Syntheses and structures of the heterometallic clusters [(Ph 3PAu)3Re(CO)4], [(Ph3PAu) 4Re(CO)4]+, [(Ph3PAu) 6AuRe2(CO)8]+, and [(Ph 3PAu)6Re(CO)3]+

Article abstract of DOI:10.1016/j.ica.2005.02.022

The reaction of [HRe₃(CO)₁₂]^2- with an excess of Ph₃PAuCl in CH₂Cl₂ yields [(Ph ₃PAu)₄Re(CO)₄]⁺ as the main product, which crystallizes as [(Ph₃PAu)₄Re(CO) ₄]PF₆·CH₂Cl₂ (1·CH₂Cl₂) after the addition of KPF ₆.The crystal structure determination reveals a trigonal bipyramidal Au₄Re cluster with the Re atom in equatorial position. If [(Ph ₃PAu)₄Re(CO)₄]⁺ is reacted with PPh₄Cl, a cation [Ph₃PAu]⁺ is eliminated as Ph₃PAuCl, and the neutral cluster [(Ph₃PAu) ₃Re(CO)₄] (2) is formed.It combines with excess [(Ph ₃PAu)₄Re(CO)₄]⁺ to afford the cluster cation, [(Ph₃PAu)₆AuRe₂(CO) ₈]⁺. It crystallizes from CH₂Cl₂ as[(Ph₃PAu)₆AuRe₂(CO)₈]PF ₆·4CH₂Cl₂ (3·4CH ₂Cl₂). In [(Ph₃PAu)₃Re(CO) ₄] the metal atoms are arranged in form of a lozenge while in [(Ph₃PAu)₆AuRe₂(CO)₈]⁺ two Au₄Re trigonal bipyramids are connected by a common axial Au atom. The treatment of [(Ph₃PAu)₄Re(CO)₄] ⁺ with KOH and Ph₃PAuCl in methanol yields the cluster cation [(Ph₃PAu)₆Re(CO)₃]⁺, which crystallizes with PF6- from CH₂Cl₂ as [(Ph ₃PAu)₆Re(CO)₃]PF₆·CH ₂Cl₂ (4·CH₂Cl₂). The metal atoms in this cluster form a pentagonal bipyramid with the Re atom in the axial position.

Full text of DOI:10.1016/j.ica.2005.02.022

Inorganica Chimica Acta 358 (2005) 4301–4306
www.elsevier.com/locate/ica
Syntheses and structures of the heterometallic
clusters [(Ph PAu) Re(CO) ],
3
3
4
+
+
[
(Ph PAu) Re(CO) ] , [(Ph PAu) AuRe (CO) ] , and
3 4 4 3 6 2 8
+
[
(Ph PAu) Re(CO) ]
3 6 3
G. Pivoriunas, M. Richter, J. Str a¨ hle *
Institut f u¨ r Anorganische Chemie, Universit a¨ t T u¨ bingen, Auf der Morgenstelle 18, D-72076 T u¨ bingen, Germany
Received 7 February 2005; accepted 22 February 2005
Available online 3 June 2005
Dedicated to Professor Hubert Schmidbaur.
Abstract
The reaction of [HRe (CO) ] with an excess of Ph PAuCl in CH Cl yields [(Ph PAu) Re(CO) ] as the main product, which
2ꢀ
+
3
12
3
2
2
3
4
4
crystallizes as [(Ph PAu) Re(CO) ]PF Æ CH Cl (1 Æ CH Cl ) after the addition of KPF .The crystal structure determination reveals
3
4
4
6
2
2
2
2
6
4
a trigonal bipyramidal Au Re cluster with the Re atom in equatorial position.
+
+
If [(Ph
3
PAu)
4
Re(CO)
(Ph PAu) Re(CO) ] (2) is formed. It combines with excess [(Ph PAu) Re(CO) ] to afford the cluster cation, [(Ph PAu) AuRe
4
]
4 3 3
is reacted with PPh Cl, a cation [Ph PAu] is eliminated as Ph PAuCl, and the neutral cluster
+
[
3
3
4
3
4
4
3
6
2
+
] . It crystallizes from CH
(
CO)
8
2
Cl
2
as [(Ph
atoms are arranged in form of a lozenge while in [(Ph
3
PAu)
6
AuRe
PAu)
2
(CO)
8
]PF
AuRe (CO)
6
Æ 4CH
Cl
2 2
(3 Æ 4CH
] two Au Re trigonal bipyramids are connected by a com-
2
Cl
2
). In [(Ph
3
PAu)
3
4
Re(CO) ] the metal
+
3
6
2
8
4
mon axial Au atom.
The treatment of [(Ph
+
+
] ,
3
PAu)
ꢀ
4
Re(CO)
Cl
4
]
with KOH and Ph
as [(Ph PAu) Re(CO)
3
PAuCl in methanol yields the cluster cation [(Ph
]PF Æ CH Cl (4 Æ CH Cl
3
PAu)
6
Re(CO)
3
which crystallizes with PF6 from CH
a pentagonal bipyramid with the Re atom in the axial position.
2
2
3
6
3
6
2
2
2
2
). The metal atoms in this cluster form
Ó 2005 Elsevier B.V. All rights reserved.
Keywords: Heterometallic gold rhenium clusters; Synthesis; Crystal structure
1
. Introduction
heteroatom in the form of a metal carbonyl or azido
complex is present during the photolysis [2]. For exam-
ple we have used this method to synthesize the Mn–Au
In our previous work we have shown that homome-
tallic gold clusters can be obtained by the photolytic
decomposition of the gold(I) azido complexes R PAuN
+
clusters [(Ph PAu) Mn(CO) ]
3
and [(Ph PAu) Mn
3 6
4
4
+
+
(CO) ] [3]. [(Ph PAu) Mn(CO) ] as well as [(Ph PAu)
3
3
3
3
3
6
3
3
[
1]. Furthermore, the photolyses of the gold(I) azido
Mn(CO) ] can also be obtained with better yields by the
4
complexes can also be used for the synthesis of hetero-
metallic gold cluster compounds, if a source for the
photolysis of [Ph PAuMn(CO) ] and Ph PAuN [4,5].
3
3
5
3
We now report the syntheses and structures of the
analogous heterometallic rhenium gold clusters
+
+
*
[(Ph PAu) Re(CO) ] , and [(Ph PAu) Re(CO) ] , which
3 4 4 3 6 3
Corresponding author. Tel.: +49 7071 2976102; fax: +49 7071
92436.
E-mail address: joachim.straehle@uni-tuebingen.de (J. Str a¨ hle).
2
ꢀ
have been obtained from [HRe (CO) ] and
Ph PAuCl, and from the reaction of [(Ph PAu) Re
2
0
3
12
3
3
4
020-1693/$ - see front matter Ó 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2005.02.022

4302
G. Pivoriunas et al. / Inorganica Chimica Acta 358 (2005) 4301–4306
+
CO)4] with KOH and Ph PAuCl, respectively.
(
under vacuum and then redissolved in CH Cl , and cov-
2 2
3
[
tion of [(Ph PAu) Re(CO) ] with PPh Cl. In addition
(Ph PAu) Re(CO) ] could be synthesized by the reac-
+
ered with a layer of Et O. After several days in darkness
2
3
3
4
at 0 °C orange crystals of [(Ph PAu) AuRe (CO) ]-
3
4
4
4
3
6
2
8
the condensation reaction of [(Ph PAu) Re(CO) ] with
3
Cl Æ 4CH Cl are formed as well as small amounts of
2 2
3
4
+
(Ph PAu) Re(CO) ] affords the cluster [(Ph PAu)
[
AuRe (CO) ] . [(Ph PAu) Re(CO) ]BF and [(Ph PAu) -
Ph PAuCl and [(Ph PAu) Re(CO) ]. The majority of
3 3 3 4
3
4
4
3
6
+
the latter compound remains in solution. It is isolated
after filtration and reduction of the solution under
vacuum. Single crystals of [(Ph PAu) Re(CO) ] can be
2
8
3
4
4
4
3
3
Re(CO) ] have already been obtained by the reaction
4
ꢀ
of [Re(CO)5] or Ph PAuRe(CO) with the oxonium
3
5
3
3
4
+
cation [(Ph PAu) O] [6]. Ellis et al. [7] synthesized
obtained from a CH Cl solution by covering it with a
2 2
3
3
3
ꢀ
[
(Ph PAu) Re(CO) ] from Ph PAuCl and [Re(CO) ]
4
.
layer of n-hexane. [(Ph PAu) Re(CO) ]: Anal. Calc. for
3 3 4
3
3
4
3
The crystal structures, however, have not been reported
by these authors. We had obtained [(Ph PAu) Re(CO) ]
C H Au O P Re: C, 41.56; H, 2.71. Found: C,
58 45 3 4 3
ꢀ1
+
42.94; H, 2.92%. IR (m/cm ): 1994, 1910 (CO). FAB -
3
3
4
2ꢀ
2
from the reaction of [(Ph PAu) ] with [HRe (CO) ]
+
+
+
,
MS: m/z = 1677.1 ([M] ); 1377.7 ([M ꢀ Re(CO) ] );
3
8
3
12
4
+
and solved the crystal structure [8].
1115.9 ([M ꢀ Re(CO) ꢀ PPh ] ). [(Ph PAu) AuRe
4
3
3
6
2
ꢀ
1
+
(
CO) ]Cl: IR (m/cm ): 1998, 1910 (CO). FAB -MS:
8
+ +
m/z = 3548.8 ([M] ); 3026.6 (M ꢀ Au ꢀ Re(CO) ꢀ CO] );
4
+
2
. Experimental
Ph PAuCl was prepared from tetrachloro gold acid
and PPh (Merck) in ethanol [9]. Re (CO) (Strem)
2969.1 ([M ꢀ 2PPh ꢀ 2CO] ); 2763.0 ([M ꢀ Au ꢀ
3
+
PPh ꢀ Re(CO) ꢀ CO] );
2706.0
([M ꢀ 3PPh ꢀ
3
4
3
+
+
2CO] ); 2499.9 ([M ꢀ Au ꢀ 2PPh ꢀ Re(CO) ꢀ CO] );
3
3
4
+
2238.9 ([M ꢀ Au ꢀ 3PPh ꢀ Re(CO) ꢀ CO] ); 2135.1
3
2
10
3
4
+
and K-Selectride, KB[CH(CH )C H ] H 1 mol/l in
2
([M ꢀ Au ꢀ 2Ph PAu ꢀ Re(CO) ] ); 1845.1 ([M ꢀ
3
5 3
3 4
+
THF (Aldrich) were purchased commercially. The sol-
vents used were dried and purified by the usual methods.
3Au ꢀ 3PPh ꢀ Re(CO) ꢀ CO] ); 1676.2 ([M ꢀ Au ꢀ
3 4
+
3Ph PAu ꢀ Re(CO) ] ); 1583.0 ([M ꢀ 3Au ꢀ 4PPh
3 4 3
+
ꢀ
Re(CO) ꢀ CO] ); 1377.0 ([M ꢀ Au ꢀ 3Ph PAu
4
4
3
+
2
.1. [(Ph PAu) Re(CO) ]PF (1)
6
ꢀ 2Re(CO) ] ).
3
4
4
To a solution of Re (CO) (330 mg, 0.51 mmol) in
2
10
2
.3. [(Ph PAu) Re(CO) ]PF (4)
3 6 3 6
15 ml THF 1.1 ml K-Selectride (1.1 mmol) is added.
After 3 h stirring the solution is cooled with liquid nitro-
KOH (50 mg, 0.9 mmol) dissolved in methanol is
added to mixture of [(Ph PAu) Re(CO) ]PF
6
gen. Now Ph PAuCl (650 mg, 1.31 mmol) dissolved in
3
a
3
4
4
1
5 ml THF is added in portions. The mixture is then al-
(500 mg, 0.22 mmol) and Ph PAuCl (217 mg,
3
lowed to return to room temperature. It is then briefly
stirred before the solvent is removed under vacuum.
The residue is dissolved in CH Cl and mixed with an
0
.44 mmol) dissolved in 80 ml methanol. The solution
is refluxed for 1 h. An orange red precipitate is formed
which is separated and dried in vacuum. The product
is redissolved in CH Cl and combined with KPF6.
After covering the solution with a layer of n-hexane or-
ange blocks of [(Ph PAu) Re(CO) ]PF Æ CH Cl crys-
2
2
excess of KPF . The mixture is now covered with a layer
6
2
2
of n-hexane and left for several days in the refrigerator.
The precipitate formed is separated and washed with
THF and dissolved again in CH Cl to remove the ex-
3
6
3
6
2
2
2
2
ꢀ1
tallize within a few days. Yield: 27%. IR (m/cm ):
1929, 1871 (CO), 838 (PF). FAB -MS: m/z = 3026.1
cess KPF . After filtration the solution is covered with
6
+
i
a layer of Pr O. Within one week yellow, light sensitive
2
+
+
+
(
2
[M] ); 2763.4 ([M ꢀ PPh ] ); 2501.3 ([M ꢀ 2PPh ] );
3
3
crystals of [(Ph PAu) Re(CO) ]PF Æ CH Cl
are
formed. Yield: (40%). Anal. Calc. for C H Au Cl -
3
4
4
6
2
2
+
+
239.5 ([M ꢀ 3PPh ] ); 1977.6 ([M ꢀ 4PPh ] ); 721.5
3
3
7
7
62
4
2
+
(
[M ꢀ Au ꢀ 4Ph PAu ꢀ Re(CO) ] );
459.0
([M ꢀ
3
3
F O P Re: C, 39.10; H, 2.64; F, 4.82. Found: C,
5
6
4
+
] ).
ꢀ
1
5Ph
3
PAu ꢀ Re(CO)
3
4
1
1
1
0.14; H, 1.82; F, 6.21%. IR (m/cm ): 2021, 1953,
+ +
929 (CO), 839 (PF). FAB -MS: m/z = 2135.1 (M );
+
+
845.1 ([M ꢀ PPh ꢀ CO] ); 1582.8 ([M ꢀ 2PPh ꢀ CO] );
2.4. X-ray structure determinations
3
3
+
115.2 ([M ꢀ 2PPh ꢀ Au ꢀ Re(CO) ] ).
3
4
The X-ray diffraction data were collected on a single
crystal diffractometer CAD4 with Mo Ka (1, 3b, 4) or
Cu Ka (2) radiation. The structures were solved by di-
rect methods using SHELXS-97 [10], and the refinement
was performed with SHELXL-97 [11]. The positions of
the H atoms were calculated for idealized positions
and refined using the riding model. Additional informa-
tion about the lattice constants and the refinement
parameters are given in Table 1.
2
AuRe (CO) ]Cl (3a)
.2. [(Ph PAu) Re(CO) ] (2) and [(Ph PAu)
3 3 4 3 6
2
8
[
PPh Cl (150 mg, 0.40 mmol) are dissolved in 25 ml
(Ph PAu) Re(CO) ]PF (180 mg, 0.08 mmol) and
3 4 4 6
4
CH Cl and stirred under reflux for 1 h. The solution
2
2
is then evaporated to dryness, and the residue is washed
with water to remove excess PPh Cl. The solid is dried
4

G. Pivoriunas et al. / Inorganica Chimica Acta 358 (2005) 4301–4306
4303
Table 1
Crystal data and parameters of the structure determination of [(Ph
3
PAu)
4
Re(CO) ]PF
4
6
Æ CH
2
Cl
2
, [(Ph
3
PAu)
3
Re(CO) ], [(Ph
4
3
PAu) AuRe
6
2
(CO)
8
]
PF
6
Æ 4CH
2
Cl
2
and [(Ph
3
PAu)
6
Re(CO)
(Ph
CH
3
]PF
6
Æ CH
2 2
Cl
[
3
PAu) Re(CO)
4
4
]PF
6
Æ
[(Ph
3
PAu)
3
Re(CO)
4
]
[(Ph
4CH
3
PAu) AuRe
6
2
(CO)
8
]PF
6
Æ
[(Ph
CH
3
PAu)
Cl
6
Re(CO) ]PF
3
6
Æ
2
Cl
2
2
Cl
2
2
2
Formula
C
77
H62Cl
2
F
6
4
O P
5
Au
4
Re
C
58
H
45
O
4
P
3
Au
3
Re
C
120
H
98Cl
8
F
6
O
8
P
7
Au
7
Re
2
C
112
H92Cl
2
F
6
3
O P
7
Au
6
Re
Molecular mass
Crystal system
Space group
2365.08
triclinic
1675.95
monoclinic
P2 /c
4033.54
triclinic
3255.54
monoclinic
P2 /c
ꢀ
ꢀ
P1
1
P1
1
Unit cell dimensions
˚
a (A)
˚
1197.1(2)
1714.4(2)
2030.9(4)
72.47(1)
72.85(2)
80.83(1)
1033.47(6)
3154.6(1)
3363.4(5)
90.0
1253.1(1)
1571.6(3)
1716.2(2)
84.72(1)
72.62(1)
73.41(1)
3091.0 Æ 10
1
2308.4(6)
1332.0(2)
3759.4(10)
90.0
b (A)
˚
c (A)
a (°)
b (°)
c (°)
98.30(1)
90.0
98.49(2)
90.0
3
6
6
6
6
Volume V (/m )
3786.6 Æ 10
2
2.074
10 850 Æ 10
8
2.052
11 432 Æ 10
4
Number of formula units Z
ꢀ
3
)
Density (g cm
2.167
10.547
1.891
8.925
ꢀ
1
Absorption coefficient (mm
Absorption correction
)
9.553
w-scans
0.5171/0.9820
Mo Ka
208
20.35
w-scans
0.8073/0.9755
w-scans
DIFABS [20]
0.136/0.607
Mo Ka
Tmin/Tmax
0.6993/0.9572
Mo Ka
208
Radiation
Cu Ka
213
Temperature of data
collection (K)
Measured reflections
223
14 556
13 333/0.0364
892
21 734
18 377/0.0363
1243
16 828
14 832/0.0396
715
23 539
22 478/0.0407
655
Independent reflections (Rint
Refined parameters
)
R values, R
Goodness-of-fit
CCDC deposit nos.
1
/wR
2
(I > 2r(I))
0.0439/0.0898
1.017
264 743
0.0437/0.0967
1.023
264 742
0.0472/0.0972
1.016
264 744
0.0669/0.1472
0.941
264 745
Standard deviations in brackets.
3
. Results and discussion
In our preceding work we had reacted the gold cluster
2
+
[(Ph PAu) ] with the reduction product of Re (CO)
3 8 2 10
to obtain the heterometallic cluster [(Ph PAu) Re(CO) ]
3
3
4
[
8]. The reduction of Re (CO) with two equivalents of
2 10
KB[CH(CH )C H ] H was assumed to yield K [Re
2
3
2
5 3
2
(
We have therefore tried to determine its structure, and
CO) ] [12]. Its structure was, however, not determined.
9
þ
crystallized it with PPh4 as counterion. The crystal
structure then revealed the cluster (PPh ) [HRe (CO) ]
4
2
3
12
[
13].
The reaction of this cluster, [HRe (CO) ]
2
ꢀ
with
Ph PAuCl afforded [(Ph PAu) Re(CO) ] as main prod-
3
+
12
3
3
4
4
ꢀ
+
uct. It can be crystallized with PF6 from a CH Cl solu-
2
3 4 4
Fig. 1. Structure of the cluster cation [(Ph PAu) Re(CO) ] [19].
2
tion as [(Ph PAu) Re(CO) ]PF Æ CH Cl in form of
3
4
4
6
2
2
Table 2
Selected interatomic distances [pm] in [(Ph
triclinic yellow blocks (Table 1). The crystal structure
determination shows that the metal atoms in the hetero-
metallic cluster cation form a trigonal bipyramid with
the Re atom in equatorial position (Fig. 1). This struc-
ture allows for approximately equal distances from the
Re atom to all four Au atoms. Two slightly shorter
bonds of 274.32(7) and 274.69(7) pm are formed to the
axial Au atoms. While the bond lengths to the equato-
rial Au atoms are 280.43(9) and 280.54(8) pm (Table
3
4 4 6
PAu) Re(CO) ]PF
Re–Au(1)
Re–Au(2)
Re–Au(3)
Re–Au(4)
274.3(1)
280.5(1)
280.4(1)
274.7(1)
Au(1)–Au(2)
Au(1)–Au(3)
Au(2)–Au(3)
Au(2)–Au(4)
Au(3)–Au(4)
292.9(1)
284.7(1)
279.4(1)
280.0(1)
297.9(1)
Standard deviations in brackets.
In preceding publications we have already shown that
the high stability of Ph PAuCl and its high tendency to
be formed can be used to degrade the heterometallic
2). The Au–Au distances are in the range of 279.38(7)
and 297.93(7) pm.
3

4304
G. Pivoriunas et al. / Inorganica Chimica Acta 358 (2005) 4301–4306
ꢀ
cluster cations with Cl to produce the neutral clusters
seems possible if a planar structure is formed. In this
case two bonding MOꢀs are formed. A M(CO) group
+
containing one less Ph PAu group. Cluster cations
3
3
undergoing this type of degradation are [(Ph PAu) Co
3
on the other hand has three frontier orbitals, one radial
and two tangential, which are arranged perpendicular to
one another. Their combination with the orbitals of the
4
+
+
(
ment with PPh Cl in CH Cl yield [(Ph PAu) Co(CO) ]
CO) ] and [(Ph PAu) Mn(CO) ] , which upon treat-
3 3 4 4
4
2
2
3
3
3
[
reaction to obtain [(Ph PAu) Re(CO) ] from the
14] and [(Ph PAu) Mn(CO) ] [5]. We have used this
Ph PAu groups to form three MOꢀs is optimized in a tet-
3
3
4
3
rahedral structure.
The crystal structure of [(Ph PAu) Re(CO) ] is built
3
3
4
+
cationic cluster [(Ph PAu) Re(CO) ] . [(Ph PAu) Au
3
4
4
3
6
3
3
4
+
Re (CO) ] is also formed as a byproduct of this reac-
up by two symmetrically independent molecules, which
do not show any significant structural differences. The
Re–Au distances are in the range of 271.0(1) and
274.1(1) pm, with the slightly shorter ones of 271.0(1)
or 271.4(1) pm to the central atoms Au(2) or Au(5) in
the two independent molecules (Table 3). The Au–Au
distances range from 277.6(1) to 282.4(1) pm.
2
8
tion. It is assumed to be the condensation product of
+
[
(Ph PAu) Re(CO) ] and [(Ph PAu) Re(CO) ] (Eq.
3 4 4 3 3 4
(
1)).
þ
[
(Ph PAu) Re(CO) ] + [(Ph PAu) Re(CO) ]
4
3
4
4
3
3
ð1Þ
þ
!
An analogous condensation reaction was assumed
[(Ph
3
PAu)
6
2 8 3
AuRe (CO) ] + PPh
For the crystal structure determination of the con-
densed cluster, the anion of the originally obtained
[(Ph PAu) AuRe (CO) ]Cl (3a) was exchanged with
to be the origin of the formation of [(Ph PAu) Au-
3
6
+
Co (CO) ] [14], which was originally obtained from
3
6
2
8
2
6
PF6ꢀ
(3b) to yield triclinic crystals with the composition
(Ph PAu) AuRe (CO) ]PF Æ 4CH Cl .
3 6 2 8 6 2 2
a photolysis reaction of Ph PAuN and Co (CO)
8
3
3
2
[
[
15].
Interestingly, two isomeric structures have been
found for clusters with an inner core Au M. If M is part
The inner core of the cluster [(Ph PAu) AuRe
2
3
6
+
(
CO) ] consists of two trigonal bipyramids Au Re con-
8
4
3
nected by one common axial Au atom to form a centro-
symmetrical structure (Fig. 3). In each trigonal
bipyramid the Re atom occupies an equatorial position
of a M(CO) group, then a tetrahedral structure as in
3
[
(Ph PAu) Co(CO) ] [14] is formed. With a M(CO)
3 3 3 4
group, however, a planar lozenge is present as was ob-
served in [(Ph PAu) M(CO) ] (M = Mn [5,7] and Re
+
as in the cluster [(Ph PAu) Re(CO) ] (Fig. 1).
4
3
4
3
3
4
The Re–Au distances have values between 274.8(1)
and 283.1(1) pm (Table 4). The longest distance corre-
sponds to the bond to the axial Au atom that connects
both trigonal bipyramids. While the shortest distance
is between the Re atom and the other axial Au atom.
The Au–Au distances are in a relatively large range from
(
orbitals of a M(CO) and M(CO) group is responsible
Fig. 2)). Obviously the different number of frontier
3
4
for the formation of different cluster structures [1,5]. A
M(CO) group has two frontier orbitals, one that points
4
to the center of the cluster and is called radial whereas
the other has a tangential orientation. In this case a bet-
ter overlap with the sp orbitals of the Ph PAu moieties
2
76.2(1) to 354.4(1) pm. The longest distance Au(1)–
3
Au(3) = 354.4(1) pm represents a very weak bonding
interaction.
+
With the examples of [(Ph PAu) Co(CO) ] and
3
6
2
2
+
[
the heterometallic gold clusters can be transformed with
(Ph PAu) Co(CO) ] [16] we had already shown that
3 7 2
+
Ph PAu into larger clusters if one of the CO ligands is
3
separated with the aid of the long known base reaction
ꢀ
with OH [17]. We have used this reaction to synthesize
+
+
[
(Ph PAu) Re(CO) ] from [(Ph PAu) Re(CO) ] (Eq.
3 6 3 3 4 4
(2)).
Table 3
Selected interatomic distances [pm] in the two symmetry independent
3 3 4
molecules [(Ph PAu) Re(CO) ]
Re(1)–Au(1)
Re(1)–Au(2)
Re(1)–Au(3)
Au(1)–Au(2)
Au(2)–Au(3)
272.9(1)
271.0(1)
274.1(1)
279.9(1)
277.6(1)
Re(2)–Au(4)
Re(2)–Au(5)
Re(2)–Au(6)
Au(4)–Au(5)
Au(5)–Au(6)
272.9(1)
271.4(1)
278.4(1)
282.4(1)
278.4(1)
Fig. 2. Structure of one of the two symmetry independent molecules
Standard deviations in brackets.
[
3 3 4
(Ph PAu) Re(CO) ] [19].

G. Pivoriunas et al. / Inorganica Chimica Acta 358 (2005) 4301–4306
4305
+
Fig. 3. Structure of the condensed cluster [(Ph
3
PAu) AuRe
6
2
(CO)
8
]
[19].
Table 4
Selected interatomic distances [pm] in [(Ph
3
6 2 8 6
PAu) AuRe (CO) ]PF
Re–Au(1)
Re–Au(2)
Re–Au(3)
Re–Au(4)
274.8(1)
277.4(1)
281.4(1)
283.1(1)
Au(1)–Au(2)
Au(1)–Au(3)
Au(2)–Au(3)
Au(2)–Au(4)
Au(3)–Au(4)
276.2(1)
354.4(1)
277.6(1)
296.0(1)
276.9(1)
Standard deviations in brackets.
þ
ꢀ
[
(Ph
3
PAu)
4
Re(CO)
4
] + 4 OH + 2Ph
þ
3
PAuCl
2ꢀ
ꢀ
!
[(Ph PAu)
3
6
Re(CO)
3
] + CO
3
2
+ 2 H O + 2Cl
ð2Þ
As in the case of the clusters with an inner core of
Au M the clusters Au M also show two different iso-
3
6
meric structures. As already mentioned a M(CO) group
3
like Mn(CO) or Re(CO) has three frontier orbitals,
3
3
+
one radial orbital that points to the center of the cluster
and two tangential orbitals. Since the tangential orbitals
are arranged perpendicular to one another the most
effective overlap with the orbitals of the Au atoms is
3 6 3
Fig. 4. Structure of the cluster cation [(Ph PAu) Re(CO) ] [19].
the Re atom in axial position. The Re–Au distances
are in a narrow range from 272.2(1) to 279.5(1) pm.
The shortest distance being between the Re atom to
the axial atom Au(6) (Table 5). The Au–Au distances
possible if the Au fragment has a hemispherical struc-
6
+
ture like in [(Ph PAu) Re(CO) ] (Fig. 4) and in
3
6
3
+
[
the bonding in [(Ph PAu) Re(CO) ] as well as in
(Ph PAu) Mn(CO) ] [4]. It is interesting to note that
3 6 3
+
3
6
3
+
(Ph PAu) Mn(CO) ] is similar to that in the cyclopen-
[
tadienyl complexes CpM(CO) (M = Mn, Re), since the
Table 5
Selected interatomic distances [pm] in [(Ph
3
6
3
3
PAu)
6
Re(CO)
3
]PF
6
3
hemispherical, pentagonal pyramidal unit (Ph PAu) in
3
Re–Au(1)
Re–Au(2)
Re–Au(3)
Re–Au(4)
Re–Au(5)
Re–Au(6)
Au(1)–Au(2)
Au(1)–Au(5)
276.0(1)
279.5(1)
272.2(1)
279.5(1)
273.5(1)
272.2(1)
284.3(1)
290.8(1)
Au(1)–Au(6)
Au(2)–Au(3)
Au(2)–Au(6)
Au(3)–Au(4)
Au(3)–Au(6)
Au(4)–Au(5)
Au(4)–Au(6)
Au(5)–Au(6)
290.3(1)
305.0(1)
282.0(1)
297.8(1)
294.0(1)
281.8(1)
281.9(1)
303.2(1)
6
these clusters behaves like a cyclopentadienyl ring.
When there is only one tangential frontier orbital, as
+
in the V(CO) group of [(Ph PAu) V(CO) ] [18], the
4
3
6
4
elliptical Au V structure observed obviously leads to a
6
better overlap.
The structure of the inner core Au Re in
6
+
(Ph PAu) Re(CO) ] is a pentagonal bipyramid with
[
Standard deviations in brackets.
3
6
3

4306
G. Pivoriunas et al. / Inorganica Chimica Acta 358 (2005) 4301–4306
on the other hand show a slightly larger variation be-
tween 281.8(1) and 305.0(1) pm.
[9] G. Brauer, Handbuch der Pr a¨ parativen Anorganischen Chemie,
Bd. 3, F., Enke Verlag, Stuttgart, 1981.
[
[
[
10] G.M. Sheldrick, SHELXS-97, A Program for the Solution of Crystal
Structures, University of G o¨ ttingen, 1997.
11] G.M. Sheldrick, SHELXL-97, A Program for the Refinement of
Crystal Structures, University of G o¨ ttingen, 1997.
12] W. Tam, M. Marsi, J.A. Gladysz, Inorg. Chem. 22 (1983) 1413.
References
[
1] J. Str a¨ hle, J. Organomet. Chem. 488 (1995) 15.
2] J. Str a¨ hle, in: P. Braunstein, L.A. Oro, P.R. Raithby (Eds.),
Metal Clusters in Chemistry, vol. 1, Wiley-VCH, Weinheim, 1999,
p. 535.
[13] M. Richter, Thesis, University of T u¨ bingen, 2004.
[14] G. Beuter, A. Brodbeck, M. Holzer, S. Maier, J. Str a¨ hle, Z.
Anorg. Allg. Chem. 616 (1992) 27.
[
[15] G. Beuter, J. Str a¨ hle, J. Organomet. Chem. 372 (1989) 67.
[16] M. Holzer, J. Str a¨ hle, G. Baum, D. Fenske, Z. Anorg. Allg.
Chem. 620 (1994) 192.
[
3] G. Beuter, J. Str a¨ hle, J. Less-Common. Met. 156 (1989) 387.
4] J. Mielcke, J. Str a¨ hle, Angew. Chem. Int. Ed. Engl. 31 (1992)
[
4
64.
[17] W. Hieber, F. Leutert, Z. Anorg. Allg. Chem. 204 (1932) 145.
[18] K. Wurst, J. Str a¨ hle, G. Beuter, D. Belli DellꢀAmico, F.
Calderazzo, Acta Chem. Scand. 45 (1991) 844.
[
5] M. Holzer, J. Str a¨ hle, Z. Anorg. Allg. Chem. 620 (1994) 786.
6] B.K. Nicholson, M.I. Bruce, O. bin Shawkataly, E.R.T. Tiekink,
J. Organomet. Chem. 440 (1992) 411.
[
[19] K. Brandenburg, DIAMOND, Information system for crystal
structures, Version 1.2, 1997.
[
[
7] J.E. Ellis, R.A. Faltynek, J. Am. Chem. Soc. 99 (1977) 1801.
8] M. Richter, D. Fenske, J. Str a¨ hle, Z. Naturforsch. 55b (2000)
[20] A.L. Spek, PLATON, A Program for the Calculation of Crystal-
lographic Data, University of Utrecht, 1996.
9
07.