Transformation of μ4-phosphinidenes at an Ru5 center: Isolation and structural characterization of hydroxyphosphinidene cluster acids, fluorophosphinidenes, and a novel μ5-phosphide

Article abstract of DOI:10.1021/ic040077e

Acid hydrolysis of [Ru₅(CO)₁₅(μ₄- PNⁱPr₂)] (2) or protonation of the anionic PO cluster [Ru₅(CO)₁₅(μ₄-PO)]^- (3) affords the hydroxyphosphinidene complex [Ru₅(CO) ₁₅(μ₄-POH)]·1·[H₂N ⁱPr₂][CF₃SO₃], which cocrystallizes with a hydrogen-bonded ammonium triflate salt. Reaction of [Ru ₅(CO)₁₅(μ₄-PNⁱPr₂)] (2) with bis(diphenylphosphino)methane (dppm) leads to [Ru₅(CO) ₁₃(μ-dppm)(μ₄-PNⁱPr₂)] (4). Acid hydrolysis of 4 leads to the dppm-substituted hydroxyphosphinidene [Ru ₅(CO)₁₃(μ-dppm)(μ₄-POH)] (5), which is analogous to 1, but unlike 1, can be readily isolated as the free hydroxyphosphinidene acid. Compound 5 can also be formed by reaction of 3 with dppm and acid. The cationic hydride cluster [Ru₅(CO) ₁₃(μ-dppm)(μ₃-H)(μ₄-POH)][CF ₃SO₃] (6) can be isolated from the same reaction if chromatography is not used. Compound 4 also reacts with HBF₄ to form the fluorophosphinidene cluster [Ru₅(CO)₁₃(μ-dppm) (μ₄-PF)] (7), while reaction with HCl leads to the μ-chloro, μ₅-phosphide cluster [Ru₅(CO)₁₃(μ-dppm) (μ-Cl)(μ₅-P)] (8).

Full text of DOI:10.1021/ic040077e

Inorg. Chem. 2005, 44, 2766−2773
Transformation of
Structural Characterization of Hydroxyphosphinidene Cluster Acids,
Fluorophosphinidenes, and a Novel 5-Phosphide
µ4-Phosphinidenes at an Ru5 Center: Isolation and
µ
Ludmila Scoles,†,‡ Brian T. Sterenberg,†,§ Konstantin A. Udachin,† and Arthur J. Carty*,†,‡
Steacie Institute for Molecular Sciences, National Research Council Canada, 100 Sussex DriVe,
Ottawa, Ontario, Canada K1A 0R6, the Ottawa-Carleton Chemistry Research Institute,
Department of Chemistry, UniVersity of Ottawa, Ottawa, Ontario, Canada K1N 6N5,
and the Department of Chemistry and Biochemistry, UniVersity of Regina,
Regina, Saskatchewan, Canada S4S 0A2
Received June 9, 2004
Acid hydrolysis of [Ru5(CO)15(
the hydroxyphosphinidene complex [Ru5(CO)15(
bonded ammonium triflate salt. Reaction of [Ru5(CO)15
leads to [Ru5(CO)13( -dppm)(
4-PNiPr2)] (4). Acid hydrolysis of 4 leads to the dppm-substituted hydroxyphosphinidene
[Ru5(CO)13 -dppm)( 4-POH)] (5), which is analogous to 1, but unlike 1, can be readily isolated as the free
hydroxyphosphinidene acid. Compound 5 can also be formed by reaction of 3 with dppm and acid. The cationic
hydride cluster [Ru5(CO)13 -dppm)( 3-H)( 4-POH)][CF3SO3] (6) can be isolated from the same reaction if
chromatography is not used. Compound 4 also reacts with HBF4 to form the fluorophosphinidene cluster [Ru5(CO)13(
dppm)( 4-PF)] (7), while reaction with HCl leads to the -chloro, 5-phosphide cluster [Ru5(CO)13 -dppm)(
5-P)] (8).
µ
4-PNiPr2)] (2) or protonation of the anionic PO cluster [Ru5(CO)15(
4-POH)]
[H2NiPr2][CF3SO3], which cocrystallizes with a hydrogen-
4-PNiPr2)] (2) with bis(diphenylphosphino)methane (dppm)
µ
4-PO)]- (3) affords
µ
‚1‚
µ
(
µ
µ
(
µ
µ
(µ
µ
µ
µ-
µ
µ
µ
(µ
µ-
Cl)(
µ
Introduction
design of a versatile route to phosphorus monoxide (PO)
complexes via the acid-catalyzed hydrolysis of P-N bonds
in coordinated aminophosphinidenes.6-9 The Ru5(µ4-PR)
clusters have provided a particularly versatile platform for
studying the transformations of these ligands, and examples
of Ru5 aminophosphinidenes, fluorophosphinidenes, and
phosphorus monoxide clusters have been described.8,10 The
Ru5 clusters have also been used to form mixed nitrosyl/
phosphinidene complexes, allowing us to compare the
transformations of phosphorus and nitrogen ligands in the
same cluster.11
Phosphinidenes (PR) are important and versatile ligands
in organometallic chemistry.1 The PR group is a powerful
polynucleating ligand in metal cluster chemistry that en-
hances structural integrity and stability through µ3- and µ4-
face capping coordination.2 Although cluster-bound phos-
phinidenes are often inert and used as structural elements,
heteroatom-substituted phosphinidenes in clusters can show
reactivity at phosphorus.3-9
Over the past several years, we have developed an
extensive chemistry based on the transformation of func-
tionalized phosphinidenes on metal clusters,4,5 including the
(4) Wang, W.; Corrigan, J. F.; Enright, G. D.; Taylor, N. J.; Carty, A. J.
Organometallics 1998, 17, 427.
(5) Wang, W.; Enright, G. D.; Driediger, J.; Carty, A. J. J. Organomet.
Chem. 1997, 541, 461.
* Author to whom correspondence should be addressed. E-mail:
acarty@pco-bcp.gc.ca.
(6) Corrigan, J. F.; Doherty, S.; Taylor, N. J.; Carty, A. J. J. Am. Chem.
Soc. 1994, 116, 9799. Wang, W.; Corrigan, J. F.; Doherty, S.; Enright,
G. D.; Taylor, N. J.; Carty, A. J. Organometallics 1996, 15, 2770.
Sterenberg, B. T.; Scoles, L.; Carty, A. J. Coord. Chem. ReV. 2002,
231, 183-197.
(7) Wang, W.; Carty, A. J. New J. Chem. 1997, 21, 773.
(8) Yamamoto, J. H.; Udachin, K. A.; Enright, G. D.; Carty, A. J. Chem.
Commun. 1998, 2259.
(9) Scoles, L.; Yamamoto, J. H.; Brissieux, L.; Sterenberg, B. T.; Udachin,
K. A.; Carty, A. J. Inorg. Chem. 2001, 40, 6731-6736.
(10) Yamamoto, J. H.; Scoles, L.; Udachin, K. A.; Enright, G. D.; Carty,
A. J. J. Organomet. Chem. 2000, 600, 84.
† National Research Council Canada.
‡ University of Ottawa.
§ University of Regina.
(1) Fehlner, T. P. Inorganometallic Chemistry; Plenum Press: New York,
1992. Dillon, K. B.; Mathey, F.; Nixon, J. F. Phosphorus: The Carbon
Copy; John Wiley & Sons, Ltd.: Chichester, U.K., 1998.
(2) Huttner, G.; Knoll, K. Angew. Chem., Int. Ed. Engl. 1987, 26, 743.
(3) Jordan, M. R.; White, P. S.; Schauer, C. K.; Mosley, M. A., III. J.
Am. Chem. Soc. 1995, 117, 5403. Borg-Breen, C. C.; Bautista, M. T.;
Schauer, C. K.; White, P. S. J. Am. Chem. Soc. 2000, 122, 3952. Wang,
W.; Enright, G. D.; Carty, A. J. J. Am. Chem. Soc. 1997, 119, 12370.
2766 Inorganic Chemistry, Vol. 44, No. 8, 2005
10.1021/ic040077e CCC: $30.25
© 2005 American Chemical Society
Published on Web 03/12/2005

Transformation of µ4-Phosphinidines at an Ru5 Center
Scheme 1
One particularly interesting but poorly documented class
of face capping µ-PR ligands is that where the functional
group R is OH, namely the hydroxyphosphinidenes. With a
single µ3- or µ4-POH group bound to a π-acidic Mn(CO)m
cluster core and by analogy to inorganic hydroxyphosphorus
compounds, such molecules might be expected to exhibit
strongly acidic properties. To date, few such organometallic
cluster acids have been characterized, examples being limited
to the tetranuclear cluster Ru4(CO)13(µ3-POH)5 and a bi-
nuclear rhenium complex bearing a µ2-POH group.12
In this paper, we describe the synthesis of the µ4-
hydroxyphosphinidene cluster [Ru5(CO)15(µ4-POH)] 1 via the
acid catalyzed hydrolysis of [Ru5(CO)15(µ4-PNiPr2)] 2 and
the structure of the strongly hydrogen-bonded association
product 1[H2NiPr2][CF3SO3]. In an effort to modify the
reactivity of 2, we have explored the effect of phosphine
substitution at the Ru5 core to increase the overall cluster
electron density and, hence, reduce the acidity of the µ4-
POH group. The success of this strategy is shown by the
isolation and structural characterization of [Ru5(CO)13(µ-
dppm)(µ4-POH)], a molecule that contains a non-hydrogen-
bonded µ-POH group [dppm ) bis(diphenylphosphino)-
methane].
Figure 1. ORTEP diagram of [Ru5(CO)15(µ4-POH)]‚1‚[H2NiPr2][CF3SO3],
showing the hydrogen bonding between the POH ligand and the cocrys-
tallized triflate anions. Thermal ellipsoids are shown at the 50% level. The
[H2NiPr2]+ counterion has been omitted for clarity.
Table 1. Selected Distances and Angles in [Ru5(CO)15(µ4-POH)]
1‚[H2NiPr2][CF3SO3]
P(1)-O(16)
Ru(1)-P(1)
Ru(2)-P(1)
Ru(3)-P(1)
Ru(4)-P(1)
Ru(1)-Ru(2)
Ru(1)-Ru(4)
1.590(2)
Ru(1)-Ru(5)
Ru(2)-Ru(3)
Ru(2)-Ru(5)
Ru(3)-Ru(4)
Ru(3)-Ru(5)
Ru(4)-Ru(5)
O(16)-O(97)
2.7769(3)
2.8813(3)
2.8334(3)
2.8727(3)
2.8386(3)
2.8502(3)
2.639(3)
2.3657(7)
2.3247(7)
2.3462(7)
2.3160(7)
2.9356(3)
2.8836(3)
O(16)-H(1)-O(97)
177(5)
hydrogen bonding.13 In the related POH cluster [Ru4(CO)13-
(µ3-POH)],5 the solid state structure shows hydrogen bonding
to a second molecule of the cluster. This type of interaction
is probably less favorable in 1 because of steric interactions
between the cluster carbonyl ligands. The P-O distance of
1.590(2) Å is longer than the P-O distance in the related
phosphorus monoxide cluster [H2NCy2][Ru5(CO)15(µ4-PO)]8
of 1.516(4) Å, which is expected upon protonation of the
PO ligand. The core cluster is analogous to several other
Ru5 PR structures previously described8,10 and consists of
five ruthenium atoms arranged in a square-based pyramid.
The square base is capped by the phosphorus atom of the
POH ligand, resulting in an octahedral arrangement of the
core cluster atoms. Each ruthenium atom is bound to three
carbonyl ligands. The resulting cluster valence electron count
is 74, and with eight metal-metal bonds, the cluster is
electron precise. The entire Ru5P framework contains seven
skeletal electron pairs, consistent with a closo M5E structure.
The difficulty in isolating the “free”, non-hydrogen-
bonded hydroxyphosphinidene cluster in the solid state and
Results and Discussion
In our studies on the transformations of substituted PR
ligands on Ru5 clusters, one species that has thus far eluded
isolation is the hydroxyphosphinidene [Ru5(CO)15(µ4-POH)]
(1), which is a plausible intermediate in the transformation
of [Ru5(CO)15(µ4-PNiPr2)] (2) into the anionic PO complex
[H2NiPr2][Ru5(CO)15(µ4-PO)] (3) (Scheme 1). The compound
[Ru5(CO)15(µ4-POH)] (1) can be readily prepared in solution,
either by protonation of [M][Ru5(CO)15(µ4-PO)] (3; M )
H2NiPr2 or K) or by hydrolysis of [Ru5(CO)15(µ4-PNiPr2)]
in the presence of excess acid. However, attempts to
crystallize free 1 failed, always resulting in either deproto-
nation to form 3 or cocrystallization with and hydrogen
bonding to a salt. The structure of 1 cocrystallized with the
diisopropylammonium triflate salt [H2NiPr2][CF3SO3] is
shown in Figure 1. Selected distances and angles are given
in Table 1. The structure reveals hydrogen bonding between
the POH ligand and the oxygen of the triflate anion. A peak
for the hydrogen atom was located in a difference Fourier
map. The O(16)‚‚‚O(97) distance of 2.639(3) Å, along with
a nearly linear O-H‚‚‚O angle [177(5)°], indicates substantial
1
the failure to observe an H NMR resonance for the POH
ligand in solution even at low temperatures, which is
probably due to rapid proton exchange, suggests that the
unassociated cluster [Ru5(CO)15(µ4-POH)] is acidic and that
hydrogen bonding to the ammonium salt persists in solution.
Ready deprotonation of 1 in solution by weak bases such as
HNiPr2 to afford 3 confirms this acidity. The structure of
(11) Scoles, L.; Sterenberg, B. T.; Udachin, K. A.; Carty, A. J. Chem.
Commun. 2002, 320-321. Scoles, L.; Sterenberg, B. T.; Udachin, K.
A.; Carty, A. J. Can. J. Chem. 2002, 80, 1538-1545.
(12) Ehses, M.; Schmitt, G.; Wolmersha¨user, G.; Scherer, O. J. Z. Anorg.
Allg. Chem. 1999, 625, 382.
(13) Taylor, R.; Kennard, O. Acc. Chem. Res. 1984, 17, 320-326.
Inorganic Chemistry, Vol. 44, No. 8, 2005 2767

Scoles et al.
Scheme 2
1‚[H2NiPr2][CF3SO3] (Figure 1) provides a ready explanation
for the acid character. The µ4-POH group is coordinated to
four of the five ruthenium fragments in the cluster core, each
of which possesses three strong π-acidic CO ligands, which
serve to reduce the electron density at the ruthenium centers.
The Ru5(CO)15 core is, thus, strongly electron withdrawing
toward the POH ligand, rendering the O-H group more
acidic. One strategy to reduce this acidity would be to
substitute π-acid CO groups on the Ru5(CO)15 cluster core
with electron donating phosphine ligands. However, to access
phosphine substitution products of 1, without deprotonating
the POH group by the phosphines, it was necessary to
approach the problem indirectly, using the aminophosphin-
idene complex 2 as a precursor.
given in Table 1. The core of the structure consists of five
ruthenium atoms arranged in a square-based pyramid with
the square face capped by the µ4-PNiPr2 ligand. The structure
of 4 is similar to that of 2 and has the same electron count.
The diphosphine ligand bridges one edge of the square base,
replacing two carbonyl ligands, and is directed away from
the aminophosphinidene ligand toward the apical Ru(CO)3
group. Each of the phosphine-bound ruthenium atoms has
two additional carbonyl ligands, whereas the other three
ruthenium centers have three each. The aminophosphinidene
ligand is arranged such that the PNC2 plane bisects the Ru4
square approximately parallel to the Ru(1)-Ru(4) and
Ru(2)-Ru(3) metal-metal bonds, rather than bisecting the
square diagonally, which is more typical of µ4-aminophos-
phinidenes.14 This difference is likely due to the need to avoid
steric interactions with the apical CO groups of Ru(1) and
Ru(2) as well as with the phenyl substituents of the
diphosphine. The P(1)-N(1) distance of 1.688(4) Å is similar
to those observed in related µ4-aminophosphinidenes9-11,14
and is somewhat shorter than a typical P-N single bond,15
indicating partial multiple P-N bonding.
The complex [Ru5(CO)15(µ4-PNiPr2)] (2) reacts with bis-
(diphenylphosphino)methane (Ph2PCH2PPh2, dppm), to form
[Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4) (Scheme 2). Compound
4 has been structurally characterized. An ORTEP diagram
is shown in Figure 2, and selected distances and angles are
The 31P NMR spectrum of 4 consists of a triplet at δ 500
that corresponds to the aminophosphinidene ligand and a
doublet at δ 32 corresponding to the dppm ligand. The P-P
1
coupling constant is 38 Hz. The H NMR spectrum shows
the expected peaks for dppm phenyl groups and two
inequivalent methylene hydrogen atoms, as expected based
upon the symmetry of the complex. The two isopropyl groups
of the PNiPr2 ligand are equivalent in the 1H NMR spectrum
and appear as a septet at δ 4.3 and a doublet at δ 1.4. The
IR spectrum shows bands for terminal carbonyl ligands at
2064, 2029, and 2011 cm-1.
Acid hydrolysis of [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4)
with triflic acid, followed by thin-layer chromatography,
leads to [Ru5(CO)13(µ-dppm)(µ4-POH)] (5). In contrast to
(14) Kahlal, S.; Udachin, K. A.; Scoles, L.; Carty, A. J.; Saillard, J.-Y.
Organometallics 2000, 19, 2251.
(15) Orpen, A. G.; Brammer, L.; Allen, F. H.; Kennard, O.; Watson, D.
G.; Taylor, R. J. Chem. Soc., Dalton Trans. 1989, S1.
Figure 2. ORTEP diagram of [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4).
Thermal ellipsoids are shown at the 50% level, and the hydrogen atoms
have been omitted.
2768 Inorganic Chemistry, Vol. 44, No. 8, 2005

Transformation of µ4-Phosphinidines at an Ru5 Center
Figure 4. ORTEP diagram of [Ru5(CO)13(µ-dppm)(µ3-H)(µ4-POH)]-
[CF3SO3] (6), showing the hydrogen bonding between the POH ligand and
the triflate counterion. Thermal ellipsoids are shown at the 50% level, and
the hydrogen atoms of the dppm ligand have been omitted.
Figure 3. ORTEP diagram of [Ru5(CO)13(µ-dppm)(µ4-POH)] (5). Thermal
ellipsoids are shown at the 50% level, and the hydrogen atoms on the dppm
ligand have been omitted.
1
in the H NMR spectrum, which shows only the expected
peaks for the dppm phenyl and methylene groups.
[Ru5(CO)15(µ4-POH)] (1), the cluster 5 can readily be isolated
free of diisopropylammonium triflate. The ORTEP diagram
of the crystal structure is shown in Figure 3. The core
structure is the same as that of 1‚[H2NiPr2][CF3SO3] with
the POH ligand capping the square face of a square-based
pyramid of ruthenium atoms. The P-O distance of 1.632(2)
Å in 4 is slightly longer than that in 1‚[H2NiPr2][CF3SO3]
[1.590(2) Å], in which the POH group is hydrogen bonded.
This bond-length difference can be attributed to the absence
of hydrogen bonding in 5, but it might also be influenced
by the change in cluster electron density that results from
replacing two carbonyl groups with dppm. The POH
hydrogen atom was located in the Fourier map. In contrast
to 4, the dppm ligand in 5 is positioned well out of the
equatorial plane on the same side of the Ru4 unit as the
hydroxyphosphinidene unit, while carbonyl ligands occupy
the equatorial positions. This arrangement reflects the much
smaller steric size of POH compared to that of the Ru(CO)3
unit on the opposite face and minimizes steric interaction
between the dppm and the carbonyl ligands. In contrast, the
larger aminophosphinidene ligand in 4 forces the dppm
ligand to adopt a more equatorial position. Compound 5 can
also be formed by direct reaction of [K][Ru5(CO)15(µ4-PO)]
(3) with dppm and triflic acid.
The 31P NMR spectrum of the POH cluster 5 shows a
triplet at δ 503 for the hydroxyphosphinidene ligand and a
doublet δ 25.1 for the dppm ligand. The P-P coupling
constant of 11 Hz is smaller than that in 4, reflecting the
relative cis arrangement of the phosphorus ligands in 5.16
The P-Ru-P angles in 5 are 92.60(3)° and 93.10(3)°. In 4,
the relationship between the two types of phosphorus ligands
is closer to trans with P-Ru-P angles of 138.05(5)°and
131.92(5)°, and the P-P coupling constant is correspondingly
larger. No peak for the POH hydrogen in 5 could be located
The acidity of [Ru5(CO)13(µ-dppm)(µ4-POH)] (5) was
measured using an acid-base equilibrium with PCy3 as the
base. Equilibrium concentrations were measured using 31P
NMR.17 The pKa value for 5 is 9.5 ( 0.5 (aqueous scale),
similar to that of phenol (pKa ) 10.0). A comparable
organometallic acid is the hydride complex [Ru(H)2Cp(dmpe)]
(pKa ) 9.3).18 These results confirm that the hydroxyphos-
phinidene cluster 5 is a moderately strong acid, although it
is weaker than inorganic phosphorus acids such as H3PO4.
In the absence of a chromatographic workup, a different
cluster [Ru5(CO)13(µ-dppm)(µ3-H)(µ4-POH)][OSO2CF3] (6)
can be isolated from the above reactions. The 31P NMR
spectrum showed a peak at δ 497, in the expected region
1
for a POH ligand. The H NMR showed peaks attributable
to the dppm ligand and a metal hydride that appears at δ
-18 as a broad singlet. At -80 °C, an additional peak also
appears at δ 10.4 that can be assigned to the POH ligand.
An ORTEP diagram of the cation is shown in Figure 4. The
core of the cluster is the same as that of 5, with a square-
based pyramid of ruthenium atoms capped on the square face
with a POH ligand. The POH hydrogen was located in the
Fourier map and then placed in an idealized position but
allowed to rotate freely about the PO bond. Its final position,
and the position of the triflate counterion, clearly indicates
the presence of hydrogen bonding between it and the triflate
anion. In contrast to that in 5, the dppm ligand in 6 occupies
the equatorial position. This arrangement is necessary to
accommodate the hydrogen bonding to the counterion. The
hydride ligand was readily located in the Fourier map and
bridges the triangular face of the square-based pyramid
immediately adjacent to the bridging dppm ligand. The PO
distance of 1.606(3) Å is, as expected, shorter than that in 5
and similar to that in 1‚[H2NiPr2][CF3SO3].
(16) Jameson, C. J. In Phosphorus-31 NMR Spectroscopy in Stereochemical
Analysis; Verkade, J. G., Quin, L. D., Eds.; VCH: Deerfield Beach,
FL, 1987.
(17) Jessop, P. J.; Morris, R. H. Coord. Chem. ReV. 1992, 121, 155-284.
(18) Chinn, M. S.; Heinekey, D. M. J. Am. Chem. Soc. 1987, 109, 5865-
5867.
Inorganic Chemistry, Vol. 44, No. 8, 2005 2769

Scoles et al.
Figure 5. ORTEP diagram of [Ru5(CO)13(µ-dppm)(µ4-PF)] (7). Thermal
ellipsoids are shown at the 50% level, and the hydrogen atoms have been
omitted.
Figure 6. ORTEP diagram of [Ru5(CO)13(µ-dppm)(µ-Cl)(µ5-P)] (8).
Thermal ellipsoids are shown at the 50% level, and the hydrogen atoms
have been omitted.
Table 2. Selected Distances in [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4),
[Ru5(CO)13(µ-dppm)(µ4-POH)] (5),
[Ru5(CO)13(µ-dppm)(µ3-H)(µ4-POH)][OSO2CF3] (6), and
[Ru5(CO)13(µ-dppm)(µ4-PF)] (7)
of the 19F spectrum is masked by the broadness of the peaks
in the 31P spectrum.
The X-ray structure of 7 (Figure 5 and Table 2) reveals
that the structure is analogous to those of 4 and 5. In 7, the
dppm ligand adopts a conformation similar to that observed
in 5, in which the ligand is above the equatorial plane on
the same side as the µ4-PF ligand. This arrangement reflects
the similar size of the PF and POH groups. A comparison
of the Ru-P distances to those of the µ4-phosphinidene
ligands (Table 2) shows that increasing the electronegativity
of the substituent leads to shorter M-P bonds. This change
can be attributed to an increase in metal to phosphorus π
back bonding as the electronegativity of the phosphorus
substituent increases.9
4
5
6
7
P(1)-N(1)
1.688(4)
P(1)-O(14)
P(1)-F(1)
1.632(2)
1.606(3)
1.621(2)
Ru(1)-P(1)
Ru(2)-P(1)
Ru(3)-P(1)
Ru(4)-P(1)
Ru(1)-P(2
Ru(2)-P(3)
Ru(1)-Ru(2)
Ru(1)-Ru(4)
Ru(2)-Ru(3)
Ru(3)-Ru(4
Ru(1)-Ru(5)
Ru(2)-Ru(5)
Ru(3)-Ru(5)
Ru(4)-Ru(5)
2.384(1)
2.356(1)
2.424(1)
2.381(1)
2.332(1)
2.355(1)
2.3417(7) 2.3614(11) 2.303(1)
2.3346(7) 2.3524(11) 2.322(1)
2.3523(8) 2.3297(11) 2.306(1)
2.3583(8) 2.3433(11) 2.329(1)
2.3088(8) 2.3356(11) 2.307(1)
2.2970(8) 2.3433(11) 2.2934(9)
2.9428(6) 2.8784(3) 2.9457(5)
2.8578(6) 2.8965(3) 2.9057(5)
2.8389(6) 2.9221(3) 2.9201(5)
2.8876(6) 2.9218(3) 2.9080(5)
2.8656(6) 2.8926(3) 2.9281(5)
2.9185(6) 2.8462(3) 2.9631(5)
2.8112(6) 2.8092(3) 2.8353(5)
2.8742(6) 2.7879(3) 2.8625(5)
2.8796(4)
2.9435(4)
2.9138(4)
2.9648(5)
2.8538(4)
2.8538(4)
2.8143(4)
2.7875(5)
In contrast to the reaction with HBF4‚Et2O, HCl addition
led to the µ-chloro, µ5-phosphide cluster [Ru5(CO)13(µ-
dppm)(µ-Cl)(µ5-P)] (8). The ORTEP diagram of 8 is shown
in Figure 6. Selected distances and angles are given in Table
3. The structure consists of four ruthenium atoms arranged
in a square, with the fifth ruthenium atom bridging one edge
of the square. The angle between the square and the triangle
thus formed is 84.07(1)°. The phosphide atom bridges all
five ruthenium atoms, forming a nearly symmetrical interac-
tion with the four atoms of the square (Ru-P ) 2.363, 2.321,
2.313, and 2.345 Å). The distance to the fifth Ru atom is
slightly shorter at 2.233 Å. The chloro ligand bridges the
opposite edge of the square from the fifth ruthenium atom
on the opposite side of the square. The dppm ligand bridges
the same edge as the chloride in the equatorial plane of the
ruthenium square. In addition to bridging the chloro and
dppm groups, these two ruthenium atoms each have two
terminal carbonyl ligands, while the other three ruthenium
atoms have three terminal carbonyls each. The resulting
electron count is 78, with the phosphide contributing all of
its five valence electrons and the bridging chloride function-
ing as a three-electron donor. The higher electron count
compared to that of the µ4-phosphinidene clusters results in
P(1)-Ru(1)-P(2) 138.05(5) 92.60(3)
P(1)-Ru(2)-P(3) 131.92(5) 93.10(3)
127.25(4)
128.80(4)
91.52(3)
89.40(3)
The hydrolysis of [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4) has
also been investigated with other acids. Reaction with HBF4
(with or without water present) leads to the fluorophosphin-
idene cluster [Ru5(CO)13(µ-dppm)(µ4-PF)] (7), effectively
cleaving the P-N bond with HF. This reactivity is consistent
with that seen in the reactions of [Ru4(CO)13(µ3-PNiPr2)] and
[Ru5(CO)15(µ4-PNiPr2)] (2) with HBF4‚Et2O.7,10 Compound
7 can be readily characterized by IR and NMR. The PF
ligand appears in the 19F NMR spectrum as a doublet of
triplets at δ 8.7, showing a large one-bond P-F coupling
constant of 1076 Hz, as well as a long-range coupling
constant of 20 Hz to the dppm phosphorus atoms. In the 31
P
NMR spectrum, the PF ligand appears as a doublet of triplets
at δ 539, showing the large one-bond P-F coupling constant,
as well as a long-range P-P coupling constant of 31 Hz.
The resonance for the dppm ligand appears at δ 28.5 as a
doublet. The long-range P-F coupling expected on the basis
2770 Inorganic Chemistry, Vol. 44, No. 8, 2005

Transformation of µ4-Phosphinidines at an Ru5 Center
Table 3. Selected Distances and Angles in
[Ru5(CO)13(µ-dppm)(µ-Cl)(µ5-P)] (8)
tion have been described. Triply and quadruply bridging
phosphide ligands are also relatively common.29
Ru(1)-P(1)
Ru(2)-P(1)
Ru(3)-P(1
Ru(4)-P(1)
Ru(5)-P(1)
Ru(1)-Cl(1)
Ru(2)-Cl(1
Ru(1)-P(2)
2.3455(6) Ru(2)-P(3)
2.3634(6) Ru(1)-Ru(2)
2.3208(7) Ru(1)-Ru(4)
2.3129(7) Ru(2)-Ru(3)
2.2333(6) Ru(3)-Ru(4)
2.4491(6) Ru(3)-Ru(5)
2.4342(6) Ru(4)-Ru(5)
2.3451(7)
2.4107(7)
2.8738(3)
3.0019(3)
3.0147(3)
2.9230(3)
2.8878(3)
2.8767(3)
The difference between HCl and HF addition can be
attributed to the nature of the base. The softer chloride anion
coordinates to the metals, while the harder fluoride binds
preferentially to phosphorus. The dppm ligand seems to be
important in maintaining cluster integrity in the formation
of 8. Reactions of analogous aminophosphinidene clusters
without dppm with HCl led to cluster fragmentation.
P(2)-Ru(1)-P(1)
P(1)-Ru(2)-P(3)
P(1)-Ru(1)-Cl(1)
P(1)-Ru(2)-Cl(1)
P(2)-Ru(1)-Cl(1)
P(3)-Ru(2)-Cl(1)
Ru(5)-P(1)-Ru(4)
Ru(5)-P(1)-Ru(3)
Ru(4)-P(1)-Ru(3)
131.25(2)
Ru(4)-P(1)-Ru(2)
Ru(3)-P(1)-Ru(2)
Ru(1)-P(1)-Ru(2)
Ru(2)-Cl(1)-Ru(1)
Ru(4)-Ru(5)-Ru(3)
Ru(3)-Ru(4)-Ru(1)
Ru(2)-Ru(1)-Ru(4)
Ru(1)-Ru(2)-Ru(3)
Ru(5)-Ru(3)-Ru(4)
Ru(5)-Ru(3)-Ru(2)
Ru(4)-Ru(3)-Ru(2)
Ru(5)-Ru(4)-Ru(3)
Ru(5)-Ru(4)-Ru(1)
125.35(3)
80.12(2)
140.86(2)
88.41(2)
88.35(2)
90.56(2)
84.23(2)
78.49(2)
78.68(2)
78.22(2)
Conclusion
75.221(19)
72.100(17)
60.937(7)
90.235(8)
89.969(8)
90.924(8)
59.344(8)
95.355(8)
88.792(8)
59.719(7)
94.321(8)
Replacement of π-acceptor carbonyl ligands with a donor
phosphine ligand results in a reduction of the acidity of the
µ4-POH ligand. The sensitivity of this ligand to the overall
cluster density is not surprising given that the phosphorus
atom forms an integral part of the cluster core. The alteration
of cluster electron density has allowed the isolation of the
targeted µ4-POH cluster [Ru5(CO)13(µ-dppm)(µ4-POH)]. The
presence of the chelating diphosphine ligand also enhances
cluster integrity. A novel example of a µ-chloro, µ5-
phosphide cluster Ru5(CO)13(µ-dppm)(µ-Cl)(µ5-P) has also
been characterized.
Ru(5)-P(1)-Ru(1) 140.63(3)
Ru(4)-P(1)-Ru(1)
80.24(2)
Ru(3)-P(1)-Ru(1) 128.25(3)
Ru(5)-P(1)-Ru(2) 143.45(3)
the more open structure observed for 8 and two fewer Ru-
Ru bonds.
The 31P NMR spectrum of 8 shows a triplet for the
phosphide ligand at δ 803. A doublet at δ 28 corresponds to
the dppm ligand. The P-P coupling constant of 52 Hz is
substantially higher than in any of the other complexes and
reflects the transoid arrangement of the phosphide and
phosphine ligands in 8. The extreme low-field shift of the
phosphide resonance is not unusual for semiencapsulated
phosphide ligands.19,20
Experimental Section
General Comments. Reactions were carried out under an
atmosphere of dry nitrogen. Dichloromethane and hexane were
appropriately dried before use. The reagents bis(diphenylphos-
phino)methane, triflic acid, tetrafluoroboric acid, and hydrochloric
acid were purchased from Strem Chemicals and Aldrich and used
without any further purification. The compounds [Ru5(CO)15(µ4-
PNiPr2)] and [K][Ru5(CO)15(µ4-PO)] were synthesized by known
procedures.10 Preparative thin-layer chromatography was carried
The semiencapsulated µ5 coordination of the phosphide
atom in 8 appears to be quite unusual. Only two five-
coordinate phosphide clusters of group 8 metals have
previously been described, one of ruthenium21 and another
of iron.22 In addition, a gold cluster,23 a nickel cluster,24 and
mixed iron-gold clusters25 with µ5-P ligands are known. The
coordination mode of the phosphorus atom in 8, which caps
a square of ruthenium atoms and forms an additional bond
with the fifth, edge-bridging ruthenium atom, appears to be
unique. The previous Ru and Fe complexes contain a more
open geometry in which the phosphorus atom bridges a
triangle of metal atoms and forms additional bonds to two
other metal atoms, which are connected in a chain to the
triangle by single metal-metal bonds. In both of these cases,
the interaction with one of the five metals is substantially
weaker. Coordination of a bare phosphorus atom to six
transition metals is much more common, and several
examples of Ru,20,26 Os,27 and Co19,28 µ6-phosphide coordina-
1
out using silica gel plates (60 A F254) (Merck, 0.25 mm). The H
and 31P NMR spectra were recorded on a Bruker DRX-400
spectrometer. Elemental analyses were carried out by Guelph
Chemical Laboratories, Guelph, Ontario, Canada.
Preparation of Compounds. a. Synthesis of [Ru5(CO)15(µ4-
POH)]‚1‚[H2NiPr2][CF3SO3]. To a green solution of [Ru5(CO)15-
(µ4-PNiPr2)] (2; 120 mg, 0.113 mmol) in CH2Cl2 (10 mL) was added
triflic acid CF3SO3H (120 µL) and H2O (120 µL). The reaction
flask was briefly evacuated, refilled with nitrogen, and then heated
under reflux for 18 h. The reaction mixture was dried over
magnesium sulfate and filtered. The solvent was removed and the
residue was redissolved in CH2Cl2 (2 mL), layered with hexane (2
mL), and cooled to -30 °C for 2 days, resulting in the formation
of crystals of [Ru5(CO)15(µ4-POH)][H2NiPr2][CF3SO3]. Yield: 90
mg, 70%. IR (CH2Cl2, ν CO, cm-1): 2058 s, 2028 m. 31P{1H}
NMR (CDCl3): δ 520. 1H NMR (CDCl3): δ 3.4 [sept., 3J(HH) )
(26) Frediani, P.; Bianchi, M.; Salvini, A.; Piacenti, F.; Ianelli, S.; Nardelli,
M. J. Chem. Soc., Dalton Trans. 1990, 1705. Frediani, P.; Bianchi,
M.; Salvini, A.; Piacenti, F.; Ianelli, S.; Nardelli, M. J. Chem. Soc.,
Dalton Trans. 1990, 165.
(27) Colbran, S. B.; Housecroft, C. E.; Johnson, B. F. G.; Lewis, J.; Owen,
S. M.; Raithby, P. R. Polyhedron 1988, 7, 1759-1765. Colbran, S.
B.; Lahoz, F. J.; Raithby, P. R.; Lewis, J.; Johnson, B. F. G.; Cardin,
C. J. J. Chem. Soc., Dalton Trans. 1988, 173. Colbran, S. B.; Hay, C.
M.; Johnson, B. F. G.; Lahoz, F. J.; Lewis, J.; Raithby, P. R. J. Chem.
Soc., Chem. Commun. 1986, 1766.
(28) Chini, P.; Ciani, G.; Martinengo, S.; Sironi, A. J. Chem. Soc., Chem.
Commun. 1979, 188. Hu, X.; Liu, Q.-W.; Liu, S.-T.; Zhang, L.-P.;
Wu, B.-S. J. Chem. Soc., Chem. Commun. 1994, 139.
(29) Di Vaira, M.; Stoppioni, P.; Peruzzini, M. Polyhedron 1987, 6, 351.
Scherer, O. J. Acc. Chem. Res. 1999, 32, 751.
(19) Liu, S.-T.; Hu, X.; Chang, F.; Liu, Y.-C.; Ding, E.-R.; Wu, B.-F.;
Zhao, Z.-R. Polyhedron 2002, 21, 1073-1080.
(20) Van Gastel, F.; Taylor, N. J.; Carty, A. J. Inorg. Chem. 1989, 28,
384.
(21) MacLaughlin, S. A.; Taylor, N. J.; Carty, A. J. Inorg. Chem. 1983,
22, 1409.
(22) Lang, H.; Huttner, G.; Zsolnai, L.; Mohr, G.; Sigwarth, B.; Weber,
U.; Orama, O.; Jibril, I. J. Organomet. Chem. 1986, 304, 157-179.
(23) Beruda, H.; Zeller, E.; Schmidbaur, H. Chem. Ber. 1993, 126, 2037-
2040.
(24) Fenske, D.; Persau, C. Z. Anorg. Allg. Chem. 1991, 593, 61.
(25) Sunick, D. L.; White, P. S.; Schauer, C. K. Inorg. Chem. 1993, 32,
5665-5675.
Inorganic Chemistry, Vol. 44, No. 8, 2005 2771

Scoles et al.
Table 4. X-ray Parameters for Compounds 1, 4, 5, 6, 7, and 8
1
4
5
formula
fw
cryst syst
space group
unit cell
a (Å)
b (Å)
c (Å)
â (deg)
V (Å3)
Z
C22H17N O19F3PSRu5
C
48.08H45.52 NO13P3Ru5
C38H23O14 P3Ru5
1301.82
orthorombic
P212121
1224.75
monoclinic
P21/n
1443.64
orthorombic
Pbcn
9.6282(6)
26.152(1)
14.5780(8)
94.373(1)
3660.0(4)
4
2.223
2.207
28.73
43233
20.126(1)
36.805(3)
14.237(1)
90
10546(1)
8
1.819
1.552
25.00
11.8241(6)
17.7276(9)
20.093(1)
90
4211.7(4)
4
2.053
1.931
28.73
45347
F
calc (Mg mm-3
)
µ (Mo KR) (mm-1
max (deg)
reflns measured
)
θ
91420
9286/27/658
0.985
data/restraints/parameters
GOF
9452/1/467
1.047
10878/1/634
1.040
R1 and wR2
[I > 2σ(I)]
0.0248
0.0529
0.0331
0.0556
0.598
0.0426
0.0837
0.0799
0.0983
0.762
0.0209
0,0462
0.0240
0.0462
0.668
R1 and wR2
(all data)
largest peak in final
difference map (e Å-3
)
6
7
8
formula
fw
C40H24 O17F3 P3SCl2Ru5
1534.81
C38H22O13F P3Ru5
1303.82
C39H24O13P3 Cl3Ru5
1405.19
cryst syst
space group
unit cell
a (Å)
b (Å)
c (Å)
â (deg)
V (Å3)
Z
monoclinic
P21/c
monoclinic
P21/n
monoclinic
P21/c
17.8738(9)
12.5377(7)
22.309(1)
94.224(1)
4985.7(5)
4
2.045
1.805
29.60
61079
13.9607(9)
15.263(1)
20.360(1)
108.472(1)
4114.8(5)
4
2.105
1.979
29.61
51170
17.4150(7)
15.0898(6)
17.7268(7)
96.954(1)
4624.1(3)
4
2.018
1.933
28.74
54445
F
calc (Mg mm-3
)
µ (Mo KR) (mm-1
max (deg)
reflns measured
)
θ
data/restraints/parameters
GOF
13922/0/645
1.101
11565/0/541
0.988
11947/0/568
1.029
R1 and wR2
[I > 2σ(I)]
0.0405
0.0912
0.0579
0.0962
1.869
0.0370
0.0718
0.0663
0.0791
0.853
0.0247
0.0618
0.0327
0.0659
0.940
R1 and wR2
(all data)
largest peak in final
difference map (e Å-3
)
3
6.4 Hz, CH], 1.4 [d, J(HH) ) 6.4 Hz, CH3]. FAB-MS (m/z):
973.4 [M+], 974-553 [M-nCO] (n ) 1-15). Anal. Calcd for
C22H17NO19 F3PSRu5: C, 21.58; H, 1.40; N, 1.14. Found: C, 21.79;
H, 1.18; N, 1.14.
c. Synthesis of [Ru5(CO)13(µ-dppm)(µ4-POH)] (5). The cluster
[K][Ru5(CO)15(µ4-PO)] (100 mg, 0.099 mmol) was dissolved in
CH2Cl2 (10 mL) and treated with HCl (100 µL, 1 M solution in
ether), and then dppm (72 mg, 0.187 mmol) was immediately added.
The solvent was removed in vacuo, and the residue was separated
using thin-layer chromatography with CH2Cl2 as the eluent. A dark
green band was isolated, and X-ray quality crystals of [Ru5(CO)13-
(µ-dppm)(µ4-POH)] (5) were grown from CH2Cl2/hexane at -30
°C. Yield: 23 mg, 18%. IR (CH2Cl2, ν CO, cm-1): 2098 w, 2069
m, 2036 m, 2020 s, 2001 m. 31P{1H} NMR (CDCl3): δ 503 [t,
b. Synthesis of [Ru5(CO)13(µ-dppm)(µ-PNiPr2)] (4). The cluster
[Ru5(CO)15(µ4-PNiPr2) (90 mg, 0.085 mmol) and dppm (66 mg,
0.170 mmol) were dissolved in CH2Cl2 (10 mL). The solution was
heated under reflux for 18 h. The solvent was removed in vacuo,
and the residue was separated by thin-layer chromatography on
silica gel plates using a 50:50 mixture of CH2Cl2/hexane as the
eluent. [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4) was isolated as a green
compound. Crystals were grown from CH2Cl2/hexane at -30 °C.
Yield: 42 mg, 35%. IR (CH2Cl2, ν CO, cm-1): 2064 m, 2029 s,
2
1
2J(PP) ) 11 Hz], 25.1 [d, J(PP) ) 11 Hz]. H NMR (CDCl3): δ
2
7.8-7.3 [m, 20H, Ph], 4.68 [dt, 1H, J(HH) ) 14 Hz, PCHHP,
2J(HP) ) 12 Hz], 4.20 [dt, 1H, 2J(HH) ) 14 Hz, PCHHP, 2J(HP)
) 12 Hz]. Anal. Calcd for C38H23O14P3Ru5: C, 35.06; H, 1.78.
Found: C, 35.38; H, 1.80. Acidity measurements on 5 were carried
out by dissolving 15 mg of 5 in CD2Cl2 with varying amounts of
PCy3 (0.5, 1, or 3 equiv). Because the acid species were in rapid
exchange with the conjugate bases, relative concentrations were
measured using the averaged 31P chemical shift. The total phos-
phine-to-cluster ratio was measured using integration. Equilibrium
2011 m. 31P{1H} NMR (CDCl3): δ 500 [t, J(PP) ) 38 Hz], 32
2
[d, 2J(PP) ) 37 Hz]. 1H NMR (CDCl3): δ 7.5-7.0 [m, 20H, Ph],
2
2
5.14 [dt, 1H, J(HH) ) 13 Hz, J(HP) ) 12 Hz, PCHHP], 4.92
[dt, 1H, J(HH) ) 13 Hz, J(HP) ) 12 Hz, PCHHP], 4.37 [sept.,
2H, J(HH) ) 7 Hz, CH], 1.40 [d, 12H, J(HH) ) 7 Hz, CH3].
Anal. Calcd for C44H36NO13P3Ru5: C, 38.16; H, 2.62; N, 1.01.
Found: C, 38.37; H, 2.14; N, 0. 91.
2
2
3
3
2772 Inorganic Chemistry, Vol. 44, No. 8, 2005

Transformation of µ4-Phosphinidines at an Ru5 Center
constants K were calculated using the measured concentrations, and
ether, (0.04 mmol) and H2O (40 µL). The flask was briefly
evacuated, refilled with nitrogen, and then allowed to stir for 2 h
at room temperature. Over that time, the color changed from green
to orange. The solvent was removed in vacuo, and the residue was
separated using thin-layer chromatography with hexane as the
eluent. Orange crystals of [Ru5(CO)13(µ-dppm)(µ-Cl)(µ5-P)] (8)
were grown from 50:50 CH2Cl2/hexane at -30 °C. Yield: 13 mg,
25%. IR (CH2Cl2, ν CO, cm-1): 2070 m, 2043 s, 2023 s, 2009 w,
pKa was then calculated using the relationship pKa ) pKeq - pKBH+
,
using a value of 9.7 for pKBH+ (HPCy3+, aqueous scale).17 The
average pKa value for four experiments was 9.5 ( 0.5.
d. Synthesis of [Ru5(CO)13(µ-dppm)(µ3-H)(µ4-POH)][CF3SO3]
(6). To a solution of [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4) (130 mg,
0.094 mmol) in CH2Cl2 (10 mL) was added water (10 µL, mmol)
and triflic acid (10 µL, mmol). The resulting solution was stirred
for 10 min and then dried over magnesium sulfate and filtered.
The solvent was reduced to 2 mL, and an equal amount of Et2O
was added. The resulting solution was kept at -30 °C for 2 days,
resulting in the formation of dark green crystals. Yield: 30 mg,
22%. IR (KBr pellet, ν CO, cm-1): 2090 m, 2049 w, 2031 s, 2010
2
1989 w, 1967 w. 31P{1H} NMR (CDCl3): δ 803 [t, J(PP) ) 52
2
1
Hz], 28 [d, J(PP) ) 52 Hz]. H NMR (CDCl3): δ 7.8-7.4 [m,
20H, Ph], 3.73 [dt, 1H, 2J(HH) ) 14 Hz, 2J(HP) ) 11 Hz, PCHHP],
3.13 [dt, 1H, 2J(HH) ) 14 Hz, 2J(HP) ) 12 Hz, PCHHP]. FAB-
MS (m/z): 1322 [M+], 1294-1069 [M - nCO]+ (n ) 1-9). Anal.
Calcd for C39H24O13P3Cl3Ru5: C, 33.33; H, 1.72. Found: C, 33.76;
H, 1.39.
2
w. 31P{1H} NMR (CDCl3): δ 497 [t, J(PP) ) 29 Hz], 31.8 [d,
2J(PP) ) 29 Hz]. 1H NMR (CDCl3): δ 7.8-7.1 [m, 20H, Ph], 6.57
[dt, 1H, 2J(HH) ) 13 Hz, 2J(HP) ) 13 Hz, PCHHP], 5.12 [dt, 1H,
X-ray Analysis. Suitable crystals of compounds 1‚[H2NiPr2]-
[CF3SO3], 4, 5, 6, 7, and 8 were mounted on glass fibers. Diffraction
measurements were made on a Siemens SMART CCD automatic
diffractometer using graphite-monochromated Mo KR radiation at
-100 °C. The unit cell was determined from randomly selected
reflections obtained using the SMART CCD automatic search,
center, index, and least-squares routines. Crystal data and collection
parameters are listed in Table 4. Integration was carried out using
the program SAINT, and an absorption correction was performed
using SADABS. Structure solutions were carried out using the
SHELXTL 5.1 suite of programs. Initial solutions were obtained
by direct methods (SHELXS) and subsequently refined by succes-
sive least-squares cycles (SHELXL).
2
2J(HH) ) 13 Hz, J(HP) ) 13 Hz, PCHHP], -18.0 [br, 1H, µ3-
H], 10.4 [br, POH, -80 °C, CD2Cl2]. Anal. Calcd for C39H24O17F3-
SP3Ru5: C, 32.26; H, 1.67. Found: C, 31.98; H, 1.41.
e. Synthesis of [Ru5(CO)13(µ-dppm)(µ4-PF)] (7). To a green
solution of [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4; 119 mg, 0.086
mmol) in CH2Cl2 (10 mL) was added an excess of HBF4 (54% in
Et2O, 20 µL, 24 mg, 0.15 mmol). The resulting green solution was
stirred at room temperature for a half hour. The solvent was
removed in vacuo, and the residue was separated using thin-layer
chromatography with 50:50 CH2Cl2/hexane as the eluent. Crystals
of 7 were grown from 50:50 CH2Cl2/hexane at -30 °C. Yield: 30
mg, 27%. IR (CH2Cl2, ν CO, cm-1): 2074 m, 2042 m, 2025 s,
1
2008 m.31P{1H} NMR (CDCl3): δ 539 [dt, J(PF) ) 1076 Hz,
Acknowledgment. This work was supported by the
National Research Council of Canada and grants from the
Natural Sciences and Engineering Research Council of
Canada (to A.J.C.).
2J(PP) ) 31 Hz], 28.5 [d, 2J(PP) ) 31 Hz]. 19F{1H} NMR (CDCl3
1
3
vs CF3COOH): δ 8.72 [dt, J(PF) ) 1076 Hz, J(PF) ) 20 Hz].
1H NMR (CDCl3): δ 7.5-7.3 [m, 20H, Ph], 4.46 [dt, 1H, 2J(HH)
) 15 Hz, J(HP) ) 11 Hz, PCHHP], 5.12 [dm, 1H, J(HH) ) 15
Hz, PCHHP]. Anal. Calcd for C38H22O13P3FRu5: C, 35.01; H, 1.70.
Found: C, 35.57; H, 1.44.
2
2
Supporting Information Available: Crystallographic data in
CIF format for compounds 1 and 4-8. This material is available
free of charge via the Internet at http://pubs.acs.org.
f. Synthesis of [Ru5(CO)13(µ-dppm)(µ-Cl)(µ5-P)] (8). The
cluster [Ru5(CO)13(µ-dppm)(µ4-PNiPr2)] (4; 55 mg, 0.04 mmol) was
dissolved in CH2Cl2 and treated with HCl (40 µL, 1 M solution in
IC040077E
Inorganic Chemistry, Vol. 44, No. 8, 2005 2773