Synthesis, structure and reactivity of homo- and heterobimetallic complexes of the general formula [Cp*Ru(μ-Cl)3ML] [LM = (arene)Ru, Cp*Rh, Cp*Ir]

Article abstract of DOI:10.1002/ejic.200500692

The homo- and heterobimetallic complexes [Cp*Ru(μ-Cl) ₃-ML] [LM = (C₆H₆)Ru, (cymene)Ru, (1,3,5-C ₆H₃iPr₃)Ru, Cp*Rh, Cp*Ir] were prepared by reaction of [Cp*Ru(μ-OMe)]₂ with Me ₃SiCl and subsequent addition of [LMCl₂]₂. The complexes [Cp*Ru(μ-Cl)₃Ru(cymene)] and [Cp*Ru(μ-Cl) ₃-IrCp*] were characterized by single-crystal X-ray analyses. In crossover experiments with [Cp*Rh(μ-Cl)₃RuCl(PPh ₃)₂] and [Cp*Ru(μ-Cl)₃Ru(1,3,5-C ₆H₃iPr₃)] in CD₂Cl₂, a dynamic equilibrium with the complexes [Cp*Rh(μ-Cl)₃RuCp*] and [(1,3,5-C₆H₃iPr₃)Ru(μ-Cl) ₃RuCl(PPh₃)₂] was rapidly established, demonstrating the kinetic lability of the triple chloro bridge. Upon reaction of [Cp*Rh(μ-Cl)₃RuCp*] with benzene, the ionic complex [Cp*Ru(C₆H₆)][Cp*RhCl₃] was formed, which was characterized by X-ray crystallography. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.

Full text of DOI:10.1002/ejic.200500692

FULL PAPER
DOI: 10.1002/ejic.200500692
Synthesis, Structure and Reactivity of Homo- and Heterobimetallic Complexes
of the General Formula [Cp*Ru(µ-Cl)3ML] [LM = (arene)Ru, Cp*Rh, Cp*Ir]
Laurent Quebatte,[a] Rosario Scopelliti,[a][‡] and Kay Severin*[a]
Keywords: Heterometallic complexes / Iridium / Rhodium / Ruthenium
The homo- and heterobimetallic complexes [Cp*Ru(µ-Cl)3-
ML] [LM (C6H6)Ru, (cymene)Ru, (1,3,5-C6H3iPr3)Ru,
equilibrium with the complexes [Cp*Rh(µ-Cl)3RuCp*] and
[(1,3,5-C6H3iPr3)Ru(µ-Cl)3RuCl(PPh3)2] was rapidly estab-
lished, demonstrating the kinetic lability of the triple chloro
bridge. Upon reaction of [Cp*Rh(µ-Cl)3RuCp*] with ben-
zene, the ionic complex [Cp*Ru(C6H6)][Cp*RhCl3] was
formed, which was characterized by X-ray crystallography.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2006)
=
Cp*Rh, Cp*Ir] were prepared by reaction of [Cp*Ru(µ-
OMe)]2 with Me3SiCl and subsequent addition of [LMCl2]2.
The complexes [Cp*Ru(µ-Cl)3Ru(cymene)] and [Cp*Ru(µ-Cl)3-
IrCp*] were characterized by single-crystal X-ray analyses.
In crossover experiments with [Cp*Rh(µ-Cl)3RuCl(PPh3)2]
and [Cp*Ru(µ-Cl)3Ru(1,3,5-C6H3iPr3)] in CD2Cl2, a dynamic
tained in metathesis reactions starting from the correspond-
ing homodimeric compounds. Reactions of this kind were
first described by the groups of Stone[5] and Masters[6] in
the 1970s. More recent investigations have shown that this
method is quite general.[7,8] Mixed complexes with three
halogeno-bridges can likewise be obtained in metathesis re-
actions[9,10] but alternative pathways such as ligand-trans-
fer[11] or substitution[3a,3b,12] reactions have also been ex-
plored.[4] The various methods allow the synthesis of a
structurally diverse set of homo- and heterobimetallic com-
plexes in relatively short time. This is of interest for the
generation of catalyst libraries in combinatorial catalysis.[3c]
In the following, we introduce a new procedure that allows
the synthesis of complexes of the general formula
[Cp*Ru(µ-Cl)3ML] [LM = (arene)Ru, Cp*Rh, Cp*Ir] in ex-
cellent yields.
Introduction
Bimetallic complexes, in which two different metal frag-
ments are connected by either two or three halogeno brid-
ges, have been employed as catalyst precursors for ring-
opening and ring-closing metathesis reactions,[1] for the Op-
penauer-type oxidation of alcohols,[2] and for atom-transfer
radical reactions.[3] The heterobimetallic RhI–RuII complex
1, for example, can be used as an efficient catalyst for the
oxidation of secondary alcohols under mild conditions,[2a]
whereas the RhIII–RuII complex 2[3c] and the RuII–RuII
complex 3[3a] are among the most active catalysts available
for the atom-transfer radical addition of CCl4 and CHCl3
to olefins.
Results and Discussion
For the synthesis of mixed complexes containing the
Cp*RuCl fragment, the tetrameric complex [Cp*RuCl]4 (4)
seemed to be well suited as it is known that the chloro
bridges of 4 can be easily cleaved.[13–16] The reaction of 4
with two equivalents of the dimeric half-sandwich complex
[(π-ligand)MCl2]2 was thus expected to give the mixed com-
plex [Cp*Ru(µ-Cl)3M(π-ligand)] in an entropically favored
reaction. Complex 4 can be obtained by reduction of
The synthesis of mixed, halogeno-bridged complexes can
be accomplished by several synthetic routes.[4] Mixed com-
plexes with two halogeno bridges are most conveniently ob-
[14]
[Cp*RuCl2]2 with LiHBEt3 or with Zn.[15] Alternatively,
it can be obtained by reaction of the methoxy-bridged com-
plex [Cp*Ru(µ-OMe)]2 (5) with Me3SiCl.[16] We chose the
latter method for our reactions.
For the synthesis of the homo- and heterobimetallic com-
plexes 6–10, the tetramer 4 was generated in situ by ad-
dition of Me3SiCl to complex 5 in CH2Cl2. Subsequent ad-
[a] Institut des Sciences et Ingénierie Chimiques, École Polytech-
nique Fédérale de Lausanne (EPFL)
1015 Lausanne, Switzerland
Fax: +41-21-693-9305
E-mail: kay.severin@epfl.ch
[‡] X-ray structural analysis.
Eur. J. Inorg. Chem. 2006, 231–236
© 2006 Wiley-VCH Verlag GmbH & Co. KgaA, Weinheim
231

L. Quebatte, R. Scopelliti, K. Severin
FULL PAPER
dition of [(π-ligand)MCl2]2 gave the mixed products 6–10
(Scheme 1). Complex 4 displays a high solubility in a vari-
ety of nonpolar organic solvents and even in hydrocarbons
such as pentane. It was thus possible to use a slight excess
of 5 (1.2×) with respect to the dimer [(π-ligand)MCl2]2 be-
cause additional 4 could easily be removed by washing with
pentane. The homobimetallic product 10, on the other
hand, is itself soluble in pentane. We therefore used a slight
excess of [(1,3,5-C6H3iPr3)RuCl2]2 (1.2×) and purified the
product 10 by extraction with pentane.
Figure 1. ORTEP[18] drawing of the molecular structure of 7 in the
crystal. The hydrogen atoms have been omitted for clarity. Selected
bond lengths [Å] and angles [°]: Ru1–Cl1 2.5591(13), Ru1–Cl2
2.5024(14), Ru1–Cl3 2.5075(14), Ru2–Cl1 2.4521(13), Ru2–Cl2
2.4222(13), Ru2–Cl3 2.4205(13); Ru1–Cl1–Ru2 83.70(4), Ru1–Cl2–
Ru2 85.53(4), Ru1–Cl3–Ru2 85.45(4), Cl1–Ru1–Cl2 76.70(4), Cl1–
Ru2–Cl2 80.23(5).
Scheme 1. Synthesis of the complexes 6–10.
1
The new complexes 6–10 were characterized by H and
13C NMR spectroscopy and by elemental analysis. In ad-
dition, complexes 7 and 9 were analyzed by single-crystal
X-ray analysis (Figures 1 and 2, respectively). The crystallo-
graphic analyses confirmed that the two metal fragments
are connected by three chloro bridges. The planes defined
by the π-ligands and the plane defined by the three bridging
chloro ligands are nearly parallel to each other. For com-
plex 7, the distances of the chloro atoms to the Ru atom
attached to the cymene π-ligand (Ru–Cl = 2.42–2.45 Å) are
shorter than those to the Ru atom attached to the Cp* li-
gand (Ru–Cl = 2.50–2.56 Å). A likely explanation for this
Figure 2. ORTEP[18] drawing of the molecular structure of 9 in the
crystal. Only one of the two crystallographically independent mole-
cules is shown. The hydrogen atoms have been omitted for clarity.
Selected bond lengths [Å] and angles [°]: Ru1b–Cl1b 2.516(3),
Ru1b–Cl2b 2.509(3), Ru1b–Cl3b 2.523(3), Ir1b–Cl1b 2.413(3),
difference is the increased Lewis acidity of the (cymene)- Ir1b–Cl2b 2.410(3), Ir1b–Cl3b 2.428(3); Ru1b–Cl1b–Ir1b 85.32(8),
Ru2+ fragment compared to the Cp*Ru+ fragment. The two
Ru atoms in 7 are 3.344(8) Å apart from each other. This is
Ru1b–Cl2b–Ir1b 85.54(8), Ru1b–Cl3b–Ir1b 84.86(8), Cl1b–Ru1b–
Cl2b 77.90(10), Cl1b–Ir1b–Cl2b 81.85(11).
longer than what is found for the cationic dimer [(cymene)-
Ru(µ-Cl)3Ru(cymene)]+ [Ru···Ru = 3.283(3) Å].[17]
In the highly symmetrical dimer 9, a Cp*Ru+ fragment deactivated by the formation of face-bridged dimers.[20] In
is connected by three chloro bridges to a Cp*Ir2+ fragment. order to investigate the kinetic stability of the bimetallic
As was observed for 7, the M–Cl bond lengths are shorter complexes described above, crossover experiments were per-
for the more Lewis-acidic metal fragment: the Ir–Cl dis- formed. Thus, a solution of complex 2 was mixed with a
1
tances range from 2.41 to 2.45 Å, whereas the Ru–Cl dis- solution of complex 10 (both in CD2Cl2) and a H NMR
tances range from 2.50 to 2.52 Å. Complex 9 is isoelectronic spectrum was recorded immediately after mixing. Apart
with the mixed-valence RuII–RuIII complex [Cp*Ru(µ-Cl)3- from signals of the complexes 2 and 10, the signals of two
RuCp*] described by Koelle et al.,[16a,19] although due to other complexes were observed (Figure 3). These were iden-
the lack of structural data for the latter a direct comparison tified as the mixed complexes 8 and 11 by comparison with
1
was not possible.
the H NMR spectra of authentic samples (Scheme 2). The
The prevalence of polynuclear ruthenium complexes with time-invariant integrals of the respective signals showed a
the Ru(µ-Cl)3M structural motif suggests that the connec- nearly equimolar distribution of the four species. This sug-
tion by three chloro bridges is thermodynamically very gests that a dynamic equilibrium between the four com-
stable. In fact, it has been shown that some catalysts can be plexes is rapidly established after the mixing process.
232
www.eurjic.org
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2006, 231–236

Homo- and Heterobimetallic Complexes of Ru
FULL PAPER
Scheme 3. The ionic complex 12 is obtained by reaction of complex
8 with benzene.
The structure of complex 12 was analyzed by single-crys-
tal X-ray analysis (Figure 4). The bond lengths found for
the cation [Cp*Ru(C6H6)]+ (Ru–Cbenzene = 2.21–2.22 Å;
Ru–CCp* = 2.18–2.19 Å) are very similar to those reported
for related [Cp*Ru(arene)]+ complexes.[22a,22d,23] The corre-
sponding anion [Cp*RhCl3]– displays a typical “piano-
stool” geometry, with Rh–Cl bond lengths of 2.4114(14)
and 2.420(2) Å, respectively. The formation of this anion is
rather unusual[24] given the thermodynamic stability of the
[Cp*Rh(µ-Cl)3RhCp*]+ cation,[11,25] and underlines the fact
that the generation of [Cp*Ru(C6H6)]+ is the driving force
for the reaction.
Figure 3. Part of the 1H NMR spectrum of a) complex 10, b) com-
plex 2, and c) an equimolar mixture of complex 2 and 10, for which
the additional signals of the complexes 8 and 11 are visible.
Scheme 2. In solution (CD2Cl2), complexes 2 and 10 are in a dy-
namic equilibrium with complexes 8 and 11.
Figure 4. ORTEP[18] drawing of the molecular structure of 12 in
the crystal. The hydrogen atoms have been omitted for clarity. Se-
lected bond lengths [Å] and angles [°]: Rh1–Cl1 2.4114(14), Rh1–
Cl2 2.420(2); Cl1–Rh1–Cl2 90.97(5), Cl1–Rh1–Cl1Ј 91.15(7). Ј: x,
The results described above are in agreement with a re-
port by Stephenson et al. in which they show that upon
mixing of [(C6H6)Ru(µ-Cl)3Ru(C6H6)]+ and [(C6H6)Os(µ-
Cl)3Os(C6H6)]+, the heterobimetallic complex [(C6H6)Ru(µ- 1/2 – y, z.
Cl)3Os(C6H6)]+ is obtained in equilibrium with the two
homobimetallic starting materials.[21] We have previously
shown that the triply bridged complex [(dcypb)(N2)Ru(µ-
Conclusions
Cl)3RuCl(dcypb)] reacts rapidly with doubly bridged com-
plexes of the general formula [LMCl2]2 [LM = (cymene)-
Bimetallic complexes, in which two different metal frag-
Ru, Cp*Rh, Cp*Ir] to give the mixed complexes [(dcypb)- ments are connected by either two or three halogeno
ClRu(µ-Cl)3ML].[9b] Taken together, these results point to bridges, have recently emerged as a promising new class of
the fact that [LnRu(µ-Cl)3MLЈn] complexes are generally catalysts.[1–3] New synthetic routes to generate such com-
very labile, despite their apparent thermodynamic stability. plexes are thus highly warranted. In this report, we have
Complexes 6–10 are soluble in a variety of organic sol- described the homo- and heterobimetallic complexes
vents such as acetone, THF, CH2Cl2, and Et2O. The very [Cp*Ru(µ-Cl)3ML] [LM = (C6H6)Ru, (cymene)Ru, (1,3,5-
lipophilic 10 can even be dissolved in pentane. Aromatic C6H3iPr3)Ru, Cp*Rh, Cp*Ir]. They can be prepared in ex-
solvents, on the other hand, are not suited because of the cellent yield by reaction of [Cp*Ru(µ-OMe)]2 with Me3SiCl
very high tendency of the Cp*Ru+ fragment to form sand- and subsequent addition of [LMCl2]2. Crossover experi-
wich complexes of the general formula [Cp*Ru(arene)]- ments have demonstrated that these complexes undergo fast
X.[14–16,22] When complex 8 was dissolved in benzene, crys- scrambling reactions with other triply bridged complexes.
tals of the ionic complex [Cp*Ru(C6H6)][Cp*RhCl3] (12) The dimers are thus kinetically very labile, a fact which is
formed after a few hours (Scheme 3). Larger amounts of 12 of importance for possible catalytic applications. In a reac-
could be obtained by slow diffusion of hexane into a solu- tion with benzene, the chloro bridge of the complex
tion of 8 in benzene.
[Cp*Ru(µ-Cl)3RhCp*] is cleaved in a completely asymmet-
Eur. J. Inorg. Chem. 2006, 231–236
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
233

L. Quebatte, R. Scopelliti, K. Severin
FULL PAPER
ric fashion to give the cation [Cp*Ru(C6H6)]+ and the anion
[Cp*RhCl3]–. This type of reactivity is unusual for [LnRu(µ-
Cl)3MLЈn] complexes but can be explained by the high in-
trinsic affinity of the Cp*Ru+ fragment for aromatic com-
pounds.
C16H21Cl3Ru2·1/6C5H12 (533.9): calcd. C 37.87, H 4.34; found C
37.96, H 4.51.
Complex 7: Red powder. Crystals suitable for X-ray analysis were
obtained by slow diffusion of pentane into a solution of 7 in dichlo-
romethane. 1H NMR (400 MHz, CD2Cl2): δ = 1.29 [d, 3J = 7.1 Hz,
6 H, CH(CH3)2], 1.51 (s, 15 H, CH3, Cp*), 2.18 (s, 3 H, CH3,
cymene), 2.82 [sept, 3J = 7.1 Hz, 1 H, CH(CH3)2], 5.21 (d, 3J =
3
6.0 Hz, 4 H, CH), 5.43 (d, J = 6.0 Hz, 4 H, CH) ppm. 13C NMR
Experimental Section
(101 MHz, CD2Cl2): δ = 10.4 (CH3, Cp*), 19.0, 22.4 (CH3, cy-
mene), 31.6 [CH(CH3)2], 70.6 (C, Cp*), 77.8, 78.9 (CH, cymene),
95.3, 100.3 (C, cymene) ppm. C20H29Cl3Ru2 (577.9): calcd. C 41.56,
H 5.06; found C 41.56, H 5.23.
General: All reactions were performed under an atmosphere of dry
dinitrogen. The solvents and Me3SiCl were distilled from appropri-
ate drying agents and stored under dinitrogen. The complexes
[Cp*Ru(OMe)]2,[26]
[(cymene)RuCl2]2,[27]
[(C6H6)RuCl2]2,[28]
Complex 8: Red powder. 1H NMR (400 MHz, CD2Cl2): δ = 1.52
[Cp*RhCl2]2,[29] [Cp*IrCl2]2,[29] [(1,3,5-C6H3iPr3)RuCl2]2,[30] and
[Cp*Rh(µ-Cl)3RuCl(PPh3)2] (2)[2b] were prepared according to lit-
erature procedures. An authentic sample of complex 11 was synthe-
sized by mixing equimolar amounts of [(PPh3)2ClRu(µ-Cl)3Ru(ace-
tone)(PPh3)2] and [(1,3,5-C6H3iPr3)RuCl2]2 in CH2Cl2.[9b] The 1H
and 13C NMR spectra were recorded on a Bruker Advance DPX
400 spectrometer with the residual protonated solvent as internal
standards. All spectra were recorded at room temperature.
(Cp*Ru), 1.61 (Cp*Rh) ppm. 13C NMR (101 MHz, CD2Cl2): δ =
1
9.5, 10.5 (CH3, Cp*), 70.0 (C, Cp*Ru), 93.6 (d, JC,Rh = 10.1 Hz,
C, Cp*Rh) ppm. C20H30Cl3RhRu (580.0): calcd. C 41.36, H 5.21;
found C 41.51, H 5.26.
Complex 9: Orange powder. Crystals suitable for X-ray analysis
were obtained by slow diffusion of pentane into a solution of 9 in a
mixture of dichloromethane and hexane (1:9). 1H NMR (400 MHz,
CD2Cl2): δ = 1.57 (Cp*), 1.58 (Cp*) ppm. 13C NMR (101 MHz,
CD2Cl2): δ = 9.5, 10.5 (CH3), 70.3, 85.2 (C) ppm. C20H30Cl3IrRu
(670.1): calcd. C 35.85, H 4.51; found C 35.99, H 4.57.
General Method for the Synthesis of Complexes 6–9: Me3SiCl
(71 µL, 561 µmol) was added to a solution of [Cp*Ru(OMe)]2
(100 mg, 187 µmol) in CH2Cl2 (10 mL). After addition of the re-
spective dimer [(π-ligand)MCl2]2 (156 µmol), the solution was
stirred for 20 min. The solvent was then removed in vacuo and the
resulting powder was suspended in pentane (10 mL) in order to
dissolve the excess of complex [CpRuCl]4. The product was isolated
by filtration, washed with additional pentane (3×2 mL) and dried
under vacuum (yield: 88–96%).
Synthesis of Complex 10: Me3SiCl (30 µL, 240 µmol) was added to
a solution of [Cp*Ru(OMe)]2 (43 mg, 80 µmol) in CH2Cl2 (5 mL).
After addition of [(C6H3iPr3)RuCl2]2 (72 mg, 96 µmol), the solution
was stirred for 20 min. The solvent was then removed in vacuo and
the product was extracted with pentane (2×5 mL). The product
was isolated by evaporation of the pentane and drying under vac-
1
uum. Yield: 94 mg (92%). H MNR (400 MHz, CD2Cl2): δ = 1.31
Complex 6: Red powder. 1H NMR (400 MHz, CD2Cl2): δ = 1.50
(Cp*), 5.60 (benzene) ppm. 13C NMR (101 MHz, CD2Cl2): δ =
10.4 (CH3, Cp*), 70.9 (C, Cp*), 80.5 (benzene) ppm.
[d, J = 7.1 Hz, 18 H, CH(CH3)2], 1.50 (s, 15 H, CH3, Cp*), 2.90
3
[sept, 3J = 7.1 Hz, 3 H, CH(CH3)2], 5.09 (s, 3 H, CH) ppm. 13C
NMR (101 MHz, CD2Cl2): δ = 10.5 (CH3, Cp*), 22.5 [CH(CH3)2],
Table 1. Crystallographic data for complexes 7, 9, and 12.
7
9
12
Empirical formula
Molecular weight [gmol–1]
Crystal size
Crystal system
Space group
C20H29Cl3Ru2
577.92
0.17×0.12×0.10
monoclinic
P21/c
C20H30Cl3IrRu
670.06
0.30×0.28×0.11
monoclinic
I2/a
C26H36Cl3RhRu
658.88
0.19×0.12×0.11
orthorhombic
Pnma
a [Å]
b [Å]
c [Å]
α [°]
11.3160(6)
17.108(3)
11.617(2)
90
27.9257(14)
10.6205(3)
30.1330(14)
90
19.069(3)
12.2265(7)
11.346(3)
90
β [°]
100.473(10)
90
2211.4(6)
4
1.736
140(2)
91.031(4)
90
8935.6(7)
16
1.992
140(2)
90
90
2645.2(7)
4
1.654
140(2)
1.510
3.25 to 25.03
γ [°]
Volume [Å3]
Z
Density [gcm–3]
Temperature [K]
Absorption coefficient [mm–1]
Θ range [°]
1.730
3.00 to 25.02
6.987
3.19 to 25.03
Index ranges
–12Ǟ 12, –20 Ǟ 20, –13 Ǟ 13 –33 Ǟ 33, –11 Ǟ 11, –35 Ǟ 35 –22Ǟ 22, –13 Ǟ 13, –13 Ǟ 13
Reflections collected
Independent reflections
Absorption correction
Max. and min. transmission
Data / restraints / parameters
Goodness-of-fit on F2
Final R indices [I Ͼ 2σ(I)]
R indices (all data)
Largest diff. peak/hole [eÅ–3]
13083
3714 (Rint = 0.0362)
semi-empirical
24673
7445 (Rint = 0.0333)
semi-empirical
16451
2352 (Rint = 0.0444)
semi-empirical
0.8179 and 0.6935
3714 / 0 / 226
1.114
0.4376 and 0.2545
7445 / 0 / 451
1.061
0.8633 and 0.7484
2352 / 0 / 152
1.151
R1 = 0.0365, wR2 = 0.0880
R1 = 0.0470, wR2 = 0.0955
0.739 and –0.646
R1 = 0.0422, wR2 = 0.0965
R1 = 0.0522, wR2 = 0.1001
1.778 and –1.723
R1 = 0.0410, wR2 = 0.0853
R1 = 0.0501, wR2 = 0.0896
0.941 and –0.745
234
www.eurjic.org
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2006, 231–236

Homo- and Heterobimetallic Complexes of Ru
FULL PAPER
Angew. Chem. Int. Ed. 2004, 43, 1520–1524; d) B. De Clerq, F.
Verpoort, Tetrahedron Lett. 2002, 43, 4687–4690.
For an overview see: K. Severin, Chem. Eur. J. 2002, 8, 1515–
1518.
M. I. Bruce, M. Z. Iqbal, F. G. A. Stone, J. Organomet. Chem.
1972, 40, 393–401.
a) A. A. Kiffen, C. Masters, J. P. Visser, J. Chem. Soc., Dalton
Trans. 1975, 1311–1315; b) C. Masters, J. P. Visser, J. Chem.
Soc., Chem. Commun. 1974, 932–933.
a) E. Corradi, N. Masciocchi, G. Pályi, R. Ugo, A. Vizi-Orosz,
C. Zucchi, A. Sironi, J. Chem. Soc., Dalton Trans. 1997, 4651–
4655; b) J. D. Scott, R. J. Puddephatt, Organometallics 1986, 5,
1253–1257; c) H. C. Clark, G. Ferguson, V. K. Jain, M. Parvez,
Inorg. Chem. 1986, 25, 3808–3811; d) H. C. Clark, G. Fergu-
son, V. K. Jain, M. Parvez, Inorg. Chem. 1985, 24, 1477–1482.
a) M. Öhm, A. Schulz, K. Severin, Eur. J. Inorg. Chem. 2000,
2623–2629; b) K. Polborn, K. Severin, J. Chem. Soc., Dalton
Trans. 1999, 759–764; c) K. Polborn, K. Severin, Eur. J. Inorg.
Chem. 1998, 1187–1192; d) K. Severin, K. Polborn, W. Beck,
Inorg. Chim. Acta 1995, 240, 339–346.
a) S. Gauthier, R. Scopelliti, K. Severin, Helv. Chim. Acta 2005,
88, 435–446; b) S. Gauthier, L. Quebatte, R. Scopelliti, K. Seve-
rin, Chem. Eur. J. 2004, 10, 2811–2821; c) A. C. da Silva, H.
Piotrowski, P. Mayer, K. Polborn, K. Severin, J. Chem. Soc.,
Dalton Trans. 2000, 2960–2963.
a) T. Arthur, T. A. Stephenson, J. Organomet. Chem. 1981, 208,
369–387; b) T. Arthur, T. A. Stephenson, J. Organomet. Chem.
1979, 168, C39–C41.
S. Gauthier, L. Quebatte, R. Scopelliti, K. Severin, Inorg.
Chem. Commun. 2004, 7, 708–712.
a) A.-R. Al-Ohaly, J. F. Nixon, Inorg. Chim. Acta 1985, 103,
83–93; b) R. A. Head, J. F. Nixon, J. Chem. Soc., Dalton Trans.
1978, 909–912.
a) U. Koelle, B.-S. Kang, U. Englert, J. Organomet. Chem.
1991, 420, 227–235; b) P. J. Fagan, W. S. Mahoney, J. C. Calab-
rese, I. D. Williams, Organometallics 1990, 9, 1843–1852; c)
B. K. Campion, R. H. Heyn, T. D. Tilley, J. Chem. Soc., Chem.
Commun. 1988, 278–280.
P. J. Fagan, M. D. Ward, J. C. Calabrese, J. Am. Chem. Soc.
1989, 111, 1698–1719.
a) B. Chaudret, F. Jalón, M. Perez-Manrique, F. Lahoz, F. J.
Plou, R. Sanchez-Delgado, New J. Chem. 1990, 14, 331–338;
b) B. Chaudret, F. A. Jalon, J. Chem. Soc., Chem. Commun.
1988, 711–713.
32.0 [CH(CH3)2], 70.3 (CH), 70.4 (C, Cp*), 106 (C, C6H3iPr3) ppm.
C25H39Cl3Ru2 (648.1): calcd. C 46.33, H 6.07; found C 46.30, H
6.13.
[4]
[5]
[6]
Exchange Reactions: Complex 10 (5.5 mg, 8.6 µmol) was dissolved
1
in CD2Cl2 (500 µL) and a H NMR spectrum of the solution was
recorded (400 MHz). A sample of complex 2 (8.7 mg, 8.6 µmol)
was analyzed in the same fashion. The two solutions were sub-
sequently mixed and immediately analyzed by 1H NMR spec-
troscopy (400 MHz).
[7]
Synthesis of Complex 12: Complex 8 (15.0 mg, 25.8 µmol) was dis-
solved in benzene (2 mL). The resulting mixture was allowed to
react for 2 h, after which small crystals of complex 12 could already
be observed. Slow addition of hexane (5 mL) by diffusion over 12 h
resulted in the formation of crystalline 12, which was isolated by
filtration. Isolated yield: 12.5 mg (73%). The reaction was quantita-
[8]
1
tive, as evidenced by H NMR analysis of the remaining solution.
1H NMR (400 MHz, CD2Cl2): δ = 1.57, 2.07 (Cp*), 6.05 (benzene)
ppm. 13C NMR (101 MHz, CD2Cl2): δ = 9.4, 11.3 (CH3, Cp*),
[9]
1
87.7 (benzene), 94.4 (d, JC–Rh = 14 Hz, C, Cp*Rh), 97.1 (C,
Cp*Ru) ppm. C26H36Cl3RhRu (658.9): calcd. C 47.39, H 5.51;
found C 47.55, H 5.12.
X-ray Crystallography: Details of the crystals and their structure
refinement are listed in Table 1; relevant geometrical parameters
are given in the respective figure captions. Data collection was per-
formed at 140(2) K on a four-circle goniometer having kappa ge-
ometry and equipped with an Oxford Diffraction KM4 Sapphire
CCD (9) or a mar345 imaging plate detector (7 and 12). Data re-
duction was carried out with CrysAlis RED, release 1.7.0.[31] An
absorption correction was applied to all data sets. Structure solu-
tion and refinement were performed with the SHELXTL software
package, release 5.1.[32] The structures were refined using the full-
matrix least-squares on F2 with all non-H atoms anisotropically
defined. H atoms were placed in calculated positions using the “ri-
ding model”.
[10]
[11]
[12]
[13]
[14]
[15]
CCDC-279177 to -279179 contain the supplementary crystallo-
graphic 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.
[16]
a) U. Koelle, J. Kossakowski, J. Organomet. Chem. 1989, 362,
383–398; b) U. Koelle, J. Kossakowski, J. Chem. Soc., Chem.
Commun. 1988, 549–551.
Acknowledgments
We gratefully acknowledge support by the Swiss National Science
Foundation and by the EPFL.
[17]
[18]
D. A. Tocher, M. D. Walkinshaw, Acta Crystallogr., Sect. B
1982, 38, 3083–3085.
ORTEP 3 for Windows version 1.076:L. J. Farrugia, J. Appl.
Cryst. 1997, 30, 565.
[1] a) B. de Clercq, F. Verpoort, Adv. Synth. Catal. 2002, 344, 639–
648; b) A. Fürstner, O. Guth, A. Düffels, G. Seidel, M. Liebl,
B. Gabor, R. Mynott, Chem. Eur. J. 2001, 7, 4811–4820; c)
M. T. Reetz, M. H. Becker, M. Liebl, A. Fürstner, Angew.
Chem. Int. Ed. 2000, 39, 1236–1239; d) J. G. Hamilton, U.
Frenzel, F. J. Kohl, T. Weskamp, J. J. Rooney, W. A. Herrmann,
O. Nuyken, J. Organomet. Chem. 2000, 606, 8–12; e) A.
Fürstner, A. F. Hill, M. Liebl, J. D. E. T. Wilton-Ely, Chem.
Commun. 1999, 601–602; f) T. Weskamp, F. J. Kohl, W. Hier-
inger, D. Gleich, W. Herrmann, Angew. Chem. Int. Ed. 1999,
38, 2416–2419; g) E. L. Dias, R. H. Grubbs, Organometallics
1998, 17, 2758–2767.
[2] a) S. Gauthier, R. Scopelliti, K. Severin, Organometallics 2004,
23, 3769–3771; b) A. C. da Silva, H. Piotrowski, P. Mayer, K.
Polborn, K. Severin, Eur. J. Inorg. Chem. 2001, 685–691.
[3] a) L. Quebatte, E. Solari, R. Scopelliti, K. Severin, Organome-
tallics 2005, 24, 1404–1406; b) L. Quebatte, M. Haas, E. Solari,
R. Scopelliti, Q. T. Nguyen, K. Severin, Angew. Chem. Int. Ed.
2005, 44, 1084–1088; c) L. Quebatte, R. Scopelliti, K. Severin,
[19]
[20]
U. Koelle, J. Kossakowski, Inorg. Chim. Acta 1989, 164, 23–32.
D. Amoroso, G. P. A. Yap, D. E. Fogg, Organometallics 2002,
21, 3335–3343.
T. Arthur, T. A. Stephenson, J. Organomet. Chem. 1981, 208,
369–387.
a) H. Aneetha, M. Jiménez-Tenorio, M. C. Puerta, P. Valerga,
V. N. Sapunov, R. Schmid, K. Kirchner, K. Mereiter, Organo-
metallics 2002, 21, 5334–5346; b) J. W. Kriesel, S. König, M. A.
Freitas, A. G. Marshall, J. A. Leary, T. D. Tilley, J. Am. Chem.
Soc. 1998, 120, 12207–12215; c) A. A. Dembek, P. J. Fagan,
Organometallics 1995, 14, 3741–3745; d) U. Koelle, A. Hörnig,
U. Englert, Organometallics 1994, 13, 4064–4066; e) M. D.
Ward, P. J. Fagan, J. C. Calabrese, D. C. Johnson, J. Am. Chem.
Soc. 1989, 111, 1719–1732.
[21]
[22]
[23]
[24]
A. Schmid, H. Piotrowski, T. Lindel, Eur. J. Inorg. Chem. 2003,
2255–2263.
In solution, the complex [(Cp*RhCl2)2(µ-NH2NMe2)] has been
found to be in equilibrium with the ionic species [Cp*RhCl(µ-
Eur. J. Inorg. Chem. 2006, 231–236
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
235

L. Quebatte, R. Scopelliti, K. Severin
FULL PAPER
NH2NMe2)]2+·2[Cp*RhCl3]–:W. Rigby, J. A. McCleverty, P. M. [28] M. A. Bennett, A. K. Smith, J. Chem. Soc., Dalton Trans. 1974,
Maitlis, J. Chem. Soc., Dalton Trans. 1979, 382–386.
[25] a) I. Ara, J. R. Berenguer, E. Eguizábal, J. Forniés, E. Lalinde,
A. Martín, Eur. J. Inorg. Chem. 2001, 1631–1640; b) K.
Umakoshi, K. Murata, S. Yamashita, K. Isobe, Inorg. Chim.
Acta 1991, 190, 185–191.
[26] U. Koelle, J. Kossakowski, D. Grumbine, T. D. Tilley, Inorg.
Synth. 1992, 29, 225–228.
2, 233–241.
[29] C. White, A. Yates, P. M. Maitlis, D. M. Heinekey, Inorg.
Synth. 1992, 29, 228–234.
[30] J. W. Hull, W. L. Gladfelter, Organometallics 1984, 3, 605–613.
[31] Oxford Diffraction Ltd., Abingdon, Oxfordshire, UK, 2003.
[32] G. M. Sheldrick, University of Göttingen, Germany, 1997;
Bruker AXS, Inc., Madison, Wisconsin, 53719, USA, 1997.
Received: August 2, 2005
[27] M. A. Bennett, T. N. Huang, T. W. Matheson, A. K. Smith, In-
org. Synth. 1982, 21, 74–78.
Published Online: November 21, 2005
236
www.eurjic.org
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2006, 231–236