Synthesis and structures of heterobimetallic Ir2M (M=Pd, Pt) sulfido clusters and their catalytic activity for regioselective addition of alcohols to internal 1-aryl-1-alkynes

Article abstract of DOI:10.1016/S0022-328X(00)00619-7

The heterobimetallic trinuclear suffido clusters [(Cp*Ir)₂(μ₃-S)₂MCl₂] (M = Pd (3), Pt (4); Cp* = η⁵-C₅Me₅) were synthesized from the dinuclear hydrogensulfido complex [Cp*IrCl(μ

Full text of DOI:10.1016/S0022-328X(00)00619-7

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 620 (2001) 69–79
Synthesis and structures of heterobimetallic Ir2M (MꢀPd, Pt)
sulfido clusters and their catalytic activity for regioselective
addition of alcohols to internal 1-aryl-1-alkynes
Dai Masui a, Takuya Kochi a, Zhen Tang a, Youichi Ishii a, Yasushi Mizobe b,
Masanobu Hidai a,*,1
a Department of Chemistry and Biotechnology, Graduate School of Engineering, Uni6ersity of Tokyo, Hongo, Bunkyo-ku,
Tokyo 113-8656, Japan
b Institute of Industrial Science, Uni6ersity of Tokyo, Roppongi, Minato-ku, Tokyo 106-8558, Japan
Received 28 June 2000; received in revised form 30 August 2000; accepted 5 September 2000
Abstract
The heterobimetallic trinuclear sulfido clusters [(Cp*Ir)2(m3-S)2MCl2] (M=Pd (3), Pt (4); Cp*=h5-C5Me5) were synthesized
from the dinuclear hydrogensulfido complex [Cp*IrCl(m-SH)2IrCp*Cl] (2) and [MCl2(COD)] (COD=cycloocta-1,5-diene), while
the reaction of 2 with [Pd(PPh3)4] afforded the cationic trinuclear cluster [(Cp*Ir)2(m3-S)2PdCl(PPh3)]Cl (5). Clusters 3 and 4
reacted with PPh3 to give a series of mono and dicationic clusters including 5, while the dicationic clusters [(Cp*Ir)2(m3-
S)2M(dppe)][BPh4]2 (M=Pd (9), Pt (10); dppe=Ph2PCH2CH2PPh2) were obtained by the reaction with dppe followed by anion
metathesis. The molecular structures of 5·CH2Cl2, 9·CH3COCH3, and 10·CH3COCH3 were determined by X-ray crystallography.
Clusters 3 and 4 were found to catalyze the addition of alcohols to alkynes to give the corresponding acetals. Internal
1-aryl-1-alkynes were transformed by cluster 3 into the corresponding 2,2-dialkoxy-1-arylalkanes with high regioselectivity up to
99:1, while cluster 4 was a much less regioselective catalyst. © 2001 Elsevier Science B.V. All rights reserved.
Keywords: Palladium; Platinum; Iridium; Cluster; Catalytic addition; Crystal structure
1. Introduction
able number of metal–sulfur clusters containing first
transition series metals and molybdenum have so far
been synthesized and structurally characterized. In con-
trast, few studies on transition metal–sulfur multinu-
clear complexes toward organic synthesis have been
performed [3], although they are anticipated to provide
stable multimetallic reaction sites owing to the strong
bridging ability of sulfur ligands to prevent fragmenta-
tion of the multimetallic cores. In this context, we have
been engaged in developing multinuclear complexes of
Groups 8–10 noble metals with bridging sulfur ligands
and have uncovered, that such complexes in fact exhibit
intriguing reactivities toward a wide variety of organic
substrates [4–6]. One typical example is the cubane-
type PdMo3S4 cluster [PdMo3(m3-S)4(tacn)3Cl][PF6]3 (1;
tacn=1,4,7-triazacyclononane), which behaves as an
excellent catalyst for the stereoselective addition reac-
tions of alcohols or carboxylic acids to electron defi-
The chemistry of multinuclear transition metal com-
plexes has recently been a subject of intensive research
activity, because their multimetallic coordination sites
are expected to facilitate unique chemical transforma-
tions through cooperative or successive interaction of
the metal centers with substrate molecules [1]. In partic-
ular, multinuclear complexes with sulfur-based ligands
are of special interest in connection with some biochem-
ical reactions effected by metalloproteins and industrial
processes by metal–sulfide catalysts [2], and a consider-
* Corresponding author. Fax: +81-471-239362.
E-mail address: hidai@mail.rs.noda.sut.ac.jp (M. Hidai).
1 Present address: Department of Materials Science and Technol-
ogy, Faculty of Industrial Science and Technology, Science Univer-
sity of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.
0022-328X/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(00)00619-7

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D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
cient alkynes and the lactonization of alkynoic acids [6].
The catalytic activities as well as the selectivities of
cluster 1 in such reactions are far superior to those of
conventional mononuclear palladium complexes. How-
ever, cluster 1 was not effective for the intermolecular
addition of alcohols to nonactivated alkynes.
(1)
Recently, we have synthesized a series of dinuclear
hydrogensulfido complexes such as [Cp*MCl(m-
SH)2MCp*Cl] (M=Ru, Rh, Ir (2); Cp*=h5-C5Me5)
[7] and [Cp2Ti(m-SH)2RuCp*Cl] (Cp=h5-C5H5) [8] and
demonstrated that they are used as versatile starting
materials for the construction of homo and het-
erometallic, tri, tetra, and pentanuclear sulfido clusters
containing the Cp*M(m3-S)2MCp* unit(s) [7b,8,9]. In a
previous communication, we have reported that the
mixed-metal trinuclear clusters [(Cp*Ir)2(m3-S)2MCl2]
(M=Pd (3), Pt (4)) readily derived from complex 2
exhibit good catalytic activity for the addition of alco-
hols to nonactivated alkynes to give the corresponding
acetals, and further, high regioselectivity is observed in
the reactions of internal 1-aryl-1-alkynes by 3 [10].
Although a few transition metal compounds have been
known to effect this type of addition of alcohols to
alkynes [11], no regioselective catalyst has been devel-
oped for the reactions of internal alkynes. In this paper,
we describe the synthesis and full characterization of
the Ir2M sulfido clusters (M=Pd, Pt) including 3 and 4
as well as the catalytic addition of alcohols to nonacti-
vated alkynes by 3 and 4.
On the other hand, reaction of 2 with [Pd(PPh3)4] at
room temperature (r.t.) afforded the cationic trinuclear
cluster [(Cp*Ir)2(m3-S)2PdCl(PPh3)]Cl (5) in 68% yield.
In this case, the Pd(0) atom in [Pd(PPh3)4] is considered
to be oxidized to the formal Pd(II) center of 5. The
GLC analysis of the gaseous phase indicated that H2
was evolved during the reaction in 47% yield based on
the complex 2 employed, which suggests the stoi-
1
chiometry shown in Eq. (2). In the H-NMR spectrum,
cluster 5 exhibited one Cp* signal at l 2.09 and Ph
signals at l 7.46–7.61 with the relative intensity ratio of
2:1. The 31P{1H}-NMR spectrum showing a singlet at l
28.2 is also consistent with the formulation. In contrast,
treatment of complex 2 with [Pt(PPh3)4] did not lead to
the formation of the corresponding mixed-metal trinu-
clear cluster. The only cluster species identified by the
1H-NMR analysis of the crude reaction mixture was the
cubane-type tetrairidium cluster [(Cp*Ir)4(m3-S)4], which
we previously described to be formed by treatment of 2
with a base [7c]. We have also observed that the
2. Results and discussion
hydrogensulfido-bridged
diruthenium
complex
[Cp*RuCl(m-SH)2RuCp*Cl] reacts with [Pd(PPh3)4] to
produce the tetranuclear cluster [(Cp*Ru)2{Pd(PPh3)}2-
(m3-S)2(m-Cl)]Cl [12]. The structures of the cluster cores
constructed from the dinuclear hydrogensulfido com-
plexes are greatly affected by the combination of the
metal elements involved.
2.1. Synthesis and characterization of Ir2M sulfido
clusters (M=Pd, Pt)
When complex 2 was allowed to react with a small
excess of [PdCl2(COD)] (COD=cycloocta-1,5-diene) at
50°C in THF, the Ir2Pd trinuclear cluster 3 was ob-
tained in good yield as dark green crystals (Eq. (1)). A
similar reaction of 2 with [PtCl2(COD)] gave the
analogous Ir2Pt cluster 4. Although single crystals of 3
and 4 suitable for crystallographic analysis could not be
obtained, these clusters were characterized by spectro-
scopic and analytical data as well as X-ray diffraction
studies of their phosphine derivatives (vide infra). In
(2)
The molecular structure of 5·CH2Cl2 was confirmed
by X-ray diffraction study. An ORTEP drawing for the
cationic part in 5·CH2Cl2 is depicted in Fig. 1, and
selected bond distances and angles are listed in Table 1.
The cluster is composed of a 48 e− triangular core,
which is capped by two m3-S ligands from both sides,
and possesses a crystallographically imposed mirror
plane containing the Pd(1), Cl(1), S(1), S(2), and P(1)
1
the H-NMR spectrum of cluster 3, only one singlet
was observed at l 2.15 attributable to the Cp* protons.
1
A very similar H-NMR spectrum with a singlet at l
2.14 was obtained for cluster 4. These data imply that
in each case the COD ligand is replaced by the metal-
loligand Cp*Ir(m3-S)2IrCp* derived from complex 2 to
form the trinuclear cluster.

D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
71
atoms. The palladium atom adopts a square planar
different PdꢁS bond distances (Pd(1)ꢁS(1), 2.362(4);
,
geometry typical of a Pd(II) center. The Ir(1)ꢁIr(1*)
Pd(1)ꢁS(2), 2.293(4) A) because of the stronger trans
,
and Ir(1)ꢁPd(1) distances are 2.9002(9) and 3.001(1) A,
influence of the phosphine ligand than that of the
chloro ligand.
respectively. Although the latter is longer than the
reported IrꢁPd single bond distances including the dis-
To gain additional information about the electronic
state of the palladium center in cluster 3 and 5, an XPS
analysis was performed. The Pd-3d5/2 binding energy
for 3 was found to be 336.8 eV, which is considerably
lower than those of the Pd(II) complexes including
[PdCl2(PhCN)2] (338.1 eV), [PdCl2(PPh3)2] (338.0 eV),
and [PdCl2(PhSCH2CH2CH2SPh)] (338.3 eV) but is
somewhat higher than that of the Pd(0) complex
[Pd(PPh3)4] (335.9 eV), while the value for the cationic
cluster 5 (337.8 eV) was not unusual as a Pd(II) species.
The result of the XPS analysis suggests that the palla-
dium center in 3 is substantially electron rich compared
with those in common mononuclear Pd(II) complexes.
The electron rich nature of the palladium center in 3 is
reflected in the facile dissociation of the chloro ligand(s)
to form cationic clusters by reaction with phosphines
(vide infra). It should also be noted that the Pd-3d5/2
binding energies for the cubane-type tetranuclear
sulfido clusters 1 (336.0 eV) and [{Pd(PPh3)}2{Mo-
(S2CNEt2)}2(m3-S)4] (336.5 eV) [15] and the trinuclear
cluster [Pd(PPh3)(m-S)2{Mo(S2CNEt2)}2(m-S)2] (336.4
eV) [15] are close to that of 3, although the oxidation
states of the palladium atoms in these clusters still
remain ambiguous. Thus, the palladium atom in 1 is
regarded as Pd(0) rather than Pd(II) on the basis of the
molecular orbital calculations [16], whereas the catalytic
activities observed with 1 are diagnostic of a Pd(II)
species [6b–d].
,
tance (2.694(2) A) in [PdIr(CO)Cl(m-dpmp)2][PF6]2
(dpmp=PPh(CH2PPh2)2) [13], both IrꢁIr and IrꢁPd
bonds are considered to have metal–metal bonding
interactions in terms of the effective atomic number
(EAN) rule. It is known that the divalent Group 10
metal atoms with the square planar geometry have a
high-lying atomic pz orbital perpendicular to the coor-
dination plane, and its contribution to the metal–metal
bonding is often small [14]. This may be the reason why
the IrꢁPd bonds in 5 are elongated. The two m3-S
ligands are unsymmetrically bound to the core with the
2.2. Reactions of clusters 3 and 4 with phosphine
ligands
As described above, the Ir2Pd cluster with a PPh3
ligand 5 was prepared directly from complex 2, whereas
the analogous Ir2Pt cluster could not be obtained by a
similar synthetic method. We therefore investigated lig-
and substitution reactions of clusters 3 and 4 with
phosphines. When nearly equimolecular amounts of
cluster 3 and PPh3 were dissolved in CDCl3, the exclu-
Fig. 1. Structure of the cationic part in 5·CH2Cl2. Hydrogen atoms
are omitted for clarity. Thermal ellipsoids are shown at the 50%
probability level.
Table 1
,
Selected bond distances (A) and angles (°) for 5·CH2Cl2
1
sive formation of cluster 5 was confirmed by H- and
31P{1H}-NMR. However, substitution of the second
chloro ligand by excess PPh3 occurred only to a minor
extent. Thus, on treatment of 3 with 3.5 equivalents of
PPh3, a new species 6 showing a 31P{1H}-NMR signal
at l 20.5 (s) emerged as the minor product (5:6=
73:27). This minor species 6 is tentatively formulated as
the dicationic cluster [(Cp*Ir)2(m3-S)2Pd(PPh3)2]Cl2, but
attempts to isolate 6 in a pure form failed.
Bond distances
Ir(1)ꢁIr(1*)
Ir(1)ꢁPd(1)
Ir(1)ꢁS(1)
Ir(1)ꢁS(2)
2.9002(9)
3.001(1)
2.295(3)
2.279(3)
Pd(1)ꢁCl(1)
Pd(1)ꢁS(1)
Pd(1)ꢁS(2)
Pd(1)ꢁP(1)
2.346(4)
2.362(4)
2.293(4)
2.281(4)
Bond angles
Ir(1*)ꢁIr(1)ꢁPd(1)
Ir(1)ꢁPd(1)ꢁIr(1*)
S(1)ꢁIr(1)ꢁS(2)
Cl(1)ꢁPd(1)ꢁS(1)
Cl(1)ꢁPd(1)ꢁS(2)
Cl(1)ꢁPd(1)ꢁP(1)
S(1)ꢁPd(1)ꢁS(2)
61.11(1)
57.79(3)
84.3(1)
93.3(1)
175.8(1)
90.9(1)
82.5(1)
S(1)ꢁPd(1)ꢁP(1)
S(2)ꢁPd(1)ꢁP(1)
Ir(1)ꢁS(1)ꢁIr(1*)
Ir(1)ꢁS(1)ꢁPd(1)
Ir(1)ꢁS(2)ꢁIr(1*)
Ir(1)ꢁS(2)ꢁPd(1)
175.9(1)
93.4(1)
78.4(1)
80.2(1)
79.1(1)
82.1(1)
In contrast, the stepwise and complete conversion to
the monosubstituted and disubstituted clusters was ob-
served in the reaction of cluster 4 with PPh3. Thus, on
dissolving cluster 4 and one equivalent of PPh3 in

72
D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
31P{1H}-NMR spectrum. Cluster 8 could be isolated as
the [BPh4]− salt [(Cp*Ir)2(m3-S)2Pt(PPh3)2][BPh4]2 (8%).
Treatment of 3 and 4 with 1.2 equivalents of dppe
(dppe=Ph2PCH2CH2PPh2) caused spontaneous color
change from green to purple, and further anion
metathesis with NaBPh4 afforded the dicationic clusters
[(Cp*Ir)2(m3-S)2M(dppe)][BPh4]2 (M=Pd (9), Pt (10))
(Eq. (3)). The molecular structures of these clusters
were unambiguously established by X-ray crystallog-
raphy. ORTEP drawings for 9·CH3COCH3 and
10·CH3COCH3 are given in Fig. 2, and selected bond
distances and angles are summarized in Table 2. Both
clusters have a triangular core with two m3-S caps,
which is closely related to that of cluster 5. In each
,
crystal, the two IrꢁPd (2.9532(9), 3.032(1) A) or IrꢁPt
,
(2.957(1), 3.038(1) A) distances are not equivalent, but
no special nonbonding interaction is observed within
these cations. We consider that the inequality of the
IrꢁM distances is most probably due to crystal packing.
These results provide additional support to the molecu-
lar structures of the Ir2Pd and Ir2Pt clusters 3 and 4.
(3)
Table 2
,
Selected bond distances (A) and angles (°) for 9·CH3COCH3 and
10·CH3COCH3
9·CH3COCH3
(M=Pd)
10·CH3COCH3
(M=Pt)
Bond distances
Ir(1)ꢁIr(2)
Ir(1)ꢁM(1)
Ir(2)ꢁM(1)
Ir(1)ꢁS(1)
Ir(1)ꢁS(2)
Ir(2)ꢁS(1)
Ir(2)ꢁS(2)
M(1)ꢁS(1)
M(1)ꢁS(2)
M(1)ꢁP(1)
M(1)ꢁP(2)
2.8758(9)
2.9532(9)
3.032(1)
2.299(3)
2.289(3)
2.286(3)
2.278(3)
2.347(3)
2.355(3)
2.260(3)
2.266(3)
2.888(1)
2.957(1)
3.038(1)
2.298(4)
2.309(5)
2.301(5)
2.303(5)
2.362(5)
2.347(4)
2.256(5)
2.252(4)
Fig. 2. Structures of the cationic parts in 9·CH3COCH3 (a) and
10·CH3COCH3 (b). Hydrogen atoms are omitted for clarity. Thermal
ellipsoids are shown at the 50% probability level.
CDCl3, a new complex showing singlets at l 2.06 (Cp*)
in the H-NMR spectrum and at l 12.7 (JPtꢁP=3945
Bond angles
1
Ir(2)ꢁIr(1)ꢁM(1)
Ir(1)ꢁIr(2)ꢁM(1)
Ir(1)ꢁM(1)ꢁIr(2)
S(1)ꢁIr(1)ꢁS(2)
S(1)ꢁIr(2)ꢁS(2)
S(1)ꢁM(1)ꢁS(2)
S(1)ꢁM(1)ꢁP(1)
S(1)ꢁM(1)ꢁP(2)
S(2)ꢁM(1)ꢁP(1)
S(2)ꢁM(1)ꢁP(2)
P(1)ꢁM(1)ꢁP(2)
62.67(2)
59.91(2)
57.42(2)
85.42(9)
86.00(9)
82.89(9)
173.1(1)
95.9(1)
62.61(3)
59.80(3)
57.58(3)
85.8(2)
85.9(2)
83.5(2)
175.6(2)
95.8(2)
95.6(2)
173.9(2)
85.5(2)
Hz) in the 31P{1H}-NMR spectrum was formed as the
major product. This species is characterized as the
monocationic cluster [(Cp*Ir)2(m3-S)2PtCl(PPh3)]Cl (7)
by analogy to the reaction of 3. Further addition of one
equivalent of PPh3 to the above solution led to disap-
pearance of cluster 7, and the cluster [(Cp*Ir)2(m3-
S)2Pt(PPh3)2]Cl2 (8) was formed as the only detectable
product, which exhibited singlets at l 2.08 (Cp*) in the
1H-NMR spectrum and at l 2.9 (JPtꢁP=3685 Hz) in the
96.3(1)
175.1(1)
85.4(1)

D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
73
Table 3
Catalytic addition of MeOH to 1-phenyl-1-propyne a
Catalyst
Conversion (% b)
Yield (% c)
12a:13a d
[(Cp*Ir)2(m3-S)2PdCl2] (3)
[PdCl2(PhSCH2CH2CH2SPh)]
[(Ph3P)(PhS)Pd(m-SPh)]2
[Cp*IrCl(m-SH)2IrCp*Cl] (2)
[IrCl(COD)]2
\99
28
2.5
3
30
33
2
23
\99
1.5
(88)
0
98:2
0
0
6
0
0
0
(35:65)
74:26
[Cp*IrCl(m-Cl)2IrCp*Cl]+[PdCl2(COD)] e
[Pd(PPh3)(m-S)2{W(S2CNEt2)}2(m-S)2]
[(Cp*Ru)2Pd2(m3-S)2(SPri)(m-SPri)(PPh3)]
[(Cp*Ir)2(m3-S)2PtCl2] (4)
(96)
0
[Pt(PPh3)(m-S)2{W(S2CNEt2)}2(m-S)2]
a For reaction conditions, see Section 3.
b Determined by GLC.
c GLC (isolated) yield.
d Determined by 1H-NMR (GLC).
e 56 mmol each.
Reactions of 3 and 4 with other ligands such as CO
and isocyanides were also investigated, but in most
cases isolable products were not obtained. However,
treatment of cluster 4 with an equimolecular amount of
tBuNC followed by anion metathesis with KPF6 yielded
[(Cp*Ir)2(m3-S)2PtCl(CNtBu)][PF6] (11). The IR spec-
trum of 11 exhibited a characteristic w(CN) band at
2203 cm−1, which is comparable to the values reported-
for Pt(II) isocyanide complexes such as trans-
[Pt(C3H5)(C5H5)(CNtBu)2] (2188 cm−1) [17]. Other
spectral features of 11 as well as analytical data are in
agreement with the formulation.
[11a], [AuMe(PPh3)]ꢁHOTf (OTf=OSO2CF3) [11b],
[PtCl2(phosphine)2]ꢁAgOTf [11c], and [RuCl{HB(pz)3}-
(COD)] (pz=pyrazol-1-yl) [11d] have been reported to
effect the intermolecular addition of alcohols to nonac-
tivated alkynes, but no regioselective reaction of inter-
nal alkynes has been observed. More recently, a
ruthenium-catalyzed hydration of 1-alkynes to give the
corresponding aldehydes has been reported [18]. How-
ever, this reaction is considered to proceed via a vinyli-
dene complex and has not been applied to internal
alkynes.
2.3. Catalytic addition of alcohols to alkynes
Having new Ir2Pd and Ir2Pt clusters 3 and 4 in hand,
we turned our attention to their catalytic activity for
the addition of alcohols to nonactivated alkynes. When
phenylacetylene was allowed to react in MeOH at 50°C
in the presence of a catalytic amount of 3, two isomeric
acetals, 1,1-dimethoxy-2-phenylethane and 1,1-dime-
thoxy-1-phenylethane, were formed in the ratio of 13:87
in 50% isolated total yield. A similar reaction of 1-oc-
tyne gave 2,2-dimethoxyoctane in 55% isolated yield as
the sole product. In these reactions, the Markovnikov
type products were obtained predominantly.
(4)
In contrast, the reaction of 1-phenyl-1-propyne with
MeOH in the presence of cluster 3 gave rise to forma-
tion of 2,2-dimethoxy-1-phenylpropane (12a, R1=R=
Me, R2=H) and 1,1-dimethoxy-1-phenylpropane (13a,
R1=R=Me, R2=H) in the ratio of 98:2 (Eq. (4)). No
other products such as enol ethers and ketones were
detected by GLC. Further purification of the products
by column chromatography and bulb-to-bulb distilla-
tion afforded 12a and 13a in 88% combined yield. The
highly selective formation of 12a is of special interest.
Several transition metal catalysts including Na[AuCl4]
Various complexes related to 3 have been employed
as the catalyst for the addition reaction of MeOH to
1,1-phenyl-1-propyne (Table 3). Neither monometallic
palladium complexes with sulfur donor ligands nor
iridium complexes including 2 were effective. The com-
bined use of [Cp*IrCl(m-Cl)2IrCp*Cl] and [PdCl2-
(COD)] failed to show catalytic activity. In addition, it
was confirmed that cluster 3 can be recovered in 85%
yield after the catalytic reaction. On the basis of these
results, we are inclined to believe that the catalysis is

74
D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
performed not by the monometallic palladium or irid-
ium species formed by fragmentation of cluster 3 but by
the Ir2Pd cluster whose core structure is retained during
the reaction. On the other hand, the Ir2Pt cluster 4
displayed good catalytic activity for the addition reac-
tion, but the regioselectivity was much lower than that
of 3. Efforts to improve the catalytic activity of 3 by
using an additive were not successful. Addition of PPh3
or NEt3 to the reaction mixture inhibited the catalytic
activity of 3. Several other heterobimetallic sulfido clus-
ters containing palladium or platinum were also exam-
ined as the catalyst, but none of them showed good
catalytic activity. The Ir2MS2 core (M=Pd, Pt) seems
to be effective for the addition of MeOH to 1-phenyl-1-
propyne.
13 (Eq. (4)). Regioselective addition of EtOH to 1-
phenyl-1-propyne was similarly achieved by the cataly-
sis of 3, although the reaction rate was lowered. In
contrast to alkynes, alkenes such as styrene and 1-
phenyl-1-propene did not react with MeOH at 50°C.
The results of the reactions of various internal 1-aryl-1-
alkynes are listed in Table 4.
From the reactions of 1-phenyl and 1-chlorophenyl-
1-alkynes, the corresponding acetals 12 were obtained
in high selectivity. However, introduction of an electron
donating substituent to the p-position of the phenyl
group of the substrate alkyne decreased the regioselec-
tivity. This observation indicates that the regiochem-
istry is controlled by the electronic effect of the aryl
group, although the unexpectedly high regioselectivity
of 3 has not been fully understood. As a related system,
it has been proposed that the regiochemistry in the
reaction of the cationic palladium complex [Pd(PNP)-
(CH2ꢀCHPh)]2+ (PNP=2,6-bis((diphenylphosphino)-
methyl)pyridine) with dimethylamine to give the benzyl-
palladium complex [Pd(PNP)(CHPhCH2NMe2)]+ can
be explained on steric grounds [19]. However, the selec-
tivity of the present reaction cannot be accounted for
by similar steric effects, because the reaction of phenyl-
acetylene gave 1,1-dimethoxy-1-phenylethane predomi-
nantly (vide supra).
It is well-known that hydration of alkynes is pro-
moted by various transition metal compounds [20].
However, the reaction of 1-phenyl-1-propyne in ace-
tone–water (4:1) in the presence of cluster 3 resulted in
recovery of the starting alkyne. Therefore, it is unlikely
that the above acetal formation involves the hydration
of an alkyne with fortuitous water to form the corre-
sponding ketones followed by the condensation with
MeOH. Considering the fact that the chloro ligands in
3 undergo facile substitution reactions, the catalytic
cycle for the formation of 12 is presumed to be initiated
by replacement of the chloro ligand at the palladium
center in 3 with an alkyne molecule. However, attempts
to detect an intermediate cluster formed from 3 and
1-phenyl-1-propyne were unsuccessful. The nucleophilic
attack of an alcohol molecule on the coordinated
alkyne followed by the protonolysis of the resultant
alkoxyvinyl cluster produces a vinyl ether, which is
further converted to 12 by the addition of a second
alcohol molecule (Scheme 1). In fact, addition of
MeOH to PhCHꢀC(OMe)Me was found to be cata-
lyzed by cluster 3 to afford 12a in 86% yield under the
same conditions. Although the details of the reaction
mechanism remain to be elucidated, it is noteworthy
that the palladium center in the heterometallic sulfido
cluster 3 works as a specifically active and regioselective
reaction site for the acetal formation from nonactivated
internal 1-aryl-1-alkynes and alcohols. Further studies
on heterometallic sulfido clusters including 3 and 4
toward catalytic organic synthesis are under
investigation.
Cluster 3 also worked as a regioselective catalyst for
the addition of MeOH to other internal 1-aryl-1-alky-
nes to give the corresponding acetals 12 in preference to
Table 4
Catalytic addition of alcohols to alkynes by cluster 3 a
Alkyne
Alcohol Conversion Isolated yield 12:13 c
(%) b
(%)
PhCꢂCMe
PhCꢂCMe
PhCꢂCEt
PhCꢂCBun
p-ClC6H4CꢂCMe
m-ClC6H4CꢂCMe
p-TolCꢂCMe
MeOH \99
88
89
81
65
95
70
82
59
98:2
97:3
99:1
98:2
97:3
99:1
91:9
66:34
EtOH
93
MeOH \99
MeOH \99
MeOH \99
MeOH \99
MeOH \99
d
p-MeOC6H4CꢂCMe MeOH \99
a For reaction conditions, see Section 3.
b Determined by GLC.
c Determined by 1H-NMR.
d Alkyne, 1.12 mmol (S/C=20); 72 h.
Scheme 1.

D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
75
3. Experimental
filtration and recrystallized from CH2Cl2–ether to af-
ford [(Cp*Ir)2(m3-S)2PtCl2] (4) as dark green crystals (48
1
mg, 0.049 mmol, 64% yield). H-NMR (CDCl3): l 2.14
(s, 30H, Cp*). Anal. Calc. for C20H30Cl2Ir2PtS2: C,
24.39; H, 3.07. Found: C, 24.42; H, 3.17%.
3.1. General considerations
All manipulations were performed under a nitrogen
atmosphere using standard Schlenk tube techniques.
Complexes 1 [6a,b] and 2 [7b,c] were prepared accord-
ing to the method described previously. 1-(p-
Chlorophenyl)-1-propyne [21], 1-(m-chlorophenyl)-
1-propyne [21], 1-(p-tolyl)-1-propyne [22], 1-(p-
methoxyphenyl)-1-propyne [21], PhCHꢀC(OMe)Me
[23], and complexes [PdCl2(COD)] [24], [PtCl2(COD)]
[24], [PdCl2(PhSCH2CH2CH2SPh)] [25], [(Ph3P)(PhS)-
Pd(m-SPh)]2 [26], [IrCl(COD)]2 [27], [Cp*IrCl(m-
3.4. Preparation of
[(Cp*Ir)2(v3-S)2PdCl(PPh3)]Cl·CH2Cl2 (5·CH2Cl2)
Complex 2 (70 mg, 0.088 mmol) and [Pd(PPh3)4] (102
mg, 0.088 mmol) were dissolved in THF (15 ml), and
the mixture was stirred at r.t. for 48 h. The solvent was
removed under reduced pressure, and the residual solid
was extracted with CH2Cl2. Addition of benzene and
hexane to the concentrated extract gave [(Cp*Ir)2(m3-
S)2PdCl(PPh3)]Cl·CH2Cl2 (5·CH2Cl2) as dark brown
crystals (75 mg, 0.060 mmol, 68% yield). 1H-NMR
(CD3COCD3): l 2.09 (s, 30H, Cp*), 7.46–7.61 (m,
15H, Ph). 31P{1H}-NMR (CD3COCD3): l 28.2 (s).
Anal. Calc. for C39H47Cl4Ir2PPdS2: C, 37.67; H, 3.81.
Found: C, 37.63; H, 3.82%. In a separate run, the
gaseous phase was analyzed by GLC to reveal that H2
was formed in 47% yield based on the complex 2 used.
Cl)2IrCp*Cl]
[28],
[(Cp*Ru)2Pd2(m3-S)2(SiPr)(m-
SiPr)(PPh3)] [29], [Pd(PPh3)(m-S)2{W(S2CNEt2)}2(m-S)2]
[15], and [Pt(PPh3)(m-S)2{W(S2CNEt2)}2(m-S)2] [15] were
prepared by the literature methods. Solvents were dried
and distilled prior to use. Other reagents were commer-
cially obtained and used without further purification.
IR spectra were recorded on a Shimadzu 8100M spec-
trometer. 1H- and 13C{1H}-NMR spectra were obtained
on a JEOL JNM-LA 400 spectrometer (1H, 400 MHz;
13C, 101 MHz), and 31P{1H}-NMR spectra on a JEOL
EX-270 spectrometer (109 MHz). Quantitative GLC
analyses of liquid products were performed on a Shi-
madzu GC-14A instrument equipped with a flame ion-
ization detector using a 25 m×0.25 mm CBP10 fused
silica capillary column, while GLC analyses of gaseous
products were carried out on a Shimadzu GC-8A in-
strument equipped with a thermal conductivity detector
using a molecular sieve 13X column. Elemental analy-
ses were performed on a Perkin–Elmer 2400II CHN
analyzer. XPS analyses were carried out by using a
Kratos XSAM800pci spectrometer.
3.5. Reactions of clusters 3 and 4 with PPh3
To a CDCl3 solution (0.65 ml) of cluster 3 (0.015
mmol) in an NMR tube was added PPh3 (0.018 mmol)
to give a greenish brown solution. The 1H- and
31P{1H}-NMR spectra of the solution were essentially
identical to those of cluster 5 except that a small
amount of free PPh3 was also detected. Further addi-
tion of PPh3 (0.035 mmol) to this solution caused color
change to red brown. The 1H- and 31P{1H}-NMR
spectra indicated the formation of a new cluster species,
which is tentatively identified as [(Cp*Ir)2(m3-
S)2Pd(PPh3)2]Cl2 (6). The molar ratio of 5 and 6 in the
solution was determined to be 73:27 based on the
31P{1H}-NMR spectrum. Selected spectral data of 6 are
3.2. Preparation of [(Cp*Ir)2(v3-S)2PdCl2] (3)
To a solution of complex 2 (477 mg, 0.602 mmol)
in THF (20 ml) was added [PdCl2(COD)] (270
mg, 0.946 mmol), and the mixture was stirred at 50°C
for 15 h. The dark green solid that deposited was
collected by filtration and recrystallized from CH2Cl2–
hexane to afford [(Cp*Ir)2(m3-S)2PdCl2] (3) as dark
1
as follows. H-NMR (CDCl3): l 2.09 (s, 30H, Cp*).
31P{1H}-NMR (CDCl3): l 20.5 (s).
1
Similarly, the H- and 31P{1H}-NMR analysis of a
1
green crystals (399 mg, 0.445 mmol, 74% yield). H-
green CDCl3 solution containing cluster 4 (0.011 mmol)
and PPh3 (0.011 mmol) showed that ca. 80% of 4 was
converted to [(Cp*Ir)2(m3-S)2PtCl(PPh3)]Cl (7). 1H-
NMR (CDCl3): l 2.06 (s, 30H, Cp*). 31P{1H}-NMR
(CDCl3): l 12.7 (s, JPtꢁP=3945 Hz). Further addition
of PPh3 (0.010 mmol) to the above solution caused
rapid color change to purple, where [(Cp*Ir)2(m3-
S)2Pt(PPh3)2]Cl2 (8) was the only cluster species de-
tected by NMR. 1H-NMR (CDCl3): l 2.08 (s, 30H,
Cp*). 31P{1H}-NMR (CDCl3): l 2.9 (s, JPtꢁP=3685
Hz).
NMR (CDCl3): l 2.15 (s, 30H, Cp*). Anal. Calc. for
C20H30Cl2Ir2PdS2: C, 26.80; H, 3.37. Found: C, 26.35;
H, 3.47%.
3.3. Preparation of [(Cp*Ir)2(v3-S)2PtCl2] (4)
To a solution of complex 2 (60 mg, 0.076 mmol) in
THF (8 ml) was added [PtCl2(COD)] (34 mg, 0.091
mmol), and the mixture was stirred at 50°C for 15 h.
The dark green solid that deposited was collected by

76
D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
3.6. Preparation of [(Cp*Ir)2(v3-S)2Pt(PPh3)2][BPh4]2
(8’)
p-H of BPh4), 6.90 (t, 16H, J=7.1 Hz, m-H of BPh4),
7.29–7.36 (m, 16H, o-H of BPh4), 7.63–7.72 (m, 20H,
Ph of dppe). 31P{1H}-NMR (CD3COCD3): l 49.4 (s,
To a solution of 4 (35 mg, 0.036 mmol) in CH2Cl2 (4
ml) was added PPh3 (25 mg, 0.095 mmol). The mixture
immediately turned purple and was stirred at r.t. for 4
h. Then the solvent was removed in vacuo, NaBPh4 (32
mg, 0.094 mmol) and THF (4 ml) were added to the
residue, and the mixture was stirred for 15 h. The
solvent was evaporated to dryness, and the residual
solid was extracted with CH2Cl2. Addition of hexane to
the concentrated extract deposited 8% as purple needles
(51 mg, 0.025 mmol, 69% yield). 1H-NMR
(CD3COCD3): l 2.14 (s, 30H, Cp*), 6.74–7.56 (m,
70H, PPh3 and BPh4). 31P{1H}-NMR (CD3COCD3): l
JPtꢁP=3517 Hz). Anal. Calc. for C97H100B2Ir2OP2PtS2:
C, 57.99; H, 5.02. Found: C, 57.59; H, 5.24%.
3.9. Preparation of [(Cp*Ir)2(v3-S)2PtCl(CNtBu)][PF6]
(11)
To an acetone solution (5 ml) of complex 4 (50 mg,
0.051 mmol) was added CNtBu (6 ml, 0.05 mmol), and
the mixture was stirred for 2 h at r.t. KPF6 (10 mg,
0.054 mmol) was added to the solution, and the solu-
tion was stirred for further 30 min. The resultant green
solution was filtered and evaporated in vacuo, and the
residual solid was recrystallized from acetone–hexane
to give 11 as green needles (24 mg, 20 mmol, 40%
4.2 (s,
JPtꢁP=3684 Hz). Anal. Calc. for
C104H100B2Ir2P2PtS2: C, 60.14; H, 4.85. Found: C,
60.30; H, 4.84%.
1
yield). H-NMR (CD3COCD3): l 2.12 (s, 30H, Cp*),
t
1.49 (s, 9H, Bu). IR (KBr) w(CN) 2203 cm−1. Anal.
3.7. Preparation of [(Cp*Ir)2(v3-S)2Pd(dppe)][BPh4]2·
CH3COCH3 (9·CH3COCH3)
Calc. for C25H39ClF6Ir2NPPtS2: C, 25.50; H, 3.34; N,
1.19. Found: C, 25.89; H, 3.32; N, 1.40%.
To a freshly prepared solution of 3 (50 mg, 0.056
mmol) in CH2Cl2 (5 ml) was added dppe (27 mg, 0.068
mmol). The color of the solution rapidly changed to
dark purple. NaBPh4 (191 mg, 0.558 mmol) was added
to the mixture, and the solution was stirred for 20 h.
The resulting mixture was filtered, and the filtrate was
dried up in vacuo and dissolved in acetone. Addition of
hexane to the acetone solution afforded 9·CH3COCH3
as dark purple crystals (63 mg, 0.033 mmol, 59% yield).
1H-NMR (CD3COCD3): l 2.02 (s, 30H, Cp*), 2.94 (br
d, 4H, J=23.1 Hz, CH2 of dppe), 6.76 (t, 8H, J=7.3
Hz, p-H of BPh4), 6.91 (t, 16H, J=7.3 Hz, m-H of
BPh4), 7.29–7.36 (m, 16H, o-H of BPh4), 7.64–7.74 (m,
20H, Ph of dppe). 31P{1H}-NMR (CD3COCD3): l 64.7
(s). Anal. Calc. for C97H100B2Ir2OP2PdS2: C, 60.67; H,
5.25. Found: C, 60.50; H, 5.25%.
3.10. Catalytic addition of alcohols to alkynes
The following procedure for the addition of MeOH
to 1-phenyl-1-propyne is representative. 1-Phenyl-1-
propyne (1.67 mmol) and a catalytic amount of cluster
3 (56 mmol, S/C=30) were dissolved in MeOH (2 ml),
and the solution was stirred at 50°C for 48 h. Then,
NEt3 (0.1 ml) was added to the reaction mixture in
order to prevent hydrolysis of the products, and the
mixture was analyzed by GLC, which showed that
2,2-dimethoxy-1-phenylpropane
(12a)
and
1,1-
dimethoxy-1-phenylpropane (13a) were formed in the
ratio of 98:2. The mixture was evaporated under re-
duced pressure, and the residue was dissolved in ether
and passed through a silica gel column (eluent, ether).
A small amount of K2CO3 was added to the eluate, and
the solvent was removed under reduced pressure. Bulb-
to-bulb distillation of the residual oil gave a 98:2 mix-
ture of 12a and 13a as a colorless oil (88% yield). 12a.
1H-NMR: l 1.12 (s, 3H, Me), 2.90 (s, 2H, CH2), 3.24
(s, 6H, OMe), 7.16–7.24 (m, 5H, Ph). 13C{1H}-NMR: l
20.9, 42.7, 48.0, 101.6, 126.1, 127.8, 130.0, 137.3. 13a.
1H-NMR: l 0.58 (t, 3H, J=7.8 Hz, Me), 1.90 (q, 2H,
J=7.8 Hz, CH2), 3.12 (s, 6H, OMe). The aromatic
signals could not be assigned because of overlapping
with those of 12a.
3.8. Preparation of [(Cp*Ir)2(v3-S)2Pt(dppe)][BPh4]2·
CH3COCH3 (10·CH3COCH3)
To a freshly prepared solution of 4 (100 mg, 0.102
mmol) in CH2Cl2 (10 ml) was added dppe (49 mg, 0.123
mmol). The color of the solution rapidly changed to
dark purple. NaBPh4 (174 mg, 0.508 mmol) was added
to the mixture, and the solution was stirred for 20 h.
The resulting mixture was filtered, and the filtrate was
dried up in vacuo and dissolved in acetone. Addition of
hexane to the acetone solution precipitated dark purple
crystals of 10·CH3COCH3 and a small amount of
brown powder. The crystals of 10·CH3COCH3 were
collected by decantation, washed with hexane, and
Acetals 12b–h and 13b–h were obtained by similar
procedures. Selected spectral data are as follows.
3.10.1. 2,2-Diethoxy-1-phenylpropane (12b)
1H-NMR: l 1.15 (s, 3H, Me), 1.21 (t, 6H, J=7.3 Hz,
OCH2Me), 2.94 (s, 2H, CH2Ph), 3.55 (m, 4H, OCH2),
7.17–7.32 (m, 5H, Ph). 13C{1H}-NMR: l 15.4, 22.1,
43.8, 55.7, 101.5, 126.1, 127.8, 130.2, 137.7.
1
dried in vacuo (90 mg, 0.045 mmol, 44% yield). H-
NMR (CD3COCD3): l 2.03 (s, 30H, Cp*), 2.91 (br d,
4H, J=19.5 Hz, CH2 of dppe), 6.76 (t, 8H, J=7.1 Hz,

D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
77
3.10.2. 1,1-Diethoxy-1-phenylpropane (13b)
1H-NMR: l 0.57 (t, 3H, J=6.9 Hz, Me), 1.92 (q,
2H, J=6.9 Hz, CCH2Me). The ethoxy and aromatic
signals could not be assigned because of overlapping
with those of 12b.
3.10.11. 2,2-Dimethoxy-1-(p-tolyl)propane (12g)
1H-NMR: l 1.13 (s, 3H, Me), 2.30 (s, 3H, C6H4Me),
2.87 (s, 2H, CH2), 3.25 (s, 6H, OMe), 7.07 (d, 2H,
J=8.3 Hz, aryl), 7.12 (d, 2H, J=8.3 Hz, aryl).
13C{1H}-NMR: l 20.88, 20.94, 42.2, 48.1, 101.7, 128.6,
129.9, 134.2, 135.6.
3.10.3. 2,2-Dimethoxy-1-phenylbutane (12c)
1H-NMR: l 0.85 (t, 3H, J=7.6 Hz, Me), 1.46 (q,
2H, J=7.6 Hz, CH2Me), 2.90 (s, 2H, CH2Ph), 3.26 (s,
6H, OMe), 7.18–7.24 (m, 5H, Ph). 13C{1H}-NMR: l
7.9, 25.1, 37.7, 47.8, 103.9, 126.1, 128.0, 129.7, 136.9.
3.10.12. 2,2-Dimethoxy-1-(p-tolyl)propane (13g)
1H-NMR: l 0.59 (t, 3H, J=7.7 Hz, Me), 1.91 (q,
2H, J=7.7 Hz, CH2), 2.33 (s, 3H, C6H4Me), 3.14 (s,
6H, OMe). The aromatic signals could not be assigned
because of overlapping with those of 12g.
3.10.4. 1,1-Dimethoxy-1-phenylbutane (13c)
1H-NMR: l 1.00 (t, 3H, J=7.2 Hz, Me), 1.85
(pseudo t, 2H, J=7.7 Hz, CH2C(OMe)2), 3.13 (s, 6H,
OMe). The methylene and aromatic signals could not
be assigned because of overlapping with those of 12c.
3.10.13. 2,2-Dimethoxy-1-(p-methoxyphenyl)propane
(12h)
1H-NMR: l 1.12 (s, 3H, Me), 2.84 (s, 2H, CH2), 3.25
(s, 6H, C(OMe)2), 3.75 (s, 3H, C6H4OMe), 6.80 (d, 2H,
J=8.6 Hz, aryl), 7.13 (d, 2H, J=8.6 Hz, aryl).
13C{1H}-NMR:l 21.7, 42.5, 48.9, 55.8, 102.5, 114.1,
131.7, 133.4, 159.6.
3.10.5. 2,2-Dimethoxy-1-phenylhexane (12d)
1H-NMR: l 0.83 (t, 3H, J=6.9 Hz, Me), 1.18–1.39
(m, 6H, (CH2)3), 2.91 (s, 2H, CH2Ph), 3.27 (s, 6H,
OMe), 7.15–7.32 (m, 5H, Ph). 13C{1H}-NMR: l 13.9,
22.7, 25.7, 32.3, 38.3, 47.9, 103.6, 126.2, 128.1, 129.8,
137.3.
3.10.14. 1,1-Dimethoxy-1-(p-chlorophenyl)propane
(13h)
1H-NMR: l 0.58 (t, 3H, J=7.3 Hz, Me), 1.87 (q,
2H, J=7.3 Hz, CH2), 3.12 (s, 6H, C(OMe)2), 3.77 (s,
3H, C6H4OMe), 6.85 (d, 2H, J=8.9 Hz, aryl), 7.30 (d,
2H, J=8.9 Hz, aryl). 13C{1H}-NMR: l 8.4, 30.5, 49.1,
55.8, 104.7, 113.8, 128.9, 130.1, 159.7.
3.10.6. 1,1-Dimethoxy-1-phenylhexane (13d)
1H-NMR: l 0.95 (t, 3H, J=8.6 Hz, Me), 1.85
(pseudo t, 2H, J=8.3 Hz, CH2C(OMe)2), 3.15 (s, 6H,
OMe). The methylene and aromatic signals could not
be assigned because of overlapping with those of 12d.
3.11. X-ray crystallographic studies
Single crystals of 5·CH2Cl2, 9·CH3COCH3, and
10·CH3COCH3 were sealed in glass capillaries under an
argon atmosphere and used for data collection. Diffrac-
tion data were collected on a Rigaku AFC7R four-cir-
3.10.7. 2,2-Dimethoxy-1-(p-chlorophenyl)propane (12e)
1H-NMR: l 1.10 (s, 3H, Me), 2.86 (s, 2H, CH2), 3.24
(s, 6H, OMe), 7.15 (d, 2H, J=8.4 Hz, aryl), 7.22 (d,
2H, J=8.4 Hz, aryl). 13C{1H}-NMR: l 20.9, 42.1,
48.1, 101.3, 128.0, 131.4, 132.0, 135.8.
cle
automated
diffractometer
with
graphite-
,
monochromatized Mo–Ka radiation (u=0.71069 A) at
21°C using the ꢀ–2q scan technique for 5·CH2Cl2
3.10.8. 1,1-Dimethoxy-1-(p-chlorophenyl)propane (13e)
1H-NMR: l 0.56 (t, 3H, J=7.7 Hz, Me), 1.87 (q,
2H, J=7.7 Hz, CH2), 3.12 (s, 6H, OMe). The aromatic
signals could not be assigned because of overlapping
with those of 12e.
(5B2qB55°) and the
ꢀ
scan technique for
9·CH3COCH3 and 10·CH3COCH3 (5B2qB50°). In-
tensity data were corrected for Lorentz and polariza-
tion effects and for absorption (empirical, ꢀ scans). For
crystals of 5·CH2Cl2, no significant decay was observed
for three standard reflections monitored every 150
reflections during the data collection. For compounds
9·CH3COCH3 and 10·CH3COCH3, a slight decay
(9·CH3COCH3, 1.81%; 10·CH3COCH3, 6.57%) was ob-
served during the data collection, and a correction for
decay was applied in each case.
3.10.9. 2,2-Dimethoxy-1-(m-chlorophenyl)propane (12f)
1H-NMR: l 1.13 (s, 3H, Me), 2.88 (s, 2H, CH2), 3.25
(s, 6H, OMe), 7.10–7.24 (m, 4H, aryl). 13C{1H}-NMR:
l 21.0, 42.5, 48.3, 101.4, 126.4, 128.3, 129.2, 130.2,
133.7, 139.5.
The structure solution and refinements were carried
out by using the TEXSAN crystallographic software
package [30]. The positions of the non-hydrogen atoms
were determined by Patterson methods (DIRDIF
PATTY [31]) and subsequent Fourier syntheses. The
carbon atoms of the phenyl groups in the dppe ligands
of 10·CH3COCH3 were refined with isotropic thermal
3.10.10. 1,1-Dimethoxy-1-(m-chlorophenyl)propane
(13f)
1H-NMR: l 0.58 (t, 3H, J=7.2 Hz, Me), 1.88 (q,
2H, J=7.2 Hz, CH2), 3.15 (s, 6H, OMe). The aromatic
signals could not be assigned because of overlapping
with those of 12f.

78
D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
Table 5
X-ray crystallographic data for 5·CH2Cl2, 9·CH3COCH3, and 10·CH3COCH3
5·CH2Cl2
9·CH3COCH3
10·CH3COCH3
Formula
C39H47Cll4Ir2PPdS2
1243.55
Monoclinic
P21/m
C97H100B2Ir2OP2PdS2
1920.38
Monoclinic
P21/n
C97H100B2Ir2OP2PtS2
2009.07
Monoclinic
P21/n
Formula weight
Crystal system
Space group
Crystal size (mm)
0.40×0.40×0.15
12.021(2)
12.542(3)
14.667(2)
93.02(1)
2208.3(6)
2
68.29
0.50×0.40×0.30
14.725(4)
22.400(3)
26.877(3)
103.67(1)
8614(2)
0.40×0.25×0.20
14.754(3)
22.444(3)
26.854(3)
103.58(1)
8643(2)
,
a (A)
,
b (A)
,
c (A)
i (°)
3
,
V (A )
Z
4
4
m(Mo–Ka) (cm−1
)
34.29
48.20
Unique reflections
Observed reflections
Number of variables
5306 [Rint=0.031]
3572 (I\3|(I))
239
0.048
0.042
15103 [Rint=0.046]
7276 (I\3|(I))
929
0.045
0.027
15145 [Rint=0.045]
6604 (I\3|(I))
808
0.066
0.048
a
R
Rw
b
Goodness-of-fit c
2.63
1.54
1.93
a R=ꢀꢁꢁFoꢁ−ꢁFcꢁꢁ/ꢀꢁFoꢁ.
b Rw=[ꢀw(ꢁFoꢁ−ꢁFcꢁ)2/ꢀwF2o]1/2, w=[s2c(Fo)+p2F2o/4]−1
.
c GOF=[ꢀw(ꢁFoꢁ−ꢁFcꢁ)2/(Nobs−Nparams)]1/2
.
Acknowledgements
parameters, and fixed isotropic parameters were used
for the carbon and oxygen atoms of the acetone
molecules in 9·CH3COCH3 and 10·CH3COCH3. The
other non-hydrogen atoms were refined by full-matrix
least-squares techniques (based on F) with anisotropic
thermal parameters. Hydrogen atoms except for those
of the acetone molecules in 9·CH3COCH3 and
10·CH3COCH3 were placed at the calculated positions
This work was supported by a Grant-in-aid for Spe-
cially Promoted Research (09102004) from the Ministry
of Education, Science, Sports, and Culture, Japan.
References
,
(dCꢁH=0.95 A) and were included with fixed isotropic
[1] (a) R.D. Adams, F.A. Cotton (Eds.), Catalysis by Di and
Polynuclear Metal Cluster Complexes, Wiley, New York, 1998.
(b) G. Su¨ss-Fink, G. Meister, Adv. Organomet. Chem. 35 (1993)
41.
parameters. Reinvestigation of the crystal structure of
5·CH2Cl2, which is reported herein, gave slightly differ-
ent cell parameters from those described previously
[7b], but the molecular structure obtained was essen-
tially the same. Details of the X-ray diffraction study
are summarized in Table 5.
[2] (a) R.H. Holm, S. Ciurli, J.A. Weigel, Prog. Inorg. Chem. 38
(1990) 1. (b) B. Krebs, G. Henkel, Angew. Chem. Int. Ed. Engl.
30 (1991) 769. (c) T. Shibahara, Coord. Chem. Rev. 123 (1993)
73. (d) T. Saito, in: M.H. Chisholm (Ed.), Early Transition
Metal Clusters with p-Donor Ligands, VCH, New York, 1995,
chapter 3. (e) I. Dance, K. Fisher, Prog. Inorg. Chem. 41 (1994)
637. (f) P. Mathur, Adv. Organomet. Chem. 41 (1997) 243. (g)
H. Ogino, S. Inomata, H. Tobita, Chem. Rev. 98 (1998) 2093.
[3] (a) M. Rakowski DuBois, Chem. Rev. 89 (1989) 1. (b) J.C.
Bayo´n, C. Claver, A.M. Masdeu-Bulto´, Coord. Chem. Rev.
193–195 (1999) 73.
[4] (a) M. Hidai, Y. Mizobe, H. Matsuzaka, J. Organomet. Chem.
473 (1994) 1. (b) M. Hidai, Y. Mizobe, in: E.I. Stiefel, K.
Matsumoto (Eds.), Transition Metal Sulfur Chemistry: Biologi-
cal and Industrial Significance, ACS Symposium Series 653,
American Chemical Society, Washington, DC, 1996, p. 310. (c)
M. Hidai, S. Kuwata, Y. Mizobe, Acc. Chem. Res. 33 (2000) 46.
[5] (a) T. Ikada, S. Kuwata, Y. Mizobe, M. Hidai, Inorg. Chem. 38
(1999) 64. (b) T. Amemiya, S. Kuwata, M. Hidai, Chem. Com-
mun. (1999) 711. (c) T. Iwasa, H. Shimada, A. Takami, H.
Matsuzaka, Y. Ishii, M. Hidai, Inorg. Chem. 38 (1999) 2851. (d)
4. Supplementary material
Crystallographic data for this structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC no. 146339 (compound 5·CH2Cl2),
no. 146340 (compound 9·CH3COCH3), and no. 146341
(compound 10·CH3COCH3). Copies of this information
may be obtained free of charge from The Director,
CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK
(Fax. +44-1223-336-033, or e-mail: deposit@ccdc.cam.
ac.uk or http://www.ccdc.cam.ac.uk).

D. Masui et al. / Journal of Organometallic Chemistry 620 (2001) 69–79
79
S. Matsukawa, S. Kuwata, M. Hidai, Inorg. Chem. 39 (2000)
791.
[15] T. Ikada, S. Kuwata, Y. Mizobe, M. Hidai, Inorg. Chem. 37
(1998) 5793.
[6] (a) T. Murata, H. Gao, Y. Mizobe, F. Nakano, S. Motomura, T.
Tanase, S. Yano, M. Hidai, J. Am. Chem. Soc. 114 (1992) 8287.
(b) T. Murata, Y. Mizobe, H. Gao, Y. Ishii, T. Wakabayashi, F.
Nakano, T. Tanase, S. Yano, M. Hidai, I. Echizen, H.
Nanikawa, S. Motomura, J. Am. Chem. Soc. 116 (1994) 3389.
(c) T. Wakabayashi, Y. Ishii, T. Murata, Y. Mizobe, M. Hidai,
Tetrahedron Lett. 36 (1995) 5585. (d) T. Wakabayashi, Y. Ishii,
K. Ishikawa, M. Hidai, Angew. Chem. Int. Ed. Engl. 35 (1996)
2123.
[7] (a) K. Hashizume, Y. Mizobe, M. Hidai, Organometallics 15
(1996) 3303. (b) Z. Tang, Y. Nomura, Y. Ishii, Y. Mizobe, M.
Hidai, Organometallics 16 (1997) 151. (c) Z. Tang, Y. Nomura,
Y. Ishii, Y. Mizobe, M. Hidai, Inorg. Chim. Acta 267 (1998) 73.
[8] (a) S. Kuwata, M. Hidai, Chem. Lett. (1998) 885. (b) S. Ka-
bashima, S. Kuwata, M. Hidai, J. Am. Chem. Soc. 121 (1999)
7837.
[9] (a) S. Kuwata, M. Andou, K. Hashizume, Y. Mizobe, M. Hidai,
Organometallics 17 (1998) 3429. (b) Z. Tang, Y. Nomura, S.
Kuwata, Y. Ishii, Y. Mizobe, M. Hidai, Inorg. Chem. 37 (1998)
4909. (c) T. Kochi, Y. Nomura, Z. Tang, Y. Ishii, Y. Mizobe,
M. Hidai, J. Chem. Soc. Dalton Trans. (1999) 2575. (d) S.
Kabashima, S. Kuwata, K. Ueno, M. Shiro, M. Hidai, Angew.
Chem. Int. Ed. 39 (2000) 1128.
[10] D. Masui, Y. Ishii, M. Hidai, Chem. Lett. (1998) 717.
[11] (a) Y. Fukuda, K. Utimoto, J. Org. Chem. 56 (1991) 3729. (b)
J.H. Teles, S. Brode, M. Chabanas, Angew. Chem. Int. Ed. 37
(1998) 1415. (c) Y. Kataoka, O. Matsumoto, K. Tani,
Organometallics 15 (1996) 5246. (d) C. Gemel, G. Trimmel, C.
Slugovc, S. Kremel, K. Mereiter, R. Schmid, K. Kirchner,
Organometallics 15 (1996) 3998.
[16] C.S. Bahn, A. Tan, S. Harris, Inorg. Chem. 37 (1998) 2770.
[17] N.M. Boag, M. Green, J.L. Spencer, F.G.A. Stone, J. Chem.
Soc. Dalton Trans. (1980) 1220.
[18] M. Tokunaga, Y. Wakatsuki, Angew. Chem. Int. Ed. Engl. 37
(1998) 2867.
[19] C. Hahn, A. Vitagliano, F. Giordano, R. Taube, Organometal-
lics 17 (1998) 2060.
[20] (a) W.D. Harman, J.C. Dobson, H. Taube, J. Am. Chem. Soc.
111 (1989) 3061. (b) W. Hiscox, P.W. Jennings, Organometallics
9 (1990) 1997. (c) M.M. Taqui Khan, S.B. Halligudi, S. Shukla,
J. Mol. Catal. 58 (1990) 299. (d) J. Blum, H. Huminer, H. Alper,
J. Mol. Catal. 75 (1992) 153. (e) J.W. Hartman, W. Hiscox, P.W.
Jennings, J. Org. Chem. 58 (1993) 7613. (f) I.K. Meier, J.A.
Marsella, J. Mol. Catal. 78 (1993) 31. (g) J. Yadav, S.K. Das, S.
Sarkar, J. Am. Chem. Soc. 119 (1997) 4315.
[21] E.J. Corey, P.L. Fuchs, Tetrahedron Lett. 36 (1972) 3769.
[22] B. Floris, E. Tassoni, Organometallics 13 (1994) 4746.
[23] H.O. House, V. Kramar, J. Org. Chem. 28 (1963) 3362.
[24] D. Drew, J.R. Doyle, Inorg. Synth. 28 (1990) 346.
[25] F.R. Hartley, S.G. Murray, W. Levason, H.E. Soutter, C.A.
McAuliffe, Inorg. Chim. Acta 35 (1979) 265.
[26] R. Zanella, R. Ros, M. Graziani, Inorg. Chem. 12 (1973) 2736.
[27] J.L. Herde, J.C. Lambert, C.V. Senoff, Inorg. Synth. 15 (1974)
18.
[28] C. White, A. Yates, P.M. Maitlis, Inorg. Synth. 29 (1992) 228.
[29] S. Kuwata, Y. Mizobe, M. Hidai, J. Am. Chem. Soc. 115 (1993)
8499.
[30] TEXSAN: Crystal Structure Analysis Package, Molecular Struc-
ture Corp., The Woodlands, TX, 1985 and 1992.
[31] PATTY: P.T. Beurskens, G. Admiraal, G. Beurskens, W.P.
Bosman, S. Garcia-Granda, R.O. Gould, J.M.M. Smits, C.
Smykalla, The DIRDIF program system, Technical Report of the
Crystallography Laboratory, University of Nijmegen: Nijmegen,
The Netherlands, 1992.
[12] S. Kuwata, Y. Mizobe, M. Hidai, unpublished results.
[13] A.L. Balch, V.J. Catalano, Inorg. Chem. 31 (1992) 2569.
[14] D.M.P. Mingos, A.S. May, in: D.F. Shriver, H.D. Kaesz, R.D.
Adams (Eds.), The Chemistry of Metal Cluster Complexes,
VCH, New York, 1990.
.