Behaviour of [RuClCp(mPTA)2](OSO2CF3)2 in water vs. the pH: Synthesis and characterisation of [RuCpX(mPTA)2](OSO2CF3)n, X = (H2O-κO, DMSO-κS, n = 3; OH

Article abstract of DOI:10.1016/j.jorganchem.2009.01.050

The behaviour of [RuClCp(mPTA)₂](OSO₂CF₃)₂ (1) in water solution vs. the pH was studied. Complex 1 is stable in neutral and acidic water solution while in basic water solution another complex, [RuCp(OH-κO)(mPTA)

Full text of DOI:10.1016/j.jorganchem.2009.01.050

Journal of Organometallic Chemistry 694 (2009) 2029–2036
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Behaviour of [RuClCp(mPTA)2](OSO2CF3)2 in water vs. the pH: Synthesis and
characterisation of [RuCpX(mPTA)2](OSO2CF3)n, X = (H2O-
jO, DMSO-jS, n = 3;
OHꢀ-
jO, n = 2) (mPTA = N-methyl-1,3,5-triaza-7-phosphaadamantane)
a
b,
b
Beatriz González a, Pablo Lorenzo-Luis a, , Pedro Gili , Antonio Romerosa , Manuel Serrano-Ruiz
*
*
a Departamento de Química Inorgánica, Facultad de Química, Universidad de La Laguna, La Laguna, Tenerife, Spain
b Área de Química Inorgánica, Facultad de Ciencias, Universidad de Almería, Almería, 04120, Spain
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 8 January 2009
Received in revised form 28 January 2009
Accepted 28 January 2009
Available online 5 February 2009
The behaviour of [RuClCp(mPTA)2](OSO2CF3)2 (1) in water solution vs. the pH was studied. Complex 1 is sta-
ble in neutral and acidic water solution while in basic water solution another complex, [RuCp(OH- O)
O, X = ꢀOSO2CF3,
S, X = ꢀOSO2CF3, n = 3 (5)) were also obtained. All presented
j
(mPTA)2](OSO2CF3)2ꢁ(C4H10O) (2), is obtained. Complexes [RuCp(mPTA)2(L)]ꢁXn (L = H2O-
j
n = 3 (3); L = Cl, X ¼ BFꢀ4 , n = 2 (4); L = DMSO-
j
complexes were characterised by IR and multinuclear (1H, 13C{1H}, 19F{1H}and 31P{1H}) NMR spectroscopy.
Improved synthesis for 1, the thermal analysis of complexes 1–3 and the crystal structure of the complexes
1 and 5 are also presented.
Keywords:
Ruthenium complexes
Aquo-soluble metal complexes
mPTA
Ó 2009 Elsevier B.V. All rights reserved.
Water reactivity
1. Introduction
phosphaadamantane) [7] and its three new derivatives: dmPTA
(N,N0-dimethyl-1,3,5-triaza-7-phosphaadamantane), dmoPTA (3,7-
The aquo-soluble ruthenium(II) complexes containing water-
soluble phosphine ligands have received a great deal of attention
in recent years [1]. Water is employed more and more often as a
medium for the synthesis of organic compounds and study of their
transformations. This approach is advantageous for some impor-
tant reasons: water is abundant, environmentally benign [2] and
reported to be actively involved in a variety of reactions by coordi-
nating to a metal centre and/or by proton transfer [3].
Among aminophosphine ligands, the air-stable, water-soluble,
heterocyclic phosphine 1,3,5-triaza-7-phosphaadamantane (PTA)
has received much attention in recent years as a ligand for the syn-
thesis of water-soluble metal complexes which find use in such
areas as medicine, catalysis, photo-luminescence, etc. [4,5]. Recently
our group has presented the first water-soluble and air-stable het-
erobimetallic polymeric structure containing [CpRuCNRuCp]+ and
[Au(CN)4]ꢀ bridged by PTA through a P,N coordination mode. This
complex displays gel-like properties in water, specifically a ther-
mally controlled volume transition [9]. A number of aqua-soluble
phosphines with the PTA cage modified by cleavage of C–N or C–P
bonds have appeared in literature over the years [6]. We have re-
ported the synthesis of mPTA(OSO2CF3) (N-methyl-1,3,5-triaza-7-
dimethyl-1,3,5-triaza-5-phosphabicyclo[3.3.1]nonane and Hdmo
PTA (3,7-H-3,7-dimethyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]non-
ane) [8]. These ligands are used to obtain new complexes such as
[RuClCp(PPh3)-l-dmoPTA-1j
P:2j2 N,N0-Co(acac-j2O,O0)2] which
catalyses the isomerization of enols to enones [8].
The complex [RuClCp(mPTA)2]ꢁ(OSO2CF3)2 (1) [7] is believed to
be a promising water-soluble catalyst as parent complexes have
shown activity for hydrogenation of olefins in water [10]. The dif-
ficulties of obtaining this complex in substantial amount have lim-
ited study of its properties. In this paper, we present new
procedures, which allow obtaining 1 with a high yield and assess-
ment of its behaviour in water vs. the pH [11].
2. Results and discussion
2.1. Synthesis and behaviour in water of [RuClCp(mPTA)2](OSO2CF3)2
(1)
The complex [RuClCp(mPTA)2](OSO2CF3)2 (1) was previously
synthesised [7] by reaction of RuCl3ꢁxH2O with freshly cracked
cyclopentadiene (Cp) and mPTA(OSO2CF3) in EtOH in low yield
(ꢂ12.9%). We have tried to use two new alternative procedures
for obtaining 1 from the parent complex [RuClCp(PPh3)2] [7],
which are shown in Scheme 1. Reaction of [RuClCp(PPh3)2] with
two equivalents of PTA in refluxing toluene results in the complex
* Corresponding authors.
E-mail addresses: plorenzo@ull.es (P. Lorenzo-Luis), romerosa@ual.es (A. Romer-
osa).
0022-328X/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2009.01.050

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B. González et al. / Journal of Organometallic Chemistry 694 (2009) 2029–2036
Scheme 1. Synthesis of 1.
[RuClCp(PTA)2] [12] that is further selectively methylated on the
NPTA by CH3OSO2CF3 in refluxing chloroform. The complex 1 is ob-
tained by this procedure from [RuClCp(PTA)2] with 74% yield but
from [RuClCp(PPh3)2] the yield is 39.6%. A more convenient syn-
thetic strategy consists in the substitution of two PPh3 groups in
[RuClCp(PPh3)2] by two mPTA(OSO2CF3) in acetone. The composi-
tion of the final product obtained by this reaction depends on the
reactant concentration. In adequate experimental conditions com-
plex 1 is obtained in one step with a yield of 64% while a mixture of
complexes [RuClCp(mPTA)2](OSO2CF3)2 (1) and [RuClCp (mPTA)
(PPh3)](OSO2CF3) (1a) is obtained if concentrations of the reactants
are lower than the optimal ones.
It is important to stress that the reaction of 1a with mPTA
(OSO2CF3)inacetonedidnotgiverisetotheformationof1. Therefore
ifamixtureof bothcompounds(1and1a)is obtained, 1aisnottrans-
formed into 1 by reaction with mPTA(OSO2CF3). Dependence of reac-
tion products on the reactant concentration is not usual in chemical
synthesis of ruthenium phosphine complexes. Theoretical and
experimental studies aimed to elucidate the mechanism of the
reaction between [RuClCp(PPh3)2] and mPTA are in progress and
preliminary results were recently reported by the authors [13].
Slow evaporation of complex 1 in water solution enabled
obtaining crystals of good quality. Monocrystal X-ray diffraction
experiment confirmed the structure earlier proposed for this com-
plex (vide infra) [7]. The stability of complex 1 and its behaviour in
water at various pH were studied previously in order to evaluate
its catalytic properties at pH 5.94, 2.17 and 11.56 as was monitored
by UV–vis absorption spectroscopy. No change in 1 was observed
at acidic pH while a net evolution was observed at basic pH [11].
A D2O solution of 1 was prepared and several fractions of NaOH
solution were added to it. The reaction was monitored by
31P{1H}NMR spectroscopy. The spectra showed that the signal at
ꢀ10.77 was decreasing while the one at ꢀ8.59 ppm (Fig. 1a) was
increasing. The final compound was stable in solution for one
day at room temperature. Addition of NaCl to the solution led to
formation of complex 1 (Fig. 1b).
Fig. 1. (a) (i) 31P{1H} NMR (D2O) of an aqueous solution of [RuClCp(mPTA)2]-
(OSO2CF3)2 (1) (ꢀ10.77 ppm) was reacted with successive addition of (ii) 50 L, (iii)
l
100 lL, (iv) 100 lL, (v) 150 lL and (vi) 300 lL of NaOH in water (0.075 M) at 298 K,
leading to the conversion of 1 (ꢀ10.77 ppm) into 2 (ꢀ8.59 ppm). (b) 31P{1H} NMR
(D2O) of the solution obtained after successive addition of (ii) 25 lL, (iii) 125 lL of
NaCl (0.35 M) into the resulting (a) solution (i) leading to the conversion of 2
(ꢀ8.59 ppm) into 1 (ꢀ10.77 ppm).
Scheme 2. Transformation of 1 into 2 in water solution.
nally isolated by precipitation with Et2O from the reaction of 1 with
AgOSO2CF3 in water. It is important to point out that complex 3
transforms into 2 by reaction with NaOH in water, which supports
the composition proposed for 2 and provides more convenient pro-
cedure for its synthesis (Scheme 3).
It is only possible to justify these results if one initially assumes
that the Clꢀ in [RuClCp(mPTA)2](OSO2CF3)2 (1) is substituted by OHꢀ
The 19F{1H} NMR spectrum of 3 shows a unique singlet at
ꢀ78.72 ppm which is similar to that observed for complex 1
(ꢀ78.84 ppm) and agrees well with the presence of an ionic
ꢀOSO2CF3 molecule [7]. The same signal can be observed also if a
large molar excess of AgOSO2CF3 is introduced in the reaction, indi-
cating that there is no significant interaction between the metal
and the anion ꢀOSO2CF3 (Scheme 3). The IR spectra of both com-
plexes show O–H characteristic bands and their 1H NMR and 13C
NMR (D2O) display typical signals for diethyl ether molecules (vide
infra).
giving rise to the complex [RuCp(OH-
j
O)(mPTA)2](OSO2CF3)2ꢁ
(C4H10O) (2) in which the OHꢀ ligand is easily replaced by Clꢀ bring-
ing back the complex 1 (Scheme 2).
The complex 2 was isolated by precipitation with Et2O from the
reaction of 1 with NaOH in water. All our attempts to obtain good-
quality monocrystals of 2 for X-ray diffraction experiment were
unsuccessful. To support the proposed structure of 2 a lot of effort
has been invested in obtaining the parent water complex [RuCp
(mPTA)2(OH2-
jO)](OSO2CF3)3ꢁ(H2O)(C4H10O)0.5 (3), which was fi-

B. González et al. / Journal of Organometallic Chemistry 694 (2009) 2029–2036
2031
Scheme 3. Reactivity of 1 in water. Synthesis of 2, 3 and 4.
To confirm that assumption the complex [RuClCp(mPTA)2]
(BF4)2 (4) was obtained by reaction of 1 with NaBF4 in water at
room temperature. The resulting orange solid showed similar 1H
and 31P{1H} NMR spectra as those for 1.
and the complex (OC-6-13)-[RuI2(H2O)(mPTA)3]I3 in which one
mPTA is in trans position to the H2O molecule [15]. There are no
data concerning the crystal structure of Cp–mPTA–Ru complex,
that contains the H2O molecule coordinated to the metal [16].
However it is known that in water solution exists a partial equilib-
rium between the complex [CpRuCl(PTA)2] and its water parent
complex [CpRu(OH2)(PTA)2]+ [17].
To have additional information to support the composition of
complexes 2 and 3 a thermogravimetric study in nitrogen atmo-
sphere was performed for both compounds as well as for the com-
plex 1 for comparison purposes. Thermal data of the weight loss for
1–3 complexes are displayed in Table 1.
However inits 19F{1H}NMR spectrum a multipletatꢀ147.90 ppm
was observed which could only be assigned to an ionic BFꢀ4 molecule.
The 31P{1H}NMR spectrum of 3 in D2O showsa singletatꢀ10.69 ppm
which is somewhat different from that of 1 (ꢀ10.77 ppm) but clearly
different from that observed for 2 (ꢀ8.59 ppm). A 31P{1H} spectros-
copy study of the reaction of 1 with AgOSO2CF3 in D2O showed that
the signal for 1 was slowlytransformed into theone observed for 3 as
was precipitating quantitatively AgCl (Fig. 2).
The spectroscopic properties of 3 support the conclusion that
the H2O molecule is coordinated to the metal. Stable ruthenium
complexes containing water are not very common as strong atom
like O-bonds weakly bound soft atoms like the Ru(II). There are
two structurally characterised examples of mPTA–Ru complexes
containing a H2O ligand: the complex [Ru(H2O)2(mPTA)4]6+ [14]
in which all water molecules are in trans position to each other,
Complex 1 has high thermal stability from 25 to ca. 215 °C
while complexes 2 and 3 decompose at 150 °C (Table 1). The TG-
DTG/DTA curves (Fig. 3) for 2 and 3 reveal a first weight loss with
three overlapped stages (see DTG curves), which is likely due to the
loss of H2O and Et2O molecules. In fact, the temperature range
where the first weight loss step occurs agrees well with the data
on other compounds containing solvated and coordinated water
molecules [18] and solvated diethyl ether molecules [19]. The loss
of mass in this process (Table 1) indicates that one H2O molecule
and one Et2O molecule are bound in complex 2 and two H2O mol-
ecules and a half of Et2O molecule are included in complex 3.
Two simultaneous endothermic peaks at 112 and 138 °C are ob-
served for 3 and one endothermic peak at 145 °C for 2, which is in
agreement with the fact that Ru–OH bond is stronger than Ru–OH2
bond. At 215 °C the complex 1 decomposes with a endothermic
peak at 230 °C ([DTG]peak c.a. 232 °C) while complex 2 and 3 show
a continuous weight loss.
To obtain an improved procedure for obtaining complexes 2 and
3 a new synthetic route was planned (Scheme 4).
Complex 1 is soluble and stable in DMSO (70 mg/mL at 288 K)
but the product of the reaction of 1 with AgOSO2CF3 in DMSO crys-
tallises with a good yield. The 1H, 13C{1H}, 31P{1H} NMR spectros-
copy show signals in similar range for mPTA and Cp ligands as
those found in other parents mPTA–Ru complexes [7]. It is impor-
tant to stress that signals for coordinated DMSO are observed at
2.54 and 39.88 ppm in 1H NMR and 13C{1H} NMR, respectively.
The 19F{1H} NMR spectrum reveals a singlet at ꢀ77.74 ppm which
is in agreement with a ionic ꢀOSO2CF3 molecule [7]. The 31P{1H}
NMR (D2O) spectrum shows a single resonance at ꢀ12.73 ppm
which is shifted ꢂ2 ppm downfield from that observed for 1 and
Fig. 2. (i) 31P{1H} NMR (D2O) spectrum for the transformation of [RuClCp(mPTA)2]-
(OSO2CF3)2 (1) (ꢀ10.77 ppm) in [RuCp(mPTA)2(OH2-jO)](OSO2CF3)3ꢁ(H2O)-
(C4H10O)0.5 (3) (ꢀ10.69 ppm) by gently addition of (ii) 2 mg, (iii) 0.6 mg and (iv)
0.8 mg of solid AgOTf.

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B. González et al. / Journal of Organometallic Chemistry 694 (2009) 2029–2036
Table 1
Thermal data of the complexes 1–3 from 25 to 250 °C.
Complexes
D
T (°C)
N0molecules losses
Calcd./found (%)
[DTG]peak
–
49, 125, 142
59, 112, 126
[DTA]peak
°C
°C
(1)
(2)
(3)
25–215
25–150
25–150
–
–
–
145
112, 138
(H2O)1 and (C4H10O)0.95
(H2O)2 and (C4H10O)0.45
10.24/9.79
7.10/6.76
were detected by NMR, which demonstrates its high stability in
water.
Complexes 2 and 3 are well soluble in water, dimethyl sulfox-
ide, less soluble in methanol and insoluble in diethyl ether. It is
important to stress that the water solubility of complex 2 and 3
at 295 K (55 and 30.7 mg/mL, respectively), is larger than that for
1 (16 mg/mL). Both complexes, 2 and 3, are stable enough in water
but exchange easily the OHꢀ and H2O ligand bonded to the metal,
therefore they both are good candidates to mediate catalytic pro-
cesses in water. Further experiments to determine the catalytic
properties of complexes 1, 2 and 3 in water for the isomerization
of enols are in progress [11].
2.2. Structures of [RuClCp(mPTA)2](OSO2CF3)2 (1) and [RuCp(DMSO-
jS)(mPTA)2](OSO2CF3)3 2H2O (5)
Crystals good enough to be used for X-ray structure determina-
tion of 1 and 5 were obtained from an acetone and water solution
by slow evaporation at room temperature. Both compounds crys-
tallized in the monoclinic space group (Table 2) and the perspec-
tive drawing of their crystal structures along with the atom
numbering depicted in Fig. 4. A comparison of the structures of 1
and 5 with related [RuCpꢀ0X(L)(L0)]n+ complexes (Cp0 = 5
g
-C5Hꢀ,
5
Cp; 5g-C8Hꢀ, Dp; 5g-Me5C , Cp*; X = Cl, I, H, L = L0 = PPh3, PTA,
9
5
mPTA) [3,7,8] reveals no major differences.
The Cp rings for the two complexes are essentially planar, the
biggest separation being 0.0009 (C23) for 1 and 0.0345 Å (C5) for
5, from overall plan for the Cp bonded to Ru1. The angle between
the Cpcent plane and the P1–Ru1–P2 plane was found to be
61.15(11)° for 1, which is c.a. 9° greater than that found for 5.
These results are consistent with the values reported for similar
piano-stool complexes (range 51.4–72.7°, mean 59.2°) [3,8]. The
Ru1–Cpcent distance is 1.840 for 1 and 1.883 Å for 5, which are con-
sistent with a Ru–Cpcent bond length found in bibliography (range
1.836–1.929 Å, mean 1.893 Å) [3,7,8]. The P1–Ru1–P2 angle is
Table 2
Crystallographic data of complexes 1 and 5.
Fig. 3. (a) TG/DTG and (b) DTA curves of complexes 1–3. TG = mass loss (%); (b)
DTA =
T (microvolts; (; endo)) and DTG = percent per min.ꢀ1
1
5
D
.
Formula
Fw
Crystal system
Space group
a (Å)
C21H35N6F6ClO6P2S2Ru
844.13
Monoclinic
P2(1)/c
6.5110(2)
20.3062(7)
23.2101(8)
90.00
C24H45N6F9O12P2RuS4
1071.91
Monoclinic
P2(1)/n
15.225(2)
11.407(5)
23.551(3)
90.00
b (Å)
c (Å)
a
(°)
b (°)
90.480(1)
90.00
3068.58(18)
4
90.01(3)
90.00
4090.1(19)
4
c
(°)
V (Å3)
Z
Scheme 4. Synthesis of 5.
dcalcd. (g cmꢀ3
)
1.827
1.687
Absorption coefficient
(mmꢀ1
Data/restrains/parameters
0.924
0.764
)
3 and ꢂ4 ppm from that observed for 2. Its spectroscopic proper-
5408/0/408
R1 = 0.0504;
wR2 = 0.1294
R1 = 0.0570;
wR2 = 0.1439
1.134; ꢀ1.088
9734/0/502
R1 = 0.0763;
wR2 = 0.2061
R1 = 0.1060;
wR2 = 0.2337
2.567; ꢀ0.975
ties support that the composition for the new complex is
Final R indices [I > 2
r(I)]
[RuCp(DMSO-jS)(mPTA)2](OSO2CF3)3 (5), which was finally con-
firmed by single crystal X-ray determination. The exchange of
the DMSO molecule by the H2O molecule was tested by dissolution
of 5 in water at room temperature. Neither after keeping 5 for 24 h
at room temperature or after 72 h at 80 °C, no significant changes
R indices (all data)
Largest diffraction peak, hole
(e Å3)

B. González et al. / Journal of Organometallic Chemistry 694 (2009) 2029–2036
2033
Fig. 4. Complex unit structure of (a) [RuClCp(mPTA)2]2+and (b) [RuCp(DMSO-
kS)(mPTA)2]3+ including the atomic numbering scheme. For clarity, only methyl
hydrogen atoms are included.
Fig. 5. Packing for 1 (a) and 5 (b), including the atomic numbering scheme. Dashed
lines represent the selected intermolecular interactions (the O and F atoms design
are in globe stile).
Similarly, in complex 5 the Owꢁ ꢁ ꢁO distances are coherent with
hydrogen bond: Ow1/Ow2ꢁ ꢁ ꢁO5T/O1T = 3.046(4)–3.033(3) Å [21].
Table 3
Selected bond lengths (Å) and angles (°) for 1 and 5.
1
5
3. Experimental
Ru1–P1
Ru1–P2
Ru1–Cl1
P1–Ru1–P2
P1–Ru1–Cl1
P2–Ru1–Cl1
2.2509(12)
2.2599(12)
2.4213(13)
99.44(4)
84.55(5)
87.04(5)
Ru1–P1
Ru1–P2
Ru1–S1
P1–Ru1–P2
P1–Ru1–S1
P2–Ru1–S1
2.2927(16)
2.2930(16)
2.2632(15)
97.41(6)
90.83(6)
90.78(6)
3.1. Materials
All chemicals were reagent grade and, unless otherwise stated,
used as received by commercial suppliers. Likewise all reactions
were carried out under a pure argon atmosphere in freshly distilled
and oxygen-free solvents using standard Schlenk-tube techniques.
The hydrosoluble phosphines [RuClCp(PPh3)2] and [RuClCp(PTA)2]
were prepared as described in the literature [7,12].
99.94(4)° in 1, which is slightly higher than in 5 (97.41(6)°) and
virtually identical to those found for the analogue in the ruthenium
complexes (range 93.20(2)–100.12(8)° (mean 97.67(6)°) [3,7,8]. As
shown in Table 3, other bond distances and angles fall well in the
range of values reported in literature [3,7,8,20]. Finally, for both
complexes (Fig. 4), the carbon–nitrogen bond distances (N)C–N
corresponding to the nitrogen supporting methyl group (N3/N5
for 1 and N2/N5 for 5) are longer (range 1.503(8)–1.543(8) Å) than
those for the non-substituted nitrogen atoms (range 1.405(9)–
1.481(11) Å). These values are in agreement with those found for
dmoPTA in the cation unit [RuClCp(PPh3)(HdmoPTA]+ [8a].
3.2. General physical methods
1H and 13C{1H} NMR spectra were recorded at room temperature
at 400.13 and 100.62 MHz, respectively, on a Bruker DRX400 instru-
ment. Peak positions are relative to tetramethylsilane and were cal-
ibrated against the residual solvent resonance (1H) or the deuterated
solvent multiplet (13C). 31P{1H} NMR spectra were recorded on the
same instrument operating at 161.97 MHz and the chemical shifts
for 31P{1H} NMR were measured relative to external 85% H3PO4.
19F{1H} NMR spectra were recorded on the same instrument operat-
ing at 376.45 MHz. Infrared spectra were recorded as KBr disks using
a ThermoNicolet Avatar 360 FT-IR spectrometer. Elemental analyses
(C, H, N and S) were performed on a Fisons Instrument EA 1108 ele-
mental analyzer. Thermal analyses were carried out on a Perkin-
Elmer system (mod. Pyris Diamond TG/DTA) under a nitrogen
The crystal packing diagram (Fig. 5) shows an extensive weak
intermolecular interaction among the molecules that provides an
additional stabilization for the structures of the two complexes
[21]. In complex 1, relatively strong Cꢁ ꢁ ꢁO separation is observed
within standard hydrogen bonding distances: C7ꢁ ꢁ ꢁO13T (C7-
ˆ
H7Cꢁ ꢁ ꢁO13T = 2.018(2) Å; H7Cꢁ ꢁ ꢁO13T = 2.840(5) Å; H = 142.5(6)°,
1 ꢀ x, 1 ꢀ y, 1 ꢀ z).

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B. González et al. / Journal of Organometallic Chemistry 694 (2009) 2029–2036
atmosphere (flow rate: 80 cm3 minꢀ1) from 25 to 250 °C. The sam-
ples (ca. 10 mg) were heated in an aluminium crucible (45 mL) at a
rate of 5°C minꢀ1. The TG curves were analysed as mass loss (milli-
grams) as a function of temperature. The number of decomposition
steps was identified in derivative thermogravimetric curves (DTG).
The endo and exo thermal processes were identified by use of differ-
ential thermal analysis curves (DTA).
(1.2 mL) and the mixture was stirred for 4 h at room temperature.
The solution was then filtered several times through Celite to re-
move the AgCl precipitate and was dried under vacuum. The oily
residue was triturated with Et2O (8 ꢃ 5 mL) and the resulting yel-
low-orange powder was dried in vacuum.
Yield: 141.8 mg, 70.1%. C24H44N6F9O11.5P2RuS3 (1030.84 g/mol):
calcd. C 27.98, H 4.26, N 8.15, S 9.31. Found C 28.01, H 4.17,
ꢄC;H2
O
N 8.20; S 9.25%. S22
¼ 55 mg=mL; S22 °C DMSO
,
= 98.33 mg/mL;
ꢄ
3.3. Preparation of [RuClCp(mPTA)2](OSO2CF3)2 (1)
S22
¼ 5:8 mg=mL. IR (KBr, cmꢀ1): m(OTf) 1239, mðH 3459,
C;CH3OH
2OÞ
3357. 1H NMR (D2O): d 1.11 (t, CH3, ether), 2.85 (s, NCH3, 6H), 3.49
(q, CH2, ether), 3.99–4.20 (m, NCH2P, 8H), 4.46–4.61 (m,
NCH2 N + PCH2NCH3, 8H), 4.90 (s, C5H5, 5H). 4.94–5.08 (m,
NCH2NCH3, 8H). 13C{1H} NMR (D2O): d 14.54 (s, CH3, ether), 49.72
The compound was prepared by two alternative processes:
(A) The compound CH3OSO2CF3 (0.081 mL, 0.73 mmol) was
added via a syringe to a solution of [RuClCp(PTA)2] (0.31 g,
0.60 mmol) in 45 mL of chloroform at reflux and kept for
2 h. The resulting yellow precipitate was filtered, washed
with Et2O (2 ꢃ 3 mL) and vacuum-dried.
1
(s, CH3 N), 51.08 (bd, JCP = 37.92 Hz, NCH2P), 52.19 (bd,
1JCP = 32.32 Hz, NCH2P), 60.04 (bd, JCP = 21.08 Hz, CH3NCH2P),
1
66.42 (s, CH2, ether), 69.35 (s, NCH2 N), 77.74 (s, CH3NCH2 N),
80.71 (s, C5H5), 120.10 (q, 1JCF = 315. 19 Hz, OSO2CF3). 31P{1H} NMR
(D2O): d ꢀ10.69 (s). 19F{1H} NMR (D2O): d ꢀ78.72 (s, OSO2CF3).
(B) To a vigorously stirred solution of [RuClCp(PPh3)2] (1 g,
1.38 mmol) in 200 mL of acetone mPTA(OSO2CF3) (0.98 g,
3.05 mmol) was added. Slowly a yellow precipitate was
formed. After 4 h. the resulting powder was collected by fil-
tration, washed with Et2O (2 ꢃ 5 mL) and vacuum-dried.
3.8. Preparation of [RuCp(OH-
j
O)(mPTA)2](OSO2CF3)2ꢁ(C4H10O) (2)
(A) NaOH (6 mg, 0.15 mmol) was added to complex 1 (90.5 mg,
0.11 mmol) dissolved in water (6 mL) and the mixture was
stirred for 1 h at room temperature. The solution was fil-
tered under Ar and dried under vacuum. The oily residue
triturated with with Et2O (8 ꢃ 5 mL) and the resulting pow-
der dried in vacuum.
(B) NaOH (1.72 mg, 0.043 mmol) was added to complex 3
(42 mg, 0.041 mmol) dissolved in water (6 mL) and the mix-
ture was stirred for 1 h at room temperature. The solution
was filtered under Ar and dried under vacuum. The oily res-
idue was triturated with Et2O (8 ꢃ 5 mL) and the resulting
powder dried in vacuum.
ꢄ
Yield: (A) 0.23 g, 74%; (B) 0.65 g, 64%. S25 ; H2O ¼ 16 mg=mL,
S22 °C DMSO
,
= 70 mg/mL. 31P{1H} NMR(DMSO-d6): d ꢀ8.57 (s, mPTA).
Characterisation data agree with those reported [7].
3.4. Reaction of [RuClCp(PPh3)2] with mPTA(OSO2CF3) vs. acetone
volume
Reactions were performed by a similar procedure as described
previously for the synthesis of 1 (method B) but solvent volume
was modified. Two solutions of [RuClCp(PPh3)2] (0.1 g, 0.14 mmol)
and mPTA(OSO2CF3) (0.09 g, 0.28 mmol) in acetone volume
(a) = 10 mL and (b) = 25 mL, were refluxed for 4 h. The precipitates
obtained (i) as an orange powder and (ii) as a yellow-powder, were
filtered under Ar, washed with Et2O (2 ꢃ 2 mL) and vacuum-dried.
Experiment (a, orange-powder): 31P{1H} NMR(DMSO-d6): d ꢀ15.56
(d, 2JPP = 54.81 Hz, mPTA) and 47.25 (d, 2JPP = 54.81 Hz, PPh3) (which
were assigned to [RuClCp(mPTA)(PPh3)](OSO2CF3) (1a) [7]); ꢀ8.57
(s, mPTA) (1) (ratio 1a:1 = 67:33%). Experiment (b, yellow-powder):
31P{1H} NMR(DMSO-d6): d ꢀ8.57 (s, mPTA) (1) (ratio 1a:1 = 0:100%).
Yield: (A) 46.3 mg, 48% (B) 32.30 mg, 76.90%. C25H46N6F6O8P2
RuS2 (899.80 g/mol): calcd. C 33.34, H 5.11, N 7.11, S 9.34. Found C
ꢄC;H2
O
33.12, H 5.14, N 7.20; S 9.12%. S22
¼ 30:7 mg=mL; S22 °C DMSO
,
=
62.7 mg/mL; S22
¼ 19:2 mg=mL . IR (KBr, cmꢀ1):
m(OTf) 1239,
ꢄC;CH3OH
mðH 3533, 3514. 1H NMR (D2O): d 1.11 (t, CH3, ether), 2.84 (s,
2OÞ
NCH3, 6H), 3.49 (q, CH2, ether), 3.98–4.17 (m, NCH2P, 8H), 4.44–
4.63 (m, NCH2 N + PCH2NCH3, 8H), 4.85 (s, C5H5, 5H). 4.93–5.03
(m, NCH2NCH3, 8H). 13C{1H} NMR (D2O): d 14.53 (s, CH3, ether),
1
3.5. Reaction of [RuClCp(mPTA)(PPh3)](OSO2CF3) (1a) with
mPTA(OSO2CF3)
49.64 (s, CH3 N), 51.41 (bd, JCP = 26.72 Hz, NCH2P), 52.64 (bd,
1
1JCP = 35.12 Hz, NCH2P), 60.44 (bd, JCP = 15.44 Hz, CH3NCH2P),
66.54 (s, CH2, ether), 69.31 (s, NCH2 N), 78.24 (s, CH3NCH2 N),
80.58 (s, C5H5), 120.22 (q, 1JCF = 374. 75 Hz, OSO2CF3). 31P{1H} NMR
(D2O): d ꢀ8.59 (s). 19F{1H} NMR (D2O): d ꢀ78.77 (s, OSO2CF3).
Complex 1a (100 mg, 0.13 mmol) was added to mPTA(OSO2CF3)
(49 mg, 0.15 mmol) dissolved in acetone (25 mL) and the mixture
was refluxed for 4 h. The precipitate obtained was filtered, washed
with Et2O (2 ꢃ 2 mL) and vacuum-dried, and the filtered liquor was
evaporated. Bothsolidswereanalysedby31P{1H}NMRwhich showed
that only 1a and mPTA(OSO2CF3) were isolated from the reaction.
3.9. Reaction of 2 with NaCl
The complex 2 (8.0 mg, 0.009 mmol) was dissolved in 0.6 mL of
D2O in a 5 mm NMR tube. The resulting solution was charged with
3.6. Reaction of 1 with NaOH
successive additions of 25, 125 lL of NaCl (0.35 M), leading to con-
version of 2 into 1 to 70 and 100%.
The complex 1 (9.5 mg, 0.011 mmol) was dissolved in 0.7 mL of
D2O in a 5 mm NMR tube. The resulting solution was charged with
3.10. Preparation of [RuClCp(mPTA)2](BF4)2 (4)
successive additions of 50, 100, 100, 150 and 300 lL of NaOH
(0.075 M) at 298 K, leading to conversion of 1 into 2 to ꢂ11%,
NaBF4 (68 mg, 0.62 mmol) was added to complex 1 (100 mg,
0.12 mmol) dissolved in water (5 mL) and the mixture was stirred
for 25 min. at room temperature. The resulting orange precipitate
was filtered, washed with Et2O (2 ꢃ 2 mL) and vacuum-dried.
ꢄ
42%, 66%, 75% and 89%.
3.7. Preparationof[RuCp(mPTA)2(OH2-
(3)
jO)](OSO2CF3)3ꢁ(H2O)(C4H10O)0.5
Yield: 72.8 mg, 73%. S22
¼ 0:29 mg=mL; S22 °C,DMSO
=
C;H2
O
15 mg/mL. C19H35N6P2F8B2RuCl (719.60 g/mol): calcd. C 31.71, H
Complex 1 (200 mg, 0.24 mmol) dissolved in water (20 mL) was
4.86, N 11.67. Found C 31.68, H 4.82, N 11.93%. IR (KBr, cmꢀ1):
added to AgOSO2CF3 (82 mg, 0.32 mmol) dissolved in water
mðBF 1035. NMR spectrum are identical to that found for 1 with
4Þ

B. González et al. / Journal of Organometallic Chemistry 694 (2009) 2029–2036
2035
exception of ꢀOSO2CF3 carbon signal in 13C{1H} NMR. 19F NMR
(DMSO-d6): d 147.90 (m, BF4).
non-disordered atoms for the compounds were refined anisotropi-
cally. The function minimised during the refinement was
2
w ¼ 1=½r2ðF02Þ þ ð0:0700PÞ þ 11:4777Pꢅ for 1 and w ¼ 1=½r2ðF20Þþ
2
3.11. Reaction of 1 with AgTOf
ð0:1186PÞ þ 10:5715Pꢅ for 5. The final geometrical calculations
and the graphical manipulations were carried out with the SHEL-
XS-XTL package [23].
Into a NMR 5 mm tube 1 (9.5 mg, 0.011 mmol), 0.8 mL of D2O
were introduced and 3.4 mg of solid AgOSO2CF3 (0.015 mmol)
was gently added to the water solution. Slowly an AgCl precipitate
was separated, leading to ꢂ58%, 70% and 100% conversion into 3.
4. Conclusions
Investigation of the behaviour of complex 1 in aqueous solution
in the acidic/basic medium showed no significant spectral changes
over time in acidic medium, however in a basic medium complex 1
3.12. Preparation of [RuCp(DMSO-jS) (mPTA)2](OSO2CF3)3 2H2O (5)
AgOSO2CF3 (45.7 mg, 0.18 mmol) dissolved in DMSO (2 mL) was
added to complex 1 (100 mg, 0.12 mmol) dissolved in DMSO
(2 mL) and the mixture was stirred for 17 h at 80 °C and filtered
under vacuum. After addition of Et2O (6x15 mL) a light yellow pre-
cipitate was obtained which was vacuum-dried. Crystals good en-
ough for X-ray determination were obtained by slow evaporation
from a water solution.
transforms to the hydroxyl complex [RuCp(OH-jO)(mPTA)2](O-
SO2CF3)2ꢁ(C4H10O) (2). This process is reversible as addition of ionic
chloride into a water solution of 2 led to 1. Complex [RuCp-
(mPTA)2(OH2-
j
O)](OSO2CF3)3ꢁ(H2O)(C4H10O)0.5 (3) was obtained
from 1 by reaction with Ag(OSO2CF3) in water solution. Complex
2 is also obtained by reaction of 3 with OHꢀ. Substitution reaction
of the Clꢀ bonded to the metal in 1 by DMSO leads to [RuCp(DMSO-
Yield: 96.5 mg, 76.0%. C24H45N6F9O12P2RuS4 (1071.91 g/mol):
calcd. C 26.86, H 4.20, N 7.84, S 11.96. Found C 26.89, H 4.10, N
jS)(mPTA)2](OSO2CF3)3 2H2O (5) which is very stable in solid state
7.67 S 11.52%. IR (KBr, cmꢀ1): m(OTf) 1257, 1061, m(S
@
(DMSO-
and water solution. The high aqua-solubility and the observed easy
exchange of the OH and OH2 ligand at 288 K in 2 and 3 make these
complexes good candidates for being studied as catalytic species in
water.
O)
S)1025. 1H NMR (DMSO-d6): d 2.54 (s, DMSO-S, 6H), 2.78 (s,
NCH3, 6H), 3.91–4.17 (m, NCH2P, 8H), 4.33–4.77 (m,
NCH2 N + PCH2NCH3, 8H), 4.95–5.22 (m, NCH2NCH3, 8H), 5.50 (s,
C5H5, 5H). 13C{1H} NMR (DMSO-d6): d 39.88 (CH3, DMSO-S),
1
48.90 (s, CH3 N), 52.17 (bd, JCP = 34.62 Hz, NCH2P), 53.02 (bd,
Acknowledgments
1
1JCP = 39.42 Hz, NCH2P), 59.88 (bd, JCP = 25.68 Hz, CH3NCH2P),
68.38 (s, NCH2 N), 79.53 (s, CH3NCH2 N), 84.55 (s, C5H5), 121.04
Funding is provided by Junta de Andalucía through PAI (re-
search teams FQM-317) and Excellence Projects FQM-03092, and
the MCYT (Spain) projects CTQ2006-06552/BQU. We also thank
the Consejería de Educación, Cultura y Deportes (Gobierno Autó-
nomo de Canarias, Spain), for supporting B. González.
1
(q, JCF = 320. 15 Hz, OSO2CF3). 31P{1H} NMR (DMSO-d6): d ꢀ11.25
(s). 19F{1H} NMR (DMSO-d6): d ꢀ77.74 (s, OSO2CF3). 1H NMR
(D2O): d 2.85 (s, NCH3, 6H), 3.43 (s, DMSO-S, 6H), 4.01–4.27 (m,
NCH2P, 8H), 4.41–4.62 (m, NCH2 N + PCH2NCH3, 8H), 4.93–5.13
(m, NCH2NCH3, 8H), 5.36 (s, C5H5, 5H).13C{1H} NMR (D2O): d
1
39.88 (m, (CH3)2SO), 49.08 (s, CH3 N), 52.28 (bd, JCP = 37.23 Hz,
References
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NCH2P), 52.68 (bd, JCP = 36.60 Hz, NCH2P), 57.63 (CH3, DMSO-S),
1
60.14 (bd, JCP = 26.14 Hz, CH3NCH2P), 68.61 (s, NCH2 N), 80.03 (s,
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