Atom transfer radical additions with the cationic half-sandwich complex [Cp*Ru(PPh3)2(CH3CN)]OTf

Article abstract of DOI:10.1002/ejic.200500321

The cationic ruthenium half-sandwich complex [Cp*Ru(PPh ₃)₂(CH₃CN)][OTf] (2) (Cp* = η⁵-C₅Me₅, OTf = SO₃CF ₃) was synthesized by reduction of [Cp*RuCl₂] ₂ with zinc in the presence of NaOTf and subsequent reaction with PPh₃. When NaOTf was omitted, the corresponding tetrachlorozincate salts were obtained. Complex 2, as well as the salts [Cp*Ru(CH ₃CN)₃]₂[ZnCl₄] (3) and [Cp*Ru(PPh₃)₂-(CH₃CN)] ₂[ZnCl₄] (4), were characterized by single-crystal X-ray analysis. Complex 2 proved to be a potent catalyst for the atom transfer radical addition of CCl₄ and CHCl₃ to terminal olefins, displaying a performance superior to that of the previously described neutral catalyst [Cp*RuCl(PPh₃)₂]. For the addition of CHCl₃ to styrene, a total turnover number of 890 was achieved. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.

Full text of DOI:10.1002/ejic.200500321

FULL PAPER
Atom Transfer Radical Additions with the Cationic Half-Sandwich Complex
[Cp*Ru(PPh3)2(CH3CN)]OTf
Laurent Quebatte,[a] Rosario Scopelliti,[a][‡] and Kay Severin*[a]
Keywords: ATRA reaction / Homogeneous catalysis / Radical reaction / Ruthenium
The
cationic
ruthenium
half-sandwich
complex
X-ray analysis. Complex 2 proved to be a potent catalyst for
the atom transfer radical addition of CCl4 and CHCl3 to ter-
minal olefins, displaying a performance superior to that of
the previously described neutral catalyst [Cp*RuCl(PPh3)2].
For the addition of CHCl3 to styrene, a total turnover number
of 890 was achieved.
[Cp*Ru(PPh3)2(CH3CN)][OTf] (2) (Cp* = η5-C5Me5, OTf =
SO3CF3) was synthesized by reduction of [Cp*RuCl2]2 with
zinc in the presence of NaOTf and subsequent reaction with
PPh3. When NaOTf was omitted, the corresponding tetra-
chlorozincate salts were obtained. Complex 2, as well as the
salts [Cp*Ru(CH3CN)3]2[ZnCl4] (3) and [Cp*Ru(PPh3)2-
(CH3CN)]2[ZnCl4] (4), were characterized by single-crystal
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2005)
potent catalyst for ATRA reactions. Its stability is signifi-
cantly higher than that of the neutral counterpart 1. Conse-
quently, good turnover numbers (TONs) were observed,
even for “difficult” reactions such as the addition of CHCl3
to styrene.
Introduction
The atom transfer radical addition (ATRA) of polyhalo-
genated compounds to olefins (“Kharasch reaction”)[1] is a
versatile method for C–C bond formation and has found
several applications in organic synthesis.[2] In 1973, it was
reported that the complex [RuCl2(PPh3)3] is able to ef-
ficiently catalyze this type of reaction and it was sub-
sequently used as the catalyst of choice for more than 20
years.[3] Over the last 6 years, however, several new ruthe-
nium-based catalysts with superior performance have been
reported.[4] Among these, the complex [Cp*RuCl(PPh3)2]
(1) is of special interest since it is one of the few catalysts,
which allows to carry out the addition of CCl4 and CHCl3
to olefins at ambient temperatures.[5,6] Despite its high ac-
tivity, complex 1 suffers from poor long term stability, a
characteristic shared by many other highly active catalysts
for the Kharasch reaction.[4]
Results and Discussion
Cationic complexes of the general formula [Cp*Ru-
(PR3)2(CH3CN)]X (X– = weakly coordinating anion) have
been obtained by reaction of complex 1 with MX in aceto-
+ [11]
nitrile (M+
=
Ag+, NH4
)
or by reaction of
[Cp*Ru(CH3CN)3]X with PR3 in CH2Cl2 (Scheme 1).[12]
For the synthesis of the complex [Cp*Ru(PPh3)2-
(CH3CN)][OTf] (2), we decided to use the latter pathway
since the trisacetonitrile complex [Cp*Ru(CH3CN)3]X is
easily accessible by reduction of [Cp*RhCl2]n with zinc in
acetonitrile in the presence of MX salts.[12]
Nagashima et al. have reported that the ATRA activity
of the dinuclear complex [Cp*Ru{μ2-iPrN=C(Me)-
NiPr}RuClCp*] could be increased by transforming it into
a cationic species using NaPF6 or NaBPh4.[7] Similarly, the
activity of ruthenium chloro catalysts for the closely related
atom transfer radical polymerization (ATRP)[8] could be
enhanced by chloride abstraction with silver salts.[9] For Ru
vinylidene catalysts, on the other hand, it was reported that
the abstraction of a chloro ligand lead to a decrease in
ATRA activity.[10] In the following we show that the cat-
ionic complex [Cp*Ru(PPh3)2(CH3CN)][OTf] (2) is a very
[a] Institut de Sciences et Ingénierie Chimiques, École Polytech-
nique Fédérale de Lausanne (EPFL)
1015 Lausanne, Switzerland
Scheme 1. Synthesis of cationic complexes of the general formula
[Cp*Ru(PR3)2(CH3CN)]X (X– = weakly coordinating anion).
Fax: +41-21-693-9305
Following this synthetic route it was possible to prepare
the cationic complex 2 in 95% yield by reaction of
E-mail: kay.severin@epfl.ch
[‡] X-ray structural analysis.
Eur. J. Inorg. Chem. 2005, 3353–3358
DOI: 10.1002/ejic.200500321
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3353

L. Quebatte, R. Scopelliti, K. Severin
FULL PAPER
[Cp*RuCl2]2 with zinc in acetonitrile in the presence of Na-
OTf and direct conversion of the product with two equiva-
lents of PPh3 (Scheme 2). Complex 2 displays a good solu-
bility in polar organic solvents such as THF, dichlorometh-
ane and chloroform, and a moderate solubility in toluene.
The identity of 2 was confirmed by NMR spectroscopy, ele-
mental analysis and single-crystal X-ray analysis (Figure 1).
Scheme 2. Synthesis of complex 2.
Scheme 3. Synthesis of the tetrachlorozincate complex 3 and its
reaction with PPh3.
Figure 2. ORTEP[13] drawing of the molecular structure of 3 in the
crystal. The hydrogen atoms are omitted for clarity. Selected bond
lengths [Å] and angles [°]: Ru1–N1 2.095(2), Ru1–N2 2.108(2),
Ru1–N3 2.103(2), Ru2–N4 2.110(2), Ru2–N5 2.102(2), Ru2–N6
2.109(2); N1–Ru1–N2 88.19(8), N1–Ru1–N3 84.67(8), N3–Ru1–N2
90.60(7), N5–Ru2–N4 90.84(8), N5–Ru2–N6 91.66(8), N–Ru2–N4
81.76(8).
Figure 1. ORTEP[22] drawing of the molecular structure of 2 in the
crystal. The OTf– anion and the hydrogen atoms are omitted for
clarity. Selected bond lengths [Å] and angles [°]: Ru1–N1 2.056(2),
Ru1–P1 2.3709(6), Ru1–P2 2.3462(7); P2–Ru1–P1 99.41(2), N1–
Ru1–P1 87.97(5), N1–Ru1–P2 87.95(6).
The cation of complex 2 displays the expected piano-
stool geometry. As a consequence of the steric demand of
the triphenylphosphane ligands, the P–Ru–P angle
[99.41(2)°] is larger than the N–Ru–P angles [N1–Ru1–P1
87.97(5)°; N1–Ru1–P2 87.95(6)°]. The Ru–P bond lengths
[Ru1–P1 2.3709(6) Å, Ru1–P2 2.3462(7) Å] are similar to
what has been found for the neutral complex 1.[13]
In order to investigate the influence of the NaOTf salt
during the synthesis of complex 2, we have performed the
reduction of [Cp*RuCl2]2 with zinc in acetonitrile in the
absence of this salt. The formation of a trisacetonitrile com-
plex [Cp*Ru(CH3CN)3]+ (3) was observed but as the coun-
terion, the tetrachlorozincate anion was formed as revealed
by single-crystal X-ray analysis (Scheme 3, Figure 2). Com-
plex 3 proved to be not suited for a clean synthesis of a
bis(triphenylphosphane) adduct: when two equivalents of
PPh3 were added to a solution of 3 in CD2Cl2, the desired
cationic bisadduct 4 was formed but along with the neutral
Figure 3. ORTEP[13] drawing of the molecular structure of 4 in the
crystal. The hydrogen atoms and the solvent molecules
(3×CH2Cl2) are omitted for clarity. Selected bond lengths [Å] and
angles [°]:Ru1–N1 2.037(6), Ru1–P1 2.3568(19), Ru1–P2 2.343(2),
Ru2–N2 2.061(7), Ru2–P3 2.3556(19), Ru2–P4 2.346(2); N1–Ru1–
P1 87.44(16), N1–Ru1–P2 88.12(18), P2–Ru1–P1 99.00(7), N2–
Ru2–P4 89.28(18), N2–Ru2–P3 90.17(17), P4–Ru2–P3 97.19(7).
complex 1, the monoadduct 5,[14,15] and free PPh3 as evi-
The bond lengths and angles found for the two crytallo-
1
denced by H and 31P NMR spectroscopy. From this mix- graphically independent cations of complex 3 are very sim-
ture, it was possible to obtain single crystals of complex ilar to those observed for other [Cp*Ru(CH3CN)3]+ com-
4 by addition of pentane. A graphic representation of the plexes.[16] The N–Ru–N angles are close to 90°. The geome-
structure of 4 is depicted in Figure 3.
try of the cations can thus be described as pseudo-octahe-
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Atom-Transfer Radical Additions
FULL PAPER
dral with the Cp* ligand occupying three facial coordina-
tion sites. As it was observed for complex 2, the P–Ru–P
angles of 4 [99.00(7) and 97.19(7)°] are larger than the P–
Ru–N angles [P–Ru–N 87.44(16)–90.17(17)°].
To evaluate the ability of the cationic complex 2 to cata-
lyze ATRA reactions, we first investigated the addition of
CCl4 to styrene at 60 °C using a molar ratio of 2/styrene/
CCl4 = 1:300:432. The complete conversion of the olefin
was observed within 2 h. For the neutral complex 1, a con-
version of 97% was reported after 5 h.[5] In order to obtain
more information about differences in activity and stability
of the catalysts 1 and 2, we have investigated the time course
of the reaction between styrene and CCl4 at room tempera-
ture in chloroform with a molar ratio of Ru/styrene/CCl4 =
1:300:600 (Figure 4). For reactions with the cationic catalyst
2, a quantitative reaction was observed after ca. 4 h. For
reactions catalyzed by the neutral complex 1, on the other
hand, a very fast product formation was found for the first
20 min, but then the rates dropped dramatically and the
conversion reached a plateau at around 40%. When the sol-
vent was changed to toluene and the CCl4 concentration
was reduced, an increased lifetime of the catalyst was ob-
served but still the final conversion (60%) was lower than
what was found for 2. This data suggested that the neutral
catalyst 1 shows a higher intrinsic activity than the cationic
complex 2 but a significantly lower stability. This is in
agreement with the observation of Simal et al. that complex
1 rapidly decomposed in presence of CCl4: when 10 equiva-
lents of CCl4 were added to a solution of 1 in toluene at
20 °C, the complete conversion into a paramagnetic RuIII
compound occurred within 2 h.[5] When a similar experi-
ment was performed with the cationic complex 2, only 40%
decomposition was observed after 2 h. For complex 1 it was
suggested that PPh3 dissociation is required to activate the
catalyst.[5] This step is likely to be faster for the neutral
complex 1 as compared to the cationic complex 2, which
may explain the higher initial activity of the former. The
higher stability of the cationic complex 2, on the other
hand, may be due to a different activity of the RuIII species
formed by atom transfer but further investigations are
needed to clarify this point.
Figure 4. Time course of the reaction between styrene and CCl4
catalyzed by complexes 1 (᭺) or 2 (᭹). Reaction conditions: Ru/
styrene/CCl4 = 1:300:600; solvent = CDCl3; [Ru] = 4.6 mm; 24 °C.
The yield is based on the formation of the product as determined
1
by H NMR spectroscopy.
Table 1. ATRA reactions catalyzed by complex 2.[a]
Entry Olefin
CXCl3
T
t
Conv. Yield
[°C] [h]
[%]
[%]
1
2
3
4
5
6
7
8
9
styrene
CCl4
24
24
24
40
5
2
100
100
98
80
96
95
96
96
99
97
93
67
77
88
92
90
33
15
methyl methacrylate CCl4
n-butyl acrylate
1-decene
styrene
p-chlorostyrene
p-methoxystyrene
CCl4
CCl4
CHCl3 40
CHCl3 40
CHCl3 40
10
24
24
48
48
24
24
methyl methacrylate CHCl3 40
n-butyl acrylate CHCl3 40
[a] Reaction conditions: 2/olefin/CCl4 = 1:300:600, [2] = 4.6 mm,
solvent: CHCl3 or 2/olefin/CHCl3 = 1:100, [2] = 13.8 mm, solvent
= CHCl3. The conversion is based on the consumption of the olefin
and the yield is based on the formation of the product as deter-
1
mined by GC or H NMR spectroscopy after the time given.
The good performance of the cationic catalyst 2 was con-
firmed in other ATRA reactions (Table 1). As mentioned
above, the reaction between styrene and CCl4 could be com-
pleted within 5 h using 0.33 mol% of complex 2 at room
temperature (entry 1). Using only 0.02 mol% catalyst, a to-
tal TON of 3050 was measured after 5 weeks.[17] A remark-
ably fast and clean reaction was observed with methyl
methacrylate (MMA) and CCl4 as the substrates (entry 2).
After 2 h at room temperature, a yield of 93% was ob-
tained. For the neutral catalyst 1, for comparison, a yield
of only 36% was found after 24 h.[5] The olefins n-butyl
acrylate (entry 3) and 1-decene (entry 4) gave lower yields
of 67 and 77%, respectively. For the former substrate, this
was due to competing oligomerization reactions.
mol% was employed (entries 5–9). Under these conditions,
catalyst 2 provided the chloroform adducts of the aromatic
olefins styrene, p-chlorostyrene, and p-methoxystyrene with
good yields (entries 5–7). A TON of 890 was obtained for
the addition of CHCl3 to styrene using 0.1 mol% of com-
plex 2. This is – to the best of our knowledge – the highest
value ever reported for a ruthenium-based catalyst. For ac-
rylate substrates, almost complete conversions were deter-
mined after 24 h. The yields of the desired addition prod-
ucts, however, were very modest due to competing polyme-
rization reactions (entries 8 and 9).
Conclusions
In order to perform ATRA reactions with the signifi-
cantly less active substrate CHCl3, the reaction temperature
Over the last few years, several highly active ruthenium-
was increased to 40 °C and a catalyst concentration of 1 based catalysts for ATRA reactions have been described.[4]
Eur. J. Inorg. Chem. 2005, 3353–3358
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© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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L. Quebatte, R. Scopelliti, K. Severin
FULL PAPER
tion of the solvent under vacuum, the resulting powder was sus-
pended in Et2O (15 mL), isolated by filtration, washed with ad-
ditional Et2O (15 mL) and dried under vacuum. Yield: 1030 mg
(93%). Single crystals were obtained by slow diffusion of Et2O into
a solution of 3 in CH3CN. 1H NMR (400 MHz, CD3CN): δ = 1.59
(s, 15 H, Cp*) ppm. 13C NMR (101 MHz, CD3CN): δ = 9.7 (CH3,
Cp*), 80.6 (C, Cp*) ppm. Elemental analysis: calcd. (%) for
C32H48Cl4N6Ru2Zn×3/4 CH3CN (956.9): C 42.05, H 5.29, N 9.88;
found: C 42.36, H 5.36, N 9.47.
These catalysts allow to perform Kharasch reactions under
very mild conditions with few side products. But still, there
are some important challenges that need to be addressed by
future research in this area. First of all, the mechanistic
understanding of ruthenium-catalyzed ATRA reactions is
rudimentary which hampers a more rational approach
towards catalyst discovery (e.g. stereoselective catalysts) and
optimization. Furthermore, catalyst stability is a problem
for several of the newly developed complexes and apart
from optimizing the reaction conditions (temperature, con-
centrations etc.), solutions to this dilemma are not evident.
The results described above demonstrate that a simple
modification such as the conversion of a chloro complex
into a cationic acetonitrile complex may result in a signifi-
cantly increased catalyst stability. Although it remains to
be seen whether similar effects can be observed for other
catalysts, it seems worthwhile to consider modifications of
this type in future investigations.
Reaction of Complex 3 with PPh3: PPh3 (5.7 mg, 21.7 μmol) was
added to a solution of complex 3 (5.0 mg, 5.4 μmol) in CD2Cl2
(500 μL). The resulting bright orange solution was analyzed by 1H
and 31P NMR spectroscopy. Single crystals of 4 were obtained by
slow diffusion of pentane into the reaction mixture. NMR [400
(1H), 162 (31P) MHz, aromatic protons, free CH3CN and PPh3 are
4
omitted]: 4: 1H: δ = 1.13 (t, JH,P = 1.6 Hz, 15 H, Cp*), 2.87 (t,
1
5JH,P = 1.4 Hz, 3 H, CH3CN) ppm. 31P: δ = 43.0 ppm. 1: H: δ =
4
1
1.01 (t, JH,P = 1.4 Hz, 15 H, Cp*) ppm. 31P: δ = 41.0 ppm. 5: H:
4
5
δ = 1.42 (d, JH,P = 1.6 Hz, 15 H, Cp*), 2.22 (d, JH,P = 1.2 Hz, 6
H, CH3CN) ppm. 31P: δ = 48.9 ppm.
General Procedure for the ATRA of CCl4 to Olefins: 1000 μL of a
CDCl3 stock solution of the olefin, CCl4, and the internal standard
mesitylene were added to a 1.5 mL vial containing the solid catalyst
2 (final conc.: [2] = 4.6 mm, [olefin] = 1.38 m, [CCl4] = 2.76 m, [me-
sitylene] = 0.36 m). For 1-decene, the resulting solution was placed
in an oil bath tempered at 40 °C. After the given time, a sample
(20 μL) was removed from the reaction mixture, diluted with
CDCl3 (550 μL) and analyzed by 1H NMR spectroscopy or gas
chromatography. The kinetic experiments were performed in an
analogous fashion by removing several samples at regular time in-
tervals.
Experimental Section
General: All reactions were performed under a dry dinitrogen at-
mosphere. The solvents and substrates were distilled from appropri-
ate drying agents and stored under dinitrogen. Zn dust (Ͻ 10 mi-
cron; 98+%) was obtained from Aldrich, NaOTf (97+%) and
PPh3 (98.5+%) were obtained from Fluka. The complexes
[18]
[Cp*RuCl2]2 and [Cp*RuCl(PPh3)2][19] were prepared according
to literature procedures. The H, 13C, and 31P NMR spectra were
1
recorded on a Bruker Advance DPX 400 spectrometer with the
solvents as internal standards (1H, 13C) or a solution of H3PO4 in
D2O as external standard (31P). All spectra were recorded at room
temperature. GC-MS analyses were performed with a WCOT
Fused Silica column (30 m) coupled to a Varian Saturn 2200 mass
spectrometer.
General Procedure for the ATRA of CHCl3 to Olefins: 500 μL of a
CDCl3 stock solution of the olefin and the internal standard mesit-
ylene were added to a 1.5 mL vial containing the solid catalyst 2
(final conc.: [2] = 13.8 mm, [olefin] = 1.38 m, [mesitylene] = 0.36 m).
The resulting solution was placed in an oil bath tempered at 40 °C.
After the given time, a sample (20 μL) was removed from the reac-
tion mixture, diluted with CDCl3 (550 μL) and analyzed by 1H
NMR spectroscopy or gas chromatography.
Synthesis of Complex 2: Zn (0.2 g, 3.1 mmol) and NaOTf (84 mg,
488 μmol) were added to a solution of [Cp*RuCl2]2 (100 mg, 162
μmol) in CH3CN (5 mL) and the mixture was stirred for 2 h at
room temperature. The yellow solution was filtered and the remain-
ing Zn was washed with additional solvent (2×3 mL). After evapo-
ration of the solvent, the resulting powder was dissolved in CH2Cl2
(5 mL), filtered, and the filtrate was washed with additional
CH2Cl2 (2×3 mL). PPh3 (256 mg, 976 μmol) was added to the
combined solutions whilst stirring. After for 20 min, the mixture
was concentrated to 2 mL and poured into a flask containing hex-
ane (15 mL) to precipitate the product as a yellow powder, which
was isolated by filtration, washed with hexane (2×3 mL), and dried
under vacuum. Yield: 294 mg (95%). Single crystals were obtained
Decomposition Experiment: Complex 2 (2.8 mg, 2.9 μmol) and CCl4
(2.9 μL, 30.1 μmol) were dissolved in CD2Cl2 (500 μL). The reac-
tion followed by 1H and 31P NMR (400 and 162 MHz, respectively)
for 10 h at 21 °C.
X-ray Crystallography: Details about the crystals and their struc-
ture refinement are listed in Table 2 and Table 3 whereas some rel-
evant geometrical parameters are included into the picture cap-
tions. Data collection were performed at 140(2) K on a 4-circle go-
niometer having kappa geometry and equipped with an Oxford
Diffraction KM4 Sapphire CCD. Data reduction was carried out
with CrysAlis RED, release 1.7.0.[20] Absorption correction has
been applied to all data sets. Structure solution and refinement
were performed with the SHELXTL software package, release
5.1.[21] 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 “riding model”.
CCDC-268907–268909 contain the supplementary crystallographic
data for this paper. These data can be obtained free of charge
from The Cambridge Crystallographic Data Centre via
1
by diffusion of pentane into a solution of 2 in CH2Cl2. H NMR
4
(400 MHz, CD2Cl2): δ = 1.13 (t, JH,P = 1.6 Hz, 15 H, Cp*), 2.65
5
(t, JH,P = 0.6 Hz, 3 H, CH3CN), 7.13–7.46 (m, 30 H, Ph) ppm.
13C NMR (101 MHz, CD2Cl2): δ = 5.9 (CH3CN), 9.7 (CH3, Cp*),
93.1 (C, Cp*), 128.2–134.2 (Ph), 129.3 (CH3CN) ppm. 31P NMR
(162 MHz, CD2Cl2): δ = 42.20 ppm. Elemental analysis: calcd. (%)
for C49H48F3NO3P2RuS × H2O (969.0): C 60.73, H 5.20, N 1.45;
found C 60.84, H 5.17, N 1.56.
Synthesis of Complex 3: A solution of [Cp*RuCl2]2 (736 mg, 1196
μmol) in CH3CN (35 mL) was added Zn (5.0 g, 76.5 mmol) and
stirred for 5 h at room temperature. The initial dark brown color
changed to bright yellow. The solution was filtered and the remain-
ing Zn was washed with additional solvent (15 mL). After evapora- www.ccdc.cam.ac.uk/data_request/cif.
3356 © 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim www.eurjic.org
Eur. J. Inorg. Chem. 2005, 3353–3358

Atom-Transfer Radical Additions
FULL PAPER
Table 2. Crystallographic data for the complexes 2 and 3.
2
3
Empirical formula
Molecular weight [gmol–1]
Crystal size
Crystal system
Space group
C49H48F3NO3P2RuS
950.95
C32H48Cl4N6Ru2Zn
926.07
0.16×0.13×0.11
triclinic
0.18×0.13×0.09
triclinic
¯
P1
¯
P1
a [Å]
b [Å]
10.5409(4)
13.3793(7)
9.3648(4)
12.9800(8)
c [Å]
α [°]
16.2230(9)
88.977(4)
18.3753(10)
72.891(5)
β [°]
86.567(4)
75.659(4)
2212.64(18)
2
1.427
140(2)
0.529
3.12 to 25.03
–10 Ǟ 10, –15 Ǟ 15, –19 Ǟ 19
13077
6823 (Rint = 0.0200)
semi-empirical
0.9638 and 0.8015
6823/0/541
88.514(4)
72.566(5)
2031.94(18)
2
1.514
140(2)
1.611
3.15 to 25.03
–10 Ǟ 11, –15 Ǟ 15, –21 Ǟ 20
12149
6273 (Rint = 0.0225)
empirical
0.887 and 0.620
6273/0/406
0.985
γ [°]
Volume [Å3]
Z
Density [g cm–3]
Temperature [K]
Absorption coefficient [mm–1]
Θ range [°]
Index ranges
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 [e·Å–3]
1.044
R1 = 0.0307, wR2 = 0.0799
R1 = 0.0340, wR2 = 0.0822
0.653 and –0.810
R1 = 0.0219, wR2 = 0.0567
R1 = 0.0265, wR2 = 0.0581
0.466 and –0.675
Table 3. Crystallographic data for the complex 4.
4×3CH2Cl2
[1]
[2]
[3]
[4]
M. S. Kharasch, E. V. Jensen, W. H. Urry, Science 1945, 102,
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hedron Lett. 2000, 41, 6071; b) F. Simal, L. Wlodarczak, A.
Demonceau, A. F. Noels, Eur. J. Org. Chem. 2001, 14, 2689.
For other complexes, which catalyze ATRA reactions under
mild conditions see a) L. Quebatte, E. Solaris, R. Scopelliti, K.
Severin, Organometallics 2005, 24, 1404; b) L. Quebatte, M.
Haas, E. Solari, R. Scopelliti, Q. T. Nguyen, K. Severin, An-
gew. Chem. Int. Ed. 2005, 44, 1084; c) L. Quebatte, R. Scopel-
liti, K. Severin, Angew. Chem. Int. Ed. 2004, 43, 1520; d) O.
Tutusaus, S. Delfosse, A. Demonceau, A. F. Noels, C. Vinas, F.
Teixidor, Tetrahedron Lett. 2003, 44, 8421; e) O. Tutusaus, C.
Vinas, R. Nunez, F. Teixidor, A. Demonceau, S. Delfosse, A. F.
Noels, I. Mata, E. Molins, J. Am. Chem. Soc. 2003, 125, 11830.
Y. Motoyama, M. Gondo, S. Masuda, Y. Iwashita, H. Nagash-
ima, Chem. Lett. 2004, 33, 442.
Empirical formula
Molecular weight [gmol–1]
Crystal size
Crystal system
Space group
C99H102Cl10N2P4Ru2Zn
2065.72
0.22×0.20×0.11
monoclinic
P21
a [Å]
b [Å]
10.6258(4)
21.7283(11)
c [Å]
α [°]
20.4384(11)
90
[5]
[6]
β [°]
90.815(4)
90
4718.3(4)
γ [°]
Volume [Å3]
Z
2
Density [g cm–3]
Temperature [K]
Absorption coefficient [mm–1]
Θ range [°]
1.454
140(2)
0.966
2.99 to 25.03
Index ranges
–11 Ǟ 10, –25 Ǟ 25, –24 Ǟ 24
27665
15206 (Rint = 0.0498)
empirical
0.823 and 0.458
15206/1/1063
0.923
R1 = 0.0517, wR2 = 0.1063
R1 = 0.0715, wR2 = 0.1135
1.158 and –0.707
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 [e·Å–3]
[7]
[8]
[9]
M. Kamigaito, T. Ando, M. Sawamoto, Chem. Rev. 2001, 101,
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[10]
[11]
Acknowledgments
We gratefully acknowledge support by the Swiss National Science
Foundation and by the EPFL.
[12]
B. Steinmetz, W. A. Schenk, Organometallics 1999, 18, 943.
Eur. J. Inorg. Chem. 2005, 3353–3358
www.eurjic.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3357

L. Quebatte, R. Scopelliti, K. Severin
FULL PAPER
[13] I. A. Guzei, M. A. Paz-Sandoval, R. Torres-Lubian, P. Juarez-
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[14] A. A. Zlota, M. Tilset, K. G. Caulton, Inorg. Chem. 1993, 32,
3816.
[15] When complex 2 is dissolved in CD3CN, the formation of the
monotriphenylphosphane adduct can be observed by NMR
spectroscopy.
[16] a) M. J. Burk, A. J. Arduengo III, J. C. Calabresem, R. L. Har-
low, J. Am. Chem. Soc. 1989, 111, 8938; b) C. Gemel, A. LaP-
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[18] U. Koelle, J. Kossakowski, D. Grumbine, T. D. Tilley, Inorg.
Synth. 1992, 29, 225.
[19] M. S. Chinn, D. M. Heinekey, J. Am. Chem. Soc. 1990, 112,
5166.
[20] Oxford Diffraction Ltd., Abingdon, Oxfordshire, UK, 2003.
[21] G. M. Sheldrick, University of Göttingen, Germany, 1997;
Bruker AXS, Inc., Madison, Wisconsin, 53719, USA, 1997.
[22] ORTEP 3 for Windows version 1.076. L. J. Farrugia, J. Appl.
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Received: April 18, 2005
Published Online: July 7, 2005
[17] Reaction conditions: 2/styrene/CCl4 = 1:5000:7500; solvent:
[D8]toluene. [2] = 0.28 mm; 24 °C.
3358
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2005, 3353–3358