Preparation of hydrido(vinylidene)ruthenium(II) complexes and a one-pot synthesis of Grubbs-type ruthenium carbenes

Article abstract of DOI:10.1039/b502440d

Treatment of the hydrido(dihydrogen) compound [RuHCl(H₂) (PCy₃)₂] 1 with alkynes RC≡CH (R = H, Ph) afforded the hydrido(vinylidene) complexes [RuHCl(=C=CHR)(PCy₃)₂] 2, 3 which react with HCl or [HPCy₃]Cl to give the corresponding Grubbs-type ruthenium carbenes [RuCl₂(=CHCH₂R)(PCy ₃)₂] 4, 5. The reaction of 2 (R = H) with DCl, or D ₂O in the presence of chloride sources, led to the formation of [RuCl₂(=CHCH₂D)(PCy₃)₂] 4-d ₁. Based on these observations, a one-pot synthesis of compounds 4 and 5 was developed using RuCl₃·3H₂O as the starting material. The hydrido(vinylidene) derivative 2 reacted with CF ₃CO₂H and HCN at low temperatures to yield the carbene complexes [RuCl(X)(=CHCH₃)(PCy₃)₂] 6,7, of which 7 (X = CN) was characterized crystallographically. Salt metathesis of 2 with CF₃CO₂K and KI led to the formation of [RuH(X)(=C=CH₂)(PCy₃)₂] 8, 9. The bis(trifluoracetato) and the diiodo compounds [RuX₂(=CHCH ₃)(PCy₃)₂] 10,11 as well as the new phosphine P(thp)₃ 12 (thp = 4-tetrahydropyranyl) and the corresponding complex [RuCl₂(=CHCH₃){P(thp)₃}₂] 14 were also prepared. The catalytic activity of the ruthenium carbenes 4-7, 10, 11 and 14 in the olefin cross-metathesis of cyclopentene and allyl alcohol was investigated. The Royal Society of Chemistry 2005.

Full text of DOI:10.1039/b502440d

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F U L L P A P E R
Preparation of hydrido(vinylidene)ruthenium(II) complexes and a
one-pot synthesis of Grubbs-type ruthenium carbenes†
Wolfram Stu¨er, Birgit Weberndo¨rfer, Justin Wolf and Helmut Werner*
Institut fur Anorganische Chemie der Universita¨t Wu¨rzburg, Am Hubland, D-97074, Wu¨rzburg,
Germany. E-mail: helmut.werner@mail.uni-wuerzburg.de
Received 17th February 2005, Accepted 24th March 2005
First published as an Advance Article on the web 13th April 2005
Treatment of the hydrido(dihydrogen) compound [RuHCl(H2)(PCy3)2] 1 with alkynes RC≡CH (R = H, Ph) afforded
= =
the hydrido(vinylidene) complexes [RuHCl( C CHR)(PCy3)2] 2, 3 which react with HCl or [HPCy3]Cl to give the
=
corresponding Grubbs-type ruthenium carbenes [RuCl2( CHCH2R)(PCy3)2] 4, 5. The reaction of 2 (R = H) with
=
DCl, or D2O in the presence of chloride sources, led to the formation of [RuCl2( CHCH2D)(PCy3)2] 4-d1. Based on
these observations, a one-pot synthesis of compounds 4 and 5 was developed using RuCl3·3H2O as the starting
material. The hydrido(vinylidene) derivative 2 reacted with CF3CO2H and HCN at low temperatures to yield the
=
carbene complexes [RuCl(X)( CHCH3)(PCy3)2] 6, 7, of which 7 (X = CN) was characterized crystallographically.
= =
Salt metathesis of 2 with CF3CO2K and KI led to the formation of [RuH(X)( C CH2)(PCy3)2] 8, 9. The
=
bis(trifluoracetato) and the diiodo compounds [RuX2( CHCH3)(PCy3)2] 10, 11 as well as the new phosphine P(thp)3
=
12 (thp = 4-tetrahydropyranyl) and the corresponding complex [RuCl2( CHCH3){P(thp)3}2] 14 were also prepared.
The catalytic activity of the ruthenium carbenes 4–7, 10, 11 and 14 in the olefin cross-metathesis of cyclopentene and
allyl alcohol was investigated.
Introduction
Results and discussion
In the context of our investigations on the chemistry of
ruthenium complexes containing Ru(PiPr3)2 as the building
block, we recently reported the preparation and molecu-
lar structure of the six-coordinate ruthenium(IV) compound
[RuH2Cl2(PiPr3)2] which was formed from [RuCl2(C8H12)]n
and PiPr3 in 2-butanol under a hydrogen atmosphere via
the hydrido(dihydrogen) complex [RuHCl(H2)(PiPr3)2] as an
intermediate.1,2 The reaction of [RuH2Cl2(PiPr3)2] with a two-
fold excess of phenylacetylene gave the expected vinylidene
Preparation and reactivity of five-coordinate hydrido(vinylidene)
ruthenium complexes
By attempting to develope a synthetic route to ruthenium
=
carbenes [RuCl2( CHR)(PCy3)2] without using [RuCl2(PPh3)3]
as the precursor, both we and the Grubbs group found that the
probably polymeric cyclooctadiene derivative [RuCl2(C8H12)]n
reacts in a suspension of 2-butanol with PCy3 under a
hydrogen atmosphere to give nearly quantitatively the hy-
drido(dihydrogen) complex [RuHCl(H2)(PCy3)2] 1.2,6 Treatment
of this compound, which was first prepared by Chaudret and
= =
compound [RuCl2( C CHPh)(PiPr3)2] but, quite surprisingly,
under the chosen conditions small amounts of the ruthenium
4
6
co-workers from [Ru(g -C8H12)(g -C8H10)],7 with acetylene in
CH2Cl2 at low temperatures affords the hydrido(vinylidene)
complex 2 in 94% yield (Scheme 1). The reaction has to be
stopped after ca. 10 seconds, since compound 2 reacts quickly
with an excess of C2H2 to form some oily ill-defined by-products.
Phenylacetylene behaves similarly as C2H2 and with 1 gives the
phenylvinylidene complex 3.
=
carbene [RuCl2( CHCH2Ph)(PiPr3)2] were equally obtained.
Since this complex can be considered as a near relative of
3,4
=
the Grubbs-type catalyst [RuCl2( CHPh)(PCy3)2], we were
prompted to find out whether ruthenium carbenes of the general
=
composition [RuCl2( CHR)(PCy3)2] would be accessible from
[RuCl2(C8H12)]n or, even more simply, from RuCl3·3H2O as the
starting material.
The present paper reports two versions of a one-pot syn-
=
thesis of the carbene complexes [RuCl2( CHR)(PCy3)2] (R =
CH3, CH2Ph) from RuCl3·3H2O as the precursor, the prepa-
ration of the hydrido(vinylidene) ruthenium(II) compounds
ꢀ
ꢀ
= =
[RuHCl( C CHR )(PCy3)2] (R = H, Ph) which are intermedi-
ates in the generation of the respective carbenes, and the conver-
=
sion of both the carbenes [RuCl2( CHR)(PCy3)2] and the vinyli-
= =
dene [RuHCl( C CH2)(PCy3)2] into derivatives having iodide
or trifluoroacetate instead of chloride as ligands. The prepara-
tion of the new phosphine P(thp)3 (thp = 4-tetrahydropyranyl)
=
and its ruthenium complex [RuCl2( CHCH3){P(thp)3}2] as well
as the catalytic activity of various ruthenium carbenes in the
olefin cross-metathesis of cyclopentene and allyl alcohol is also
described. Some preliminary results of this work have already
been communicated.5
Scheme 1 (L = PCy3).
† Dedicated to Professor Henri Brunner on the occasion of his 70th
birthday, in honour of his pioneering work in metal-chirality and
catalysis.
The hydrido(vinylidene) compounds 2 and 3 are air-sensitive
solids, which are quite labile and, even if they are stored at
1 7 9 6
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3
T h i s j o u r n a l i s
T h e R o y a l S o c i e t y o f C h e m i s t r y 2 0 0 5
©

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at d 316.5, both appearing as triplets. The 31P NMR spectrum of
5 displays a single resonance at d 34.6, thus indicating that the
phosphine ligands are trans disposed.
To explain the mechanism of the reaction of 2 or 3 with
=
HCl, we assume that in the initial step HCl attacks the C C
double bond of the vinylidene ligand to generate intermediate
A (see Scheme 2, route a) which is converted to the 14-electron
species B by insertion of the carbene ligand into the Ru–H bond.
From B the target complex 4 or 5 could be generated by an
a-Cl shift from carbon to the metal. Although the formation
of a-chloroalkyl ruthenium(II) compounds (corresponding to
B) as short-lived intermediates has also been proposed by
Grubbs and co-workers in the preparation of the carbene
=
complexes [RuCl2( CHCH2R)(PCy3)2] (R = H, Me) from 1
6
=
and vinyl chlorides RCH CHCl, an alternative mechanism
for the conversion of 2, 3 to 4, 5 should not be excluded.
By taking some recent observations from our laboratory into
account,9 it is also conceivable that HCl reacts initially with the
hydrido(vinylidene) compounds to give the cationic ruthenium
carbyne [RuHCl(≡CCH2R)(PCy3)2]Cl C (seeScheme 2, route b).
After addition of the chloride ion to the metal centre of C, the
hexa-coordinate intermediate D would be formed which in the
final step could generate the five-coordinate ruthenium carbene
via an a-H shift. The result that the monodeuterated derivative
[RuCl2( CHCH2D)(PCy3)2] 4-d1 (characterized by H and D
NMR spectroscopy) is obtained exclusively from 2 and DCl in
benzene/D2O seems to be in agreement with either mechanistic
scheme.
1
2
Scheme 2 (L = PCy3; R = H, Ph).
=
−20 ◦C under argon, decompose in 4–6 days. Thus, they are
significantly less stable than the triisopropylphosphine counter-
2
parts [RuHCl( C CHR)(PiPr3)2]. The 13C NMR spectra of
= =
2 and 3 display in the low-field region the typical signals for
the a- and b-carbon atoms of the vinylidene ligand at d 326.2
and 86.6 (for 2) and d 329.1 and 109.1 (for 3), which are all
split into triplets due to P–C coupling. In the 1H NMR spectra
the hydride resonance also appears as a triplet at d −16.17 (for
2) and d −12.88 (for 3). The chemical shifts are rather similar
One-pot synthesis of the Grubbs-type ruthenium carbenes
After we found that the relatively weak acid [HPCy3]Cl is
sufficient as a source of HCl for the conversion of 2 and 3 to
the carbene complexes 4 and 5, we also attempted to find out
whether the first stepofthe reaction is a nucleophilic attack ofthe
chloride at the a-C atom of the vinylidene ligand or at the metal
centre. We therefore investigated the reactions of compound 2
with [Ph3PNPPh3]Cl ([PNP]Cl) and MgCl2 in THF. Whereas in
the first case no reaction occurred, with MgCl2 small amounts
of 4 were formed. The assumption, that the residual content
of water in the MgCl2 or in the solvent is responsible for this
process, was confirmed by addition of extra water to the reaction
mixture of 2 and MgCl2, which led to complete conversion of
2 to the carbene complex 4 within seconds. In contrast, the
reaction of 2 with [PNP]Cl and H2O is significantly slower and
only completed after about 5 h. The active role of MgCl2 in the
formation of 4 is also supported by the fact that in the presence
of MgCl2, but not of [PNP]Cl, acetylene can serve as a proton
source instead of water.
= =
to those of the related complexes [RuHCl( C CHR)(PiPr3)2]
= =
(R = H, Ph) and [RuHCl( C CHR)(PtBu2Me)2] (R = SiMe3,
Ph), the latter of which were recently prepared by Caulton and
co-workers and, according to ab initio DFT calculations, should
possess a distorted trigonal-bipyramidal coordination sphere
with the phosphine ligands in the apical positions.8
If the hydrido(vinylidene) compounds 2 and 3 are dissolved
in acetone or CH2Cl2 and then treated with an aqueous solution
of HCl, a quick change of colour from brown or green to
violet occurs and the Grubbs-type carbene complexes 4 and
5 are formed in virtually quantitative yield. Instead of HCl the
phosphonium salt [HPCy3]Cl, in dichloromethane as solvent,
can also be used. Moreover, 4 and 5 can be directly obtained by
treatment of 1 with acetylene or phenylacetylene in the presence
of one equivalent of [HPCy3]Cl (see Scheme 1). While compound
By taking these results into consideration, we concluded that
1, acetylene, MgCl2 and H2O should give the carbene complex
4 via the intermediate formation of 2. This conclusion led us to
develop the first one-pot synthesis of 4 (method (a), Scheme 3).5
Commercially available RuCl3·3H2O in THF was reduced in
the presence of PCy3 with Mg/1,2-C2H4Cl2 under a hydrogen
4 was known, being first prepared by Grubbs and co-workers
3
=
from [RuCl2( CHPh)(PCy3)2] and propene, the benzylcarbene
complex 5 has not been described as yet. Typical spectroscopic
1
=
features of 5 are the H NMR resonance for the Ru CH proton
at d 19.40 and the 13C NMR signal for the carbene carbon atom
Scheme 3 (L = PCy3; R = H, Ph).
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3
1 7 9 7

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atmosphere at 60–85 ◦C to compound 1. The activation of
magnesium with 1,2-dichloroethane serves not only to accelerate
the reduction, but also to increase the concentration of MgCl2.
After the reaction mixture was cooled to −40 ◦C, acetylene
(about two equivalents) was introduced along with a small excess
of water. While warming the solution to room temperature, the
carbene complex 4 is formed and, after removal of the solvent
in vacuo and extraction of the residue with pentane, isolated in
about 75% yield. In a similar manner, by using phenylacetylene
as the source for the carbene ligand, compound 5 was obtained.
In this case we observed that under the reaction conditions the
intermediate 1 reacts with phenylacetylene by substitution of H2.
Therefore, in contrast to the formation of 4, only one equivalent
of the alkyne is needed for the preparation of 5. Both 4 and 5
show nearly the same activity as the standard Grubbs catalyst
pound 6 is partly converted to the dichloro carbene 4 without
observing the formation of the bis(trifluoracetato) complex 10.
Thus, for the catalytic studies discussed below, solutions with the
in-situ generated compound 6 have been used. The reaction of
2 with gaseous HCN in THF at −78 ◦C gave the chloro(cyano)
complex 7, which was isolated as an orange, moderately air-
1
sensitive solid in 86% yield. The H NMR spectra of 6 and 7
=
display for the Ru CH proton a low-field resonance at d 19.85
(for 6) and d 18.25 (for 7) being split into a quartet due to 3J(H,H)
coupling. We note that the only other ruthenium carbene of
=
the general composition [RuCl(X)( CHR)(PCy3)2] is the com-
=
=
pound [RuCl(O2CCF3)( CHCH CPh2)(PCy3)2], which was
mentioned in a patent without giving details about the stability,
spectroscopic data, etc.15 Attempts to obtain the chloro(fluoro)
=
complex [RuCl(F)( CHCH3)(PCy3)2] from 2 and hydrogen
=
[RuCl2( CHPh)(PCy3)2] in olefin metathesis (ROMP and RCM)
fluoride failed.
and in the meantime have been prepared in an industrial research
The result of the X-ray crystal structure analysis of 7 is
shown in Fig. 1. The molecular diagram illustrates that the
coordination geometry around the metal center corresponds to
that of a distorted square pyramid with the carbene ligand in
the apical position. The two phosphines and the cyano and
the chloro ligand are trans-disposed. The P(1)-Ru–P(2) axis
is significantly bent (161.0(1)◦) with the phosphorus atoms
pointing away from the carbene unit. The distance Ru–C(2) of
laboratory in 100 g quantities.10
More recently, the preparative route to give 4 and 5 was
even more simplified. Instead of using Mg/1,2-C2H4Cl2 and
THF as solvent, we used isoprene and 2-propanol as reagents
to convert RuCl3·3H2O into a more reactive intermediate. This
3
3
intermediate probably is the dinuclear compound [RuCl2(g :g -
C10H16)]2, which was first reported by Porri et al.11,12 and
was shown, in independent studies by us, that it reacts with
PCy3 in 2-propanol under a hydrogen atmosphere to give the
hydrido(dihydrogen) complex 1 in nearly quantitative yield.13
By taking into account that treatment of 1 with acetylene, a
proton and a chloride source furnishes the ruthenium carbene
4, we prepared this compound along method (b) in Scheme 3.
The main and important advantage is that instead of a ca. 4-
fold excess of PCy3 (as used for method a) only two equivalents
of the phosphine are needed to achieve an 80% yield of the
carbene complex 4. The 1H NMR spectrum of the crude reaction
˚
1.810(6) A (Table 1) is virtually identical to that in the complex
1
˚
=
[RuCl2( CHCH2Ph)(PiPr3)2] (1.813(5) A) but slightly shorter
=
than in the Grubbs compound [RuCl2( CH-p-C6H4Cl)(PCy3)2]
3
˚
(1.839(3) A). Although the cyano and the chloro ligand are
disordered, the Ru–Cl bond length in 7 is significantly longer (ca.
˚
=
0.1 A) than the bond lengths in [RuCl2( CHCH2Ph)(PiPr3)2]
=
and [RuCl2( CH-p-C6H4Cl)(PCy3)2], probably due to the trans
influence of the cyanide.
product indicated that besides 4 small amounts (ca. 3–5%) of
14
=
the vinyl ruthenium derivative [RuCl(CH CH2)(CO)(PCy3)2]
were also formed but could be separated by washing the product
several times with methanol.
Ligand displacement reactions of five-coordinate carbene and
vinylidene ruthenium(II) complexes
In order to possibly find an even better application profile
for the ruthenium(II) carbenes in olefin metathesis, we also
exchanged one or both of the chloride ligands in compound 4 for
other anions. Treatment of a solution of the hydrido(vinylidene)
complex 2 in dichloromethane with an equimolar amount of
CF3CO2H at −78 ◦C led to a quick change of colour from
brown to dark red and gave, owing to the NMR data, the mixed
chloro(trifluoracetato) derivative 6 as the sole reaction product
(Scheme 4). If the solution is warmed to room temperature, com-
Fig. 1 An ORTEP plot of compound 7.32
The hydrido(vinylidene) complexes 8 and 9 were prepared
in good yields by salt metathesis of 2 with CF3CO2K and KI,
respectively. The iodo derivative 9 is even more labile than the
◦
a
˚
Table 1 Selected bond lengths (A) and angles ( ) for compound 7
Ru–C(1)
Ru–P(1)
Ru–P(2)
1.810(6)
2.407(2)
2.420(2)
Ru–Cl
Ru–C(3)
2.471(3)
1.92(1)
Ru–C(1)–C(2)
P(1)–Ru–P(2)
C(1)–Ru–P(2)
C(1)–Ru–Cl
132.7(5)
161.0(1)
100.4(2)
92.9(2)
Ru–C(3)–N(3)
C(1)–Ru–P(1)
C(1)–Ru–C(3)
C(3)–Ru–Cl
175.9(9)
98.6(2)
92.6(4)
174.4(3)
a The chloro and the cyano ligands are disordered and lie in two domains
with an occupancy factor of 71 : 29. Distances and angles are given only
for the molecule in the higher occupied domain.
Scheme 4 (L = PCy3).
1 7 9 8
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3

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chloro analogue 2 and thus has been characterized by low-
temperature NMR spectroscopy. Diagnostic features for both
8 and 9 are the high-field resonance for the hydride ligand in the
1H NMR spectra at d −13.16 (for 8) and d −10.10 (for 9) and
the low-field signal for the carbene carbon atom in the 13C NMR
spectra at d 332.9 (for 8) and d 325.3 (for 9). The IR spectrum
of 8 shows two bands for the asymmetric and symmetric OCO
stretching modes at 1604 and 1447 cm−1, which in agreement
with reference data16 suggests a chelating coordination of the
trifluoracetate unit.
In analogy to the conversion of 2 to 6, compound 8 also
reacts with CF3CO2H to give the bis(trifluoracetato) complex 10
in 94% yield. Owing to the lability of hydrido(iodo) derivative
9, the diiodide 11 is preferentially prepared from 4 and NaI
in THF. Both 10 and 11 are lightly coloured, practically
air-stable solids which have been characterized by elemental
analysis and spectroscopic techniques. They can be stored
under argon at −20 ◦C for weeks without decomposition.
In solutions of benzene or dichloromethane, compound 11 is
more labile than the bis(trifluoroacetate) 10, thus reflecting
the same order of stability as observed for 8 and 9. The
CF3CO2 ligands in 10 are probably coordinated in a monoden-
tate fashion, as is indicated by the relatively large difference
(236 cm−1) in the wave numbers of the asymmetric and symmetric
OCO stretching modes.16 We note that a relative of 10 hav-
13, following the standard methodology.3 Compound 14 is a
purple, only slightly air-sensitive solid that dissolves readily in
dichloromethane but is nearly insoluble in benzene and other
hydrocarbons. The 31P NMR spectrum of 14 (in CD2Cl2) shows
a single resonance with a chemical shift (d 30.7), that is almost
3
=
identical to that of [RuCl2( CHPh)(PCy3)2] 15 (d 30.63). In
1
=
the H NMR spectrum of 14, the Ru CH proton resonates as
a singlet at d 20.02, whereas the signal for the carbene carbon
atom appears in the 13C NMR spectrum as a triplet at d 299.3.
VT NMR measurements in a mixture of C6D6 and CDCl3 as the
solvent indicate no dynamic behaviour of the P(thp)3 ligands in
14 on the NMR timescale, which supports the data obtained for
the free phosphine.
Ruthenium carbenes as catalysts for the cross-olefin metathesis
of cyclopentene with allyl alcohol
Recently we reported that treatment of the Grubbs compound
15 with an excess of allyl alcohol generates the expected (hy-
=
droxymethyl)carbene derivative [RuCl2( CHCH2OH)(PCy3)2]
which, however, is unstable in solution and decom-
poses to give the carbonyl complex [RuCl2(CO)(PCy3)2].22
This smooth decomposition probably explains why in
the catalytic cross-olefin metathesis of cyclopentene with
=
CH2 CHCH2OH, leading to a mixture of unsaturated alcohols
CH2(CHCH2CH2CH2CH)nCHCH2OH with n = 1, 2 and 3 in the
ratio of 8 : 4 : 1, a fairly rapid de-activation of catalyst 15 occurs.23
Taking into consideration that the before-mentioned alcohols,
particularly those with n = 2 (C13) and 3 (C18), are widely
used in the fine-chemical industry, we attempted to get some
=
=
ing the composition [Ru(CF3CO2)2( CHCH CPh2)(PPh3)2]
was reported by Grubbs and co-workers and prepared from
17
=
=
[RuCl2( CHCH CPh2)(PPh3)2] and CF3CO2Ag.
A new sterically demanding tertiary phosphine
more information how the catalytic activity of the ruthenium
ꢀ
=
carbenes [RuX2( CHR)(PR 3)2] in the cross-olefin metathesis
In the search for analogues of the standard Grubbs-type cat-
=
of cyclopentene with allyl alcohol depends on the anionic ligand
X, the substituent R and the type of the phosphine. For this
purpose a mixture of cyclopentene (10 cm3) and allyl alcohol
(2.5 cm3) was treated with a catalytic amount (0.02–0.05 mol%)
of the carbene complex and, after it was stirred for 3 h at room
temperature, the product mixture was studied by GC/MS (see
Table 2). In another experiment, the conversion of the starting
materials C5H8 and C3H5OH to the higher unsaturated alcohols
with compound 4 as the catalyst was followed at particular
time intervals (see Table 3). The results of these studies can
be summarized as follows:
alyst [RuCl2( CHPh)(PCy3)2] containing ligands comparable
in size with PCy3, the related phosphine P(thp)3 12 (thp = 4-
tetrahydropyranyl) has been prepared from PCl3 and (thp)MgCl
(Scheme 5). The synthesis of the Grignard reagent is a little tricky
and needs both diethyl ether and THF as solvents. The subse-
quent reaction of (thp)MgCl with PCl3 is performed in toluene
at −25 ◦C and, after separation of MgCl2 and recrystallization
of the crude product from acetone, the phosphine 12 is obtained
1
analytically pure as a white solid in 53% yield. The H NMR
spectrum of 12 displays, besides the resonance for the PCH
proton, four signals for the CH2 protons, two of which corre-
sponding to the methylene protons in the axial (Ha) and two to
the methylene protons in the equatorial positions (He). Since the
spectrum does not change upon increasing the temperature to
80 ◦C, we conclude that in the range between 20 ◦C and 80 ◦C no
inversion of the tetrahydropyranyl rings occurs. The phosphorus
atom of 12 probably occupies an equatorial position at the six-
(i) By comparing the carbene complexes 4 and 5 with the
standard catalyst 15, it is quite obvious that the substituent R of
the carbene ligand has nearly no influence on the course of the
reaction. This is consistent with the proposal,3 that the starting
ꢀ
=
material reacts in the initial step with an olefin CH2 CHR
18
19
Table 2 Ratio of unsaturated alcohols CH2(CHCH2CH2CH2CH)n-
CHCH2OH with n = 1 (C8), 2 (C13) and 3 (C18) formed in the cross-olefin
metathesis of cyclopentene with allyl alcohol and ruthenium carbenes
as catalystsa
membered rings, similarly as found for CyPH2 or CyPMe2
and postulated for PCy3.20 This proposed stereochemistry is
supported by the size of one of the 3J(H,H) coupling constants
for the signal of the PCH proton in the 31P-decoupled 1H NMR
spectrum of 12, which is 12 Hz and thus in agreement with an
axial-axial arrangement of the respective protons.21
Catalyst
Ratio C8 : C13 : C18
=
[RuCl2( CHPh)(PCy3)2] 15
1.5 : 1 : 0.6
1.4 : 1 : 0.7
1.5 : 1 : 0.7
Only traces of metathesis
products
Only traces of metathesis
products
No metathesis products
Only traces of metathesis
products
10 : 1 : 0.2
2 : 1 : 0.3
=
[RuCl2( CHCH3)(PCy3)2] 4
=
[RuCl2( CHCH2Ph)(PCy3)2] 5
=
[RuCl(O2CCF3)( CHCH3)(PCy3)2] 6
=
[RuCl(CN)( CHCH3)(PCy3)2] 7
=
[Ru(O2CCF3)2( CHCH3)(PCy3)2] 10
=
[RuI2( CHCH3)(PCy3)2] 11
=
[RuCl2( CHPh){P(thp)3}2] 14
=
[RuCl2( CHCH3){P(Coc)3}2] 16
a Conditions: Starting materials, cyclopentene (10 cm3) and allyl alcohol
(2.5 cm3); amount of catalyst, 0.02 mol% (for 4, 5, 7, 15), 0.03 mol%
(for 8, 11, 14, 16) and 0.05 mol% (for 10); time of reaction 4 h at room
temperature.
Scheme 5 (L = P(thp)3 12).
The ruthenium carbene 14 with two P(thp)3 ligands has been
prepared in excellent yield from the well-known starting material
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3
1 7 9 9

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Table 3 Ratio of unsaturated alcohols CH2(CHCH2CH2CH2CH)nCHCH2OH with n = 1 (C8), 2 (C13), 3 (C18) and 4 (C23) formed in the cross-olefin
metathesis of cyclopentene with allyl alcohol and 4 as catalyst, depending on the time of the reactiona
Time/min
Conversion of C5H8 (%)
Conversion of C3H5OH (%)
C8 (%)
C13 (%)
C18 (%)
C23 (%)
2.5
5.0
10.0
20.0
45
11.9
21.9
29.7
47.1
52.0
56.9
58.3
91.0
26.1
45.8
66.1
74.0
76.8
78.5
79.9
96.0
56.7
55.6
46.0
46.1
43.9
42.7
40.7
26.7
31.3
30.6
31.0
31.0
30.6
30.3
30.4
27.2
11.9
12.1
17.2
18.7
18.8
18.4
19.8
29.6
0
1.6
5.8
4.2
6.7
8.6
9.2
16.4
90
1080
90b
a Conditions: Starting materials, cyclopentene (15 cm3), allyl alcohol (4 cm3) and 4 (39.5 mg, 0.05 mmol); room temperature. b After 1080 min a second
portion of 4 (39.5 mg, 0.05 mmol) was added to the mixture and 90 min later the ratio of products was determined.
=
to generate the methylene compound [RuCl2( CH2)(PCy3)2],
which subsequently forms the catalytically active species via a
dissociative mechanism.24
as the starting material. The two versions of the one-pot
synthesis not only avoid rather expensive starting materials
such as [RuCl2(PPh3)3]3 or [RuH2(H2)2(PCy3)2]29 but also uses
1-alkynes instead of diazoalkanes, vinyl chlorides or propargylic
chlorides as carbene sources. A crucial intermediate in the
formation of the ruthenium carbenes 4 and 5 from RuCl3·3H2O
is the hydrido(dihydrogen) compound 1, which reacts with
alkynes RC≡CH to give the hydrido(vinylidene) complexes 2
and 3 by displacement of the dihydrogen ligand. The conversion
of 2 and 3 to the five-coordinate carbene ruthenium derivatives
4 and 5 by treatment with aqueous HCl proceeds under mild
conditions and affords the products in nearly quantitative yields.
While the carbene complexes 4 and 5 display high catalytic
activity in ROMP of cycloolefins, comparable to that of the
Grubbs compound 15, they are (also similarly to 15) relatively
poor catalysts in the olefin cross-metathesis of cyclopentene
and allyl alcohol to give higher unsaturated C8, C13 and C18
alcohols. Displacing one or two of the chloro ligands in 4
by cyanide, iodide or trifluoracetate decreases the catalytic
activity of the respective ruthenium carbenes as does the
substitution of the PCy3 units in 4 by the sterically related tris(4-
tetrahydropyranyl)phosphine 12, first prepared in this work.
Thus it remains a challenge to find a catalyst that not only
effectively catalyzes the conversion of cycloolefins and C3H5OH
to the required long-chain unsaturated alcohols but also being
stable under the reaction conditions.
(ii) Regarding the anionic ligands, two chlorides are the
best. Even compounds 6 and 7, in which only one chloro
ligand of 4 is displaced by trifluoracetate or cyanide, are much
less active than 4. There is a significant difference between 4
and 11, the latter containing two iodo instead of two chloro
ligands. This observation is in agreement with results from
the Grubbs group,24,25 who found that the catalytic activity
=
of both 15 and [RuCl2( CHPh)(NHC)(PCy3)] (NCH = N-
heterocyclic carbene) in olefin metathesis and ROMP of cy-
clooctadiene decreases if the chlorides are displaced for iodides.
The bis(trifluoracetate) 10 is completely inactive in the cross-
=
olefin metathesis of cyclopentene with CH2 CHCH2OH. This is
surprising insofar as it was recently reported that replacing chlo-
ride for trifluoracetate in a Grubbs–Hoveyda-type ruthenium
catalyst allows the living and stereoselective cyclopolymerization
of diethyldipropargyl malonate (DEDPM) being not possible
with the dichloro analogue.26
(iii) The type of the phosphine influences to some extend the
ratio of the unsaturated C8, C13 and C18 alcohols formed from
C5H8 and C3H5OH. While substitution of PCy3 for P(Coc)3
(Coc = cyclooctyl) only slightly increases the fraction of C8
at the expense of C18, the use of P(thp)3 instead of PCy3 leads
predominantly to the formation of the shorter C8 alcohol. It
is conceivable that electronic effects are responsible for the
difference in activity between compounds 4 and 14.27 However,
it is important to note that the overall activity of 14 and
Experimental
=
[RuCl2( CHMe){P(Coc)3}2] 16, for example in ROMP of cis-
All experiments were carried out under an atmosphere
of argon by Schlenk techniques. The starting materi-
cyclooctene and dicyclopentadiene, is significantly less than that
of the PCy3 counterpart 15.28
als [RuHCl(H2)(PCy3)2] 1,13 [RuCl2( CHPh)(PPh3)2] 13,3
=
3
=
=
(iv) The relative amount of the C8, C13, C18 and C23 alcohols,
formed from cyclopentene and allyl alcohol with compound 4
as the catalyst, depends on the time of the reaction. Whereas
after 2.5 min 56.7% of the mixture of products consists of C8
and only 11.9% of C18, after 90 min the mixture contains 42.7%
of C8 and 18.4% of C18 plus 8.6% of C23. The relative amount
of C13 remains nearly constant. After ca. 20 min, the rate of
the reaction decreases considerably, which is probably due to
the de-activation of the catalyst by allyl alcohol. At the same
time, a change of colour from violet to yellow can be observed.
Subsequent addition of 0.05 mol% of 4 re-activates the olefinic
substrates and finally leads to a nearly quantitative consumption
of cyclopentene and allyl alcohol. Since for the reaction a molar
ratio of C5H8 : C3H5OH = 2.9 : 1 was used and part of the allyl
alcohol reacted with the catalyst, it is understandable that with
increasing time the relative amount of the C18 and C23 alcohols
increases.
[RuCl2( CHPh)(PCy3)2] 15, and [RuCl2( CHMe){P(Coc)3}2]
16,27 were prepared as described in the literature. NMR spectra
were recorded, if not otherwise stated, at room temperature on
Bruker AC 200 and Bruker AMX 400 instruments, and IR
spectra on a Perkin-Elmer 1420 or an IFS 25 FT-IR infrared
spectrometer. Melting points were measured by DTA. Abbrevi-
ations used: s, singlet; d, doublet; t, triplet; q, quartet; vt, virtual
triplet; m, multiplet; br, broadened signal; coupling constants J
2
4
and N in Hz; N = J(PC) + J(PC).
Preparations
= =
[RuHCl( C CH2)(PCy3)2] 2. A stream of acetylene was
passed for ca. 10 s through a solution of 1 (102 mg, 0.15 mmol)
in CH2Cl2 (5 cm3) at −78 ◦C. A change of colour from orange-
yellow to brown occurred. The solvent was evaporated in vacuo,
the remaining brown solid was washed twice with 3 cm3 portions
of pentane (−20 ◦C), and dried in vacuo; yield 99 mg (94%);
mp 109 ◦C (decomp.) (Found: C, 62.76; H, 9.32. C38H69ClP2Ru
Conclusion
=
requires: C, 63.00; H, 9.60%). IR (KBr): m(C C) 2065, m(RuH)
The results presented in this paper have shown that Grubbs-type
ruthenium carbenes can be prepared directly from RuCl3·3H2O
1905 cm−1. NMR (C6D6): dH (400 MHz) 2.70 [2 H, t, J(P,H)
=
3.0, C CH2], 2.61, 2.13, 1.65, 1.20 (66 H, all m, C6H11), −16.17
1 8 0 0
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3

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[1 H, t, J(P,H) 18.0, RuH]; dC (100.6 MHz) 326.2 [t, J(P,C) 15.0,
(2 cm3, 14.35 mmol), stirred for 5 min, and then PCy3 (2.24 g,
8.0 mol) was added. The suspension was stirred for 10 min, the
argon atmosphere was replaced by hydr◦ogen, and the mixture
was vigorously stirred for 45 min at 70 C. An orange–yellow
suspension was formed, which was cooled to room temperature
under the H2 atmosphere. After MgCl2·6H2O (1.60g, 7.87 mmol)
was added, a steady stream of acetylene (220 cm3, ca. 4.6 mmol)
was passed through the suspension for 90 min. The suspension
was stirred for 10 min, the small excess of acetylene was
evaporated in vacuo, and the mixture was poured into water
(200 cm3). A slightly exothermic reaction was observed. The
light-violet precipitate was filtered, washed four times with
50 cm3 portions of methanol, and dried in vacuo; yield 2.4 g
(80%); mp 116 ◦C (decomp.) (Found: C, 59.77; H, 8.90; Ru,
13.63. C38H70Cl2P2Ru requires: C, 59.98; H, 9.27; Ru, 13.28%).
=
=
C
CH2], 86.6 [t, J(P,C) 4.0, C CH2], 34.4, 31.0, 30.7, 27.1 (all s,
C6H11), 28.2, 28.0 (both vt, N 10.0, C6H11); dP (162.0 MHz) 41.5
(s).
= =
[RuHCl( C CHPh)(PCy3)2] 3. A solution of 1 (96 mg,
0.14 mmol) in CH2Cl2 (10 cm3) was treated with phenylacetylene
(0.028 cm3, 0.27 mmol) at −78 ◦C. After the solution was
warmed to room temperature, it was concentrated to ca. 1 cm3
in vacuo. Addition of pentane (10 cm3) led to the precipitation
of a green solid, which was separated from the mother-liquor,
washed three times with 5 cm3 portions of pentane and dried;
yield 80 mg (73%); mp 46 ◦C (decomp.) (Found: C, 65.77; H,
8.70. C44H73ClP2Ru requires: C, 66.02; H, 9.19%). IR (KBr):
−1
=
m(C C) 2065, m(RuH) 1900 cm . NMR (C6D6): dH (200 MHz)
=
7.05 (5 H, br m, C6H5), 4.41 (1 H, br s, CHPh), 2.50–1.10 (66 H,
=
br m, C6H11), −12.88 [1 H, t, J(P,H) 17.4, RuH]; dC (100.6 MHz)
One-pot synthesis of [RuCl2( CHCH2Ph)(PCy3)2] 5. This
=
329.1 [t, J(P,C) 12.0, C CHPh], 133.9, 128.6, 123.7, 123.4 (all s,
compound was prepared as described for 4, using method a,
from RuCl3·3H2O (0.50 g, 1.91 mmol), Mg (0.50 g, 20.6 mmol),
1,2-C2H4Cl2 (0.5 cm3) and PCy3 (2.31 g, 8.20 mmol). After
the reaction mixture was cooled to −40 ◦C, phenylacetylene
(0.22 cm3, 1.91 mmol) was added dropwise, which led to a
vigorou◦s evolution of gas. The suspension was stirred for 20 min
=
C6H5), 109.1 [t, J(P,C) 4.0, C CHPh], 35.2 (vt, N 19.0, C1 of
C6H11), 31.0, 30.6 (both s, C6H11), 28.1, 27.9 (both vt, N 10.0,
C6H11), 26.9 (s, C6H11); dP (162.0 MHz) 41.3 (s).
=
[RuCl2( CHCH3)(PCy3)2] 4. A suspension of 2 (56 mg,
0.08 mmol) in acetone (2 cm3) was treated with a 2 M solution
of HCl in water (0.05 cm3, 0.10 mmol) at room temperature.
The mixture was stirred for ca. 1 min and then a light-violet
solid began to precipitate. After 10 min the precipitate was
filtered, washed twice with 5 cm3 portions of acetone, and
dried in vacuo; yield 52 mg (89%). Alternatively, compound
4 can also be prepared in virtually quantitative yield from 2
(30 mg, 0.04 mmol) and an excess of [HPCy3]Cl (ca. 50 mg)
in 1 cm3of dichloromethane. The product was characterized by
◦
at −40 C, and after it was warmed to 0 C, water (0.13 cm3,
7.20 mmol) was added. The suspension was warmed to room
temperature, stirred for 10 min, and then the solvent was
evaporated in vacuo. The residue was extracted with toluene
(60 cm3), and the extract was brought to dryness in vacuo.
The remaining purple solid was washed four times with 10 cm3
portions of pentane, twice with 40 cm3 portions of methanol and
dried; yield 1.24 g (78%); mp 136 ◦C (decomp.) (Found: C, 63.23;
H, 8.72. C44H74Cl2P2Ru requires: C, 63.14; H, 8.91%). NMR
1
comparison of the H and 13C NMR data with those reported
=
(CDCl3): dH (400 MHz) 19.40 [1 H, t, J(H,H) 5.1, CHCH2Ph],
in the literature.3
=
7.21 (5 H, m, C6H5), 3.98 [2 H, d, J(H,H) 5.1, CHCH2Ph],
=
[RuCl2( CHCH2D)(PCy3)2] 4-d1. A solution of 2 (50 mg,
2.45 (6 H, m, C6H11), 1.79–1.63, 1.47–1.39, 1.23–1.12 (60 H, all
0.07 mmol) in benzene (3 cm3) was treated with a 37% solution
of DCl in D2O (0.06 cm3, 0.07 mmol) and stirred for 5 min at
room temperature. A change of colour from brown to violet
occurred. The solvent was evaporated in vacuo, the residue was
washed twice with 3 cm3 portions of acetone, and dried in
vacuo; yield 50 mg (94%). NMR (C6H6): dD (61.4 MHz) 2.62
m, C6H11); dC (100.6 MHz) 316.5 [t, J(P,C) 7.4, Ru C], 138.9,
=
128.3, 128.2, 126.3 (all s, C6H5), 64.5 (s, CH2Ph), 32.0 (vt, N
18.4, C1 of C6H11), 27.6 (vt, N 10.1, C6H11), 29.4, 26.3 (both s,
C6H11); dP (162.0 MHz) 34.6 (s).
Generation of compound 5 from 3. A solution of 3 (30 mg,
0.04 mmol) in C6D6 (1 cm3) was treated in an NMR tube with a
0.27 M solution of HCl in C6D6 (0.22 cm3, 0.06 mmol). A change
of colour from green to violet occurred. The 1H and 31P spectra
revealed that a quantitative conversion of 3 to 5 took place. In
an analogous experiment, a solution of 3 (30 mg, 0.04 mmol)
in CD2Cl2 (1 cm3) was treated with an excess of [HPCy3]Cl (ca.
50 mg) and stirred for 15 min. Also under these conditions, a
quantitative formation of 5 was observed.
=
(br s, CHCH2D). NMR (C6D6): dH (200 MHz) 19.67 (1 H,
=
br s, Ru CH), 2.78 (6 H, m, C6H11), 2.63, 2.62 (2 H, both m,
=
CHCH2D), 2.20–2.01, 1.75–1.67, 1.45–1.35, 1.26–1.23 (60 H,
all m, C6H11); dP (162.0 MHz) 35.4 (s).
One-pot synthesis of compound 4.
Method a. Finely divided Mg (10 g, 0.412 mol) in THF
(500 cm3) was activated with 1,2-dichloroethane (10 cm3) and
first PCy3 (36 g, 0.161 mol) and then RuCl3·3H2O (10 g,
38.3 mmol) were added. The mixture was warmed under an
atmosphere of hydrogen and vigorously stirred for 2 h at 65 ◦C
and subsequently for 2 h at 85 ◦C. A red solution was formed and
an orange solid precipitated. The mixture was cooled to −40 ◦C,
and acetylene (1900 cm3, ca. 79 mmol) was introduced by a gas
burette. After the solution was stirred for 5 min at −40 ◦C,
water (2.5 cm3, 0.139 mol) was added. The reaction mixture was
warmed to room temperature and the volatiles were removed in
vacuo. The residue was transferred to a Soxhlet apparatus and
extracted with pentane (800 cm3) for 20 h. After the solvent was
evaporated in vacuo, a light-violet solid was isolated, which was
washed four times with 20 cm3portions of pentane, and dried in
vacuo; yield 22.1 g (76%).
Method b. A suspension of RuCl3·3H2O (1.09 g, 3.95 mmol)
and Na2CO3 (210 mg, 1.98 mmol) in degassed 2-propanol
(150 cm3) was treated with isoprene (4 cm3, 40.0 mmol) and
stirred for 4 h at 85 ◦C. A stepwise change of colour from
red to dark brown and finally to orange-red occurred. After
the suspension was cooled to room temperature, most of the
solvent (ca. 125 cm3) and the excess of isoprene were removed
in vacuo. The remaining suspension was treated with NEt3
=
[RuCl(O2CCF3)( CHCH3)(PCy3)2] 6.
A solution of 2
(116 mg, 0.16 mmol) in CH2Cl2 (5 cm3) was treated with
trifluoroacetic acid (0.012 cm3, 0.16 mmol) at −78 ◦C. A change
of colour from brown to dark red occurred. Since after warming
the solution to room temperature a smooth decomposition of 6
was observed, the product was characterized spectroscopically.
NMR (CD2Cl2, −20 ◦C): dH (200 MHz) 19.85 [1 H, q, J(H,H)
=
=
5.5, Ru CH], 2.61 [3 H, d, J(H,H) 5.5, CHCH3], 2.16 (6 H,
br m, C6H11), 1.91–1.49, 1.25–1.22 (60 H, both m, C6H11); dF
(188.0 MHz) −75.8 (s); dP (81.0 MHz) 36.8 (s).
=
[RuCl(CN)( CHCH3)(PCy3)2] 7. A slow stream of HCN
was passed for ca. 15 s through a solution of 2 (204 mg,
0.28 mmol) in THF (6 cm3) at −78 ◦C. A stepwise change of
colour from brown to red and then from red to orange–brown
occurred. After the solution was warmed to room temperature,
it was concentrated to ca. 1 cm3 in vacuo. Addition of pentane
(4 cm3) led to the precipitation of an orange solid, which was
separated from the mother-liquor, washed three times with
5 cm3 portions of pentane and dried; yield 183 mg (86%);
mp 123 ◦C (decomp.) (Found: C, 62.02; H, 9.08; N, 1.73.
C39H70ClNP2Ru requires: C, 62.34; H, 9.39; N, 1.86%). IR (KBr):
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3
1 8 0 1

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m(CN) 2073 cm−1. NMR (C6D6): dH (400 MHz) 18.25 [1 H, q,
of C6H11), 28.0 (vt, N 10.0, C6H11), 31.1, 26.9 (both s, C6H11),
signal of Ru CH carbon atom not observed; dP (162.0 MHz)
36.6 (s).
=
=
J(H,H) 5.6, Ru CH], 2.73 (6 H, m, C6H11), 2.66 [3 H, d, J(H,H)
5.6, CHCH3], 1.87–1.62, 1.31–1.21, 1.08–1.01 (60 H, all m,
=
=
C6H11); dC (100.6 MHz) 322.1 [t, J(P,C) 6.0, Ru CH], 49.4 (s,
CHCH3), 34.1 (vt, N 19.8, C1 of C6H11), 30.1, 29.7, 26.7 (all s,
C6H11), 27.9 (m, C6H11), signal of CN carbon atom not observed;
Tris(4-tetrahydropyranyl)phosphine P(thp)3 12. In a three-
necked round-bottom flask equipped with a reflux condenser
and a dropping funnel, magnesium filings (1.40 g, 57.6 mmol)
were covered with diethyl ether (5 cm3) and activated by addition
with 1,2-C2H4Br2 (0.65 cm3, 7.70 mmol). After addition of a
second portion of diethyl ether (30 cm3), the slurry was treated
dropwise with a solution of 4-chlorotetrahydropyran (5.40 cm3,
49.89 mmol) in diethyl ether (5 cm3). Parallel to the addition
of the solution of 4-OC5H9Cl, THF (30 cm3) was added in
several portions to the reaction mixture in order to dissolve
the precipitated white solid. The major part of the solvents (ca.
65%) was evaporated in vacuo, and the remaining suspension
was heated for 30 min under reflux. After cooling to room
temperature, the solution containing the Grignard reagent was
filtered and the filtrate was added dropwise to a solu◦tion of
PCl3 (1.31 cm3, 15.0 mmol) in toluene (30 cm3) at −25 C. An
off-white solid precipitated. Toluene (20 cm3) was added, the
mixture was warmed to 50 ◦C and stirred for ◦10 min at this
temperature. The mixture was then cooled to 0 C and treated
with a diluted solution of aqueous HCl (ca. 20 cm3). After the
reaction was finished, three phases separated. The upper organic
phase was withdrawn, and the two lower aqueous phases were
extracted three times with 30 cm3 portions of diethyl ether. To the
aqueous phases diethyl ether (50 cm3) was added and the mixture
was then treated with a concentrated aqueous solution of NH3
as long as the aqueous phase reached pH 9. The ethereal phase
was separated and the aqueous phase was furthermore extracted
twice with 10 cm3 portions of diethyl ether. The combined
ethereal solutions were evaporated in vacuo to give a white solid,
which was recrystallized from acetone; yield 2.28 g (53%), mp
125 ◦C. (Found: C, 62.67; H, 9.20. C15H27O3P requires: C, 62.92;
H, 9.50%). NMR (C6D6): dH (400 MHz) 3.86, 3.15 (6 H each,
both m, OCH2), 1.59 (3 H, m, PCH), 1.51, 1.31 (6 H each,
both m, PCHCH2); dC (100.6 MHz) 68.7 [d, J(P,C) 9.5, OCH2],
31.2 [d, J(P,C) 11.7, PCHCH2], 29.1 [d, J(P,C) 19.2, PCH]; dP
(162.0 MHz) 5.5 (s).
=
dP (162.0 MHz) 42.3 (s).
2
= =
[RuH(j -O2CCF3)( C CH2)(PCy3)2] 8. A solution of 2
(135 mg, 0.19 mmol) in THF (18 cm3) was treated with
CF3CO2K (283 mg, 1.86 mmol) and stirred for 10 min at
room temperature. The solvent was evaporated in vacuo and
the residue was extracted twice with 10 cm3 portions of toluene.
After the combined extracts were brought to dryness in vacuo,
the remaining brown–yellow solid was washed twice with 3 cm3
portions of pentane, and dried in vacuo; yield 129 mg (86%);
mp 44 ◦C (decomp.) (Found: C, 59.48; H, 8.32. C40H69F3O2P2Ru
=
requires: C, 59.91; H, 8.67%). IR (C6H6): m(C C) 2067, m(RuH)
1908, m(OCO)asym 1604, m(OCO)sym 1447 cm−1. NMR (C6D6): dH
=
(400 MHz) 2.72 [2 H, t, J(P,H) 3.2, C CH2], 2.33 (6 H, m,
C6H11), 2.14–2.05, 1.77–1.62, 1.27–1.22 (60 H, all m, C6H11),
−13.16 [1 H, t, J(P,H) 18.4, RuH]; dC (100.6 MHz) 332.9 [t,
=
J(P,C) 14.5, C CH2], 163.1 [q, J(F,C) 37.7, CF3CO2], 114.8 [q,
J(F,C) 287.0, CF3CO2], 86.5 [t, J(P,C) 3.2, C CH2], 34.4 (vt, N
=
19.3, C1 of C6H11), 30.7, 30.0, 27.0 (all s, C6H11), 28.3, 28.2 (both
vt, N 10.0, C6H11); dP (162.0 MHz) 39.2 (s).
= =
[RuHI( C CH2)(PCy3)2] 9. A solution of 2 (158 mg,
0.22 mmol) in THF (4 cm3) was treated with an excess of KI
(500 mg, 3.0 mmol) and stirred for 20 min at room temperature.
The solvent was evaporated in vacuo and the oily residue
was extracted twice with 5 cm3 portions of benzene. After
the combined extracts were brought to dryness in vacuo, the
remaining brown solid was washed three times with 5 cm3
1
portions of pentane, and dried in vacuo; yield 129 mg. The H
and 31P NMR spectra revealed that besides compound 2 some
by-products were formed, which could not be completely re-
moved by fractional crystallization. Data for 2: NMR (CD2Cl2,
−10 ◦C): dH (200 MHz) 2.72 [2 H, t, J(P,H) 3.2, C CH2], 2.64,
=
2.13, 1.93–1.67, 1.28–1.13 (66 H, all m, C6H11), −10.10 [1 H, t,
=
J(P,H) 17.2, RuH]; dC (50.3 MHz) 325.3 [t, J(P,C) 15.0, C CH2],
85.6 (br s, C CH2), 35.6 (vt, N 20.0, C1 of C6H11), 30.6, 29.6,
27.6, 27.3, 26.4 (all s, C6H11); dP (162.0 MHz) 39.2 (s).
=
=
[RuCl2( CHPh){P(thp)3}2] 14. A solution of 13 (350 mg,
0.45 mmol) in CH2Cl2 (10 cm3) was treated with 12 (280 mg,
0.98 mmol) and stirred for 1 h at room temperature. The solvent
was evaporated in vacuo, the light violet residue was washed
three times with 10 cm3 portions of pentane and dried in vacuo;
yield 316 mg (85%); mp 165 ◦C (decomp.) (Found: C, 52.91;
H, 7.03. C37H60Cl2O6P2Ru requires: C, 53.23; H, 7.24%). NMR
=
[Ru(O2CCF3)2( CHCH3)(PCy3)2] 10.
A solution of 8
(82 mg, 0.10 mmol) in THF (5 cm3) was treated dropwise at
◦
−78 C with a solution of CF3CO2H (0.008 cm3, 0.10 mmol)
in THF (2 cm3). After the solution was warmed to room tem-
perature, it was stirred for 10 min. The solvent was evaporated
in vacuo, the light green residue was washed twice with 3 cm3
portions of methanol, and dried in vacuo; yield 105 mg (94%);
mp 64 ◦C (decomp.) (Found: C, 54.85; H, 7.49. C42H70F6O4P2Ru
requires: C, 55.07; H, 7.70%). NMR (C6D6): dH (400 MHz)
=
(CD2Cl2): dH (400 MHz) 20.02 (1 H, s, Ru CH), 8.45 (1 H, m,
C6H5), 7.62 (2 H, m, C6H5), 7.36 (2 H, m, C6H5), 3.91, 3.30 (12
H each, both m, OCH2), 2.91 (6 H, m, PCH), 1.89, 1.61 (12
H each, both m, PCHCH2); dC (100.6 MHz) 299.3 [t, J(P,C)
=
9.0, Ru CH], 153.1, 131.1, 130.8, 129.7 (all s, C6H5), 68.9 (vt,
=
20.91 [1 H, q, J(H,H) 5.2, Ru CH], 2.54 [3 H, d, J(H,H) 5.2,
N 9.0, OCH2), 29.7 (s, PCHCH2), 29.4 (vt, N 18.0, PCH); dP
=
CHCH3], 2.05 (6 H, br m, C6H11), 1.91–1.49, 1.29–1.16 (60 H,
(162.0 MHz) 30.7 (s).
=
both m, C6H11); dC (100.6 MHz) 332.7 [t, J(P,C) 5.0, Ru CH],
164.4 [q, J(F,C) 36.0, CF3CO2], 114.8 [q, J(F,C) 292.0, CF3CO2],
43.5 (br s, CHCH3], 34.4, 29.7 (both br m, C6H11), 27.6, 26.6
(both s, C6H11); dP (81.0 MHz) 38.3 (s).
Catalytic studies
=
In a typical experiment, a mixture of cyclopentene and allyl
alcohol (for exact amounts see Tables 2 and 3) was stirred
at room temperature and treated with 0.02–0.05 mol% of the
catalyst. After a given time a small quantity (0.5 cm3) of the
mixture was removed and diethyl ether (0.5 cm3) was added. A
slow stream of CO was then passed through the solution for ca.
10 s, which led to the de-activation of the catalyst. The amount
and the ratio of the products was then analyzed by GC/MS
using a Hewlett Packard GCD instrument.
=
[RuI2( CHCH3)(PCy3)2] 11. A solution of 4 (380 mg,
0.50 mmol) in THF (20 cm3) was treated with an excess
of NaI (3.0 g, 20.0 mmol) and stirred for 30 min at room
temperature. The solution was filtered, the solvent of the
filtrate was evaporated in vacuo, and the residue was extracted
three times with 20 cm3 portions of methanol. The remaining
light violet solid was dried in vacuo; yield 325 mg (69%); mp 87 ◦C
(decomp.) (Found: C, 48.40; H, 7.55. C38H70I2P2Ru requires: C,
48.36; H, 7.48%). NMR (C6D6): dH (400 MHz) 19.20 [1 H, q,
Crystallography
=
J(H,H) 5.6, Ru CH], 3.41 (6 H, m, C6H11), 2.66 [3 H, d, J(H,H)
=
5.6, CHCH3], 2.10–2.03, 1.78–1.55, 1.37–1.16 (60 H, all m,
Single crystals of 7 were grown from a saturated solution
in pentane which was slowly cooled from room temperature
=
C6H11); dC (100.6 MHz) 58.0 (s, CHCH3), 35.8 (vt, N 19.5, C1
1 8 0 2
D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3

View Article Online
to −20 ◦C; crystal size 0.13 × 0.11 × 0.07 mm, triclinic,
7 M. Christ, S. Sabo-Etienne and B. Chaudret, Organometallics, 1994,
13, 3800; T. Burrow, S. Sabo-Etienne and B. Chaudret, Inorg. Chem.,
1995, 34, 2470.
8 M. Oliva´n, O. Eisenstein and K. G. Caulton, Organometallics, 1997,
16, 2227.
¯
space group P1 (no. 2), a = 10.672(2), b = 11.352(2), c =
◦
˚
˚
19.703(4) A, a = 86.43(3), b = 76.10(3), c = 74.81(3) , V =
◦
3
−3
2236.1(8) A , Z = 2, Dc = 1.219 g cm ; max. 2h = 49.42
˚
[Mo-Ka, k = 0.71073 A, graphite monochromator, x-scan,
9 W. Stu¨er, J. Wolf, H. Werner, P. Schwab and M. Schulz, Angew.
Chem., 1998, 110, 3603; W. Stu¨er, J. Wolf, H. Werner, P. Schwab and
M. Schulz, Angew. Chem., Int. Ed., 1998, 37, 3421.
10 W. Stu¨er, personal communication; see also: J. Wolf, W. Stu¨er, H.
Werner, P. Schwab, M. Schulz (BASF AG), O. Z. 0050/48279, 1997.
11 L. Porri, R. Rossi, P. Deversi and G. Allegra, Tetrahedron Lett., 1965,
4187.
T = 173(2) K], 26086 reflections scanned, 7178 unique [Rint
=
0.0881], 4230 observed [I > 2r(I)], Lorentz polarization and
empirical absorption corrections, Patterson method (SHELXS-
97),30 atomic coordinates and anisotropic thermal displacement
parameters of the non-hydrogen atoms refined anisotropically
by full-matrix least squares on F2 (SHELXL-97),31 carbene
hydrogen atom H(1) found in a differential Fourier synthesis
and refined isotropically, positions of all other hydrogen atoms
calculated according to ideal geometry and refined using the
riding method, one molecule of pentane in the asymmetric unit;
the chloro and the cyano ligands found to be disordered, they
lie in two domains with an occupancy factor of 71 : 29; 464
parameters, reflections/parameter ratio 15.67 : 1, R1 = 0.0529,
3
3
12 An improved synthetic procedure for [RuCl2(g :g -C10H16)]2 has been
reported: D. N. Cox and R. Roulet, Inorg. Chem., 1990, 29, 1360.
13 H. Werner, W. Stu¨er, S. Jung, B. Weberndo¨rfer and J. Wolf,
Eur. J. Inorg. Chem., 2002, 1076.
14 S. Jung, C. D. Brandt, J. Wolf and H. Werner, Dalton Trans., 2004,
375.
15 R. H. Grubbs, S. T. Nguyen, L. K. Johnson, M. A. Hillmyer and
G. Fu (California Institute of Technology, USA), Int. Pat., WO
96/04289, 1996.
16 S. D. Robinson and M. F. Uttley, J. Chem. Soc., Dalton Trans., 1973,
1912; G. B. Deacon and R. J. Phillips, Coord. Chem. Rev., 1980,
33, 227; C. Oldham, in Comprehensive Coordination Chemistry, ed.
G. Wilkinson, R. D. Gillard and J. A. McCleverty, Pergamon Press,
Oxford, 1987, vol. 2, p. 435.
−3
˚
wR2 = 0.1168, residual electron density = 0.716/−995 e A .
CCDC reference number 262120.
See http://www.rsc.org/suppdata/dt/b5/b502440d/ for cry-
stallographic data in CIF or other electronic format.
17 Z. Wu, S. T. Nguyen, R. H. Grubbs and J. W. Ziller, J. Am. Chem.
Soc., 1995, 117, 5503.
Acknowledgements
18 L. D. Quin and M. D. Gordon, J. Am. Chem. Soc., 1976, 98, 15.
19 M. D. Gordon and L. D. Quin, J. Org. Chem., 1976, 41, 1690.
20 J. Schraml, M. Capka and V. Blechta, Magn. Reson. Chem., 1992, 30,
544.
We thank the Deutsche Forschungsgemeinschaft (SFB 347) and
the Fonds der Chemischen Industrie for financial support. We
are also grateful to Mrs R. Schedl, Mr C. P. Kneis (DTA
measurements and elemental analyses), Mrs M.-L. Scha¨fer, Dr
R. Bertermann (NMR spectra), and Degussa AG and BASF AG
for gifts of chemicals. The collaboration with and the support
of Prof. M. Ro¨per and his group at BASF AG is also gratefully
acknowledged.
21 H. Gu¨nther, NMR-Spektroskopie, 3, Georg Thieme Verlag,
Stuttgart, 1992.
22 H. Werner, C. Gru¨nwald, W. Stu¨er and J. Wolf, Organometallics,
2003, 22, 1558.
23 P. Schwab, A. Ho¨hn and R. A. Paciello (BASF AG), Ger. Pat., O. Z.
0050/47116, 1996; P. Schwab, A. Ho¨hn and R. A. Paciello (BASF
AG), Ger. Pat., O. Z. 0050/47400, 1996.
24 E. L. Dias, S. T. Nguyen and R. H. Grubbs, J. Am. Chem. Soc., 1997,
119, 3887.
25 M. S. Sanford, J. A. Love and R. H. Grubbs, J. Am. Chem. Soc.,
2001, 123, 6543; see also: M. S. Sanford and J. A. Love, in Handbook
of Metathesis, ed. R. H. Grubbs, Wiley-VCH, Weinheim, 2003,
vol. 1, p. 112.
26 J. O. Krause, M. T. Zarka, U. Anders, R. Weberskirch, O. Nuyken
and M. R. Buchmeiser, Angew. Chem., 2003, 115, 6147; J. O. Krause,
M. T. Zarka, U. Anders, R. Weberskirch, O. Nuyken and M. R.
Buchmeiser, Angew. Chem., Int. Ed., 2003, 42, 5965.
27 W. Stu¨er, J. Wolf and H. Werner, J. Organomet. Chem., 2002, 641,
203.
28 W. Stu¨er, PhD Thesis, Universita¨t Wu¨rzburg, 1999.
29 M. Oliva´n and K. G. Caulton, Chem. Commun., 1997, 1733.
30 G. M. Sheldrick, SHELXS-97, Universita¨t Go¨ttingen, Go¨ttingen,
Germany, 1997.
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D a l t o n T r a n s . , 2 0 0 5 , 1 7 9 6 – 1 8 0 3
1 8 0 3