Versatile Ru-based metathesis catalysts designed for both homogeneous and heterogeneous processes

Article abstract of DOI:10.1016/j.jorganchem.2006.08.019

The synthesis of new ruthenium-based catalysts applicable for both homogeneous and heterogeneous metathesis is described. Starting from the Hoveyda-Grubbs first generation (1) and the Hoveyda-Grubbs second generation (2) catalysts the homogeneous catalysts [RuCl((RO)₃Si-C₃H₆-N(R′)-CO-C₃F₆-COO)({double bond, long}CH-o-O-iPr-C₆H₄)(SIMes)] (4: R = Et, R′ = H; 5: R = R′ = Me) (SIMes = 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene) were prepared by substitution of one chloride ligand with trialkoxysilyl functionalized silver carboxylates (RO)₃Si-C₃H₆-N(R′)-CO-C₃F₆-COOAg (3a: R = Et, R′ = H; 3b: R = R′ = Me). These homogeneous ruthenium-species are among a few known examples with mixed anionic ligands. Exchange of both chloride ligands afforded the catalysts [Ru((RO)₃Si-C₃H₆-N(R′)-CO-C₃F₆-COO)({double bond, long}CH-o-O-iPr-C₆H₄)(SIMes)] (9: R = Et, R′ = H; 11: R = R′ = Me) and [Ru((RO)₃Si-C₃H₆-N(R′)-CO-C₃F₆-COO)({double bond, long}CH-o-O-iPr-C₆H₄)(PCy₃)] (8: R = Et, R′ = H; 10: R = R′ = Me). The reactivity of the new complexes was tested in homogeneous ring-closing metathesis (RCM) of N,N-diallyl-p-toluenesulfonamide and TONs of up to 5000 were achieved. Heterogeneous catalysts were obtained by reaction of 4, 5 and 8-11 with silica gel (SG-60). The resultant supported catalysts 4a, 5a, 8a-11a showed reduced activity compared to their homogenous analogues, but rival the activity of similar heterogeneous systems.

Full text of DOI:10.1016/j.jorganchem.2006.08.019

Journal of Organometallic Chemistry 691 (2006) 5267–5277
www.elsevier.com/locate/jorganchem
Versatile Ru-based metathesis catalysts designed for both
homogeneous and heterogeneous processes
a
a,
*
Kati Vehlow a,b, Simon Maechling , Katrin Ko¨hler b,1, Siegfried Blechert
a
Technische Universita¨t Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany
b
Merck KGaA, Frankfurter Strasse 250, D-64293 Darmstadt, Germany
Received 28 June 2006; received in revised form 9 August 2006; accepted 9 August 2006
Available online 18 August 2006
Abstract
The synthesis of new ruthenium-based catalysts applicable for both homogeneous and heterogeneous metathesis is described. Starting
from the Hoveyda-Grubbs first generation (1) and the Hoveyda-Grubbs second generation (2) catalysts the homogeneous catalysts
[RuCl((RO)3Si–C3H6–N(R0)–CO–C3F6–COO)(@CH–o-O–iPr–C6H4)(SIMes)] (4: R = Et, R0 = H; 5: R = R0 = Me) (SIMes = 1,3-
bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene) were prepared by substitution of one chloride ligand with trialkoxysilyl func-
tionalized silver carboxylates (RO)3Si–C3H6–N(R0)–CO–C3F6–COOAg (3a: R = Et, R0 = H; 3b: R = R0 = Me). These homogeneous
ruthenium-species are among a few known examples with mixed anionic ligands. Exchange of both chloride ligands afforded the catalysts
[Ru((RO)3Si–C3H6–N(R0)–CO–C3F6–COO)(@CH–o-O–iPr–C6H4)(SIMes)] (9: R = Et, R0 = H; 11: R = R0 = Me) and [Ru((RO)3Si–
C3H6–N(R0)–CO–C3F6–COO)(@CH–o-O–iPr–C6H4)(PCy3)] (8: R = Et, R0 = H; 10: R = R0 = Me). The reactivity of the new complexes
was tested in homogeneous ring-closing metathesis (RCM) of N,N-diallyl-p-toluenesulfonamide and TONs of up to 5000 were achieved.
Heterogeneous catalysts were obtained by reaction of 4, 5 and 8–11 with silica gel (SG-60). The resultant supported catalysts 4a, 5a, 8a–
11a showed reduced activity compared to their homogenous analogues, but rival the activity of similar heterogeneous systems.
Ó 2006 Elsevier B.V. All rights reserved.
Keywords: Heterogeneous catalysis; Homogeneous catalysis; Metathesis; Ruthenium; Supported catalysts; Silica gel
1. Introduction
sons for this interest [3]. There are three general methods
for attachment to the solid support: (a) through the alky-
lidene moiety (R), (b) through the permanently bound
ancillary ligand (L) and (c) through the anionic ligand
(X) bound directly to the Ru metal [4] (Scheme 1).
Metal-catalyzed olefin metathesis has become estab-
lished as a powerful tool for carbon–carbon bond forma-
tion in organic chemistry [1]. In particular, ruthenium
alkylidenes have been of special interest as olefin metathesis
catalysts since they possess significant advantages in terms
of stability, ease of storage and handling [2]. In recent years
there has been an increased demand for supported versions
of modern catalysts. Reduction of metal contamination,
possibility of catalyst recovery, access to high-throughput
chemistry and continuous flow reactors are only some rea-
The most versatile and widely used method of attach-
ment has been through the alkylidene moiety (R), due to
the relative ease of their preparation and the several
attempts to combine the advantages of homogeneous and
heterogeneous catalysts into a single manifold [5]. During
the metathesis reaction, the catalyst is released from the
solid support, and the active species is solubilized. This is
one of the reasons why this type of solid supported catalyst
has activities comparable to homogenous catalysts. How-
ever, for this method to be viable as a solid support tech-
nology, the propagating species must return to the solid
support at the end of the sequence, which often is difficult
to achieve. Attachment of the catalyst through both the
*
Corresponding author. Fax: +493031423619.
E-mail addresses: katrin.koehler@sartorius.com (K. Ko¨hler),
blechert@chem.tu-berlin.de (S. Blechert).
1
Sartorius AG, Weender Landstrasse 94-108, D-37075 Go¨ttingen,
Germany. Fax: +49 5513082510.
0022-328X/$ - see front matter Ó 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.08.019

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K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
L1
2. Results and discussion
X
X
Ru
L2
2.1. Synthesis of the homogeneous Ru complexes
R
The required trialkoxysilyl-functionalized silver(I) car-
boxylate (EtO)3Si–C3H6–NH–CO–C3F6–COOAg (3a) and
(MeO)3Si–C3H6–N(Me)–CO–C3F6–COOAg (3b) were pre-
pared according to the previously described literature pro-
cedure [11]. The two different silver salts (3a,b) were used to
replace one or both chloride ligands in the phosphine-con-
taining [RuCl2(@CH–o-O–iPr–C6H4)(PCy3)] (1) and the
phosphine-free [RuCl2(@CH–o-O–iPr–C6H4)(SIMes)] (2)
catalysts. The steric and electronic influences of a different
N-substituted amide-bond on the synthesis and the activity
of the resulting ruthenium complexes was also investigated.
As illustrated in Scheme 2, substitution of one of the chlo-
ride ligands by reacting 1 equiv of 3a with 1 equiv of 2 in
dichloromethane, at room temperature leads to the forma-
tion of the ruthenium complex 4 which contains mixed
anionic ligands. After removal of the AgCl by-product,
complex 4 was isolated in pure form, as an olive-green
powder, in 82% yield. Using 3b, compound 5 was prepared
as a green powder in 85% yield, but also 4% of the disub-
stituted catalyst 11 (see below) and 4% of catalyst 2 were
observed. Complex 5 displays two benzylidene proton sig-
Scheme 1.
NHC ligand (L) [5k,6] and the anionic ligand (X) [7–9],
avoid the problem of catalysts dissociating and bleeding
into the solution phase, because both ligands show little
tendency to dissociate from the metal center during
metathesis reaction. Buchowicz et al., Nieczpor et al. and
Buchmeiser et al. reported the synthesis of various homo-
geneous and heterogeneous ruthenium-based metathesis
catalysts prepared by replacement of one or both chloride
ligands by carboxylates resulting in stable systems [8–10].
When using fluorinated carboxylates a dramatic increase
in reactivity has been observed. Based on these results we
envisaged extending the concept by replacing the chloride
ligands in the Hoveyda-Grubbs first and second generation
catalysts by electron withdrawing ligands bearing a silyl-
oxygroup; a suitable handle allowing for immobilization
on silica gel. We chose trialkoxysilyl-functionalized sil-
ver(I) carboxylates as building blocks [11]. In the present
work, we achieved for the first time to synthesize and iso-
late the stable and highly active monosubstituted fluoro-
carboxylate ruthenium complexes [RuCl((RO)3Si–C3H6–
N(R0)CO–C3F6–COO)(@CH–o-O–iPr–C6H4)(SIMes)] (4:
R = Et, R0 = H; 5: R = R0 = Me). There are few examples
of ruthenium complexes with mixed anionic ligands known
[6g,8a,8d,9,12], but to the best of our knowledge we are
reporting for the first time upon stable and isolatable cata-
lysts based upon this structural motif of synthesizing both
mono- and disubstituted fluorocarboxylate ruthenium
complexes. We describe herein a direct comparison of sta-
bility and reactivity of the mono- and disubstituted cata-
lysts. Furthermore, these novel homogeneous complexes
give access to heterogeneous catalysts through the follow-
ing immobilization step. Silica gel was chosen as the solid
support due to the ease of functionalization whilst avoiding
the disadvantages of swelling and mechanical destruction
associated with other solid-supported systems on organic
polymers [13,14]. It should be mentioned that our synthetic
sequence provides convenient access to use either the
homogeneous or the heterogeneous catalyst, as the immo-
bilization step occurs last in the sequence. Moreover the
direct comparison between both homogeneous and hetero-
geneous species concerning their reactivity and stability has
been made possible. We hereby describe the synthesis of
mono- and disubstituted homogeneous catalysts by substi-
tution of one or both chlorides in the Hoveyda-Grubbs first
(1) and second generation (2) catalysts. Furthermore, the
heterogenization on silica gel is described. In addition the
influence of the substitution pattern on the reactivity and
stability is compared by RCM reaction of N,N-diallyl-p-
toluenesulfonamide.
1
nals in the H NMR spectrum (Table 1, entry 3). This is a
direct consequence of the Z/E-amide bonds from the
ligand. The Z/E ratio of the ruthenium complex is exactly
the same as observed in the NMR of silver salt 3b.
In contrast, attempts to synthesize the monosubstituted
complexes from 1 was achieved with limited success. Only
an inseparable 2:1:1 mixture of mono- and disubstituted
products as well as 1, could be isolated. We tentatively
attributed this to the increased steric bulk and more basic
character of the SIMes ligand in 2 compared to the rela-
tively small PCy3 ligand in 1 and the difference in donor
ability. The electron-withdrawing fluorocarboxylate
ligands decrease the electron density at the ruthenium cen-
ter and should lead to a stronger Ru–Cl bond. As a conse-
quence of this binding, substitution of the second chloride
is less favored [8d]. In order to investigate the influence of
the alkoxysilyl group on the observed monosubstitution we
reacted 1 equiv of 2 with 1 equiv of the alkoxysilyl-free
(iPr)2N–CO–C3F6–COOAg (6) [11] (Scheme 2). Using
THF instead of CH2Cl2 afforded the olive-green complex
7 in 92% yield, but 4% of the disubstituted catalyst 13
(see below) and 4% of 2 were also isolated. The silyl-free
monocarboxylate complex 7 was found to be unstable in
solution, especially in chlorinated solvents and dispropor-
tionated to 2 and 13. Indeed, after stirring in CDCl3 for
16 h at room temperature, a mixture of 7 (54%), 2 (21%)
and 13 (21%) was obtained. From these results we tenta-
tively attributed the higher stability of 4 and 5 to a stabiliz-
ing coordination of the alkoxysilyl-moiety to the
ruthenium center. This kind of interaction was also
observed for the trialkoxysilyl-functionalized silver(I) carb-
oxylates [11]. However, substitution of both chlorines by

K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
5269
SIMes
Cl
Ru
Cl
O
2
3a or 3b
6
O
O
O
O
SIMes
Ru
SIMes
Ru
O
O
(RO)3Si
3N
R'
N
3
F
3
F
F F
Cl
Cl
O
O
4: R = Et, R' = H
5: R = R' = Me
7
Scheme 2. Synthesis of the homogeneous, monocarboxylated ruthenium catalysts 4, 5 and 7.
Table 1
signals are even further downfield shifted compare to 1
and 2, respectively (1H: ca. 1 ppm; 13C: ca. 28 ppm). This
suggests a decrease in electron density at the ruthenium
center due to the additive effect of the first and second elec-
tron-withdrawing fluorocarboxylate ligand (Table 1).
1H and 13C NMR dataa
Entry
Complex
1H
13C
Phosphine-free ruthenium complexes
1
2
3
4
5
6
7
2
4
16.52
17.14
17.11, 17.09 (t)b
17.06c
17.56
17.51
17.54
295.8
307.4
306.9
305.1c
316.6
316.0
315.4
5
2.2. Synthesis of the heterogeneous Ru complexes
7
9
11
13
Immobilization of the homogeneous mono- (4, 5) and
bis-carboxylate (8–11) ruthenium catalysts on silica gel
was performed via pre-treatment of the silica support prior
to the actual immobilization step (Scheme 4). This involved
washing the silica successively with methanol, dichloro-
methane and hexane in order to remove any impurities,
and drying at 200 °C under high vacuum for 4 h to achieve
thermal desorption of physically adsorbed water molecules
from the silica gel surface.
The complexes were attached to the silica surface by
adding a solution of the homogeneous monosubstituted
Ru-catalysts 4 and 5 and disubstituted Ru-catalysts 8–11
in toluene to a silica/toluene suspension and stirring the
reaction mixture at room temperature. After heterogeniza-
tion of the catalysts, the free SiOH-groups were subse-
quently capped with dimethoxydimethylsilane. The
supported catalysts 4a and 5a containing mixed anionic
ligands were isolated as olive-green solids, and the disubsti-
tuted catalysts 8a–11a as light brown solids by filtration
and thorough washing with CH2Cl2 and hexane. The cata-
lyst loadings were determined by quantitative measurement
of the remaining ruthenium in the combined filtrates by
GF-AAS. Loadings between 31 and 65 lmol gꢀ1 were
achieved. The heterogeneous catalysts showed good stabil-
ity when stored at +4 °C under argon for 4 weeks without
any sign of decomposition.
Phosphine-containing ruthenium complexes
8
9
1
8
17.39 (d)
18.55 (d)
18.52 (d)
18.51 (d)
280.6d
308.4
307.9
308.2
10
11
a
10
12
Chemical shifts are given in ppm and measured in CD2Cl2.
Consists of Z/E amide-products in the ratio of 1/0.6.
Measured in THF-d8.
b
c
d
Value taken from Ref. [15].
adding 2 equiv of silver carboxylates 3a, b or 6 to 1 equiv of
1 or 2 gave the disubstituted phosphine-containing com-
plexes 8, 10 and 12 as well as the phosphine-free complexes
9, 11 and 13, which were isolated in pure form and in good
yields (77–93%) (Scheme 3). Complexes 8, 10 and 12 repre-
sent halide-free Hoveyda-Grubbs first generation com-
plexes. Only a handful of such complexes are known [9].
Formation of the mono- and bis-carboxylate ruthenium
complexes was corroborated by a significant low-field shift
of the benzylidene H NMR and 13C NMR resonances
compared to the respective signals for 1 and 2 (Table 1).
1
1
While monosubstitution shifts the H signal of the benzyl-
idene group ca. 0.5 ppm and the 13C signal ca. 10 ppm
downfield, in the doubly substituted complexes these

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K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
O
O
O
O
L
L
O
N
O
O
3
F
(RO)3Si
(RO)3Si
3N
R'
3
F
F
F
Ru
Ru
O
O
O
O
O
O
3N
R'
3
F
O
N
3
F
F
F
8: L = PCy3, R = Et, R' = H
9: L = SIMes, R = Et, R' = H
12: L = PCy3
13: L = SIMes
10: L = PCy3, R = R' = Me
11: L = SIMes, R = R' = Me
Scheme 3. Homogeneous, chlorine-free, disubstituted ruthenium catalysts 8–13.
O
O
F F
F F
OR
Si
L
O
Si
O
O
O
N
O
Ru
F
F
R'
Cl
OH
Si
Si
Si
4,5
O
O
O
O
CH3
CH3
O
O
Si
O
O
Si
4a: L = SIMes, R = Et, R' = H
5a: L = SIMes, R = R' = Me
OH
OH
O
OH
OH
O
O
O
O
Si
Si
Si
1) 4,5,8-11, toluene, 4h, rt
OH
OH
2) (CH3)2Si(OCH3)2, 20h, rt
OH
OH
OH
O
O
F F
OR
O
Si
O
O
O
L
N
O
Si
F
F F F
R'
Ru
CH3
CH3
O
Si
Si
Si
Si
O
O
F F
O
O
8-11
O
O
O
N
R'
O
Si
OR
O
O
F
F F F
O
Si CH3
CH3
O
O
8a: L = PCy3, R = Et, R' = H
9a: L = SIMes, R = Et, R' = H
10a: L = PCy3, R = R' = Me
11a: L = SIMes, R = R' = Me
Scheme 4. Immobilization of the complexes 4, 5 and 8–11 onto silica gel.
2.3. Reactivity of homogeneous catalysts in RCM
measuring catalyst activity representing the maximum reac-
tivity of a particular system in the chosen solvent [16]. It
must be pointed out that only TONs at the same catalyst
loading can reasonably be compared. To limit reaction rate
to a level useful for comparison, relatively small catalyst
loadings were employed. The TONs and conversions that
were obtained during the RCM of 14 are shown in Table 2.
When comparing the conversions obtained from the dif-
ferent phospine-free catalysts utilizing identical loadings it
is clear that the monosubstituted catalyst 4 displays compa-
rable activity to the Hoveyda-Grubbs second generation
catalyst (2) (Fig. 1). The monosubstituted catalyst 5 also
shows high activity, but when compared to 4 and 2 the
observed TONs are slightly lower (Fig. 1). TONs of 4860
for 2, 5050 for 4 and 4490 for 5 were calculated (Table 2,
In order to assess the activities of the complexes 4, 5 and
8–11, a standard RCM reaction with N,N-diallyl-p-tolu-
enesulfonamide (14) was used (Scheme 5).
Turn-over numbers (TONs) rather than yields have
emerged as an important method to measure the activity
of a catalyst, and have become the preferred indicator for
Ts
Ts
N
[Ru], 0.05M, CH2Cl2, Δ
N
14
15
Scheme 5.

K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
5271
Table 2
RCM of 14 with the homogeneous Ru-catalystsa
Entry
Cat.
Loading 0.01 mol%
Conv.b (%)
Loading 0.02 mol%
Conv.b (%)
TON
TON
Phosphine-free ruthenium complexes
1
2
3
4
5
Hoveyda-Grubbs second
Monocarboxylate complexes
2
4
49
51
45
27
19
4860
5050
4490
2690
1870
66
66
57
39
27
3300
3290
3850
1970
1360
5
Bis-carboxylate complexes
9
11
Phosphine-containing ruthenium complexes
6
7
8
Hoveyda-Grubbs first
Bis-carboxylate complexes
1
8
76
6
50
7600
580
5000
92
41
88
4600
2060
4410
10
a
Conditions: 0.05 M solution of 14, solvent CH2Cl2, T = 45 °C, t = 14 h.
Conversions determined by HPLC.
b
100
90
80
70
60
50
40
30
20
10
0
2
4
5
9
11
0
0.01
0.02
0.03
0.04
0.05
catalyst [mol%]
0.06
0.07
0.08
0.09
0.1
Fig. 1. RCM of 14: comparison of the conversion as a function of catalyst loading of the homogeneous, phosphine-free, mono- (4, 5) and bis-carboxylate
(9, 11) catalysts with 2.
entries 1–3). However, when both chloride ligands are
exchanged the resultant catalysts 9 and 11 clearly show a
decreased activity (Fig. 1). Thus, TONs of 2690 for 9 and
1870 for 11 were observed (Table 2, entries 4 and 5). As
before catalyst 11 with the disubstituted amide group dis-
played a slightly decreased activity compared to 9.
Hoveyda-Grubbs first generation catalyst (1), the activity is
significantly lower (Table 2, entries 6–8). Interestingly,
complex 10 with the disubstituted amide group shows
higher activity compared to complex 8 with the monosub-
stituted amide group.
The phosphine-containing disubstituted catalysts 8 and
10 also displayed high activity. Their observed TONs
(2060 for 8 and 4410 for 10) were higher compared to the
phosphine-free, disubstituted catalysts 9 and 11 (Table 2,
entries 7, 8 and 4, 5). However, compared with the parent
2.4. Reactivity of the supported catalysts
The trend observed for the homogeneous catalyst could
also be observed for the supported catalysts. As can be
deduced from Table 3, the silica gel bound catalysts contain-

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K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
Table 3
gel. They are catalytically active and displayed an increased
activity to similar polymer-bound systems. However, only
when compared to their homogeneous counterparts their
activity is reduced. Further investigations of activity as well
as immobilization strategies in order to reduce ruthenium
leaching is in progress.
RCM of 14 with the supported Ru-catalystsa
Entry
Cat.
Loading 0.02 mol%
Loading 0.1 mol%
Conv.b (%)
TON
Conv.b (%)
TON
1
2
3
4
5
6
a
4a
5a
13
13
10
24
28
19
670
670
520
1170
1380
960
90
87
75
64
85
88
900
870
750
640
850
880
9a
11a
8a
4. Experimental
10a
4.1. General information
Conditions: 0.05 M solution of 14, solvent CH2Cl2, T = 45 °C,
t = 14 h.
b
NMR data were recorded using a Bruker DPX 250
Advance, Bruker AMX 300 or Bruker DRX 500 Advance.
The spectra are referenced using the signals of the residual
solvent as internal standards. Fourier transform IR spec-
troscopy on KBr pellets were performed with a Bruker Equi-
nox 55 FT–IR instrument. ATR spectra were recorded using
Perkin–Elmer Spectrometer 881. Elemental analyses were
measured by a Vario EL. Ruthenium-content was measured
by GF-AAS (k = 240.272 nm) by a SpectrAA 880Z with
Zeeman background correction. Synthesis of the catalysts
was performed under an argon atmosphere by standard
Schlenk techniques or in an Argon-mediated dry-box (Lab-
master 130, Mbraun, Germany) unless stated otherwise.
Solvents were dried before use, employing standard drying
agents [17]. [RuCl2(@CH–o-O–iPr–C6H4)(PCy3)] (1) was
purchase from Aldrich, silica gel 60 was purchased from
Merck. [RuCl2(@CH–o-O–iPr–C6H4)(SIMes)] (2) [18],
(EtO)3Si–C3H6–NH–CO–C3F6–COOAg (3a) [11] and
(MeO)3Si–C3H6–N(Me)–CO–C3F6–COOAg (3b) [11] were
prepared according to the literature. All other commercially
available chemicals were used as received without further
purification.
Conversions determined by HPLC.
ing mixed anionic ligands 4a and 5a were more active then
their disubstituted counterparts 9a and 11a (entries 1–4).
However, there was not such a marked difference. All sup-
ported catalysts displayed considerably lower TONs than
their homogeneous counterparts. But compared to similar
polymer-bound systems reported by Buchmeiser et al. the
silica bound catalysts (1a, 5a and 8a–11a) clearly rival their
activity [9]. TONs of between 640 and 900 were achieved.
In order to determine the ruthenium content of the final
RCM products due to possible catalyst leaching, GF-AAS
measurements were carried out. When the reactions were
run using 5 mol% of the complex, ruthenium contamina-
tion in the products of 10–186 ppm was observed. This
ruthenium residues are in a range detected for other silica
supported ruthenium catalysts [5f]. The observed leaching
for the both phosphine-containing disubstituted catalysts
8a and 10a was the lowest (10 ppm for 8a and 21 ppm
for 10a). The phosphine-free systems gave ruthenium con-
tamination of 97, 186, 42 and 31 ppm, respectively, for cat-
alysts 4a, 5a, 9a and 11a. Two observations stand out: first,
the leaching from the chloride-free, disubstituted com-
plexes was generally lower and may be due to the double
attachment to the solid support and second, the catalysts
5a and 11a, containing disubstituted amide groups, dis-
played higher leaching then 4a and 9a with monosubsti-
tuted amide bonds.
4.2. Synthesis
4.2.1. [RuCl((EtO)3Si–C3H6–NH–CO–C3F6–
COO)(@CH–o-O–iPr–C6H4)(SIMes)] (4)
A solution of 3a (100.4 mg, 159.6 lmol, 1 equiv) in dry
CH2Cl2 (40 ml) was slowly added to a stirred solution of
2 (100.0 mg, 159.6 lmol, 1 equiv) in dry CH2Cl2 (10 ml).
While stirring was continued for 60 min, the color of the
reaction mixture changed from green to olive green and a
white, disperse precipitate formed. The precipitate was fil-
tered off and the filtrate was evaporated to dryness. The
residue was dissolved in CH2Cl2 (2 ml) and n-hexane
(6 ml) added. A white precipitation formed that was filtered
off. Removal of the solvent and drying under high vacuum
afforded 135.3 mg (130.9 lmol, 82.0%) of a olive green
powder. 1H NMR (250 MHz, CD2Cl2): d 17.14 (s, 1H,
CH@Ar), 7.48 (dt, J = 7.8 Hz, 1.8 Hz, 1H, aromat. CH),
7.17, 7.07 (s, 4H, mes.-CH), 7.02 (dd, J = 7.5 Hz, 1.8 Hz,
1H, aromat. CH), 6.94 (t, J = 7.1 Hz, 1H, aromat. CH),
6.76 (br s, 1H, NH), 6.76 (d, J = 8.3 Hz, 1H, aromat.
CH), 4.69 (septet, J = 6.1 Hz, 1H, iPr–CH), 4.14 (s, 4H,
imidazol-CH2), 3.80 (q, J = 7.0 Hz, 6H, Si–OCH2), 3.20
(q, J = 6.7 Hz, 2H, CH2NH), 2.46 (s, 6H, mes.-o-CH3),
3. Conclusion
In summary, we have developed a new strategy for syn-
thesizing ruthenium catalysts which can be used both
homogeneously or supported on silica. The advantage of
performing the chloride exchange before the immobiliza-
tion step avoids the problem of separation the insoluble sil-
ver chloride from the insoluble silica-bound catalysts. The
synthesis of the homogeneous complexes take place by
selective exchange of one or both chloride ligands with par-
tially fluorinated trialkoxysilyl-containing silver(I) carb-
oxylates. The homogenous monoexchanged complexes
rivaled the reactivity of the parent Hoveyda-Grubbs cata-
lyst, whereas a loss of reactivity was observed for the chlo-
ride-free disubstituted complexes. The silica-supported
derivatives were obtained by facile reaction with silica

K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
5273
2.43 (s, 6H, mes.-p-CH3), 2.25 (s, 6H, mes.-o-CH3), 1.57
(m, 2H, Si—CH2–CH2), 1.21 (t, J = 7.0 Hz, 9H, Si–
OCH2–CH3), 1.02 (d, J = 6.1 Hz, 3H, iPr–CH3), 0.98 (m,
3H, iPr–CH3), 0.57 (t, J = 8.0 Hz, 2H, SiCH2). 19F NMR
(235 MHz, CD2Cl2): d ꢀ124.5, ꢀ124.3 (2s, 2F, CF2),
ꢀ119.7, ꢀ119.4 (2t, 2F, CF2CONH), ꢀ115.1, ꢀ114.8 (dt,
t, 2F, CF2COORu). 13C NMR (75.5 MHz, CD2Cl2): d
307.4 (CH@Ar), 210.7 (imidazol-CN), 161.3 (COO),
158.7 (CONH), 153.4 (aromat. C), 144.6 (aromat. C),
139.6 (mes.-p-C), 139.5, 139.1 (mes.-o-C), 135.7 (mes.-C–
N), 130.3 (aromat. C), 129.9 (mes.-CH), 123.0 (aromat.
C), 122.7 (aromat. C), 112.7 (aromat. C), 111.3
(CF2CONH), 109.7 (CF2COORu), 108.1 (CF2), 75.6
(iPr–CH), 58.9 (SiOCH2), 51.9 (imidazol-CH2), 42.5
(CH2NH), 22.7 (Si–CH2–CH2), 21.3 (mes.-p-CH3), 20.5
(iPr–CH3), 19.2 (br s, mes.-o-CH3), 18.7 (mes.-o-CH3),
18.5 (Si–OCH2–CH3), 8.0 (Si–CH2). IR (KBr): m 3072
(w), 2976 (m), 2925 (m), 2895 (w), 1772 (w), 1717 (vs),
1700 (vs), 1592 (w), 1577 (w), 1540 (m), 1482 (m), 1455
(m), 1399 (w), 1387 (m), 1377 (w), 1355 (w), 1297 (w),
1266 (s), 1215 (w), 1157 (vs), 1113 (s), 1100 (s), 1078 (s),
1038 (w), 940 (m), 851 (w), 841 (m), 798 (m), 749 (m). Anal.
Calc. for C45H60ClF6N3O7RuSi2: C, 52.29; H, 5.85; N,
4.07. Found: C, 52.2; H, 5.9; N, 4.0%.
o-CH3), 6.6, 6.4 (2s, Si–CH2). IR (ATR): m 2964 (m),
2942 (m), 2923 (m), 2842 (w), 1781 (w), 1694 (vs), 1680
(vs), 1607 (w), 1592 (w), 1577 (w), 1482 (m), 1454 (m),
1399 (w), 1386 (w), 1377 (w), 1353 (w), 1293 (w), 1263
(vs), 1214 (w), 1157 (vs), 1113 (s), 1090 (vs), 1035 (m),
939 (m), 878 (w), 853 (w), 841 (w), 817 (m), 798 (m), 750
(m).
4.2.3. [RuCl(iPr)2N–CO–C3F6–COO)(@CH–o-O–iPr–
C6H4)(SIMes)] (7)
A solution of 6 (17.2 mg, 39.9 lmol, 1 equiv) in dry THF
(5 ml) was slowly added to a stirred solution of 2 (25.0 mg,
39.9 mmol, 1 equiv) in THF (5 ml). While stirring was con-
tinued for 60 min, in dark, the color of the reaction mixture
changed from green to olive-green and a white precipitate
formed. The precipitate was filtered off and the filtrate
was filtered through Celite. Drying in vacuo provided a
olive-green powder. Yield: 33.5 mg (36.7 lmol, 91.9%)
olive-green powder (purity: 92% 7, 4% 13, 4% 2). 1H
NMR (250 MHz, THF-d8): d 17.06 (s, 1H, CH@Ar), 7.37
(dt, J = 7.8 Hz, 1.3 Hz, 1H, aromat. CH), 7.13, 7.03 (2 s,
4H, mes.-CH), 6.91 (dd, J = 7.7 Hz, 1.3 Hz, 1H, aromat.
CH), 6.83 (d, 1H, aromat. CH), 6.82 (m, 1H, aromat.
CH), 4.74 (septet, J = 6.6 Hz, 1H, iPr–CH(@CH–o-O–
iPr–C6H4)), 4.15 (m, 2H, imidazol-CH2), 4.08 (septet,
J = 6.6 Hz, 1H, iPr–CH), 3.49 (septet, J = 6.7 Hz, 1H,
iPr–CH), 2.49 (s, 6H, mes.-o-CH3), 2.40 (s, 6H, mes.-p-
CH3), 2.26 (s, 6H, mes.-o-CH3), 1.32 (m, 6H, iPr–CH3),
1.23 (d, J = 5.9 Hz, 3H, iPr–CH3(@CH–o-O–iPr–C6H4)),
1.06 (d, J = 6.6 Hz, 6H, iPr–CH3), 1.04 (d, J = 5.9 Hz,
3H, iPr–CH3(@CH–o-iPr–C6H4)). 19F NMR (235 MHz,
THF-d8): d ꢀ123.6 (2s, 2F, CF2), ꢀ116.3 (t, J = 10.7 Hz,
1F, CF2COORu), ꢀ116.1 (t, J = 10.0 Hz, 1F, CF2COORu),
ꢀ113.4(t), ꢀ112.8(t) (td, J(F,F) = 278.5, 10.0 Hz, 1F,
CF2CON), ꢀ111.9(t), ꢀ111.3(t) (td, J(F,F) = 278.7, 10.6
Hz, 1F, CF2CON). 13C NMR (75.5 MHz, THF-d8): d
305.1 (CH@Ar), 212.5 (imidazol-CN), 161.1 (COORu),
157.5 (CONH), 154.3 (aromat. C), 145.4 (aromat. C),
140.5, 140.3 (mes.-o-C), 139.6 (mes.-p-C), 130.7 (aromat.
C), 130.6, 130.4 (mes.-CH), 130.3 (aromat. CH), 123.6
(aromat. C), 122.8 (aromat. C), 113.3 (aromat. C), 75.9
(iPr–CH(@CH–o-O–iPr–C6H4)), 51.9 (imidazol-CH2),
49.5 (iPr–CH), 48.3 (iPr–CH), 21.5 (iPr–CH3), 21.5 (iPr–
CH(@CH–o-O–iPr–C6H4)), 21.1 (mes.-p-CH3), 20.8
(mes.o-CH3), 20.3 (iPr–CH3), 19.3 (mes.-o-CH3). IR
(ATR): m 2969 (m), 2924 (s), 2854 (m), 2735 (w), 1695
(vs), 1677 (vs), 1607 (w), 1592 (w), 1577 (w), 1478 (m),
1454 (m), 1398 (w), 1377 (m), 1339 (w), 1263 (s), 1214 (w),
1156 (vs), 1114 (m), 1099 (w), 1049 (w), 1025 (m), 940
(m), 893 (w), 876 (w), 852 (w), 842 (w), 798 (m), 748 (m).
4.2.2. [RuCl((MeO)3Si–C3H6–N(Me)–CO– C3F6–
COO)(@CH–o-O–iPr–C6H4)(SIMes)] (5)
Compound 5 was prepared in analogous manner to the
synthesis of 4 from 2 (101.7 mg, 162.3 lmol, 1 equiv) and
3b (84.8 mg, 162.3 lmol, 1 equiv). Yield: 135.5 mg
(134.8 lmol, 83.0%) olive green powder (purity: 92% 5,
1
4% 11, 4% 2). H NMR (250 MHz, CD2Cl2): d 17.11 (s,
1H, E-CH@Ar), 17.09 (t, J(F,H) = 2.1 Hz, 1H, Z-
CH@Ar), 7.46 (dt, J = 7.7 Hz, 1H, aromat. CH), 7.16,
7.07 (2s, 4H, mes.-CH), 7.02 (dd, J = 7.6 Hz, 1.8 Hz, 1H,
aromat. CH), 6.93 (t, J = 7.3 Hz, 1H, aromat. CH), 6.75
(d, J = 8.4 Hz, 1H, aromat. CH), 4.68 (septet, J = 6.1 Hz,
1H, Z-iPr–CH), 4.68 (septet, J = 5.9 Hz, 1H, E-iPr–CH),
4.14 (s, 4H, imidazol-CH2), 3.54, 3.42 (2 s, 9H, Si–
OCH3), 3.28 (m, 2H, CH2N(CH3)), 2.91 (s, 3H, E-
N(CH3)), 2.89 (t, J(F,H) = 2.2 Hz, 3H, Z-N(CH3)), 2.43
(s, 6H, mes.-p-CH3), 2.45, 2.27 (2 s, 12H, mes.-o-CH3),
1.63 (m, 2H, Si–CH2–CH2), 1.02 (d, J = 6.1 Hz, 6H, Z-
iPr–CH3), 0.99 (d, J = 5.9 Hz, 6H, E-iPr–CH3), 0.55 (2t,
J = 8.3 Hz, 2H, SiCH2). 19F NMR (235 MHz, CD2Cl2): d
ꢀ122.1, ꢀ122.0, ꢀ122.0, ꢀ121.9 (4s, 2F, CF2), ꢀ115.3,
ꢀ115.0, ꢀ114.9, ꢀ114.6 (4t, 2F, CF2CONH), ꢀ112.0,
ꢀ111.7, ꢀ111.4, ꢀ111.3 (4t, 2F, CF2COORu). 13C NMR
(75.5 MHz, CD2Cl2): d 306.9 (CH@Ar), 210.9 (imidazol-
CN), 161.1 (COORu), 158.5 (CON(Me)), 153.4 (aromat.
C), 144.6 (aromat. C), 139.6 (mes.-o-C), 139.4 (mes.-p-C),
135.9 (mes.-C–N), 130.0 (aromat. C), 129.9 (2s, mes.-
CH), 123.9 (aromat. C), 122.7 (aromat. C), 112.6 (aromat.
C), 111.6 (CF2CON(Me)), 111.6 (CF2COORu), 108.3
(CF2), 75.6 (iPr–CH), 52.4 (CH2N(Me)), 51.9 (imidazol-
CH2), 50.8 (OCH3), 35.5 (NCH3), 21.1 (mes.-p-CH3),
20.6 (iPr–CH3), 20.1 (Si–CH2–CH2), 19.2, 18.7 (2s, mes.-
4.2.4. [Ru((EtO)3Si–C3H6–NH–CO–C3F6–
COO)2(@CH–o-O–iPr–C6H4)(PCy3)] (8)
A solution of 3a (214.7 mg, 341.3 lmol, 2.05 equiv) in
dry CH2Cl2 (40 ml) was slowly added to a stirred solution
of 1 (100.0 mg, 166.5 lmol, 1 equiv) in CH2Cl2 (10 ml).
While stirring was continued for 60 min, the color of the

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K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
reaction mixture changed from brown to violet and a
white, disperse precipitate formed. The precipitate was fil-
tered off and the filtrate was evaporated to dryness. The
residue was dissolved in CH2Cl2 (2 ml) and n-hexane
(6 ml) added. A white precipitation formed that was filtered
off. Removal of the solvent and drying under high vacuum
afforded 181.8 mg (128.5 lmol, 77.2%) of a ruby colored
powder. 1H NMR (250 MHz, CD2Cl2): d 18.55 (d,
J(P,H) = 5.9 Hz, 1H, CH@Ar), 7.85 (dd, J = 7.5 Hz,
1.4 Hz, 1H, aromat. CH), 7.68 (dt, J = 7.2 Hz, 1.4 Hz,
1H, aromat. CH), 7.25 (t, J = 7.4 Hz, 1H, aromat. CH),
7.06 (d, J = 8.4 Hz, 1H, aromat. CH), 6.81 (t,
J(F,H) = 4.9 Hz, 2H, NH), 4.96 (septet, J = 6.2 Hz, 1H,
iPr–CH), 3.80 (q, J = 7.0 Hz, 12H, Si–OCH2), 3.26 (q,
J = 6.6 Hz, 4H, CH2NH), 2.10–1.26 (33H, PCy3), 1.63
(m, 4H, SiCH2–CH2), 1.46 (d, J = 6.2 Hz, 6H, iPr–CH3),
1.20 (t, J = 7.0 Hz, 18H, Si–OCH2–CH3), 0.59 (t,
J = 8.2 Hz, 4H, SiCH2). 31P NMR (250 MHz, CD2Cl2): d
57.6. 19F NMR (235 MHz, CD2Cl2): ꢀ123.8 (s, 4F, CF2),
ꢀ120.0 (m, 4F, CF2CON), ꢀ115.4 (m, 4F, CF2CORu).
13C NMR (75.5 MHz, CD2Cl2): d 308.4 (CH@Ar), 163.9
(t, J(C,F) = 26.6 Hz, COO), 158.6 (t, J(C,F) = 25.7 Hz,
CONH), 155.2 (aromat. C), 144.6 (aromat. C), 131.5 (aro-
mat. C), 124.3 (aromat. C), 123.5 (aromat. C), 113.5 (aro-
mat. C), 111.3 (CF2CONH), 109.8 (CF2COORu), 108.0
(CF2), 77.0 (iPr–CH), 58.9 (Si–OCH2), 42.5 (CH2NH),
34.7 (d, PCy3CH), 29.6 (PCy3CH2), 28.0 (d, PCy3CH2),
26.7 (PCy3CH2), 22.7 (Si–CH2–CH2), 21.3 (iPr–CH3),
18.5 (Si–OCH2–CH3), 8.0 (Si–CH2). IR (KBr): m 3077
(w), 2976 (m), 2934 (m), 2856 (w), 1777 (w), 1707 (vs),
1634 (m), 1592 (w), 1579 (s), 1546 (m), 1478 (m), 1454
(m), 1392 (m), 1378 (m), 1302 (m), 1270 (s), 1249 (m),
1163 (vs), 1115 (s), 1100 (s), 1079 (s), 942 (m), 929 (w),
890 (w), 844 (w), 801 (m), 748 (m). Anal. Calc. for
C56H89F12N2O13PRuSi2: C, 47.55; H, 6.34; N, 1.98. Found:
C, 47.4; H, 6.3; N, 2.1%.
316.6 (CH@Ar), 209.8 (imidazol-CN), 161.2 (COORu),
158.6 (CONH), 154.0 (aromat. C), 143.8 (aromat. C),
139.9 (mes.-o-C), 139.5 (mes.-p-C), 135.5 (mes.-C–N),
130.4 (aromat. C), 130.0 (mes.-CH), 123.8 (aromat. C),
122.7 (aromat. C), 111.7 (aromat. C), 111.1 (CF2CONH),
109.7 (CF2COORu), 108.1 (CF2), 75.3 (iPr–CH), 58.8
(Si–OCH2), 51.9 (imidazol-CH2), 42.5 (CH2NH), 22.6
(Si–CH2–CH2), 21.3 (mes.-p-CH3), 20.4 (iPr–CH3), 18.5
(Si–OCH2–CH3), 18.1 (mes.-o-CH3), 7.9 (Si–CH2). IR
(KBr): m 3083 (w), 2977 (m), 2927 (m), 2896 (w), 1705
(vs), 1595 (w), 1580 (w), 1545 (m), 1485 (m), 1456 (m),
1390 (m), 1378 (m), 1355 (w), 1269 (s), 1163 (vs), 1114
(s), 1100 (s), 1077 (s), 941 (m), 915 (w), 842 (w), 797 (m),
750 (m). Anal. Calc. for C59H82F12N4O13RuSi2: C, 49.19;
H, 5.74; N, 3.89. Found: C, 49.1; H, 5.8; N, 3.8%.
4.2.6. [Ru((MeO)3Si–C3H6–N(Me)–CO–C3F6–
COO)2(@CH–o-O–iPr–C6 H4)(PCy3)] (10)
Compound 10 was prepared analogously to 8 using 1
(100.8 mg, 167.8 lmol, 1 equiv) and 3b (184.0 mg, 352.4
lmol, 2.1 equiv) as starting materials. Yield: 153.5 mg
(112.9 lmol, 67.2%) ruby colored powder. 1H NMR
(250 MHz, CD2Cl2): d 18.52 (d, J(P,H) = 5.9 Hz, 1H,
CH@Ar), 7.84 (dd, J = 7.5 Hz, 1.5 Hz, 1H, aromat. CH),
7.67 (dt, J = 7.9 Hz, 1.4 Hz, 1H, aromat. CH), 7.24 (t,
J = 7.4 Hz, 1H, aromat. CH), 7.07 (d, J = 8.5 Hz, 1H, aro-
mat. CH), 4.96 (septet, J = 6.1 Hz, 1H, iPr–CH), 3.53 (s,
18H, Si–OCH3), 3.34 (t, J = 7.6 Hz, 4H, CH2N(Me)),
3.03 (t, 6H, J(F,H) = 2.0 Hz, Z-NCH3), 2.93 (s, 6H, E-
NCH3), 2.11–1.28 (33H, PCy3), 1.65 (m, 4H, SiCH2–
CH2), 1.46 (d, J = 6.2 Hz, 6H, iPr–CH3), 0.56 (t, J =
8.4 Hz, 4H, SiCH2). 31P NMR (250 MHz, CD2Cl2): d
56.9. 19F NMR (235 MHz, CD2Cl2): d ꢀ121.5 (s, 4F, E-
CF2), ꢀ121.4 (s, 4F, Z-CF2), ꢀ115.1 (t, J(F,F) = 11.5 Hz,
4F, Z-CF2CON(Me)), ꢀ114.9 (t, J(F,F) = 12.4 Hz, 4F,
E-CF2CON(Me)), ꢀ111.7 (t, J(F,F) = 12.0 Hz, 4F, Z-
CF2COORu), ꢀ111.2 (t, J(F,F) = 12.3 Hz, 4F, E-
CF2COORu). 13C NMR (75.5 MHz, CD2Cl2): d 307.9
(CH@Ar), 164.1 (COORu), 158.4 (CON(Me)), 155.2 (aro-
mat. C), 144.6 (aromat. C), 131.4 (aromat. C), 124.3 (aro-
mat. C), 123.5 (aromat. C), 113.6 (aromat. C), 111.6
(CF2CON(Me)), 111.6 (CF2COORu), 108.3 (CF2), 77.2
(iPr–CH), 53.1 (CH2N(Me)), 50.7 (OCH3), 35.5 (NCH3),
34.7 (d, PCy3CH), 29.6 (PCy3CH2), 28.0 (d, PCy3CH2),
26.7 (PCy3CH2), 22.3 (Si–CH2–CH2), 21.3 (iPr–CH3), 6.5
(Si–CH2). IR (KBr): m 3074 (w), 2928 (s), 2854 (m), 1786
(w), 1704 (s), 1681 (vs), 1632 (m), 1591 (m), 1579 (w),
1479 (m), 1454 (m), 1414 (m), 1393 (w), 1380 (w), 1354
(m), 1316 (w), 1296 (w), 1262 (s), 1164 (s), 1093 (vs),
1042 (s), 929 (m), 889 (w), 819 (m), 803 (m), 749 (m). Anal.
Calc. for C52H81F12N2O13PRuSi2: C, 45.98; H, 6.01; N,
2.06. Found: C, 46.1; H, 6.1; N, 2.0%.
4.2.5. [Ru((EtO)3Si–C3H6–NH–CO–C3F6–
COO)2(@CH–o-O–iPr–C6H4)(SIMes)] (9)
Compound 9 was prepared analogously to 8 using 2
(100.0 mg, 159.6 lmol, 1 equiv) and 3a (210.8 mg, 335.2
lmol, 2.1 equiv) as starting materials. Yield: 174.2 mg
1
(120.9 lmol, 75.8%) violet powder. H NMR (250 MHz,
CD2Cl2): d 17.56 (s, 1H, CH@Ar), 7.40 (dt, J = 7.8,
1.7 Hz, 1H, aromat. CH), 7.17 (s, 4H, mes.-CH), 7.09
(dd, J = 7.5 Hz, 1.7 Hz, 1H, aromat. CH), 6.98 (t,
J = 7.3 Hz, 1H, aromat. CH), 6.75 (t, J(F,H) = 5.1 Hz,
1H, NH), 6.67 (d, J = 8.4 Hz, 1H, aromat. CH), 4.56 (sep-
tet, J = 6.1 Hz, 1H, iPr–CH), 4.12 (s, 4H, imidazol-CH2),
3.80 (q, J = 7.0 Hz, 12H, Si–OCH2), 3.22 (q, J = 6.6 Hz,
4H, CH2NH), 2.46 (s, 6H, mes.-p-CH3), 2.26 (s, 12H,
mes.-o-CH3), 1.58 (m, 4H, Si–CH2–CH2), 1.21 (t,
J = 7.0 Hz, 18H, Si–OCH2–CH3), 0.96 (d, J = 6.1 Hz,
6H, iPr–CH3), 0.57 (t, J = 8.0 Hz, 4H, SiCH2). 19F NMR
(235 MHz, CD2Cl2): d ꢀ126.0, ꢀ126.1 (2s, 4F, CF2),
ꢀ121.5, ꢀ121.4 (2t, 4F, CF2CONH), ꢀ116.7, ꢀ116.7 (2t,
4F, CF2COORu). 13C NMR (75.5 MHz, CD2Cl2): d
4.2.7. [Ru((MeO)3Si–C3H6–N(Me)–CO–C3F6–
COO)2(@CH–o-O–iPr–C6H4)(SIMes)] (11)
Compound 11 was prepared analogously to 8 using 2
(100.2 mg, 159.9 lmol, 1 equiv) and 3b (185.8 mg, 355.8

K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
5275
lmol, 2.1 equiv) as starting materials. Yield: 205.4 mg
(157.7 lmol, 92.8%) violet powder. H NMR (250 MHz,
C), 122.4 (aromat. C), 113.8 (aromat. C), 111.9
(CF2COORu), 111.5 (CF2), 108.2 (CF2CON), 77.2 (iPr–
CH(@CH–o-O–iPr–C6H4)), 49.1 (iPr–CH), 48.1 (iPr–
CH), 34.6 (d, J(P,C) = 24.2 Hz, PCy3CH), 29.6 (PCy3
CH2), 28.0 (d, J(P,C) = 10.5 Hz, PCy3CH2), 26.7
(PCy3CH2), 21.3 (iPr–CH(@CH–o-O–iPr–C6H4)), 20.7
(iPr–CH3), 19.9 (iPr–CH). IR (KBr): m 2971 (w), 2933 (s),
2856 (m), 1705 (s), 1679 (vs), 1633 (m), 1591 (w), 1579
(w), 1477 (m), 1448 (m), 1391 (w), 1380 (m), 1339 (m),
1302 (w), 1262 (m), 1246 (w), 1209 (m), 1159 (vs), 1115
(s), 1099 (w), 1051 (m), 1026 (m), 929 (m), 893 (w), 873
(w), 850 (w), 827 (w), 801 (m), 749 (m). Anal. Calc. for
C50H73F12N2O7PRu: C, 51.14; H, 6.27; N, 2.39. Found:
C, 51.0; H, 6.3; N, 2.3%.
1
CD2Cl2): d 17.51 (s, 1H, CH@Ar), 7.38 (dt, J = 7.8, 1.6
Hz, 1H, aromat. CH), 7.17 (s, 4H, aromat. mes.-CH), 7.08
(dd, J = 7.5, 1.5 Hz, 1H, aromat. CH), 6.96 (t, J = 7.4 Hz,
1H, aromat. CH), 6.66 (d, J = 8.3 Hz, 1H, aromat. CH),
4.55 (septet, J = 6.0 Hz, 1H, iPr–CH), 4.12 (s, 4H, imi-
dazol-CH2), 3.54 (18H, Si–OCH2), 3.28 (m, 4H,
CH2N(CH3)), 2.91 (br s, 6H, N(CH3)), 2.45 (s, 6H, mes.-p-
CH3), 2.27 (s, 12H, mes.-o-CH3), 1.63 (m, 4H, Si–CH2–
CH2), 0.97 (d, J = 6.1 Hz, 6H, iPr–CH3), 0.55 (t,
J = 8.4 Hz, 4H, SiCH2). 19F NMR (235 MHz, CD2Cl2): d
ꢀ122.0 (m, 4F, CF2), ꢀ115.2 (t, J(F,F) = 11.2 Hz, 2F, Z-
CF2COORu), ꢀ115.0 (m, 1F, Z-CF2COORu), ꢀ114.9 (t,
J(F,F) = 11.6 Hz, 4F, E-CF2COORu), ꢀ114.5 (q, J(F,F) =
11.3 Hz, 1F, Z-CF2COORu), ꢀ111.9 (t, J(F,F) = 11.2 Hz,
2F, Z-CF2CON(Me)), ꢀ111.7 (t, J(F,F) = 10.7 Hz, 2F,
Z-CF2CON(Me)), ꢀ111.4 (t, J(F,F) = 11.9 Hz, 2F, E-
CF2CON(Me)), ꢀ111.3 (t, J(F,F) = 11.8 Hz, 2F, E-
CF2CON(Me)). 13C NMR (75.5 MHz, CD2Cl2): d 316.0
(CH@Ar), 210.3 (imidazol-CN), 161.1 (COORu), 158.5
(CON(Me)), 154.0 (aromat. C), 143.9 (aromat. C), 139.9
(mes.-o-C), 139.5 (mes.-p-C), 135.2 (mes.-C–N), 130.3
(aromat. C), 130.0 (mes.-CH), 123.9 (aromat. C), 122.7 (aro-
mat. C), 111.7 (aromat. C), 112.1 (CF2CON(Me)), 111.0
(CF2COORu), 108.4 (CF2), 75.3 (iPr–CH), 53.1 (CH2N-
(Me)) 52.4 (imidazol-CH2), 50.8 (OCH3), 35.5 (NCH3),
22.3 (Si–CH2–CH2), 21.3 (mes.-p-CH3), 20.5 (iPr–CH3),
18.2 (mes.-o-CH3), 6.6 (Si–CH2). IR (KBr): m 3075 (w),
2945 (m), 2922 (m), 2845 (w), 1705 (m), 1678 (m), 1610 (w),
1595 (w), 1580 (w), 1548 (m), 1485 (m), 1455 (m), 1378 (m),
1352 (w), 1266 (s), 1162 (s), 1073 (vs), 942 (m), 879 (w), 842
(w), 823 (m), 796 (m), 748 (m). Anal. Calc. for
C55H74F12N4O13RuSi2: C, 47.70; H, 5.39; N, 4.04. Found:
C, 47.8; H, 5.5; N, 3.9%.
4.2.9. [Ru((iPr)2)2N–CO–C3F6–COO)2(@CH–o-O–iPr–
C6H4)(SIMes)] (13)
Compound 13 was prepared analogously to 7 using 2
(34.2 mg, 54.6 lmol, 1 equiv) and 6 (51.6 mg, 120.0 lmol,
2.2 equiv) as starting materials. While stirring was contin-
ued for 60 min, the color of the reaction mixture changed
from green to pink and a white, disperse precipitate
formed. The precipitate was filtered off and the filtrated
was concentrated in vacuo. The solid was redissolved in
CH2Cl2 and passed over a short pad of silica. Elution with
CH2Cl2 removed 2 and 11 as a green band from the col-
umn. The following addition of ethyl acetate/n-hexane (1/
2) supply a violet band. The solvent was evaporated and
the resulting solid was dried under vacuum to give
31.8 mg violet powder (26.5 lmol, 48.6%). 1H NMR
(250 MHz, THF-d8): d 17.54 (s, 1H, CH@Ar), 7.28 (dt,
J = 7.0 Hz, 1.7 Hz, 1H, aromat. CH), 7.14 (s, 4H, mes.-
CH), 6.97 (dd, J = 7.5, 1.6 Hz, 1H, aromat. CH), 6.83 (t,
J = 7.0 Hz, 1H, aromat. CH), 6.72 (d, J = 8.3 Hz, 1H,
aromat. CH), 4.63 (septet, J = 6.1 Hz, 1H, iPr–
CH(@CH–o-O–iPr–C6H4)), 4.14 (s, 4H, imidazol-CH2),
4.08 (septet, J = 6.7 Hz, 2H, iPr–CH), 3.49 (septet,
J = 6.7 Hz, 2H, iPr–CH), 2.43 (s, 6H, mes.-p-CH3), 2.30
(s, 12H, mes.-o-CH3), 1.33 (d, J = 6.7 Hz, 12H, iPr–CH3),
1.07 (t, J = 5.5 Hz, 12H, iPr–CH3), 1.00 (d, J = 6.1 Hz,
6H, iPr–CH3(@CH–o-O–iPr–C6H4)). 19F NMR (235
MHz, THF-d8): d ꢀ120.3, ꢀ120.2 (2s, 4F, CF2), ꢀ112.9
(m, 4F, CF2COORu), ꢀ109.3 (t, J(F,F) = 11.1 Hz, 2F,
CF2CON), ꢀ108.7 (t, J(F,F) = 10.7 Hz, 2F, CF2CON).
13C NMR (75.5 MHz, THF-d8): d 315.4 (CH@Ar), 211.2
(imidazol-CN), 161.0 (COORu), 157.4 (CONH), 154.5
(aromat. C), 144.1 (aromat. C), 140.0 (mes.-o-C), 139.9
(mes.-p-C), 136.9 (mes.-C–N), 130.5 (aromat. C), 130.1
(mes.-CH), 124.1 (aromat. C), 122.3 (aromat. C), 112.1
(CF2COORu), 111.9 (aromat. C), 111.1 (CF2), 108.7
(CF2CON), 75.3 (iPr–CH(@CH–o-O–iPr–C6H4)), 51.9
(imidazol-CH2), 48.9, 47.8 (iPr–CH), 21.0 (mes.-p-CH3),
20.5 (iPr–CH3), 20.3 (iPr–CH(@CH–o-O–iPr–C6H4)),
19.8 (iPr–CH), 18.3 (mes.-o-CH3). IR (KBr): m 2966 (m),
2924 (m), 2854 (w), 1705 (s), 1679 (vs), 1595 (w), 1580
(w), 1484 (m), 1456 (m), 1446 (m), 1400 (m), 1379 (m),
1338 (m), 1263 (vs), 1211 (m), 1157 (vs), 1114 (s), 1099
4.2.8. [Ru((iPr)2)2N–CO–C3F6–COO)2(@CH–o-O–iPr–
C6H4)(PCy3)] (12)
Compound 12 was prepared analogously to 8 using 1
(10.5 mg, 17.5 lmol, 1 equiv) and 6 (16.5 mg, 38.4 lmol,
2.1 equiv) as starting materials. Yield: 18.1 mg (15.4 lmol,
1
87.9%) crimson powder. H NMR (250 MHz, CD2Cl2): d
18.51 (d, J(P,H) = 5.9 Hz, 1H, CH@Ar), 7.84 (dd,
J = 7.5, 1.6 Hz, 1H, aromat. CH), 7.67 (dt, J = 7.9 Hz,
1.5 Hz, 1H, aromat. CH), 7.24 (t, J = 7.4 Hz, 1H, aromat.
CH), 7.07 (d, J = 8.4 Hz, 1H, aromat. CH), 4.96 (dseptet,
J = 6.3, 1.2 Hz, 1H, iPr–CH(@CH–o-O–iPr–C6H4)), 4.22
(septet, J = 6.5 Hz, 2H, iPr–CH), 3.51 (septet, J = 6.8 Hz,
2H, iPr–CH), 2.11–1.21 (33H, PCy3), 1.46 (d, J = 6.3 Hz,
6H, iPr–CH3(@CH–o-O–iPr–C6H4)), 1.37 (d, J = 6.8 Hz,
12H, iPr–CH), 1.16 (d, J = 6.5 Hz, 12H, iPr–CH). 31P
NMR (250 MHz, CD2Cl2): d 57.9. 19F NMR (235 MHz,
CD2Cl2): d ꢀ122.0 (s, 4F, CF2), ꢀ115.8 (t, J(F,F) =
11.2 Hz, 4F, CF2COORu), ꢀ111.6 (t, J(F,F) = 11.8 Hz,
4F, CF2CON). 13C NMR (75.5 MHz, CD2Cl2): d 308.2
(CH@Ar), 164.4 (COORu), 157.2 (CON), 155.4 (aromat.
C), 144.8 (aromat. C), 131.3 (aromat. C), 124.3 (aromat.

5276
K. Vehlow et al. / Journal of Organometallic Chemistry 691 (2006) 5267–5277
(m), 1049 (m), 1022 (s), 941 (m), 894 (w), 877 (w), 852 (w),
843 (w), 797 (s), 748 (m). Anal. Calc. for
C53H66F12N4O7Ru: C, 53.04; H, 5.54; N, 4.67. Found: C,
53.1; H, 5.5; N, 4.7%.
4.3.6. [Ru([SG]–C3H6–N(Me)–CO–C3F6–COO)2(@CH–
o-O–iPr–C6H4)(SIMes)] (11a)
Starting with 11 (52.9 mg, 38.2 lmol) in 6 ml toluene,
SG-60 (382.6 mg) in 6 ml toluene and dimethoxydimethyl
silane (124.7 ll, 894.5 lmol), 11a was obtained as light
brown solid. Ru content 58.9 lmol gꢀ1, corresponding to
4.3. General procedure for heterogenization on silica gel 60
81.6 mg catalysts gꢀ1
.
The silica gel (SG-60) was washed successively with
MeOH, CH2Cl2 and n-hexane. After dehydration for 4 h
at 200 °C in vacuo, SG-60 (200–400 mg) was suspended
in dry toluene and a solution of homogeneous catalysts
in toluene was added. The resulting suspension was stirred
at room temperature for 4 h. Dimethoxydimethylsilane was
added dropwise and stirring was continued for additional
20 h. The product was isolated by filtration and washed
with CH2Cl2 and n-hexane. Drying in vacuo over night
afforded the product.
4.3.7. Leaching tests
For the determination of the arisen Leachings, the
metathesis samples with 5 mol% catalyst were used. The
suspensions were filtered and the filtrate were evaporated
to dryness. The investigation of the ruthenium quantities
took place by GF-AAS.
Acknowledgements
We are grateful to the analytical department of Merck
KGaA for NMR, IR and GF-AAS spectroscopic measure-
ments and C, H, N analyses and the Graduiertenkolleg
‘‘Synthetische, mechanistische und reaktionstechnische As-
pekte von Metallkatalysatoren’’ for financial support.
4.3.1. [RuCl([SG]–C3H6–NH–CO–C3F6–COO)(@CH–o-
O–iPr–C6H4)(SIMes)] (4a)
Starting with 4 (44.8 mg, 30.9 lmol) in 6 ml toluene, SG-
60 (433.5 mg) in 6 ml toluene and dimethoxydimethyl
silane (139.0 ll, 996.9 lmol), 4a was obtained as olive green
solid. Ru content 31.5 lmol gꢀ1, corresponding to 32.6 mg
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