A dinuclear phosphidoplatinum(II) fragment as a building block for tri-, tetra-, hexa-, and octanuclear complexes

Article abstract of DOI:10.1002/ejic.200500328

The dinuclear complex [(C₆F₅)₂Pt(μ- PPh₂)₂Pt(NCCH₃)₂] (1) is described and fully characterised. Complex 1 reacts with 2,2′-bipyrirnidine and cis-[M(C₆F₅)₂(THF)₂] to form the di-, tri- and tetranuclear complexes 2, 3 and 4, respectively, depending on the ratio of reagents and the type of metal (M = Pt, Pd). Complex 1 reacts with KCN to form the anionic dinuclear complex [PPh₃(CH₃)] ₂[(C₆F₅)₂Pt(μ-PPh ₂)₂Pt(CN)₂] (6). Complex 6 acts as a metalloligand towards cis-[M(C₆F₅)₂-(THF) ₂] or 1 to yield the corresponding hexanuclear or octanuclear complexes 7, 8 and 9. The structure of [PPh₃(CH₃)] ₄[{(C₆F₅)₂Pt(μ-PPh ₂)₂Pt(μ-CN)₂Pd(C₆F ₅)₂}₂] (8) has been established by X-ray diffraction. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.

Full text of DOI:10.1002/ejic.200500328

FULL PAPER
A Dinuclear Phosphidoplatinum(II) Fragment as a Building Block for Tri-,
Tetra-, Hexa-, and Octanuclear Complexes[‡]
Irene Ara,[a] Naima Chaouche,[a,b] Juan Forniés,*[a] Consuelo Fortuño,[a] Abdelaziz Kribii,[b]
and Antonio Martín[a]
Keywords: Bridging ligands / Cyanides / P ligands / Platinum / Self-assembly
The dinuclear complex [(C6F5)2Pt(µ-PPh2)2Pt(NCCH3)2] (1) is
described and fully characterised. Complex 1 reacts with
2,2Ј-bipyrimidine and cis-[M(C6F5)2(THF)2] to form the di-,
tri- and tetranuclear complexes 2, 3 and 4, respectively, de-
pending on the ratio of reagents and the type of metal (M =
Pt, Pd). Complex 1 reacts with KCN to form the anionic dinu-
clear complex [PPh3(CH3)]2[(C6F5)2Pt(µ-PPh2)2Pt(CN)2] (6).
Complex 6 acts as a metalloligand towards cis-[M(C6F5)2-
(THF)2] or 1 to yield the corresponding hexanuclear or octan-
uclear complexes 7,
8
and 9. The structure of
[PPh3(CH3)]4[{(C6F5)2Pt(µ-PPh2)2Pt(µ-CN)2Pd(C6F5)2}2]
(8)
has been established by X-ray diffraction.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2005)
dination chemistry towards different ligands with the aim
of establishing its synthetic potential as a building block for
species with predefined geometric shapes.
Introduction
The use of transition metal centres and coordination
chemistry for directing the formation of complex structures
has evolved into one of the most widely used strategies for
organizing molecular building blocks into supramolecular
arrays.[2–7] The directional-bonding approach, or “molecu-
lar library”, involves the assembly of large metal-containing
structures wherein the metal centres act as highly direc-
tional corner or side units in the resulting geometric shapes
or polyhedra. This approach uses a blocking ligand to pro-
tect coordination sites at the metal centre, thus controlling
the positions available for the binding of bridging ligands
and enabling the construction of the desired architecture.
This type of research began with the use of mononuclear
coordination centres, especially PdII and PtII,[8–10] but con-
siderable success has since been achieved by using dimetallic
entities instead.[11,12] In the course of our research in phos-
phido derivatives we have prepared several polynuclear
complexes that contain the “(C6F5)2Pt(µ-PPh2)2Pt” frag-
ment.[13–19] In some cases the precursor for this fragment
is the complex [(C6F5)2Pt(µ-PPh2)2Pt(S)2][20] (S = solvent)
which has been prepared in situ but never isolated. In this
paper we describe the isolation of the dinuclear derivative
[(C6F5)2Pt(µ-PPh2)2Pt(NCCH3)2] (1) and we study its coor-
Results and Discussion
The addition of AgClO4 to an acetone/acetonitrile solu-
tion of [Bu4N]2[{(C6F5)2Pt(µ-PPh2)2Pt(µ-Cl)}2] (molar ratio
2:1) results in the precipitation of silver chloride; [(C6F5)2-
Pt(µ-PPh2)2Pt(NCCH3)2] (1) is isolated as a white, stable
solid from the mother liquors. The 19F NMR spectrum
shows a signal with platinum satellites for the o-F atoms
and the resonances due to m- and p-F atoms (higher field)
appear overlapped, with the expected 2:3 intensity ratio
confirming the equivalence of both C6F5 groups. The 31P
NMR spectrum shows a signal (δ = –143.8 ppm) with plati-
num satellites for the two equivalent P atoms. The chemical
shift appears at high field, indicating that both PPh2 ligands
are supporting two metal centres not involved in M–M
1
bonds [3.443(1) Å]. Two values of JPt,P (1927 and 2454 Hz
for Pt1 and Pt2, respectively) can be calculated from the
platinum satellites (see Scheme 1 for atom numbering). The
assignment of each value to Pt1 or Pt2 can be carried out
considering the great trans influence of the C6F5 group and
comparing the values with those obtained in other similar
pentafluorophenyl derivatives.[21] The IR spectrum shows,
in the 800 cm–1 region, two absorptions of similar intensity
due to the X-sensitive mode of the C6F5 groups, in agree-
ment with the presence of the “cis-Pt(C6F5)2” frag-
ment,[22,23] and two absorptions in the 2300 cm–1 region due
to ν(CN) of the coordinated acetonitrile. All significant
spectroscopic data are given in the Exp. Sect.
[‡] Polynuclear Homo- or Heterometallic Palladium()-Plati-
num() Pentafluorophenyl Complexes Containing Bridging Di-
phenylphosphido Ligands, 17. Part 16: Ref.[1]
[a] Departamento de Química Inorgánica, Instituto de Ciencia de
Materiales de Aragón, Universidad de Zaragoza-C.S.I.C.,
50009 Zaragoza, Spain
Fax: +34-976-761-187
E-mail: juan.fornies@unizar.es
[b] Département de Chimie, Faculté des Sciences, Université Ibn
Tofail,
The crystal structure of complex 1 was determined by X-
ray diffraction and is shown in Figure 1. During the resolu-
B. P. 133, Kenitra, Morocco
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
DOI: 10.1002/ejic.200500328
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A Dinuclear Phosphidoplatinum() Fragment
FULL PAPER
Scheme 1.
tion of the structure, two essentially identical molecules of Table 1. Selected bond lengths [Å] and angles [°] for [(C6F5)2Pt(µ-
PPh2)2Pt(NCCH3)2]·Me2CO (1·Me2CO).
1 were found in the asymmetric part of the unit cell and we
will discuss only one of them now. Selected bond lengths
and angles are listed in Table 1. Complex 1 is a dinuclear
complex (Figure 1) in which the two Pt atoms are bridged
by two diphenylphosphido ligands. The square-planar envi-
ronments of the metal centres are completed by two cis-
pentafluorophenyl groups in the case of Pt(1), and two cis-
acetonitrile ligands in the case of Pt(2). The two acetonitrile
moieties are practically linear, as expected, and the bond
lengths and angles fall in the range usually found for this
ligand coordinated to Pt.[24–28] The molecular skeleton
C2PtP2PtN2 is not planar. The angle between the perpen-
dicular lines to the best square planes formed by the Pt
atoms and the atoms directly bonded to them is 33.94(4)°.
Pt(1)–C(1)
Pt(1)–P(2)
Pt(2)–P(2)
Pt(3)–C(47)
Pt(4)–N(4)
Pt(4)–P(4)
Pt(1)–P(1)
Pt(3)–C(41)
C(1)–Pt(1)–C(7)
C(7)–Pt(1)–P(1)
C(7)–Pt(1)–P(2)
N(1)–Pt(2)–N(2)
N(2)–Pt(2)–P(2)
N(2)–Pt(2)–P(1)
Pt(2)–P(1)–Pt(1)
C(41)–Pt(3)–
C(47)
2.061(5) Pt(1)–C(7)
2.2844(14) Pt(2)–N(1)
2.2641(14) Pt(2)–P(1)
2.070(5) Pt(3)–P(4)
2.083(5) Pt(4)–N(3)
2.2702(14) Pt(4)–P(3)
2.2820(14) Pt(2)–N(2)
2.070(5) Pt(3)–P(3)
2.065(5)
2.068(5)
2.2728(14)
2.2815(14)
2.087(5)
2.2566(14)
2.079(4)
2.2933(14)
98.01(15)
169.16(15)
75.36(5)
175.44(13)
100.08(13)
75.94(5)
98.40(5)
167.51(15)
92.6(2)
C(1)–Pt(1)–P(1)
167.61(15) C(1)–Pt(1)–P(2)
93.19(15) P(1)–Pt(1)–P(2)
87.54(18) N(1)–Pt(2)–P(2)
96.47(13) N(1)–Pt(2)–P(1)
172.36(13) P(2)–Pt(2)–P(1)
98.22(5) Pt(2)–P(2)–Pt(1)
92.77(19) C(41)–Pt(3)–
P(4)
C(47)–Pt(3)–P(4)
97.61(14) C(41)–Pt(3)–
P(3)
94.46(14)
C(47)–Pt(3)–P(3) 172.27(14) P(4)–Pt(3)–P(3)
74.88(5)
172.82(13)
97.29(13)
75.82(5)
N(4)–Pt(4)–N(3)
N(3)–Pt(4)–P(3)
N(3)–Pt(4)–P(4)
Pt(4)–P(3)–Pt(3)
88.36(18) N(4)–Pt(4)–P(3)
98.47(13) N(4)–Pt(4)–P(4)
174.06(13) P(3)–Pt(4)–P(4)
100.13(6) Pt(4)–P(4)–Pt(3)
100.07(5)
The well-known stability of Pt–C6F5 bonds and the Pt(µ-
PPh2)2Pt skeleton, and the lability of the Pt–N (acetonitrile)
bonds, make complex 1 an excellent dinuclear starting ma-
terial with a 90° angle between the “open-coordination
sites”.
Reaction of 1 with 2,2Ј-Bipyrimidine
In order to explore the potential of complex 1 as a pre-
cursor for self-assembly chemistry, we started the study by
Figure 1. Structure of the complex [(C6F5)2Pt(µ-PPh2)2Pt-
(NCCH3)2] (1).
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substituting the two acetonitrile ligands in 1 with 2,2Ј-bi- Reaction of 1 with Cyanide
pyrimidine (bpym), a ligand with four N donor atoms that
can be used as a linker of the building blocks.[29–32] Ad-
The cyanide ligand can act as a linear linker in polynu-
dition of bpym to an acetone solution of 1 in a 1:2 molar clear systems that exhibit fascinating structures and proper-
ratio (see Scheme 1) gave the linear tetranuclear complex ties.[35–41] Although the design of molecular entities has pro-
[(C6F5)2Pt(µ-PPh2)2Pt(µ-bpym)Pt(µ-PPh2)2Pt(C6F5)2] (2). duced large rings, stars, boxes, cages and clusters involving
This process is facilitated by both the sp2 hybridisation at cyanide bridging ligands, only a few examples with plati-
the N atoms, the chelate effect of the ligand and the high num centres in their structure have been reported.[42–47]
insolubility of 2. Nevertheless, when the ligand is added in With the aim of synthesising other homo- or heteronuclear
a 1:1 molar ratio the dinuclear complex [(C6F5)2Pt(µ- square molecules we decided to use the cyanide ligand as:
PPh2)2Pt(bpym)] (3) is obtained. The bpym ligand in 3 is a) it can easily act as a terminal ligand, thus allowing a
coordinated in a terminal chelating mode, and thus the designed synthesis through a two-pot process; b) although
other two N atoms can be used for further coordination. some bent cyanide bridges are known,[48] this group is usu-
Complex 2 can be obtained by the addition of 1 to solutions ally rigid and linear when acting as a bridging ligand; and
of 3 in acetone (1:1 molar ratio).
c) their anionic nature allows the synthesis of anionic mol-
With the aim of synthesising asymmetric derivatives we ecular squares. Although we have recently reported some
added cis-[M(C6F5)2(THF)2] (M = Pt, Pd) to CH2Cl2 solu- examples of anionic heterometallic squares,[42] these mole-
tions of 3 (1:1 molar ratio); the results are different for M cules are usually neutral or cationic with a high charge.
= Pt or Pd. In the first case the two donor N atoms of 3
The addition of KCN to acetone solutions of 1 in a 2:1
coordinate to the added platinum centre and the asymmet- molar ratio (a methyltriphenylphosphonium salt was also
ric, linear, trinuclear derivative [(C6F5)2Pt(µ-PPh2)2Pt(µ- added to facilitate the crystallisation) yielded the dinuclear
bpym)Pt(C6F5)2] (4a) crystallises from the solution. How- complex [PPh3(CH3)]2[(C6F5)2Pt(µ-PPh2)2Pt(CN)2] (6) in
ever, the reaction of 3 with cis-[Pd(C6F5)2(THF)2] does not which the cyanide groups act as terminal ligands. The two
yield the heteronuclear complex [(C6F5)2Pt(µ-PPh2)2Pt(µ- N atoms of 6 are bonded to other cis-blocked metal centres
bpym)Pd(C6F5)2] (4b) but rather
a
mixture of
2
to form the expected squares. The reaction of cis-
and [(C6F5)2Pd(µ-bpym)(C6F5)2] (5),[33] which were iden- [M(C6F5)2(THF)2] (M = Pt, Pd) with CH2Cl2 solutions of
tified by IR spectroscopy. The two complexes can be easily the metalloligand 6 (1:1 molar ratio) gave the hexanuclear
separated from this solid by dissolving 5 in acetone. The 1H anionic macrocycles [PPh3(CH3)]4[{(C6F5)2Pt(µ-PPh2)2-
NMR spectra of 3 and 4a show, in addition to PPh2 groups, Pt(µ-CN)2M(C6F5)2}2] (M = Pt, 7; Pd, 8). Similarly, the re-
three resonances due to the H4, H5 and H6 atoms of the action of 6 and 1 (1:1 molar ratio) afforded the octanuclear
bpym ligand, as expected for these asymmetric compounds. complex [PPh3(CH3)]4[{(C6F5)2Pt(µ-PPh2)2Pt(µ-CN)Pt(µ-
The 19F NMR spectra of 3 shows three signals (2 o-F, 2 m- PPh2)2Pt(C6F5)2}2] (9; Scheme 1). The 19F NMR spectrum
F, p-F) due to the equivalence of both C6F5 groups, while of 6 shows three signals in a 2:2:1 intensity ratio and the
complex 4a shows, as expected, the signals due to both low-field signal, due to the o-F atoms, shows platinum satel-
types of inequivalent C6F5 groups (see Exp. Sect.). The 31P lites. This is the expected pattern for 6 in which both C6F5
NMR spectra of 3 and 4a show the same pattern as 1.
groups are equivalent. In agreement with the formulation
In the IR spectra of complexes 2 and 3 two absorptions given in Scheme 1, the 19F NMR spectrum of 7 exhibits
of the same intensity due to the X-sensitive mode of the two signals in the o-F region (2:2 intensity ratio), two high-
C6F5 groups are observed in the 800 cm–1 region, in agree- field multiplets for the m-F (2:2 intensity ratio) and two
ment with the presence of the “cis-M(C6F5)2” frag- different signals for the p-F atoms (1:1 intensity ratio), thus
ment.[22,23] For complex 4a four absorptions due to the two confirming the presence of two non-equivalent C6F5 rings
different “cis-M(C6F5)2” fragments are observed. In ad- (C6F5 trans to CN and C6F5 trans to P). The spectrum of
dition, two intense sharp peaks of nearly equal intensity at 8 is analogous, but one m-F signal appears overlapped with
approximately 1580 and 1560 cm–1 (ring stretching modes that of the p-F one. Moreover, only one signal, with plati-
of bpym) characterise the terminal-chelating mode of the num satellites, is observed for the two types of o-F atoms
bpym ligand in complex 3. The presence of the bis(chelat- (C6F5 bonded to platinum or to palladium), thereby indi-
ing) mode (complexes 2, 4a and 5), however, is indicated cating that they are isochronous. This was unambiguously
either by an asymmetric doublet or a single strong broad confirmed by considering the intensity ratio of the platinum
feature in the same range.[34]
satellites and the central signal (1:10:1). For complex 9, the
All our attempts to obtain a single crystal of the tetra- two different o-F atoms are isochronous and the signals due
nuclear complex 2 suitable for X-ray diffraction purposes to m-F atoms are overlapped. Nevertheless, the presence of
failed, probably due to its insolubility. Although we ob- two inequivalent C6F5 groups is unambiguously demon-
tained single crystals of the asymmetric complex 4a and strated by the two well-separated p-F signals (see Exp.
collected data for two different crystals, in both cases the Sect.). The 31P NMR spectrum of 6 shows one high-field
value of R was not satisfactory, thus the structure of 4a signal with platinum satellites (1:8:17:8:1 intensity ratio) for
cannot be fully described. However, the skeleton of the the P atoms of the diphenylphosphido groups. The two
molecule and the connectivity of the atoms are as ex- doublets expected for the two isotopomers in which one
pected.
platinum centre is 195Pt (22.3% abundance each one) are
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A Dinuclear Phosphidoplatinum() Fragment
FULL PAPER
overlapped, ;indicating equal coupling constants between at δ = –157.9 ppm; this signal can be assigned to the P
the equivalent P atoms and the inequivalent Pt1 and Pt2 atoms of the “Pt3(µ-PPh2)2Pt4” fragment. The assignment
1
centres. This is in agreement with the easily observed signals of both JPt,P values (see Exp. Sect.) was carried out by
due to the isotopomer in which the two metal centres are comparison with the corresponding values observed in 1, 3
195Pt (11.3% abundance). The same spectral pattern is ob- and 4a.
served for complexes 7 and 8, thus indicating that the coor-
The relevant feature of the IR spectra of 6–9 is the pres-
dination of the N atoms of the CN ligand in 6 to the metal ence of two sharp absorptions at 2122 and 2113 cm–1 in 6
centre of the “cis-M(C6F5)2” fragment (M = Pt, Pd) does (terminal cyanide), which are assigned to ν(CϵN), and
not perceptibly change the magnetic environment of the Pt1 their significant shift towards higher frequencies in the
and Pt2 centres. The octanuclear macrocycle 9 shows two squares 7, 8 and 9 (bridging cyanide).[49] In all cases the
different types of diphenylphosphido ligands: the PPh2 absorptions observed in the 800 cm–1 region indicate the
groups bridging Pt1 and Pt2 centres, both with two Pt–C presence of “cis-M(C6F5)2” fragments.[22,23]
bonds (fragment from 6), and the PPh2 groups bridging Pt3
Figure 2a shows the structure of the anion in complex 8.
and Pt4 centres, with two Pt3–C and two Pt4–N bonds (frag- Selected bond lengths and angles are given in Table 2. The
ment from 1). The 31P NMR spectrum of 9 exhibits, in the X-ray structure establishes the presence of the hexanuclear
high-field region, two signals with platinum satellites. The complex anion [{(C6F5)2Pt(µ-PPh2)2Pt(µ-CN)2Pd(C6F5)2}2]4–
signal at δ = –161.0 ppm shows a pattern similar to the one and four [PPh3(CH3)]+ cations along with three molecules
observed for 6–8 and can be assigned to the P atoms of the of acetone and one molecule of n-hexane as lattice solvent.
“Pt1(µ-PPh2)2Pt2” fragment, while two different values of The platinum atoms are bonded to two diphenylphosphido
1JPt,P (1899 and 2400 Hz) can be extracted from the signal ligands, which act as bridges between both metal centres,
and to two C6F5 ligands in the case of Pt(2) or to two CN
bridging ligands in the case of Pt(1). The N atoms of the
cyanide are coordinated to the Pd atoms, which complete
their coordination with two C6F5 groups in cis positions.
The distances and angles in each coordination sphere are
within the expected values. The maximum deviation of the
metal atoms with respect to their best least-squares plane is
0.046 Å in the case of Pt(2). The C6F5 rings are essentially
perpendicular to their coordination planes, with angles
ranging from 77.0 to 91.4°. The coordination planes of
Pt(1) and Pd(1) are essentially coplanar (4.8°), while the
coordination plane of Pt(2) forms an angle of 22.1° with
that of Pt(1). The Pt(1) and Pd(1) atoms form an almost
perfect square, with edges of 5.19 and 5.21 Å, in which the
CN ligands are located, defining an open cavity which is
not large enough to accommodate the bulky cations or sol-
vent molecules (see Figure 2b).
Table 2. Selected bond lengths [Å] and angles [°] for {(PPh3Me)2-
[(C6F5)2Pt(µ-PPh2)2Pt(µ-CN)2Pd(C6F5)2]}2·3Me2CO·n-hexane
(8·3Me2CO·n-hexane).
Pt(1)–C(2)
Pt(1)–C(1)
Pt(1)–P(1)
Pt(1)–P(2)
Pt(2)–C(27)
Pt(2)–C(33)
Pt(2)–P(1)
C(2)–Pt(1)–C(1)
C(2)–Pt(1)–P(1)
C(1)–Pt(1)–P(1)
C(2)–Pt(1)–P(2)
C(1)–Pt(1)–P(2)
P(1)–Pt(1)–P(2)
C(27)–Pt(2)–C(33)
C(27)–Pt(2)–P(1)
C(33)–Pt(2)–P(1)
C(27)–Pt(2)–P(2)
1.999(5) Pt(2)–P(2)
2.016(5) Pd(1)–C(39)
2.3105(14) Pd(1)–C(45)
2.3198(13) Pd(1)–N(2)
2.064(5) Pd(1)–N(1)
2.069(5) N(1)–C(1)
2.2944(13) N(2)–C(2Ј)[a]
2.3111(14)
1.990(5)
1.993(5)
2.045(4)
2.045(5)
1.149(7)
1.149(6)
99.66(14)
76.30(5)
88.1(2)
91.42(18)
177.69(19)
177.5(2)
90.99(18)
89.57(16)
101.85(5)
101.06(5)
91.5(2)
C(33)–Pt(2)–P(2)
95.34(14) P(1)–Pt(2)–P(2)
172.75(14) C(39)–Pd(1)–C(45)
171.14(14) C(39)–Pd(1)–N(2)
97.32(14) C(45)–Pd(1)–N(2)
75.82(5) C(39)–Pd(1)–N(1)
90.78(19) C(45)–Pd(1)–N(1)
93.16(14) N(2)–Pd(1)–N(1)
175.78(14) Pt(2)–P(1)–Pt(1)
168.51(14) Pt(2)–P(2)–Pt(1)
Figure 2. a) Structure of the anion of [PPh3Me]4[{(C6F5)2Pt(µ-
PPh2)2Pt(µ-CN)2Pd(C6F5)2}2] (8). b) Packing diagram of the
anions in 8, showing how the cores of the molecular squares stack
to form an infinite tunnel.
[a] Symmetry transformation used to generate the equivalent atom
C(2Ј): –x + 1, –y + 1, –z + 1.
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used to prepare the starting materials [Bu4N]2[{(C6F5)2Pt(µ-PPh2)2-
Pt(µ-Cl)}2][21] and cis-[M(C6F5)2(THF)2] (M = Pt, Pd).[50]
We also tried to obtain an X-ray structure of complex 9
but unfortunately only poor quality crystals were obtained
after many crystallisation attempts. The X-ray data mea- Caution! Perchlorate salts of metal complexes with organic ligands
are potentially explosive. Only small amounts of material should be
prepared, and these should be handled with great caution.
sured with the diffractometer had a very low intensity,
which was almost non-existent at 2θ angles Ͼ 40°. Thus,
only a set of poor quality data could be obtained and there- Preparation of [(C6F5)2Pt(µ-PPh2)2Pt(NCCH3)2] (1): AgClO4
(0.150 g, 0.723 mmol) was added to
a solution of [Bu4N]2-
fore only the connectivity of the complex was established.
The skeleton is rather different to that of 8 since the central
core is not planar but angular, as schematized in Figure 3.
[{(C6F5)2Pt(µ-PPh2)2Pt(µ-Cl)}2] (1.000 g, 0.364 mmol) in acetone
(10 mL) and acetonitrile (10 mL). The mixture was stirred at room
temperature for 4 h, filtered, and the resulting solution was concen-
trated to ca. 5 mL, whereupon 1 crystallised as a white solid. iPrOH
(5 mL) was added and the mixture was stirred for 1 h. Complex 1
was collected by filtration and washed with 2 mL of iPrOH. Yield:
0.651 g (76%). C40H26F10N2P2Pt2 (1176.8): calcd. C 40.82, H 2.22,
N 2.38; found C 40.98, H 2.03, N 2.59. IR (nujol mull): ν = 782
˜
and 774 (X-sensitive C6F5 group),[22,23] 2323, 2294 (NϵC) cm–1.
19F NMR (282.4 MHz, [D6]acetone, 22°C): δ = –166.0 (6 m- + p-
F), –114.7 (3JPt,F
= 301 Hz, 4
o-F) ppm. 31P{1H} NMR
(121.5 MHz, [D6]acetone, 22°C): δ = –143.8 (JPt1,P = 1927, JPt2,P
=
2454 Hz) ppm.
Preparation of [(C6F5)2Pt(µ-PPh2)2Pt(µ-bpym)Pt(µ-PPh2)2Pt-
(C6F5)2] (2): 2,2Ј-bpym (0.013 g, 0.084 mmol) was added, with stir-
ring, to a colourless solution of 1 (0.200 g, 0.169 mmol) in acetone
(15 mL) and 2 began to precipitate as a yellow solid. After 45 min
stirring, 2 was filtered off, washed with 1 mL of acetone and vac-
uum-dried. Yield: 0.161 g (81%). C80H46F20N4P4Pt4 (2347.6):
calcd. C 41.00, H 1.97, N 2.38; found C 41.49, H 1.84, N 2.17. IR
Figure 3. Structure of the anion of [PPh3Me]4[{(C6F5)2Pt(µ-PPh2)2-
Pt(µ-CN)2Pt(µ-PPh2)2Pt(C6F5)2}2] (9).
(nujol mull): ν = 784, 776 (X-sensitive C F group), 1581 (bpym)
˜
6
5
cm–1. Complex 2 is not soluble enough in usual organic solvents
for NMR studies.
Preparation of [(C6F5)2Pt(µ-PPh2)2Pt(bpym)] (3): 2,2Ј-bpym
(0.013 g, 0.084 mmol) was added to a colourless solution of 1
(0.100 g, 0.084 mmol) in acetone (15 mL). After 15 h of stirring at
room temperature, the orange solution was concentrated almost to
dryness and CHCl3 (3 mL) was added while stirring. Complex 3
crystallised as a yellow solid, which was filtered off and washed
with 1 mL of CHCl3. Yield: 0.085 g (81%). C44H26F10N4P2Pt2
(1252.9): calcd. C 42.14, H 2.07, N 4.47; found C 41.74, H 1.85, N
Conclusion
Complex 1, in which the two acetonitrile ligands can be
easily replaced, can be considered as a neutral dinuclear
building block with “open-coordination sites” at 90°. The
study involves the design of one-dimensional complexes
with both diphenylphosphido and bpym ligands and two-
dimensional molecules with diphenylphosphido and cya-
nide ligands. The anionic dinuclear complex 6 is used as
a metalloligand towards neutral mononuclear or dinuclear
species. This is a straightforward route for the preparation
of homo- or heterometallic species. The choice of neutral
entities,“(C6F5)2Pt(µ-PPh2)2Pt” and “M(C6F5)2”, and an
anionic linker, cyanide, allowed us to synthesize the tetra-
anionic squares 7, 8 and 9, even though the complexes with
this molecular architecture that have been reported so far
are usually cationic or neutral species.
4.16. IR (nujol mull): ν = 783, 775 (X-sensitive C F group), 1580,
˜
6
5
1556 (bpym) cm–1. 1H NMR (300 MHz, [D6]acetone, 22°C): δ =
7.68 (t, JH5,H4,6 = 5.2 Hz, 2 H5-bpym), 8.36 (br. d, 2 H6-bpym), 9.32
(br. d, 2 H4-bpym) ppm. 19F NMR (282.4 MHz, [D6]acetone,
22°C): δ = –166.1 (2 p-F), –165.9 (4 m-F), –114.2 (3JPt,F = 301 Hz,
4 o-F) ppm. 31P{1H} NMR (121.5 MHz, [D6]acetone, 22°C): δ =
–125.6 (JPt1,P = 1859, JPt2,P = 2390 Hz) ppm.
Preparation of [(C6F5)2Pt(µ-PPh2)2Pt(µ-bpym)Pt(C6F5)2] (4a): cis-
[Pt(C6F5)2 (THF)2] (0.053 g, 0.078 mmol) was added to a yellow
solution of 3 (0.100 g, 0.079 mmol) in CH2Cl2 (10 mL). The colour
of the solution changed to brown, while a solid began to crystallise.
After 15 min of stirring, the brown solid 4a was filtered off and
washed with 1 mL of CH2Cl2. Yield: 0.071 g (50%).
C56H26F20N4P2Pt3 (1782.1): calcd. C 37.70, H 1.45, N 3.10; found
C 37.90, H 1.47, N 2.74. IR (nujol mull): ν = 816, 808, 782, 774
˜
Experimental Section
1
(X-sensitive C6F5 group), 1585 (bpym) cm–1. H NMR (300 MHz,
[D6]acetone, 22°C): δ = 8.00 (t, JH5,H4,6 = 5.4 Hz, 2 H5-bpym), 8.58
(br. d, 2 H6/4-bpym), 9.08 (br. d, 2 H4/6-bpym) ppm. 19F NMR
(282.4 MHz, [D6]acetone, 22°C): δ = –168.0 (6 m + p-F), –166.0 (4
m-F), –163.5 (2 p-F), –120.1 (3JPt,F = 459 Hz, 4 o-F), –116.0 (3JPt,F
= 300 Hz, 4 o-F) ppm. 31P{1H} NMR (121.5 MHz, [D6]acetone,
22°C): δ = –128.6 (JPt1,P = 1868, JPt2,P = 2414 Hz) ppm.
General Procedures: C, H and N analysis was performed with a
Perkin–Elmer 240B microanalyser. IR spectra were recorded with
a Perkin–Elmer Spectrum One spectrophotometer (Nujol mulls be-
tween polyethylene plates in the range 4000–350 cm–1). NMR spec-
tra were recorded with a Varian Unity 300 instrument with SiMe4,
1
CFCl3 and 85% H3PO4 as external references for H, 19F and 31P,
respectively. Conductivities (acetone, c Ϸ 5×10–4 ) were measured
with a Philips PW 9509 conductimeter. Literature methods were
Preparation of [PPh3(CH3)]2[(C6F5)2Pt(µ-PPh2)2Pt(CN)2] (6): KCN
(0.030 g, 0.460 mmol) was added to a solution of 1 (0.200 g,
3898
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Eur. J. Inorg. Chem. 2005, 3894–3901

A Dinuclear Phosphidoplatinum() Fragment
FULL PAPER
0.170 mmol) in acetone (10 mL) and the mixture was stirred at
room temperature for 15 h. [PPh3(CH3)]ClO4 (0.128 g, 0.339 mmol)
was then added and the mixture was concentrated to dryness.
CH2Cl2 (10 mL) was added to the white residue and then filtered.
The solution was concentrated to ca. 1 mL, iPrOH (10 mL) was
added and 6 crystallised as a white solid which was filtered off,
washed with 2 mL of iPrOH and vacuum-dried. Yield: 0.211 g
(73%). C76H56F10N2P4Pt2 (1701.38): calcd. C 53.65, H 3.31, N
(4283.8): calcd. C 49.35, H 2.63, N 1.31; found C 49.57, H 2.44, N
1.25. IR (nujol mull): ν = 797, 784, 774 (X-sensitive C F group),
˜
6
5
2164, 2157 ν(CϵN) cm–1. ΛM = 162 Ω–1 cm2 mol–1. 19F NMR
(282.4 MHz, [D6]acetone, 22°C): δ = –166.0 (4 p-F), –164.5 (8 m-
F), –163.1 (12 m + p-F), –112.2 (8 o-F), –112.2 (3JPt,F = 328 Hz, 8
o-F) ppm. 31P{1H} NMR (121.5 MHz, [D6]acetone, 22°C): δ =
–154.8 (JPt1,2 = 1835 Hz, PPh2), 26.9 (PPh3CH3) ppm.
,P
Preparation of [PPh3CH3]4[{(C6F5)2Pt(µ-PPh2)2Pt(µ-CN)}4] (9):
Complex 1 (0.056 g, 0.048 mmol) was added to a solution of 6
(0.080 g, 0.048 mmol) in acetone (10 mL) and the solution was
stirred at room temperature for 15 h. The solvent was evaporated
to leave ca. 2 mL and CHCl3 (8 mL) was added and the mixture
concentrated to ca. 5 mL. Complex 9 crystallised as a white solid
which was filtered off and washed with 1 mL of CHCl3. Yield:
0.076 g (57%). C224H152F40N4P12Pt8 (5592.2): calcd. C 48.12, H
1.64; found C 53.80, H 2.98, N 1.60. IR (nujol mull): ν = 782, 773
˜
(X-sensitive C6F5 group), 2122, 2113 ν(CϵN) cm–1. ΛM
=
91 Ω–1 cm2 mol–1. 19F NMR (282.4 MHz, [D6]acetone, 22°C): δ =
–166.4 (2 p-F), –164.6 (4 m-F), –111.7 (3JPt,F = 323 Hz, 4 o-F) ppm.
31P{1H} NMR (121.5 MHz, [D6]acetone, 22°C): δ = –150.3 (JPt1,2,P
= 1820 Hz, PPh2), 27.2 (PPh3CH3) ppm.
Preparation
of
[PPh3CH3]4[{(C6F5)2Pt(µ-PPh2)2Pt(µ-CN)2M-
2.70, N 1.00; found C 48.30, H 2.31, N 0.77. IR (nujol mull): ν =
˜
(C6F5)2}2]. M = Pt (7): cis-[Pt(C6F5)2(THF)2] (0.060 g, 0.089 mmol)
was added to a solution of 6 (0.150 g, 0.088 mmol) in CH2Cl2
(10 mL) and the solution was stirred for 1.5 h. The solvent was
evaporated to leave 2 mL while a white solid began to crystallise
and CHCl3 (5 mL) was added. Complex 7 was filtered off and
washed with 1 mL of cold CHCl3. Yield: 0.134 g (68%).
C176H112F40N4P8Pt6 (4461.2): calcd. C 47.38, H 2.53, N 1.25; found
781, 771 (X-sensitive C6F5 group), 2152 br. ν(CϵN) cm–1. ΛM
=
91 Ω–1 cm2 mol–1. 19F NMR (282.4 MHz, [D6]acetone, 22°C): δ =
–167.5 (4 p-F), –167.3 (4 p-F), –166.2 (12 m-F), –165.6 (4 m-F),
–114.0 (3JPt,F = 317 Hz, 16 o-F) ppm. 31P{1H} NMR (121.5 MHz,
[D6]acetone, 22°C): δ = –161.0 (JPt1,2,P = 1843 Hz, PPh2), –157.9
(JPt3,P = 1899, JPt4,P = 2400 Hz, PPh2), 23.0 (PPh3CH3) ppm.
C 47.03, H 2.03, N 1.19. IR (nujol mull): ν = 810, 800, 783, 773 Structural Analysis of Complexes 1·Me2CO and 8·3Me2CO·n-hex-
˜
(X-sensitive C6F5 group), 2164 br. ν(CϵN) cm–1. ΛM
106 Ω–1 cm2 mol–1. 19F NMR (282.4 MHz, [D6]acetone, 22°C): δ
=
ane: Crystal data and other details of the structure analysis are
presented in Table 3. Single crystals were mounted on quartz fibres
= –166.8 (4 p-F), –166.6 (4 p-F), –166.3 (8 m-F), –166.1 (8 m-F), in a random orientation and held in place with a fluorinated oil.
–117.7 (3JPt,F 505 = Hz, 8 o-F), –114.4 (3JPt,F = 333 Hz, 8 o-F)
ppm. 31P{1H} NMR (121.5 MHz, [D6]acetone, 22°C): δ = –157.2
Data collection was performed at 100 K with a Bruker Smart CCD
diffractometer using graphite-monochromated Mo-Kα radiation (λ
= 0.71073 Å) with a nominal crystal-to-detector distance of 6.0 cm.
Unit-cell dimensions were determined on the basis of the positions
of 9622 (1) or 7283 (8) reflections from the main dataset. For 1, a
hemisphere of data, based on three ω-scans runs (starting ω =
(JPt1,2 = 1831 Hz, PPh2), 23.1 (PPh3CH3) ppm. M = Pd (8): This
,P
complex was obtained [yield: 0.070 g (56%)] according to a similar
procedure to that used for 7 from 6 (0.100 g, 0.058 mmol) and cis-
[Pd(C6F5)2(THF)2] (0.034 g, 0.058 mmol). C176H112F40N4P8Pd2Pt4
Table 3. Crystal data and structure refinement for [(C6F5)2Pt(µ-PPh2)2Pt(NCCH3)2]·MeCO (1·Me2CO) and {(PPh3Me)2[(C6F5)2Pt(µ-
PPh2)2Pt(µ-CN)2Pd(C6F5)2]}2·3Me2CO·n-hexane (8·3 Me2CO·n-hexane).
1·Me2CO
8·3Me2CO·n-hexane
Empirical formula
Formula mass
T [K]
C40H26F10N2P2Pt2·Me2CO
1234.83
100(1)
0.71073
monoclinic
P21/n
12.2295(6)
39.6985(18)
17.1613(8)
90
100.560(1)
90
8190.6(7)
8
2.003
6.986
1.03–25.04
48272
14445 (0.0463)
14445/0/1085
1.047
R1 = 0.0315
wR2 = 0.0697
R1 = 0.0409
wR2 = 0.0730
C176H112F40N4P8PdPt2·3Me2CO·n-hexane
4544.04
100(1)
λ [Å]
0.71073
triclinic
Crystal system
Space group
a [Å]
b [Å]
c [Å]
α [º]
β [º]
¯
P
15.0079(6)
19.0293(8)
19.1387(8)
83.089(1)
97.706(11)
86.530(1)
4763.2(3)
1
1.584
3.269
1.73–28.53
44051
21666 (0.0306)
21666/0/1154
0.980
γ [º]
V [Å3]
Z
Dc [gcm–3]
µ (Mo-Kα) [mm–1]
θ range [º]
Data collected
Independent data (Rint
)
Data/restraints/parameters
Goodness-of-fit on F2[a]
Final R indices [I Ͼ 2σ(I)][b]
R1 = 0.0389
wR2 = 0.1001
R1 = 0.0551
wR2 = 0.1046
R indices (all data)
[a] Goodness-of-fit = [∑w(Fo – Fc ) /(Nobs – Nparam)]0.5. [b] R1 = ∑(|Fo| – |Fc|)/∑|Fo|; wR2 = [∑w(Fo – Fc ) /∑w(Fo2)2]0.5
.
2
2 2
2
2 2
Eur. J. Inorg. Chem. 2005, 3894–3901
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3899

I. Ara, N. Chaouche, J. Forniés, C. Fortuño, A. Kribii, A. Martín
FULL PAPER
[16] E. Alonso, J. M. Casas, F. A. Cotton, X. J. Feng, J. Forniés, C.
Fortuño, M. Tomás, Inorg. Chem. 1999, 38, 5034–5040.
[17] E. Alonso, J. Forniés, C. Fortuño, A. Martín, A. G. Orpen,
Organometallics 2000, 19, 2690–2697.
[18] L. R. Falvello, J. Forniés, C. Fortuño, F. Martínez, Inorg.
Chem. 1994, 33, 6242–6246.
[19] N. Chaouche, J. Forniés, C. Fortuño, A. Kribii, A. Martín, P.
Karipidis, A. C. Tsipis, C. A. Tsipis, Organometallics 2004, 23,
1797–1810.
[20] E. Alonso, J. Forniés, C. Fortuño, M. Tomás, J. Chem. Soc.,
Dalton Trans. 1995, 3777–3784.
[21] J. Forniés, C. Fortuño, R. Navarro, F. Martínez, A. J. Welch,
J. Organomet. Chem. 1990, 394, 643–658.
[22] R. Usón, J. Forniés, Adv. Organomet. Chem. 1988, 28, 219–297.
[23] E. J. Maslowsky, Vibrational Spectra of Organometallic Com-
pounds, Wiley, New York, 1997.
[24] B. Longato, G. Bandoli, A. Mucci, L. Schenetti, Eur. J. Inorg.
Chem. 2001, 3021–3029.
[25] A. Doppiu, M. A. Cinellu, G. Minghetti, S. Stoccoro, A.
Zucca, M. Manassero, M. Sansoni, Eur. J. Inorg. Chem. 2000,
2555–2563.
–28°) at φ values 0, 90, and 180 with the detector at 2θ = 28°,
was collected. At each of these runs, frames (606, 435 and 230
respectively) were collected at 0.3° intervals and 10 s per frame. For
8, a complete sphere of data was collected based on three ω-scans
runs at φ values of 0, 120 and 240. At each of these runs, 606
frames were collected at 0.3° intervals and 30 s per frame. The dif-
fraction frames were integrated using the SAINT package[51] and
corrected for absorption with SADABS.[52] Lorentz and polarisa-
tion corrections were also applied. The structures were solved by
direct methods. All non-hydrogen atoms of the complexes were as-
signed anisotropic displacement parameters. The hydrogen atoms
were constrained to idealised geometries and assigned isotropic dis-
placement parameters equal to 1.2- or 1.5-times the Uiso values of
their respective parent atoms. After all atoms of the molecules had
been located, there still remained some areas of electron density
that were modelled as the lattice solvent. Final difference electron
density maps showed, only in the case of 8, some peaks above
1 eÅ–3 (max. 2.69, largest diff. hole –1.07), most of them close to
the heavy metal atoms and with no chemical meaning, others were
located in the solvent area. The crystals lost solvent very rapidly
and because of this their quality was not good. The structures were
refined using the SHELXL-97 program.[53] CCDC-268963 (1) and
-268963 (8) contain the supplementary crystallographic data for
this paper. These data can be obtained free of charge from The
Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/
data_request/cif.
[26] P. J. J. Albietz, K. Yang, R. Eisenberg, Organometallics 1999,
18, 2747–2749.
[27] P. Steenwinkel, H. Kooijman, W. J. J. Smeets, A. L. Spek, D. M.
Grove, G. van Koten, Organometallics 1998, 17, 5411–5426.
[28] R. Buchner, J. S. Field, R. J. Haines, C. T. Cunningham, D. R.
McMillin, Inorg. Chem. 1997, 36, 3952–3956.
[29] D. Armentano, G. Munno, F. Lloret, M. Julve, J. Curély, A. M.
Babb, J. Y. Lu, New J. Chem. 2003, 27, 161–165.
[30] J. M. Herrera, D. Armentano, G. Munno, F. Lloret, M. Julve,
M. Verdaguer, New J. Chem. 2003, 27, 128.
[31] L. M. Toma, R. Lescouezec, L. D. Toma, F. Lloret, M. Julve,
J. Vaissermann, M. Andruh, J. Chem. Soc., Dalton Trans. 2002,
3171–3176.
[32] S. Triki, F. Thétiot, J.-R. Galán-Mascarós, J. S. Pala, K. R.
Dunbar, New J. Chem. 2001, 25, 954–958.
Acknowledgments
We thank the Ministerio de Ciencia y Tecnología y Fondos
FEDER (Project BQU2002-03997-C02-02) for financial support
and the Agencia Española de Cooperación Internacional (Minis-
terio de Asuntos Exteriores) for a grant to N.C.
[33] J. M. Casas, B. Diosdado, J. Forniés, private communication.
[34] F. Bérézovsky, A. A. Hajem, S. Triki, J. Sala-Pala, P. Molinié,
Inorg. Chim. Acta 1999, 284, 8–13.
[35] H. Vahrenkamp, A. Geiss, G. N. Richardson, J. Chem. Soc.,
Dalton Trans. 1997, 3643–3651.
[1] J. Forniés, C. Fortuño, S. Ibáñez, A. Martín, A. C. Tsipis, C. A.
Tsipis, Angew. Chem. Int. Ed. 2005, 44, 2407–2410.
[2] B. J. Holliday, C. A. Mirkin, Angew. Chem. Int. Ed. 2001, 40,
2022–2043.
[3] M. Fujita, K. Umemoto, M. Yoshizawa, N. Fujita, T. Kusu-
kawa, K. Biradha, Chem. Commun. 2001, 509–518.
[4] S. Leininger, B. Olenyuk, P. J. Stang, Chem. Rev. 2000, 100,
853–907.
[36] H. Oshio, M. Yamamoto, T. Ito, Inorg. Chem. 2002, 41, 5817–
5820.
[37] E. Colacio, J. M. Domínguez-Vera, F. Lloret, J. M. Moreno-
Sánchez, R. Kivekas, A. Rodríguez, R. Sillanpaa, Inorg. Chem.
2003, 42, 4209–4214.
[38] R. Lescouezec, F. Lloret, M. Julve, J. Vaissermann, M. Verdag-
uer, R. Llusar, S. Uriel, Inorg. Chem. 2001, 40, 2065–2072.
[39] H.-Z. Kou, B. C. Zhou, D.-Z. Liao, R.-J. Wang, Y. Li, Inorg.
Chem. 2002, 41, 6887–6891.
[40] A. Figuerola, C. Díaz, M. S. El-Fallah, J. Ribas, M. Maestro,
J. Mahía, Chem. Commun. 2001, 1204–1205.
[41] M. Ohba, H. Okawa, Coord. Chem. Rev. 2000, 198, 313–328.
[42] J. Forniés, J. Gómez, E. Lalinde, M. T. Moreno, Chem. Eur. J.
2004, 10, 888–898.
[5] Z. Qin, M. C. Jennings, R. J. Puddephatt, Inorg. Chem. 2003,
42, 1956–1965.
[6] O. V. Dolomanov, A. J. Blake, N. R. Champness, M. Schröder,
C. Wilson, Chem. Commun. 2003, 682–683.
[7] T. Moriuchi, M. Karnikawa, S. Bandoh, T. Hirao, Chem. Com-
mun. 2002, 1476–1477.
[8] P. J. Stang, D. H. Cao, S. Saito, A. M. Arif, J. Am. Chem. Soc.
1995, 117, 6273–6283.
[9] P. J. Stang, D. H. Cao, K. Chen, G. M. Gray, D. C. Muddiman,
R. D. Smith, J. Am. Chem. Soc. 1997, 119, 5163–5168.
[10] J. A. Whiteford, C. V. Lu, P. J. Stang, J. Am. Chem. Soc. 1997,
119, 2524–2533.
[43] L. R. Falvello, M. Tomás, Chem. Commun. 1999, 273–274.
[44] S.-W. Lai, K.-K. Cheung, M. C.-W. Chan, C.-M. Che, Angew.
Chem. Int. Ed. 1998, 37, 182–184.
[45]
[46]
[47]
[48]
[49]
[50]
R. Usón, J. Forniés, P. Espinet, R. Navarro, M. A. Usón, Inorg.
Chim. Acta 1979, 33, L103–L105.
R. Usón, J. Forniés, P. Espinet, A. Arribas, J. Organomet.
Chem. 1980, 199, 111–118.
R. Usón, J. Forniés, P. Espinet, Synth. React. Inorg. Met.-Org.
Chem. 1983, 13, 513–526.
I. Escorihuela, L. R. Falvello, M. Tomás, Inorg. Chem. 2001,
40, 636–640.
K. R. Dunbar, R. A. Heintz, Prog. Inorg. Chem. 1997, 45, 283–
391.
R. Usón, J. Forniés, M. Tomás, B. Menjón, Organometallics
1986, 5, 1581–1584.
[11] F. A. Cotton, C. Lin, C. A. Murillo, Chem. Commun. 2001, 11–
12.
[12] F. A. Cotton, C. Lin, C. A. Murillo, Acc. Chem. Res. 2001, 34,
759–771.
[13] E. Alonso, J. Forniés, C. Fortuño, A. Martín, A. G. Orpen,
Organometallics 2003, 22, 2723–2728.
[14] L. R. Falvello, J. Forniés, C. Fortuño, F. Durán, A. Martín,
Organometallics 2002, 21, 2226–2234.
[15] E. Alonso, J. M. Casas, J. Forniés, C. Fortuño, A. Martín,
A. G. Orpen, C. A. Tsipis, A. C. Tsipis, Organometallics 2001,
20, 5571–5582.
3900
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2005, 3894–3901

A Dinuclear Phosphidoplatinum() Fragment
FULL PAPER
[51] SAINT-Plus (version 6.02), 6.02 ed., Bruker Analytical X-ray
Systems INC., Madison, USA, Madison, USA, 1999.
[52] G. M. Sheldrick, SADABS (version 2.03), University of
Göttingen, Germany, Germany, 1996.
[53] G. M. Sheldrick, SHELXL-97, University of Göttingen, Ger-
many, Germany, 1997.
Received: April 16, 2005
Published Online: August 29, 2005
Eur. J. Inorg. Chem. 2005, 3894–3901
www.eurjic.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3901