Displacement of phenyl and styryl ligands by benzophenone imine and 2-vinylpyridine on ruthenium and osmium

Article abstract of DOI:10.1021/om060222r

The phenyl complexes MPhCl(CO)(PⁱPr₃)₂ (M = Ru (3), Os (4)) have been prepared by reaction of MHCl(CO)(P ⁱPr₃)₂ (M = Ru (1), Os (2)) with HgPh ₂. In solution the phenyl ligand of these compounds rotates around the M-Ph bond. The activation parameters for the process are ΔH? = 13.0 ± 0.6 kcal·mol^-1 and ΔS? = 1.5 ± 1.3 cal·mol^-1·K^-1 for 3 and ΔH? = 11.7 ± 0.5 kcal·mol^-1 and ΔS? = -5.4 ± 1.2 cal·mol^-1·K ^-1 for 4. The addition of benzophenone imine to dichloromethane solutions of 3 and 4 and the related styryl complexes M{(E)-CH=CHPh}Cl(CO) (PⁱPr₃)₂ (M = Ru (7), Os (8)) leads to equilibrium mixtures between the starting compounds and the six-coordinate derivatives MPhCl(NH=CPh₂)(CO)(PⁱPr₃) ₂ (M = Ru (5): ΔH^o = -8.6 ± 0.4 kcal·mol^-1, ΔS^o = -42.5 ± 1.6 cal·mol^-1·K^-1; M = Os (6): ΔH ^o = -9.1 ± 0.8 kcal·mol^-1, ΔS ^o = -31.0 ± 2.6 cal·mol^-1·K ^-1) and M{(E)-CH=CHPh}Cl(NH= CPh₂)(CO)(P ⁱPr₃)₂ (M = Ru (9): ΔH^o = -9.5 ± 0.3 kcal·mol^-1, ΔS^o = -39.4 ± 1.1 cal·mol^-1·K^-1; M = Os (10): ΔH^o = -8.8 ± 0.8 kcal·mol^-1, ΔS^o = -27.3 ± 2.6 cal·mol ^-1·K^-1). In toluene under reflux complexes 3, 4, 7, and 8 react with benzophenone imine and 2-vinylpyridine to afford the metalated derivatives M{C₆H₄C(Ph)=NH}Cl(CO)PⁱPr ₃)₂ (M = Ru (11), Os (12)) and M(NC₅H ₄-o-CH=CH)Cl-(CO)(PⁱPr₃)₂ (M = Ru (13), Os (14)), releasing benzene and styrene. Complexes 9, 12, and 13 have been characterized by X-ray diffraction analysis. The structure of 9 shows a Cl...H-N hydrogen bond (2.47 A) between the NH hydrogen atom of the imine and the chloride ligand.

Full text of DOI:10.1021/om060222r

3076
Organometallics 2006, 25, 3076-3083
Displacement of Phenyl and Styryl Ligands by Benzophenone Imine
and 2-Vinylpyridine on Ruthenium and Osmium
Mar´ıa L. Buil, Miguel A. Esteruelas,* Eva Goni, Montserrat Oliva´n, and Enrique On˜ate
Departamento de Qu´ımica Inorga´nica, Instituto de Ciencia de Materiales de Arago´n,
UniVersidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
ReceiVed March 9, 2006
The phenyl complexes MPhCl(CO)(PiPr3)2 (M ) Ru (3), Os (4)) have been prepared by reaction of
MHCl(CO)(PiPr3)2 (M ) Ru (1), Os (2)) with HgPh2. In solution the phenyl ligand of these compounds
rotates around the M-Ph bond. The activation parameters for the process are ∆Hq ) 13.0 ( 0.6 kcal‚mol-1
and ∆Sq ) 1.5 ( 1.3 cal‚mol-1‚K-1 for 3 and ∆Hq ) 11.7 ( 0.5 kcal‚mol-1 and ∆Sq ) -5.4 ( 1.2
cal‚mol-1‚K-1 for 4. The addition of benzophenone imine to dichloromethane solutions of 3 and 4 and
the related styryl complexes M{(E)-CHdCHPh}Cl(CO)(PiPr3)2 (M ) Ru (7), Os (8)) leads to equilibrium
mixtures between the starting compounds and the six-coordinate derivatives MPhCl(NHdCPh2)(CO)(PiPr3)2
(M ) Ru (5): ∆H° ) -8.6 ( 0.4 kcal‚mol-1, ∆S° ) -42.5 ( 1.6 cal‚mol-1‚K-1; M ) Os (6): ∆H°
) -9.1 ( 0.8 kcal‚mol-1, ∆S° ) -31.0 ( 2.6 cal‚mol-1‚K-1) and M{(E)-CHdCHPh}Cl(NHd
CPh2)(CO)(PiPr3)2 (M ) Ru (9): ∆H° ) -9.5 ( 0.3 kcal‚mol-1, ∆S° ) -39.4 ( 1.1 cal‚mol-1‚K-1; M
) Os (10): ∆H° ) -8.8 ( 0.8 kcal‚mol-1, ∆S° ) -27.3 ( 2.6 cal‚mol-1‚K-1). In toluene under reflux
complexes 3, 4, 7, and 8 react with benzophenone imine and 2-vinylpyridine to afford the metalated
derivatives M{C6H4C(Ph)dNH}Cl(CO)PiPr3)2 (M ) Ru (11), Os (12)) and M(NC5H4-o-CHdCH)Cl-
(CO)(PiPr3)2 (M ) Ru (13), Os (14)), releasing benzene and styrene. Complexes 9, 12, and 13 have been
characterized by X-ray diffraction analysis. The structure of 9 shows a Cl‚‚‚H-N hydrogen bond (2.47
Å) between the NH hydrogen atom of the imine and the chloride ligand.
compounds without rings. In accordance with this, among the
various strategies to stabilize transition metal-carbon bonds,
the chelation-assistance strategy is considered to be one of the
most promising ways.4
As a part of our work on the ability of ruthenium and osmium
hydride complexes to act as templates in carbon-carbon and
carbon-heteroatom coupling reactions,5 we have been exploring
Introduction
A ligand substitution reaction is that in which one Lewis base
displaces another from a Lewis acid. The replacement of one
two-electron donor ligand by another is a fundamental process
in the chemistry of the transition metals. In comparison with
these substitutions, the Lewis base displacement reactions
between one-electron C-donor ligands (eq 1) remain an under-
represented area within coordination chemistry.1
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LnM-R + R′-X f LnM-R′ + R-X
(1)
These M-C metathesis reactions do not involve a change in
the oxidation state of the metal center and have been observed
between alkyl complexes of early transition metals and alkanes.2
Exchanges between alkyl groups and arene substrates by late
metals have also been reported.3
The stability of a complex in which two or more donor atoms
are part of the same ligand often appears much greater than if
the same atoms were in separate ligands. Thus, complexes
containing chelate rings are usually more stable than similar
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* To whom correspondence should be addressed. E-mail: maester@
posta.unizar.es.
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10.1021/om060222r CCC: $33.50 © 2006 American Chemical Society
Publication on Web 05/02/2006

Displacement of Phenyl and Styryl Ligands
Organometallics, Vol. 25, No. 12, 2006 3077
the ability of benzophenone imine,6 aromatic and R,â-unsat-
urated aldehydes and ketones,6c,7 and CH2dEpy (E ) CH, N)
substrates7e,8 to afford cyclometalated derivatives, by means of
C(sp2)-H bond activation reactions with osmium polyhydride
compounds. We now show the ability of benzophenone imine
and 2-vinylpyridine to exchange with phenyl and styryl groups
coordinated to ruthenium and osmium.
This paper reports (i) the preparation and characterization of
the phenyl complexes MPhCl(CO)(PiPr3)2 (M ) Ru, Os),
including the determination of the rotational barrier for the
phenyl group, (ii) the thermodynamic parameters of the
coordination equilibria of benzophenone imine and 2-vinyl-
pyridine to the unsaturated compounds MRCl(CO)(PiPr3)2 (M
) Ru, Os; R ) Ph, CHdCHPh), and (iii) the M-C bond
metathesis reactions between the above-mentioned unsaturated
compounds and the nitrogenated substrates.
Results and Discussion
1. Preparation and Characterization of MPhCl(CO)-
(PiPr3)2 (M ) Ru, Os). These compounds have been synthe-
sized starting from the well-known complexes MHCl(CO)-
(PiPr3)2 (M ) Ru (1), Os (2)),9 by following Roper’s protocol.10
Refluxing 1 and 2 with 1.5 equiv of HgPh2 in toluene for 24 h
gives MPhCl(CO)(PiPr3)2 (M ) Ru (3), Os (4)), which are
isolated as red solids in high yield (81% (3), 72% (4)) according
to eq 2.
Figure 1. (Left) ortho phenyl resonances of RuPhCl(CO)(PiPr3)2
(3) as a function of the temperature. (Right) Simulated spectra.
to the vacant site.12 The ring plane is perpendicular to the
P-M-P direction. This disposition is strongly supported by
the 1H and 13C{1H} NMR spectra. At 223 K in dichloromethane-
d2, the 1H NMR spectra contain five phenyl resonances between
8.5 and 6.5 ppm, whereas in the 13C{1H} NMR spectra six
phenyl signals are observed between 160 and 115 ppm. In
agreement with the mutually trans disposition of the phosphine
ligands, the 31P{1H} NMR spectra show singlets at 35.9 (3)
and 21.3 (4) ppm.
In solution, the phenyl groups of both compounds rotate
around the M-Cipso bond. At 313 K, the processes proceed at
rates sufficient to lead to single ortho phenyl resonances in the
1H NMR spectra (Figure 1 shows the ortho phenyl resonances
of 3 as a function of the temperature). Lowering the sample
temperature produces a broadening of the resonances. Between
283 and 273 K, decoalescence occurs, and at temperatures lower
that 273 K two ortho-phenyl resonances are observed in the
spectra of both compounds.
The spectroscopic data of 3 and 4 agree well with those
previously reported for other ruthenium (II)- and osmium (II)-
aryl derivatives.10,11 Furthermore, they are consistent with a
structure like that of RuPhCl(CO)(PtBu2Me)2, which on the basis
of an X-ray diffraction study has been described as a square-
based pyramidal geometry, with the phenyl group trans disposed
Line-shape analysis of the ortho-phenyl signals allows the
calculation of the rate constants for the rotational processes at
different temperatures. The activation parameters obtained from
the corresponding Eyring analysis are ∆Hq ) 13.0 ( 0.6
kcal‚mol-1 and ∆Sq ) 1.5 ( 1.3 cal‚mol-1‚K-1 for 3 and ∆Hq
) 11.7 ( 0.5 kcal‚mol-1 and ∆Sq ) -5.4 ( 1.2 cal‚mol-1‚K-1
for 4. The values of entropy of activation, close to zero, are in
agreement with intramolecular processes, whereas the values
for the enthalpy of activation are about twice the value obtained
by DFT methods for the rotation of the phenyl group of the
model compound OsHPh(CO)(PH3)2 (6.2 kcal‚mol-1).13 The
calculated barrier underestimates the real value, since the bulky
phosphine ligands must certainly increase it.
2. Formation of Six-Coordinate MRCl(NHdCPh2)(CO)-
(PiPr3)2 (R ) Ph, CHdCHPh; M ) Ru, Os) Complexes. The
addition of benzophenone imine to dichloromethane solutions
of 3 and 4 gives rise to equilibrium mixtures of these compounds
and the six-coordinate derivatives MPhCl(NHdCPh2)(CO)-
(PiPr3)2 (M ) Ru (5), Os (6)), according to eq 3.
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3078 Organometallics, Vol. 25, No. 12, 2006
Buil et al.
Complexes 5 and 6 have been characterized by 1H, 13C{1H},
and 31P{1H} NMR spectroscopy (see Experimental Section).
In accordance with the formation of the new species, at 203 K
in dichloromethane-d2, the 1H NMR spectra of the equilibrium
mixtures show NH resonances at 11.60 (5) and 11.84 (6) ppm,
shifted about 2 ppm toward lower field with regard to the free
ligand. Consistently, the 31P{1H} NMR spectra contain singlets
at 19.5 (5) and -12.0 (6) ppm, which lie 16.4 (5) and 33.3 (6)
ppm toward higher field with regard to 3 and 4, respectively.
Between 188 and 223 K, constants for the equilibria were
determined by integration of the 31P{1H} resonances. Linear-
square analyses of ln K versus 1/T provide values of ∆H° )
-8.6 ( 0.4 kcal‚mol-1 and ∆S° ) -42.5 ( 1.6 cal‚mol-1‚K-1
for 5 and ∆H° ) -9.1 ( 0.8 kcal‚mol-1 and ∆S° ) -31.0 (
2.6 cal‚mol-1‚K-1 for 6.
Figure 2. Molecular diagram of the complex Ru{(E)-CHdCHPh}-
Cl(NHdCPh2)(CO)(PiPr3)2 (9).
Table 1. Selected Bond Lengths (Å) and Angles (deg) for the
Complex Ru{(E)-CHdCHPh}Cl(NHdCPh2)(CO)(PiPr3)2 (9)
Ru-P(1)
Ru-Cl
Ru-C(1)
N-C(9)
N-H(01)
2.4422(8)
2.5159(8)
2.050(3)
1.285(3)
0.82(3)
Ru-P(2)
Ru-N
Ru-C(40)
C(1)-C(2)
2.4392(8)
2.182(2)
1.804(3)
1.329(4)
Similarly to 3 and 4, the styryl complexes M{(E)-CHd
CHPh}Cl(CO)(PiPr3)2 (M ) Ru (7), Os (8)) coordinate benzo-
phenone imine to afford equilibrium mixtures with the six-
coordinate compounds M{(E)-CHdCHPh}Cl(NHdCPh2)(CO)-
(PiPr3)2 (M ) Ru (9), Os (10)), according to eq 4.
P(1)-Ru-P(2)
Cl-Ru-C(1)
N-Ru-C(1)
175.34(3)
88.56(8)
167.23(10)
91.37(12)
Cl-Ru-N
Cl-Ru-C(40)
N-Ru-C(40)
78.69(6)
175.36(9)
101.40(11)
C(1)-Ru-C(40)
hydrogen atoms of the structure, giving a N-H(01) distance of
0.82(3) Å. Interestingly, the separation between H(01) and the
chlorine ligand (2.47 Å) is shorter than the sum of the van der
Waals radii of hydrogen and chlorine (rvdw(H) ) 1.20, rvdw(Cl)
) 1.80 Å),19 suggesting that there is an intramolecular Cl‚‚‚H-N
hydrogen bond between these atoms. The hydrogen bond
approaches the imine to the chlorine atom. Thus, as a result of
this, the N-Ru-Cl angle (78.69(6)°) largely deviates from the
ideal value of 90°. Of great importance in biological and organic
chemistry,20 the hydrogen bonding is presently attracting
considerable interest in the chemistry of transition metals.6c,15c,21
Crystallization of the mixture of 7 and 9 in toluene at 193 K
affords crystals of the latter suitable for an X-ray diffraction
study. Figure 2 shows the structure of this complex, whereas
selected bond distances and angles are listed in Table 1. The
geometry around the metal can be rationalized as a distorted
octahedron with the two phosphorus atoms of the phosphine
ligands occupying opposite positions (P(1)-Ru-P(2) )
175.34(3)°). The perpendicular plane is formed by the imine
trans disposed to the styryl ligand (N-Ru-C(1) ) 167.23(10)°)
and the chlorine trans disposed to the carbonyl group (Cl-
Ru-C(40) ) 175.36(9)°).
The imine is bound to the ruthenium atom in a bent fashion,
with a Ru-N-C(9) angle of 149.2(2)°. The Ru-N bond length
of 2.182(2) Å supports the single bond formulation.14 The
N-C(9) distance of 1.285(3) Å is similar to those observed in
other imine transition metal complexes,15 azavinylidene com-
pounds,16 organic azaallenium cations,17 and 2-azaallenyl com-
plexes.18
The styryl ligand shows a trans disposition for the two
substituents, C6H5 and RuCl(CO)(NHdCPh2)(PiPr3)2, at the
C-C double bond. The Ru-C(1) distance (2.050(3) Å) and
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122, 357. (c) Esteruelas, M. A.; Go´mez, A. V.; Lahoz, F. J.; Lo´pez, A. M.;
On˜ate, E.; Oro, L. A. Organometallics 1996, 15, 3423. (d) Jime´nez-Tenorio,
M.; Palacios, M. D.; Puerta, M. C.; Valerga, P. J. Organomet. Chem. 2004,
689, 2776.
(19) Barrio, P.; Esteruelas, M. A.; Lledo´s, A.; On˜ate, E.; Toma`s, J.
Organometallics 2004, 23, 3008.
(20) Jeffrey, G. A.; Saenger, W. Hydrogen Bonding in Biological
Structures; Springer: Berlin, 1991.

Displacement of Phenyl and Styryl Ligands
Organometallics, Vol. 25, No. 12, 2006 3079
Scheme 1
the C(1)-C(2) bond length (1.329(4) Å) support the alkenyl
formulation for the complex.22
At 193 K in dichloromethane-d2, the 1H, 13C{1H}, and
31P{1H} NMR spectra of 9 and 10 are consistent with the
structure shown in Figure 2. In agreement with the presence of
the coordinated imine ligand and with the spectra of 5 and 6,
1
the H NMR spectra contain broad singlets at 11.26 (9) and
11.46 (10) ppm. These chemical shifts compare well with that
of the complex OsH2(SnPh2Cl){C6H4C(Ph)dNH}(PiPr3)2 (δ
12.8)6c and suggest that at 193 K the Cl‚‚‚H-N interaction is
retained in dichloromethane. The CHR and CHâ resonances of
the styryl ligand are observed at 9.01 (9) and 9.46 (10), and
6.36 (9) and 6.38 (10) ppm, respectively. In accordance with
the trans disposition at the C-C double bond, the H-H
coupling constants are 16.5 (9) and 13.8 (10) Hz. In the 13C{1H}
NMR spectra, the CR and Câ resonances of the alkenyl ligand
appear at 160.5 (9) and 143.1 (10), and 136.8 (9) and 135.2
(10) ppm, respectively. The 31P{1H} NMR spectra show singlets
at 21.1 (9) and -10.2 (10) ppm, shifted 16.6 and 35.5 ppm,
respectively, toward higher field with regard to 7 (δ 37.7) and
8 (δ 33.5).23
The thermodynamic parameters for the equilibria shown in
eq 4 have also been determined in a manner similar to those
for the equilibria shown in eq 3, by integration of the 31P{1H}
NMR resonances. The values obtained, ∆H° ) -9.5 ( 0.3
kcal‚mol-1 and ∆S° ) -39.4 ( 1.1 cal‚mol-1‚K-1 for 9 and
∆H° ) -8.8 ( 0.8 kcal‚mol-1 and ∆S° ) -27.3 ( 2.6
cal‚mol-1‚K-1 for 10, agree well with those obtained for 5 and
6.
respectively. Since at 111 °C, the toluene reflux temperature,
the amounts of ruthenium in six-coordinate form are less than
0.06% and those of osmium are less than 9%, it appears to be
reasonable to think that the formation of 11 and 12 takes place
from the five-coordinate compounds 3, 4, 7, and 8, according
to Scheme 1, without the participation of 5, 6, 9, and 10. In
addition, it should be noted that, in contrast to 5, 6, 9, and 10,
complexes 3, 4, 7, and 8 are 16-electron valence species. This
unsaturated character allows the ortho-CH bond oxidative
addition of one of the phenyl groups of the imine. Thus, the
subsequent reductive elimination of benzene or styrene, followed
by the coordination of the iminic nitrogen atom to the metal
center, could afford the products of these unusual σ-bond
metathesis processes. The driving force for the substitutions is
certainly the chelate nature of the resulting ligand from the
displacements.
According to the values of ∆H° and ∆S° calculated for the
equilibria shown in eqs 3 and 4, the formation constant of the
six-coordinate species at 20 °C increases in the sequence 5 (1.4
× 10-3) < 9 (2.8 × 10-3) < 6 (0.96) < 10 (3.8), i.e., Ru < Os
and Ph < CHdCHPh. These results elegantly prove that the
trans influence of phenyl is higher that that of styryl and that
the coordination power of osmium(II) is stronger than that of
ruthenium(II).
Complexes 11 and 12 are isolated as yellow (11) and pink
(12) solids in high yields (80-85%) and were characterized by
MS, elemental analysis, IR, and 1H, 13C{1H}, and 31P{1H} NMR
spectroscopy. Complex 12 was further characterized by an X-ray
crystallographic study. A view of the molecular geometry of
this compound in shown in Figure 3. Selected bond distances
and angles are listed in Table 2.
The coordination geometry around the osmium atom can be
rationalized as derived from a distorted octahedron with the two
phosphorus atoms of the triisopropylphosphine ligands occupy-
ing trans positions (P(1)-Os-P(2) ) 173.986(19)°). The
perpendicular plane is formed by the atoms C(1) and N of the
orthometalated benzophenone imine ligand, which acts with a
bite angle of 76.73(8)°, the chlorine trans disposed to C(1) (Cl-
3. Phenyl- and Styryl-Phenyl Exchanges. In toluene under
reflux, the equilibrium mixtures shown in eqs 3 and 4 evolve
into the orthometalated complexes M{C6H4C(Ph)dNH}Cl(CO)-
PiPr3)2 (M ) Ru (11), Os (12)), releasing benzene and styrene,
(21) See for example: (a) Stevens, R. C.; Bau, R.; Milstein, D.; Blum,
O.; Koetzle, T. F. J. Chem. Soc., Dalton Trans. 1990, 1429. (b) Lough; A.
J.; Park, S.; Ramachandran, R.; Morris, R. H. J. Am. Chem. Soc. 1994,
116, 8356. (c) Peris, E.; Lee, J. C., Jr.; Rambo, J. R.; Eisenstein, O.; Crabtree,
R. H. J. Am. Chem. Soc. 1995, 117, 3485. (d) Crabtree, R. H.; Eisenstein,
O.; Sini, G.; Peris, E. J. Organomet. Chem. 1998, 567, 7. (e) Crabtree, R.
H. J. Organomet. Chem. 1998, 557, 111. (f) Gusev, D. G.; Lough, A. J.;
Morris, R. H. J. Am. Chem. Soc. 1998, 120, 13138. (g) Buil, M. L.;
Esteruelas, M. A.; On˜ate, E.; Ruiz N. Organometallics 1998, 17, 3346. (h)
Esteruelas, M. A.; Oliva´n, M.; On˜ate, E.; Ruiz, N.; Tajada, M. A.
Organometallics 1999, 18, 2953. (i) Lee, D.-H.; Kwon, H. J.; Patel, B. P.;
Liable-Sands, L. M.; Rheingold, A. L.; Crabtree, R. H. Organometallics
1999, 18, 1615. (j) Clot, E.; Eisenstein, O.; Crabtree, R. H. New J. Chem.
2001, 25, 66. (k) Barrio, P.; Esteruelas, M. A.; On˜ate, E. Organometallics
2002, 21, 2491.
(22) See for example: (a) Esteruelas, M. A.; Liu, F.; On˜ate, E.; Sola,
E.; Zeier, B. Organometallics 1997, 16, 2919. (b) Cannadine, J. C.; Hill,
A. F.; White, A. J. P.; Williams, D. J.; Wilton-Ely, J. D. E. T. Organo-
metallics 1996, 15, 5409. (c) Wilton-Ely, J. D. E. T.; Wang, M.; Honarkhah,
S. J.; Tocher, D. A. Inorg. Chim. Acta 2005, 358, 3218. (d) Wilton-Ely, J.
D. E. T.; Pogorzelec, P. J.; Honarkhah, S. J.; Reid, D. H.; Tocher, D. A.
Organometallics 2005, 24, 2862. (e) Dewhurst, R. D.; Hill, A. F.; Smith,
M. K. Organometallics 2005, 24, 6295. (f) Wilton-Ely, J. D. E. T.;
Honarkhah, S. J.; Wang, M.; Tocher, D. A.; Slawin, A. M. Z. Dalton Trans.
2005, 1930.
Figure 3. Molecular diagram of the complex Os{C6H4C-
(Ph)dNH}Cl(CO)(PiPr3)2 (12).
(23) Werner, H.; Esteruelas, M. A.; Otto, H. Organometallics 1986, 5,
2295.

3080 Organometallics, Vol. 25, No. 12, 2006
Buil et al.
Table 2. Selected Bond Lengths (Å) and Angles (deg) for the
Scheme 2
Complex Os{C6H4C(Ph)dNH}Cl(CO)(PiPr3)2 (12)
Os-P(1)
Os-Cl
Os-C(1)
N-C(7)
2.4144(6)
2.5143(6)
2.038(2)
1.296(3)
Os-P(2)
Os-N
Os-C(32)
N-H(01)
2.4215(6)
2.1041(18)
1.844(2)
0.75(2)
P(1)-Os-P(2)
Cl-Os-C(1)
N-Os-C(1)
173.986(19)
164.47(6)
76.73(8)
Cl-Os-N
87.75(5)
102.50(7)
169.75(8)
119.18(15)
Cl-Os-C(32)
N-Os-C(32)
Os-N-C(7)
C(1)-Os-C(32)
93.02(9)
Os-C(1)) ) 164.47(6)°) and the carbonyl group trans located
to the nitrogen atom (C(32)-Os-N )169.75(8)°).
The five-membered ring formed by the metalated imine and
the osmium atom is almost planar. The Os-N bond length of
2.1041(18) Å and the Os-C(1) distance of 2.038(2) Å are
typical for Os-N and Os-C(aryl) single bonds, respectively,
and are in agreement with the values previously found for
derivatives. The larger steric requirement of 2-vinylpyridine with
regard to benzophenone imine prevents the coordination of the
nitrogen atom of the pyridine ring to the coordination vacancy
of the five-coordinate compounds. However, in toluene under
reflux these compounds react with 2-vinylpyridine to afford the
the complexes [OsH(η5-C5H5){C6H4C(Ph)dNH}(PiPr3)]BF4
metalated complexes M(NC5H4-o-CHdCH)Cl(CO)(PiPr3)2 (M
) Ru (13), Os (14)) and benzene (3 and 4) or styrene (7 and
8), as result of phenyl- and styryl-vinyl metathesis reactions
(Scheme 2). These processes can be rationalized in a manner
similar to the previously mentioned phenyl- and styryl-phenyl
exchanges; that is, the oxidative addition of one of the terminal
C(sp2)-H bonds of the vinyl substituent of the pyridine to the
ruthenium and osmium centers of 3, 4, 7, and 8, followed by
the reductive elimination of benzene or styrene and the
subsequent coordination of the pyridinic nitrogen atom to the
metal centers, should give 13 and 14.
(2.078(18) and 2.080(19) Å, and 2.10(2) and 2.137(19) Å),24
Os{C6H4C(Ph)dNH}Cl(η2-H2)(PiPr3)2 (2.097(3) and 2.069(4)
Å),6a Os{C6H4C(Ph)dNH}(C2Ph)(CO)(PiPr3)2 (2.106(7) and
2.089(7) Å),25 [Os{C6H4C(Ph)dNH}(η6-C6H3Me3)(PiPr3)]-
PF6 (2.083(4) and 2.072(4) Å),26 OsH{(C6H3-p-Me)C(p-
tolyl)dNNdC(p-tolyl)2}(CO)2(PPh3) (2.119(5) and 2.100(7)
Å),27 fac-Os{C,N-3-Me[2-(MeC6H4)NCMe3]C6H3}(2-MeC6H4)-
(CN-tBu)3 (2.193(24) and 2.077(20) Å),28 OsH2(SnPh2Cl)-
These compounds are isolated as yellow (13) and orange (14)
solids in high yields (70-76%) and were characterized by MS,
{C6H3C(Ph)dNH}(PiPr3)2 (2.094(3) and 2.108(4) Å), and
1
elemental analysis, IR, and H, 13C{1H}, and 31P{1H} NMR
OsH2(SnPh2OH){C6H4C(Ph)dNH}(PiPr3)2 (2.102(5) and 2.114(5)
Å).6c The N-C(7) distance of 1.296(3) Å is similar to that
observed in 9 and agrees well with those found in other
orthometalated imine complexes.29
spectroscopy. Complex 13 was further characterized by an X-ray
crystrallographic study. The structure has two chemically
equivalent but crystallographically independent molecules in the
asymmetric unit. A drawing of one of them is shown in Figure
4. Selected bond distances and angles for both molecules are
listed in Table 3.
1
The H, 13C{1H}, and 31P{1H} NMR spectra of 11 and 12
1
are consistent with the structure shown in Figure 3. In the H
NMR spectra, the most noticeable resonances are those corre-
sponding to the NH protons, which, as a consequence of the
absence of Cl‚‚‚H-N hydrogen bonds, appear at 9.56 (11) and
9.40 (12) ppm, shifted about 2 ppm toward higher field with
regard to 5, 6, 9, and 10. In the 13C{1H} NMR spectra, the
resonances due to the metalated carbon atom of the imine are
observed at 191.9 (11) and 193.8 (12) ppm, as triplets with C-P
coupling constants of 8.3 and 9.1 Hz, respectively. The 31P{1H}
NMR spectra show singlets at 36.1 (11) and 3.0 (12) ppm.
4. Phenyl- and Styryl-Vinyl Exchanges. In contrast to
benzophenone imine, the addition of 2-vinylpyridine to toluene-
d8 or dichloromethane-d2 solutions of 3, 4, 7, and 8 does not
give rise to the formation of the corresponding six-coordinate
The coordination geometry around the osmium atom can be
rationalized as a distorted octahedron with the two phosphorus
atoms of the triisopropylphosphine ligands occupying mutually
trans positions (P(1)-Ru(1)-P(2) ) 172.95(6)° molecule a and
(24) Esteruelas, M. A.; Gutie´rrez-Puebla, E.; Lo´pez, A. M.; On˜ate, E.;
Tolosa, J. I. Organometallics 2000, 19, 275.
(25) Esteruelas, M. A.; Lahoz, F. J.; Lo´pez, A. M.; On˜ate, E.; Oro, L.
A. Organometallics 1995, 14, 2496.
(26) Werner, H.; Daniel, T.; Braun, T.; Nu¨rnberg, O. J. Organomet.
Chem. 1994, 480, 145.
(27) Gallop, M. A.; Rickard, C. E. F.; Roper, W. F. J. Organomet. Chem.
1990, 395, 333.
(28) Arnold, J.; Wilkinson, G.; Hussain, B.; Hursthouse, M. B. Organo-
metallics 1989, 8, 1362.
(29) See for example: (a) Becalski, A. G.; Cullen, W. R.; Fryzuk, M.
D.; James, B. R.; Kang, G. J.; Rettig, S. J. Inorg. Chem. 1991, 30, 5002.
(b) Ezhova, M. B.; Patrick, B. O.; Sereviratne, K. N.; James, B. R.; Ford,
M. E.; Waller, F. J.; Ford, M. E. Inorg. Chem. 2005, 44, 1482. (c) Ezhova,
M. B.; Patrick, B. O.; James, B. R. Organometallics 2005, 24, 3753.
Figure 4. Molecular diagram of the complex Ru(NC5H4-o-
CHdCH)Cl(CO)(PiPr3)2 (13).

Displacement of Phenyl and Styryl Ligands
Organometallics, Vol. 25, No. 12, 2006 3081
Cl(NHdCPh2)(CO)(PiPr3)2, where the NH hydrogen atoms of
the imines and the chlorine ligands are involved in Cl‚‚‚H-N
hydrogen bonds. The values of ∆H° and ∆S° for these equilibria
prove that the trans influence of phenyl is higher than that of
styryl and that the coordination power of osmium(II) is stronger
than that of ruthenium(II).
Table 3. Selected Bond Lengths (Å) and Angles (deg) for the
Complex Ru{(E)-Ru(NC5H4-o-CHdCH)Cl(CO)(PiPr3)2 (13)
molecule a
molecule b
Ru(1)-P(1)
Ru(1)-P(2)
Ru(1)-Cl(1)
Ru(1)-N(1)
Ru(1)-C(7)
Ru(1)-C(8)
C(6)-C(7)
2.4214(18) Ru(2)-P(3)
2.4315(17) Ru(2)-P(4)
2.4183(19)
2.4232(18)
2.5122(17)
2.172(6)
2.003(7)
1.827(7)
2.5090(16) Ru(2)-Cl(2)
In toluene under reflux, these five-coordinate complexes react
with benzophenone imine and 2-vinylpyridine to afford the
2.157(5)
2.009(7)
1.798(6)
1.343(9)
Ru(2)-N(2)
Ru(2)-C(33)
Ru(2)-C(34)
C(32)-C(33)
metalated derivatives M{C6H4C(Ph)dNH}Cl(CO)(PiPr3)2 and
1.347(10)
M(NC5H4-o-CHdCH)Cl(CO)(PiPr3)2 (M ) Ru, Os), as a
consequence of novel phenyl-phenyl, styryl-phenyl, phenyl-
vinyl, and styryl-vinyl exchanges. Although the driving force
for these displacements is undoubtedly the chelate character of
the metalated nitrogen donor ligands, it should be mentioned
that the thermodynamic parameters for the coordination equi-
libria of benzophenone imine to the five-coordinate starting
compounds and the fact that the latter complexes do not
coordinate 2-vinylpyridine suggest that six-coordinate species
of the type MRClL(CO)(PiPr3)2 (L ) NHdCPh2, NC5H4-o-
CHdCH2) are not involved in the ligand exchanges. It seems
that the carbon-carbon replacements occur before the coordina-
tion of the nitrogen atoms.
P(1)-Ru(1)-P(2)
172.95(6)
P(3)-Ru(2)-P(4)
Cl(2)-Ru(2)-N(2)
N(2)-Ru(2)-C(33)
N(2)-Ru(2)-C(34)
Cl(2)-Ru(2)-C(33)
Cl(2)-Ru(2)-C(34)
C(33)-Ru(2)-C(34) 91.0(3)
Ru(2)-C(33)-C(32) 116.8(5)
C(31)-C(32)-C(33) 118.3(7)
175.27(7)
89.99(15)
78.1(3)
169.0(3)
168.1(2)
101.0(3)
Cl(1)-Ru(1)-N(1) 90.89(14)
N(1)-Ru(1)-C(7)
N(1)-Ru(1)-C(8)
Cl(1)-Ru(1)-C(7) 167.5(2)
Cl(1)-Ru(1)-C(8) 102.0(2)
C(7)-Ru(1)-C(8)
Ru(1)-C(7)-C(6)
C(5)-C(6)-C(7)
76.9(3)
166.8(3)
90.4(3)
118.2(6)
116.8(7)
175.27(7)° molecule b). The ruthenium sphere is completed by
the metalated group, which acts with bite angles of 76.9(3)°
(a) and 78.1(3)° (b), the chlorine ligand trans disposed to C(7)
(C(7)-Ru(1)-Cl(1) ) 167.5(2)° (a) and 168.1(2)° (b)), and
the carbonyl group trans disposed to N(1) (C(8)-Ru(1)-N(1)
) 166.8(3)° (a) and 169.0(3)° (b)).
In conclusion, using the chelation-assistance strategy, we have
achieved novel C(sp2)/C(sp2) metathesis reactions on ruthenium
and osmium.
The Ru(1)-C(7) bond lengths of 2.009(7) Å (a) and 2.003(7)
Å (b) are as expected for a Ru-C(sp2) single bond and similar
to the ruthenium-styryl distance in 9. The C(7)-C(6) bond
lengths of 1.343(9) and 1.347(10) Å also agree with the related
parameter in 9 and with the average carbon-carbon double bond
distances in vinyl groups (1.35(2) Å).30 In accordance with the
sp2 hybridization at C(6) and C(7), the angles C(5)-C(6)-C(7)
and Ru(1)-C(7)-C(6) are 116.8(7)° (a) and 118.3(7)° (b), and
118.2(6)° (a) and 116.8(5)° (b), respectively.
Experimental Section
All reactions were carried out under an argon atmosphere using
Schlenk tube techniques. Solvents were dried and purified by known
procedures and distilled under argon prior to use. Complexes MHCl-
(CO)(PiPr3)2 (M ) Ru (1), Os (2))9a and M{(E)-CHdCHPh}Cl-
(CO)(PiPr3)2 (M ) Ru (8), Os (9))23 were prepared as previously
described. Infrared spectra were recorded on a Perkin-Elmer
1
The H, 13C{1H}, and 31P{1H} NMR spectra of 13 and 14
1
Spectrum One spectrometer as solids (Nujol mull). H, 13C{1H},
1
are consistent with the structure shown in Figure 4. In the H
and 31P{1H} NMR spectra were recorded on either a Varian Gemini
2000, a Bruker AXR 300, and a Bruker Avance 400 instrument.
Chemical shifts are referenced to residual solvent peaks (1H and
13C{1H}) or external H3PO4 (31P{1H}). Coupling constants J and
NMR spectrum in benzene-d6 the MCH resonances of the vinyl
group appear at 9.81 (13) and 10.63 (14) ppm as doublets with
H-H coupling constants of about 8 Hz, whereas the HC-py
resonances are observed at 6.78 (13) and 7.01 (14) ppm. The
13C{1H} NMR spectra agree well with those of other transition
metal compounds containing a metalated 2-vinylpyridine ligand.31
In this context, it should be mentioned that the chemical shifts
of the MC signals (δ, 200.4 (13) and 184.8 (14)) indicate a low
contribution of the carbene resonance form at the metal-vinyl
bonds.32 The 31P{1H} NMR spectra show singlets at 32.3 (13)
and 0.8 (14) ppm.
1
N (N ) JP-H + JP′-H for H; N ) JP-C + JP′-C for 13C{1H}) are
given in hertz. C, H, and N analyses were measured on a Perkin-
Elmer 2400 CHNS/O analyzer.
Preparation of RuPhCl(CO)(PiPr3)2 (3). A solution of 1 (250
mg, 0.52 mmol) and HgPh2 (277 mg, 0.78 mmol) in toluene (15
mL) was heated at reflux for 24 h. After this time it was filtered
through Celite and evaporated to dryness. The addition of methanol
caused the formation of a brick red solid, which was washed with
methanol and dried in vacuo. Yield: 234 mg (81%). Anal. Calcd
for C25H47ClP2Ru: C, 53.42; H, 8.43. Found: C, 53.15; H, 8.69.
Concluding Remarks
1
IR (Nujol, cm-1): ν(CO) 1906 (s). H NMR (400 MHz, CD2Cl2,
In dichloromethane, the five-coordinate complexes MPhCl-
(CO)(PiPr3)2 and M{(E)-CHdCHPh}Cl(CO)(PiPr3)2 (M ) Ru,
Os) coordinate benzophenone imine to give equilibrium mixtures
between the starting compounds and the six-coordinate deriva-
tives MPhCl(NHdCPh2)(CO)(PiPr3)2 and M{(E)-CHdCHPh}-
223 K): δ 7.76 (d, JH-H ) 7.6, 1H, o-Ph), 7.07 (d, JH-H ) 7.6,
1H, o-Ph), 6.63-6.56 (m, 3H, Ph), 2.57 (m, 6H, PCH), 1.13 (dvt,
N ) 13.5, JH-H ) 7.2, 18H, PCH(CH3)2), 0.98 (dvt, N ) 13.8,
JH-H ) 7.2, 18H, PCH(CH3)2). 31P{1H} NMR (121.42 MHz,
CD2Cl2, 293 K): δ 35.9 (s). 13C{1H} NMR (100.56 MHz, CD2Cl2,
223 K): δ 204.0 (t, JP-C ) 13.7, Ru-CO), 155.6 (t, JP-C ) 9.3,
Cipso Ph), 140.5, 135.8, 126.0, 124.5, 119.7 (all s, Ph), 23.4 (vt, N
) 15.5, PCH), 19.1, 18.7 (both s, PCH(CH3)2). MS (FAB+): m/z
562 (M+), 527 (M+ - Cl).
(30) Orpen, A. G.; Brammer, L.; Allen, F. H.; Kennard, O.; Whatson,
D. G.; Taylor, R. J. Chem. Soc., Dalton Trans. 1989, S1.
(31) See for example: (a) Foot, R. J.; Heaton, B. T. J. Chem. Soc., Dalton
Trans. 1979, 295. (b) Newkome, G. R.; Theriot, K. J.; Cheskin, B. K.;
Evans, D. W.; Baker, G. R. Organometallics 1990, 9, 1375. (c) Jia, G.;
Meek, D. W.; Gallucci, J. C. Organometallics 1990, 9, 2549. (d) Coalter,
J. N., III; Streib, W. E.; Caulton, K. G. Inorg. Chem. 2000, 39, 3749. (e)
Wong-Foy, A. G.; Henling, L. M.; Day, M.; Labinger, J. A.; Bercaw, J. E.
J. Mol. Catal. A: Chem. 2002, 189, 3.
Preparation of OsPhCl(CO)(PiPr3)2 (4). This complex was
prepared as described for 3 starting from 200 mg (0.35 mmol) of
2 and HgPh2 (185 mg, 0.52 mmol). Yield (garnet solid): 163 mg
(72%). Anal. Calcd for C25H47ClP2Os: C, 46.10; H, 2.27. Found:
1
C, 46.24; H, 7.39. IR (Nujol, cm-1): ν(CO) 1894 (s). H NMR
(32) Ozerov, O. V.; Pink, M.; Watson, L. A.; Caulton, K. G. J. Am.
Chem. Soc. 2004, 126, 2105.
(400 MHz, CD2Cl2, 223 K): δ 7.40 (d, JH-H ) 8.0, 1H, o-Ph),

3082 Organometallics, Vol. 25, No. 12, 2006
Buil et al.
6.91 (d, JH-H ) 8.0, 1H, o-Ph), 6.63-6.56 (m, 3H, Ph), 2.75 (m,
6H, PCH), 1.18 (dvt, N ) 12.9, JH-H ) 6.9, 18H, PCH(CH3)2),
1.02 (dvt, N ) 12.9, JH-H ) 6.6, 18H, PCH(CH3)2). 31P{1H} NMR
(121.42 MHz, CD2Cl2, 293 K): δ 20.4 (s). 13C{1H} NMR (100.56
MHz, CD2Cl2, 223 K): δ 183.0 (t, JP-C ) 8.7, Os-CO), 141.1,
135.4 (both s, Ph), 126.4 (t, JP-C ) 5.5, Cipso Ph), 125.8, 124.3,
119.8 (all s, Ph), 24.0 (vt, N ) 24, PCH), 19.4, 18.9 (both s,
PCH(CH3)2). MS (FAB+): m/z 652 (M+).
H, 6.90; N, 1.59. IR (Nujol, cm-1): ν (N-H) 3206 (m), ν(CtO)
1
1886 (s). H NMR (300 MHz, CD2Cl2, 193 K): δ 11.46 (br, 1H,
NH), 9.46 (d, 1H, JH-H ) 13.8, OsCHd), 7.63-6.36 (m, 15H,
Ph), 6.38 (d, 1H, JH-H ) 13.8, CHPh), 2.51 (br, 6H, PCH), 1.24
(br, 36H, PCH(CH3)2). 31P{1H} NMR (121.4 MHz, CD2Cl2, 193
K): δ -10.2 (s). 13C{1H} NMR (75.4 MHz, CD2Cl2, 193 K): δ
182.2 (br, CO), 174.7 (s, NdC), 143.1 (br, OsCd), 141.6, 139.0,
and 135.5 (all s, Cipso Ph), 135.2 (s, dCH), 130.2, 129.9, 128.5,
127.9, 127.6, 127.3, 122.9, and 122.4 (all s, Ph), 24.9 (br m, PCH),
19.5 and 19.2 (both br s, PCHCH3).
Spectroscopic Characterization of RuPhCl(CO)(NHdCPh2)-
(PiPr3)2 (5). In a 5 mm NMR tube 3 (20 mg, 0.036 mmol) and
benzophenone imine (6 µL, 0.036 mmol) were dissolved in 0.4
mL of dichloromethane-d2, and the sample was cooled at -70 °C,
Preparation of Ru{C6H4C(Ph)dNH}Cl(CO)(PiPr3)2 (11). This
complex can be prepared either starting from 3 (100 mg, 0.18 mmol)
and benzophenone imine (30.2 µL, 0.18 mmol) or from 7 (291
mg, 0.495 mmol) and benzophenone imine (83.0 µL, 0.495 mmol)
in toluene (15 mL). In both cases, the mixtures were heated under
reflux conditions for 24 h. The resulting reddish-orange solutions
were filtered and then concentrated almost to dryness. The addition
of pentane caused the formation of a yellow solid. The solutions
were decanted, and the solid was washed with pentane (2 × 3 mL).
Yield: starting from 3, 98 mg (82%); starting from 7, 280 mg
(85%). Anal. Calcd for C32H52ClONP2Ru: C, 57.78; H, 7.88; N,
2.11. Found: C, 58.17; H, 8.20; N, 2.30. IR (Nujol, cm-1): ν(N-
1
changing the color of the solution from brick-red to orange. H,
13C{1H}, and 31P{1H} NMR spectra recorded at this temperature
showed a mixture of 3 and 5 in a ratio of 1:1.8. NMR data of
RuPhCl(CO)(NHdCPh2)(PiPr3)2 (5): 1H NMR (400 MHz, CD2Cl2,
203 K): δ 11.60 (br, 1H, NH), 7.66 (d, JH-H ) 7.2, 1H, o-Ph),
7.58-6.75 (m, 14H, Ph), 2.27 (br, 6H, PCH), 1.30 (br, 18H, PCH-
(CH3)2), 0.80 (br, 18H, PCH(CH3)2). 31P{1H} NMR (161.9 MHz,
CD2Cl2, 203 K): δ 19.5 (s). 13C{1H} NMR (100.56 MHz, CD2Cl2,
203 K plus apt): δ 206.2 (t, JP-C ) 13.0, Ru-CO), 177.2 (s, NdC),
158.7 (t, JP-C ) 10.0, Cipso Ph), 144.9, 142.1 (both s, Ru-Ph),
139.2 and 137.3 (both s, Cipso imine) 128.8, 128.0, 129.7, 127.7,
127.4, 126.6 (all s, Ph imine), 125.2, 123.6 (both s, Ru-Ph), 24.8
(br, PCH), 19.8, 20.4 (both s, PCH(CH3)2).
1
H) 3325 (m), ν(CtO) 1910 (s). H NMR (300 MHz, C6D6, 293
K): δ 9.56 (br, 1H, NH), 8.57 (d, JH-H ) 7.8, 1H, Ph), 7.43-7.11
(m, 6H, Ph), 6.92 (t, JH-H ) 7.8, 1H, Ph), 6.73 (t, JH-H ) 7.3, 1H,
Ph), 2.32 (m, 6H, PCH), 1.49 (dvt, N ) 14.1, JH-H ) 7.2, 18H,
PCHCH3), 0.78 (dvt, N ) 12.0, JH-H ) 6.9, 18H, PCHCH3).
31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ 36.1 (s). 13C{1H}
NMR (75.4 MHz, C6D6, 293 K): δ 211.7 (t, JC-P ) 14.4, CO),
191.9 (t, JC-P ) 8.3, Ru-C), 181.9 (t, JC-P ) 3.5, NdC), 145.0,
144.3, 144.2, 138.9, 138.7, 138.3, 132.5, 132.2, 130.6, 129.7, 129.2,
126.1, and 120.3 (all s, Ph and C6H4); 24.2 (vt, N ) 19.2, PCH);
20.8 and 18.9 (both s, PCHCH3). MS (FAB+): m/z 665 (M+).
Spectroscopic Characterization of OsPhCl(CO)(NHdCPh2)-
(PiPr3)2 (6). In a 5 mm NMR tube 4 (20 mg, 0.031 mmol) and
benzophenone imine (5.1 µL, 0.036 mmol) were dissolved in 0.4
mL of dichloromethane-d2, and the sample was cooled at -50 °C,
changing the color of the solution from garnet to dark orange. 1H,
13C{1H}, and 31P{1H} NMR spectra recorded at this temperature
showed the formation of the title compound. NMR data of OsPhCl-
(CO)(NHdCPh2)(PiPr3)2 (6): 1H NMR (300 MHz, CD2Cl2, 223
K): δ 11.84 (br, 1H, NH), 8.44 (d, JH-H ) 7.7, 1H, o-Ph, Os-
Ph), 7.80 (d, JH-H ) 7.7, 1H, o-Ph, Os-Ph), 7.73-6.64 (m, 13H,
Ph), 2.43 (br, 6H, PCH), 1.27-0.60 (m, 36H, PCH(CH3)2). 31P{1H}
NMR (121.4 MHz, CD2Cl2, 223 K): δ -12.0 (s). 13C{1H} NMR
(75.4 MHz, CD2Cl2, 223 K plus apt): δ 182.5 (t, JP-C ) 9.0, Os-
CO), 175.1 (s, NdC), 158.7 (t, JP-C ) 10.0, Cipso Ph), 145.3, 141.9
(both s, Cortho Os-Ph), 139.3 (s, Cipso imine), 136.1 (t, JP-C ) 7.9,
Preparation of Os{C6H4C(Ph)dNH}Cl(CO)(PiPr3)2 (12). This
complex was prepared as described for 11 starting either from 4
(100 mg, 0.153 mmol) and benzophenone imine (26 µL, 0.153
mmol) or from 8 (100 mg, 0.147 mmol) and benzophenone imine
(25 µL, 0.147 mmol). Yield (pink solid): starting from 4, 98 mg
(85%); starting from 8, 89 mg (80%). Anal. Calcd for C32H52-
ClONOsP2: C, 50.95; H, 6.95; N, 1.86. Found: C, 50.53; H, 7.07;
N, 1.62. IR (Nujol, cm-1): ν(N-H) 3327 (m), ν(CtO) 1893 (s).
1H NMR (300 MHz, C6D6, 293 K): δ 9.40 (br, 1H, NH), 8.61-
C
ipso, Os-Ph), 130.5, 128.7, 128.3, 128.2, 127.9, 127.7 (all s, Ph),
125.6, 124.5, 119.6 (s, Os-Ph), 25.2 (br, PCH), 20.5, 20.3 (both
s, PCH(CH3)2).
6.69 (m, 9H, Ph), 2.41 (m, 6H, PCH), 1.45 (dvt, N ) 13.9, JH-H
)
Preparation of Ru{(E)-CHdCHPh}Cl(CO)(NHdCPh2)(PiPr3)2
(9). A deep red solution of 7 (30 mg, 0.051 mmol), in 5 mL of
CH2Cl2 at -80 °C, was treated with benzophenone imine (8.6 µL,
0.051 mmol) and was kept for 0.5 h at this temperature. The solvent
of the resulting solution was removed under reduced pressure, until
the formation of orange crystals. The remaining solution was
decanted, and the crystals were dried in a vacuum. Yield: 23 mg
(59%). Anal. Calcd for C40H60NClORuP2: C, 62.44; H, 7.86; N,
1.82. Found: C, 62.41; H, 7.72; N, 1.78. IR (Nujol, cm-1): ν(N-
H) 3229 (m), ν(CtO) 1904 (s). 1H NMR (300 MHz, CD2Cl2, 193
K): δ 11.26 (br, 1H, NH), 9.01 (d, 1H, JH-H ) 16.5, RuCHd),
7.64-6.86 (m, 15H, Ph), 6.36 (d, 1H, JH-H ) 16.5, CHPh), 2.42
(m, 6H, PCH), 1.01 (br, 36H, PCH(CH3)2). 31P{1H} NMR (121.4
MHz, CD2Cl2, 193 K): δ 21.1 (s). 13C{1H} NMR (75.4 MHz,
CD2Cl2, 193 K): δ 206.4 (t, JC-P ) 12.5, CO), 178.2 (s, NdC);
160.5 (s, RuCd); 140.7, 139.1, and 136.4 (all s, Cipso Ph); 136.8
(s, dCH); 131.3, 130.9, 130.7, 129.2, 128.6, 128.5, 128.1, 127.3,
123.7, and 123.4 (all s, Ph), 24.9 (br m, PCH), 20.3 and 20.1 (both
br s, PCHCH3).
7.1, 18H, PCHCH3), 0.81 (dvt, N ) 12.1, JH-H ) 6.7, 18H,
PCHCH3). 31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ 3.0 (s).
13C{1H} NMR (75.4 MHz, C6D6, 293 K): δ 193.8 (t, JC-P ) 9.1,
Os-C), 183.4 (t, JC-P ) 13.1, CO), 174.5 (s, NdC); 143.1, 138.2,
132.2, 130.3, 130.2, 129.2, 127.1, 126.8, 118.8 (all s, Ph and C6H4),
24.0 (vt, N ) 23.5, PCH); 20.6 and 18.8 (both s, PCHCH3). MS
(FAB+): m/z 755 (M+ + H).
Preparation of Ru(NC5H4-o-CHdCH)Cl(CO)(PiPr3)2 (13).
This complex can be prepared either starting from 3 (100 mg, 0.18
mmol) and 2-vinylpyridine (29 µL, 0.27 mmol) or from 7 (100
mg, 0.150 mmol) and 2-vinylpyridine (24 µL, 0.23 mmol) in toluene
(15 mL). In both cases, the mixtures were heated under reflux
conditions for 24 h. The resulting orange solution was filtered
through Celite and concentrated to dryness, getting an orange
residue. The addition of pentane (25 mL) led to an orange solution,
which was filtered and concentrated to ca. 5 mL. Cooling of this
solution overnight afforded yellow crystals. The pentane was
decanted and the crystals were washed with pentane. Yield: starting
from 3, 77 mg (73%); starting from 7, 76 mg (75%). Anal. Calcd
for C26H48ClNOP2Ru: C, 53.00; H, 8.21; N, 2.38. Found: C, 53.02;
H, 8.16; N, 2.15. IR (Nujol, cm-1): ν(CtO) 1923 (s), ν(CdC)
Preparation of Os{(E)-CHdCHPh}Cl(CO)(NHdCPh2)(PiPr3)2
(10). This complex was prepared as described for 9 starting from
30 mg (0.044 mmol) of 9 and benzophenone imine (7.4 µL, 0.044
mmol). Yield (orange crystals): 23 mg (61%). Anal. Calcd for
C40H60NClOOsP2: C, 55.96; H, 7.04; N, 1.63. Found: C, 55.72;
1
1600 (m). H NMR (300 MHz, C6D6, 293 K): δ 9.90 (ddd, JH-H
) 6.0, JH-H ) 1.5, JH-H ) 0.6, 1H, py), 9.81 (d, JH-H ) 8.0, 1H,

Displacement of Phenyl and Styryl Ligands
Organometallics, Vol. 25, No. 12, 2006 3083
Table 4. Crystal Data and Data Collection and Refinement for 9, 12, and 13
12
9
13
Crystal Data
formula
molecular wt
C40H60ClNOP2Ru
769.35
C32H52ClNOOsP2
754.34
C26H48ClNOP2Ru‚1/2C16H14‚1/4C5H12
710.29
color and habit
size, mm
symmetry, space group
orange, irregular block
0.14,0.10,0.06
monoclinic, P2(1)/c
11.2101(16)
11.3142(16)
30.803(4)
93.101(3)
3901.2(10)
4
red, irregular block
0.30,0.18,0.12
monoclinic, P2(1)/n
9.9565(19)
18.275(3)
17.730(3)
96.908(3)
3202.7(10)
4
1.564
yellow, prism
0.46,0.10,0.10
monoclinic, P2(1)
19.639(4)
9.7366(17)
20.438(4)
110.208(3)
3667.6(11)
4
a, Å
b, Å
c, Å
â, deg
V, Å3
Z
D
calc, g cm-3
1.310
1.286
Data Collection and Refinement
Bruker Smart APEX
diffractometer
λ(Mo KR), Å
monochromator
scan type
0.71073
graphite oriented
ω scans
µ, mm-1
0.583
3, 57
100.0(2)
46 533
4.190
0.614
3, 57
100.0(2)
45 835
17 649 (Rint ) 0.0541)
663/12
0.36(4)
0.0579
2θ, range, deg
temp, K
3, 57
100.0(2)
37 259
no. of data collected
no. of unique data
no. of params/restraints
Flack parameter
R1a [F2 > 2σ(F2)]
wR2b [all data]
Sc [all data]
9371 (Rint ) 0.0612)
7680 (Rint ) 0.0290)
358/0
436/2
0.0369
0.0710
0.898
0.0188
0.0399
0.991
0.1368
0.995
2
2
2
c
2
2
a R1(F) ) ∑||Fo| - |Fc||/∑|Fo|. b wR2(F2) ) {∑[w(Fo - Fc )2]/∑[w(Fo )2]}1/2. Goof ) S ) {∑[Fo - Fc )2]/(n - p)}1/2, where n is the number of
reflections and p is the number of refined parameters.
Ru-CH), 6.97 (ddd, JH-H ) 7.6, JH-H ) 7.2, JH-H ) 1.5, 1H, py),
6.78 (dt, JH-H ) 8.1, JP-H ) 1.3, 1H, Ru-CHdCH), 6.76 (dd,
ω. Data were corrected for absorption by using a multiscan method
applied with the SADABS program.33 The structures of all
compounds were solved by the Patterson method. Refinement, by
full-matrix least squares on F2 with SHELXL97,34 was similar for
all complexes, including isotropic and subsequently anisotropic
displacement parameters. For 13 the asymmetric unit shows two
independent, but chemically equivalent, molecules, a molecule of
1,4-diphenylbutadiene, and a half molecule of pentane in the unit
cell. The 1,4-diphenylbutadiene and the pentane molecule were
refined as isotropic with geometrical restraints. The PLATON
program35 suggests that the structure of complex 13 has an 85%
probability of being P2(1)/c. However, all our attempts to solve it
within this space group have been unsuccessful. The hydrogen
atoms were observed or calculated and refined freely or using a
restricted riding model. The hydrogen atoms of the imine groups
of complexes 9 and 12 were observed in the difference Fourier
maps and refined as free isotropic atoms. All the highest electronic
residuals were observed in close proximity of the metal centers
and make no chemical sense. Crystal data and details of the data
collection and refinement are given in Table 4.
JH-H ) 7.2, JH-H ) 0.6, 1H, py), 6.40 (ddd, JH-H ) 7.2, JH-H
6.0, JH-H ) 1.5, 1H, py), 2.22 (m, 6H, PCH), 1.23 (dvt, JH-H
)
)
7.2, N ) 13.5, 18H, PCH(CH3)2), 1.01 (dvt, JH-H ) 6.9, N ) 12.0,
18H, PCH(CH3)2). 31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ
32.3 (s). 13C{1H} NMR (75.4 MHz, C6D6, 293 K): δ 209.0 (t,
JC-P ) 15.5, CO), 200.4 (t, JC-P ) 9.1, Ru-CH), 166.5 (s, Nd
C-CHdCHRu), 152.8 (s, py), 135.8 (s, py), 128.7 (s, CHdCH),
119.2, 115.4 (both s, py), 24.8 (vt, N ) 18, PCH), 20.5 and 19.7
(both s, PCH(CH3)2). MS (FAB+): m/z 589 (M+), 554 (M+ - Cl).
Preparation of Os(NC5H4-o-CHdCH)Cl(CO)(PiPr3)2 (14).
This complex was prepared as described for 13 starting either from
4 (100 mg, 0.153 mmol) and 2-vinylpyridine (25 µL, 0.23 mmol)
or from 8 (100 mg, 0.147 mmol) and 2-vinylpyridine (24 µL, 0.22
mmol). Yield (orange solid): starting from 4, 75 mg (72%); starting
from 8, 70 mg (70%). Anal. Calcd for C26H48ClNOOsP2: C, 46.04;
H, 7.16; N, 2.06. Found: C, 46.15; H, 6.95; N, 1.94. IR (Nujol,
cm-1): ν(CtO) 1910 (s), ν(CdC) 1603 (m). 1H NMR (300 MHz,
C6D6, 293 K): δ 10.63 (d, JH-H ) 8.2, 1H, Os-CH), 9.83 (br d,
JH-H ) 5.1, 1H, py), 7.01 (d, JH-H ) 8.2, 1H, Os-CHdCH), 6.89
(ddd, JH-H ) 7.5, JH-H ) 0.9, 1H, py), 6.78 (ddd, JH-H ) 7.5,
Acknowledgment. Financial support from the MCYT of
Spain (Project CTQ2005-00656) is acknowledged. M.L.B.
thanks the Spanish MCYT/Universidad de Zaragoza for funding
through the “Ramo´n y Cajal” program.
JH-H ) 1.2, JH-H ) 1.2, 1H, py), 6.34 (ddd, JH-H ) 7.5, JH-H
5.1, JH-H ) 1.2, 1H, py), 2.33 (m, 6H, PCH), 1.21 (dvt, JH-H
)
)
7.2, N ) 13.5, 18H, PCH(CH3)2), 1.02 (dvt, JH-H ) 6.9, N ) 12.0,
18H, PCH(CH3)2). 31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ
0.8 (s). 13C{1H} NMR (75.4 MHz, C6D6, 293 K): δ 190.9 (t, JC-P
) 10.8, CO), 184.8 (t, JC-P ) 5.8, Os-CH), 169.1 (s, NdC-
CHdCHOs), 152.1 (s, py), 135.9 (s, py), 126.2 (s, CHdCH), 118.7,
114.4 (both s, py), 24.9 (vt, N ) 24.0, PCH), 20.4 and 19.5 (both
s, PCH(CH3)2). MS (FAB+): m/z 679 (M+), 644 (M+ - Cl).
Structural Analysis of Complexes 9, 12, and 13. X-ray data
were collected for all complexes on a Bruker Smart APEX CCD
diffractometer equipped with a normal focus, 2.4 kW sealed tube
source (Mo radiation, λ ) 0.71073 Å) operating at 50 kV and 30
mA. Data were collected over the complete sphere by a combination
of four sets. Each frame exposure time was 10 s covering 0.3° in
Supporting Information Available: Tables of positional and
displacement parameters, crystallographic data, and bond lengths
and angles of complexes 3, 12, and 13. This material is available
free of charge via the Internet at http://pubs.acs.org.
OM060222R
(33) Blessing, R. H. Acta Crystallogr. A 1995, 51, 33-38. SADABS,
Area-detector absorption correction; Bruker-AXS: Madison, WI, 1996.
(34) SHELXTL Package v. 6.10; Bruker-AXS: Madison, WI, 2000.
Sheldrick, G. M. SHELXS-86 and SHELXL-97; University of Go¨ttingen:
Go¨ttingen, Germany, 1997.
(35) Spek, A. L. PLATON, A Multipurpose Crystallographic Tool;
Utrecht University: Utrecht, The Netherlands, 2005.