixture was stirred for 1 h at room temperature.
The dark brown solid precipitated was filtered off, washed with
diethyl ether, and dried in vacuo to give 47.9 mg of [(Cp*Ru)4-
(µ3-S)4]Cl2 (82%).10
Th er m olysis of [Cp *Ir Cl(µ2-SH)2Ir ClCp *] (2a ). A tolu-
ene (10 mL) solution of 2a (84.1 mg, 0.106 mmol) was heated
at reflux for 7 h. The resultant orange suspension was dried,
then extracted with benzene (30 mL). Removal of the solvent
from the extract afforded 39.4 mg of [(Cp*Ir)4(µ3-S)4]2f,29 as an
orange powder (52%). Similar treatment of 2b gave
[(Cp*Rh)4(µ3-S)4]30 in 42% yield.
P r ep a r a tion of [(Cp *Ru )2(µ2-η2:η4-S2C2RR′)] (4). The
following procedure for the preparation of [(Cp*Ru)2(µ2-η2:η4-
S2C2HBut)] (4a ) is representative. To a solution of 1 (409.1
mg, 0.671 mmol) in THF (18 mL) was added triethylamine
(0.55 mL, 4.0 mmol) and ButCCH (0.50 mL, 4.1 mmol) at -78
°C, and the mixture was slowly warmed to room temperature
with stirring. The resultant red solution was evaporated in
vacuo, and the residue was extracted with benzene (20 mL).
Addition of methanol to the concentrated extract gave 4a as
red crystals (183.7 mg, 44%). 1H NMR: δ 5.42 (s, 1 H,
S2C2HBut), 2.05, 1.84 (s, 15 H each, C5Me5), 1.36 (s, 9 H, CMe3).
13C{1H} NMR: δ 122.9, 86.5 (S2C2HBut), 88.6, 83.4 (C5Me5),
37.4 (CMe3), 33.4 (CMe3), 13.3, 13.2 (C5Me5). Anal. Calcd for
H each, C5Me5). 13C{1H} NMR: δ 88.44 (S2C2H2), 88.37, 83.7
(C5Me5), 13.4, 12.3 (C5Me5). Anal. Calcd for C22H32S2Ru2: C,
46.95; H, 5.73. Found: C, 46.57; H, 5.99.
[(Cp *Ru )2(µ2-η2:η4-S2C2P h 2)] (4e). The crude reaction
mixture obtained as described above was extracted with
benzene-hexanes (1:1) and chromatographed on alumina with
benzene-hexanes (1:4). Removal of the solvent from the first
red band and recrystallization from benzene-methanol af-
forded red crystals of 4e, which were washed with a small
amount of hexanes and dried in vacuo (7%). 1H NMR: δ 7.52-
6.99 (m, 10 H, Ph), 2.05, 1.70 (s, 15 H each, C5Me5). Anal.
Calcd for C22H32S2Ru2: C, 57.12; H, 5.64. Found: C, 56.91;
H, 5.67. Evaporation of the solvent from the second dark red
band obtained by using methanol as an eluent afforded 3 in
58% yield.
P r ep a r a t ion of [Cp *R u (CO)(µ2-η2:η4-S2C2R R ′)R u Cp *]
(5). The following procedure for the preparation of [Cp*Ru-
(CO)(µ2-η2:η4-S2C2HBut)RuCp*] (5a) is representative. Through
a solution of 4a (139.6 mg, 0.226 mmol) in THF (10 mL) was
bubbled CO for 5 min, and the mixture was stirred for 15 h at
room temperature. After removal of the solvent in vacuo, the
resultant red solid was recrystallized from benzene-methanol
(0.5 mL/3 mL). The red crystals formed were filtered off,
washed with a small amount of methanol, and dried in vacuo
(112.9 mg, 77%). IR (KBr): 1918 cm-1 (s, νCO). 1H NMR: δ
6.17 (s, 1 H, S2C2HBut), 1.76, 1.67 (s, 15 H each, C5Me5), 1.60
(s, 9 H, CMe3). 13C{1H} NMR: δ 205.2 (CO), 121.9, 84.4 (S2C2-
HBut), 94.2, 88.6 (C5Me5), 38.1 (CMe3), 32.1 (CMe3), 12.7, 10.8
(C5Me5). Anal. Calcd for C27H40OS2Ru2: C, 50.13; H, 6.23.
Found: C, 49.98; H, 6.24.
[Cp*Ru (CO)(µ2-η2:η4-S2C2HTol)Ru Cp*] (5b). Yield: 68%.
IR (KBr): 1910 cm-1 (s, νCO). 1H NMR: δ 7.76, 6.98 (d, 2 H
each, J ) 8.3 Hz, C6H4), 6.58 (s, 1 H, S2C2HTol), 2.12 (s, 3 H,
C6H4Me), 1.67, 1.52 (s, 15 H each, C5Me5). 13C{1H} NMR: δ
204.8 (CO), 139.6, 136.2 (ipso-C), 129.8, 126.5 (o- and m-C),
102.6, 83.8 (S2C2HTol), 94.3, 88.7 (C5Me5), 21.9 (C6H4Me), 11.4,
10.8 (C5Me5). Anal. Calcd for C30H38OS2Ru2: C, 52.92; H,
5.63. Found: C, 52.81; H, 5.77.
[Cp*Ru (CO){µ2-η2:η4-S2C2(COOMe)2}Ru Cp *] (5c). Yield:
89%. IR (KBr): 1929 (s, νCO), 1721, 1696 cm-1 (s, νCdO). 1H
NMR: δ 3.58 (s, 6 H, COOMe), 1.75, 1.51 (s, 15 H each, C5-
Me5). 13C{1H} NMR: δ 204.3 (CO), 172.2 (COOMe), 95.3
(S2C2(COOMe)2), 94.2, 93.4 (C5Me5), 52.7 (COOMe), 11.1, 10.5
(C5Me5). Anal. Calcd for C27H36O5S2Ru2: C, 45.88; H, 5.13.
Found: C, 46.27; H, 5.24.
C
26H40S2Ru2: C, 50.46; H, 6.51. Found: C, 50.03; H, 6.68.
[(Cp *R u )2(µ2-η2:η4-S2C2H Tol)] (4b ). Yield: 75%. 1H
NMR: δ 7.69, 6.94 (d, 2 H each, J ) 8.1 Hz, C6H4), 5.74 (s, 1
H, S2C2HTol), 2.11 (s, 3 H, C6H4Me), 2.08, 1.62 (s, 15 H each,
C5Me5). 13C{1H} NMR: δ 138.0, 136.6 (ipso-C), 129.6, 127.9
(o- and m-C), 104.0, 85.6 (S2C2HTol), 88.8, 83.9 (C5Me5), 21.8
(C6H4Me), 13.3, 11.9 (C5Me5). Anal. Calcd for C29H38S2Ru2:
C, 53.35; H, 5.87. Found: C, 53.07; H, 5.86.
[(Cp *Ru )2{µ2-η2:η4-S2C2(COOMe)2}] (4c). Yield: 39%. IR
(KBr): 1698, 1730 cm-1 (s, νCdO). 1H NMR: δ 3.52 (s, 6 H,
COOMe), 1.90, 1.83 (s, 15 H each, C5Me5). 13C{1H} NMR: δ
171.4 (COOMe), 97.7 (S2C2(COOMe)2), 92.6, 85.5 (C5Me5), 52.7
(COOMe), 13.0, 11.5 (C5Me5). Anal. Calcd for C26H36O4S2-
Ru2: C, 46.00; H, 5.35. Found: C, 45.77; H, 5.52. Complex
4c was also obtained from the reaction of 1 (79.3 mg, 0.130
mmol) and dimethyl acetylenedicarboxylate (60 µL, 0.49 mmol)
in THF (10 mL) at room temperature for 21 h. Recrystalli-
zation from benzene-methanol (1 mL/2 mL) afforded 4c in
19% yield.
P r ep a r a t ion of [(Cp *R u )2(µ3-S)2(µ2-H )R u Cl(P P h 3)2]‚
0.5THF (6‚0.5THF ). To a solution of 1 (45.7 mg, 0.0750
mmol) in THF (10 mL) was added [RuH2(PPh3)4] (87.8 mg,
0.0762 mmol), and the mixture was stirred for 18 h at room
temperature. Evolution of an equimolar amount of H2 was
confirmed by GLC analysis. The resultant brown solution was
reduced to 3 mL, and methanol (10 mL) was layered on the
solution. The dark brown crystals that formed were filtered
off, washed with diethyl ether, and dried in vacuo (51.0 mg,
55%). 1H NMR: δ 7.68-6.99 (m, 30 H, Ph), 2.09, 1.48 (s, 15
2
H each, C5Me5), -27.97 (t, 1 H, J PH ) 14.1 Hz, RuH). 31P-
{1H} NMR: δ 29.5 (s). Anal. Calcd for C58H65O0.5P2S2ClRu3:
C, 56.41; H, 5.31. Found: C, 56.58; H, 5.57.
P r ep a r a t ion of [(Cp *R u )2(µ3-S)2(µ2-H )R u H (P P h 3)2]‚
THF (7‚THF ). To a suspension of 6‚0.5THF (33.9 mg, 0.0283
mmol) in ethanol (8 mL) was added NaBH4 (22.1 mg, 0.584
mmol), and the mixture was stirred for 8 h at 50 °C. After
removal of the solvent in vacuo, the resultant brown solid was
extracted with benzene (8 mL). The extract was evaporated
to dryness and recrystallized from THF-methanol (1 mL/3
mL). The dark brown crystals that formed were filtered off,
washed with methanol, and dried in vacuo (30.3 mg, 89%). IR
(KBr): 1919 cm-1 (w, νRuH). 1H NMR: δ 7.70-6.97 (m, 30 H,
[(Cp *R u )2(µ2-η2:η4-S2C2H 2)] (4d ). Acetylene gas was
bubbled for 10 min into a mixture of 1 and triethylamine in
THF at -78 °C. The mixture was treated as described above,
and recrystallization from methanol at -23 °C afforded 4d in
60% yield. 1H NMR: δ 5.12 (s, 2 H, S2C2H2), 2.06, 1.73 (s, 15
(29) Herberhold, M.; J in, G.-X.; Milius, W. Chem. Ber. 1995, 128,
557.
(30) Skaugset, A. E.; Rauchfuss, T. B.; Wilson, S. R. Organometallics
1990, 9, 2875.
2
Ph), 1.89 (s, 30 H, C5Me5), -16.32 (t, 2 H, J PH ) 22.6 Hz,
RuH). 31P{1H} NMR: δ 61.9 (s). Anal. Calcd for C60H70OP2S2-
Ru3: C, 58.28; H, 5.71. Found: C, 58.33; H, 5.87.

3436 Organometallics, Vol. 17, No. 16, 1998
Ta ble 3. X-r a y Cr ysta llogr a p h ic Da ta for 4a , 5a , 6‚0.5THF , 7‚THF , a n d 8
Kuwata et al.
4a
5a
6‚0.5THF
7‚THF
8
formula
fw
C
26H40S2Ru2
C27H40OS2Ru2
646.87
C58H65P2S2ClRu3O0.5
1234.88
orthorhombic
Pbca (No. 61)
dark brown
0.1 × 0.2 × 0.6
12.749(8)
22.486(9)
36.846(7)
90
90
90
10562(6)
8
1.553
C60H70P2S2Ru3O
1236.49
triclinic
P1h (No. 2)
dark brown
0.2 × 0.3 × 0.4
12.346(2)
21.675(4)
11.018(2)
94.58(2)
101.39(2)
73.71(2)
2773.5(9)
2
C40H45Ru3O2S2P
956.10
618.86
monoclinic
P21/n (No. 14)
dark red
0.3 × 0.5 × 0.7
11.683(6)
16.509(5)
14.401(3)
90
106.22(3)
90
2667(1)
4
cryst syst
space group
cryst color
cryst dimens, mm
a, Å
triclinic
P1h (No. 2)
dark red
0.1 × 0.3 × 0.6
10.745(2)
14.461(2)
10.729(2)
104.59(1)
113.87(1)
69.19(1)
1413.7(4)
2
monoclinic
P21/n (No. 14)
dark brown
0.1 × 0.2 × 0.5
9.738(4)
30.742(4)
13.406(4)
90
97.61(3)
90
3977(2)
4
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
Dc, g cm-3
F(000), e
1.541
1264
1.520
660
1.481
1264
1.596
1920
5024
µ(Mo KR), cm-1
reflns measd
no. of unique reflns
transmission factors
no. of data used (I > 3σ(I))
no. variables
Ra
13.00
+h, +k, (l
3637
0.9127-0.9987
2956
272
0.036
0.027
12.33
+h, (k, (l
4964
0.6860-1.0000
4128
290
0.026
0.021
10.76
+h, +k, +l
7625
0.8207-1.0000
4161
665
0.043
0.038
9.79
+h, (k, (l
8795
0.8389-1.0000
6731
620
0.032
0.025
13.02
+h, +k, (l
7159
0.5395-1.0000
4048
314
0.058
0.051
a
Rw
GOFb
3.62
0.95
2.17
0.37
1.52
0.60
2.00
0.62
2.39
1.27
max residual, e Å-3
a
2
b
R ) ∑||Fo| - |Fc||/∑|Fo|; Rw ) [∑w(|Fo| - |Fc|)2/∑wFo
]
1/2; w ) 1/σ2(Fo). GOF ) [∑w(|Fo| - |Fc|)2/(Nobs - Nparms)]1/2
.
niques for 4a , 5a , and 7‚THF, while for 6‚0.5THF, the carbon
and oxygen atoms in the solvating THF molecule were refined
isotropically. For 8, each of three phenyl rings was placed at
the two disordered positions as rigid groups and refined
isotropically with a 50% occupancy. The hydrogen atoms of
the hydrido ligand in 6‚0.5THF and 7‚THF were found in the
final difference Fourier map, while all other hydrogen atoms
except those in the solvating THF molecule in 6‚0.5THF were
placed at calculated positions. The positional parameters of
the hydrogen atoms in the hydrido ligands in 7‚THF were
included in the final stages of refinements, whereas all other
hydrogen atoms were included with fixed parameters. The
atomic scattering factors were taken from ref 33, and anoma-
lous dispersion effects were included; the values of ∆f ′ and
∆f ′′ were taken from ref 34.
P r ep a r a tion of [(Cp *Ru )2(µ3-S)2Ru (CO)2(P P h 3)] (8). To
a solution of 7‚THF (50.5 mg, 0.0408 mmol) in toluene (10 mL)
was bubbled CO for 5 min at room temperature, and the
mixture was stirred at 50 °C for 16 h. After removal of the
solvent in vacuo, the resultant dark brown solid was recrystal-
lized from benzene-methanol (1 mL/5 mL). The dark brown
crystals that formed were filtered off, washed with methanol,
and dried in vacuo (12.8 mg, 35%). IR (KBr): 1970, 1921 (s,
ν
CO). 1H NMR: δ 7.74-6.97 (m, 15 H, Ph), 1.85 (s, 30 H, C5-
Me5). 31P{1H} NMR: δ 48.9 (s). Anal. Calcd for C40H45O2-
PS2Ru3: C, 50.25; H, 4.74. Found: C, 50.41; H, 4.90.
X-r a y Diffr a ction Stu d ies. Single crystals suitable for
X-ray analyses were sealed in glass capillaries under an inert
atmosphere and mounted on a Rigaku AFC7R four-circle
diffractometer equipped with a graphite-monochromatized Mo
KR source (λ ) 0.7107 Å). Orientation matrixes and unit cell
parameters were determined by least-squares treatment of 25
machine-centered reflections with 25° < 2θ < 40°. The data
collection was performed at room temperature using the ω-2θ
scan technique at a rate of 32 deg min-1 to a maximum 2θ
value of 45° (for 4a and 6‚0.5THF) and 50° (for 5a , 7‚THF,
and 8). The intensities of three check reflections were
monitored every 150 reflections, which showed no significant
decay during data collections. Intensity data were corrected
for Lorentz-polarization effects and for absorption (ψ scans).
Details of crystal and data collection parameters are sum-
marized in Table 3.
Ack n ow led gm en t. This work was supported by a
Grant-in-Aid for Specially Promoted Research (Grant
No. 09102004) from the Ministry of Education, Science,
Sports, and Culture of J apan.
Su p p or tin g In for m a tion Ava ila ble: Tables of atomic
coordinates and equivalent isotropic thermal parameters,
anisotropic thermal parameters, and full bond lengths and
angles for 4a , 5a , 6‚0.5THF, 7‚THF, and 8 (71 pages).
Ordering information is given on any current masthead page.
Structure solution and refinements were carried out by
using the teXsan program package.31 The heavy atom posi-
tions were determined by Patterson methods program (DIRDIF-
PATTY),32 and the remaining non-hydrogen atoms were found
by subsequent Fourier syntheses. All non-hydrogen atoms
were refined anisotropically by full-matrix least-squares tech-
OM980214D
(32) PATTY: Beurskens, P. T.; Admiraal, G.; Beurskens, G.; Bos-
man, W. P.; Garcia-Granda, S.; Gould, R. O.; Smits, J . M. M.; Smykalla,
C. The DIRDIF program system; Technical Report of the Crystal-
lography Laboratory: University of Nijmegen, The Netherlands, 1992.
(33) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, England, 1974; Vol. IV.-
(31) teXsan: Crystal Structure Analysis Package; Molecular Struc-
ture Corp.: The Woodlands, TX, 1985 and 1992.-
(34) International Tables for X-ray Crystallography; Kluwer Aca-
demic Publishers: Boston, MA, 1992; Vol. C.