Routes to ruthenium-fluoro cations of the type [RuL2(CO) nF]+ (n = 2,3; L = PR3, NHC): A play-off between solvent, L and weakly coordinating anion

Article abstract of DOI:10.1002/ejic.201000410

Interaction of cis,cis,trans-[RuF₂(CO)₂(PPh ₃)₂] (1a) with BF₃ in acetonitrile affords the dicationic adduct [Ru(NCMe)₂(CO)₂(PPh₃) ₂](BF₄)(B₂F₇) (2), which can be readily carbonylated to form [Ru(CO)₄(PPh₃) ₂](BF₄)₂ (3). In contrast, reaction of la with BF₃ in dichloromethane leads to the neutral ruthenium-fluoro species [RuF(FBF₃)(CO)₂(PPh₃)₂] (4); facile displacement of the bound FBF3 ligand in 4 occurs on treatment with CO or PPh₃ to afford cationic [RuF(CO)₂(L)(PPh₃) ₂](BF₄) [L = CO (5a), PPh₃ (5b)]. On the other hand, reaction of 1a with PF₅ in dichloromethane furnishes the coordinatively unsaturated 16-electron salt [RuF(CO)₂(PPh ₃)₂](PF₆) (6). Metathesis of the PF₆ anion in 6 with KB(Ar^F)₄ [Ar^F = 3,5-(CF ₃)₂-C₆H₂] in dichloromethane results in rapid decomposition, while in the presence of CO solvent exchange (CH ₂Cl₂) takes place to yield chloride-containing [RuCl(CO)₃(PPh₃)₂]-[B(Ar^F) ₄] (7). Unexpectedly, la proved unreactive towards tris(pentafluorophenyl)borane in dichloromethane. However, by substituting the triphenylphosphane ligands in la with better donor phosphanes or with an N-heterocyclic carbene (NHC) [to give cis,cis,trans-[RuF₂(CO) ₂(L)₂] [L = PEt₂Ph (1b), P(CCPh)Ph₂ (1c), IPr (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) (1d)], fluoride abstraction could be achieved using B(C₆F₂)₃ to give 16-electron [RuF(CO)₂(L)₂][FB(C₆F ₅)₃] (L = PEt₂Ph (8b), P(CCPh)Ph₂ (8c), IPr (8d)]. Carbonylation of 8d proceeds smoothly to generate the coordinatively saturated species [RuF(CO)₃(IPr)₂] [FB(C₂F₅)₃] (9) in high yield. Single crystal X-ray structures are presented for 2, 3, 5a/3, 7 and 9.

Full text of DOI:10.1002/ejic.201000410

FULL PAPER
DOI: 10.1002/ejic.201000410
Routes to Ruthenium–Fluoro Cations of the Type [RuL2(CO)nF]+ (n = 2,3;
L = PR3, NHC): A Play-Off between Solvent, L and Weakly Coordinating
Anion
Karl S. Coleman,[a][‡] John Fawcett,[a] Duncan A. J. Harding,[a] Eric G. Hope,*[a]
Kuldip Singh,[a] and Gregory A. Solan*[a]
Keywords: Ruthenium / Fluorides / Cations / Lewis acids / Phosphane ligands / Carbene ligands / N-Heterocyclic carbenes /
Weakly coordinating anions (WCAs)
Interaction of cis,cis,trans-[RuF2(CO)2(PPh3)2] (1a) with BF3
in acetonitrile affords the dicationic adduct [Ru(NCMe)2-
place to yield chloride-containing [RuCl(CO)3(PPh3)2]-
[B(ArF)4] (7). Unexpectedly, 1a proved unreactive towards tri-
(CO)2(PPh3)2](BF4)(B2F7) (2), which can be readily carbony- s(pentafluorophenyl)borane in dichloromethane. However,
lated to form [Ru(CO)4(PPh3)2](BF4)2 (3). In contrast, reaction
of 1a with BF3 in dichloromethane leads to the neutral ruthe-
nium–fluoro species [RuF(FBF3)(CO)2(PPh3)2] (4); facile dis-
placement of the bound FBF3 ligand in 4 occurs on treatment
with CO or PPh3 to afford cationic [RuF(CO)2(L)(PPh3)2](BF4)
[L = CO (5a), PPh3 (5b)]. On the other hand, reaction of 1a
with PF5 in dichloromethane furnishes the coordinatively un-
saturated 16-electron salt [RuF(CO)2(PPh3)2](PF6) (6). Meta-
thesis of the PF6 anion in 6 with KB(ArF)4 [ArF = 3,5-(CF3)2-
C6H3] in dichloromethane results in rapid decomposition,
while in the presence of CO solvent exchange (CH2Cl2) takes
by substituting the triphenylphosphane ligands in 1a with
better donor phosphanes or with an N-heterocyclic carbene
(NHC) [to give cis,cis,trans-[RuF2(CO)2(L)2] [L = PEt2Ph (1b),
P(CCPh)Ph2 (1c), IPr (1,3-bis(2,6-diisopropylphenyl)imidazol-
2-ylidene) (1d)], fluoride abstraction could be achieved using
B(C6F5)3 to give 16-electron [RuF(CO)2(L)2][FB(C6F5)3] (L =
PEt2Ph (8b), P(CCPh)Ph2 (8c), IPr (8d)]. Carbonylation of 8d
proceeds smoothly to generate the coordinatively saturated
species [RuF(CO)3(IPr)2][FB(C6F5)3] (9) in high yield. Single
crystal X-ray structures are presented for 2, 3, 5a/3, 7 and 9.
veloped reliable routes to a general family of complexes of
the type cis,cis,trans-[RuF2(CO)2(L)2] (1) (Figure 1) that can
bear an assortment of different ancillary ligands (L) includ-
ing organo–phosphanes[11] and N-heterocyclic carbenes
(NHCs).[12]
Introduction
Recent years have seen a surge of interest in the develop-
ment of late-transition metal–fluoro complexes due, in part,
to their potential for mediating selective and efficient car-
bon–fluorine bond forming reactions in organic synthe-
sis.[1–10] With reference to ruthenium(II) chemistry, cationic
ruthenium monofluoro complexes have shown great prom-
ise. For example, Mezzetti et al. reported that the 16-val-
ence-electron salt [Ru(dppp)2F](PF6) (dppp = 1,3-bis(di-
phenylphosphanyl)propane) could fluorinate a range of or-
ganic molecules containing activated carbon–halide
bonds.[10] However, routes to such cationic complexes are
not straightforward and can often necessitate the use of
toxic thallium-based metathesis reagents in combination
with the corresponding ruthenium–chloride precursor. A
more elegant route might involve the selective abstraction
of a fluoride ligand from a neutral ruthenium difluoro spe-
cies with a suitable Lewis acid. In recent years we have de-
Figure 1. cis,cis,trans-[RuF2(CO)2(L)2] (1); L = PR3, NHC.
As part of a preliminary investigation into the chemistry
of 1, we recently reported that a variety of cationic
bis(NHC) complexes are accessible when using boron triflu-
oride as the Lewis acid.[12] However, so far this synthetic
approach has not been conducive to the formation of iso-
lable monofluoro cations of the type [RuF(CO)n(L)2]+ [n =
2 (16 electron), 3 (18 electron)]. We reasoned that the nature
of the Lewis acid, the coordinating capacity of the resulting
fluoro-containing anion, the solvent employed and the an-
cillary ligand L in 1, would each influence the ability to
generate the desired cationic species. To this end we report
in this work a broad study of the chemistry of 1 by: (i) ex-
[a] Department of Chemistry, University of Leicester,
University Road, Leicester LE1 7RH, UK
E-mail: egh1@le.ac.uk
gas8@le.ac.uk
[‡] Current address: Chemistry Department,
University of Durham,
South Road, Durham DH1 3LE, UK
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Routes to Ruthenium–Fluoro Cations
ploring the reactivity of bis(triphenylphosphane)-contain- P(2) 176.31(4)°] with the two pairs of carbonyl and aceto-
ing [RuF2(CO)2(PPh3)2] (1a) towards boron trifluoride as a nitrile ligands configured mutually cis. In 3, the tri-
function of the solvent employed; (ii) probing the reactivity phenylphosphane ligands are again mutually trans [P(1)–
of 1a towards phosphorus pentafluoride; (iii) evaluating tri- Ru(1)–P(1A) 180.00(9)°] but with four carbonyl ligands
s(pentafluorophenyl)borane as the Lewis acid; (iv) varying now occupying the equatorial belt. Between structures a
the coligands at the ruthenium centre in a study of slight elongation of the metal–phosphorus bond lengths is
[RuF2(CO)2(L)2] [L = PEt2Ph (1b), P(CCPh)Ph2 (1c), IPr evident on conversion of 2 to 3 [Ru(1)–P(1) 2.4294(11) Å,
(1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) (1d)].
Ru(1)–P(2) 2.4318(11) Å (2) vs. 2.4528(18) Å (3)]. This
elongation in 3 presumably takes place in order to allow the
four equatorial carbonyl ligands to maximise their back-
bonding capacity. It is worth noting that crystallographi-
cally characterised examples of dicationic mononuclear ru-
thenium carbonyl complexes are rare.[13] There are no inter-
molecular contacts in either structure.
In the 19F NMR spectra of both 2 and 3, a single reso-
nance with a chemical shift characteristic of a BF4 counter-
ion is visible [δ = –155.7 (2), –156.0 ppm (3)]; the presence
of two inequivalent borate counterions for 2, as evidenced
in the solid state, is not apparent in solution. Their 31P
NMR spectra confirm that the two triphenylphosphane
phosphorus atoms in each molecule are located in equiva-
lent positions with a singlet resonance. The υ(CO) bands
[2095, 2050 cm–1 (2); 2084 cm–1 (3)] in the IR spectra are
seen at notably higher wavenumbers than those observed in
precursor 1a (2045, 1973 cm–1),[11b] no doubt reflecting the
dicationic nature of the complexes; an additional strong
υ(CN) band at 2319 cm–1 in 2 confirms the presence of the
bound acetonitrile ligands. Furthermore, the FAB mass
spectra of 2 and 3 support the formulations with fragmenta-
tion peaks corresponding to the loss of acetonitrile (2) or
carbonyl (3) from the corresponding dications.
Results and Discussion
1. Reactivity of 1a towards BF3
Interaction of 1a with BF3·OEt in acetonitrile at room
temperature gave on workup [Ru(NCMe)2(CO)2(PPh3)2]-
(BF4)(B2F7) (2) as an air- and moisture-sensitive white solid
in good yield (Scheme 1). Substitution of the labile acetoni-
trile ligands in 2 to give [Ru(CO)4(PPh3)2](BF4)2 (3) could
also be readily achieved on carbonylation. Both 2 and 3
have been characterised by a combination of multinuclear
NMR (1H, 19F, 31P) and IR spectroscopy along with FAB
mass spectrometry (see Table 1 and Exp. Section). In ad-
dition, both complexes have been the subject of single-crys-
tal X-ray diffraction studies.
Crystals of 2 and 3 suitable for X-ray determinations
were both grown by vapour diffusion of hexane into satu-
rated dichloromethane solutions of the respective complex.
Each structure consists of a distorted octahedral dicationic
unit charge-balanced by either two tetrafluoroborate anions
(3) or one tetrafluoroborate anion and one heptafluorodi-
borate anion (2). In 3 the ruthenium atom is located on a
centre of symmetry. Perspective views of the dicationic units
With the intent of preventing the abstraction of both
in 2 and 3 are shown in Figures 2 and 3, respectively; se- fluoride ligands in 1a, the reaction was then attempted in
lected bond lengths and angles are collected in Tables 2 and the presence of a noncoordinating solvent. Hence, reaction
3, respectively. Within the cation in 2, the two tri- of 1a with BF3 at –78 °C in dichloromethane afforded
phenylphosphane ligands are disposed trans [P(1)–Ru(1)– [RuF(FBF3)(CO)2(PPh3)2] (4) in near-quantitative yield
Scheme 1. Reagents and conditions: (i) BF3·OEt2 (xs), MeCN, r.t.; (ii) CO, CH2Cl2, r.t.; (iii) BF3, CH2Cl2, –78 °C; (iv) CO or PPh3,
CH2Cl2, r.t.; (v) PF5, CH2Cl2, r.t.; (vi) KB(ArF)4, CH2Cl2, r.t.; (vii) CO, CH2Cl2, r.t.
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Table 1. Spectroscopic data for the new complexes 2–9.
v(CO) [cm–1 [a]
]
1H NMR [δ][b]
19F NMR [δ][c]
31P NMR [δ][d]
27.2 (s, RuP2)
FAB-MS
2
2095 (s), 2050 (s), 7.50–7.30 (m, 30 H, Ar–H), 1.67
–155.7 (s, BF4)
362 [MH – B3F11 – MeCN]2+
v(CN) 2319 (br)
(s, 6 H, CH3)
3
4
2084 (s)
7.65–7.40 (m, 30 H, Ar–H)
–156.0 (s, BF4)
21.6 (s, RuP2)
23.4 (br. s, RuP2)
328 [MH – 2BF4 – 3CO]2+
[e]
2072 (s), 2002 (s) 7.5–7.30 (m, 30 H, Ar–H)
–149.5 [d, 3F, 2J(FF) = 78,
Fa], –237.6 (m, 1F, Fb), –330.0
[dm, 1F, 2J(FbFc) = 87, Fc]
5a 2163 (m), 2103
7.50–7.60 (m, 30 H, Ar–H)
–156.0 (s, 4F, BF4), –438.0 [t, 22.8 (d, 2J(PF) = 20, RuP2) 701 [M – BF4 – CO]+, 673 [M –
(s), 2077 (s)
1F, 1J(PF) = 20, RuF]
BF4 – 2CO]+, 653 [M – BF4 –
2CO – F]+
5b 2054 (s), 1985 (s) 7.50–7.30 (m, 45 H, Ar–H)
–155.9 (s, 4F, BF4), –393.7
9.4 [dt, 2J(PF) = 22, 2J(PP) 963 [M – BF4]+, 701 [M – BF4
–
[app. q, 1F, 2J(PF) = 22, RuF] = 29, RuPcis], 14.3 [dd,
PPh3]+
2J(PP) = 29, 2J(PF) = 22,
RuPtrans
]
6
7
2073 (s), 2006 (s) 7.70–7.30 (m, 30 H, Ar–H)
–72.7 [d, 6F, 1J(PF) = 713,
PF6], –345.1 [t, 1F, 1J(PF) =
19, RuF]
16.6 [d, 2J(PF) = 20, RuP2], 653 [M – F – CO – PF6]+, 625
–144.2 [sept, 1J(PF) = 711,
PF6]
17.3 (s, RuP2)
[M – F – 2CO – PF6]+
2073 (s), 2011 (s) 7.60–7.35 (m, 30 H, Ar–H)
–62.4 (s, 6F, Ar–CF3)
689 [M – B(ArF)4 – 2CO]+, 654
[MH – B(ArF)4 – 2CO – Cl]+, 625
[MH – B(ArF)4 – 3CO – Cl]+
576 [M – BF(C6F5)3 – CO]+, 557
[M – BF(C6F5)3 – CO – F]+
720 [M – BF(C6F5)3 – CO]+, 692
[M – BF(C6F5)3 – 2CO]+, 673
[M – BF(C6F5)3 – 2CO – F]+
[f]
[f]
[f]
8b 2066 (s), 2005 (s)
8c 2070 (s), 2005 (s), 7.99 (m, 2 H, Ar–H), 7.76 (m, 4
–135.0 (m, 6F, ArF), –160.0
[t, 3F, 3J(FF) = 22, p-Ar–F],
–165.2 (m, 6F, Ar–F), –182.4
(s, 1F, BF), –351.9 [t, 1F,
3J(PF) = 20, RuF]
–1.9 [t, 3J(PF) = 20, RuP2]
v(CϵC) 2177 (s)
H, Ar–H), 7.37 (m, 24 H, Ar–H)
8d 2063 (s), 2011 (s) 7.42 [t, 4 H, 3J(HH) = 7.7, p-Ar–
–135.1 (m, 6F, Ar–F), –162.0
953 [M – BF(C6F5)3]+
[g]
H], 7.17 [d, 8 H, 3J(HH) = 7.8, m- [t, 3F, 3J(FF) = 20, p-Ar–F],
Ar–H], 6.97 (s, 4 H, NCHCHN),
–166.4 (m, 6F, Ar–F), –190.9
(s,br, 1F, BF), –291.3 (s, 1F,
RuF)
2.41 [ps t, 4 H, 3J(HH) = 6.6,
CH3CH], 2.24 [ps t, 4 H, 3J(HH)
= 6.2, CH3CH], 1.27 [d, 12 H,
3J(HH) = 6.3, CH3CH], 1.06 (m,
12 H, CH3CH)
[g]
953 [M – BF(C6F5)3 – CO]+
9
2062 (s), 2011 (s) 7.41 [t, 4 H, 3J(HH) = 7.9, p-Ar–
–135.1 (m, 6F, Ar–F), –161.9
H), 7.15 [d, 8 H, 3J(HH) = 7.6, m- [t, 3F, 3J(FF) = 20, Ar–F],
Ar–H], 7.10 (s, 4 H, NCHCHN),
–166.3 (m, 6F, Ar–F), –189.9
(s,br, 1F, BF), –432.6 (s, 1F,
2.22 [sept, 4 H, 3J(HH) = 6.7,
CH3CH], 0.96 [d, 12 H, 3J(HH) = RuF)
6.8, CH3CH], 0.93 [d, 12 H,
3J(HH) = 6.8, CH3CH]
[a] Recorded with a Perkin–Elmer Spectrum One ATR-FTIR spectrometer. [b] Recorded in CDCl3 at 293 K, chemical shifts in ppm
relative to SiMe4, coupling constants in Hz. [c] Recorded in CDCl3 at 293 K (2, 3, 6–9) or in [D6]acetone at 184 K (4) and 293 K (5a,
5b), chemical shifts in ppm relative to CFCl3, coupling constants in Hz. [d] Recorded in CDCl3 at 293 K or [D6]acetone at 203 K (3) and
293 K (5a, 5b), chemical shifts in ppm relative to 85% H3PO4, coupling constants in Hz. [e] Not recorded. [f] Because of solubility
problems acceptable NMR spectra could not be obtained. [g] No phosphorus atoms present.
Figure 2. Molecular structure of the dicationic unit in 2 including
a partial atom numbering scheme; all hydrogen atoms have been
omitted for clarity.
Figure 3. Molecular structure of the dicationic unit in 3 including
a partial atom numbering scheme; all hydrogen atoms have been
omitted for clarity.
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Routes to Ruthenium–Fluoro Cations
Table 2. Selected bond lengths [Å] and angles [°] for 2.
[RuF(CO)2(L)(PPh3)2](BF4) [L = CO (5a), PPh3 (5b)] in
near quantitative yields (Scheme 1). Complex 5a has pre-
viously been synthesised by an alternative route and indeed
its spectroscopic properties closely match the data reported
in this work.[11b] The 19F NMR spectrum of 5b shows two
signals, one corresponding to the discrete BF4 counterion
(δ = –155.9 ppm) and the other to the bound fluoride
(δ = –393.7 ppm), the latter taking the form of an apparent
quartet. This multiplicity is presumably an overlapping
doublet of triplets with the metal-bound fluoride ligand
coupling to the cis triphenylphosphane and the equivalent
trans triphenylphosphanes. The signal for the coordinated
fluoride is substantially upfield shifted when compared to
precursor 4 but falls in the range found for previously
Bond lengths
Ru(1)–C(1)
Ru(1)–C(2)
Ru(1)–N(1)
Ru(1)–N(2)
1.889(4)
1.887(4)
2.096(3)
2.073(3)
Ru(1)–P(1)
Ru(1)–P(2)
C(5)–N(2)
C(3)–N(1)
2.4294(11)
2.4318(11)
1.126(5)
1.128(5)
Range of B–F (in BF4 and B2F7 anions): 1.363(6)–1.513(8)
Bond angles
P(1)–Ru(1)–P(2) 176.31(4)
C(1)–Ru(1)–C(2) 92.33(16)
C(1)–Ru(1)–N(1) 95.19(15)
C(1)–Ru(1)–N(2) 176.55(15)
C(1)–Ru(1)–P(1) 90.47(12)
C(1)–Ru(1)–P(2) 90.51(12)
Table 3. Selected bond lengths [Å] and angles [°] for 3.
reported
monofluoro
ruthenium
cationic
com-
Bond lengths
pounds.[10a,11c,14] The 31P{1H} NMR spectrum of 5b reveals
two mutually coupled resonances at δ = 9.4 and δ =
14.3 ppm in a 1:2 ratio along with additional doublet multi-
plicities for each signal from the 2J(PF)cis couplings (ca.
22 Hz).
Ru(1)–C(1)
Ru(1)–C(2)
Range of B–F (anions): 1.2738–1.4920
1.960(8) Ru(1)–P(1)
1.938(9)
2.4528(18)
Bond angles
C(1)–Ru(1)–C(2)
89.9(4) C(1)–Ru(1)–P(1)
94.1(2)
Unexpectedly during an attempt to grow crystals of 4
suitable for a single X-ray diffraction study, the structure of
5a was determined as part of a 50:50 superimposed mixture
with complex 3. Furthermore, the fluoride ligand within the
cationic component in 5a was disordered across four equa-
C(1)–Ru(1)–C(2A) 90.1(4) C(1)–Ru(1)–P(1A) 85.9(2)
C(1)–Ru(1)–C(1A) 180.0(5) P(1)–Ru(1)–P(1A) 180.00(9)
The atoms labelled with A are generated by symmetry (1 – x, –y, –z)
(Scheme 1). The 19F NMR spectrum of 4 (recorded in [D6]- torial sites resulting in an overall 12.5% fluoride site occu-
acetone at –89 °C), confirmed the presence of a bound pancy. An attempt to solve the structure in the P1 and Cc
FBF3 unit with two signals attributable to Fa and Fb in a space groups rather than the C2/c space group (the pre-
3:1 ratio (see Scheme 1 for labelling). The signal for Fa takes ferred one), gave the same disorder problems. As a conse-
the form of doublet because of the two-bond coupling to quence the affected carbonyl and fluoride atoms were re-
Fb, and its chemical shift (δ = –149.5 ppm) is typical of a fined isotropically and thus reliable discussion of the associ-
fluorine atom bound to a trivalent boron atom. The signal ated metric data is limited. Nevertheless, the Ru–F dis-
for Fb is poorly resolved because of the coupling to Fa, the tances of ca. 2.117 Å fall in the range found for related ru-
trans phosphane ligands and the ruthenium-bound Fc, thenium(II) complexes.[10a,11,12] It should be mentioned that
while its chemical shift (δ = –237.6 ppm) is comparable with such CO/F scrambling has been noted elsewhere.[12] A view
that found in related complexes containing a Ru–Fb–B link- of the superimposed cations is shown in Figure 4; selected
age.[14] Equally, the signal for Ru–Fc is poorly resolved, but
a doublet with a coupling constant of 87 Hz is detectable,
which can be assigned to a 2J(FcFb)cis coupling; its chemical
shift (δ = –330.0 ppm) is in the region associated with fluo-
ride terminally bound to ruthenium.[11] Similarly, the low
temperature 31P{1H} NMR spectrum of 4 was poorly re-
solved with a broad resonance at δ = 23.4 ppm attributable
to the equivalent trans-configured triphenylphosphanes. It
is uncertain why the spectra are broad even at low tempera-
ture but it is likely that this is a result of the lability of the
FBF3 ligand in solution (vide infra). The IR spectrum of 4
shows two υ(CO) bands typical of a cis arrangement of car-
bonyl ligands while six bands for the υ(10BF) and υ(11BF)
stretches are visible for the coordinated FBF3 group.[15] The
capacity of [BF4]– to coordinate to an electron-deficient
centre is well established spectroscopically and a number
of ruthenium complexes containing such ligands have been
crystallographically characterised.[12,16]
In order to probe the anticipated lability of the bound
FBF3 group in 4, its reactivity towards donor ligands was
examined. Hence, treatment of 4 with CO or triphenylphos-
3 including a partial atom numbering scheme; all hydrogen atoms
phane in dichloromethane at room temperature gave have been omitted for clarity.
Figure 4. Molecular structure of the disordered cationic unit in 5a/
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E. G. Hope, G. A. Solan et al.
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bond lengths are listed in Table 4. It would seem probable romethane solution containing the complex. A perspective
that 5a/3 represents a decomposition product formed dur- view of the cation in 7 is shown in Figure 5; selected bond
ing the crystallisation of 4.
lengths are collected in Table 5. The structure reveals the
presence of the cationic unit charge-balanced by a discrete
[B(ArF)4]– counterion. Within the cation the two tri-
phenylphosphane ligands are disposed mutually trans, with
the equatorial sites being filled by three carbonyl ligands
and a chloride so as to complete an essentially octahedral
geometry. The metal–phosphorus bond lengths [Ru(1)–P(1)
2.419(3) Å, Ru(1)–P(2) 2.437(4) Å] are comparable with
those found in 2 and similar to those found in the structur-
ally related salt [RuCl(CO)2(NH=NPh)(PPh3)2](ClO4).[19]
There are no inter-ion contacts of note.
Table 4. Selected bond lengths [Å] and angles [°] for 5a/3.[a]
Bond lengths
Ru(1)–P(1)
Range of B–F (anion): 1.315(12)–1.372(11)
2.4410(18)
Bond angles
P(1A)–Ru(1)–P(1)
180.00(8)
[a] The atoms labelled with A are generated by symmetry (1 – x +
1/2, –y + 1/2).
2. Reactivity of 1a towards PF5
On the basis of spectroscopic and crystallographic stud-
ies it has previously been proposed that the coordinating
ability of fluoro-containing anions decreases in the order
[BF4]– Ͼ [PF6]–.[17] With a view to exploiting this trend to
prepare coordinatively unsaturated cationic monofluoro
complexes, 1a was treated with PF5 in dichloromethane at
ambient temperature; complex [RuF(CO)2(PPh3)2](PF6) (6)
was isolated in high yield as a white solid (Scheme 1). Char-
acterisation by multinuclear NMR spectroscopy supports
the formulation of 6 as a 16-electron ruthenium–fluoro cat-
ion charge-balanced by a discrete hexafluorophosphate
anion. In the 19F NMR spectrum the PF6 anion is seen
1
as a characteristic doublet at δ = –72.7 ppm with a J(PF)
coupling constant (ca. 71.3 Hz) that is mirrored in the sep-
tet signal found in the 31P NMR spectrum. Unlike 4, the
Figure 5. Molecular structure of the cationic unit in 7 including a
bound fluoride takes the form of a triplet [1J(PF) = 19 Hz] partial atom numbering scheme; all hydrogen atoms have been
in the 19F NMR spectrum, while the 31P NMR spectrum
omitted for clarity.
displays a doublet for the equivalent phosphane ligands
Table 5. Selected bond lengths [Å] and angles [°] for 7.
coupling to the cis fluoride. Attempts at recording the
NMR spectrum at a lower temperature (–80 °C, in CD2Cl2)
gave no evidence of any interaction with the ruthenium cen-
tre.
Bond lengths
Ru(1)–Cl(1)
Ru(1)–C(1)
Ru(1)–C(2)
2.411(3)
1.965(12)
1.911(11)
Ru(1)–C(3)
Ru(1)–P(1)
Ru(1)–P(2)
1.981(14)
2.419(3)
2.437(4)
With the aim to indisputably confirm that the [PF6]–
anion in 6 undergoes only minimal anion–metal interac-
tions in solution (cf. 4), an anion exchange reaction with
the well-documented “superweak” coordinating anion
[B(ArF)4]– [ArF = 3,5-(CF3)2C6H3][18] was undertaken.
Hence, 6 was treated with the potassium salt of the borate
in dichloromethane at room temperature (Scheme 1). The
31P and 19F NMR spectra of the product indicated that
Range of B–C (anion): 1.607(16)–1.657(14)
Bond angles
Cl(1)–Ru(1)–C(1)
Cl(1)–Ru(1)–C(2)
Cl(1)–Ru(1)–C(3)
93.5(3)
177.3(4)
90.6(4)
Cl(1)–Ru(1)–P(1) 88.64(11)
Cl(1)–Ru(1)–P(2) 88.38(11)
P(1)–Ru(1)–P(2)
176.80(13)
Inspection of the upfield region of the 19F NMR spec-
anion metathesis had been successful, however, it was ap- trum of 7 confirmed the absence of a signal corresponding
parent that rapid decomposition of the product occurred in to a bound fluoride while a signal characteristic of the CF3
solution. To circumvent this instability carbon monoxide resonances for the borate were clearly visible more down-
was introduced and [RuCl(CO)3(PPh3)2][B(ArF)4] (7) was field (δ = –62.4 ppm). In the 31P{1H} NMR spectrum the
isolated in good yield. Complex 7 was characterised by mul- presence of a singlet is in agreement with the trans configu-
tinuclear NMR spectroscopy, IR spectroscopy, mass spec- ration of the phosphane ligands and the absence of a neigh-
trometry and by microanalysis (see Table 1 and Exp. Sec- bouring fluorine ligand. The positive FAB mass spectrum
tion). A single-crystal X-ray diffraction study was also per- reveals fragmentation peaks arising from the loss of both
formed.
carbonyl and chloride ligands from the cationic unit, while
Crystals of 7 suitable for the X-ray determination were the negative FAB mass spectrum shows a peak correspond-
grown by slow diffusion of hexane into a saturated dichlo- ing to the [B(ArF)4]– anion.
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Routes to Ruthenium–Fluoro Cations
It would seem likely that 7 is formed by halide exchange
with the dichloromethane present as solvent. Indeed, fluo-
ride exchange between a fluoro-containing transition-metal
complex and a chlorinated solvent is not uncommon.[20]
Significantly, however, the exchange of the [PF6]– for a non-
coordinating [B(ArF)4]– anion appears to have facilitated
this exchange reaction. It is therefore tempting to suggest
that the [PF6]– anion in 6 does in fact (though not revealed
in the NMR spectra) exert some mild stabilisation to the
16-electron [RuF(CO)2(PPh3)2]+ cation that inhibits the ex-
change process. Conversely with [B(ArF)4]– as the anion,
the “naked” 16-electron cation is now susceptible to halide
exchange.
3. Reactivity of 1a–1d towards B(C6F5)3
In recent years tris(pentafluorophenyl)borane has often
been employed as a Lewis acid for the abstraction of a vari-
ety of anionic ligands and generally the resultant anions
have been regarded as noncoordinating or weakly coordi-
nating.[18,21] To explore its use as a Lewis acid for fluoride
abstraction, 1a was treated with B(C6F5)3 in dichlorometh-
ane at ambient temperature (Scheme 2). Unexpectedly, an
analysis of the reaction mixture by NMR spectroscopy re-
vealed only the presence of unreacted starting material.
Given that reaction of 1a with BF3 readily occurs, it was
postulated that B(C6F5)3 was not a strong enough Lewis
acid to abstract a fluoride ion from 1a. It was, therefore,
reasoned that an increase in the lability of the Ru–F bond
in 1 might facilitate the transformation. Hence the reactiv-
ity of B(C6F5)3 towards cis,cis,trans-[RuF2(CO)2(L)2] [L =
PEt2Ph (1b), P(CCPh)Ph2 (1c), IPr (1d)] was investigated in
which the two PPh3 groups in 1a were replaced by more
electron-donating ancillary ligands. Thus, treatment of 1b–
1d with B(C6F5)3 in dichloromethane at room temperature
gave the 16-electron [RuF(CO)2(L)2][FB(C6F5)3] (L =
PEt2Ph (8b), P(CCPh)Ph2 (8c), IPr (8d)] compounds as
pale-yellow solids in high yield (Scheme 2). In the case of
8b the poor solubility of the product precluded characteri-
sation by NMR spectroscopy. Otherwise all the complexes
have been characterised by a combination of IR spec-
Scheme 2. Reagents and conditions: (i) B(C6F5)3, CH2Cl2, r.t.;
(ii) CO, CH2Cl2, r.t.
the cationic nature of the complexes. In 8c the presence of
a nonbonded alkyne unit was confirmed by the presence of
the υ(CϵC) band at 2177 cm–1 in its IR spectrum.
Carbonylation of 8d under ambient conditions proved
facile affording [RuF(CO)3(L)2][FB(C6F5)3] (9) as a white
solid in quantitative yield. Confirmation of its formulation
was made on the basis of IR spectroscopy, multinuclear
NMR spectroscopy, mass spectrometry and elemental
analysis. A crystal of 9 was also subject to a single-crystal
X-ray diffraction study. Unfortunately, the data was not
stable to full anisotropic refinement due to poor crystal
quality. Nevertheless, the gross structure revealed the pres-
ence of a coordinatively saturated fluoro cation along with
a noncoordinating [FB(C6F5)3]– anion; a view of the cat-
ionic unit in 9 is depicted in Figure 6. Notably, crystallo-
graphically characterised examples of complexes containing
1
troscopy, H, 19F and 31P NMR spectroscopy, FAB mass
spectrometry and elemental analysis (see Table 1 and Exp.
Section).
In the FAB mass spectra of 8b–8d, peaks consistent with
the cationic unit or fragmentation peaks corresponding to
the loss of carbonyl ligands are evident. In the 19F NMR
spectra of 8c and 8d, a signal for the B–F fluoride within
the anion was clearly visible [δ = –182.4 ppm (8c),
–190.9 ppm (8d)], while the Ru–F resonance could be seen
upfield [δ = –351.9 ppm (8c), –291.3 ppm (8d)] as a triplet
for 8c (2J(PF) = 20 Hz) or as a singlet for 8d. In the 31P
NMR spectrum of 8c, a mutually coupled doublet was ob-
served corroborating the presence of a single metal-bound
fluoride. In 8d the equivalency of the resonances resulting
from the two IPr groups observed in the 1H NMR spectrum
supports their trans configuration. For all three salts, the
υ(CO) bands were found at higher wavenumbers than those
Figure 6. Molecular structure of the cationic unit in 9 including a
partial atom numbering scheme; all hydrogen atoms have been
for their corresponding difluoro precursor,[11,12] reflecting omitted for clarity.
Eur. J. Inorg. Chem. 2010, 4130–4138
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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4135

E. G. Hope, G. A. Solan et al.
FULL PAPER
a [FB(C6F5)3]– anion are rare.[22] As expected the 19F reso-
nances for the borate anion remained unaffected on carbon-
ylation but the resonance arising from the ruthenium-
bound fluoride ion underwent a considerable upfield shift
when compared to that in 8d [δ = –432.6 ppm (9) vs.
–291.3 ppm (8d)]. A similar shift in the Ru–F resonance has
previously been observed for the carbonylation of
[RuF(dppp)2][PF6].[10a]
duced pressure to afford a white solid. Following crystallisation
from firstly dichloromethane/diethyl ether (1:100) and secondly
from dichloromethane/hexane (1:100), 2 could be obtained as an
air- and moisture-sensitive white powder (0.332 g, 95%). Single
crystals suitable for an X-ray diffraction study were grown by slow
diffusion of hexane into a saturated dichloromethane solution of
2. C42H36B3F11N2O2P2Ru (1004.90): calcd. C 50.15, H 3.58, N
2.79; found C 50.26, H 3.61, N 2.74. FAB mass spectrum, m/z =
(–FAB) 87 (BF ). IR (solid state): ν = 2319 (br, CN), 2095 (s, CO),
˜
4
Interestingly the formally 16-electron complexes 8c and
2050 (s, CO), 1483 (s), 1432 (s), 1066 (BF4), 836 (s), 744 (s), 685
8d appear stable in solution. By analogy with 6, it would (s) cm–1. See Table 1 for additional spectroscopic data.
seem plausible that the [FB(C6F5)3]– ion also provides some
Synthesis of 3: A Schlenk vessel was charged with 2 (0.300 g,
subtle stabilisation to the electron-deficient ruthenium cen-
tre (although not detectable by NMR spectroscopy). As
with 4, any contact the anion in 8 exhibits with the metal
centre can readily be removed on introduction of CO.
0.299 mmol) and dichloromethane (10 mL) was introduced. Car-
bon monoxide was bubbled through the solution at ambient tem-
perature for 30 min. The resulting colourless solution was transfer-
red to a second vessel containing diethyl ether (200 mL) and the
precipitate was collected by filtration. Recrystallisation of the solid
from dichloromethane/hexane (1:150) gave 3 as an air- and moist-
ure-sensitive white solid (0.259 g, 95%). Single crystals suitable for
an X-ray diffraction study were grown by slow diffusion of hexane
into a saturated dichloromethane solution of 3. FAB mass spec-
Conclusions
By systematic variation of the Lewis acid, solvent and
electronic properties of 1, ruthenium–fluoro cations of the
type [RuL2(CO)nF]+ (n = 2,3) have been successfully iso-
lated. In the case of the formally 16-electron cations (n = 2),
it would appear that the coordinating nature of the anion is
vital for providing some mild stabilisation (see 4, 6 and 8);
with a “superweak” anion like [B(ArF)4]– decomposition
occurs.
trum, m/z = (–FAB) 87 (BF ). IR (solid state): ν = 3059 (br), 2084
˜
4
(s, CO), 1479 (s), 1432 (s), 1049 (vs., BF4), 747 (s), 691 (s) cm–1.
See Table 1 for additional spectroscopic data.
Synthesis of 4: Complex 1a (0.03 g, 0.04 mmol) was loaded, in the
dry-box, into a prefluorinated FEP (perfluoroethylene/propylene
copolymer) tube [4 mm outside diameter (o.d.)]. The FEP tube was
connected to a metal vacuum line and the connectors were passiv-
ated. Dichloromethane (0.3 mL) was condensed into the tube at
–196 °C under a static vacuum. The contents were warmed to
–78 °C and then placed under boron trifluoride gas (1 atm) giving
a yellow solution. The solvent was then removed under reduced
pressure to give 4 as an off-white solid (0.030 g, 90%). See Table 1
for spectroscopic data.
Experimental Section
General Remarks: All reactions, unless otherwise stated, were car-
ried out under an atmosphere of dry, oxygen-free nitrogen, using
standard Schlenk-line or metal vacuum-line techniques or in a ni-
trogen purged dry box. Solvents were distilled under nitrogen from
appropriate drying agents and degassed prior to use.[23] The infra-
red spectra were recorded with a Perkin–Elmer Spectrum One
FTIR spectrometer on solid samples. The ES (electrospray) and the
FAB mass spectra were recorded using a micromass Quattra LC
mass spectrometer and a Kratos Concept spectrometer with meth-
anol or 3-nitrobenzyl alcohol as the matrix, respectively. 1H, 31P,
19F and 13C NMR spectra were recorded with a Bruker spectrome-
ter (ARX 250, AM 300 or DRX 400 MHz) at ambient tempera-
ture; chemical shifts (δ) for the 1H and 13C NMR spectra were
referenced internally to TMS (δ = 0 ppm) while the 19F and 31P
NMR were referenced externally to CFCl3 (δ = 0 ppm) and 85%
H3PO4 (δ = 0 ppm), respectively. Elemental analyses were per-
formed at the Science Technical Support Unit, London Metropoli-
tan University.
Synthesis of 5a: A preseasoned FEP tube (6 mm o.d.) was charged,
in the dry box, with 4 (0.100 g, 0.13 mmol). The apparatus was
reconnected to the line and the connectors were passivated. Dichlo-
romethane (0.8 mL) was condensed into the reaction tube at
–196 °C under a static vacuum. The tube was warmed to –78 °C
and placed under carbon monoxide (2 atm) and slowly warmed to
room temperature. The reaction vessel was left to stand for 3 h
with occasional agitation after which all the solid had dissolved.
All volatiles were removed under reduced pressure to give 5a as an
off-white solid (0.092 g, 89%). See Table 1 for spectroscopic data.
Synthesis of 5b: A preseasoned FEP tube (6 mm o.d.) was charged,
in the dry box, with 4 (0.100 g, 0.13 mmol) and triphenylphosphane
(0.367 g, 0.14 mmol, 1.1 equiv.). The apparatus was reconnected to
the line and the connectors were passivated. Dichloromethane
(0.8 mL) was condensed into the reaction tube at –196 °C under a
static vacuum. The tube was warmed to room temperature and left
for 2 h with occasional agitation. All volatiles were removed under
reduced pressure to give an off-white solid, which was washed with
warm hexane to give 5b (0.108 g, 81%). See Table 1 for spectro-
scopic data.
Dicarbonylbis(triphenylphosphane)ruthenium difluoride (1a),[11a]
dicarbonylbis(ethyldiphenylphosphane)ruthenium
difluoride
(1b),[11a]
dicarbonylbis(phenylethynyldiphenylphosphane)ruthe-
nium difluoride (1c)[11c] and bis{1,3-bis(2,6-diisopropylphenyl)-
imidazol-2-ylidene}dicarbonylruthenium difluoride (1d)[12] were
prepared according to previously reported procedures. All other
chemicals were obtained commercially and used without further
purification.
Synthesis of 6: A preseasoned FEP tube (6 mm o.d.) was charged,
in the dry box, with 1a (0.250 g, 0.347 mmol). The apparatus was
reconnected to the line and the satellite connectors were passivated.
Dichloromethane (2 mL) was condensed into the vessel at –196 °C
and the solution was warmed to ambient temperature whereupon
dissolution of the solid occurred. The resulting yellow solution was
cooled to –50 °C and placed under PF5 (1.3 atm). The reaction
vessel was closed and the reaction mixture was stirred and warmed
Synthesis of 2: A Schlenk vessel was charged, in a dry box, with
1a (0.250 g, 0.347 mmol) and acetonitrile (20 mL) was introduced.
BF3·OEt2 (1 mL, excess) was added dropwise to the stirred solution
at room temperature forming a colourless solution. After stirring
at room temperature for 10 h, all volatiles were removed under re-
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Routes to Ruthenium–Fluoro Cations
(cautiously) to room temperature. The yellow solution was recooled
to –50 °C and PF5 was reintroduced and the uptake of the gas
monitored. This process was repeated until the consumption of PF5
had ceased. All volatiles were removed under reduced pressure to
were removed under reduced pressure to give [RuF(CO)2(PPh2Et)2]-
[FB(C6F5)3] (8b) as an air- and moisture-sensitive white powder
(0.173 g, 95%). C48H30BF17O2P2Ru·2CH2Cl2 (1304.80): calcd. C
46.00, H 2.60; found C 46.14, H 1.95. FAB mass spectrum, m/z =
give [RuF(CO)2(PPh3)2](PF6) (6) as an air- and moisture-sensitive (–FAB) 531 [FB(C F ) ]. IR (solid state): ν = 3357 (w), 2962 (w),
˜
6
5 3
yellow powder (0.280 g, 97%). FAB mass spectrum, m/z = (–FAB)
2066 (s, CO), 2005 (s, CO), 1641 (s), 1512 (s), 1459 (s), 1257 (s),
1092 (br), 1014 (br), 966 (br), 792 (s) cm–1. See Table 1 for ad-
ditional spectroscopic data.
145 (PF ). IR (solid state): ν = 2073 (s, CO), 2006 (s, CO), 1479
˜
6
(s), 1432 (s), 1094 (s), 831 (br), 741 (s), 688 (s) cm–1.
Synthesis of 7: A Schlenk vessel was charged, in a dry box, with 6
(0.200 g, 0.237 mmol), potassium tetra(3,5-bistrifluoromethyl-
phenyl)borate (0.214 g, 0.237 mmol) and dichloromethane (10 mL)
were then introduced. The reaction mixture was stirred at ambient
temperature for 5 h. Following filtration, carbon monoxide was
bubbled through the stirred solution at room temperature for
30 min. The resulting clear solution was transferred to a vessel con-
taining diethyl ether (200 mL) and the resulting precipitate isolated
by filtration. Recrystallistion from dichloromethane/hexane (1:100)
afforded 7 as air- and moisture-sensitive white crystals (0.285 g,
75%). Single crystals suitable for an X-ray diffraction study were
grown by slow diffusion of hexane into a saturated dichlorometh-
ane solution of 7. C71H42BClF24O3P2Ru·0.5CH2Cl2 (1650.3): calcd.
C 52.00, H 2.60; found C 52.00, H 2.59. FAB mass spectrum, m/z
(ii) L = P(CCPh)Ph2 (8c): The title complex was isolated in a sim-
ilar manner to that used for 8b, using 1c (0.200 g, 0.262 mmol) and
tris(pentafluorophenyl)borane (0.133 g, 0.261 mmol). Removal of
all volatiles under reduced pressure gave [RuF(CO)2(PPh2CCPh)2]-
[FB(C6F5)3] (8c) as an air- and moisture-sensitive white powder
(0.32 g, 96%). C60H30BF17O2P2Ru (1278.80): calcd. C 56.29, H
2.35; found C 56.29, H 2.29. FAB mass spectrum, m/z = (–FAB)
531 [FB(C F ) ]. IR (solid state): ν = 3010 (br), 2177 (s, CϵC),
˜
6
5 3
2070 (s, CO), 2005 (s, CO), 1509 (s), 1461 (s), 1279 (s), 1091 (br),
965 (w), 739 (s) cm–1. See Table 1 for additional spectroscopic data.
(iii) L = IPr (8d): The title complex was isolated in a similar manner
to that used for 8b, using 1c (0.253 g, 0.261 mmol) and tris(pen-
tafluorophenyl)borane (0.133 g, 0.261 mmol). Removal of all vola-
tiles under reduced pressure gave [RuF(CO)2(IPr)2][FB(C6F5)3] (8d)
as an air- and moisture-sensitive white powder (0.352 g, 91%).
C74H72BF17N4O2Ru·3CH2Cl2 (1737.80): calcd. C 53.16, H 4.48, N
3.22; found C 53.63 H 4.75, N 2.89. FAB mass spectrum, m/z =
= (–FAB) 863 {[B(ArF) ]}. IR (solid state): ν = 2073 (s, CO), 2011
˜
4
(s, CO), 1435 (s), 1351 (s), 1270 (vs), 1131 (br), 881 (s) cm–1.
Synthesis of 8: (i) L = PEtPh2 (8b): A preseasoned FEP tube (6 mm
o.d.) was charged, in the dry box, with 1b (0.100 g, 0.161 mmol)
and tris(pentafluorophenyl)borane (0.82 g, 0.161 mmol). The appa-
ratus was reconnected to the line and the satellite connectors were
passivated. Dichloromethane (3 mL) was condensed into the vessel
at –196 °C and the solution warmed to ambient temperature where-
upon dissolution of the solid occurred. After stirring the resulting
colourless solution at room temperature overnight, all volatiles
(–FAB) 531 [FB(C F ) ]. IR (solid state): ν = 2966 (w), 2063 (s,
˜
6
5 3
CO), 2011 (s, CO), 1510 (s), 1454 (br), 1275 (s), 1088 (br), 959 (w),
801 (s), 756 (s) cm–1. See Table 1 for additional spectroscopic data.
Synthesis of 9: Carbon monoxide was bubbled through a stirred
solution of 8d (0.200 g, 0.132 mmol) in dichloromethane (5 mL) for
30 min. Removal of all volatiles under reduced pressure afforded a
Table 6. Crystallographic and data processing parameters for 2, 3, 5a/3, 7 and 9[a]
.
2
3
5a/3
7
9
Empirical formula
Mr [gmol–1
Crystal size [mm]
C
42H36B3F11N2O2P2Ru C40H30B2F8O4P2Ru C78H60B3F14O6P4Ru2 C71.5H43BCl2F24O3P2Ru C75H172BF17N4O3Ru
]
1005.17
0.37ϫ0.12ϫ0.05
150(2)
911.27
1717.71
0.21ϫ0.07ϫ0.04
150(2)
1650.78
1512.25
0.26ϫ0.20ϫ0.14
150(2)
0.12ϫ0.10 ϫ0.06
150(2)
0.06ϫ0.15ϫ0.20
150(2)
Temperature [K]
Crystal system
Space group
a [Å]
b [Å]
c [Å]
monoclinic
P21/c
21.865(3)
9.8073(15)
20.139(3)
90
92.785(3)
90
4313.5(11)
4
triclinic
P1
monoclinic
C2/c
22.614(12)
13.342(12)
12.807(8)
90
101.329(15)
90
3789(4)
2
triclinic
P1
monoclinic
Cc
18.227(6)
23.267(6)
16.982(5)
90
102.298(7)
90
7037(3)
4
¯
¯
10.2154(18)
10.904(2)
11.313(2)
113.046(2)
99.606(3)
95.918(3)
1123.4(4)
1
13.321(3)
18.143(4)
18.330(4)
107.813(4)
104.632(4)
110.705(4)
3607.1(13)
2
α [°]
β [°]
γ [°]
U [Å3]
Z
Dc [Mgm–3
]
1.548
1.347
1.506
1.520
1.427
F(000)
2024
0.524
30094
7598
458
0.489
8172
3923
1730
0.570
14310
3726
1650
0.444
26234
12583
3104
0.319
27059
13525
µ(Mo-Kα) [mm–1
Reflections collected
Independent reflections
Rint
]
0.0568
0.0276
0.0870
0.1576
0.0934
Restraints/parameters
Final R indices
[IϾ2σ(I)]
0/570
0/229
0/247
0/884
2/401
R1 = 0.0465
wR2 = 0.1028
R1 = 0.0671
wR2 = 0.1101
R1 = 0.1057
wR2 = 0.3029
R1 = 0.1118
wR2 = 0.3133
1.378
R1 = 0.0747
wR2 = 0.1782
R1 = 0.1098
wR2 = 0.1915
1.108
R1 = 0.0960
wR2 = 0.1860
R1 = 0.2487
wR2 = 0.2399
0.863
R1 = 0.1008
wR2 = 0.2522
R1 = 0.1232
wR2 = 0.2764
1.027
All data
Goodness of fit on F2 (all data) 1.000
2
2 2
2
[a] Data in common: R1 = Σ||Fo| – |Fc||/Σ|Fo|, wR2 = {Σ[w(Fo – Fc ) /Σw(Fo2)2]}1/2, w–1 = [σ2(Fo)2 + (aP)2], P = [max(Fo2,0) + 2(Fc )]/3,
where a is a constant adjusted by the program; goodness of fit = [Σ(Fo – Fc ) /(n – p)]1/2 where n is the number of reflections and p the
2
2 2
number of parameters.
Eur. J. Inorg. Chem. 2010, 4130–4138
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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4137

E. G. Hope, G. A. Solan et al.
FULL PAPER
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white solid, which was recrystallised from dichloromethane/hexane
affording [RuF(CO)2(IPr)2][FB(C6F5)3] (8d) as an air- and moist-
ure-sensitive white powder (0.192 g, 94%). Single crystals suitable
for an X-ray diffraction study were grown by diffusion of hexane
[9]
vapour into
a
saturated dichloromethane solution of 9.
C75H72BF17N4O3Ru (1510.80): calcd. C 59.56, H 4.76, N 3.71;
found C 59.72, H 4.94, N 3.75. FAB mass spectrum, m/z = (–FAB)
[10]
531 [FB(C F ) ]. IR (solid state): ν = 2969 (s), 2062 (s, CO), 2011
˜
6
5 3
(s, CO), 1513 (s), 1457 (vs), 1275 (s), 1088 (s), 962 (s), 750 (s), 671
(s) cm–1. See Table 1 for additional spectroscopic data.
Crystallographic Studies: Data collections for 2, 3, 5a/3, 7 and 9
were carried out with a Bruker APEX 2000 CCD diffractometer
using graphite-monochromated Mo-Kα radiation (λ = 0.71073 Å).
Details of the data collection, refinement and crystal data are listed
in Table 6. The data were corrected for Lorentz and polarization
effects and empirical absorption corrections were applied. Structure
solution by direct methods and structure refinement on F2 em-
ployed SHELXTL version 6.10.[24] Hydrogen atoms were included
in calculated positions (C–H: 0.93–0.98 Å) riding on the bonded
atom with isotropic displacement parameters set to 1.5Ueq(C) for
methyl H atoms and 1.2Ueq(C) for all other H atoms. All non-H
atoms, apart from the disordered fluorine substituents in the CF3
groups of the anion in 7 and the disordered CO/F groups in 5a/3,
were refined with anisotropic displacement parameters. Data was
also collected for 9 but did not prove stable to full anisotropic re-
finement (see Supporting Information).
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Acknowledgments
We acknowledge the Engineering and Physical Sciences Research
Council (EPSRC) for financial support.
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Received: April 14, 2010
Published Online: August 16, 2010
4138
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Eur. J. Inorg. Chem. 2010, 4130–4138