Synthesis and reactivity of Pt(II) complexes containing the orthometallated ligand [C6H4-2-PPh2C(H)COCH2PPh3]

Article abstract of DOI:10.1039/b002848g

The reaction of PtCl₂(NCPh)₂ with the ylide [Ph₃P=C(H)COCH₂PPh₃]ClO₄ (1:1 molar ratio, refluxing CHCl₃) affords trans-[PtCl₂(NCPh){C(H)PPh₃C(O)CH₂PPh₃}]ClO₄ 1. However, the reaction of PtCl₂(CH₂Cl₂, r.t.) or PtCl₂(NCMe)₂ (2-methoxyethanol, reflux) with the ylide [Ph₃P=C(H)COCH₂PPh₃]ClO₄ (1:1 molar ratio) affords the orthometallated [Pt{C₆H₄-2-PPh₂C(H)COCH₂PPh₃}(μ-Cl)]₂(ClO₄)₂, 2, as a mixture of diastereoisomers 2a-d. Treatment of 2 with PPh₃ (1:2 molar ratio) affords [PtCl{C₆H₄-2-PPh₂C(H)COCH₂PPh₃}(PPh₃)](ClO₄), 3, as a single geometric isomer. The reaction of 2 with AgClO₄ (1:2 molar ratio) in NCMe gives the solvato complex [Pt{C₆H₄-2-PPh₂C(H)COCH₂PPh₃}(NCMe)₂](ClO₄)₂, 4, while the reaction of 2 with Tl(acac) (1:2 molar ratio) gives [Pt{C₆H₄-2-PPh₂C(H)COCH₂PPh₃}(acac)](ClO₄), 5. The dicationic complexes [Pt{C₆H₄-2-PPh₂C(H)COCH₂PPh₃}(dppe)](ClO₄)₂, 6, and [Pt{C₆H₄-2-PPh₂C(H)COCH₂PPh₃}(phen)](ClO₄)₂, 7, can be obtained by reaction of 2 with AgClO₄ followed by addition of the appropiate ligand (1:2:2 molar ratio). The reaction of 6 with NaH gives [Pt{C₆H₄-2-PPh₂C(H)COCH=PPh₃}(dppe)](ClO₄), 8, while the reaction of 4 with PPh₃ and NaH gives [Pt{C₆H₄-2-PPh₂C(H)COCH=PPh₃}(PPh₃)₂](ClO₄), 9. Complexes 8 and 9, which contain a 'free ylide' functionality, react with ClAu(tht) to give [Pt{C₆H₄-2-PPh₂C(H)COCH(AuCl)PPh₃}(dppe)](ClO₄), 10, and [Pt{C₆H₄-2-PPh₂C(H)COCH(AuCl)PPh₃}(PPh₃)₂](ClO₄), 11. In the heterobimetallic complexes 10 and 11 the ylide ligand acts as a C,C,C-terdentate ligand and, in spite of the presence of two chiral centers, only one diastereoisomer (as the mixture of two enantiomers) is observed. All complexes were characterized on the basis of their spectroscopical and analytical parameters.

Full text of DOI:10.1039/b002848g

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Synthesis and reactivity of PtII complexes containing the
orthometallated ligand [C H -2-PPh C(H)COCH PPh ]
6 4
2
2
3
Carmen Larraz, Rafael Navarro* and Esteban P. Urriolabeitia
Departamento de Qu•mica Inorganica, Instituto de Ciencia de Materiales de Aragon, Universidad
de ZaragozaÈConsejo Superior de Investigaciones Cient•Ðcas, E-50009 Zaragoza, Spain. E-mail:
rafanava=posta.unizar.es, esteban=posta.unizar.es; http://lrÑ.unizar.es/Dnavarro/c Rafa.html
–
Received (in Montpellier, France) 7th April 2000, Accepted 12th May 2000
Published on the Web 7th July 2000
The reaction of PtCl (NCPh) with the ylide [Ph P2C(H)COCH PPh ]ClO (1 : 1 molar ratio, reÑuxing CHCl )
2
2
3
2
3
4
3
a†ords trans-[PtCl (NCPh)MC(H)PPh C(O)CH PPh N]ClO 1. However, the reaction of PtCl (CH Cl , r.t.) or
2
3
2
3
4
2
2 2
PtCl (NCMe) (2-methoxyethanol, reÑux) with the ylide [Ph P2C(H)COCH PPh ]ClO (1 : 1 molar ratio) a†ords
2
2
3
2
3
4
the orthometallated [PtMC H -2-PPh C(H)COCH PPh N(l-Cl)] (ClO ) , 2, as a mixture of diastereoisomers 2aÈd.
4 2
6
4
2
2
3
2
Treatment of 2 with PPh (1 : 2 molar ratio) a†ords [PtClMC H -2-PPh C(H)COCH PPh N(PPh )](ClO ), 3, as a
3
6
4
2
2
3
3
4
single geometric isomer. The reaction of 2 with AgClO (1 : 2 molar ratio) in NCMe gives the solvato complex
4
[PtMC H -2-PPh C(H)COCH PPh N(NCMe) ](ClO ) , 4, while the reaction of 2 with Tl(acac) (1 : 2 molar ratio)
6
4
2
2
3
2
4 2
gives [PtMC H -2-PPh C(H)COCH PPh N(acac)](ClO ), 5. The dicationic complexes [PtMC H -2-
6
4
2
3
2
3
4
6
6 4
PPh C(H)COCH PPh N(dppe)](ClO ) , 6, and [PtMC H -2-PPh C(H)COCH PPh N(phen)](ClO ) , 7, can be
2
2
4 2
4
2
2
3
4 2
obtained by reaction of 2 with AgClO followed by addition of the appropiate ligand (1 : 2 : 2 molar ratio). The
4
reaction of 6 with NaH gives [PtMC H -2-PPh C(H)COCH2PPh N(dppe)](ClO ), 8, while the reaction of 4 with
6
4
2
3
3 2
4
PPh and NaH gives [PtMC H -2-PPh C(H)COCH2PPh N(PPh ) ](ClO ), 9. Complexes 8 and 9, which contain a
3
6
4
2
3
4
““free ylideÏÏ functionality, react with ClAu(tht) to give [PtMC H -2-PPh C(H)COCH(AuCl)PPh N(dppe)](ClO ), 10,
6
4
2
3
4
and [PtMC H -2-PPh C(H)COCH(AuCl)PPh N(PPh ) ](ClO ), 11. In the heterobimetallic complexes 10 and 11 the
6
4
2
3
3 2
4
ylide ligand acts as a C,C,C-terdentate ligand and, in spite of the presence of two chiral centers, only one
diastereoisomer (as the mixture of two enantiomers) is observed. All complexes were characterized on the basis of
their spectroscopical and analytical parameters.
One of our main current resarch subjects is the coordination
ylides are actually more complicated, giving di†erent types of
chemistry of PdII and PtII with a-stabilized phosphoylides.1
CÈC bond coupling products,31h33 resulting from the nucleo-
Amongst them, the neutral bis-ylide [C(H)2PPh ] CO has
philic attack of the C of the ylide on the nitrilic carbon. Thus,
3 2
a
shown a notable reactivity, not only in PdII derivatives2h5 but
several reactivity patterns should be considered in this kind of
also in gold and silver complexes, as it has been reported by
other research groups.6 One of the most interesting reactions
of this bis-ylide is its intramolecular rearrangement from the
reaction.
In this paper, we report di†erent synthetic methods to
achieve the orthometallation of the phosphonium ylide
[Ph P2C(H)C(O)CH PPh ]ClO promoted by PtII complex-
C,C-chelating form [C(H)PPh ] CO to the C,C-orthometal-
3 2
3
2
3
4
lated form [C H -2-PPh C(H)COCH PPh ],3 which can be
es. Interestingly, the reactions of the nitrile precursors
PtCl (NCPh) and PtCl (NCMe) with the aforementioned
6
4
2
2
3
induced through a variety of methods. This rearrangement
2
2
2
2
occurs through a CÈH bond activation process in one Ph
phosphonium ylide proceed without attack over the coordi-
nated nitriles and, in some cases, a†ord the orthometallated
derivatives under very mild conditions (CH Cl , r.t.). We have
group of a PPh fragment, followed by an acid-base intramol-
3
ecular reaction.3 PtII complexes have been employed frequent-
2
2
ly to promote CÈH bond activation,7 and interest in
cycloplatination reactions is growing continuously (as evi-
denced by the number of contributions that have appeared in
this Ðeld8h20), because of their practical importance.21 On the
other hand, although the orthometallation of ylide ligands is a
known reaction, not only for the platinum group metals22h29
but also in early transition metals such as Nb,30 the sub-
sequent reactivity of the orthometallated ylide ligands has
been rarely reported.4,5,24
also studied the reactivity of the C,C-orthometallated deriv-
atives [PtMC H -2-PPh C(H)COCH PPh NL ]n` towards
6
4
2
2
3
n
deprotonating reagents, which results in the syn-
thesis of ““free-ylideÏÏ-containing complexes [PtMC H -2-
6
4
PPh C(H)COCH2PPh NL ](n~1)` and their subsequent reac-
2
3
n
tivity towards electrophilic reagents, such as ClAu(tht)
(tht \ tetrahydrothiophene), to a†ord the heterobimetallic
species [PtMC H -2-PPh C(H)COCH(AuCl)PPh NL ](n~1)`,
6
4
2
3
n
in which the orthometallated ylide group acts as a C,C,C-terd-
Due to our interest in CÈH bond activation processes and
in orthometallated systems derived from ylide groups, we have
decided to explore the reactivity of some simple complexes of
PtII such as PtCl or PtCl (NCR) (R \ Me, Ph) towards the
entate ligand.
Results and discussion
Reactivity of PtCl (NCR) and PtCl with
2
2
2
phosphonium ylide salt [Ph P2C(H)C(O)CH PPh ]ClO . In
2
2
2
[Ph P2C(H)C(O)CH PPh ]ClO
4
3
2
3
4
the case of the nitrile complexes one should expect, at a Ðrst
glance, a simple displacement of the coordinated nitrile by the
incoming ylide, but it has been previously reported that the
reactions of PtCl (NCR) (R \ Me, Ph, C F ) with stabilized
3
2
3
The reaction of PtCl (NCPh)
with [Ph P2C(H)
2
2
3
C(O)CH PPh ]ClO (1 : 1 molar ratio, CHCl , reÑux, 5 h)
2
3
4
3
results in the formation of trans-[PtCl (NCPh)- MC(H)PPh -
2
2
6 5
2
3
DOI: 10.1039/b002848g
New J. Chem., 2000, 24, 623È630
623
This journal is ( The Royal Society of Chemistry and the Centre National de la Recherche ScientiÐque 2000

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C(O)-CH PPh N]ClO , 1, eqn. (1), according to its analytical
dissolved. After Ðltration, removal of the solvent and Et O
addition, the mixture of the orthometallated complexes 2aÈd
2
3
4
2
and spectroscopic data (see Experimental). The reaction
occurs by simple displacement of only one coordinated nitrile
and its substitution by the ylide, which coordinates through
the ylidic C atom. This result contrasts with related reports of
the reactivity of PtII-nitrile complexes with a-keto-stabilized
ylides R P2C(H)CO R, which result in the attack of C on the
is obtained as a cream solid [see eqn. (2) (top)]. The presence
of four isomers can be inferred from the NMR spectra (see
below and Experimental) but two of the isomers, 2a and 2b,
are always present in higher amounts than the other two, 2c
and 2d.
3
2
a
coordinated nitrile.31h33 The di†erence in the observed reacti-
vity could be related to the di†erent basicity associated with
the ylidic carbon.
The mild conditions employed in the cycloplatination of the
phosphonium ylide [Ph P2C(H)C(O)CH PPh ]ClO contrast
3
2
3
4
with the previous reports of orthometallation of stabilized
The stretching l(CO) band appears at 1654 cm~1 in the IR
spectrum, clearly shifted to higher frequencies with respect to
the starting ylide (1590 cm~1)6 and suggesting its C-
coordination. The Cl-trans-to-Cl geometry of 1 can be inferred
from the observation of only one PtÈCl absorption (309
cm~1), and the presence of coordinated NCPh from the
absorption located at 2300 cm~1. The 1H NMR spectrum
shows the resonance attributed to the ylidic CH proton at
6.22 ppm, as a broad singlet, and Ñanked by 195Pt satellites.
ylides. Thus, the ylide Ph P2C(H)COMe is orthometallated
3
by reaction with PtCl in reÑuxing NCMe for 44 h,22 while
2
the complex trans-PtCl MC(H)PPh C(O)MeN evolves in
2
3
2
reÑuxing THF (8 h) or reÑuxing NCMe (44 h), resulting in
the
formation
of MPtCl [CH(COCH )PPh (o-C H )]-
2
3
2
6 4
[Ph PCH COCH ]N.26 However, the authors also reported
that the latter transformation can also be performed in
3
2
3
CH Cl at room temperature for several days.26
2
2
In order to shed light on the kinetic or thermodynamic
nature of the di†erent pairs of isomers 2a, b and 2c, d
obtained and since the orthometallation of the ylides
is usually promoted at high temperatures, we have
The value of the coupling constant 2J
\ 117 Hz is in good
PtvH
agreement with previously reported values for PtII C-bonded
ylides.26,34 This spectrum shows also the presence of the AB
part of an ABX spin system, attributed to the methylene
protons of the ÈCH PPh group (see Experimental). In addi-
reÑuxed equimolar amounts of PtCl (NCMe)
and
2
2
[Ph P2C(H)C(O)CH PPh ]ClO in di†erent solvents. The
2
3
3
2
3
4
tion, the 31PM1HN NMR spectrum shows the two chemically
best results were obtained in 2-methoxyethanol, a solvent that
has been employed in the orthometallation of bulky tertiary
inequivalent P atoms as two doublets (4J \ 10 Hz), one of
PvP
them showing 195Pt satellites (2J \ 76 Hz), and the
PtvP
phosphines.36
The
reaction
of
PtCl
with
2
13CM1HN NMR spectrum conÐrms the C-bonding of the ylide
[Ph P2C(H)C(O)CH PPh ]ClO in 2-methoxyethanol [1 : 1
3
2
3
4
[Ph PC(H)C(O)CH PPh ]ClO since the ylidic carbon
molar ratio, reÑux, 5 h, see eqn. (2) (bottom)] results in the
almost exclusive formation of the isomers 2c, d according to
the NMR data. Thus, it seems that the isomers obtained at
room temperature, 2a, b, are the kinetic isomers and those
obtained at higher temperatures, 2c, d, are the thermodynamic
isomers. Additional proof comes from the observation that a
mixture of 2a, b subjected to prolonged heating in 2-
methoxyethanol evolves to a mixture of 2c, d.
3
2
3
4
appears at 21.52 ppm as a doublet of doublets, although due
to the low intensity of the resonance we were unable to Ðnd
the corresponding platinum satellites. The presence of coordi-
nated NCPh was also evident from the 13CM1HN NMR spec-
trum since the nitrilic carbon appears at 114.99 ppm, typical
for coordinated nitriles.35
Complex 1 has the ylide [Ph PC(H)C(O)CH PPh ]ClO
3
2
3
4
selectively coordinated through the ylidic carbon. This result
contrasts with those obtained in PdII complexes, in which we
were unable to obtain this coordination mode.2 As far as we
know, only one example of this bonding mode has been
The mixture of complexes 2aÈd has elemental analysis and
mass spectrum in accordace with the stoichiometry
[Pt(Cl)(C H PPh C(H)COCH PPh )] (ClO ) (see Experi-
6
4
2
2
3 2
4 2
mental). Moreover, its IR spectrum shows the carbonyl stretch
at 1652 cm~1 and the absorptions corresponding to the PtÈCl
stretch at 283 cm~1, shifted to lower energies when compared
with 1, suggesting the presence of bridging halide ligands.
The characterization of complexes 2aÈd as a mixture of dia-
stereoisomers containing the orthometallated [C H -2-
reported,
the
gold(I)
derivative
[AuClMCH(PPh )-
3
COCH PPh N]ClO .6 Owing to the presence of the phos-
2
3
4
phonium moiety in 1, and due to our recent experience in the
deprotonation of related systems,4,5 we have performed
several reactions in order to obtain PtII derivatives with the
6 4
PPh C(H)COCH PPh ] ligand has been made on the basis of
C,C-chelating ligand [C(H)PPh ] CO, which should arise
3 2
2
2
3
from direct deprotonation of 1 and simultaneous abstraction
their NMR data. The 1H NMR spectrum of 2aÈd shows the
presence of four di†erent resonances attributed to the ylidic
PtÈCH protons and four AB parts of ABX spin systems,
attributed to the methylene protons of the ÈCH PPh groups
(X \ 31P nucleus). The 31PM1HN NMR of 2aÈd shows also the
presence of four sets of AX spin systems: the part A of the
resonances appears centered around 20 ppm (ÈCH PPh ) and
of one chloride ligand. However, the reactivity of 1 towards
deprotonating reagents such as NaH (1 : 1 molar ratio, THF,
r.t.), NBu OH (1 : 1 molar ratio, MeOH, r.t.), Tlacac (1 : 1 or
4
2
3
1 : 2 molar ratio, CHCl , r.t. or reÑux) or (acac)AuPPh (1 : 1
3
3
molar ratio, CH Cl , r.t.) only gave intractable mixtures of
several products, which were not analyzed further.
2
2
2
3
Other reactions were performed in order to obtain com-
plexes related to 1 with the ylide C-bonded. However,
the part X appears spread from 24 to 30 ppm (PPh ). The
2
13CM1HN NMR spectrum provides fundamental evidence for
the presence of the orthometallated C,C-chelating ligand
[C H -2-PPh C(H)COCH PPh ]. Thus, the APT spectrum
PtCl (NCMe)
does not react with [Ph P2C(H)-
2
2
3
C(O)CH PPh ]ClO under the same conditions (1 : 1 molar
2
3
4
6
4
2
2
3
ratio, CHCl , reÑux, 5 h) and the starting materials were
(attached proton test) shows negative doublet resonances in
3
recovered. Probably, the di†erent lability of the two nitrile
(2)
ligands accounts for this di†erent reactivity. Moreover, PtCl
2
reacts with [Ph P2C(H)C(O)CH PPh ]ClO (1 : 1 molar
3
2
3
4
ratio, CH Cl , r.t., 4 days) but gives a very di†erent complex.
2
2
At the end of the reaction time, the PtCl is almost completely
2
(1)
624
New J. Chem., 2000, 24, 623È630

View Article Online
the range 135È144 ppm, the typical region for the appearance
195Pt satellites (a broadening of the base of the signal) and the
phosphonium group appears at 20.17 ppm as a doublet.
The synthesis of 3 as a single isomer resembles that of the
of the orthometallated C carbon atom Mthe reported value
1
for [Pt(l-Cl)CH COCHP(C H )(C H ) ] É 2 CDCl is 136.9
ppm).22
3
6
4
6
5 2 2
3
related
Pd(II)
derivative
[Pd(Cl)MC H -2-PPh C(H)-
6
4
2
Once the orthometallated dinuclear nature of complexes 2
is established, the explanation of the presence of four di†erent
isomers could be explained by assuming that we have two
COCH PPh N(PPh )](ClO ).3 In the Pd(II) complex, this
2
3
3
4
selectivity was explained taking into account the anti-
symbiotic behavior of the soft Pd(II) metal center,1,37h41 and
similar arguments can be invoked here to explain this similar
selectivity of the soft Pt(II) center.37,39 In our experience, in all
complexes of PdII and PtII containing the neutral orthometal-
lated ligand [C H -2-PPh C(H)COCH PPh ], the coordi-
nation of an incoming phosphine ligand always occurs at the
trans position to the ylidic carbon. It has been recently report-
ed that the mutual destabilizing e†ect of trans ligands
increases with their trans inÑuence.41 According to this e†ect,
and taking into account that the trans inÑuence of the aryl
di†erent
arrangements
of
the
[Pt(Cl)(C H PPh -
6
4
2
C(H)COCH PPh )] fragments: syn and anti. In turn, the syn
2
3
isomer possess two chiral centers (the two ylidic carbon atoms
bonded to the Pt center) and thus we have again two pos-
sibilities: syn (RR/SS) and syn (RS/SR), which appear as two
di†erent products. In the same way, we could have anti
(RR/SS) and anti (RS/SR) thus giving four di†erent diastereo-
isomers, each as the racemic mixture of two enantiomers. The
assignment of the anti isomers to the products 2c, d has been
made by similarity of the chemical shifts, and of the shape of
the resonances of the 1H NMR spectrum of the mixture, with
those observed in the corresponding PdII complex3 [Pd(l-Cl)
MC H -2-PPh C(H)COCH PPh N] (ClO ) , which proved to
6
4
2
2
3
group is higher than that of the phosphine ligand (Ar [ PR ),
3
the decreasing order of destabilizing e†ects should be
Ar/Ar [ Ar/PR [ PR /PR .41 This e†ect has been called
3
3
3
transphobia.41,42
6
4
2
2
3
2
4 2
be the anti isomers.4 Thus, the compounds 2a, b have been
We can now propose the inclusion of a new member in this
sequence, according to our experimental data. Since it seems
assigned to the syn isomers.
With respect to the mechanism of the orthometallation, we
have some evidence to believe that the reaction in CH Cl
that the trans inÑuence decreases in the order Ar [ C
[
ylide
PR , the latter sequence of destabilizing e†ects could be
2
2
3
occurs in a similar way to that described26 for the cyclo-
extended
as
follows:
Ar/Ar [ Ar/C
[ Ar/PR [
ylide
3
platination of [PtCl MC(H)PPh C(O)MeN ]. In this report, the
C
/PR [ PR /PR , though we do not yet have experi-
2
3
2
ylide
3
3
3
intramolecular metallation seems to be promoted by the
presence of traces of HCl and it is completely inhibited in the
presence of K CO . In the same way, we have performed the
mental evidence to include in a precise position the term
C
/C
. The trends described here have found wide
ylide ylide
support in the experimental work.
2
3
reaction
of
PtCl
with
equimolar
amounts
of
Nevertheless, we are aware of the existence of exceptions to
this rule, some of which have been reported by us4 and by
other authors,25 but, in general, the transphobia rule gives
accurate predictions. It is clear that antisymbiosis and the
trans inÑuence are not the sole parameters governing the Ðnal
stereochemistry of a given complex. For instance, subtle varia-
tions in the ligands can alter dramatically the predicted
stereochemistry, as in the case of [Pd(Cl)MC H -2-
2
2
[Ph P2C(H)C(O)CH PPh ]ClO in CH Cl and in THF, in
the presence or absence of Na CO , and we have observed
cycloplatination only in the reaction carried out in CH Cl in
3
3
4
2 2
2
3
2
2
the absence of Na CO (all reactions at room temperature).
2
3
We have not performed experiments in order to ascertain
which mechanism operates in the thermal orthometallation in
2-methoxyethanol.
6
4
PPh C(H)COCH PPh N(PPh )](ClO ) (1 isomer)3 and
2
2
3
3
4
[Pd(Cl)MC H -2-PPh C(H)COCH2PPh N(PPh )]
(2
iso-
Reactivity of the cycloplatinated derivatives 2a–d
6
4
2
3
3
mers),4 for which the only di†erence is the presence of a phos-
phonium fragment or an ylide group, respectively, or in the
case of the complex [PdClMj2-C H [PTo -CH(Py-2@)-2]Me-
Obviously, the reactivity of the four isomers in cleavage reac-
tions of the chloride bridging system is the same. The reaction
6
3
2
of 2aÈd (di†erent molar ratios a : b : c : d) with PPh (1 : 2
4N(PEt )],25 which is obtained as a mixture of two isomers
3
3
molar
ratio)
gives [Pt(Cl)MC H -2-PPh C(H)COCH -
(PEt trans C and PEt trans C ).
6
4
2
2
3
aryl
3
ylide
PPh N(PPh )](ClO ), 3, as a single isomer and in good yields
(see Scheme 1). When the reaction is monitored by 31PM1HN
NMR (CD Cl , r.t.) the spectroscopic yield of 3 is 100%, and
we have not detected unreacted 2 in the solution, nor other
isomers of 3. Complex 3 was obtained, in preparative scale,
after evaporation of the solvent to dryness and addition of
On the other hand, the solvate [PtMC H -2-
3
3
4
6 4
can be
PPh C(H)COCH PPh N(NCMe) ](ClO ) ,
4,
2
2
3
2
4 2
obtained, as a white solid, by reaction of the mixture 2aÈd
with AgClO (1 : 2 molar ratio) in NCMe at room tem-
perature, Ðltration of the precipitated AgCl, evaporation of
2
2
4
the solvent to dryness and treatment of the oily residue with
n-hexane. The elemental analysis and mass spectrum of 4 are
in good agreement with the proposed stoichiometry. The pres-
ence of two NCMe ligands can be inferred from the IR spec-
trum (absorptions at 2322 cm~1), which also shows the l(CO)
band at 1670 cm~1. The 1H NMR spectrum shows the pres-
ence of resonances attributed to two nitrile ligands (two sing-
lets at 2.46 and 2.41 ppm), to the ylidic CH proton (a doublet
at 5.33 ppm) and to the methylene protons. The last resonance
appears as a doublet (instead of a well-resolved AB spin
system), probably due to isochrony of the two protons, which
MeOH or Et O as a white solid. Its elemental analysis and
2
mass spectrum are in good agreement with the proposed stoi-
chiometry. The IR spectrum of 3 shows the carbonyl absorp-
tion at 1643 cm~1 and the PtÈCl stretch at 283 cm~1, typical
for a terminal chloride trans to a carbon atom.26 Further
characterization of 3 comes from the analysis of its NMR
data. The 1H NMR spectrum shows only one set of reso-
nances, suggesting the presence of a single geometric isomer.
The ylidic CH proton appears at 4.84 ppm as a doublet of
doublets of doublets, due to its coupling with three di†erent P
atoms, and suggesting that the PPh ligand is trans to the
ylidic carbon, as it has been observed in its Pd homolog. The
transforms the AB spin system into an A system.43 This
3
2
deceptively simple A spin system is coupled with the 31P
2
methylenic CH P protons appear at 4.95 and 5.73 ppm, as the
nucleus with the same coupling constant (2J \ 12.3 Hz).
2
PvH
AB part of an ABX spin system (X \ 31P). The 31PM1HN
The 31PM1HN NMR spectrum shows, as expected, an AX spin
system (30.03 and 21.06 ppm).
NMR spectrum of 3 shows the presence of only one set of
three resonances, corresponding to the three chemically ine-
The chlorine ligands in 2 can be substituted by the acac
ligand (acac \ acetylacetonate) by reaction of 2 with Tl(acac)
(1 : 2 molar ratio, CH Cl , r.t.). After removal of the TlCl and
quivalent P nuclei of the molecule. The coordinated PPh
3
appears at 24.10 ppm as a doublet with 195Pt satellites
2
2
(1J \ 3623 Hz), the P atom in the cycloplatinated ring
solvent
evaporation,
the
complex
[PtMC H -2-
PtvP
6 4
appears at 21.90 ppm as a doublet of doublets with unresolved
PPh C(H)COCH PPh N(acac)](ClO ), 5, (see Scheme 1) was
2
2
3
4
New J. Chem., 2000, 24, 623È630
625

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2J \ 3J
PvH
\ 6.3 Hz) with 195Pt satellites (2J
\ 80
PtransvH
PtvH
Hz) and the diastereotopic CH P protons (4.29 and 3.78 ppm)
2
as the AB part of an ABX spin system. The 31PM1HN NMR
spectrum of 6 shows the presence of four resonances corre-
sponding to the four chemically inequivalent P atoms of the
molecule. For complex 7, the CH (ylide) proton appears at
5.80 ppm and the CH P protons at 5.47 and 5.15 ppm. As
expected, the 31PM1HN NMR spectrum of 7 shows an AX spin
system (26.55 and 20.79 ppm).
2
Deprotonation of complexes 3–7
Owing to the presence of the phosphonium group
ÈC(O)CH PPh in complexes 3È7, we have attempted the
2
3
deprotonation of these compounds with a variety of bases in
order to obtain neutral or monocationic derivatives contain-
ing the free ylide unit ÈC(O)C(H)2PPh , in a similar way to
3
that described for Pd complexes.4 However, the reactivity of
3È7 with bases such as NBu OH, which have given excellent
4
results in Pd complexes,4 did not give clean reactions in this
case and complex mixtures were obtained. The same results
were observed in the reaction of 3 with NaH, and the reaction
of 4 or 5 with NaH was not attempted.
The reactivity of 6 with NaH was more successful. Thus,
the treatment of a THF suspension of 6 with an excess of
NaH a†ords the monocationic derivative [PtMC H -2-
Scheme 1
6
4
PPh C(H)COCH2PPh N(dppe)](ClO ), 8, (see Scheme 2)
2
3
4
obtained, according to its elemental analysis and mass spec-
trum. The spectroscopic data of 5 are also in keeping with the
proposed stoichiometry. The IR spectrum shows absorptions
attributed to the carbonyl stretch of the ylide (1656 cm~1) and
to the acac ligand (1558 and 1520 cm~1). The 1H NMR shows
the expected resonances for the CH (acac) proton (5.24 ppm),
the CH P protons (5.25 ppm), the CH (ylide) proton (4.71
ppm) and the methyl (acac) protons (1.89 and 1.58 ppm). Once
again, the 31PM1HN NMR spectrum shows an AX spin system
according to its elemental analysis and mass spectrum (see
Experimental). The IR spectrum of 8 shows the carbonyl
absorption at 1529 cm~1, that is, shifted 128 cm~1 to lower
energies with respect to the starting compound 6 and in good
agreement with the presence of the free ylide unit
ÈC(O)C(H)2PPh . The NMR spectra provide further charac-
3
terization. The 1H NMR spectrum shows, in addition to the
2
aromatic resonances and those expected for the methylene
protons of the dppe ligand, a triplet centered at 4.15 ppm
(attributed to the PtÈCH proton) and a new doublet at 3.09
ppm (relative intensity 1 : 1). This last resonance showing a
(30.36 and 21.12 ppm).
Finally, dicationic complexes of stoichiometry [PtMC H -2-
6
4
PPh C(H)COCH PPh N(L-L)](ClO ) (L-L \ dppe 6, phen 7)
value of the coupling constant 2J of 25.2 Hz, very similar to
2
2
3
4 2
PvH
can be obtained by reaction of 2 with AgClO (1 : 2 molar
those observed for the free ylides, and which is attributed to
4
ratio, THF, r.t) (see Scheme 1), Ðltration of the AgCl, and sub-
the ylidic proton of the ““free ylideÏÏ group. The 31PM1HN
NMR is also in good agreement with the proposed stoichiom-
etry, since the resonance at 21.13 ppm in the starting product
6 is not observed and a new resonance at 13.60 ppm appears,
corresponding to the free ylide phosphorus.
sequent addition of the L-L ligands (molar ratio 2 : L-
L \ 1 : 2) to the resulting solution of the solvated species
[PtMC H -2-PPh C(H)COCH PPh N(THF) ](ClO ) .
The
6
4
2
2
3
x
4 2
analytical and spectroscopic data of 6 and 7 are in good
agreement with the proposed stoichiometry. The IR spectra
show absorptions attributed to the carbonyl stretch of the
ylide, which in both cases appears at 1657 cm~1. The 1H
NMR spectra shows the expected resonances for the dppe or
the phen groups in an asymmetric environment (inequivalence
of the two halves of each ligand). In addition, the 1H NMR
spectrum of 6 shows the CH (ylide) as a triplet (5.36 ppm,
The synthesis of complex [PtMC H -2-PPh C(H)-
6
4
2
COCH2PPh N(PPh ) ](ClO ), 9, (see Scheme 2) is not as
3
3 2
4
straightforward as that described for complex 8. The reaction
of the bis-acetonitrile complex 4 with an excess of PPh
3
should result in the replacement of the two NCMe ligands by
two PPh groups or, at least, in the exchange of one NCMe
3
by one PPh , giving the complex [PtMC H -2-
3
6 4
Scheme 2
626
New J. Chem., 2000, 24, 623È630

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PPh C(H)COCH PPh N(PPh )(NCMe)](ClO ) , by analogy
4 2
to the observed behavior in Pd(II) complexes.3 Thus, although
in the IR spectra of the l(AuÈCl) stretch at 340 (10) and at 329
cm~1 (11), the typical region for the Cl trans to C(ylide).6 The
1H and 31PM1HN NMR spectra of 10 and 11 show the
expected changes for the new stereochemistry. The resonances
at 13.60 (8) or 14.37 ppm (9) in 31P have moved to 25.49 (10)
and 27.12 ppm (11), respectively, suggesting the C-bonding to
the [AuCl] fragment. Moreover, and this fact was somewhat
expected, complexes 10 and 11 have been obtained as single
diastereoisomers, in spite of the presence of two chiral centers
(one ylidic carbon C-bonded to platinum and one ylidic
carbon C-bonded to gold). In fact, only one set of signals is
observed in the NMR spectra (within the detection limits of
the spectrometer), suggesting the presence of only one dia-
stereoisomer. This behavior has already been observed in
2
2
3
3
the bis-phosphine derivative
PPh C(H)COCH PPh N(PPh ) ](ClO )
[PdMC H -2-
6
4
could not be
2
2
3
3 2 4 2
complex
obtained,
the
[PdMC H -2-
6
4
PPh C(H)COCH PPh N(PPh )(NCMe)](ClO ) , containing
2
2
3
3
4 2
one PPh group, was synthesized in high yield and character-
3
ized crystallographically.3 However, by reaction of 4 with
PPh in di†erent molar ratios, we have not been able to
obtain a compound with a deÐned stoichiometry by simple
3
exchange of ligands.
Nevertheless, we have attempted the deprotonation of 4 in
the presence of PPh . Thus, a suspension of 4 in THF was
3
treated with an excess of PPh , resulting in the gradual disso-
3
lution of the starting compound. This solution was then
gold6
complexes
with
the
bis-ylide
Ph P2C(H)È
3
allowed to react with NaH, and the subsequent workup
(see Experimental) gives the desired deprotonated compound
C(O)ÈC(H)2PPh , in palladium complexes with the same bis-
3
ylide2, and in heterodinuclear PdAu and trinuclear Pd Hg
complexes with the C,C,C-terdentate orthometallated ligand
2
[PtMC H -2-PPh C(H)COCH2PPh N(PPh ) ](ClO ),
9,
6
4
2
3
3 2
4
although in moderate yield (58%). This behavior is somewhat
related to that observed in the palladium complexes.
C H -2-PPh C(H)COCH(ML )PPh .4 According to these
6
4
2
n
3
precedents, we can propose that the absolute conÐgurations of
Thus,
although
[PdMC H -2-PPh C(H)COCH PPh N-
the diastereoisomers obtained in 10 and 11 are the meso forms
6
4
2
2
3
(PPh ) ](ClO ) could not be3 synthesized, its deprotonated
(R
S
/S
R
).
3 2 4 2
CvPd CvAu CvPd CvAu
Conclusions
form
[PdMC H -2-PPh C(H)COCH2PPh N(PPh ) ](ClO )
6
4
2
3
3 2
4
can be obtained and it is stable, both in the solid state and in
solution.5
In conclusion, the reactivity of PtCl or PtCl (NCR) with the
2
2
2
The elemental analysis and mass spectrum of 9 are in good
agreement with the proposed stoichiometry. The IR spectrum
shows the carbonyl stretch at 1531 cm~1, in the same region
as that observed for 8. The 1H NMR spectrum shows the
presence of a very complex multiplet with 195Pt satellites at
3.62 ppm, attributed to the ylidic PtÈC(H) proton and a
doublet at 3.89 ppm, with a value of the coupling constant
phosphonium ylide [Ph P2C(H)COCH PPh ]` allows the
3
2
3
synthesis of two types of derivatives: the C-bonded complex
(1) and new cycloplatinated compounds derived from CÈH
bond activation (2aÈd). The reactivity of 2aÈd produces
cationic complexes containing the orthometallated C,C-che-
lating ligand [C H -2-PPh C(H)COCH PPh ] (3È7) which,
in turn, can be deprotonated to give PtII derivatives with the
anionic ligand [C H -2-PPh C(H)COCH2PPh ]~ (8, 9). The
latter are adequate starting materials for the synthesis of
bimetallic species (10, 11) with the C,C,C-terdentate ligand
[C H -2-PPh C(H)COCHPPh ]~.
6
4
2
2
3
2J of 26.1 Hz. Both facts are in keeping with the presence of
PvH
6
4
2
3
the free ylide group ÈC(O)ÈC(H)2PPh . The 31PM1HN NMR
3
spectrum shows the presence of four chemically inequivalent P
atoms, as expected for the proposed stoichiometry and
showing that two PPh ligands have replaced two NCMe
groups. Moreover, the resonance located at 14.37 ppm pro-
vides additional evidence for the presence of the free ylide
6
4
2
3
3
Experimental
Caution! Perchlorate salts of metal complexes with organic
ligands are potentially explosive. Only small amounts of these
materials should be prepared and they should be handled with
great caution. See ref. 45.
group ÈC(O)ÈC(H)2PPh .
3
Synthesis of heterobimetallic complexes
We have also attempted the synthesis of bimetallic derivatives
through two di†erent methods. The Ðrst one is the reaction of
General procedures
Solvents were dried and distilled under nitrogen before use:
diethyl ether and tetrahydrofuran over benzophenone ketyl,
dichloromethane and chloroform over P O , acetonitrile over
the
phosphonium-containing
complexes
3È7
with
(acac)AuPPh (a method that had proved to be very efficient
3
in palladium complexes)4 and the second one is the reaction of
2
5
CaH , methanol over magnesium and n-hexane and toluene
the ylide complexes 8 and 9 with ClAu(tht). To our surprise,
2
over sodium. Elemental analyses were carried out on a
the reactivity of 3È7 with (acac)AuPPh did not give the
3
PerkinÈElmer 240-B microanalyser. Infrared spectra (4000È
200 cm~1) were recorded on a PerkinÈElmer 883 infrared
spectrophotometer from nujol mulls between polyethylene
sheets. 1H (300.13 MHz), 13CM1HN (75.47 MHz) and 31P(1HN
expected results, and very complex mixtures of products were
obtained.
The reactivity of 8 and 9 with ClAu(tht) (1 : 1 molar ratio)
was more succesful, and the heterodinuclear complexes
[PtMC H -2-PPh C(H)COCH(AuCl)PPh N(dppe)](ClO ), 10,
(121.49 MHz) NMR spectra were recorded in CDCl or
3
6
4
2
3
4
CD Cl solutions at room temperature (unless otherwise
and
[PtMC H -2-PPh C(H)COCH(AuCl)PPh N(PPh ) ]-
2
2
6
4
2
3
3 2
stated) on a Bruker ARX-300 spectrometer; 1H and 13CM1HN
were referenced using the solvent signal as internal standard
and 31PM1HN was externally referenced to H PO (85%).
(ClO ), 11, were obtained (see Scheme 2). These complexes
show correct elemental analyses and mass spectra for the pro-
4
posed stoichiometries.
3
4
Mass spectra (positive ion FAB) were recorded on a VG
Autospec spectrometer from CH Cl solutions. The starting
The IR spectra of 10 and 11 show the carbonyl stretch at
1621 (10) and at 1631 cm~1 (11), that is, shifted to higher ener-
gies when compared with the respective starting compounds 8
and 9, and slightly shifted to lower energies when compared
with the parent phosphonium derivatives 6 and 4, respectively
(although in the case of 4 this is not rigorous, since they
do not have the same ancillary ligands). Thus, we have the
2
2
compound [Ph P2C(H)C(O)CH PPh ](ClO ) was prepared
3
2
3
4
according to published methods.6
Syntheses
trans-[PtCl (NCPh){C(H)PPh –C(O)CH PPh } ](ClO ),
2
3
2
3
4
sequence
l(CO,
phosphonium) [ l(CO,
C-bonded
1. To a solution of PtCl (PhCN) (0.690 g, 1.47 mmol) in
2
2
ylide) [ l(CO, free ylide). This trend has already been
observed in similar situations.6,44 The presence of the
[AuÈCl] fragment can be clearly inferred from the observation
30 mL of CHCl , the phosphonium ylide salt
3
3
[Ph PC(H)COCH PPh ](ClO ) (1.00 g, 1.47 mmol) was
3
2
4
added and the resulting solution was reÑuxed for 5 h. After
New J. Chem., 2000, 24, 623È630
627

View Article Online
the reaction time, the solvent was evaporated to dryness and
PPh in ring, 2c, major, 4J \ 7.9 Hz), 22.96 (d, CH PPh )
2
PvP
2
3
the residue was treated with Et O (20 mL), giving 1 as a pale
22.91 (d, CH PPh ). 13CM1HN NMR (CD Cl ): d for the syn
2
2
3
2 2
yellow solid, which was Ðltered and air dried. Obtained: 1.40
isomers, 188.26 (dd, CO, 2a, major, 2J \ 4.8 Hz, 2J \ 1.8
PvC PvC
Hz), 186.26 (d, CO, 2b, minor, 2J \ 6.1 Hz), 144.81 (d, C ,
PvC
C H , 2b, minor, 2J \ 22.5 Hz), 141.93 (d, C , C H , 2a,
PvC
major, 2J \ 21.3 Hz), 136.77È117.02 (m, Ph ] C H , both
PvC
isomers), 39.88 (d, CH P, 2b, minor, 1J \ 64 Hz), 36.77 (dd,
PvC
g (91% yield).
1
Anal. calcd. for C
1.33. Found: C, 52.80; H, 3.61; N, 1.35. IR (cm~1): 1654 (l ),
H
Cl NO P Pt: C, 52.71; H, 3.65; N,
46 38
3
5 2
6
4
1
6 4
6 4
CO
309 (l
). FAB-MS [m/z, (%)]: 949 (17%) [M [ ClO ]` 1H
PtvCl
4
2
PvC
NMR (CD Cl ): d 8.00È7.25 (m, 35H, Ph), 6.22 (s, 1H, CHPt,
CH P, 2a, major, 1J \ 48 Hz, 3J \ 12.1 Hz), 35.32 (d,
2
2
2
PvC
2J
\ 117 Hz), 5.83 (dd, 1H, CH P, 2J \ 18.3 Hz,
HvH
2J \ 11.1 Hz), 5.69 (dd, 1H, CH P, 2J \ 12.3 Hz).
PvH PvH
31PM1HN NMR (CD Cl ): d 22.99 d, C(H)PPh , 4J \ 10
PvP
Hz, 2J \ 76 Hz), 18.89 (d, CH PPh ). 13CM1HN NMR
PtvP
CHPt, 2b, minor, 1J \ 59.5 Hz), 35.25 (d, CHPt, 2a, major,
PtvH
2
PvC
1J \ 62 Hz). The anti isomers were too insoluble for 13C
2
PvC
measurements, even in CD Cl .
2
2
3
2 2
2
3
[PtCl{C H -2-PPh C(H)COCH PPh }PPh ](ClO ), 3. To
(CD Cl ): d 197.43 (d, CO, 2J \ 3.69 Hz), 134.45 (d, J
\
6
4
2
2
3
3
2
4
2
2
PvC
PvC
PvC
a solution of 2 (0.25 g, 0.13 mmol) in CH Cl (20 mL) was
10.6 Hz), 134.02 (s), 134.00 (d, J \ 2.4 Hz), 133.87 (s), 130.48
2
added PPh (0.07 g, 0.27 mmol) and the resulting solution was
(d, J \ 13.1 Hz), 129.75 (d, J \ 12.5 Hz), 129.31 (s),
3
PvC
PvC
stirred at room temperature for 5 h. The solution was evapo-
121.69 (d, C , 1J \ 86 Hz), 118.76 (d, C , 1J \ 89
ipso
PvC
ipso
CvP
rated to dryness and the residue was stirred with MeOH (10
mL), giving 3 as a white solid that was Ðltered and air dried.
Obtained: 0.11 g (36% yield). A second fraction of pure 3 was
Hz) (PPh ), 114.99 (s, C3 N), 110.72 (s, C
NCPh), 39.28 (dd,
3
ipso
CH P, 1J \ 58.9 Hz, 3J \ 12.1 Hz), 21.52 (dd, CHPt,
2
PvC
PvC
1J \ 48.2 Hz, 3J \ 8 Hz).
PvC PvC
obtained after evaporation of the Ðltrate and Et O addition
2
(25 mL). Obtained: 0.07 g. Total yield of 3: 58%.
[Pt(l-Cl){C H -2-PPh C(H)COCH PPh } ] (ClO ) ,
6
4
2
2
3
2
4 2
Anal. calcd. for C
H
Cl O P Pt: C, 58.47; H, 4.04.
2a–d. Method (a). Finely ground PtCl (0.090 g, 0.36 mmol)
57 47
2 5 3
2
2
Found: C, 58.57; H, 3.94, IR (cm~1): 1643 (l ), 283 (l
).
was suspended in 50 mL of CH Cl . To this suspension
[Ph P2C(H)COCH PPh ](ClO ) (0.500 g, 0.73 mmol) was
CO
4
PtvCl
2
FAB-MS [m/z, (%)]: 1071 (27%) [M [ ClO ]`. 1H NMR
3
2
3
4
(CDCl ): d 8.00È7.00 (m, 44 H, Ph), 5.73 (dd, 1H, CH P,
added and this mixture was stirred at room temperature for 4
days. The resulting brown suspension was Ðltered, the Ðltrate
evaporated to dryness and the residue treated with PriOH (25
mL), giving a mixture of the syn (2a, 2b) and anti (2c, 2d) com-
plexes as a cream solid, which was Ðltered, washed with addi-
tional PriOH (10 mL) and n-hexane (20 mL). Obtained: 0.27 g
(82% yield). The molar ratios 2a : 2b : 2c : 2d may be di†erent
in di†erent preparations, but the anti derivatives always
appear as traces. Usually the molar ratio of the syn isomers is
major : minor \ 2 : 1.
3
2
2
2J \ 17.1 Hz, 2J \ 10.8 Hz), 4.95 (dd, 1H, CH P,
HvH PvH
2J \ 13.5 Hz), 4.84 (ddd, 1H, PtCH, 2J \ 8.7 Hz,
PvH PvH
3J \ 3.6 Hz, 4J \ 2.1 Hz). 31PM1HN NMR (CDCl ): d
PvH PvH
24.10 (d, 1P, PtÈPPh , 3J \ 18.8 Hz, 1J \ 3623 Hz),
PvP PvPt
21.90 (dd, 1P, PPh in ring, 4J \ 7.28 Hz), 20.17 (d,
PvP
3
3
2
CH PPh ).
2
3
[Pt{C H -2-PPh C(H)COCH PPh }(NCCH ) ]-
6
4
2
2
3
3 2
(ClO ) , 4. To a solution of 2 (0.25 g, 0.13 mmol) in NCMe at
4 2
room temperature (20 mL) AgClO (0.057 g, 0.27 mmol) was
added, resulting in the immediate precipitation of AgCl. The
Method (b) To a solution of PtCl (NCMe) (1.00 g, 2.64
mmol) in 25 mL of 2-methoxyethanol, [Ph P2C(H)-
COCH PPh ](ClO ) (1.79 g, 2.64 mmol) was added and the
4
2
2
resulting suspension was stirred for 1 h with exclusion of light,
then Ðltered, and the Ðltrate was evaporated to dryness. The
white residue was treated with n-hexane (10 mL), giving 4 as a
white solid that was Ðltered, washed with n-hexane (10 mL)
and air dried. Obtained: 0.22 g (77.60% yield).
3
2
3
4
resulting suspension was reÑuxed. After a short induction
period, the initial suspension dissolved almost completely and
the color of the solution changed gradually to o†-white (30
min). An o†-white solid precipitated during the remaining
reaction time (5 h). This solid was Ðltered, washed with PriOH
(10 mL) and n-hexane (15 mL), air dried and identiÐed as a
mixture of the syn (2a) and the anti (2c, 2d) isomers (molar
ratio anti : syn \ 2.77 : 1; anti isomers: molar ratio
major : minor \ 1.37 : 1). Obtained: 1.39 g (58.5% yield).
Further evaporation of the alcoholic solution to a small
volume (5 mL) and addition of PriOH (15 mL) yielded a
second crop of 2c, 2d (0.400 g, 16.7% yield). Total yield:
75.2%.
Anal. calcd. for C
H
Cl N O P Pt: C, 48.96; H, 3.63; N,
43 38
2 2 9 2
2.65. Found: C, 49.60; H, 3.52; N, 2.27. IR (cm~1): 2322 (l ),
CN
1670 (l ). FAB-MS [m/z, (%)]: 872 (100%) [M [ 2 NCMe
CO
[ ClO ]`. 1H NMR (CDCl ): d 8.00È7.00 (m, 29 H, Ph), 5.33
4
3
(d, CHPt, 1H, 2J \ 1.2 Hz), 5.13 (d, CH P, 2H, 2J \ 12.3
PvH
2
PvH
Hz), 2.46 (s, 3H, NCMe), 2.41 (s, 3H, NCMe). 31PM1HN NMR
(CDCl ): d 30.03 (d, PPh in ring, 4J \ 8 Hz), 21.06 (d,
3
2
PvP
CH PPh ).
2
3
[Pt{C H -2-PPh C(H)COCH PPh }(acac-O,Oº)](ClO )
6
4
2
2
3
4
Anal. calcd. for C
H
Cl O P Pt : C, 51.55; H, 3.55.
5. To a CH Cl solution (20 mL) of 2 (0.25 g, 0.13 mmol)
78 64
4 10 4 2
2
2
Found: C, 51.73; H, 3.98. IR (cm~1): 1652 (l ), 283 (l
).
Tl(acac) (0.08 g, 0.27 mmol) was added. The resulting suspen-
sion was stirred at room temperature for 5 h, then Ðltered.
The solvent was evaporated from the Ðltrate to dryness and
the residue was treated with n-hexane (20 mL), giving 5 as a
white solid, which was Ðltered, washed with n-hexane and air
dried. Obtained: 0.16 g (60.2% yield).
CO
4
PtvCl
FAB-MS [m/z, (%)]: 1717 (40%) [M [ ClO ]` 1H NMR
2
(CD Cl ): d for the syn isomers, 7.67È6.70 (m, Ph, both
2
2
isomers), 5.81 (dd, CH P, 2b, minor, 2J \ 16.2 Hz, 2J
\
2
HvH
PvH
12.6 Hz), 5.33 (d, CH
CH P, 2a, major, 2J \ 15.6 Hz, 2J \ 12.9 Hz), 4.91 (dd,
, 2a, major, 2J \ 3.9 Hz), 5.12 (dd,
ylide
PvH
2
HvH
PvH
CH P, 2b, minor, 1H, 2J \ 13.8 Hz), 4.90 (dd, CH P, 2a,
Anal. calcd. for C
H
ClO P Pt: C, 54.20; H, 4.03.
2
PvH
2
44 39
7 2
major, 2J \ 13.8 Hz), 4.47 (d, CH
PvH
, 2b, minor, 2J
\
Found: C, 54.26; H, 4.46. IR (cm~1): 1656 (l , ylide), 1558,
ylide
PvH
CO
2.7 Hz). d for the anti isomers, 7.86È7.09 (m, Ph, both isomers),
5.26 (dd, CH P, 2c, major, 2J \ 19.2 Hz, 2J \ 11.4 Hz),
1520 (l
,
acac). FAB-MS [m/z, (%)]: 872 (13%) [M
CO
[ ClO ]~. 1H NMR (CDCl ): d 8.04È6.66 (m, 29 H, Ph), 5.24
2
2
HvH
HvH
PvH
4
3
5.16 (dd, CH P, 2c, major, 2J \ 10.2 Hz), 4.89 (dd, CH P,
(s, 1H, CH-acac), 5.25 (br AB spin system, CH P, 2H, 2J
\
PvH
2
2
3
HvH
2d, minor, 2J \ 17.7 Hz, 2J \ 14.1 Hz), 4.68 (dd, CH P,
13.8 Hz), 4.71 (s, 1H, CHPt), 1.89 (s, 3H, CH -acac), 1.58 (s,
PvH
2
2d, minor, 2J \ 14.10 Hz), 4.69 (d, CH
PvH
, 2c, major,
3H, CH -acac). 31PM1HN NMR (CDCl ): d 30.36 (d, 1P, PPh
ylide
3
3
2
2J \ 1.5 Hz), 4.61 (t, CH
, 2d, minor, 2J \ 4J \ 2.1
in ring, 4J \ 7.7 Hz), 21.12 (d, CH PPh ).
PvH
ylide
PvH
PvH
PvP
2
3
Hz). 31P M1HN NMR (CD Cl ): d for the syn isomers, 25.89 (d,
2
2
PPh in ring, 2b, minor, 4J \ 5.5 Hz), 24.88 (d, PPh in
PvP
ring, 2a, major, 4J \ 4.6 Hz), 20.18 (d, CH PPh , 2b,
PvP
minor), 20.14 (d, CH PPh , 2a major). d for the anti isomers,
[Pt{C H -2-PPh C(H)COCH PPh }(dppe)](ClO ) , 6. To
2
2
6 4 2 2 3 4 2
a THF solution (30 mL) of 2 (0.25 g, 0.13 mmol) AgClO (0.05
2
3
4
g, 0.27 mmol) was added. The resulting suspension was stirred
2
3
32.10 (d, PPh in ring, 2d, minor, 4J \ 7.9 Hz), 30.59 (d,
PvP
at room temperature with exclusion of light for 30 min, then
2
628
New J. Chem., 2000, 24, 623È630

View Article Online
Ðltered. Dppe (0.10 g, 0.27 mmol) was added to the Ðltrate and
this solution was stirred for 1 h. Evaporation of the solvent
and n-hexane addition (20 mL) gave 6 as a white solid, which
was Ðltered and air dried. Obtained: 0.22 g (61% yield).
Complex 6 was recrystallized from a CH Cl ÈEt O (1 : 10)
3J \ 36.3 Hz, 1J \ 1856 Hz), 30.87 (ddd, 1P, PPh in
PvP
PvPt
2
ring, 4J \ 7.2 Hz), 13.60 (d, 1P, CH2PPh ).
PvP
3
[Pt{C H -2-PPh C(H)COC(H)2PPh }(PPh ) ](ClO ),
6
4
2
3
3 2
4
9. To a THF suspension (20 mL) of 4 (0.174 g, 0.16 mmol) was
2
2
2
added excess of PPh (0.130 g, 0.49 mmol). The suspension
gradually dissolved and to the resulting solution NaH (0.10 g,
mixture to gave 6 É 0.25 CH Cl as white crystals, which were
3
2
2
used for analytical and spectroscopic purposes. The amount of
excess) was added. This mixture was stirred at room tem-
perature overnight and then Ðltered. The Ðltrate was evapo-
rated to dryness, extracted with CH Cl (15 mL), Ðltered
CH Cl was determined by 1H NMR.
2
2
Anal. calcd. for C
H
Cl O P Pt É 0.25 CH Cl : C, 56.13;
65 56
2
9 4
2 2
H, 4.04. Found: C, 55.47; H, 3.52. IR (cm~1): 1657 (l ).
2
2
CO
again and the resulting solution evaporated to dryness to give
FAB-MS [m/z, (%)]: 1271 (8%) [M [ ClO ]`. 1H NMR
(CDCl ): d 7.94È6.75 (m, 49 H, Ph), 5.36 (t, CHPt, 1H,
4
9 as a white solid, which was collected with Et O (20 mL) and
2
3
air dried. Obtained: 0.130 g (58% yield).
2J \ 3J
\ 6.30 Hz, 2J
\ 80 Hz), 4.29 (dd, CH P,
PvH
PtransvH
PtvH
2
Anal. calcd. for C
H
ClO P Pt: C, 64.49; H, 4.40.
1H, 2J \ 16.5 Hz, 2J \ 9.90 Hz), 3.78 (dd, CH P, 1H,
75 61
5 4
HvH
PvH
2
Found: C, 64.86; H, 4.37. IR (cm~1): 1531 (l ). FAB-MS
2J \ 12 Hz), 2.88È1.80 (m, 4 H, CH -dppe). 31PM1HN NMR
CO
[m/z, (%)]: 1297 (10%) [M [ ClO ]`, 1035 (100%) [M
4
PvH
(CDCl ): d 46.61 (d, 1P, PPh -trans-C
ylide
2
, 3J \ 17.6 Hz,
3
2
PvP
[ ClO [ PPh ]`. 1H NMR (CDCl ): d 7.94È6.70 (m, 59 H,
1J \ 3050 Hz), 43.46 (d, 1P, PPh -trans-C , 3J \ 32.9
4
3
3
PvPt
2
aryl
PvP
Ph ] C H ), 3.89 [d, ÈC(H)2P, 1H, 2J \ 26.1 Hz], 3.62 (m,
Hz, 1J \ 1786 Hz), 28.73 (ddd, 1P, PPh in ring, 4J
PvPt
8.5 Hz), 21.13 (d, 1P, CH PPh ). 13CM1HN NMR (CDCl ): d
\
6
4
PvH
2
PvP
CHPt, 1H, 2J
\ 64 Hz). 31PM1HN NMR (CDCl ): d 30.70
PtvH
3
2
3
3
(dd, 1P, PPh in ring, 3J \ 32.7 Hz, 3J \ 17.5 Hz), 26.86
194.57 (dd, CO, 2J \ 10.56 Hz, 2J \ 5.1 Hz), 165.62 (ddd,
2
3
PvP
PvP
PvC
\ 109.6 Hz, 2J
PvC
PcisvC
(t, 1P, PPh -trans-C
, 3J \ 2J \ 17.5 Hz, 1J
\
C , C H , 2J
PtransvC
\ 28.8 Hz, 2J \ 5.9
ylide
PvP PvP PvPt
1
6
4
PvC
2576 Hz), 22.90 (dd, 1P, PPh -trans-C , 1J \ 1698 Hz),
14.37 (s, 1P, CH2PPh ).
Hz), 135È128 (m, Ph ] C H ), 44.82 (td, CH
, 1J
\
3
aryl
PvPt
6
4
ylide
PvC
2J
\ 75.9 Hz, 2J
\ 7.6 Hz), 38.81 (dd, CH P,
3
PtransvC
PvC
PcisvC
2
1J \ 60.2 Hz, 3J \ 9.7 Hz), 28.76 (m, CH -dppe).
PvC
2
[Pt{C H -2-PPh C(H)COC(H)(AuCl)PPh }(dppe)]-
6
4
2
3
(ClO ), 10. To a CH Cl solution (15 mL) of complex 8 (0.074
[Pt{C H -2-PPh C(H)COCH PPh }(phen)](ClO ) , 7. In
4
2 2
6
4
2
2
3
4 2
g, 0.058 mmol) ClAu(tht) (0.018 g, 0.058 mmol) was added and
the resulting solution was stirred at room temperature for 15
min. Evaporation of the solvent to dryness and treatment of
a similar way to that described for 6, 2 (0.21 g, 0.11 mmol)
reacts with AgClO (0.05 g, 0.23 mmol) and phen (0.04 g, 0.23
4
mmol) to give 7 as a white solid. Obtained: 0.23 g (85% yield).
the white residue with Et O (10 mL) gave 10 as a white solid.
Complex 7 was recrystallized from a CH Cl ÈEt O (1 : 10)
2
2
2
2
Obtained: 0.059 g (68% yield). Due to a small amount of
mixture, which gave 7 É CH Cl as white crystals, which were
2
2
decomposition products, complex 10 was recrystallized from
used for analytical and spectroscopic purposes. The amount of
CH Cl Èn-hexane to give white crystals of 10 É 2CH Cl ,
CH Cl was determined by 1H NMR.
2
2
2 2
2
2
which were used for analytical and spectroscopic purposes.
Anal. calcd. for C
H
Cl N O P Pt É CH Cl : C, 50.46;
50 40
2
2
9 2
2 2
Anal. calcd. for C
H, 3.55. Found: C, 48.04; H, 3.87. IR (cm~1): 1621 (l ), 340
H
AuCl O P Pt É 2 CH Cl : C, 48.10,
H, 3.42; N, 2.26. Found: C, 50.61; H, 3.54; N, 2.58. IR
65 55
2
5 4
2 2
(cm~1): 1657 (l ). FAB-MS [m/z, (%)]: 1053 (13%) [M
CO
CO
(l
). FAB-MS [m/z, (%)]: 1403 (35%) [M [ ClO ]` 1170
[ ClO ]`, 952 (100%) [M [ 2 ClO [ H]`. 1H NMR
AuvCl
4
4
4
(15%) [M [ ClO [ AuCl]`. 1H NMR (CDCl ): d 7.90È6.64
(CDCl ): d 10.09 (d, 1H, H , phen, 3J \ 4.5 Hz), 9.24 (d, 1H,
4
6
3
3
a
ab
H , phen, 3J \ 5.1 Hz), 8.70 (d, 1H, H , phen, 3J \ 8.4
a@ a@b@ cb
Hz), 8.56 (d, 1H, H , phen, 3J \ 8.4 Hz), 8.15 (dd, 1H, H ,
c@ c@b@ b@
(m, 49 H, Ph ] C H ), 5.18 (td, CHPt, 1H, 2J \ 3J \ 8
4
PvH
PvH
c
Hz, 3J \ 1.5 Hz, 2J
PvH
\ 55 Hz), 2.77 (s, br, 1H, CHAu),
PtvH
2.52È1.99 (m, 4 H, CH -dppe). 31PM1HN NMR (CDCl ): d
phen), 8.01 (d, 1H, H , phen, 3J \ 9 Hz), 7.99 (dd, 1H, H ,
2
3
d
dd@
b
45.63 (d, 1P, PPh -trans-C
, 3J \ 17.9 Hz, 1J \ 2933
phen), 7.95 (d, 1H, H ), 7.88È7.26 (m, 29 H, Ph), 5.80 (s, 1H,
2
ylide PvP PvPt
d@
Hz), 41.02 (d, 1P, PPh -trans-C , 3J \ 30.5 Hz, 1J
\
CHPt), 5.47 (dd, 1H, CH P, 2J \ 18.00 Hz, 2J \ 12.30
2
aryl
PvP
PvPt
2
HvH
PvH
1856 Hz), 27.98 (ddd, 1P, PPh in ring, 4J \ 13.4 Hz), 25.49
Hz), 5.15 (dd, 1H, CH P, 2J \ 12 Hz). 31PM1HN NMR
2
PvP
2
PvH
(CDCl ): d 26.55 (d, PPh in ring, 4J \ 10 Hz), 20.79 (d,
PvP
[d, 1P, CH(AuCl)PPh ].
3
3
2
CH PPh ).
2
3
[Pt{C H -2-PPh C(H)COC(H)(AuCl)PPh }(PPh ) ]-
6
4
2
3
3 2
(ClO ), 11. Complex 11 was obtained following the same
[Pt{C H -2-PPh C(H)COC(H)2PPh }(dppe)](ClO ),
8.
4
6
4
2
3
4
method as that described for 10: complex 9 (0.108 g, 0.077
mmol) and ClAu(tht) (0.025 g, 0.077 mmol) reacted in CH Cl
To a suspension of 6 (0.20 g, 0.14 mmol) in THF (20 mL) was
added an excess of NaH (0.10 g, 4.16 mmol). This mixture was
stirred at room temperature for 10 h. During this time, a slow
2
2
(10 mL) to give 11 as a white solid. Obtained: 0.086 g (69%
yield). Complex 11 was recrystallized from CH Cl Èn-hexane,
evolution of gas (H ) was observed, and the color of the sus-
2
2
2
giving white crystals of 11 É 0.5 CH Cl , which were used for
pension changed gradually from white to yellow. After the
2
2
analytical and spectroscopic purposes.
reaction time, the suspension was Ðltered and the solution was
evaporated to dryness, extracted with CH Cl (20 mL) and
Ðltered again. The resulting solution was evaporated to
dryness and the oily residue was treated with Et O (15 mL),
giving 8 as a yellow solid. Obtained: 0.11 g (63.9% yield).
Due to the presence of traces of the bis-oxide
Anal. calcd. for
54.25; H, 3.74. Found: C, 54.19; H, 3.86. IR (cm~1): 1631
C
H
AuClO P Pt É 0.5 CH Cl : C,
75 61
5 4
2 2
2
2
(l ), 329 (l
). FAB-MS [m/z, (%)]: 1529 (5%) [M
[ ClO ]`, 1267 (20%) [M [ ClO [ PPh ]`, 1035 (20%)
CO
AuvCl
2
4
4
3
[M [ ClO [ PPh [ AuCl]`. 1H NMR (CDCl ): d 7.79È
4
3
3
6.47 (m, 59 H, Ph ] C H ), 4.55 (t, CHPt, 1H, 3J
\
P(O)Ph CH CH P(O)Ph , complex 8 was recrystallized from
6
4
PvH
2
2
2
2
2J \ 9.3 Hz, 2J
\ 88 Hz), 2.88 (s, br, 1H, CHAu).
CH Cl Èn-hexane to give 8 É 2 CH Cl as yellow crystals,
PvH
PtvH
2
2
2 2
31PM1HN NMR (CDCl ): d 29.61 (ddd, 1P, PPh in ring,
which were used for analytical and spectroscopic purposes.
3
2
3J \ 32.2 Hz, 3J \ 17.7 Hz, 4J \ 10 Hz), 27.12 [d, 1P,
PvP PvP PvP
CH(AuCl)PPh ], 22.51 (t, 1P, PPh -trans-C
Anal. calcd. for C
H
ClO P Pt É 2 CH Cl : C, 55.86; H,
65 55
5 4
2 2
,
3J
\
4.13. Found: C, 56.16; H, 4.84. IR (cm~1): 1529 (l ).
3
3
ylide
PvP
CO
FAB-MS [m/z, (%)]: 1170 (85%) [M [ ClO ]`. 1H NMR
4
2J \ 17.5 Hz, 1J \ 2615 Hz), 19.14 (dd, 1P, PPh -trans-
PvP
aryl
PvPt
, 1J \ 1644 Hz).
PvPt
3
C
(CD Cl ): d 7.91È6.88 (m, 49 H, Ph), 4.15 (t, CHPt, 1H,
2
2
2J \ 3J \ 7.8 Hz, 2J
PvH PvH PtvH
2J \ 25.2 Hz], 2.47È1.82 (m, 4 H, CH -dppe). 31PM1HN
PvH
NMR (CD Cl ): d 45.28 (d, 1P, PPh -trans C
\ 69 Hz), 3.09 [d, ÈC(H)2P, 1H,
Acknowledgements
Funding by the Direccion General de Ensenanza Superior
(Spain, project PB98-1595-C02-01) is gratefully acknowledged,
2
, 3J
\
2
2
2
ylide
17.7 Hz, 1J \ 2688 Hz), 44.41 (d, 1P, PPh -trans-C
PvPt
PvP
,
2
aryl
New J. Chem., 2000, 24, 623È630
629

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22 M. L. Illingsworth, J. A. Teagle, J. L. Burmeister, W. C. Fultz and
A. L. Rheingold, Organometallics, 1983, 2, 1364.
23 J. A. Teagle and J. L. Burmeister, Inorg. Chim. Acta, 1986, 118,
65.
and we thank Professor J. Fornies for invaluable logistical
support.
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New J. Chem., 2000, 24, 623È630