Synthesis and reactivity of osmium complexes containing a cyclopentadienyl ligand with a pendant phosphine donor group

Article abstract of DOI:10.1021/om049904+

The unsaturated six-coordinate complex OsH²Cl₂(P ⁱPr₃)₂ (1) reacts with Li[C₅H ₄(CH₂)₂PPh₂] to give [OsH ₂{η⁵-C₅H₄(CH₂) ₂PPh₂}(PⁱPr₃)]Cl (2). This dihydride is fairly acidic and can be deprotonated with KOH in methanol. The reaction of the resulting monohydride OsH-{η⁵-C₅H ₄(CH₂)₂PPh₂}(P_iPr ₃) (3) with chloroform affords Os{η⁵-C ₅H₄(CH₂)₂PPh₂}Cl(P ⁱPr₃) (4). The extraction of the chloride ligand with TIPF₆ causes the selective C-H activation of one of the methyl groups of the triisopropylphosphine ligands to give [{CH₂CH(CH ₃P_iPr₂}OsH-{⁵-C₅H ₄(CH₂)₂PPh₂}]PF₆(5), which is isolated as a mixture of stereoisomers. Complex 4 also reacts with phenylacetylene in the presence of TlPF₆. The reaction leads to the hydride-alkynyl-osmium(IV) derivative [OsH{η⁵-C₅H ₄(CH₂)₂PPh₂}(C≡CPh)(P ⁱPr₃)]PF₆ (6), which is not stable and evolves into the vinylidene [OsH{η⁵-C₅H₄(CH ₂)₂PPh₂}(=C=CHPh)(PⁱPr ₃)]PF₆ (7). Deprotonation of 7 with methanol solutions of KOH yields the neutral alkynyl compound [OsH{η⁵-C ₅H₄(CH₂)₂PPh₂} (C≡CPh)(PⁱPr₃)] (8). The addition of HPF ₆·H₂O to 8 regenerates 7. Similarly to phenylacetylene, 1,1-diphenyl-2-propyn-l-ol reacts with 4 and TIPF₆ to give the hydride-hydroxyalkynyl derivative [OsH{η⁵-C ₅H₄(CH₂)₂PPh₂} {C≡CC)(OH)Ph₂ⁱPr₃)]-PF₆ PF₆ (9), which dehydrates to produce the allenylidene [OsH{η⁵-C₅H₄(CH₂) ₂PPh₂}(=C=C=CPh₂)(PⁱPr ₃)]PF₆ (10). Addition of HPF₆·H ₂O to 10 affords the dicationic alkenyl carbyne [Os{η⁵-C₅H₄(CH₂) ₂PPh₂}(≡CCH=CPh₂)(PⁱPr ₃)](PF₆)₂ (11). Complexes 2 and 4 have been characterized by X-ray diffraction analysis.

Full text of DOI:10.1021/om049904+

Organometallics 2004, 23, 3021-3030
3021
Syn th esis a n d Rea ctivity of Osm iu m Com p lexes
Con ta in in g a Cyclop en ta d ien yl Liga n d w ith a P en d a n t
P h osp h in e Don or Gr ou p
Miguel A. Esteruelas,* Ana M. Lo´pez, Enrique On˜ate, and Eva Royo
Departamento de Quı´mica Inorga´nica, Instituto de Ciencia de Materiales de Arago´n,
Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
Received February 5, 2004
The unsaturated six-coordinate complex OsH2Cl2(PiPr3)2 (1) reacts with Li[C5H4(CH2)2-
PPh2] to give [OsH2{η5-C5H4(CH2)2PPh2}(PiPr3)]Cl (2). This dihydride is fairly acidic and
can be deprotonated with KOH in methanol. The reaction of the resulting monohydride OsH-
{η5-C5H4(CH2)2PPh2}(PiPr3) (3) with chloroform affords Os{η5-C5H4(CH2)2PPh2}Cl(PiPr3) (4).
The extraction of the chloride ligand with TlPF6 causes the selective C-H activation of one
of the methyl groups of the triisopropylphosphine ligands to give [{CH2CH(CH3)PiPr2}OsH-
{η5-C5H4(CH2)2PPh2}]PF6 (5), which is isolated as a mixture of stereoisomers. Complex 4
also reacts with phenylacetylene in the presence of TlPF6. The reaction leads to the hydride-
alkynyl-osmium(IV) derivative [OsH{η5-C5H4(CH2)2PPh2}(CtCPh)(PiPr3)]PF6 (6), which is
not stable and evolves into the vinylidene [Os{η5-C5H4(CH2)2PPh2}(dCdCHPh)(PiPr3)]PF6
(7). Deprotonation of 7 with methanol solutions of KOH yields the neutral alkynyl compound
[Os{η5-C5H4(CH2)2PPh2}(CtCPh)(PiPr3)] (8). The addition of HPF6‚H2O to 8 regenerates 7.
Similarly to phenylacetylene, 1,1-diphenyl-2-propyn-1-ol reacts with 4 and TlPF6 to give
the hydride-hydroxyalkynyl derivative [OsH{η5-C5H4(CH2)2PPh2}{CtCC(OH)Ph2}(PiPr3)]-
PF6 (9), which dehydrates to produce the allenylidene [Os{η5-C5H4(CH2)2PPh2}(dCdCd
CPh2)(PiPr3)]PF6 (10). Addition of HPF6‚H2O to 10 affords the dicationic alkenyl carbyne
[Os{η5-C5H4(CH2)2PPh2}(tCCHdCPh2)(PiPr3)](PF6)2 (11). Complexes 2 and 4 have been
characterized by X-ray diffraction analysis.
In tr od u ction
properties of the active systems and facilitates the study
of the catalytic mechanisms.3
Cyclopentadienyl ligands bearing pendant donor
groups are attracting increased interest in the chemistry
of the metals.1 The complexes containing this type of
ligands are expected to perform chemistry different from
that of usual cyclopentadienyl complexes. Indeed, the
reversible coordination-decoordination of the pendant
donor group facilitates the stabilization of highly reac-
tive centers.2 This has a strong influence on the catalytic
For the iron triad, the chemistry of the half-sandwich
osmium complexes with the pentamethylcyclopentadi-
enyl4 and particularly cyclopentadienyl5 ligands is a
field much less known than the chemistry of related
half-sandwich iron and ruthenium compounds.6 In ac-
cordance with this, a significant number of phosphi-
noalkylcyclopentadienyl complexes of iron and ruthe-
nium have been prepared by a variety of methods,1c
while the osmium counterparts are unknown.
* Corresponding author. E-mail: maester@posta.unizar.es.
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10.1021/om049904+ CCC: $27.50 © 2004 American Chemical Society
Publication on Web 05/05/2004

3022 Organometallics, Vol. 23, No. 12, 2004
Esteruelas et al.
The limited development of the chemistry of the Os-
(η5-C5H5) unit is in part due to the lack of convenient
Os(η5-C5H5) starting complexes5a,b,7 and the greater
inertness of the Os(η5-C5H5)L3 species in comparison
with the related ruthenium derivatives.8 Seven years
ago, we reported that the six-coordinate complex OsH2-
Cl2(PiPr3)2 reacts with Tl(C5H5) to afford the cyclopen-
tadienyl compound Os(η5-C5H5)Cl(PiPr3)2,9 which allows
the development of new cyclopentadienyl osmium chem-
istry.10 Despite the high kinetic inertness of the Os(η5-
C5H5)L3 systems, the complex Os(η5-C5H5)Cl(PiPr3)2
dissociates the chloride ligand in methanol, and the
resulting fragment is capable of activating a methyl
C-H bond of one of the triisopropylphosphine ligands
romethane the bis(triphenylphosphine) derivative Os-
(η5-C5H5)(OTf)(PPh3)2 evolves in a similar way into the
orthometalated species [OsH{η5-C5H5)(PPh2C6H4)(PPh3)]-
OTf.11
Although the arene C-H bond is between 14 and 8
kcal‚mol-1 stronger than the alkane C-H bond, in
general, the activation of the first one is kinetically and
thermodynamically favored. The kinetic advantage of
the arene activation appears to be due to its prior
π-coordination, while the thermodynamic preference has
been largely attributed to a metal-carbon bond much
stronger for aryl than for alkyl.12 In agreement with the
preferred arene C-H activation, the mixed-phosphine
ligand complex Os(η5-C5H5)Cl(PPh3)(PiPr3) reacts with
to give [OsH{η5-C5H4{CH2CH(CH3)PiPr2}(PiPr3)]+, as a
mixture of two pairs of diastereoisomers.9 Previously,
Tilley and co-workers had observed that in dichlo-
thallium hexafluorophosphate to give [OsH{η5-C5H5)-
(PPh2C6H4)(PiPr3)]PF6 as a result of the selective acti-
vation of a phenyl ring in the presence of the alkyl
groups of the triisopropylphosphine.10d
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When terminal alkynes and alkynols are present, the
H-C(sp) activation of the organic substrate is favored
with regard to the intramolecular activation of the
phosphine ligands. According to this, treatment of Os-
(η5-C5H5)Cl(PiPr3)2 with thallium hexafluorophosphate
and terminal alkynes or alkynols leads to hydride-
alkynyl-osmium(IV) complexes, [OsH(η5-C5H5)(CtCR)(Pi-
Pr3)2]PF6, as a result of the H-C(sp) oxidative addition
of the alkyne or alkynol to the [Os(η5-C5H5)(PiPr3)2]+
metallic fragment.10e In contrast to the ruthenium
analogues,13 these compounds are stable under the
reaction conditions and do not evolve spontaneously into
the corresponding cumulenes. The formation of vi-
nylidene or allenylidene derivatives requires the depro-
tonation of the hydride-alkynyl-osmium(IV) compounds
with strong bases and the subsequent protonation of the
resulting alkynyl-osmium(II) complexes.10e,h
We are interested in getting information about how
the presence of a donor group tied to the cyclopentadi-
enyl ring influences the chemistry of half-sandwich
cyclopentadienyl osmium complexes. This led us to
wonder whether the six-coordinate compound OsH2-
Cl2(PiPr3)2 could be also useful to prepare osmium
derivatives containing a cyclopentadienyl ligand bearing
a pendant phosphino group. In this paper, we report the
first osmium complexes with a ligand of this type,
2-diphenylphosphinoethylcyclopentadienyl. Further-
more, we show the influence of the CH2CH2 chain on
the competitive alkane-arene intramolecular C-H ac-
tivation and the influence of the diphenylphosphino
group on the stability of hydride-alkynyl-osmium(IV)
species.
Resu lts a n d Discu ssion
1. Rea ction of OsH2Cl2(P iP r 3)2 w ith Li[C5H4-
(CH 2)2P P h 2]. The dihydride-dichloro complex OsH2-
(11) Wanandi, P. W.; Tilley, T. D. Organometallics 1997, 16, 4299.
(12) J ones, W. D.; Feher, F. J . Acc. Chem. Res. 1989, 22, 91.
(13) (a) de los R´ıos, I.; J ime´nez-Tenorio, M.; Puerta, M. C.; Valerga,
P. J . Chem. Soc., Chem. Commun. 1995, 1757. (b) de los R´ıos, I.;
J ime´nez-Tenorio, M.; Puerta, M. C.; Valerga, P. J . Am. Chem. Soc.
1997, 119, 6529. (c) Bustelo, E.; J ime´nez-Tenorio, M.; Puerta, M. C.;
Valerga, P. Organometallics 1999, 18, 950. (d) Bustelo, E.; J ime´nez-
Tenorio, M.; Puerta, M. C.; Valerga, P. Organometallics 1999, 18, 4563.
(e) Aneetha, H.; J ime´nez-Tenorio, M.; Puerta, M. C.; Valerga, P.;
Mereiter, K. Organometallics 2003, 22, 2001.

Os Complexes Containing a Cyclopentadienyl Ligand
Organometallics, Vol. 23, No. 12, 2004 3023
Ta ble 1. Selected Bon d Dista n ces (Å) a n d An gles (d eg) for [OsH2{η5-C5H4(CH2)2P P h 2}(P iP r 3)]Cl (2)
molecule a
molecule b
molecule a
molecule b
Os(1)-P(1)
2.2746(19)
2.3157(18)
1.37(6)
1.46(6)
2.233(7)
2.176(7)
111.98(7)
115(3)
2.2664(19)
2.3191(19)
1.33(6)
1.46(6)
2.204(7)
2.177(6)
111.82(7)
133(3)
Os(1)-C(3)
2.241(7)
2.258(7)
2.249(7)
1.494(10)
1.521(9)
1.840(7)
65(2)
109.0(5)
100.8(2)
112.6(6)
2.251(7)
2.283(7)
2.255(7)
1.509(10)
1.529(9)
1.844(7)
77(2)
107.9(5)
101.5(2)
113.8(6)
Os(1)-P(2)
Os(1)-C(4)
Os(1)-H(1)
Os(1)-C(5)
Os(1)-H(2)
C(1)-C(6)
Os(1)-C(1)
C(6)-C(7)
Os(1)-C(2)
C(7)-P(1)
P(1)-Os(1)-P(2)
H(1)-Os(1)-H(2)
H(1)-Os(1)-P(1)
H(1)-Os(1)-P(2)
H(2)-Os(1)-P(1)
H(2)-Os(1)-P(2)
C(6)-C(7)-P(1)
C(7)-P(1)-Os(1)
C(1)-C(6)-C(7)
90(3)
63(2)
75(2)
65(3)
79(3)
87(2)
Sch em e 1
Figu r e 1. Molecular diagram of [OsH2{η5-C5H4(CH2)2PPh2}
(PiPr3)]Cl (2). Thermal ellipsoids are shown at 50% prob-
ability.
with the transoid disposition of the hydride ligands, the
1H NMR spectrum in dichloromethane-d2 contains only
one hydride resonance at -13.10 ppm, which is observed
as a double doublet with P-H coupling constants of 25.5
and 30.9 Hz. In addition, the spectrum reflects the
rigidity of the CH2-CH2 chain, which is a consequence
of the coordination of the phosphorus atom of the
pendant group to the metallic center. Thus, it shows an
AA′BB′X spin system between 3.85 and 2.09 ppm for
the methylene protons. The 31P{1H}NMR spectrum
displays two doublets at 44.7 and 30.1 ppm, with a P-P
coupling constant of 30 Hz.
Cl2(PiPr3)2 (1) is certainly useful to prepare compounds
containing a 2-diphenylphosphinoethylcyclopentadienyl
ligand. At room temperature, the reaction of 1 with
Li[C5H4(CH2)2PPh2] in toluene leads, after 12 h, to
the dihydride-osmium(IV) derivative [OsH2{η5-C5H4-
(CH2)2PPh2}(PiPr3)]Cl (2), in 64% yield (Scheme 1).
The coordination of the diphenylphosphino group to
the metallic center of 2 was confirmed by an X-ray
diffraction study. The structure has two chemically
equivalent but crystallographically independent mol-
ecules in the asymmetric unit. A drawing of one of them
is shown in Figure 1. Selected bond distances and angles
for both molecules are listed in Table 1.
Complex 2 can be deprotonated by reaction with a
methanol solution of potassium hydroxide. The addition
of this base to tetrahydrofuran solutions of 2 gives rise
to the formation of the neutral compound [OsH{η5-C5H4-
(CH2)2PPh2}(PiPr3) (3), as a result of the extraction of
one of the hydride ligands. Complex 3 was isolated as a
yellow oil in a 98% yield. Due to the chirality of the
The distribution of ligands around the osmium atom
can be described as a four-legged piano stool geometry,
with the cyclopentadienyl ring occupying the three-
membered face while the phosphorus donor atoms lie
in the four-membered face mutually transoid disposed.
The P(1)-Os-P(2) bond angle is 111.98(7)° for molecule
a and 111.82(7)° for molecule b. Interestingly, the Os-
PPh2 bond appears to be stronger than the Os-PiPr3
bond. Thus, the Os(1)-P(1) bond length (2.2746(19) Å
in molecule a and 2.2664(19) Å in molecule b) is about
0.04 Å shorter than the Os(1)-P(2) distance (2.3157-
(18) Å in molecule a and 2.3191(19) Å in molecule b).
1
osmium atom, the H NMR spectrum of 3 in benzene-
d6 shows an ABCDX spin system for the methylene
resonances, which appear between 3.08 and 1.69 ppm,
whereas the hydride signal is observed at -14.40 ppm
as a double doublet with P-H coupling constants of 21.6
and 32.7 Hz. The 31P{1H} NMR spectrum shows two
doublets at 41.7 and 27.9 ppm, with a P-P coupling
constant of 5 Hz.
In chloroform, complex 3 is unstable and evolves into
1
The IR and the H and 31P{1H} NMR spectra of 2 are
the chloro derivative [Os{η5-C5H4(CH2)2PPh2}Cl(PiPr3)
(4), which is analogous to the mixed-ligand complex Os-
(η5-C5H5)Cl(PPh3)(PiPr3) but with the PPh2-phosphorus
atom connected to the cyclopentadienyl ring.
consistent with the structure shown in Figure 1. In the
IR spectrum in Nujol, the most noticeable feature is the
presence of a ν(Os-H) band at 2133 cm-1. In agreement

3024 Organometallics, Vol. 23, No. 12, 2004
Esteruelas et al.
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles (d eg) for Os{η5-C5H4(CH2)2P P h 2}Cl(P iP r 3) (4)
molecule a
molecule b
molecule a
molecule b
Os(1)-P(1)
2.2816(12)
2.3443(12)
2.4489(11)
2.178(4)
2.193(4)
2.215(4)
101.04(4)
99.06(4)
87.43(4)
2.2792(12)
2.3552(12)
2.4555(11)
2.181(4)
2.197(4)
2.217(4)
100.52(4)
99.75(4)
88.09(4)
Os(1)-C(4)
Os(1)-C(5)
C(1)-C(6)
C(6)-C(7)
C(7)-P(1)
2.239(4)
2.199(4)
1.501(6)
1.524(5)
1.847(4)
2.235(4)
2.194(4)
1.495(5)
1.532(5)
1.846(4)
Os(1)-P(2)
Os(1)-Cl
Os(1)-C(1)
Os(1)-C(2)
Os(1)-C(3)
P(1)-Os(1)-P(2)
P(1)-Os(1)-Cl
P(2)-Os(1)-Cl
C(7)-P(1)-Os(1)
C(6)-C(7)-P(1)
C(1)-C(6)-C(7)
102.10(15)
106.2(3)
111.6(3)
102.59(14)
106.1(3)
110.4(3)
CH2-CH2 chain. This strongly supports the coordina-
tion of the phosphorus atom to the metallic center in
solution, even at high temperature. In accordance with
it, the 31P{1H} NMR spectrum exhibits two doublets at
11.4 and 7.4 ppm with a P-P coupling constant of 13
Hz.
2. Com p etitive Alk a n e-Ar en e In tr a m olecu la r
C-H Activa tion in 4. Similarly to the mixed-phos-
phine ligand complex Os(η5-C5H5)Cl(PPh3)(PiPr3), the
chloride ligand of 4 can be extracted from the osmium
atom with thallium hexafluorophosphate. The resulting
metallic center is capable of activating a C-H bond of
one of the substituents of the phosphine ligands. How-
ever, in this case, the C-H activation does not take
place on a phenyl group, as it is observed for Os(η5-
C5H5)Cl(PPh3)(PiPr3), but on an isopropyl group. Thus,
at room temperature, the treatment of 4 with 1.0 equiv
of thallium hexafluorophosphate in acetone affords the
Figu r e 2. Molecular diagram of [Os{η5-C5H4(CH2)2PPh2}Cl
(PiPr3) (4). Thermal ellipsoids are shown at 50% probability.
Complex 4 was isolated as a yellow solid in 79% yield
and characterized by MS, elemental analysis, IR, and
1H, 31P{1H}, and 13C{1H} NMR spectroscopy as well as
by an X-ray crystallographic study. Analogously to
compound 2, the structure of 4 has two chemically
equivalent but crystallographically independent mol-
ecules in the asymmetric unit. A drawing of one of them
is shown in Figure 2. Selected bond distances and angles
for both molecules are listed in Table 2.
yellow metalated derivative [{CH2CH(CH3)iPr2P}OsH-
{η5-C5H4(CH2)2PPh2}]PF6 (5). Complex 5 was isolated
as a 1:1 mixture of the stereoisomers 5a and 5b shown
in eq 1, in 94% yield.
The geometry around the osmium center can be
described as a very distorted octahedron, with the
cyclopentadienyl ring occupying the three sites of a face.
i
The Pr3P-Os-Cl angle (87.43(4)° for molecule a and
88.09(4)° for molecule b) is close to 90°. However, the
P-Os-P (101.04(4)° for molecule a and 100.52(4)° for
molecule b) and Ph2P-Os-Cl (99.06(4)° for molecule a
and 99.75(4)° for molecule b) angles strongly deviate
from the ideal value of 90°. This suggests that the
distortion of the octahedron is in part due to the
constriction imposed by the CH2-CH2 string in the
2-diphenylphosphinoethylcyclopentadienyl ligand. How-
ever, this constriction does not appear to give rise to an
Os-PPh2 bond less stable than the Os-PiPr3 bond. In
fact, in a manner similar to 2, the Os-PPh2 bond seems
to be even stronger than the Os-PiPr3 one. Thus, the
distance between the metal center and the phosphorus
atom of the diphenylphosphinoethyl group of 4 (Os(1)-
P(1) ) 2.2816(12) (a ), 2.2792(12) (b) Å) is about 0.06 Å
shorter than the Os-PiPr3 bond length (Os(1)-P(2) )
2.3443(12) (a ), 2.3552(12) (b) Å).
The formation of 5 is a rare case of selective alkyl
C-H activation in the presence of phenyl groups, which
is in contrast with the kinetic and thermodynamic
preference of the C-H arene activation over the C-H
alkyl one. It is easily seen by using a molecular model
that the constriction imposed by the CH2-CH2 chain
in the functionalized cyclopentadienyl ligand should not
influence significantly the stability of the orthometa-
lated ring, resulting from the aryl C-H activation. So,
we assume that the isopropyl C-H activation in 4 is
kinetic in origin. In agreement with this, it has been
previously observed that the short-lived ruthenium(0)
species Ru(η6-C6Me6)(PPh2R) (R ) iPr, tBu), containing
an alkyldiphenylphosphine ligand, evolve initially into
cyclometalated complexes, as a result of the C-H
activation of the alkyl substituent. In solution, these
1
The H and 31P{1H} NMR spectra of 4 are consistent
with the structure shown in Figure 2 and with the high
1
stability of the [Os{η5-C5H4(CH2)2PPh2} unit. In the H
NMR spectrum, which is temperature invariant be-
tween -80 and 80 °C, the most noticeable feature is the
presence between 3.18 and 1.37 ppm of an ABCDX spin
system corresponding to the methylene protons of the

Os Complexes Containing a Cyclopentadienyl Ligand
Organometallics, Vol. 23, No. 12, 2004 3025
Sch em e 2
cyclometalated species rapidly isomerize into the ther-
modynamically favored aryl orthometalated deriva-
tives.14
As it has been previously mentioned, the kinetic
advantage of the arene activation is related to its prior
π-coordination. For arylphosphine ligands, the coordina-
tion of the phosphorus atom to the metal makes the
π-coordination of the aryl group unfavorable. As a result,
the barrier for the aryl activation increases with regard
to the barrier of the simple arene activation. The rise
can locate the aryl activation barrier over the alkyl
activation one. In this case, the kinetic advantage for
the arene activation disappears and the weaker alkyl
C-H bond is initially activated. In contrast to the
previously mentioned metalated ruthenium derivatives,
complex 5 does not evolve into an orthometalated
isomer. This suggests that the increase of the activation
barrier for the arene activation in the case of arylphos-
phines is associated with the prior dissociation of the
M-P bond. Thus the strength of the Os-PPh2 bond in
(dCdCHR)(PPh3)2]PF6 (R ) H, CH2(CH2)2CH2OH, tBu,
the [Os{η5-C5H4(CH2)2PPh2} moiety could explain why
5 does not evolve into an orthometalated isomer.
CdC(CH2)nCH2),17 and [Os{η5-C5H5)(dCdCHR)(PiPr3)2]-
PF6 (R ) Ph, Cy).10h The procedure used for the
preparation of these complexes and related ruthenium
derivatives involves the treatment of the corresponding
chloro starting materials with terminal alkynes in the
presence of NH4PF6, NaBPh4, or analogous salts.13,18
From a mechanistic point of view, it has been proposed
that the reactions proceed via 1,2-hydrogen migration
on a M(η2-alkyne) intermediate or, alternatively, through
hydride-alkynyl species.13,18,19 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 a metal-alkynyl species.13b For the
osmium-bis(triisopropylphosphine) system, the high
basicity of the alkynyl complexes of general formula Os-
(η5-C5H5)(CtCR)(PiPr3)2 imposes a high energy for the
dissociation of H+ from [OsH(η5-C5H5)(CtCR)(PiPr3)2]+,
which makes nonviable the hydride-alkynyl isomeriza-
tion into the vinylidene derivative.10h
In solution, the presence of isomers 5a and 5b is
strongly supported by the 1H, 13C{1H}, and 31P{1H}
1
NMR spectra of 5. In the H NMR spectrum in acetone-
d6, the hydride resonances appear at -12.38 and -12.84
ppm as double doublets with H-P coupling constants
of 31.2 and 25.8 Hz and 29.7 and 25.2 Hz, respectively.
Similar P-H coupling constants have been observed for
the monohydride derivatives RuH(η5-C5Me5){CH2CH-
(CH3)PiPr2}{Si(CH3)Ph2} (22.5 Hz)15 and [OsH{η5-C5H5-
(PPh2C6H4)(PiPr3)]PF6 (35.7 and 26.4 Hz),10d whose
cisoid-(P,H) four-legged piano-stool geometries have
been determined by X-ray diffraction studies. In the 13C-
{1H} NMR spectrum, the Os-CH2 and PCH signals of
the metalated isopropyl group are observed at -22.5 and
-24.3 ppm and 46.6 and 43.4 ppm, respectively. These
chemical shifts agree well with those previously re-
The replacement of a triisopropylphosphine ligand
and the cyclopentadienyl group by the 2-diphenylphos-
phinoethylcyclopentadienyl ligand increases the acidity
of the hydride-alkynyl intermediate. At -20 °C, the
treatment of 4 with phenylacetylene in the presence of
ported for the complexes [OsH(η5-C5H5){CH2CH(CH3)Pi-
Pr2}(PiPr3)]PF6 (-36.9 and -37.4 ppm and 49.9 and
46.9 ppm),9 RuH(η5-C5Me5){CH2CH(CH3)PiPr2}{Si(CH3)-
Ph2} (-31.5 and 42.8 ppm),15 and RuH(η6-C6H6){CH2-
thallium hexafluorophosphate initially leads to [OsH-
CH(CH3)PiPr2} (-10.74 and 42.80 ppm).16 The 31P{1H}
NMR spectrum shows four doublets at 33.0 and -17.3
and 31.3 and -11.1 ppm, with P-P coupling constants
of 31 and 25 Hz, respectively.
{η5-C5H4(CH2)2PPh2}(CtCPh)(PiPr3)]PF6 (6). However,
in contrast to that observed for [OsH(η5-C5H5)(CtCPh)
(PiPr3)2]PF6, compound 6 isomerizes into the vinylidene
[Os{η5-C5H4(CH2)2PPh2}(dCdCHPh)(PiPr3)]PF6
(7)
3. Rea ction of 4 w ith TlP F 6 a n d HCtCP h . Cat-
ionic half-sandwich osmium vinylidene complexes are
very scarce. The compounds of this type previously
reported include [Os{η5-C5Me5)(dCdCHR)(CO)(PPh3)]-
PF6 (R ) tBu, Ph),4b [Os(η5-C5H5)(dCdCHR)(CO)
(Scheme 2). In acetone at room temperature, the trans-
formation is quantitative after 12 h.
(17) Gamasa, M. P.; Gimeno, J .; Gonza´lez-Cueva, M.; Lastra, E. J .
Chem. Soc., Dalton Trans. 1996, 12, 2547.
(18) See for example: (a) Lagadec, R. L.; Roman, E.; Toupet, L.;
Mu¨ller, U.; Dixneuf, P. H. Organometallics 1994, 13, 5030. (b)
Cadierno, V.; Gamasa, M. P.; Gimeno, J .; Pe´rez-Carren˜o, E.; Garc´ıa-
Granda, S. Organometallics 1999, 18, 2821.
(PiPr3)]BF4 (R ) Ph, CdC(CH2)3CH2),7c [Os(η5-C9H7)
(14) Bennett, M. A.; Huang, T.-N.; Latten, J . L. J . Organomet. Chem.
1984, 272, 189.
(15) Campion, B. K.; Heyn, R. H.; Tilley, T. D.; Rheingold, A. L. J .
Am. Chem. Soc. 1993, 115, 5527.
(16) Kletzin, H.; Werner, H. Angew. Chem., Int. Ed. Engl. 1983, 22,
873.
(19) See for example: (a) Silvestre, J .; Hoffmann, R. Helv. Chim.
Acta 1985, 6, 1461. (b) Bruce, M. I. Organometallics 1991, 10, 197. (c)
Wakatsuki, Y.; Koga, N.; Yamazaki, H.; Morokuma, K. J . Am. Chem.
Soc. 1994, 116, 8105. (d) Wakatsuki, Y.; Koga, N.; Werner, H.;
Morokuma, K. J . Am. Chem. Soc. 1997, 119, 360. (e) Stegmann, R.;
Frenking, G. Organometallics 1998, 17, 2089.

3026 Organometallics, Vol. 23, No. 12, 2004
Esteruelas et al.
Sch em e 3
The presence of a hydride ligand in 6 is supported by
the H NMR spectrum in acetone-d6, which contains a
1
double doublet at -12.35 ppm, with H-P coupling con-
stants of 36.9 and 26.4 Hz. In the low-field region of
the spectrum, the most noticeable feature is the pres-
ence, between 4.26 and 2.10 ppm, of the ABCDX spin
system due to the methylene protons of the 2-di-
phenylphosphinoethylcyclopentadienyl ligand. In the
13C{1H} NMR spectrum, the resonances corresponding
to the C(sp) carbon atoms of the alkynyl group are ob-
served at 115.4 and 65.6 ppm. The first of them, due to
the Câ carbon atom, appears as a broad signal, while
the second one assigned to the CR carbon atom is
observed as a double doublet with both C-P coupling
constants of 25 Hz.
The vinylidene complex 7 was isolated as a red solid
1
in 82% yield. The H NMR spectrum shows the reso-
nance due to the dCH proton of the vinylidene ligand
at 3.43 ppm as a doublet with a P-H coupling constant
of 3 Hz. The ABCDX spin system due to the CH2-CH2
chain is observed between 3.98 and 1.94 ppm. In the
13C{1H} NMR spectrum, the CR carbon atom of the
vinylidene unit displays a double doublet at 309.5 ppm,
with C-P coupling constants of 6 and 13 Hz, whereas
the resonance corresponding to the Câ atom appears as
a singlet at 115.2 ppm. The 31P{1H} NMR spectrum
shows two doublets at 20.7 and 15.9 ppm, with a P-P
coupling constant of 12 Hz.
the alkynol H-C(sp) bond to the unsaturated [Os{η5-
C5H4(CH2)2PPh2}(PiPr3)]+ metallic fragment (Scheme 3).
1
In the H NMR spectrum, the most noticeable reso-
nance of the hydroxyalkynyl ligand is a broad signal
centered at 2.96 ppm, which was assigned to the OH
proton. In the high-field region of the spectrum the
hydride ligand gives rise to a double doublet at -12.54
ppm. In agreement with the cisoid disposition of the
hydride to both phosphorus atoms10d,e the H-P coupling
constants are 37.2 and 26.7 Hz. In the 13C{1H} NMR
spectrum, the resonance due to the CR carbon atom of
the hydroxyalkynyl ligand appears at 60.3 ppm as a
double doublet with both C-P coupling constants of 24
Hz, whereas that corresponding to the Câ carbon atom
is observed at 116.0 ppm also as a double doublet but
with both C-P coupling constants of 3 Hz. The 31P{1H}
NMR spectrum contains two doublets at 25.6 and 13.9
ppm, with a P-P coupling constant of 34 Hz.
The replacement of a triisopropylphosphine ligand
and the cyclopentadienyl ring by the 2-diphenylphos-
phinoethylcyclopentadienyl group also produces an
increase of the acidity of the hydride-hydroxyalkynyl-
osmium(IV) complexes. The fact becomes apparent when
compound 9 is compared with the related bis(triisopro-
pylphosphine) derivative [OsH(η5-C5H5){CtCC(OH)-
Ph2}(PiPr3)2]PF6. In contrast to the latter but in agree-
ment with 6, complex 9 is unstable and evolves into
Because the rate-determining step for the isomeriza-
tion of the hydride-alkynyl to the vinylidene is the H+
dissociation from the hydride-alkynyl and, therefore, the
protonation of the neutral alkynyl intermediate is very
fast,10h the Os{η5-C5H4(CH2)2PPh2}(CtCPh)(PiPr3) (8)
species was not detected during the isomerization of 6
into 7. However, compound 8 can be prepared by
deprotonation of the vinylidene ligand of 7 with potas-
sium hydroxide in methanol (Scheme 2). In agreement
with the higher stability of 7 with regard to 6, the
addition of 1.2 equiv of HPF6‚H2O to diethyl ether
solutions of 8 produces the instantaneous precipitation
of 7 in almost quantitative yield.
Intermediate 8 was obtained as a pale yellow solid in
88% yield. In the IR spectrum in Nujol of this complex,
the most noticeable feature is the ν(CtC) vibration,
1
which is observed at 2059 cm-1. The H NMR spectrum
shows the ABCDX spin system due to the CH2CH2
fragment of the 2-diphenylphosphinoethylcyclopenta-
dienyl ligand between 3.09 and 1.43 ppm. In the 13C{1H}
NMR spectrum, the C(sp) resonances of the alkynyl
ligand are observed as broad signals at 110.7(Câ) and
94.5(CR) ppm. The 31P{1H} NMR spectrum exhibits two
doublets at 17.2 and 9.3 ppm, with a P-P coupling
constant of 11 Hz.
the allenylidene derivative [Os{η5-C5H4(CH2)2PPh2}-
(dCdCdCPh2)(PiPr3)]PF6 (10). In acetone solution at
room temperature, the transformation is quantitative
after 12 h. According to that observed for half-sandwich
ruthenium systems,13 the dehydration of 9 to give 10
should involve the formation of a hydroxyvinylidene
intermediate.
Complex 10 was isolated as a very dark yellow solid
in 88% yield. The presence of the allenylidene ligand in
this derivative is strongly supported by the IR and
13C{1H} NMR spectra. The IR spectrum in Nujol shows
the characteristic ν(CdCdC) vibration band for this
type of ligands20 at 1909 cm-1, and the 13C{1H} NMR
spectrum exhibits resonances at 260.5, 227.2, and 150.7
4. Rea ction of 4 w ith 1,1-Dip h en yl-2-p r op yn -1-
ol a n d TlP F 6. Treatment of acetone solutions of 4 with
1.1 equiv of 1,1-diphenyl-2-propyn-1-ol and 1.0 equiv of
thallium hexafluorophosphate at 10 °C leads, after 45
min, to the hydride-hydroxyalkynyl-osmium(IV) com-
plex [OsH{η5-C5H4(CH2)2PPh2}{CtCC(OH)Ph2}(PiPr3)]-
PF6 (9), as a result of the extraction of the chloride
ligand from compound 4 and the oxidative addition of
(20) (a) Bruce, M. I. Chem. Rev. 1998, 98, 2797. (b) Cadierno, V.;
Gamasa, M. P.; Gimeno, J . Eur. J . Inorg. Chem. 2001, 571.

Os Complexes Containing a Cyclopentadienyl Ligand
Organometallics, Vol. 23, No. 12, 2004 3027
ppm, corresponding to the CR, Câ, and Cγ carbon atoms
of the allenylidene group, respectively. The 31P{1H}
NMR spectrum shows two doublets at 19.1 and 16.9
ppm, with a P-P coupling constant of 14 Hz.
Exploratory studies show that the reactivity of 10 is
similar to that of the related bis(triisopropylphosphine)
derivative [Os(η5-C5H5)(dCdCdCPh2)(PiPr3)2]PF6. Thus,
complex 10 is stable in the presence of alcohols and
amines. However it reacts with strong acids. The
addition of 1.0 equiv of HPF6‚H2O to diethyl ether
solutions of 10 affords the dicationic carbyne derivative
gain information about how the fact of tethering a
phosphorus group to a cyclopentadienyl ring influences
the chemistry of half-sandwich cyclopentadienyl-os-
mium compounds. We have proved that the CH2CH2
chain has a strong influence on the competitive alkane-
arene intramolecular C-H activation in mixed-ligand
alkylphosphine-arylphosphine compounds. Thus, while
the extraction of the chloride ligand from Os(η5-
C5H5)Cl(PiPr3)(PPh3) gives rise to the selective ortho-
C-H activation of one of the triphenylphosphine aryl
groups, the extraction of the chloride ligand from [Os-
[Os{η5-C5H4(CH2)2PPh2}(tCCHdCPh2)(PiPr3)](PF6)2 (11),
as result of the acid proton addition to the Câ carbon
atom of the allenylidene ligand in 10. The formation of
11 agrees well with EHT-MO calculations on transition
metal allenylidene compounds, which indicate a nucleo-
philic character of the allenylidene Câ carbon atom.10e,21
In addition, it should be mentioned that in contrast to
[Os(η5-C5H5)tCCHdCPh2)(PiPr3)2](PF6)2, complex 11
does not undergo the deprotonation of the alkenylcar-
bene ligand in diethyl ether. This indicates that the
alkenylcarbyne ligand at 11 is a weaker Bro¨nsted acid
than that of the cyclopentadienyl-bis(triisopropylphos-
phine) compound.10e
{η5-C5H4(CH2)2PPh2}Cl(PiPr3) causes the selective C-H
activation of one of the methyl groups of the triisopro-
pylphosphine ligand. The reason for this difference in
reactivity seems to be the greater strength of the Os-
PPh2 bond in the 2-diphenylphosphinoethylcyclopenta-
dienyl osmium complex with regard to that of the
triphenylphosphine derivative. The CH2CH2 chain pre-
vents the Os-PPh2 dissociation, which is crucial for the
activation of an aryl substituent.
Substitution of a triisopropylphosphine ligand and the
cyclopentadienyl ring by the 2-diphenylphosphinoeth-
ylcyclopentadienyl ligand also affects the stability of the
half-sandwich cyclopentadienyl-hydride-alkynyl-osmium-
(IV) compounds. In contrast to the bis(triisopropylphos-
phine) derivatives of the type [OsH(η5-C5H5)(CtCR)-
Complex 11 was isolated as an orange solid in 94%
yield. The presence of an alkenylcarbyne ligand in this
complex is supported by the 1H and 13C{1H} NMR
1
(PiPr3)2]PF6, complexes of formula [OsH{η5-C5H4(CH2)2P-
Ph2}(CtCR)(PiPr3)][PF6] (R ) Ph, C(OH)Ph2) are not
stable and evolve into the corresponding metal-cumu-
lene compounds. The lower stability of the correspond-
ing substituted cyclopentadienyl complexes seems to be
a consequence of the lower basicity of the intermediate
spectra. The H NMR spectrum shows a singlet at 6.01
ppm due to the alkenylcarbyne dCH proton. In the
13C{1H} NMR spectrum, the CR carbon atom of the
unsaturated η1-carbon ligand gives rise to a double
doublet at 297.0 ppm, with C-P coupling constants of
6 and 11 Hz. The Câ and Cγ carbon atoms display
singlets at 132.5 and 174.8 ppm, respectively. The
31P{1H} NMR spectrum shows two doublets at 25.7 and
22.3 ppm, with a P-P coupling constant of 7 Hz.
species [Os{η5-C5H4(CH2)2PPh2}(CtCR)(PiPr3), isolated
for
R
)
Ph, with regard to that of Os-
(η5-C5H5)(CtCR)(PiPr3)2.
In comparison with the corresponding bis(triisopro-
pylphosphine)cyclopentadienyl derivative, the presence
of the 2-diphenylphosphinoethylcyclopentadienyl system
also causes a decrease of the Bro¨nsted acid character
Con clu d in g Rem a r k s
This paper reveals that the unsaturated six-coordi-
nate complex OsH2Cl2(PiPr3)2 is a useful starting mate-
rial to obtain osmium compounds with a cyclopentadi-
enyl ligand bearing a pendant donor group. Thus, the
preparation and full characterization of the first os-
mium(IV) and osmium(II) derivatives with the 2-diphe-
nylphosphinoethylcyclopentadienyl ligand are reported.
Complex OsH2Cl2(PiPr3)2 reacts with Li[C5H4(CH2)2-
PPh2] to give the dihydride-osmium(IV) compound
of the [tCCHdCPh2]+ carbyne ligand. Thus, while [Os-
{η5-C5H4(CH2)2PPh2}(tCCHdCPh2)(PiPr3)](PF6)2 is
stable in diethyl ether, the analogous bis(triisopropy-
lphosphine) derivative undergoes a deprotonation reac-
tion in that solvent.
In conclusion, we have shown an entry into the
chemistry of osmium derivatives containing a cyclopen-
tadienyl ligand bearing a pendant donor function, as
well as some of the differences in reactivity between
2-diphenylphosphinoethylcyclopentadienyl complexes
and related cyclopentadienyl-phosphine-osmium deriva-
tives.
[OsH2{η5-C5H4(CH2)2PPh2}(PiPr3)]Cl, which can be trans-
formed into the chloro-osmium(II) derivative [Os{η5-
C5H4(CH2)2PPh2}Cl(PiPr3), by a two-step procedure
involving the deprotonation of the dihydride and the
subsequent chlorination of the resulting monohydride
complex. This chloro-osmium(II) species is a useful
compound to study the chemistry of the 2-diphenylphos-
phinoethylcyclopentadienyl-osmium complexes and to
Exp er im en ta l Section
Gen er a l In for m a tion . All manipulations were performed
at an argon/vacuum manifold using standard Schlenk tech-
niques. Solvents were dried by known procedures and used
(21) (a) Berke, H.; Huttner, G.; Von Seyerl, J . N. Naturforsch. 1981,
36B, 1277. (b) Cadierno, V.; Gamasa, M. P.; Gimeno, J .; Gonza´lez-
Cueva, M.; Lastra, E.; Borge, J .; Garc´ıa-Granda, S.; Pe´rez-Carren˜o,
E. Organometallics, 1996, 15, 2137. (c) Edwards, A. J .; Esteruelas, M.
A.; Lahoz, F. J .; Modrego, J .; Oro, L. A.; Schrickel, J . Organometallics
1996, 15, 3556. (d) Esteruelas, M. A.; Go´mez, A. V.; Lo´pez, A. M.;
Modrego, J .; On˜ate, E. Organometallics 1997, 16, 5826.
freshly distilled. OsH2Cl2(PiPr3)2 (1) and Li[C5H4(CH2)2-
22
PPh2]23 were prepared according to previous reports. Infrared
(22) Aracama, M.; Esteruelas, M. A.; Lahoz, F. J .; Lo´pez, J . A.;
Meyer, U.; Oro, L. A.; Werner, H. Inorg. Chem. 1991, 30, 288.

3028 Organometallics, Vol. 23, No. 12, 2004
Esteruelas et al.
spectra were recorded on a Nicolet 550 spectrometer as Nujol
mulls on polyethylene sheets. NMR spectra were recorded on
a Varian UNITY 300, Varian GEMINI 2000-300 MHz, or
Bruker ARX 300 spectrometer. 1H and 13C{1H} chemical shifts
are reported relative to tetramethylsilane, and those of 31P{1H}
relative to H3PO4 (85%). Coupling constants J are given in
hertz. C, H analyses were carried out in a Perkin-Elmer 2400
CHNS/O analyzer. FAB mass spectra analyses were performed
with a VG Auto Spec instrument. The ions were produced with
a standard Cs- gun at 30 kV using 3-nitrobenzyl alcohol (NBA)
as matrix.
stirred at room temperature for 12 h. The resulting orange
solution was concentrated to dryness. Addition of ca. 20 mL
of toluene and filtration resulted in a clear solution, from which
traces of derivative 2 formed during the process were removed
by precipitation with ca. 5 mL of pentane. The suspension was
filtered, the combined filtrate concentrated under reduced
pressure, and the resulting yellow solid washed with cold
pentane and dried under vacuum. Yield: 79% (1.0 g, 1.51
mmol). Anal. Calcd for C28ClH39OsP2: C, 50.70; H, 5.93.
Found: C, 50.68; H, 6.20. MS (FAB+): m/e 664 (M+), 627 (M+
- Cl). 1H NMR (300 MHz, C6D6 293 K): δ 8.46 (m, 2H, C6H5),
7.21 (m, 4H, C6H5), 6.92 (m, 4H, C6H5), 5.39, 4.91, 4.71, 4.08
(all m, each 1H, C5H4), 3.18, 2.59 (both m, each 1H, CH2CH2P),
2.05 (m, 3H, PCH), 1.37 (m, 2H, CH2CH2P), 1.15 (dd, 9H,
J (HH) ) 7.2, J (PH) ) 13.8, PCCH3), 0.79 (dd, 9H, J (HH) )
7.2, J (PH) ) 11.4, PCCH3). 31P{1H} NMR (121.4 MHz, C6D6,
293 K): δ 11.4, 7.4 (both d, J (PP′) ) 13). 13C{1H} NMR (75.4
MHz, C6D6, 293 K, plus APT, plus HMQC): δ 141.9 (-, d,
J (PC) ) 32, ipso-C6H5), 141.8 (-, d, J (PC) ) 32, ipso-C6H5),
136.3, 132.6 (+, both d, J (PC) ) 10, C6H5), 129.9, 129.0, 127.8
(+, all m, C6H5), 105.2 (-, d, J (PC) ) 6, ipso-C5H4), 86.3 (+, d,
J (PC) ) 7, C5H4), 75.3 (+, d, J (PC) ) 8, C5H4), 70.2 (+, d, J (PC)
) 11, C5H4), 57.6 (-, d, J (PC) ) 40, -CH2CH2P), 26.1 (+, d,
J (PC) ) 24, PCH), 21.6 (+, s, PCCH3), 20.8 (-, s, -CH2CH2P),
19.7 (+, s, PCCH3).
P r ep a r a t ion of [OsH 2{η5-C5H 4(CH 2)2P P h 2}(P iP r 3)]Cl
(2). To a suspension of Li[C5H4(CH2)2PPh2] (0.54 g, 1.90 mmol)
and 1 (1.0 g, 1.71 mmol) in 20 mL of toluene was added PiPr3
(0.10 mL, 0.52 mmol). Stirring of the reaction mixture for 12
h at room temperature gave a yellow solution and a white
precipitate. The solvent was removed under vacuum, and
dichloromethane (3 × 5 mL) was then added to the solid
residue. The resulting suspension was filtered to separate the
LiCl precipitate and the combined filtrate concentrated under
reduced pressure. The solid residue was washed with toluene
(1 × 5 mL) and pentane (1 × 5 mL) and dried under vacuum
to give a white powder. Yield: 64% (0.73 g, 1.10 mmol). Anal.
Calcd for C28ClH41OsP2: C, 50.55; H, 6.41. Found: C, 50.39;
H, 6.44. IR (Nujol): ν(Os-H) 2133 cm-1. MS (FAB+): m/e 630
(M+). 1H NMR (300 MHz, CD2Cl2, 293 K): δ 7.72-7.65 (m,
4H, PPh2), 7.50-7.47 (m, 6H, PPh2), 6.06, 5.45 (both m, each
2H, C5H4), 3.85 (m, 2H, CH2CH2P), 2.19, 2.09 (both m, each
1H, CH2CH2P), 1.67 (m, 3H, PCH), 0.95 (dd, 9H, J (HH) ) 7.2,
J (PH) ) 15.0, PCCH3), -13.10 (dd, 2H, J (P′H) ) 25.5, J (PH)
) 30.9, Os-H). 31P{1H} NMR (121.4 MHz, CD2Cl2, 293 K): δ
44.7, 30.1 (both d, J (PP′) ) 30). 13C{1H} NMR (75.4 MHz,
CD2Cl2, 293 K, plus APT): δ 133.3 (-, d, J (PC) ) 46, ipso-
C6H5), 132.9 (+, d, J (PC) ) 11, C6H5), 131.7 (+, d, J (PC) ) 2,
C6H5), 129.0 (+, d, J (PC) ) 11, C6H5), 119.9 (-, dd, J (PC) ) 4,
J (P′C) ) 9, ipso-C5H4), 85.3 (+, s, C5H4), 78.9 (+, d, J (PC) )
4, C5H4), 59.3 (-, d, J (PC) ) 38, -CH2CH2P), 29.7 (+, d, J (PC)
) 33, PCH), 20.6 (-, s, -CH2CH2P), 19.6 (+, s, PCCH3).
P r epar ation of [{CH2CH(CH3)iP r 2}OsH{η5-C5H4(CH2)2P -
P h 2}]P F 6 (5). Acetone (10 mL) was added to a dry mixture of
4 (0.25 g, 0.37 mmol) and TlPF6 (0.13 g, 0.38 mmol). Stirring
of the reaction mixture at room temperature for 3 h afforded
an orange solution and a white precipitate. The suspension
was filtered, the filtrate concentrated under reduced pressure,
and the resulting yellow solid washed with cold pentane and
dried under vacuum. Complex 5 was obtained as a 1:1 mixture
of stereoisomers. Yield: 94% (0.27 g, 0.35 mmol). Anal. Calcd
for C28F6H39OsP3: C, 43.52; H, 5.09. Found: C, 43.32; H, 5.00.
IR (Nujol): ν(Os-H) 2120 cm-1, ν(PF6) 839 cm-1. 1H NMR (300
MHz, (CD3)2CO, 293 K, plus 1H{31P}): δ 8.21-8.14 (m, 4H,
C6H5), 7.73-7.50 (m, 16H, C6H5), 6.18, 6.13, 6.03, 6.02, 6.00,
5.97, 5.88, 5.83 (all m, each 1H, C5H4), 4.10-3.70 (m, 4H), 3.45
(m, 1H), 3.11 (ddd, 1H, J 2(HH) ) J 3(HH) ) 9.3, J (PH) ) 29.7,
Os-CH2), 2.69-2.36 (m, 7H), 2.05-1.94 (m, 6H), 1.40-1.16
(m, 25H, PCCH3 + Os-CH2), 0.89 (ddd, 3H, J 3(HH) ) 15.4,
J 4(HH) ) 7.0, J (PH) ) 15.9, PCH(CH3)-CH2), 0.44 (ddd, 1H,
J 2(HH) ) 9.3, J 3(HH) ) 6.8, J (PH) ) 15.8, Os-CH2), -12.38
(dd, 1H, J (PH) ) 31.2, J (P′H) ) 25.8, Os-H), -12.84 (dd, 1H,
J (PH) ) 29.7, J (P′H) ) 25.2, Os-H). 31P{1H} NMR (121.4
MHz, (CD3)2CO, 293 K): δ 33.0, -17.3 (both d, J (PP′) ) 31),
δ 31.3, -11.1 (both d, J (PP′) ) 25), -139.8 (sept, J (PF) ) 712).
19F{1H} NMR (282.3 MHz, (CD3)2CO, 293 K): δ -73.0 (d, J (PF)
) 712). 13C{1H} NMR (75.4 MHz, (CD3)2CO, 293 K, plus APT
plus HETCOR): δ 134.4 (+, d, J (PC) ) 11, C6H5), 132.4, 132.3
(+, both d, J (PC) ) 8, C6H5), 132. 3, 131.8 (-, both d, J (PC) )
38, ipso-C6H5), 131.9 (+, m, C6H5), 131.3, 131.2 (+, both d,
J (PC) ) 3, C6H5), 129.4 (-, d, J (PC) ) 52, ipso-C6H5), 129.1
(+, d, J (PC) ) 10, C6H5), 129.0 (+, d, J (PC) ) 10, C6H5), 128.8
(+, d, J (PC) ) 10, C6H5), 128.7 (+, d, J (PC) ) 10, C6H5), 128.6
(-, d, J (PC) ) 68, ipso-C6H5), 128.6 (+, d, J (PC) ) 10, C6H5),
122.8 (-, dd, J (PC) ) 9, J (P′C) ) 4, ipso-C5H4), 122.6 (-, dd,
J (PC) ) 9, J (P′C) ) 4, ipso-C5H4), 90.6 (+, d, J (PC) ) 4, C5H4),
89.9 (+, d, J (PC) ) 2, C5H4), 83.4, 83.2 (+, both s, C5H4), 81.5
(+, d, J (PC) ) 7, C5H4), 78.5 (+, d, J (PC) ) 7, C5H4), 75.7,
75.5 (+, both d, J (PC) ) 5, C5H4), 56.2, (-, d, J (PC) ) 37,
-CH2CH2P), 55.2 (-, d, J (PC) ) 37, -CH2CH2P), 46.6 (+, dd,
P r ep a r a tion of [OsH{η5-C5H4(CH2)2P P h 2}(P iP r 3) (3). To
a solution of 2 (1.40 g, 2.10 mmol) in 20 mL of tetrahydrofuran
was added a 0.19 M solution of KOH in methanol (13.3 mL,
2.52 mmol). The reaction mixture was stirred for 12 h at room
temperature. The solvent was removed under reduced pressure
and the residue extracted with pentane (3 × 10 mL). The
combined filtrate was concentrated to dryness and the result-
ing yellow oil washed with cold propan-2-ol and dried under
vacuum. Yield: 98% (1.30 g, 2.06 mmol). MS (FAB+): m/e 629
(M+). 1H NMR (300 MHz, C6D6, 293 K): δ 8.30 (m, 2H, p-C6H5),
7.33-6.97 (m, 8H, o-, m-C6H5), 4.93, 4.82, 4.79, 4.61 (all m,
each 1H, C5H4), 3.08 (m, 2H, CH2CH2P), 1.84, 1.69 (both m,
each 1H, CH2CH2P), 1.51 (m, 3H, PCH), 1.01 (dd, 9H, J (HH)
) 7.2, J (PH) ) 13.2, PCCH3), 0.88 (dd, 9H, J (HH) ) 7.2, J (PH)
) 15.9, PCCH3), -14.40 (dd, 1H, J (PH) ) 21.6, J (P′H) ) 32.7,
Os-H). 31P{1H} NMR (121.4 MHz, C6D6, 293 K): δ 41.7, 27.9
(both d, J (PP′) ) 5). 13C{1H} NMR (75.4 MHz, C6D6, 293 K,
plus APT): δ 143.2 (-, d, J (PC) ) 32, ipso-C6H5), 140.5 (-, d,
J (PC) ) 38, ipso-C6H5), 136.0 (+, m, C6H5), 132.1 (+, d, J (PC)
) 9, C6H5), 129.5, 128.2 (+, both s, C6H5), 127.7 (+, d, J (PC)
) 9, C6H5), 127.5 (+, d, J (PC) ) 8, C6H5), 108.0 (-, dd, J (PC)
) J (P′C) ) 5, ipso-C5H4), 78.1 (+, d, J (PC) ) 6, C5H4), 67.8
(+, s, C5H4), 67.7 (+, s, C5H4), 65.4 (+, d, J (PC) ) 8, C5H4),
58.0 (-, d, J (PC) ) 35, -CH2CH2P), 29.3 (+, d, J (PC) ) 25,
PCH), 22.4 (-, d, J (PC) ) 4, -CH2CH2P), 21.4, 20.2 (+, both
s, PCCH3).
i
i
J (PC) ) 34, J (P′C) ) 3, Pr2PCH), 43.4 (+, d, J (PC) ) 36, -
Pr2PCH), 29.4 (+, d, J (PC) ) 26, PCH(CH3)2), 26.5 (+, d, J (PC)
) 19, PCH(CH3)2), 25.6 (+, d, J (PC) ) 22, PCH(CH3)2), 23.9
(+, s, iPr2PCHCH3), 23.8 (+, s, iPr2PCHCH3), 23.6 (+, d, J (PC)
) 17, PCH(CH3)2), 21.1, 20.5 (+, both s, PCHCH3), 20.1 (-, s,
-CH2CH2P), 20.0 (+, s, PCHCH3), 19.9 (-, s, -CH2CH2P), 19.8
(+, s, PCHCH3), 19.3 (+, d, J (PC) ) 2, PCHCH3), 19.1 (+, d,
P r ep a r a tion of [Os{η5-C5H4(CH2)2P P h 2}Cl(P iP r 3) (4). A
solution of 3 (1.20 g, 1.91 mmol) in 20 mL of chloroform was
(23) Kettenbach, R. T.; Bonrath, W.; Butenscho¨n, H. Chem. Ber.
1993, 126, 1657.

Os Complexes Containing a Cyclopentadienyl Ligand
Organometallics, Vol. 23, No. 12, 2004 3029
J (PC) ) 5, PCHCH3), -22.5 (-, dd, J (PC) ) 39, J (P′C) ) 7,
Os-CH2-), -24.3 (-, dd, J (PC) ) 37, J (P′C) ) 8, Os-CH2).
Reaction of 4 with P h en ylacetylen e an d TlP F 6: P r epa-
concentrated under reduced pressure and the pale yellow solid
washed with cold pentane (2 × 5 mL) and dried under vacuum.
Yield: 88% (0.11 g, 0.15 mmol). Anal. Calcd for C36H44OsP2:
C, 59.35; H, 6.04. Found: C, 59.14; H, 5.99. MS (FAB+): m/e
r a tion of [Os{η5-C5H4(CH2)2P P h 2}(dCdCHP h )(P iP r 3)]P F 6
(7). A solution of 4 (0.80 g, 1.2 mmol) and phenylacetylene
(0.14 mL, 1.3 mmol) in 10 mL of acetone was treated with
TlPF6 (0.42 g, 1.2 mmol) at -20 °C. After stirring of the
mixture for 1 h at the same temperature, the suspension was
filtered. NMR spectra of an aliquot of the pale yellow solution
showed the presence of compounds 6 and 7 in ca. 8:2 molar
731 (M+), m/e 569 (M+ - PiPr3). IR (Nujol): ν(CtC) 2059 cm-1
.
1H NMR (300 MHz, C6D6, 273 K): δ 8.60 (dd, 2H, J (HH) )
8.1, J (HH) ) 9.6, C6H5), 7.63 (d, 2H, J (HH) ) 8.1, C6H5), 7.25
(m, 5H, C6H5), 7.16 (m, 2H, C6H5), 6.92 (m, 4H, C6H5), 5.27,
4.83, 4.66, 4.43 (all m, each 1H, C5H4), 3.09, 2.76 (both m, each
1H, PCH2CH2), 2.00 (m, 3H, PCH), 1.55, 1.43 (both m, each
1H, PCH2CH2), 1.15 (dd, 9H, J (HH) ) 6.9, J (PH) ) 13.5,
PCCH3), 0.80 (dd, 9H, J (HH) ) 7.2, J (PH) ) 11.7, PCCH3).
31P{1H} NMR (121.4 MHz, C6D6, 273 K): δ 17.2, 9.3 (both d,
J (PP′) ) 11). 13C{1H} NMR (100 MHz, (C6D6, 273 K, plus
APT): δ 141.1 (-, d, J (PC) ) 34, ipso-PC6H5), 139.9 (-, d,
J (PC) ) 37, ipso-PC6H5), 135.8 (+, d, J (PC) ) 10, PC6H5), 132.2
(+, d, J (PC) ) 9, PC6H5), 131.4 (+, s, C6H5), 129.6 (+, d, J (PC)
) 2, PC6H5), 128.6 (+, d, J (PC) ) 2, PC6H5), 128.2 (+, s, C6H5),
127.7 (+, d, J (PC) ) 9, PC6H5), 127.3 (+, d, J (PC) ) 8, PC6H5),
123.0 (+, s, C6H5), 113.1 (-, dd, J (PC) ) 2, J (P′C) ) 6, ipso-
C5H4), 110.7 (-, br, tCC6H5), 94.5 (-, br, Os-Ct), 78.5, 78.1
(+, both d, both J (PC) ) 7, C5H4), 72.1 (+, d, J (PC) ) 10, C5H4),
65.9 (+, s, C5H4), 57.5 (-, d, J (PC) ) 48, PCH2CH2), 26.8 (+,
d, J (PC) ) 26, PCH), 21.6 (+, s, PCCH3), 20.4 (-, d, J (PC) )
3, PCH2CH2), 19.5 (+, d, J (PC) ) 2, PCCH3).
ratio. Spectroscopic data for [OsH{η5-C5H4(CH2)2PPh2}
(CtCPh)(PiPr3)]PF6, 6: 1H NMR (300 MHz, (CD3)2CO, 273
K): δ 8.05 (m, 2H, C6H5), 7.74-7.08 (m, 13H, C6H5), 6.35, 6.24,
6.14, 5.83 (all m, each 1H, C5H4), 4.26, 4.07 (both m, each 1H,
-CH2CH2P), 2.60 (m, 3H, PCH), 2.45, 2.10 (both m, each 1H,
-CH2CH2P), 1.14 (dd, 9H, J (HH) ) 6.9, J (PH) ) 15, PCCH3),
1.03 (dd, 9H, J (HH) ) 8.7, J (PH) ) 15, PCCH3), -12.35 (dd,
1H, J (PH) ) 36.9, J (P′H) ) 26.4, Os-H). 31P{1H} NMR (121.4
MHz, (CD3)2CO, 273 K): δ 23.2, 13.5 (d, J (PP′) ) 35), -144.3
(sept, J (PF) ) 708). 13C{1H} NMR (75.4 MHz, (CD3)2CO, 253
K, plus APT): δ 134.3 (+, d, J (PC) ) 10, PC6H5), 134.0 (+, d,
J (PC) ) 8, PC6H5), 132.1 (+, d, J (PC) ) 3, PC6H5), 131.2 (+,
s, C6H5), 131.1 (-, d, J (PC) ) 67, ipso-PC6H5), 130.3 (-, d,
J (PC) ) 55, ipso-PC6H5), 129.3 (+, d, J (PC) ) 10, PC6H5), 128.2
(+, s, C6H5), 127.9 (+, d, J (PC) ) 11, PC6H5), 127.7 (-, s, ipso-
C6H5), 126.1 (+, s, C6H5), 123.4 (-, dd, J (PC) ) 4, J (P′C) ) 9,
ipso-C5H4), 115.4 (-, br, tCC6H5), 97.9, 84.3 (+, s, C5H4), 83.8
(+, d, J (PC) ) 6, C5H4), 79.4 (+, s, C5H4), 65.6 (-, dd, J (PC) )
J (P′C) ) 25, Os-Ct), 57.7 (-, d, J (PC) ) 40, -CH2CH2P),
28.0 (+, d, J (PC) ) 32, PCH), 19.7 (+, s, PCCH3), 18.9 (-, s,
CH2CH2P), 18.8 (+, s, PCCH3).
Rea ction of 4 w ith 1,1-Dip h en yl-2-p r op yn -1-ol a n d
TlP F 6: P r ep a r a tion of [Os{η5-C5H4(CH2)2P P h 2}(dCdCd
CP h 2)(P iP r 3)]P F 6 (10). A solution of 4 (0.60 g, 0.90 mmol)
and 1,1-diphenyl-2-propyn-1-ol (0.23 g, 1.1 mmol) in 10 mL of
acetone was reacted with TlPF6 (0.31 g, 0.90 mmol) at 10 °C.
After stirring of the mixture for 45 min at that temperature,
the suspension was filtered. NMR spectra of an aliquot of the
resulting orange solution showed the presence of compounds
The solution was warmed to room temperature and periodi-
cally monitored by 1H and 31P{1H} NMR spectroscopy. After
12 h at room temperature, only complex 7 was observed. The
light red solution was concentrated under reduced pressure
and the resulting red solid washed with cold pentane (3 × 5
mL) and dried under vacuum. Yield: 82% (0.86 g, 0.98 mmol).
Anal. Calcd for C36H45OsP3F6: C, 49.42; H, 5.18. Found: C,
49.60; H, 4.99. IR (Nujol): ν(CdC) 1623, 1592 cm-1, ν(PF6) 838
cm-1. MS (FAB+): m/e 729 (M+). 1H NMR (300 MHz, (CD3)2CO,
9 and 10 in ca. 9:1 molar ratio. Spectroscopic data for [OsH-
{η5-C5H4(CH2)2PPh2}{CtCC(OH)Ph2}(PiPr3)]PF6, 9: 1H NMR
(300 MHz, CD2Cl2, 283 K): δ 7.79 (m, 2H, C6H5), 7.60 (m, 7H,
C6H5), 7.56-7.18 (m, 11H, C6H5), 6.03, 6.02, 5.79, 5.43 (all m,
each 1H, C5H4), 3.96, 3.81 (both m, each 1H, PCH2CH2), 2.96
(br, 1H, OH), 2.49 (m, 1H, PCH2CH2), 2.31 (m, 3H, PCH), 2.03
(m, 1H, PCH2CH2), 0.95 (dd, 9H, J (HH) ) 7.1, J (PH) ) 15.3,
PCCH3), 0.85 (dd, 9H, J (HH) ) 7.0, J (PH) ) 14.2, PCCH3),
-12.54 (dd, 1H, J (PH) ) 37.2, J (P′H) ) 26.7, Os-H). 31P{1H}
NMR (121.4 MHz, CD2Cl2, 283 K): δ 25.6, 13.9 (d, J (PP′) )
34), -144.2 (sept, J (PF) ) 708). 13C{1H} NMR (75.4 MHz,
CD2Cl2, 253 K, plus APT): δ 146.6 (-, d, J (PC) ) 61, ipso-
PC6H5), 133.9 (+, d, J (PC) ) 8, PC6H5), 133.7 (+, d, J (PC) )
10, PC6H5), 132.2, 131.5 (+, both d, J (PC) ) 2, PC6H5), 130.6
(-, d, J (PC) ) 58, ipso-PC6H5), 130.1 (-, s, ipso-C6H5), 129.4
(+, d, J (PC) ) 10, PC6H5), 128.3, 127.9 (+, s, CC6H5), 127.8
(+, d, J (PC) ) 11, PC6H5), 126.9, 126.4, 125.7 (+, all s, CC6H5),
122.6 (-, dd, J (PC) ) 4, J (PC) ) 9, ipso-C5H4), 116.0 (-, dd,
J (PC) ) 3 ) J (P′C), Os-CtC), 97.8, 83.6 (+, both s, C5H4),
82.7 (+, d, J (PC) ) 6, C5H4), 78.7 (+, s, C5H4), 75.1 (-, s, CPh2),
60.3 (-, dd, J (PC) ) J (P′C) ) 24, Os-Ct), 56.2 (-, d, J (PC)
) 39, PCH2CH2), 27.9 (+, d, J (PC) ) 32, PCH), 19.8 (+, s,
PCCH3), 18.8 (-, s, PCH2CH2), 18.7 (+, s, PCCH3).
1
293 K, plus H{31P} plus COSY): δ 8.01-7.94 (m, 2H, C6H5),
7.70-7.38 (m, 8H, C6H5), 7.30-7.25 (m, 2H, C6H5), 7.08-7.02
(m, 3H, C6H5), 6.49 (m, 1H, C5H4), 6.14, (m, 2H, C5H4), 6.08
(m, 1H, C5H4), 3.98, 3.87 (both m, each 1H, PCH2CH2), 3.43
(d, 1H, J (PH) ) 3.0, OsdCdCH), 2.70 (m, 1H, PCH2CH2), 2.13
(m, 3H, PCH), 1.94 (m, 1H, PCH2CH2), 1.22 (dd, 9H, J (HH) )
7.2, J (PH) ) 14.8, PCCH3), 1.11 (dd, 9H, J (HH) ) 7.2, J (PH)
) 13.4, PCCH3). 31P{1H} NMR (121.4 MHz, CD2Cl2, 293 K): δ
20.7, 15.9 (both d, J (PP′) ) 12), -144.2 (sept, J (PF) ) 714).
19F{1H} NMR (282.3 MHz, CD2Cl2, 293 K): δ -73.0 (d, J (PF)
) 714). 13C{1H} NMR (75.4 MHz, (CD3)2CO, 293 K, plus
APT): δ 309.5 (-, dd, J (PC) ) 6, J (P′C) ) 13, OsdC), 132.9
(-, d, J (PC) ) 49, ipso-PC6H5), 132.3 (-, d, J (PC) ) 59, ipso-
PC6H5), 131.1 (+, d, J (PC) ) 9, PC6H5), 130.6 (+, d, J (PC) )
2.8, PC6H5), 130.4 (+, d, J (PC) ) 2.4, PC6H5), 128.5 (-, d, J (PC)
) 10, ipso-C5H4), 127.7 (+, d, J (PC) ) 13, PC6H5), 127.5 (+, d,
J (PC) ) 14, PC6H5), 127.0, 125.4 (+, both s, dCC6H5), 125.3
(-, s, ipso-C6H5), 124.4 (+, s, dCC6H5), 115.2 (+, s, dCH), 86.0
(+, d, J (PC) ) 7, C5H4), 85.2 (+, d, J (PC) ) 5, C5H4), 83.1 (+,
d, J (PC) ) 3, C5H4), 76.9 (+, s, C5H4), 52.5 (-, d, J (PC) ) 37,
PCH2CH2), 27.1 (+, d, J (PC) ) 29, PCH), 18.7 (+, s, PCCH3),
18.0 (-, s, PCH2CH2), 17.8(+, s, PCCH3).
The solution was warmed to room temperature, and the
1
reaction was periodically monitored by H and 31P{1H} NMR
spectroscopy. After 12 h at room temperature, only complex
10 was observed. The dark yellow solution was concentrated
under reduced pressure and the resulting very dark yellow
solid washed with cold diethyl ether and pentane (3 × 5 mL)
and dried under vacuum. Yield: 88% (0.76 g, 0.79 mmol). Anal.
Calcd for C43H49OsP3F6: C, 53.65; H, 5.09. Found: C, 53.40;
P r epar ation of [Os{η5-C5H4(CH2)2P P h 2}(CtCP h )(P iP r 3)
(8). To a solution of 7 (0.15 g, 0.17 mmol) in 5 mL of
tetrahydrofuran was added a 0.19 M solution of KOH in MeOH
(1.0 mL, 0.19 mmol). Stirring of the mixture for 6 h at room
temperature afforded a pale yellow suspension. Solvents were
evaporated to dryness, and the resulting solid residue was
extracted with toluene (2 × 5 mL). The combined filtrate was
H, 4.98. IR (Nujol): ν (CdCdC) 1909 cm-1, ν (PF6) 838 cm-1
.
MS (FAB+): m/e 819 (M+), 659 (M+ - PiPr3). 1H NMR (300
MHz (CD3)2CO, 293 K): δ 7.95 (m, 4H, C6H5), 7.89-7.74 (m,
4H, C6H5), 7.65 (m, 4H, C6H5), 7.52 (m, 4H, C6H5), 7.46-7.35
(m, 4H, C6H5), 6.60, 6.51, 6.07, 5.97 (all m, each 1H, C5H4),

3030 Organometallics, Vol. 23, No. 12, 2004
Esteruelas et al.
Ta ble 3. Cr ysta l Da ta a n d Da ta Collection a n d
Refin em en t for 2 a n d 4
3.98, 3.78 (both m, each 1H, PCH2CH2), 2.69-2.43 (m, 1H,
PCH2CH2), 2.14 (m, 3H, PCH), 1.84 (m, 1H, PCH2CH2), 1.16
(dd, 9H, J (HH) ) 7.2, J (PH) ) 14.7, PCCH3), 1.11 (dd, 9H,
J (HH) ) 6.9, J (PH) ) 13.5, PCCH3). 31P{1H} NMR (121.4 MHz,
CD2Cl2, 293 K): δ 19.1, 16.9 (both d, J (PP′) ) 14), -144.9 (sept,
J (PF) ) 734). 19F{1H} NMR (282.3 MHz, CD2Cl2, 293 K): δ
-69.3 (d, J (PF) ) 734). 13C{1H} NMR (75.4 MHz, CD2Cl2, 293
K, plus APT): δ 260.5 (-, br, OsdC), 227.2 (-, br, dCd) 150.7
(-, d, J (PC) ) 1, dCPh2), 149.4 (-, s, ipso-C6H5), 134.6 (-, d,
J (PC) ) 45, ipso-PC6H5), 134.1 (-, d, J (PC) ) 31, ipso-PC6H5),
134.5 (+, d, J (PC) ) 11, PC6H5), 132.4 (+, d, J (PC) ) 9, PC6H5),
131.7 (+, d, J (PC) ) 3, PC6H5), 131.5 (+, d, J (PC) ) 2, PC6H5),
130.4, 129.6, 128.9 (+, s, C6H5), 128.8 (+, d, J (PC) ) 8, PC6H5),
128.7 (+, d, J (PC) ) 11, PC6H5), 125.4 (-, dd, J (PC) ) 3, J (P′C)
) 8, ipso-C5H4), 87.5 (+, d, J (PC) ) 6, C5H4), 86.5 (+, d, J (PC)
) 5, C5H4), 85.4 (+, d, J (PC) ) 5, C5H4), 77.6 (+, s, C5H4), 55.0
(-, d, J (PC) ) 23, PCH2CH2), 29.5 (+, d, J (PC) ) 29, PCH),
20.5 (+, s, PCCH3), 19.8 (-, s, PCH2CH2), 19.5 (+, d, J (PC) )
2, PCCH3).
2
4
Crystal Data
formula
molecular wt
color and habit
symmetry, space triclinic, P1h
group
C
28H41ClOsP2O0.50
H
C28H39ClOsP2C3.5H4
709.25
light yellow, block
triclinic, P1h
674.21
light yellow, block
a, Å
b, Å
c, Å
12.3939(11)
13.5863(13)
17.2113(16)
98.701(2)
104.801(2)
91.190(2)
2764.4(4)
4
10.987(2)
15.170(3)
18.254(4)
88.250(3)
76.352(3)
80.402(3)
2915.1(10)
4
R, deg
â, deg
γ, deg
V, Å3
Z
D
calc, g cm-3
1.620
1.616
Data Collection and Refinement
Bruker Smart APEX
0.71073
diffractometer
λ(Mo KR)
P r ep a r a tion of [Os{η5-C5H4(CH2)2P P h 2}(tCCHdCP h 2)-
(P iP r 3)](P F 6)2 (11). A suspension of 10 (0.30 g, 0.31 mmol) in
5 mL of diethyl ether was treated with HPF6‚H2O (27.5 µL,
0.31 mmol) at room temperature. Stirring of the mixture for
1 h afforded an orange solid, which was isolated by filtration,
washed with diethyl ether and pentane (3 × 5 mL), and dried
under vacuum. Yield: 94% (0.32 g, 0.29 mmol). Anal. Calcd
for C43H50OsP4F12: C, 46.59; H, 4.51. Found: C, 46.34; H, 4.35.
monochromator
scan type
graphite oriented
ω scans
µ, mm-1
4.842
3, 56
100
4.595
3, 56
100
2θ, range deg
temp, K
no. of data
collected
33 425
34 982
no. of unique data 12 776 (Rint ) 0.0610) 13 397 (Rint ) 0.0366)
MS (FAB+): m/e 820 (M+). IR (Nujol): ν(CdC) 1511 cm-1
,
no. of params/
restraints
619/3
653/0
ν(PF6) 838 cm-1. 1H NMR (300 MHz, CD2Cl2, 293 K): δ 7.79-
7.62 (m, 15H, C6H5), 7.45 (m, 3H, C6H5), 7.33 (m, 2H, C6H5),
6.52, 6.40 (both m, each 1H, C5H4), 6.01 (s, 1H, dCH), 5.89,
5.36 (both m, each 1H, C5H4), 4.13, 3.63 (both m, each 1H,
PCH2CH2) 2.95, 2.16 (both m, each 1H, PCH2CH2), 1.93 (m,
3H, PCH), 1.05 (dd, 9H, J (HH) ) 7.2, J (PH) ) 14.7, PCCH3),
1.03 (dd, 9H, J (HH) ) 9.0, J (PH) ) 16.5, PCCH3). 31P{1H}
NMR (121.4 MHz, CD2Cl2, 293 K): δ 25.7, 22.3 (both d, J (PP′)
) 7), -144.9 (sept, J (PF) ) 716). 19F{1H} NMR (282.3 MHz,
CD2Cl2, 293 K): δ -72.1 (d, J (PF) ) 716). 13C{1H} NMR (100
MHz, CD2Cl2, 293 K, plus APT plus HMQC): δ 297.0 (-, dd,
J (PC) ) 6, J (P′C) ) 11, OstC), 174.8 (-, s, dCPh2), 135.3 (+,
s, C6H5), 134.8 (+, d, J (PC) ) 14, PC6H5), 134.5 (+, d, J (PC) )
4, PC6H5), 134.0 (+, d, J (PC) ) 4, PC6H5), 133.7 (+, s, C6H5),
133.1 (+, d, J (PC) ) 12, PC6H5), 132.5 (+, s, dCH), 131.2,
130.6, 130.4, 130.3, 130.2 (+, all s, C6H5), 97.1, 91.1 (+, br,
C5H4), 88.9 (+, d, J (PC) ) 2, C5H4), 83.7 (+, d, J (PC) ) 1, C5H4),
53.6 (-, obscured by CD2Cl2, PCH2CH2), 30.6 (+, d, J (PC) )
37, PCH), 20.4 (+, s, PCCH3), 19.4 (-, s, PCH2CH2), 19.5 (+,
d, J (PC) ) 4, PCCH3).
R1a [F2 > 2σ(F2)]
wR2b [all data]
Sc [all data]
0.0391
0.0761
0.860
0.0303
0.0566
0.861
a
b
2
R1(F) ) ∑|Fo| - |Fc|/∑|Fo|. wR2(F2) ) {∑[w(Fo - Fc2)2]/
∑[w(Fo2)2]}1/2
.
c Goof ) S ) {∑[Fo - Fc2)2]/(n - p)}1/2, where n is
2
the number of reflections and p is the number of refined param-
eters.
gram.24 Lorentz and polarization corrections were also per-
formed. The structures were solved by Patterson and Fourier
methods and refined by full matrix least-squares using the
2
Bruker SHELXTL program package25 minimizing w(Fo
-
Fc2)2. A molecule of water (2) and toluene (4) were observed in
the refinement. The hydride ligands of 2 were observed and
refined as free isotropic atoms with the same thermal param-
eter. Weighted R factors (Rw) and goodness of fit (S) are based
on F2; conventional R factors are based on F. Crystal data and
details of the data collection and refinement are given in Table
3.
X-r a y An a lysis of 2 a n d 4. Crystals suitable for X-ray
diffraction were grown from toluene (2) and pentane (4)
solutions cooled at -30 °C. Two irregular crystals of size 0.16
× 0.12 × 0.06 mm (2) and 0.28 × 0.06 × 0.04 mm (4) were
mounted on a Bruker Smart APEX CCD diffractometer at
100.0(2) K equipped with a normal focus, 2.4 kW sealed tube
source (molybdenum radiation, λ ) 0.71073 Å) operating at
50 kV and 40 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 7013 (2) or 959
(4) 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 pro-
Ack n ow led gm en t . Financial support from the
MCYT of Spain (Proyects BQU2002-00606 and PPQ2000-
0488-P4-02) is acknowledged. E.R. thanks CSIC and the
European Social Fund for funding through the I3P
Program.
Su p p or tin g In for m a tion Ava ila ble: 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.
OM049904+
(24) Blessing, R. H. Acta Crystallogr., Sect. A 1995, 51, 33.
(25) SHELXTL Package v.6.1.; Bruker-AXS: Madison, WI, 2000.