Ruthenium(II) complexes containing both arene and functionalized phosphines. Synthesis and catalytic activity for the hydrogenation of styrene and phenylacetylene

Article abstract of DOI:10.1016/S0022-328X(98)00647-0

The [RuCl₂(η⁶-arene)]₂ complex reacts with PPh₂R (R=H, Py, CH₂Py, CCPh, CC^tBu and CCp-Tol) ligands in CH₂Cl₂ to give neutral P-coordinated ruthenium(II) complexes [RuC

Full text of DOI:10.1016/S0022-328X(98)00647-0

Journal of Organometallic Chemistry 566 (1998) 165–174
Ruthenium(II) complexes containing both arene and functionalized
phosphines. Synthesis and catalytic activity for the hydrogenation of
styrene and phenylacetylene
a
a
a,
b
´
Isabel Moldes , Esther de la Encarnacio´n , Josep Ros *, Angel Alvarez-Larena ,
Joan F. Piniella b
a Departament de Qu´ımica, Uni6ersitat Auto`noma de Barcelona, 08193-Bellaterra, Barcelona, Spain
b Unitat de Cristallografia, Uni6ersitat Auto`noma de Barcelona, 08193-Bellaterra, Barcelona, Spain
Received 26 March 1998
Abstract
The [RuCl2(p6-arene)]2 complex reacts with PPh2R (R=H, Py, CH2Py, CꢀCPh, CꢀCtBu and CꢀCp-Tol) ligands in CH2Cl2 to
give neutral P-coordinated ruthenium(II) complexes [RuCl2(p-cymene)PPh2R]. The structure of [RuCl2(p-cymene)PPh2H] and
[RuCl2(p-cymene)PPh2Py] complexes has been established by X-ray diffraction. The neutral P-coordinated complexes [RuCl2(p-
cymene)PPh2Py] and [RuCl2(p-cymene)PPh2CH2Py] react with NaBF4 in CH2Cl2–MeOH mixture to give [RuCl(p6-p-
cymene)PPh2Py]BF4 and [RuCl(p6-p-cymene)PPh2CH2Py]BF4 complexes, in which PPh2Py and PPh2CH2Py act as bidentate
ligands. The structure of [RuCl(p6-p-cymene)PPh2Py]BF4 was determined by X-ray diffraction. The reaction of [RuCl2(p6-arene)]2
with PPh2CꢀCPPh2 led to the [RuCl2(p-cymene)]2PPh2CꢀCPPh2 complex, in which the diphosphine ligand bridges two [RuCl2(p-
cymene)] units. [RuCl2(p-cymene)PPh2Py] and [RuCl(p6-p-cymene)PPh2Py]BF4 are suitable catalyst precursors for the hydrogena-
tion of styrene and phenylacetylene. © 1998 Elsevier Science S.A. All rights reserved.
Keywords: Ruthenium; Arene; Hydrogenation; Phosphine
by dehydrogenation of cyclohexa-1,3- or cyclohexa-1,4-
dienes with ruthenium(III) trichloride in ethanolic solu-
tion [9], but it has been shown recently that a
p6-toluene ruthenium(II) compound can be obtained by
refluxing dichlorotris(triphenylphosphine)ruthenium(II)
in toluene [10]. This result suggests that p6-arene ruthe-
nium(II) species are present in reactions with rutheniu-
m(II) complexes performed in aromatic solvents. In
addition, complexes of type (I) react with Lewis bases
to give neutral [RuCl2(p6-arene)L] (L=Lewis base)
complexes of type (II), which can be converted to
[RuCl2(p6-arene)L]+ complexes of type (III) in polar
solvents when L is a bidentate hemilabile ligand [11,12].
Previous studies of diphenylphosphinoalkynes have
shown both p1-P-coordination [13] and P-coordination
with CꢀC bond activation [14]. The nature of the
y-effects on phosphinoalkynes was also examined in a
1. Introduction
The synthesis and applications of ruthenium(II) com-
plexes have been studied by several authors owing to
their promising roles in catalytic and stoichiometric
reactions. Our group has recently reported the activity
of these complexes in C–C bond formation [1], and in
CO [2], CO2 [3], CS2 [4] and alkyne [5] insertion reac-
tions. Arene ruthenium(II) complexes are very interest-
ing roles as precursors for hydrogenation catalysts [6].
In particular, arene–ruthenium(II) are precursors of
catalysts in asymmetric hydrogenation of h- and i-
functionalized ketones [7,8]. It is well documented that
[RuCl2(p6-arene)]2 complexes (I) are readily prepared
* Corresponding author. Fax: +34 93 5813101; e-mail:
ros@cc.uab.es
0022-328X/98/$19.00 © 1998 Elsevier Science S.A. All rights reserved.
PII S0022-328X(98)00647-0

166
I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
combined experimental and theoretical study on
[Fe(C5H5)(CO)2PPh2CꢀCR]+ systems [15].
Arene Ru(II) complexes catalyze the hydrogenation
of arenes and olefins. In order to extend the study of
such complexes we have prepared a new set of rutheni-
um(II) compounds with PPh2H, PPh2Py, PPh2CH2Py
t
and PPh2CꢀCR (R=Ph, Bu, p-Tol and PPh2). Some
of these ligands were coordinated to arene–Ru(II) frag-
ments in previous studies [17–20]. Our purpose here is
to compare the coordinating abilities of various func-
tionalized phosphines in arene–Ru(II) complexes and
to examine the activity of certain complexes in the
catalytic hydrogenation of styrene and phenylacetylene.
Scheme 2.
ppm in the spectrum of 4. This complex also shows also
a doublet at 4.13 ppm, which can be assigned to
2
1
methylene protons PCH2 with JPH=9.6 Hz. The H-
NMR spectra of diphenylphosphinoalkyne complexes
5–7 are consistent with the monodentate behaviour of
these ligands. The observation of the w(CꢀC) absorp-
tion at 2170–2180 cm−1 in the IR spectra of com-
pounds 5–7 supports this coordination. 13C{1H}-NMR
spectra of complexes 2–7 display resonances that are
consistent with a P-coordination of ligands. It has been
suggested that the chemical shift 13C-NMR differences
(lC2−lC1) of acetylenic carbons for different com-
pounds are related to the triple bond polarization, and
that the sum (lC1+lC2) is associated with the charge
changes [21]. A recent experimental and theoretical
study of [Fe(C5H5)(CO)2PPh2CꢀCR]+ showed that po-
larization of the CꢀC bond is higher than in the free
ligand but lower than in [RPPh2CꢀCR]+ phosphonium
salts [15]. The (lC2−lC1) values for complexes 5–7
are 25.35 (R=CꢀCPh), 44.74 (R=CꢀCtBu) and 29.00
(R=CꢀCp-Tol) ppm, slightly higher than those mea-
sured for the free ligands and significantly lower than
found in [Fe(C5H5)(CO)2PPh2CꢀCR]+ complexes [15].
This difference could be attributed to the neutral nature
of complexes 5–7, which induces a smaller contraction
of molecular distances (including the P–C bond) than
in iron compounds. Otherwise, the (lC2+lC1) values
are similar to those of the diphenylphosphinoalkyne
ligands, which suggests that complexation has no influ-
ence on charge transfer, as found in cationic iron
complexes [15]. 31P{1H}-NMR spectra of 2–7 com-
pounds show the phosphorus resonance as a singlet
between 20 and 30 ppm in complexes 2–4 and between
−2 and −8 ppm in complexes 5–7. These values are
2. Results and discussion
The starting ruthenium(II) complex was [RuCl2(p-
cymene)]2 (1), which was prepared from the reaction of
the commercially available h-phellandrene (5-isopropyl-
2-methylcyclohexa-1,3-diene) with RuCl3 [9]. The reac-
tion of (1) with two equivalents of PPh2R (R=H, Py,
CH2Py, CꢀCPh, CꢀCtBu and CꢀCp-Tol) in CH2Cl2 led
to a family of stable and neutral P-coordinated rutheni-
um(II) complexes [RuCl2(p-cymene)PPh2R] (2–7) in
53–80% yield (Scheme 1). These complexes are highly
soluble in CH2Cl2 and slightly soluble in hexane and
they can be crystallized from CH2Cl2/hexane solutions.
The structure of the P-coordinated complexes (2–7) is
supported by C and H analyses, spectroscopic data (IR
and 1H-, 13C- and 31P-NMR spectroscopy) and the
1
X-ray structure of complexes 2 and 3. H-NMR spectra
of complexes display signals of the p6-p-cymene ligand
together with the resonances of the hydrogens of the
P-coordinated ligands. The arene signals are well re-
solved and show only H–H coupling, as found in
previously reported mononucler p-cymene compounds
[19] and in a recent study on ketophosphines [11]. The
1H-NMR spectrum of 3 shows the signal of the 6-hy-
drogen at 8.79 ppm, whereas this signal appears at 8.94
typical
of
unidentate
P-coordinated
ligands
[18,19,22,23].
The additional coordination of the pyridine nitrogen
atom to ruthenium(II) was found when complexes 3
and 4 were reacted in CH2Cl2 with one equivalent of
NaBF4 dissolved in methanol, which afforded com-
plexes 8 and 9 (Scheme 2). These compounds are highly
soluble in CH2Cl2 and methanol but insoluble in hex-
ane, and they were isolated in 85 and 62% yield,
Scheme 1.

I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
167
Scheme 3.
respectively. The elemental analyses and spectroscopic
lected bonds length and angles and Tables 2–4 display
atomic coordinates of compounds 2, 3 and 8.
data of 8 and 9 are consistent with a molecular formula
[RuCl(p6-p-cymene)L]BF4
(L=PPh2Py
or
Structure of complex 2 is made up by a Ru(II) atom
p6-coordinated to a p-cymene molecule, two chlorine
atoms and to a PPh2H ligand through the P atom
leading to the usual ‘three-legged piano stool’ coordina-
PPh2CH2Py). Their 1H-NMR spectra differ from the
spectra of compounds 3 and 4. First, the 6-hydrogen of
the pyridine group has moved down field and the
methyl hydrogens of the p-cymene ligand are highfield
shifted [19], and secondly, four signals are observed for
the benzene ring hydrogens, as in related compounds
where the metal atom bears four different groups [24].
The 31P{1H}-NMR spectra of complexes 8 and 9 show
resonances at −17.42 and 54.04 ppm, respectively,
which reveal the strong effect of pyridine coordination.
Two signals corresponding to benzene ring carbons of
the p-cymene ligand are also observed in the 13C{1H}-
NMR spectra of compounds 8 and 9.
˚
tion. The Ru–Cl distances (2.416(1) and 2.407(1) A) are
slightly different, as found in related structures with
bulky phosphines [26]. The Ru–C(arene) distances av-
˚
erage 2.214(2) A and the Ru–centroid (p-cymene ring)
˚
length is 1.707(1) A. The arene ring is nearly planar and
shows C–C bond distances that appear to be normal.
The Cl(1)–Ru–Cl(2) of 87.53(2)° is similar to that
found in [RuCl2(p-cymene)PPh2Me], suggesting a simi-
lar steric hindrance [27]. However, Cl(1)–Ru–P and
Cl(2)–Ru–P angles (82.73(2) and 81.42(2)°, respec-
tively) are smaller than those found in similar com-
plexes bearing bulky phosphines [28].
The reaction of [RuCl2(p-cymene)]2 (1) with one
equivalent of bis(diphenylphosphino)acetylene in
CH2Cl2 gave a new orange product 10 (Scheme 3),
which is soluble in CH2Cl2 and partially soluble in
hexane and whose C and H analyses suggest the for-
mula [RuCl2(p-cymene)]2PPh2CꢀCPPh2. The spectro-
scopic data are consistent with a structure in which the
bis(diphenylphosphino)acetylene ligand bridges two
The structure of complex 3 is similar to that of 2. It
consists of a Ru(II) atom p6-bonded to a p-cymene
ligand, to two chlorine atoms and to a monodentate
PPh2Py molecule via the P atom. The geometry of the
molecule is also a ‘three-legged piano stool’. This struc-
˚
ture shows Ru–Cl distances (2.392(2) and 2.520(2) A),
1
[RuCl2(p-cymene)] units. The H- and 13C{1H}-NMR
which are very different. This could be because the
spectra display signals of both arene and diphosphine
ligands. An interesting feature in the 13C-NMR spec-
trum is the doublet at 103.10 ppm (1JCP=76.5 Hz)
which is in agreement with a symmetrical coordination
of bis(diphenylphosphino)acetylene. This hypothesis is
confirmed by the 31P{1H}-NMR spectrum of 10, which
shows only one singlet at 10.13 ppm. On the other hand
the w(CꢀC) absorption is not observed in the IR spec-
trum of compound 10. These spectroscopic data are
coherent with those found in other acetylene bridged
bis(diphenylphosphino)compounds [25].
3. Crystal structures of compounds 2, 3 and 8
Structures of compounds 2 and 3 consists of molecu-
lar units linked by van der Waals forces whereas 8 is
formed by complex cations and BF4− anions joined by
coulombic forces. Figs. 1–3 and Table 1 displays se-
Fig. 1. Molecular structure of the complex [RuCl2(p-
cymene)(PPh2H)] (2).

168
I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
molecule along the Ru–centroid axis are alternate in
complex 2. The angle Cl(1)–Ru–Cl(2) of 92.54(6)° is
larger that found in complex 2 (87.53(2)°) and in other
complexes with bulky phosphines [26]. The P–Ru–
Cl(1) and P–Ru–Cl(2) angles (86.91(5) and 89.09(0)°,
respectively) are also large. The C–C(arene) bond
lengths show non-significant differences with those of
complex 2.
Complex 8 consists of cationic complexes [RuCl(p-
cymene)(PPh2Py)]+ and anions BF4−. The complex
cations contain a Ru(II) atom p6-coordinated to a
p-cymene ring and bonded to a chlorine atom and a
bidentate PPh2Py ligand through N and P atoms. The
˚
Ru–Cl bond of 2.384(2) A is shorter that found in
complexes 2 and 3, which is consistent with the values
reported for other cationic Ru(II) complexes [10]. The
bidentate ligand PPh2Py is p2-bonded through both
˚
pyridinic N atom (Ru–N(36)=2.106(4) A) and the P
˚
atom (Ru–P(1)=2.332(1) A). This last distance is
shorter than that observed in the complex with the
monocoordinated PPh2Py ligand (3). The Ru–N bond
is also shorter than in the Ru(II) complex
[RuCl2(CO)2(PPh2Py)] [22] in spite of having a strong y
acceptor CO ligand trans to the pyridinic N donor
atom. The angles Cl–Ru–P(1) and Cl–Ru–N(36) are
87.54(6) and 83.98(12)°, respectively. The ridigity of the
chelate ligand generates a narrow angle N(36)–Ru–
P(1) of 67.21(13)°. The Ru–C(arene) distances average
Fig. 2. Molecular structure of complex [RuCl2(p-cymene)(PPh2Py)]
(3).
2-pyridyl group is oriented through the Ru atom. The
˚
Ru–N distance of 3.645 A is too long to be considered
as a bond length [29] but the lone pair of electrons of
the N could lengthen the Ru–Cl(2) bond. Otherwise,
˚
the H(6)–N distance of 2.74 A suggests an arene–
˚
pyridine interaction. The Ru–P bond distance of
2.208(5) A, whereas the distance between Ru(II) and
˚
˚
2.364(2) A is quite similar to values reported for similar
the centroid of the arene ring is 1.697(2) A.
P-linked complexes [26,27]. The Ru–C(arene) bond
lengths show small differences, giving a mean distance
˚
of 2.198(4) A. The distance between Ru(II) and the
4. Catalytic properties of compounds 3 and 8
˚
centroid of the arene ring is 1.704(2) A. The relative
Complexes 3 and 8 are catalyst precursors in the
hydrogenation of styrene and phenylacetylene with
molecular hydrogen in dichloromethane solution. Cata-
lytic studies have been performed without addition of
organic bases or coordinating solvents which increase
the catalytic activity of Ru(II) complexes [30]. The
pyridinic N of the bidentate ligand PPh2Py can play the
role of the solvent or the base in catalytic reactions.
Arene Ru(II) complexes are precursors for catalysts of
hydrogenation [16]. In order to complete our study of
PPh2Py containing arene Ru(II) complexes we tested
the catalytic activity of neutral 3 and cationic 8
complexes.
positions of the substituents in a projection of the
Using milder conditions than Bennet applied with the
catalyst [RuClH(C6H6)(PPh3)] ([16]a) (CH2Cl2 solvent;
[complex 3]=5 mM; styrene/complex 3=200; 80°C; 20
atm H2), we detected a 97% conversion of styrene to
ethylbenzene after 80 h. Complex 3 showed no signifi-
cant activity below 80°C and an increase of H2 pressure
did not improve its performance. Cationic complex 8
showed better activity than 3 (CH2Cl2 solvent; [complex
8]=5 mM; styrene/complex 8=200; 80°C; 30 atm H2),
Fig. 3. Molecular structure of the cation [RuCl(p-cymene)(PPh2Py)]+
(8).

I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
169
Table 1
Selected bond lengths (A) and angles (°) for complexes (2), (3) and (8)
˚
[RuCl2(p-cymene)(PPh2H)] (2)
[RuCl2(p-cymene)(PPh2Py)] (3)
[RuCl(p-cymene)(PPh2Py)][BF4] (8)
˚
Bond length (A)
Ru–Cl(1)
Ru–Cl(2)
Ru–P
Ru–C(1)
Ru–C(2)
Ru–C(3)
Ru–C(4)
Ru–C(5)
Ru–C(6)
P–H
2.407(1)
2.416(1)
2.316(1)
2.227(2)
2.240(2)
2.250(2)
2.217(2)
2.175(2)
2.199(2)
1.25(2)
Ru–Cl(1)
Ru–Cl(2)
Ru–P
Ru–C(1)
Ru–C(2)
Ru–C(3)
Ru–C(4)
Ru–C(5)
Ru–C(6)
2.520(1)
2.392(2)
2.364(2)
2.165(4)
2.236(4)
2.269(4)
2.232(3)
2.160(3)
2.126(4)
Ru–Cl
Ru–P
2.384(2)
2.332(1)
2.106(4)
2.200(6)
2.220(6)
2.242(5)
2.225(5)
2.190(4)
2.172(5)
Ru–N(36)
Ru–C(1)
Ru–C(2)
Ru–C(3)
Ru–C(4)
Ru–C(5)
Ru–C6
Bond angle (°)
Cl(1)–Ru–P
Cl(2)–Ru–P
Cl(1)–Ru–Cl(2)
Ru–P–H
82.73(2)
81.42(2)
87.53(2)
Cl(1)–Ru–P
Cl(2)–Ru–P
Cl(1)–Ru–Cl2
86.91(5)
89.09(5)
92.54(6)
Cl–Ru–P
Cl–Ru–N(36)
P–Ru–N(36)
87.54(6)
83.98(12)
67.21(13)
112.05(11)
phenylacetylene/complex=200; 80°C; 20–30 atm H2.
The reaction profile of a run with complex 3 at 30 atm
and 80°C is shown in Fig. 4. Hydrogenation of pheny-
lacetylene to styrene or ethylbenzene did not occur
below 80°. From the reaction profile we can deduce
that:
hydrogenating styrene to ethylbenzene with 94% con-
version after 24 h.
Complexes 3 and 8 are also active species for hydro-
genation of phenylacetylene to styrene and ethylben-
zene. Reaction conditions were: CH2Cl2 solvent;
[complex]=5 mM; phenylacetylene/complex=5 mM;
1. phenylacetylene is hydrogenated faster than styrene,
2. phenylacetylene is hydrogenated to styrene and
ethylbenzene (conversions of 89.3 and 3%, respec-
tively after 15 h),
Table 2
Atomic coordinates (×104) and equivalent isotropic displacement
2
3
˚
parameters (A ×10 ) for 2
3. the alkyne hydrogenation is completed in 25 h and
4. after this time, styrene is hydrogenated to
ethylbenzene
Atom
x
y
z
Ueq
Ru
8354(1)
422(1)
3638(1)
4156(1)
3260(1)
2490(1)
2339(1)
1925(1)
1856(2)
2202(2)
2619(2)
2685(2)
1574(1)
893(2)
33(1)
47(1)
48(1)
36(1)
38(1)
48(1)
60(1)
62(1)
60(1)
49(1)
43(1)
58(1)
74(1)
71(1)
67(1)
53(1)
45(1)
47(1)
43(1)
39(1)
41(1)
45(1)
67(1)
50(1)
82(1)
96(1)
Cl(1)
Cl(2)
P
7442(1)
10049(1)
7279(1)
5530(2)
4978(2)
3646(3)
2875(3)
3423(3)
4744(2)
7815(2)
7172(3)
7604(4)
8633(4)
9274(3)
8868(3)
9714(2)
9618(2)
8423(2)
7242(2)
7347(2)
8570(2)
11016(2)
5972(2)
4785(3)
5920(3)
−1253(1)
−785(1)
−258(1)
−47(2)
875(2)
Reduction of unsaturated substrates to ethylbenzene is
practically complete after 150 h. Cationic rhodium
complexes also show strong catalytic activity in the
hydrogenation of alkynes to cis olefins but the rate of
hydrogenation is greater [31]. Using the same reaction
conditions previously quoted for complex 3, compound
8 hydrogenates phenylacetylene to styrene (85% conver-
sion) in 80 h and to ethylbenzene (99% conversion) in
400 h. It is interesting to note that decreasing the H2
pressure (20 atm) improves the rate of hydrogenation of
phenylacetylene to styrene (90.3% conversion in 24 h)
and decreases the rate of hydrogenation of styrene to
ethylbenzene. In these conditions selective hydrogena-
tion of phenylacetylene to styrene or to ethylbenzene
can be accomplished.
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
1043(3)
299(3)
−610(3)
−788(2)
146(2)
−290(2)
−6(3)
192(2)
169(2)
837(2)
702(3)
1140(3)
854(2)
1539(2)
3793(2)
4534(1)
4787(1)
4326(1)
3603(1)
3341(1)
3515(1)
4650(1)
4088(2)
5336(2)
1892(2)
1409(2)
1254(2)
1563(2)
2049(2)
2226(2)
2037(2)
1393(2)
1565(4)
2193(4)
5. Experimental section
All reactions were performed under dinitrogen using
standard Schlenk techniques. IR spectra were recorded
on a Perkin-Elmer model 1710-FT spectrophotometer
with KBr pellets. The NMR spectra were measured on
C(10)
Ueq is defined as one third of the trace of the orthogonalized Uij
tensor.

170
I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
Table 3
5.1. Synthesis of [RuCl2(p-cymene)(PPh2H)] (2)
Atomic coordinates (×104) and equivalent isotropic displacement
2
3
˚
parameters (A ×10 ) for 3
Diphenyl phosphine (60 mg, 0.32 mmol) was added to
a
dichloromethane solution (20 ml) of complex
Atom
x
y
z
Ueq
[RuCl2(p-cymene)]2 (1) (100 mg, 0.16 mmol). The solu-
tion was stirred for 12 h at r.t. The solvent was re-
moved under vacuum and the residue was washed with
hexane. Crystallization in a dichloromethane/hexane
mixture gave red crystals of 2 (yield 140 mg, 87%).
Anal. Calc. for C22H25Cl2PRu: C, 53.78; H, 4.88.
Found: C, 53.52; H, 5.08%. 1H-NMR (CDCl3 sol.):
7.50 (m, 10H, Ph), 6.44 (d, JPH=412 Hz; 1H, PPh2H),
5.38 (s, 4H, H cym), 2.55 (sept, JHH=6.9 Hz; 1H,
CHMe2), 1.95 (s, 3H, Me), 0.93 (d, JHH=6.9 Hz; 6H,
CHMe2) ppm. 13C{1H}-NMR (CDCl3 sol.): 128.5–
133.4 (Ph), 107.7 (d, JPC=1.5 Hz; CCHMe2), 97.3 (s,
CMe), 88.1 (d, JPC=5.3, CH cym), 85.6 (d, JPC=5.3,
CH cym), 30.3 (s, CHMe2), 21.3 (s, CHMe2), 17.8 (s,
CMe) ppm. 31P{1H}-NMR (CDCl3 sol.): 21.1 (s) ppm.
Ru
P
Cl(1)
Cl(2)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(31)
C(32)
C(33)
C(34)
C(35)
N(36)
2188(1)
3369(1)
−19(1)
1880(2)
2075(3)
1289(3)
1884(3)
3265(3)
4052(3)
3457(3)
1279(8)
3969(6)
5398(9)
4227(9)
5377(2)
6070(3)
7502(4)
8240(3)
7546(4)
6115(4)
3166(3)
4219(3)
3947(4)
2623(4)
1571(3)
1842(3)
2794(5)
2254(6)
1760(7)
1811(7)
2387(7)
2874(6)
4751(1)
4524(1)
6380(2)
2586(2)
6588(3)
5987(4)
4508(4)
3631(3)
4231(3)
5710(3)
8278(5)
1970(5)
811(8)
1860(8)
3591(4)
2108(3)
1493(3)
2360(5)
3843(4)
4459(3)
3499(4)
2883(4)
2320(4)
2373(5)
2989(5)
3551(4)
6393(4)
6789(6)
8247(6)
9310(7)
8823(6)
7418(5)
3735(1)
2243(1)
2328(1)
4040(1)
4046(3)
4765(3)
5486(3)
5488(2)
4769(3)
4048(2)
3297(5)
6329(4)
6188(6)
7513(5)
2663(3)
3357(3)
3729(3)
3405(4)
2710(4)
2339(3)
1508(3)
978(3)
277(3)
105(3)
636(3)
1337(3)
1087(3)
−1(4)
−805(5)
−519(5)
576(5)
33(1)
34(1)
46(1)
49(1)
50(1)
50(1)
45(1)
45(1)
42(1)
41(1)
66(2)
55(2)
77(2)
76(2)
38(1)
50(1)
61(2)
73(2)
60(2)
49(1)
37(1)
46(1)
53(2)
56(2)
59(2)
48(1)
38(1)
48(1)
61(2)
62(2)
60(2)
52(1)
Table 4
Atomic coordinates (×104) and equivalent isotropic displacement
2
3
˚
parameters (A ×10 ) for 8
Atom
x
y
z
Ueq
41(1)
Ru(1)
Cl
P(1)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
475(1)
664(2)
8(1)
1581(1)
−82(1)
8216(1)
9064(1)
8567(1)
7625(6)
8035(6)
7495(5)
6529(5)
6110(4)
6653(5)
8218(8)
5991(6)
5515(7)
4953(8)
7863(4)
6743(5)
6117(6)
6584(6)
7690(6)
8325(5)
8595(4)
7582(7)
7539(8)
8517(7)
9501(7)
9558(5)
65(1)
40(1)
60(1)
66(2)
63(2)
53(1)
50(1)
53(1)
87(2)
63(1)
77(2)
104(3)
43(1)
57(1)
72(2)
71(2)
77(2)
62(1)
43(1)
71(2)
82(2)
86(2)
83(2)
60(1)
47(1)
61(1)
79(2)
81(2)
70(2)
51(1)
70(2)
187(4)
107(2)
155(3)
99(1)
−1901(1)
1205(7)
−1365(4)
−770(5)
135(6)
2497(6)
2518(5)
1222(6)
−40(5)
483(4)
−107(5)
−1023(4)
−2318(5)
1471(5)
−65(6)
1364(4)
C(7)
C(8)
C(9)
1181(11)
1281(7)
Ueq is defined as one third of the trace of the orthogonalized Uij
tensor.
−229(9)
2127(11)
−3152(5)
−4309(6)
−5217(7)
−4963(7)
−3798(8)
−2892(7)
−3106(5)
−3405(7)
−4393(8)
−5072(8)
−4806(8)
−3816(6)
−840(6)
−1192(7)
13(9)
1955(5)
1431(8)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(31)
C(32)
C(33)
C(34)
C(35)
N(36)
B
−1044(3)
−875(4)
−1613(4)
−2524(4)
−2691(4)
−1962(3)
916(3)
a Bruker AC 250 spectrometer in CDCl3 solutions at
room temperature (r.t.) (1H- 250, 13C- 62 and 31P-NMR
102 MHz). Elemental analyses were performed by the
staff of the Chemical Analysis Service at the Universitat
Auto`noma de Barcelona. The gas chromatograph (GC)
analyses for the reaction products of the catalytic reac-
tions were performed on a Hewlett-Packard G1800A
with a flame ionization detector chromatograph using
an HP-5MS (30 m×0.25 mm×0.25 mm) glass capillary
column. The hydrogenation reactions were carried out
in an autoclave with a pressure of H2 in a thermostatic
bath and with magnetic stirring. [RuCl2(p-cymene)]2 [9],
PPh2Py [32], PPh2CH2Py [33] and alkynylphosphines
PPh2CꢀCR (R=Ph, tBu, p-Tol and PPh2CꢀCPPh2) [34]
were prepared according to published procedures. The
preparation of [RuCl2(p-cymene)(PPh2H)] (2) [16] and
[RuCl2(p-cymene)(PPh2CꢀCtBu)] (6) [19] was previously
reported by other authors.
1559(4)
2308(5)
2419(5)
1774(5)
1030(4)
−413(4)
−635(5)
−819(6)
−773(6)
−565(5)
−391(3)
−159(5)
−57(9)
10208(4)
11329(6)
12414(6)
12331(6)
11189(6)
10122(4)
3276(8)
3819(7)
1988(5)
3364(9)
3707(5)
1466(8)
1752(7)
585(5)
6169(9)
F(1)
F(2)
F(3)
F(4)
5045(10)
5476(5)
−268(4)
578(4)
−960(3)
7114(8)
7019(6)
Ueq is defined as one third of the trace of the orthogonalized Uij
tensor.

I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
171
was washed with hexane. The product of the reaction is
an orange oil which can be converted to a solid under
vacuum for several hours (yield 23 mg, 0.40 mmol,
62%). Anal. Calc. for C28H30Cl2NPRu: C, 57.36; H,
5.15; N, 2.40. Found: C, 56.32; H, 5.35; N, 2.44%.
1H-NMR (CDCl3 sol.): 8.98 (m, 1H, py), 7.30 (m, 13H,
Ph+py), 5.29, 5.27, 5.12, 5.11 (4m, 4H, H cym), 4.13
(d, JPH=9.6; 2H, PCH2), 2.50 (sept, JHH=6.9 Hz; 1H,
CHMe2), 1.84 (s, 3H, Me), 0.85 (d, JHH=6.9 Hz; 6H,
CHMe2) ppm. 13C{1H}-NMR (CDCl3 sol.): 155.6 (d,
JPC=13.0 Hz; py), 148.5 (d, JPC=2.5 Hz; py), 135.0–
125.6 (Ph+py), 108.3 (s; CCHMe2), 93.5 (s, CMe), 90.2
(d, JPC=4.6, CH cym), 85.5 (d, JPC=5.5, CH cym),
41.9 (d, JPC=21.1 Hz, CH2), 29.9 (s, CHMe2), 21.4 (s,
CHMe2), 17.3 (s, CMe) ppm. 31P{1H}-NMR (CDCl3
sol.): 29.7 (s) ppm.
5.4. Synthesis of [RuCl2(p-cymene)(PPh2CꢀCR)]
t
[R=Ph (5), Bu (6) and p-Tol (7)]
A total of 100 mg (0.16 mmol) of [RuCl2(p-cymene)]2
(1) were dissolved in 15 ml of methanol and an equimo-
lar amount of the alkynylphosphine (0.16 mmol) was
added. The mixture was stirred for 20 h at r.t. and the
solvent was evaporated to dryness. The residue was
washed several times with hexane and the corresponding
products 5–7 were precipitated as red solids by adding
hexane. Yields were 77 (5), 75 (6) and 60% (7), respec-
tively.
Fig. 4. The hydrogenation of phenylacetylene (CH2Cl2 solvent; [com-
plex 3]=5 mM; phenylacetylene/complex 3=5 mM; pheny-
lacetylene/complex=200; 80°C; 30 atm H2).
5.2. Synthesis of [RuCl2(p-cymene)(PPh2Py)] (3)
5.4.1. Complex 5
A 100 mg (0.16 mmol) sample of complex [RuCl2(p-
cymene)]2 (1) and 100 mg (0.38 mmol) of PPh2Py were
mixed and stirred for 10 h at r.t. in 20 ml of
dichloromethane. The solvent was removed in vacuo
and the residue was washed several times with hexane.
Red crystals of 3 were obtained from crystallization in
a dichloromethane/hexane solution (yield 150 mg, 83%).
Anal. Calc. for C27H28Cl2NPRu: C, 56.98; H, 4.92; N,
Anal. Calc. for C30H29Cl2PRu (CH2Cl2): C, 55.96; H,
4.61. Found: C, 57.26; H, 4.46%. 1H-NMR (CDCl3
sol.): 7.64 (m, 15H, Ph), 5.23, 5.30 (2m, 4H, H cym),
2.90 (sept, JHH=6.9 Hz; 1H, CHMe2), 1.95 (s, 3H, Me),
1.14 (d, JHH=6.9 Hz; 6H, CHMe2) ppm. 13C{1H}-
NMR (CDCl3 sol.): 132.0–128.5 (Ph), 109.5
(CCHMe2), 108.9 (d, JPC=11.1 Hz; CPh), 96.0 (s,
CMe), 90.3 (d, JPC=5.5 Hz; CH cym), 86.6 (d, JPC
=
1
2.46. Found: C, 56.14; H, 5.10; N, 2.49%. H-NMR
5.5, CH cym), 83.5 (d, JPC=88.8 Hz; PPh2C), 30.3 (s,
CHMe2), 22.0 (s, CHMe2), 17.5 (s, CMe) ppm. 31P{1H}-
NMR (CDCl3 sol.): −5.8 (s) ppm. IR (KBr): w(CꢀC)
(CDCl3 sol.): 8.79 (m, 1H, py), 7.30 (m, 10H, Ph), 7.90,
(m, 3H, py), 5.46, 5.42, 5.32, 5.30 (4m, 4H, H cym), 2.53
(sept, JHH=6.9 Hz; 1H, CHMe2), 1.61 (s, 3H, Me), 0.84
(d, JHH=6.9 Hz; 6H, CHMe2) ppm. 13C{1H}-NMR
(CDCl3 sol.): 159,7 (d, JPC=68.1 Hz; py), 148,6 (d,
2169 cm−1
.
5.4.2. Complex 6
JPC=14.8 Hz; py), 123.7 (d, JPC=2.8 Hz; py), 128.5–
Anal. Calc. for C28H33Cl2PRu: C, 58.36; H, 6.26.
Found: C, 58.38; H, 6.50%. 1H-NMR (CDCl3 sol.): 7.30
(m, 10H, Ph), 5.11, 5.20 (2m, 4H, H cym), 2.78 (sept,
133.4 (Ph+py), 109.9 (s; CCHMe2), 94.4 (s, CMe), 91.3
(d, JPC=3.7, CH cym), 85.1 (d, JPC=3.7, CH cym),
29.94 (s, CHMe2), 21.5 (s, CHMe2), 16.8 (s, CMe) ppm.
31P{1H}-NMR (CDCl3 sol.): 20.8 (s) ppm.
J
HH=6.9 Hz; 1H, CHMe2), 1.80 (s, 3H, Me), 1.32 (s,
t
9H, Bu), 1.07 (d, JHH=6.9 Hz; 6H, CHMe2) ppm.
13C{1H}-NMR (CDCl3 sol.): 133.0–128.6 (Ph), 119.5
(d, JPC=9.0 Hz; CtBu), 109.3 (CCHMe2),, 95.5 (s,
5.3. Synthesis of [RuCl2(p-cymene)(PPh2CH2Py)] (4)
CMe), 90.4 (d, JPC=3.6 Hz; CH cym), 86.6 (d, JPC
=
A total of 200 mg (0.33 mmol) of [RuCl2(p-cymene)]2
(1) and 180 mg (0.65 mmol) of PPh2CH2Py were dis-
solved in 20 ml of dichloromethane and stirred for 20 h
at r.t. The solvent was removed in vacuo and the residue
6.2, CH cym), 74.7 (d, JPC=101.6 Hz; PPh2C), 30.2 (s,
CHMe2), 22.0 (s, CHMe2), 17.4 (s, CMe) ppm. 31P{1H}-
NMR (CDCl3 sol.): −7.5 (s) ppm. IR (KBr): w(CꢀC)
2181 cm−1
.

172
I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
5.4.3. Complex 7
(d, JPC=1.0, CH cym), 87.4 (d, JPC=1.4, CH cym),
41.9 (d, JPC=21.1 Hz; CH2),30.7 (s, CHMe2), 21.9 (s,
CHMe2), 22.2 (s, CHMe2), 17.7 (s, CMe) ppm.
31P{1H}-NMR (CDCl3 sol.): 54.0 (s) ppm.
Anal. Calc. for C21H31Cl2PRu: C, 61.40; H, 5.09.
Found: C, 60.40; H, 5.12%. 1H-NMR (CDCl3 sol.):
7.54 (m, 10H, Ph), 7.43 (d, JHH=8.0 Hz; 2H, Tol), 7.13
(d, JHH=8.0 Hz; 2H, Tol), 5.16, 5.24 (2m, 4H, H cym),
2.83 (sept, JHH=6.9 Hz; 1H, CHMe2), 2.31 (s, 3H,
Tol), 1.87 (s, 3H, Me), 1.07 (d, JHH=6.9 Hz; 6H,
CHMe2) ppm. 13C{1H}-NMR (CDCl3 sol.): 133.0–
128.5 (Ph), 117.5 (d, JPC=3.7 Hz; Cp-Tol), 109.2
(CCHMe2), 95.7 (s, CMe), 90.1(s, CH cym), 86.3 (d,
5.7. Synthesis of [RuCl2(p-cymene)(PPh2CꢀCPPh2)]
(10)
A 100 mg (0.16 mmol) sample of [RuCl2(p-cymene)]2
(1) was mixed with 64 mg (0.16 mmol) of
PPh2CꢀCPPh2 in 15 ml of dichloromethane. The mix-
ture was stirred for 20 h at r.t. and the solvent was
evaporated to dryness in vacuo. The residue was
washed several times with hexane and the resulting
solid was crystallized in a dichloromethane–hexane
mixture. Compound 10 was obtained as a red solid
(yield 96 mg, 60%). Anal. Calc. for C46H28Cl2PRu (2
CH2Cl2): C, 48.98; H, 4.42. Found: C, 48.87; H, 4.37%.
1H-NMR (CDCl3 sol.): 7.61 (m, 20H, Ph), 5.31 (m, 8H,
H cym), 2.43 (sept, JHH=6.9 Hz; 2H, CHMe2), 1.70 (s,
6H, Me), 0.94 (d, JHH=6.9 Hz; 12H, CHMe2) ppm.
13C{1H}-NMR (CDCl3 sol.): 133.5–128.3 (Ph), 109.9
(CCHMe2), 103.1 (d, JPC=76.5 Hz; PPh2C), 98.6 (s,
JPC=5.5, CH cym), 88.6 (d, JPC=91.6 Hz; PPh2C),
30.0 (s, CCHMe2), 21.3 (s, Tol), 21.6 (s, CHMe2), 17.2
(s, CMe) ppm. 31P{1H}-NMR (CDCl3 sol.): −2.3 (s)
ppm. IR (KBr): w(CꢀC) 2168 cm−1
.
5.5. Synthesis of [RuCl(p-cymene)(PPh2Py)][BF4] (8)
A solution of 25 mg (0.22 mmol) of NaBF4 in 10 ml
of methanol was added to a solution of 130 mg (0.23
mmol) of compound 3 in 10 ml of dichloromethane.
The mixture was stirred for 10 h at r.t. The solvent was
removed in vacuo, the residue was dissolved in 5 ml of
dichloromethane and filtered off and methanol was
added. Cooling to −20°C induced the formation of
120 mg (85% yield) of compound 8. Anal. Calc. for
C27H28BClF4NPRu: C, 52.25; H, 4.57; N, 2.26. Found:
CMe), 89.1 (d, JPC=4.8 Hz; CH cym), 87.0 (d, JPC
=
3.5, CH cym), 30.2 (s, CHMe2), 21.8 (s, CHMe2), 17.4
(s, CMe) ppm. 31P{1H}-NMR (CDCl3 sol.): 10.1 (s)
ppm. IR (KBr): w(CꢀC) not observed.
1
C, 52.34; H, 4.78; N, 2.37%. H-NMR (CDCl3 sol.):
8.79 (m, 1H, py), 7.30 (m, 10H, Ph), 7.90, (m, 3H, py),
5.46, 5.42, 5.32, 5.30 (4m, 4H, H cym), 2.53 (sept,
5.8. Catalytic hydrogenation reactions
J
J
HH=6.9 Hz; 1H, CHMe2), 1.61 (s, 3H, Me), 0.84 (d,
HH=6.9 Hz; 6H, CHMe2) ppm. 13C{1H}-NMR
All catalytic experiments were performed in a 100 ml
home-built stainless steel autoclave equipped with gas
and liquid inlets, heating device and magnetic stirrer. In
a typical experiment, a solution of the catalyst precur-
sor 3 or 8 (0.1 mmol) and the organic substrate (styrene
or phenylacetylene) (20 mmol) in 20 ml of
dichloromethane was placed into the reactor under
nitrogen and the autoclave was pressurized with H2.
(CDCl3 sol.): 154.9 (d, JPC=16.5 Hz; py), 139.0–128.6
(Ph+py), 111.0 (d, JPC=3.7 Hz; CCHMe2), 101.9 (s,
CMe), 84.8 (d, JPC=1.8 Hz; CH cym), 85.8 (d, JPC
=
1.8 Hz; CH cym), 88.1 (d, JPC=4.6 Hz; CH cym), 88.2
(d, JPC=4.6 Hz; CH cym), 28.9 (s, CHMe2), 22.3 (d,
J
PC=7.3 Hz; CHMe2), 22.6 (d, JPC=7.3 Hz; CHMe2),
18.3 (s, CMe) ppm. 31P{1H}-NMR (CDCl3 sol.): −
17.4 (s) ppm.
5.9. X-ray structure determination and refinement of
complexes 2, 3 and 8
5.6. Synthesis of [RuCl(p-cymene)(PPh2CH2Py)][BF4]
(9)
5.9.1. Crystal data
Following the same procedure and using 150 mg
(0.23 mmol) of [RuCl2(p-cymene)(PPh2CH2Py)] (4), yel-
low crystals of compound 9 were obtained (yield 115
mg, 70%). Anal. Calc. for C28H30BClF4NPRu: C, 52.97;
H, 4.73; N, 2.21. Found: C, 52.85; H, 4.75; N, 1.97%.
1H-NMR (CDCl3 sol.): 9.39 (m, 1H, py), 7.40 (m, 13H,
Ph+py), 5.66, 5.70, 5.78, 5.82 (4m, 4H, H cym), 4.10
(d, JPH=12.4 Hz; 2H, PCH2), 2.63 (sept, JHH=6.9 Hz;
1H, CHMe2), 1.58 (s, 1H, Me), 0.88 (d, JHH=6.9 Hz;
6H, CHMe2) ppm. 13C{1H}-NMR (CDCl3 sol.): 161.9
(d, JPC=2.6 Hz; py), 158.8 (s, py), 140.4–124.5 (Ph+
py), 113.8 (s; CCHMe2), 103.8 (s, CMe), 92.1 (d,
Crystals of 2, 3 or 8 suitable for X-ray diffraction
analysis were obtained by recrystallization in
dichlorometane–hexane mixtures at −20°C.
Compound 2: C22H25Cl2PRu; M=492.36. Mono-
˚
clinic; a=10.394(1), b=11.741(3), c=17.472(2) A,
3
˚
i=97.02(1)°; V=2116.2(6) A (by least-squares refine-
ment on diffractometer angles for 25 automatically
˚
centred reflections, u=0.71069 A), space group P21/c
(no. 14), Z=4; Dcalc. =1.545 g cm−3. Red, air-stable
crystals, v(Mo–Kh)=10.7 cm−1
.
Compound 3: C27H28Cl2NPRu, M=569.44. Tri-
˚
clinic, a=10.514(1), b=10.940(2), c=13.301(2) A,
JPC=3.4, CH cym), 90.9 (d, JPC =3.4, CH cym), 88.1
h=66.80(1), i=88.87(1), k=66.82(1)°, V=1276.0(4)

I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
173
3
˚
A (by least-squares refinement on diffractometer an-
Complex 3: a=0.0629, b=2.75. Final R(F) and
Rw(F2) values were 0.043 and 0.120, respectively, for
reflections with I\2|(I).
Complex 8: a=0.0623, b=0.3336. Final R(F) and
Rw(F2) values were 0.029 and 0.081, respectively, for
reflections with I\2(I).
gles for 25 automatically centred reflections, u=
˚
(
0.71069 A), space group P1 (no. 2), Z=2, Dcalc. =1.482
g cm−3. Red, air-stable crystals, v(Mo–Kh)=9.0 cm−
1.
Compound 8: C27H28BClF4NPRu, M=620.80.
Monoclinic, a=9.227(3), b=14.082(1), c=10.788(1)
3
˚
˚
A, i=106.59(1)°, V=1343.4(5) A (by least-squares
refinement on diffractometer angles for 25 automati-
Acknowledgements
˚
cally centred reflections u=0.71069 A), space group
P21 (no. 4), Z=2, Dcalc. =1.535 g cm−3. Orange,
We thank the Direccio´n General de Investigacio´n
Cient´ıfica y Te´cnica for the financial support (Projects
PB92-0628 and PB96-1146).
air-stable crystals, v=7.9 cm−1
.
5.9.2. Data collection and processing
Data collected on a CAD4 diffractometer, ꢀ−2q
mode with ꢀ scan width=0.80+0.35 tan q, ꢀ scan
speed 1.3–5.5°, graphite monochromated Mo–Kh radi-
ation. Reflection ranges for the data collection were
1BqB25°.
Complex 2: −125h512, 05k513, 05l520. A
total of 3713 unique reflections (Lp and empirical ab-
sorption correction from C-scan [35], min and max
transmission=0.926 and 0.998, respectively), 3311 with
I\2|(I).
Complex 3: −125h512, −115k512, 05l515.
A total of 4303 unique reflections (Lp and empirical
absorption correction from C-scan [35], min and max
transmission=0.938 and 1.000, respectively), 3719 with
I\2|(I).
Complex 8: −105h510, 05k516, 05l512. A
total of 2454 unique reflections (Lp and empirical ab-
sorption correction from C-scan [35], min and max
transmission=0.956 and 0.997, respectively), 2390 with
I\2|(I).
References
[1] M.R. Torres, A. Santos, J. Ros, X. Solans, Organometallics 6
(1987) 1091.
[2] H. Loumhrari, J. Ros, M.R. Torres, A. Santos, A.M. Echavar-
ren, J. Organomet.Chem. 411 (1991) 255.
[3] H. Loumrhari, J. Ros, R. Ya´n˜ez, M.R. Torres, J. Organomet.
Chem. 408 (1991) 233.
[4] M.R. Torres, A. Perales, J. Ros, Organometallics 7 (1988) 1223.
[5] M.R. Torres, A. Vegas, A. Santos, J. Ros, J. Organomet. Chem.
326 (1987) 413.
[6] (a) W.E. Silverthon, Adv. Organomet. Chem. 13 (1975) 48. (b)
H. Le Bozec, D. Touchard, P.H. Dixneuf, Adv. Organomet.
Chem. 29 (1989) 163.
[7] (a) K. Haak, S. Hashiguchi, A. Fujii, Y. Ikarita, R. Noyori,
Angew. Chem. Int. Ed. Engl. 36 (1997) 285. (b) S. Hashiguchi,
A. Fujii, K. Haak, K. Matsumura, T. Ikariya, R. Noyori,
Angew. Chem. Int. Ed. Engl. 36 (1997) 288.
[8] K. Kashima, K. Kusano, N. Sato, et al., J. Org. Chem. 59 (1994)
3064.
[9] M.A. Bennett, G.B. Robertson, A.K. Smith, J. Organomet.
Chem. 43 (1972) C41.
[10] J.R. Polam, L.C. Porter, Inorg. Chim. Acta 205 (1993) 119.
[11] B. Demerseman, R. Le Lagadec, B. Guilbert, C. Renouard, P.
Crochet, P.H. Dixneuf, Organometallics 13 (1994) 2269.
[12] D. Drommi, C.G. Arena, F. Nicolo, G. Bruno, F. Faraone, J.
Organomet. Chem. 485 (1995) 115.
[13] E. Louattani, J. Suades, R. Mathieu, J. Organomet. Chem. 421
(1991) 335.
[14] D. Montllo´, J. Suades, F. Dahan, R. Mathieu, Organometallics
9 (1990) 2933.
[15] E. Louattani, A. Lledo´s, J. Suades, A. Alvarez-Larena, J.F.
Piniella, Organometallics 14 (1995) 1053.
[16] (a) M.A. Bennett, T. Huang, A.K. Smith, T.W. Turney, J.
Chem. Soc. Chem.Commun. (1978) 582. (b) R. Iwata, I. Ogata,
Tetrahedron 29 (1973) 2753.
[17] R. Regragui, P.H. Dixneuf, Organometallics 3 (1984) 1020.
[18] D. Drommi, C.G. Arena, F. Nicolo, G. Bruno, F. Faraone, J.
Organomet. Chem. 485 (1995) 115.
[19] H. Yang, N. Lugan, R. Mathieu, An. Quim. 93 (1997) 28.
[20] D.F. Jones, P.H. Dixneuf, A. Benoit, J. Le Marouille, J. Chem.
Soc. Chem. Commun. (1982) 1217.
5.9.3. Structure analysis and refinement
Direct methods (SHELXS-86 program [36]) and full-
matrix least-squares refinement on F2 for all reflections
(SHELXL-93 program [37]) were applied. Non-H
atoms were refined anisotropically. In compound 3,
p-cymene distances were not sensible when its coordi-
nates were refined freely, probably due to structural
disorder not resolved. The same problem was observed
for a phenyl–P ring. So, benzene rings were refined as
rigid bodies and restraints were applied to p-cymene
geometry. In compound 8, some restrains were also
applied to benzene geometries. Hydrogen atoms were
placed in calculated positions with isotropic tempera-
ture factor fixed at 1.5 (methylic hydrogens) or 1.2 (the
rest) times Ueq for the corresponding carbon atoms.
The weighting scheme was w=1/[|2(Fo2)+(aP)2+bP]
where P=[max(F2o, 0)+2Fc2]/3.
[21] D. Rosenberg, W. Drenth, Tetrahedron 29 (1973) 2753.
[22] M.M. Olmstead, A. Maisonnat, J.P. Farr, A.L. Balch, Inorg.
Chem. 20 (1981) 3877.
[23] C.G. Arena, E. Rotondo, F. Faraone, M. Lanfranchi, A. Tiripic-
chio, Organometallics 10 (1991) 3877.
Complex 2: a=0.0344, b=0.8742. Final R(F) and
Rw(F2) values were 0.021 and 0.061, respectively, for
reflections with I\2|(I).
[24] J.A. Cabeza, P. Maitlis, J. Chem. Soc. Dalton Trans. (1985) 573.

174
I. Moldes et al. / Journal of Organometallic Chemistry 566 (1998) 165–174
[25] E. Louattani, J. Suades, K. Urtiaga, M.I. Arriortua, X. Solans,
Organometallics 15 (1996) 468.
[26] P. Pertici, E. Pitzalis, F. Marchetti, C. Rosini, O. Salvadori,
M.A. Bennet, J. Organomet. Chem. 466 (1994) 221.
[27] M.A. Bennett, G.B. Robertson, A.K. Smith, J. Organomet.
Chem. 43 (1972) C41.
[31] R.R. Schrock, J.A. Osborn, J. Am. Chem. Soc. 98 (1976) 2143.
[32] G.R. Newkome, D.C. Hager, J. Org. Chem. 43 (1978) 947.
[33] M. Alvarez, N. Lugan, R. Mathieu, J. Chem. Soc. Dalton Trans.
(1994) 2755.
[34] A.J. Carty, N-K. Hota, T.W. Ng, H.A. Patel, T.J. O’Connor,
Can. J. Chem. 49 (1971) 2706.
[28] Y. Yamamoto, R. Sato, F. Matsuo, C. Sudoh, T. Igoshi, Inorg.
Chem. 35 (1996) 2329.
[35] A.C.T. North, P.C. Philips, F.S. Mathews, Acta Crystallogr.
Sect. A 24 (1968) 351.
[29] van der Waals radii taken from: J.E. Huheey, E.A. Keiter, R.
Keiter, Inorganic Chemistry, 4th Ed., Harper Collins, p. 292.
[30] T. Ohkuma, H. Ooka, S. Hashiguchi, R. Noyori, J. Am. Chem.
Soc. 117 (1995) 2675.
[36] G.M. Sheldrick, Acta Crystallogr. Sect. A 46 (1990) 467.
[37] G.M. Sheldrick, SHELXL-93, Program for the refinement of
crystal structures from diffraction data, Institut fu¨r Anorg.
Chem., Go¨ttingen, Germany, 1993.
.