Ene-type reactions between an α-alkenylphosphine and terminal alkynes promoted by osmmm-cyclopentadienyl fragments

Article abstract of DOI:10.1021/om0489857

Complex Os(η⁵-C₅H₅) Cl{[η²-CH₂=C(CH₃)]PⁱPr ₂} (1) reacts with phenylacetylene to give the dienylphosphine derivative Os(η⁵-C₅H₅)Cl{[η2

Full text of DOI:10.1021/om0489857

2030
Organometallics 2005, 24, 2030-2038
Articles
Ene-Type Reactions between an r-Alkenylphosphine and
Terminal Alkynes Promoted by
Osmium-Cyclopentadienyl Fragments
Miguel Baya, Mar´ıa L. Buil, Miguel A. Esteruelas,* and Enrique On˜ate
Departamento de Quı´mica Inorga´nica, Instituto de Ciencia de Materiales de Arago´n,
Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
Received December 22, 2004
Complex Os(η5-C5H5)Cl{[η2-CH2dC(CH3)]PiPr2} (1) reacts with phenylacetylene to give
the dienylphosphine derivative Os(η5-C5H5)Cl{[η2-(E)-PhCHdCHCH2C(dCH2)]PiPr2} (2). The
reaction of 1 with PhCtCD leads to the monodeuterated compound Os(η5-C5H5)Cl{[η2-(E)-
PhCHdCDCH2C(dCH2)]PiPr2} (2-d1). The position of the deuterium atom in 2-d1 is consistent
with the participation of π-alkyne intermediates in the formation of 2 and 2-d1. In agreement
with this, complex 1 reacts with 1,1-diphenyl-2-propyn-1-ol to give initially Os(η5-C5H5)Cl-
{η2-HCtCC(OH)Ph2}{PiPr2[C(CH3)dCH2]} (3), which in toluene under reflux evolves into
Os(η5-C5H5)Cl{[η2-(E)-{Ph2(OH)C}CHdCHCH2C(dCH2)]PiPr2} (4). Treatment of 1 with
lithium phenylacetylide affords the alkynyl derivative Os(η5-C5H5)(CtCPh){[η2-CH2dC(CH3)]Pi-
Pr2} (5). Complex 5 also reacts with 1,1-diphenyl-2-propyn-1-ol. The reaction initially gives
Os(η5-C5H5)(CtCPh){η2-HCtCC(OH)Ph2}{PiPr2[C(CH3)dCH2]} (6), which subsequently af-
fords Os(η5-C5H5)(CtCPh){[η2-(E)-{Ph2(OH)C}CHdCHCH2C(dCH2)]PiPr2} (7). Triethyl-
amine inhibits the coupling between the isopropenyl group of 1 and phenylacetylene. In the
presence of this base, the addition of phenylacetylene to 1 leads to the vinylidene derivative
Os(η5-C5H5)Cl(dCdCHPh){PiPr2[C(CH3)dCH2]} (8). The X-ray structures of 2 and 8 are also
reported.
Introduction
2). As ligand, they are attracting increased attention
in the chemistry of the metals. R-Alkenylphosphines act
as monodentate groups,6 can bridge to two metal
The development of efficient and selective methods
to form carbon-carbon bonds is a target with high
priority.1 Increasing emphasis is placed upon atom
economy in order to utilize raw materials more ef-
fectively and to minimize waste production.2 An ex-
ample of an atom economical process is the ene-type
reaction between an alkene and an alkyne. A variety of
transition metal complexes have been reported to
catalyze the intramolecular coupling of alkene and
alkyne functional groups, to produce cyclic 1,4-dienes.3
Cationic ruthenium(II) derivatives have been shown to
be active catalysts also for the intermolecular version
of this reaction (eq 1).4 Although osmium catalysts for
C-C bond formation are known,5 in the presence of
osmium species, neither catalytic nor stoichiometric ene-
type reactions between alkene and alkyne groups have
been described.
(1) (a) Schmalz, H. G. Angew. Chem., Int. Ed. Engl. 1995, 34, 1833.
(b) Naota, T.; Takaya, H.; Murahashi, S.-I. Chem. Rev. 1998, 98, 2599.
(c) Esteruelas, M. A.; Lo´pez, A. M. In Recent Advances in Hydride
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N.; Seki, Y. J. Am. Chem. Soc. 1998, 120, 9104. (b) Auber, C.; Buisine,
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1463. (c) Trost, B. M.; Toste, F. D.; Shen, H. J. Am. Chem. Soc. 2000,
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Treptow, B. J. Am. Chem. Soc. 1995, 117, 615. (d) Trost, B. M.; Mu¨ler,
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R-Alkenylphosphines are phosphorus-functionalized
olefins, which should afford phosphorus-functionalized
dienes by means of ene-type reactions with alkynes (eq
* To whom correspondence should be addressed. E-mail: maester@
unizar.es.
10.1021/om0489857 CCC: $30.25 © 2005 American Chemical Society
Publication on Web 03/18/2005

Ene Reactions Promoted by Os Fragments
Organometallics, Vol. 24, No. 9, 2005 2031
centers,7 and can act as chelating ligands.8 Further-
more, the reversible coordination-decoordination of the
olefinic moiety gives them hemilabile properties. As a
consequence, under appropriate conditions, they can be
used to stabilize highly reactive intermediates.9 Al-
though interest in the preparation of novel functional-
ized phosphines by their connection with homogeneous
catalysis is known,10 surprisingly, ene-type reactions of
the R-alkenylphosphines have not explored.
tinuation of our work in this program, we now report
the transformation of the isopropenyl substituent of the
phosphine into dienyl groups, by means of ene-type
reactions with alkynes.
Results and Discussion
1. Coupling between Isopropenyldi(isopropyl)-
phosphine and Phenylacetylene Promoted by the
Fragment Os(η5-C5H5)Cl. One of the great utilities of
the transition metals is their ability to direct reactivity
of organic molecules toward the rarely activated centers.
The osmium fragment Os(η5-C5H5)Cl deactivates the
phosphorus Lewis base capacity of isopropenyldi(iso-
propyl)phosphine by coordination, while it activates the
isopropenyl carbon-carbon double bond to the coupling
with phenylacetylene. Treatment at room temperature
of toluene solutions of the complex Os(η5-C5H5)Cl{[η2-
CH2dC(CH3)]PiPr2} (1) with 3.6 equiv of the phenyl-
acetylene leads after 7 h to the dienyl phosphine
As part of our work on the chemistry of the Os-
cyplopentadienyl unit,11 we have recently initiated a
research program dedicated to the functionalization of
trialkylphosphines, in particular triisopropylphosphine.
Because, in contrast to alkanes, the reactions involving
alkenes are promising processes regarding synthetic
applications, the dehydrogenation of an isopropyl group
of the phosphine was performed12 as the first step of
the program. In subsequent stages, we have converted
the resulting isopropyldi(isopropyl)phosphine into R-al-
lylphosphines by reaction with diazoalkanes via [2+2]
cycloaddition reactions13 and iminophosphines by inser-
tion of the carbon-nitrogen triple bond of benzonitriles
into one of the C(sp2)-H bonds of the isopropenyl group
of the isopropenyldi(isopropyl)phosphine.14 As a con-
derivative
Os(η5-C5H5)Cl{[η2-(E)-PhCHdCHCH2C-
(dCH2)]PiPr2} (2), which was isolated, according to eq
3, as an orange solid in 87% yield.
(5) (a) Esteruelas, M. A.; Herrero, J.; Lo´pez, A. M.; Oliva´n, M.
Organometallics 2001, 20, 3202. (b) Cobo, N.; Esteruelas, M. A.;
Gonza´lez, F.; Herrero, J.; Lo´pez, A. M.; Lucio, P.; Oliva´n, M. J. Catal.
2004, 223, 319.
Figure 1 shows a view of the structure of this
derivative. Selected bond distances and angles are listed
in Table 1. The structure proves the formation of the
dienyl phosphine, which shows a gem disposition for the
substituents of the C(1)-C(11) olefinic bond and E-
stereochemistry at the C(3)-C(4) double bond. The
phosphine acts a bidentate ligand through the phos-
phorus atom and the olefinic C(3)-C(4) bond. Thus, the
geometry around the osmium center can be described
as a distorted octahedron, with the cyclopentadienyl
ligand occupying the three sites of a face, whereas the
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2032 Organometallics, Vol. 24, No. 9, 2005
Baya et al.
while the C(sp3)H2 protons display multiplets at 2.60
and 2.30 ppm. The olefinic resonances at C(3)H and
C(4)H are observed at 4.72 and 4.66 ppm, respectively.
The first of them appears as a multiplet, whereas the
second one is a doublet with a H-H coupling constant
of 9.9 Hz. In the 13C{1H} NMR spectrum, the olefinic
carbon atoms C(1) and C(11) display a doublet at 151.9
ppm (C(1)), with a C-P coupling constant of 38.2 Hz,
and a singlet at 117.9 ppm (C(11)). The resonance
corresponding to the sp3-C(2) atom is observed at 39.3
ppm, as a doublet with a C-P coupling constant of 25.3
Hz. The resonances due to the coordinated C(3) and C(4)
atoms are observed at 39.9 and 53.8 ppm, respectively.
The first of them appears as a singlet, while the second
one is a doublet with a C-P coupling constant of 2.3
Hz. The 31P{1H} NMR spectrum shows a singlet at 42.5
ppm, shifted 45.4 ppm to lower field in comparison with
the resonance of 1.
The formation of 2 can be certainly rationalized as
an ene-type reaction between the isopropenyl substitu-
ent of the phosphine of 1 and the alkyne. It is note-
worthy the high regioselectivity of the process. Although
three stereoisomers are feasible, only that with the
smallest steric hindrance between the initial organic
moieties is formed.
It is generally believed that this type of reaction
proceeds via a metalacyclopentene intermediate,4h which
is generated by oxidative coupling between the olefin
and alkyne substrates. The E-configuration at the C(3)-
C(4) double bond of 2 and the disposition of the phenyl
group, away from the osmium atom, are consistent with
this proposal. In favor of the formation of an osmacy-
clopentene unit, by coupling of coordinated π-olefin and
π-alkyne ligands, we have also observed that 1 reacts
with PhCtCD to afford exclusively Os(η5-C5H5)Cl{[η2-
(E)-PhCHdCDCH2C(dCH2)]PiPr2} (2-d1), containing
1.0 deuterium atom at C(3) (eq 4).
Figure 1. Molecular diagram of complex Os(η5-C5H5)Cl-
{[η2-(E)-PhCHdCHCH2C(dCH2)]PiPr2} (2).
Table 1. Selected Bond Distances (Å) and Angles
(deg) for the Complex 2a
Os-P
2.2990(12)
2.4268(11)
2.203(4)
2.184(4)
1.296(6)
1.506(6)
1.421(6)
Os-C(18)
Os-C(19)
Os-C(20)
Os-C(21)
Os-C(22)
C(2)-C(3)
C(4)-C(5)
2.171(5)
2.236(4)
2.274(4)
2.256(4)
2.170(4)
1.529(6)
1.456(6)
Os-Cl
Os-C(3)
Os-C(4)
C(1)-C(11)
C(1)-C(2)
C(3)-C(4)
P-OsG
129.3
P-C(1)-C(2)
106.9(4)
124.5(5)
111.1(4)
119.7(4)
116(2)
P-Os-M
P-Os-Cl
G-Os-M
G-Os-Cl
M-Os-Cl
C(3)-Os-C(4)
89.3
C(11)-C(1)-C(2)
C(1)-C(2)-C(3)
C(2)-C(3)-C(4)
C(2)-C(3)-H(3)
C(5)-C(4)-H(4)
87.30(4)
125.3
117.6
98.4
37.78(15)
114(3)
a G is the centroid of the C(18)-C(22) Cp ligand. M is the
midpoint of the C(3)-C(4) double bond.
phosphorus atom, the midpoint of the olefinic C(3)-C(4)
bond (M), and the chloride ligand are situated on sites
of the opposite face. The angles P-Os-Cl, P-Os-M,
and M-Os-Cl are 87.30(4)°, 89.3°, and 98.4°, respec-
tively.
The osmium-styryl coordination exhibits Os-C dis-
tances of 2.203(4) Å (Os-C(3)) and 2.184(4) Å (Os-C(4)),
which agree well with those found in other osmium-
olefin complexes (between 2.13 and 2.28 Å).8d,9b,c,11n,12,15
Similarly, the olefinic bond distance C(3)-C(4)
(1.421(6) Å) is within the range reported for transition
metal olefin complexes (between 1.340 and 1.455 Å).16
In agreement with the presence of a C(1)-C(11) double
bond, the separation between these atoms is 1.296(6)
Å.
The presence of the deuterium atom at C(3) of 2-d1
1
2
is demostrated by the H and H NMR spectra of this
1
compound. The H NMR spectrum shows the absence
of the resonance at 4.72 ppm, while the 2H NMR
spectrum contains a singlet at 4.71 ppm.
Scheme 1 summarizes the elemental steps, which
could lead to 2. The hemilabile properties of the isopro-
penyldi(isopropyl)phosphine ligand should involve not
only the isopropenyl group but also the phosphorus
atom. Thus, the decoordination of the latter in 1 should
afford an unsaturated intermediate, which by coordina-
tion of the alkyne could give the key species, π-olefin-
π-alkyne. The oxidative coupling of these unsaturated
ligands should afford the osmacyclopentene intermedi-
ate, which could evolve by a hydrogen â-elimination
reaction on the methyl substituent at the CR(sp3) atom
of the metalacycle. The â-elimination reaction should
lead to a hydride-alkenyl intermediate. Thus, the sub-
sequent reductive elimination of olefin followed by the
coordination of the phosphorus atom to the metallic
center could finally generate 2.
1
The H, 13C{1H}, and 31P{1H} NMR spectra of 2 are
consistent with the structure shown in Figure 1. In the
1H NMR the C(sp2)H2 protons give rise to doublets at
5.28 (trans to P) and 4.93 (cis to P) ppm, with H-P
coupling constants of 27.0 and 11.7 Hz, respectively,
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C.; Oliva´n, M.; On˜ate, E. Organometallics 2000, 19, 3260. (e) Barrio,
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D. G. J. Chem. Inf. Comput. Sci. 1991, 31, 187.

Ene Reactions Promoted by Os Fragments
Organometallics, Vol. 24, No. 9, 2005 2033
Scheme 1
by the IR spectrum of this compound, which shows a
1
ν(O-H) band at 3361 cm-1. In the H NMR spectrum
the resonance corresponding to the OH proton appears
at 6.59 ppm as a singlet. The C(sp2)H2 protons of the
phosphine display double doublets, at 5.71 (trans to P)
and 4.89 (cis to P) ppm, with a H-H coupling constant
of 1.2 Hz and H-P coupling constants of 24.9 and 10.8
Hz, respectively. The C(sp3)H2 protons give rise to
double doublets at 3.20 and 2.19 ppm, the first of them
with a H-H coupling constant of 16.2 Hz and a H-P
coupling constant of 31.2 Hz, and the second one with
H-H coupling constants of 16.2 and 4.8 Hz. The
resonances due to a coordinated olefinic group are
observed at 4.80 and 4.04 ppm. The first of them
appears as a doublet with a H-H coupling constant of
9.3 Hz, while the second one is a double doublet with
H-H coupling constants of 9.3 and 4.8 Hz. In the 13C-
{1H} NMR spectrum, the olefinic CdCP carbon atoms
display a doublet at 142.5 ppm, with a C-P coupling
constant of 33.3 Hz (CP), and a singlet at 122.1 ppm
(dCH2). The resonance corresponding to the C(sp3)H2
carbon atom is observed at 43.8 ppm, as a doublet with
a C-P coupling constant of 23.4 Hz. The resonances due
to the coordinated carbon atoms appear at 57.2 and 44.0
ppm as singlets. The 31P{1H} NMR spectrum shows a
singlet at 34.4 ppm.
3. Coupling between Isopropenyldi(isopropyl)-
phosphine and 1,1-Diphenyl-2-propyn-1-ol Pro-
moted by the Fragment Os(η5-C5H5)(CtCPh). The
replacement of the chloride ligand in the fragment Os-
(η5-C5H5)Cl by a phenylacetylide group does not appear
to have a significant influence in this type of reaction.
Thus, we have observed that the isopropenyldi(iso-
propyl)phosphine-1,1-diphenyl-2-propyn-1-ol coupling
shown in Scheme 2 is also promoted by the fragment
Os(η5-C5H5)(CtCPh) (Scheme 3).
2. Coupling between Isopropenyldi(isopropyl)-
phosphine and 1,1-Diphenyl-2-propyn-1-ol Pro-
moted by the Fragment Os(η5-C5H5)Cl. The ene-type
reaction shown in eq 3 can be extended to alkynols. In
contrast to the formation of 2 the process is a two-step
procedure (Scheme 2). The addition at room tempera-
ture of 1.5 equiv of 1,1-diphenyl-2-propyn-1-ol to diethyl
ether solutions of 1 leads to the π-alkynol derivative
Os(η5-C5H5)Cl{η2-HCtCC(OH)Ph2}{PiPr2[C(CH3)d
CH2]} (3), which was isolated as a pink solid in 92%
yield. The π-coordination of the alkynol is strongly
supported by the IR spectrum, in which the CtC
stretching frequency is found at 1808 cm-1, shifted 309
cm-1 to lower wavenumbers in comparison with the
CtC stretching frequency in the free alkyne (2117
1
cm-1).11d,17 In the H NMR spectrum, the most notice-
able resonances of the alkynol are a singlet at 6.84 ppm
corresponding to the O-H proton and a doublet at 4.40
ppm with a H-P coupling constant of 12.6 Hz due to
the C(sp)-H proton. The resonances corresponding to the
CH2 protons of the phosphine isopropenyl group are
observed at 5.20 (trans to P) and 4.95 (cis to P) ppm, as
doublets with H-P coupling constants of 30.0 and 12.9
Hz, respectively. These resonances are shifted 1.10
(trans to P) and 2.08 (cis to P) with regard to those found
in the spectrum of 1 (δ, 4.10 and 2.87).12 In the 13C{1H}
NMR spectrum, the resonances due to the propargyl
unit of the alkyne appear between 77 and 89 ppm as
singlets. The resonances corresponding to the C(sp2)
isopropenyl carbon atoms are observed at 139.6 and
126.2 ppm. The first of them due to the CP atom appears
as a doublet with a C-P coupling constant of 35.9 ppm,
while the second one is observed as a singlet. The 31P-
{1H} NMR spectrum contains a singlet at 15.9 ppm.
In toluene under reflux complex 3 evolves into
Os(η5-C5H5)Cl{[η2-(E)-{Ph2(OH)C}CHdCHCH2C(dCH2)]-
PiPr2} (4), which was isolated as a green solid in 74%
yield. The formation of 4 indicates that the ene-type
reactions between R-alkenylphosphines and alkynols
can afford dienylphosphines, which are functionalized
with an alcohol group. The process shows the same level
of regioselectivity as the formation of 2. This suggests
that the products of these reactions are formed under
thermodynamic control.
The alkynyl complex Os(η5-C5H5)(CtCPh){[η2-
CH2dC(CH3)]PiPr2} (5) was prepared by treatment at
room temperature of tetrahydrofuran solutions of 1 with
2.0 equiv of lithium phenylacetylide. It was isolated as
an orange solid in 65% yield and characterized by MS,
1
elemental analysis, IR, and H, 13C{1H}, and 31P{1H}
NMR spectroscopy. In agreement with the presence of
an alkynyl ligand in this compound, its IR spectrum in
Nujol shows a band at 2083 cm-1 corresponding to the
1
ν(CtC) vibration. The H NMR spectrum is consistent
with that of 1. The olefinic CH2 protons of the isopro-
penyl substituent of the phosphine give rise to double
doublets at 3.48 (trans to P) and 2.41 (cis to P) ppm,
with a H-H coupling constant of 2.1 Hz and H-P
coupling constants of 30.3 and 6.6 Hz, respectively. In
the 13C{1H} the C(sp) carbon atoms of the alkynyl ligand
display doublets at 111.5 (Câ) and 85.1 (CR) ppm with
C-P coupling constants of 3.8 and 20.3 Hz, respectively,
whereas the C(sp2) carbon atoms of the phosphine give
rise to a doublet at 31.2 ppm (CP), with a C-P coupling
constant of 18.4 Hz, and a singlet at 24.0 (CH2) ppm.
The 31P{1H} NMR spectrum shows a singlet at -1.85
ppm.
The addition at room temperature of 1.5 equiv of 1,1-
diphenyl-2-propyn-1-ol to diethyl ether solutions of 5
leads to the π-alkynol derivative Os(η5-C5H5)(CtCPh)-
{η2-HCtCC(OH)Ph2}{PiPr2[C(CH3)dCH2]} (6), which
was isolated as a pale yellow solid in 65% yield. In the
The presence of an alcohol function in the dienyl
substituent of the phosphine of 4 is strongly supported
(17) Esteruelas, M. A.; Lahoz, F. J.; Martin, M.; On˜ate, E.; Oro, L.
A. Organometallics 1997, 16, 4572.

2034 Organometallics, Vol. 24, No. 9, 2005
Baya et al.
Scheme 2
Scheme 3
with H-H coupling constants of 9.9 and 4.5 Hz. The
13C{1H} NMR spectrum of 7 agrees well with that of 4;
the olefinic CdCP group gives rise to a doublet at 144.1
ppm, with a C-P coupling constant of 36.9 Hz, and a
singlet at 121.7 ppm. The resonance corresponding to
the C(sp3)H2 carbon atom of the phosphine appears at
43.6 ppm, as a doublet with a C-P coupling constant
of 23.9 Hz, whereas the coordinated C(sp2) carbon atoms
of the chelate ligand display singlets at 51.2 and 37.6
ppm. The resonances due to the C(sp) carbon atoms of
the alkynyl ligand are observed at 117.5 (Câ) and 77.1
(CR) ppm. The first of them appears as a singlet, while
the second one is a doublet with a C-P coupling
constant of 16.8 Hz. The 31P{1H} NMR spectrum
contains a singlet at 38.3 ppm.
1H NMR spectrum, the most noticeable resonances of
the alkynol are a singlet at 4.25 ppm corresponding to
the O-H proton and a doublet at 4.04 ppm, with a H-P
coupling constant of 9.3 Hz due to the C(sp)-H proton.
The resonances corresponding to the CH2 group of the
phosphine are observed at 5.24 (trans to P) and 5.03
(cis to P), as doublets with H-P coupling constants of
30.3 and 12.6 Hz, respectively. In the 13C{1H} NMR
spectrum, the resonances due to the C(sp) carbon atoms
of the alkynyl ligand appear at 116.5 (Câ) and 78.3 (CR)
ppm, the first of them as a singlet and the second one
as a doublet with a C-P coupling constant of 21.6 Hz.
The resonances of the C(sp) carbon atoms of the
π-alkynol are observed at 125.3 (tCH) and 75.7 (tC)
ppm, as singlets, whereas the C(sp2) carbon atoms of
the phosphine give rise to a doublet at 143.2 (CP) ppm,
with a C-P coupling constant of 36.9 Hz, and a singlet
at 124.5 ppm. The 31P{1H} NMR spectrum shows a
singlet at 20.3 ppm.
4. Triethylamine Inhibits the Coupling. Complex
Os(η5-C5H5)Cl(PiPr3)2 reacts with terminal alkynes and
alkynols to afford π-alkyne and π-alkynol derivatives
related to 3 and 6. In contrast to the isopropenyldi-
(isopropyl)phosphine complexes, these triisopropylphos-
phine derivatives evolve into the corresponding vi-
nylidene and hydroxyvinylidene compounds.11b From a
mechanistic point of view, it has been proposed that the
transformation proceeds via 1,2-hydrogen shift on the
π-alkyne species or, alternatively, through hydride-
alkynyl intermediates.18 For the latter pathway, Puerta
and co-workers have proved that the vinylidene results
from the dissociation of the hydride as a proton and the
subsequent protonation at the Câ atom of the alkynyl
ligand of the metal-alkynyl species.18f In agreement with
Puerta’s results, it has been observed that the presence
of bases favors the alkyne-vinylidene isomerization.11j
Triethylamine inhibits the ene-type reaction between
isopropenyldi(isopropyl)phosphine and alkynes. In con-
trast to the reaction shown in eq 3, in the presence of
6.0 equiv of triethylamine, the treatment of toluene
solutions of 1 with 6.3 equiv of phenylacetylene leads
to the vinylidene complex Os(η5-C5H5)Cl(dCdCHPh)-
{PiPr2[C(CH3)dCH2]} (8), which was isolated as red
crystals in 73% yield (eq 5).
In a manner similar to 3, in toluene under reflux,
complex 6 evolves into the ene-reaction product
Os(η5-C5H5)(CtCPh){[η2-(E)-{Ph2(OH)C}CHd
CHCH2C(dCH2)]PiPr2} (7), which was isolated as a
white solid in 78% yield. The presence of an OH group
in the dienyl substituent of the phosphine is supported
by the IR spectrum of the compound, which shows a
1
ν(OH) band at 3368 cm-1. In the H NMR spectrum in
benzene-d6, the OH resonance appears masked by the
phenyl signals. However in dichlorometane-d2, it is
observed at 6.77 ppm as a singlet. In benzene-d6, the
C(sp2)H2 group of the phosphine display two double
doublets at 5.53 (trans to P) and 4.62 (cis to P) ppm with
a H-H coupling constant of 2.4 Hz and H-P coupling
constants of 24.3 and 10.8 Hz, respectively. The C(sp3)-
H2 protons give rise to double doublets at 2.94 and 2.11
ppm, the first of them with a H-H coupling constant
of 15.6 and a H-P coupling constant of 30.5, and the
second one with H-H coupling constants of 15.6 and
4.5 Hz. The resonances due to the coordinated olefinic
group are observed at 3.60 and 3.43 ppm. The first of
them is a doublet with a H-H coupling constant of 9.9
Hz, while the second one appears as a double doublet
Triethylamine accelerates the alkyne-vinylidene trans-
formation. So, the formation of 8 suggests that on Os-
(η5-C5H5)X fragments the oxidative coupling between
the isopropenyl substituent of an isopropenylphosphine
and the carbon-carbon triple bond of a terminal alkyne
or alkynol (Scheme 1) is faster than the alkyne-vin-
ylidene transformation.
Figure 2 shows a view of the structure of 8. Selected
bond distances and angles are listed in Table 2. The
geometry around the osmium center is close to octahe-

Ene Reactions Promoted by Os Fragments
Organometallics, Vol. 24, No. 9, 2005 2035
compound. In the 1H NMR spectrum the resonance due
to the dCH proton of the vinylidene appears at 2.82
ppm, as a singlet, whereas the CH2 resonances of the
isopropenyl substituent of the phosphine are observed
at 5.26 (trans to P) and 5.06 (cis to P) ppm as doublets
with H-P coupling constants of 31.5 and 13.5 Hz,
respectively. In the 13C{1H} NMR spectrum, the most
noticeable resonances of the vinylidene ligand are a
doublet at 292.6 ppm, with a C-P coupling constant of
14.3 Hz due to the CR carbon atom, and a singlet at
117.0 ppm corresponding to the Câ carbon atom. The
C(sp2) atoms of the isopropenyl group of the phosphine
display doublets at 142.2 (CP) and 125.3 (CH2) ppm,
with C-P coupling constants of 39.2 and 4.6 Hz,
respectively. The 31P{1H} NMR spectrum shows a
singlet at 19.5 ppm.
We note that the indenyl-â-alkenylphosphine-ruthe-
nium(II) cation [Ru(η5-C5H5){[η2-CH2dCHCH2]PPh2}-
(PPh3)]+ reacts with terminal alkynes to afford vin-
ylidene intermediates, which evolve into bicyclic alky-
lidene compounds by an intramolecular [2+2] cyclo-
addition process between the olefinic substituent of the
phosphine and the CR-Câ double bond of the vinylidene
ligands.20 In contrast to this ruthenium system, complex
8 is stable and the coupling between the isopropenyl
substituent of the phosphine and the vinylidene is not
observed, even in toluene at 80 °C.
Figure 2. Molecular diagram of complex Os(η5-C5H5)-
Cl(dCdCHPh){PiPr2[C(CH3)dCH2]} (8).
Table 2. Selected Bond Distances (Å) and Angles
(deg) for the Complex 8a
Os-P
2.3028(11)
2.3906(10)
1.817(5)
1.328(6)
1.460(6)
1.334(7)
Os-C(18)
Os-C(19)
Os-C(20)
Os-C(21)
Os-C(22)
2.195(4)
2.289(4)
2.322(4)
2.302(4)
2.188(4)
Os-Cl
Os-C(1)
C(1)-C(2)
C(2)-C(3)
C(12)-C(14)
P-Os-G
129.9
G-Os-C(1)
120.7
P-Os-Cl
P-Os-C(1)
G-Os-Cl
88.51(4)
89.05(13)
117.8
Cl-Os-C(1)
103.35(13)
170.4(4)
125.9(4)
Os-C(1)-C(2)
C(1)-C(2)-C(3)
Concluding Remarks
a G is the centroid of the C(18)-C(22) Cp ligand.
This paper reveals that the osmium-cyclopentadienyl
Os(η5-C5H5)X fragments (X ) Cl, CtCPh) promote ene-
type reactions between the carbon-carbon double bond
of an R-alkenylphosphine and the carbon-carbon triple
bond of alkyne and alkynol substrates. The carbon-
carbon couplings afford dienylphosphine ligands, in-
cluding those functionalized with an alcohol group.
Thus, we show that the reactions of complexes Os(η5-
C5H5)X{[η2-CH2dC(CH3)]PiPr2} (X ) Cl, CtCPh) with
phenylacetylene and 1,1-diphenyl-2-propyn-1-ol lead to
the dienylphosphine derivatives Os(η5-C5H5)Cl{[η2-(E)-
PhCHdCHCH2C(dCH2)]PiPr2} and Os(η5-C5H5)X{[η2-
(E)-{Ph2(OH)C}CHdCHCH2C(dCH2)]PiPr2} (X ) Cl,
CtCPh).
On the basis of the high regioselectivity of the
reactions and the results of an isotope labeling experi-
ment, the formation of the dienylphosphine ligands can
be rationalized as olefin-alkyne oxidative couplings on
π-alkyne species, which lead to metalacyclopentane
intermediates. In agreement with this proposal, the
π-alkynol derivatives Os(η5-C5H5)X{η2-HCtCC(OH)-
Ph2}{PiPr2[C(CH3)dCH2]} (X ) Cl, CtCPh) have been
isolated and characterized.
dral, with the cyclopentadienyl ligand occupying a face.
The C(1)-Os-P, C(1)-Os-Cl, and P-Os-Cl angles are
89.05(13)°, 103.35(13)°, and 88.51(4)°, respectively.
The vinylidene ligand is bound to the metal in a
nearly linear fashion, with an Os-C(1)-C(2) angle of
170.4(4)°. The Os-C(1) (1.817(5) Å) and C(1)-C(2)
(1.328(6) Å) bond lengths compare well with those found
in other osmium-vinylidene complexes19 and support the
vinylidene formulation.
The presence of a vinylidene ligand in 8 is strongly
1
supported by the H and 13C{1H} NMR spectra of this
(18) See for example: (a) Bruce, M. I.; Chem. Rev. 1991, 91, 197.
(b) Le Lagadec, R.; Roman, E.; Toupet, L.; Mu¨ller, U.; Dixneuf, P. H.
Organometallics 1994, 13, 5030. (c) Wakatsuki, Y.; Koga, N.; Yamazaki,
H.; Morokuma, K. J. Am. Chem. Soc. 1994, 116, 8105. (d) Esteruelas,
M. A.; Oro, L. A.; Valero, C. Organometallics 1995, 14, 3596. (e) de los
R´ıos, I.; Jime´nez-Tenorio, M.; Puerta, M. C.; Valerga, P. J. Chem. Soc.,
Chem. Commun. 1995, 1757. (f) de los R´ıos, I.; Jime´nez-Tenorio, M.;
Puerta, M. C.; Valerga, P. J. Am. Chem. Soc. 1997, 119, 6529. (g)
Wakatsuki, Y.; Koga, N.; Werner, H.; Morukuma, K. J. Am. Chem.
Soc. 1997, 119, 360. (h) Stegmann, R.; Frenking, G. Organometallics
1998, 17, 2089. (i) Cadierno, V.; Gamasa, M. P.; Gimeno, J.; Pe´rez-
Carren˜o, E.; Garc´ıa-Granda, S. Organometallics 1999, 18, 2821. (j)
Puerta, M. C.; Valerga, P. Coord. Chem. Rev. 1999, 195, 977. (k)
Bustelo, E.; Jime´nez-Tenorio, M.; Puerta, M. C.; Valerga, P. Organo-
metallics 1999, 18, 950. (l) Bustelo, E.; Jime´nez-Tenorio, M.; Puerta,
M. C.; Valerga, P. Organometallics 1999, 18, 4563. (m) Aneetha, H.;
Jime´nez-Tenorio, M.; Puerta, M. C.; Valerga, P.; Mereiter, K. Orga-
nometallics 2003, 22, 2001.
(19) See for example: (a) Huang, D. J.; Oliva´n, M.; Huffman, J. C.;
Eisenstein, O.; Caulton, K. G. Organometallics 1998, 17, 4700. (b)
Esteruelas, M. A.; Oliva´n, M.; On˜ate, E.; Ruiz, N.; Tajada, M. A.
Organometallics 1999, 18, 2953. (c) Bohanna, C.; Buil, M. L.; Esteru-
elas, M. A.; On˜ate, E.; Valero, C. Organometallics 1999, 18, 5176. (d)
Castarlenas, R.; Esteruelas, M. A.; On˜ate, E. Organometallics 2000,
19, 5454. (e) Castarlenas, R.; Esteruelas, M. A.; Gutie´rrez-Puebla, E.;
On˜ate, E. Organometallics 2001, 20, 1545. (f) Barrio, P.; Esteruelas,
M. A.; On˜ate, E. Organometallics 2002, 21, 2491. (g) Barrio, P.;
Esteruelas, M. A.; On˜ate, E. Organometallics 2003, 22, 2472.
The oxidative couplings are faster than the isomer-
ization of the alkynes into vinylidenes. Triethylamine
accelerates the latter process. As a consequence, in the
presence of this amine, the ene-type reactions are
inhibited and the formation of vinylidene species takes
place.
(20) (a) Alvarez, P.; Lastra, E.; Gimeno, J.; Bassetti, M.; Falvello,
L. R. J. Am. Chem. Soc. 2003, 125, 2386. (b) Bran˜a, P.; Gimeno, J.;
Sordo, J. A. J. Org. Chem. 2004, 69, 2544. (c) Bassetti, M.; Alvarez,
P.; Gimeno, J.; Lastra, E. Organometallics 2004, 23, 5127.

2036 Organometallics, Vol. 24, No. 9, 2005
Baya et al.
diethyl ether was treated with HCtC-C(OH)Ph2 (127 mg,
0.61 mmol) for 30 min. The resulting solution was vacuum-
dried, and the residue was washed with pentane (3 × 4 mL).
A pink solid was obtained. Yield: 256 mg (92%). Anal. Calcd
for C29H36ClOOsP: C, 52.99; H, 5.52. Found: C, 53.33; H, 5.63.
In conclusion, we show a novel method to prepare
dienylphosphine derivatives, starting from R-alken-
ylphosphine complexes and alkynes.
Experimental Section
1
IR (Nujol, cm-1): ν(O-H) 3331 (f); ν(CtC) 1808 (s). H NMR
(300 MHz, C6D6, 293 K): δ 8.10-7.00 (10H, Ph); 6.84 (s, 1H,
OH); 5.20 (d, 1H, JH-P ) 30.0 Hz, PCdCHtrans to P); 4.95 (d, 1H,
JH-P ) 12.9 Hz, PCdCHcis to P); 4.77 (s, 5H, η5-C5H5); 4.40 (d,
1H, JH-P ) 12.6, HCt); 2.44 (m, 3H, PCH); 1.62 (d, 3H, JH-P
) 9.3, P-C(CH3)d); 0.92 (dd, 6H, JH-P ) 14.4, JH-H ) 7.2,
PCHCH3); 0.91 (dd, 6H, JH-P ) 14.4, JH-H ) 7.2, PCHCH3).
13C{1H} NMR (75.4 MHz, CD2Cl2, 243 K, plus APT): δ 148.2
(s, Cipso Ph); 139.6 (d, JC-P ) 35.9, PCd); 128.2, 127.3, and
127.0 (all s, Ph); 126.2 (s, dCH2); 88.8, 80.7 and 77.7 (all s,
HCtC-C(OH); 79.3 (s, η5-C5H5); 25.7 (d, JC-P ) 30.9, PCH);
23.2 (s, PC(CH3)); 19.6 and 19.2 (both s, PCHCH3). 31P{1H}
NMR (121.4 MHz, C6D6, 293 K): δ 15.9 (s). MS (LSIMS+): m/z
) 658 (M+); 639 (M+ - OH); 623 (M+ - Cl); 605 (M+ - OH -
Cl).
All reactions were carried out with rigorous exclusion of air
using Schlenk-tube techniques. Solvents were dried by the
usual procedures and distilled under argon prior to use. The
starting material Os(η5-C5H5)Cl{[η2-CH2dC(CH3)]PiPr2} (1)
was prepared by the published method.12
1H, 31P{1H}, and 13C{1H} NMR spectra were recorded on
either a Varian UNITY 300, a Varian Gemini 2000, a Bruker
AXR 300, or a Bruker Avance 300 MHz instrument. Chemical
shifts (expressed in parts per million) are referenced to
residual solvent peaks (1H, 13C{1H}) or external H3PO4 (31P-
{1H}). Coupling constants, J, are given in hertz. Infrared
spectra were run on a Perkin-Elmer 1730 spectrometer (Nujol
mulls on polyethylene sheets). C, H, and N analyses were
carried out in a Perkin-Elmer 2400 CHNS/O analyzer. Mass
spectra analyses were performed with a VG Austospec instru-
ment. In LSIMS+ mode, ions were produced with the standard
Cs+ gun at ca. 30 kV, and 3-nitrobenzyl alcohol (NBA) was
used in the matrix.
Preparation of Os(η5-C5H5)Cl{[η2-(E)-{Ph2(OH)C}CHd
CHCH2C(dCH2)]PiPr2} (4). A solution of Os(η5-C5H5)Cl{η2-
HCtCC(OH)Ph2}{PiPr2[C(CH3)dCH2]} (3) (91 mg, 0.14 mmol)
in 7 mL of toluene was heated to reflux for 6 h. The resulting
solution was vacuum-dried, and the residue was washed with
pentane (2 × 2 mL). A green solid was obtained. Yield: 67 mg
(74%). Anal. Calcd for C29H36ClOOsP: C, 52.99; H, 5.52.
Found: C, 53.26; H, 5.42. IR (Nujol, cm-1): ν(O-H) 3361 (s).
1H NMR (300 MHz, C6D6, 293 K): δ 8.10-6.90 (10H, Ph); 6.59
(s, 1H, OH); 5.71 (dd, 1H, JH-P ) 24.9, JH-H ) 1.2, PCdC-
Preparation of Os(η5-C5H5)Cl{[η2-(E)-PhCHdCHCH2-
C(dCH2)]PiPr2} (2). A solution of Os(η5-C5H5)Cl{[η2-CH2dC-
(CH3)]PiPr2} (1) (145 mg, 0.32 mmol) in 9 mL of toluene was
treated with PhCtCH (125 µL, 1.14 mmol) for 7 h. The
resulting solution was vacuum-dried, and the residue was
washed with pentane (3 × 3 mL). An orange solid was
obtained. Yield: 155 mg (87%). Anal. Calcd for C22H30ClOsP:
C, 47.94; H, 5.49. Found: C, 48.29; H, 5.52. 1H NMR (300 MHz,
C6D6, 293 K): δ 7.60-6.90 (5H, Ph); 5.28 (d, 1H, JH-P ) 27.0,
PCdCHtrans to P); 4.93 (d, 1H, JH-P ) 11.7, PCdCHcis to P); 4.72
(m, 1H, -CHdCHPh); 4.66 (d, 1H, JHH ) 9.9, dCHPh); 4.52
(s, 5H, η5-C5H5); 2.71 (m, 1H, one of the PCH); 2.60 (m, 1H,
one of the H in -CH2- group); 2.30 (m, 1H, one of the H in
-CH2- group); 1.87 (m, 1H, one of the PCH); 1.37 (dd, 3H,
JH-P ) 15.9, JH-H ) 7.2, one of the PCHCH3); 1.14 (dd, 3H,
JH-P ) 13.2, JH-H ) 7.2, one of the PCHCH3); 0.86 (dd, 3H,
JH-P ) 13.8, JH-H ) 7.2, one of the PCHCH3); 0.85 (dd, 3H,
JH-P ) 13.8, JH-H ) 7.2, one of the PCHCH3). 13C{1H} NMR
(75.4 MHz, C6D6, 293 K, plus APT): δ 151.9 (d, JC-P ) 38.2
Hz, P-Cd); 150.0 (s, Cipso Ph); 128.7, 125.6, and 124.9 (all s,
Ph); 117.9 (s, dCH2); 82.1 (s, η5-C5H5); 53.8 (d, JC-P ) 2.3, d
CHPh); 39.9 (s, -CHdCHPh); 39.3 (d, JC-P ) 25.3, CH2); 32.9
(d, JC-P ) 31.3, one of the PCH); 23.0 (d, JC-P ) 27.7, one of
the PCH); 21.1, 20.1, 18.6, and 18.1 (all s CH3). 31P{1H} NMR
(121.4 MHz, C6D6, 293 K): δ 42.5 (s). MS (LSIMS+): m/z )
552 (M+); 515 (M+ - Cl).
Htrans to P); 4.89 (dd, 1H, JH-P ) 10.8, JH-H ) 1.2, PCdCHcis to
P); 4.80 (d, 1H, JH-H ) 9.3, dCH-C(OH),); 4.27 (s, 5H, η5-C5H5);
4.04 (dd, 1H, JH-H ) 9.3, JH-H ) 4.8, CH2-CHdCH); 3.20 (dd,
1H, JH-P ) 31.2, JH-H ) 16.2, one of the H in CH2 group);
2.45 (m, 1H, one of the PCH); 2.19 (dd, 1H, JH-H ) 16.2, JH-H
) 4.8, one of the H in CH2 group); 1.64 (m, 1H, one of the PCH);
1.24 (dd, 3H, JH-P ) 15.3 Hz, JH-H ) 7.2, one of the PCHCH3);
1.13 (dd, 3H, JH-P ) 15.3 Hz, JH-H ) 7.2, one of the PCHCH3);
0.69 (dd, 3H, JH-P ) 15.3, JH-H ) 7.2, one of the PCHCH3);
0.45 (dd, 3H, JH-P ) 15.3, JH-H ) 7.2, one of the PCHCH3).
13C{1H} NMR (75.4 MHz, CD2Cl2, 293 K): δ 152.9, 148.0 (s,
Cipso Ph); 142.5 (d, JC-P ) 33.3, P-Cd); 128.5, 128.0, 127.4,
127.1, 126.5, and 126.4 (all s, Ph); 122.1 (s, dCH2); 83.5 (s,
η5-C5H5); 61.3 (s, COH); 57.2, and 44.0 (both s, -CHdCH-);
43.8 (d, JC-P ) 23.4, CH2); 32.7 (d, JC-P ) 33.3, one of the
PCH); 25.5 (d, JC-P ) 25.9, one of the PCH); 19.7, 18.2, 17.8,
and 16.8 (all s, CH3). 31P{1H} NMR (121.4 MHz, C6D6, 293 K):
δ 34.4 (s). MS (LSIMS+): m/z ) 658 (M+); 639 (M+ - OH);
623 (M+ - Cl); 605 (M+ - OH - Cl).
Preparation of Os(η5-C5H5)(CtCPh){[η2-CH2dC(CH3)]-
PiPr2} (5). A solution of Os(η5-C5H5)Cl{[η2-CH2dC(CH3)]PiPr2}
(1) (140 mg, 0.31 mmol) in 10 mL of tetrahydrofuran was
treated with lithium phenylacetylide (67 mg, 0.62 mmol). The
mixture was left to stir for 1 h. The resulting solution was
vacuum-dried. The residue was extracted with toluene (15 mL).
The resulting solution was vacuum-dried, and the residue was
finally washed with methanol (3 × 3 mL). A pale brown solid
was obtained. Yield: 107 mg (65%). Anal. Calcd for C22H29-
OsP: C, 51.34; H, 5.68. Found: C, 51.52; H, 5.40. IR (Nujol,
cm-1): ν(CtC) 2083 (s); ν(CdC) 1590 (m). 1H NMR (300 MHz,
C6D6, 293 K): δ 7.60-6.90 (5H, Ph); 4.72 (s, 5H, η5-C5H5); 3.48
Preparation of Os(η5-C5H5)Cl{[η2-(E)-PhCHdCDCH2C-
(dCH2)]PiPr2} (2-d1). A solution of Os(η5-C5H5)Cl{[η2-CH2dC-
(CH3)]PiPr2} (1) (8 mg, 0.018 mmol) in 0.6 mL of toluene was
treated with PhCtCD (5 µL, 0.045 mmol) for 5 h. The resulting
solution was vacuum-dried, and the residue was dissolved in
benzene-d6 (0.5 mL). 1H NMR (300 MHz, C6D6, 293 K): δ 7.60-
6.90 (5H, Ph); 5.29 (d, 1H, JH-P ) 27.0, PCdCHtrans to P); 4.93
(d, 1H, JH-P ) 11.4, PCdCHcis to P); 4.67 (s, 1H, dCHPh); 4.52
(s, 5H, η5-C5H5); 2.70 (m, 1H, one of the PCH); 2.60 (dd, 1H,
JH-P ) 14.7, JH-H ) 14.7, one of the H in CH2); 2.30 (dd, 1H,
JH-P ) 21.0, JH-H ) 14.7, one of the H in CH2); 1.87 (m, 1H,
one of the PCH); 1.37 (dd, 3H, JH-P ) 15.9 Hz, JH-H ) 7.2 Hz,
one of the PCHCH3); 1.14 (dd, 3H, JH-P ) 13.2, JH-H ) 7.2,
one of the PCHCH3,); 0.86 (dd, 3H, JH-P ) 13.8, JH-H ) 7.2,
one of the PCHCH3,); 0.85 (dd, 3H, JH-P ) 13.8, JH-H ) 7.2,
one of the PCHCH3). 2H NMR (46.1 MHz, C6H6, 293 K): δ 4.71
(s, CDdCHPh). 31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ
42.5 (s).
(dd, 1H, JH-P ) 30.3, JH-H ) 2.1, PCdCHtrans P); 2.41 (dd,
to
1H, JH-P ) 6.6, JH-H ) 2.1, PCdCHcis to P); 2.29 (m, 1H, one of
the PCH); 1.62 (m, 1H, one of the PCH); 1.40-1.00 (15H, CH3).
13C{1H} NMR (75.4 MHz, C6D6, 293 K, plus APT): δ 132.3,
128.5, 124.2 (all s, Ph); 131.3 (s, Cipso Ph); 111.5 (d, JC-P
)
3.8, Os-CtC); 85.1 (d, JC-P ) 20.3, Os-CtC); 79.4 (s, η5-C5H5);
31.2 (d, JC-P ) 18.4, P-Cd); 28.7 (d, JC-P ) 30.4, one of the
Preparation of Os(η5-C5H5)Cl{η2-HCtCC(OH)Ph2}-
{PiPr2[C(CH3)dCH2]} (3). A solution of Os(η5-C5H5)Cl{[η2-
CH2dC(CH3)]PiPr2} (1) (189 mg, 0.42 mmol) in 10 mL of
PCH); 24.3 (s, one of the CH3); 24.0 (s, dCH2); 22.7 (d, JC-P )
4.6, one of the CH3); 22.1 (d, JC-P ) 4.6, one of the CH3); 20.7
(d, JC-P ) 2.8, one of the CH3); 19.1 (d, JC-P ) 23.4, one of the

Ene Reactions Promoted by Os Fragments
Organometallics, Vol. 24, No. 9, 2005 2037
Table 3. Crystal Data and Data Collection and
Refinement for 2 and 8
obtained. Yield: 117 mg (78%). Anal. Calcd for C29H36-
ClOOsP: C, 52.99; H, 5.52. Found: C, 53.26; H, 5.42. IR (Nujol,
cm-1): ν(O-H) 3368 (s); ν(CtC) 2085 (s); ν(CdC) 1594 (m).
1H NMR (300 MHz, C6D6, 293 K): δ 7.83-6.85 (11H, Ph +
2
8
Crystal Data
OH); 5.53 (dd, 1H, JH-H ) 2.4, JH-P ) 24.3, PCdCHtrans P);
to
formula
molecular wt
color and habit
C
22H30ClOsP
C22H28ClOsP 0.5(C5H12
)
4.62 (dd, 1H, JH-H ) 2.4, JH-P ) 10.8, PCdCHcis to P); 4.06 (s,
5H, η5-C5H5); 3.60 (d, 1H, JH-H ) 9.9, CdCH); 3.43 (dd, 1H,
JH-H ) 4.5, JH-H ) 9.9, HCdC); 2.94 (dd, 1H, JH-P ) 30.3,
JH-H ) 15.6, one of the H in CH2 group); 2.11 (dd, JH-H ) 15.6,
JH-P ) 4.5, one of the H in CH2 group); 1.85 (m, 1H, PCH);
1.24 (m, 1H, PCH); 1.09 (dd, 3H, JH-P ) 15.6 Hz, JH-H ) 6.9,
551.08
orange, irregular
block
585.14
red, irregular block
symmetry, space monoclinic, P21/n
triclinic, P1h
group
a, Å
12.3343(10)
12.6118(10)
13.4358(11)
7.6298(5)
11.3416(7)
14.0086(8)
103.7850(10)
95.9700(10)
91.4870(10)
1169.30(12)
2
b, Å
one of the PCHCH3); 1.01 (dd, 3H, JH-P ) 15.3 Hz, JH-H
6.9, one of the PCHCH3); 0.43 (dd, 3H, JH-P ) 12.0, JH-H
6.6, one of the PCHCH3); 0.26 (dd, 3H, JH-P ) 14.7, JH-H
)
)
)
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
95.913(2)
7.2, one of the PCHCH3). 13C{1H} NMR (75.4 MHz, CD2Cl2,
plus APT, plus HSQC): δ 152.2, and 148.2 (both s, Cipso Ph);
144.1 (d, JC-P ) 36.9, PCd); 131.27, 128.7, 128.5, 128.3, 127.9,
127.3, 126.4, 126.3, and 124.8 (all s, Ph); 129.1 (s, Cipso Ph);
121.7 (s, dCH2); 117.5 (s, tCPh); 83.3 (s, η5-C5H5); 83.3 (s,
COH); 77.1 (d, JC-P ) 16.8, OsCt); 51.2 (s, CHd); 43.6 (d, JC-P
) 23.9, CH2); 37.6 (s, CHd); 32.0 (d, JC-P ) 32.7, PCH); 24.2
(d, JC-P ) 30.3, PCH); 19.6, 17.6, 17.2, and 16.6 (all s, CH3).
31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ 38.3 (s). MS
(LSIMS+): m/z 724 (M+ + H).
2078.9(3)
4
Dcalc, g cm-3
1.761
1.662
Data Collection and Refinement
Bruker Smart APEX
0.71073
diffractometer
λ(Mo KR), Å
monochromator
scan type
graphite oriented
ω scans
µ, mm-1
6.342
3, 57
296
5.643
3, 57
100
2θ, range, deg
temp, K
no. of data
collected
Preparation of Os(η5-C5H5)Cl{dCdCHPh}{PiPr2[C-
(CH3)dCH2]} (8). A solution of Os(η5-C5H5)Cl{[η2-CH2dC-
(CH3)]PiPr2} (1) (80 mg, 0.18 mmol) in 10 mL of toluene was
treated with NEt3 (0.15 mL, 108 mmol), and after 5 min PhCt
CH was added (125 µL, 1.14 mmol). The mixture was left to
stir for 1 h, and the resulting solution was vacuum-dried. The
residue was finally washed with pentane (3 × 4 mL), leading
to a pale red solid. The compound was purified by crystaliza-
tion: slow diffusion of pentane over a toluene solution of the
isolated solid afforded red crystals. Yield: 72 mg (73%). Anal.
Calcd for C22H30ClOsP: C, 47.94; H, 5.49. Found: C, 47.91;
H, 5.80. IR (Nujol, cm-1): ν(CdC) 1617 (s). 1H NMR (300 MHz,
C6D6, 293 K): δ 7.60-6.80 (5H, Ph); 5.26 (d, 1H, JH-P ) 31.5,
PCdCHtrans to P); 5.06 (d, 1H, JH-P ) 13.5, PCdCHcis to P); 5.05
(s, 5H, η5-C5H5); 2.82 (s, 1H, OsdCdCH); 2.56 (m, 3H, PCH);
1.83 (d, 3H, JH-P ) 9.6, PC(CH3)d); 1.10-0.90 (12H, PCHCH3).
13C{1H} NMR (75.4 MHz, C6D6, 293 K, plus APT): δ 292.6 (d,
JC-P ) 14.3, OsdC); 142.2 (d, JC-P ) 39.2, P-Cd); 131.2 (s,
24 944
44 897
no. of unique data 4983 (Rint ) 0.0729) 5449 (Rint ) 0.0283)
no. of params/
restraints
254/0
257/7
R1a[F2 > 2σ(F2)]
wR2b[all data]
Sc[all data]
0.0297
0.0402
0.655
0.0285
0.0636
1.009
a
b
2
2
R1(F) ) ∑||Fo| - |Fc||/∑|Fo|. wR2(F2) ) {∑[w(Fo - Fc )2]/
∑[w(Fo2)2]}1/2
.
Goof ) S ) {∑[Fo - Fc )2]/(n - p)}1/2, where n is
c
2
2
the number of reflections, and p is the number of refined
parameters.
PCH); 18.6 (s, one of the CH3). 31P{1H} NMR (121.4 MHz, C6D6,
293 K): δ -1.85 (s). MS (LSIMS+): m/z 515 (M+).
Preparation of Os(η5-C5H5)(CtCPh){η2-HCtCC(OH)-
Ph2}{PiPr2[C(CH3)dCH2]} (6). A solution of Os(η5-C5H5)-
(CtCPh){[η2-CH2dC(CH3)]PiPr2} (5) (180 mg, 0.35 mmol) in
6 mL of diethyl ether was treated with HCtC-C(OH)Ph2 (109
mg, 0.52 mmol) for 30 min. The resulting solution was vacuum-
dried, and the residue was washed with pentane (3 × 4 mL).
A pale yellow solid was obtained. Yield: 164 mg (65%). Anal.
Calcd for C29H36ClOOsP: C, 52.99; H, 5.52. Found: C, 53.33;
H, 5.63. IR (Nujol, cm-1): ν(O-H) 3310 (s); ν(CtC) 2075 (s);
Cipso Ph); 128.8, 125.5, and 124.8 (all s, Ph); 125.3 (d, JC-P
)
4.6, P-CdCH2); 117.0 (s, dCHPh); 88.7 (s, η5-C5H5); 25.2 (d,
JC-P ) 11.0, PCH); 20.3 (s, dCCH3); 18.5, 18.3 (both s, CH3).
31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ 19.5 (s). MS
(LSIMS+): m/z ) 552 (M+); 515 (M+ - Cl).
X-ray Analysis of 2 and 8. Two irregular crystals of size
0.12 × 0.12 × 0.10 mm (2) and 0.24 × 0.18 × 0.16 mm (8)
were mounted on a Bruker Smart APEX CCD diffractometer
at 296(2) (2) and 100.0(2) K (8) equipped with a normal focus,
2.4 kW sealed tube source (molybdenum 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 ω. The cell parameters
were determined and refined by least-squares fit of 2872 (2)
or 6550 (8) collected reflections. The first 100 frames were
collected at the end of the data collection to monitor crystal
decay. Absorption correction was performed with the SADABS
program.21 Lorentz and polarization corrections were also
performed. The structures were solved by Patterson and
Fourier methods and refined by full matrix least-squares using
the Bruker SHELXTL22 program minimizing w(Fo2 - Fc2)2. The
hydrogen atoms were observed or calculated and refined riding
to bonded carbon atoms. For 8 a molecule of disorder pentane
1
ν(CdC) 1565 (m). H NMR (300 MHz, C6D6, 293 K): δ 8.07-
7.05 (m, 15H, Ph); 5.24 (d, 1H, JH-P ) 30.3, PCdCHtrans P);
to
5.03 (d, 1H, JH-P ) 12.6, PCdCHcis to P); 4.69 (s, 5H, η5-C5H5);
4.25 (s, 1H, OH); 4.04 (d, 1H, JH-P ) 9.3, HCt); 2.48 (m, 1H,
PCH); 2.32 (m, 1H, PCH); 1.63 (d, 3H, JH-P ) 8.7, PC(CH3)));
1.09 (dd, 3H, JH-H ) 7.5, JH-P ) 15.0, PCHCH3); 0.86 (dd, 3H,
JH-H ) 7.3, JH-P ) 12.5, PCHCH3). 13C{1H} NMR (75.4 MHz,
C6D6, plus APT, plus HSQC): δ 149.6, 148.9 (both s, Cipso);
143.2 (d, JC-P ) 36.9, PCd); 132.1, 128.4, 128.3, 128.1, 127.2,
127.0, and 126.9 (all s, Ph); 129.6 (s, Cipso); 125.3 (s, HCt);
124.5 (s, dCH2); 116.5 (s, tCPh); 83.0 (s, η5-C5H5); 79.6 (s,
CPh2OH); 78.3 (d, JC-P ) 21.6, OsCt); 75.7 (s, HCtC-C(OH));
27.2 (d, JC-P ) 31.7, PCH); 25.5 (d, JC-P ) 33.5, PCH); 20.3 (s,
PC(CH3)); 20.2 and 19.4 (both s, CH3). 31P{1H} NMR (121.4
MHz, C6D6, 293 K): δ 20.3 (br s). MS (LSIMS+): m/z 724 (M+
+ H).
Preparation of Os(η5-C5H5)(CtCPh){[η2-(E)-{Ph2(OH)C}-
CHdCHCH2C(dCH2)]PiPr2} (7). A solution of Os(η5-C5H5)-
(CtCPh){η2-HCtCC(OH)Ph2}{PiPr2[C(CH3)dCH2]} (6) (150
mg, 0.21 mmol) in 7 mL of toluene was heated to reflux for 6
h. The resulting solution was vacuum-dried, and the residue
was washed with pentane (2 × 2 mL). A white solid was
(21) Blessing, R. H. Acta Crystallogr., Sect. A 1995, 51, 33. SADABS,
Area-detector absorption correction; Bruker-AXS: Madison, WI,
1996.
(22) SHELXTL Package, v. 6.1; Bruker Analytical, X-ray Systems:
Madison, WI, 2000.

2038 Organometallics, Vol. 24, No. 9, 2005
Baya et al.
was observed in the unit cell. Weighted R factors (Rw) and
goodness of fit (S) are based on F2, and conventional R factors
are based on F.
ish MCYT/Universidad de Zaragoza for funding through
the “Ramo´n y Cajal” program.
Supporting Information Available: Tables of crystal-
lographic data and bond lengths and angles. This material is
available free of charge via the Internet at http://pubs.acs.org.
Acknowledgment. Financial support from the
MCYT of Spain (Project BQU2002-00606, PPQ2000-
0488-P4-02) is acknowledged. M.L.B. thanks the Span-
OM0489857