Carbon-fluorine bond activation in thermolysis reactions of the osmium(IV) perfluorothiolate compounds [Os(SC6F5) 4(P(C6H4X-4)3)] (X = CF3, Cl, F, H, CH3, and OCH3)

Article abstract of DOI:10.1021/om901065g

Thermolysis reactions of [Os(SC₆F₅) ₄(P(C₆H₄X-4)₃)] (X = CF₃ 1, Cl 2, F 3, H 4, CH₃ 5, and OCH₃ 6) in refluxing toluene yield compounds [OsF(SC₆F₅)₂(SC ₆F₄(SC₆F₅)-2)(P(C₆H ₄X-4)₃)] (1a-6a) and [Os(SC₆F₅) ₂(SC₆F₄(SC₆F₅)-2)(C ₆H₄X-4)] (1b-6b). In addition, [Os(SC₆F ₅)₃(SC₆F₄(SC₆F ₅)-2)] (c) is yielded from 1-4 and 6, compounds [OsF(SC ₆F₅)₃(P(C₆H₄X-4) ₃)] [X = CF₃ (1e), X = Cl (2e)] are also identified as products of the thermolysis reactions of 1 and 2, while [Os(SC₆F ₅)₂(S₂C₆F₄)(P(C ₆H₄CH₃-4)₃)] (5d) is obtained from 5. Compounds c, e, and d are produced in low yields (ca. 2-4%). Formation of all products involves the rupture of ortho C-F bonds. The first complexes systematically detected in these thermolysis reactions are compounds a, which are isomers of the starting complexes. Thus, the C-F activation involves the metal-mediated generation of the covalent Os-F bond. Single-crystal X-ray diffraction studies of the new compounds 4a, 5a, 2b-6b, 2e, and 5d indicate that these compounds consist of five-coordinated metal ions in essentially trigonal-bipyramidal geometries. In addition, thermolysis of the isolated compound [OsF(SC₆F₅)₂(SC₆F ₄(SC₆F₅)-2)(P(C₆H₄CH ₃-4)₃)] (5a) in refluxing toluene gives rise to [Os(SC₆F₅)₂(SC₆F₄(SC ₆F₅)-2)(C₆H₄CH₃-4)] (5b) and [Os(SC₆F₅)₂(S₂C ₆F₄)(P(C₆H₄CH₃-4) ₃)] (5d), confirming that compounds a can generate compounds b when the thermolysis is prolonged. Compounds 1a-6a, 2b-6b, 1e, and 2e are investigated in solution by NMR studies, including variable-temperature ¹⁹F NMR experiments. These molecules are fluxional. Some of the activation parameters for the dynamic processes are determined.

Full text of DOI:10.1021/om901065g

2646 Organometallics 2010, 29, 2646–2659
DOI: 10.1021/om901065g
Carbon-Fluorine Bond Activation in Thermolysis Reactions of the
Osmium(IV) Perfluorothiolate Compounds [Os(SC6F5)4(P(C6H4X-4)3)]
(X = CF3, Cl, F, H, CH3, and OCH3)
†
Consuelo Mendoza, Sylvain Bernes, Hugo Torrens, and Maribel Arroyo*
‡
§
,†
ꢀ
†
´
Centro de Quımica, Instituto de Ciencias, BUAP, Ciudad Universitaria, San Manuel, 72570 Puebla,
‡
Puebla, Mexico, DEP, Facultad de Ciencias Quımicas, UANL, Guerrero y Progreso S/N,
´
Col. Trevin~o 64570 Monterrey, Nuevo Leoꢁn, Mexico, and DEP, Facultad de Quımica, UNAM,
ꢁ
Ciudad Universitaria, 04510 Mexico D.F., Mexico
§
´
Received December 11, 2009
Thermolysis reactions of [Os(SC6F5)4(P(C6H4X-4)3)] (X=CF3 1, Cl 2, F 3, H 4, CH3 5, and OCH3 6)
in refluxing toluene yield compounds [OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4X-4)3)] (1a-6a) and
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4X-4)] (1b-6b). In addition, [Os(SC6F5)3(SC6F4(SC6F5)-2)] (c) is
yielded from 1-4 and 6, compounds [OsF(SC6F5)3(P(C6H4X-4)3)] [X=CF3 (1e), X=Cl (2e)] are
also identified as products of the thermolysis reactions of 1 and 2, while [Os(SC6F5)2(S2C6F4)-
(P(C6H4CH3-4)3)] (5d) is obtained from 5. Compounds c, e, and d are produced in low yields
(ca. 2-4%). Formation of all products involves the rupture of ortho C-F bonds. The first com-
plexes systematically detected in these thermolysis reactions are compounds a, which are isomers
of the starting complexes. Thus, the C-F activation involves the metal-mediated generation of
the covalent Os-F bond. Single-crystal X-ray diffraction studies of the new compounds 4a,
5a, 2b-6b, 2e, and 5d indicate that these compounds consist of five-coordinated metal ions
in essentially trigonal-bipyramidal geometries. In addition, thermolysis of the isolated com-
pound [OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4CH3-4)3)] (5a) in refluxing toluene gives rise to
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4CH3-4)] (5b) and [Os(SC6F5)2(S2C6F4)(P(C6H4CH3-4)3)] (5d),
confirming that compounds a can generate compounds b when the thermolysis is prolonged.
Compounds 1a-6a, 2b-6b, 1e, and 2e are investigated in solution by NMR studies, including
variable-temperature 19F NMR experiments. These molecules are fluxional. Some of the activation
parameters for the dynamic processes are determined.
Introduction
attained.2-22 Catalytic or stoichiometric C-F bond func-
tionalization, where a fluorine atom in an organic molecule
is replaced by a new group through a metal-mediated
reaction, has been reported for the conversion of C-F
bonds to C-H bonds (hydrodefluorinations),4,13,22-24
Developments in metal-mediated C-F bond activation
have been reviewed,1 and relevant recent advances have been
*Corresponding author. E-mail: slarroyo@siu.buap.mx.
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2010 American Chemical Society

Article
Organometallics, Vol. 29, No. 12, 2010 2647
C-C bonds (CC coupling reactions),6,8,15-17,19,20 C-O or
CdO bonds,10,14,25-28 C-Si bonds,18 and C-B bonds (C-F
bond borylation).2,9
phosphane substituent with F are relevant for C-F bond
activation and have been recently reviewed by Macgregor.34
Although rare, a number of well-defined examples of P-C/F
exchange have been published, where a phosphane substi-
tuent is transferred from phosphorus to metal with the
formation of the fluorophosphane complex. Experimental
and computational mechanistic studies have examined the
pathways involved in these reactions. These processes result
in a net P-C/F exchange reaction, although this is some-
times masked by subsequent reactivity of the initial exchange
product. For example, one of the first reports of this type
describes the reaction of C6F6 with [Ir(CH3)(PEt3)3] that
resulted in a process involving C-F bond cleavage, P-C
bond cleavage, and P-F bond formation, yielding the com-
plex trans-[Ir(C6F5)(PFEt2)(PEt3)2].35 In this case not only
the P-C/F exchange was involved but also the elimination of
ethene and methane. Recent computational studies36 of this
reaction have shown that the phosphane ligands play an
active role in this novel “phosphane-assisted” C-F activa-
tion process, involving nucleophilic attack of the electron-
rich organometallic on the C6F6 and trapping of the
displaced fluoride by a phosphane ligand to form a five-
coordinated metallophosphorane intermediate. In other
studies of C-F bond activation, the reaction of pentafluoro-
pyridine with [Pt(PR3)2] (R = cyclohexyl, isopropryl) in
THF led to the unusual P-C/F exchange products [PtR-
(4-C5NF4)(PFR2)(PR3)], while the corresponding reactions
with [Pd(PR3)2] yielded the classic C-F oxidative addition
products [PtF(4-C5NF4)(PR3)2].37 Analogous P-C/F chem-
istry was observed for the reaction of C6F6 with [Pt(PR3)2]
and [Pd(PR3)2].38 Another P-C/F process was observed
when [RhF(PPh3)3] was heated in chlorobenzene to give
the fluorophosphane complex trans-[RhCl(PFPh2)(PPh3)2]
and biphenyl.39 Mechanistic studies identified cis-[RhPh-
(PFPh2)(PPh3)2] as an intermediate, while kinetic studies
showed that this species is formed via an intramolecular P-
Ph/F exchange process.38 DFT studies on the full [RhF-
(PPh3)3] system40 showed a clear preference for a pathway
where the fluorine atom acts as an intramolecular nucleo-
phile to give the five-coordinate metallophosphorane
intermediate from which Ph migration to Rh completes the
P-C/F exchange.
C-F bond activation by osmium complexes is rare.29-33
In the presence of fluoride as a catalyst, Me3SiCF3 exchanges
CF3 with the fluoride in the complex [OsHF(CO)L2] (L =
PiPr3, PtBu2Me) to form the (difluorocarbene)(fluoro) com-
plex [OsHF(CF2)(CO)L2] via R-fluorine migration. This
complex converts to [OsF2(CFH)(CO)L2], resulting from
exchange of one carbene fluoride with the hydride. Thus,
the final osmium complex arises from a double R-fluorine
migration.31 Barrio and co-workers reported30 that the
hexahydride-osmium complex [OsH6(PiPr3)2] reacts with
fluorinated aromatic ketones in refluxing toluene to yield
products involving the activation of ortho C-H and ortho
C-F bonds on the aromatic ketones. For example, ortho
C-F activation is preferred over ortho C-H activation
for the reaction with 2,3,4,5,6-pentafluorobenzophenone to
give the seven-coordinate complex [OsH3{C6F4(CO)C6H5}-
(PiPr3)2], and the corresponding reactions with pentafluor-
oacetophenone, decafluorobenzophenone, and 2,6-difluor-
oacetophenone to give [OsH3{C6F4(CO)R}(PiPr3)2] (R =
CH3, C6F5) and [OsH3{C6H3F(CO)CH3}(PiPr3)2], respec-
tively. [OsH3Cl(PiPr3)2] reacts with CH2dCHF within the
time of mixing to produce [OsHFCl(tCCH3)(PiPr3)2] and
H2.29 Previously, we found32,33 that the thermolysis reaction
of the osmium(III) complex [Os(SC6F5)3(PMe2Ph)2] in re-
fluxing toluene causes cleavage of ortho C-F bonds, afford-
ing [Os(SC6F5)2(S2C6F4)(PMe2Ph)] and [Os(C6F5)2(S2C6F4)-
(PMe2Ph)2], but no Os-F complex was observed, and the fate
of the exchanged fluorine atom remained unknown.
On the other hand, processes in transition metal-pho-
sphane complexes that result in the unusual replacement of a
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2648 Organometallics, Vol. 29, No. 12, 2010
Mendoza et al.
Scheme 1
reactions, rather than the desired Ar-F reductive elimina-
tion. The fluorine-containing phosphorus products from
reactions of these fluoro complexes have been identified as
fluorophosphane coordinated to the metal or other uncoor-
dinated fluorine-containing phosphorus products.41
Scheme 2
A recent contribution to the development of aromatic
C-F substitution reactions is the transition metal catalytic
derivatization of C-F to C-S bonds.7 In the presence of
[RhH(PPh3)4], 1,2-(Ph2P)2C6H4, and PPh3, substituted
fluorobenzenes, XnC6H5-nF, react with disulfides (RSSR)
to give the sulfides XnC6H5-nSR. PPh3 traps the fluorine to
form PPh3F2. It was presumed that the fluoride transfer took
place from the rhodium to the phosphorus atom of PPh3.
The authors suggested that the rhodium complex was in-
volved in the cleavage of the C-F bond in the aryl fluorides
and the S-S bond in the disulfides. The mode of C-F bond
cleavage was a subject of interest, and nucleophilic aromatic
substitution of the aryl fluoride with rhodium thiolate was
proposed as a possible pathway. The authors emphasize that
this rhodium-catalyzed method contains a notable mode of
C-F activation by a transition metal catalyst and may offer
an extremely broad scope for the manipulation of organo-
sulfur compounds.
and Os-F bonds. The results presented here contribute to our
comprehension of the derivatization mechanism of fluorinated
aryl groups via C-F activation and C-S bond formation at
a transition metal center. Furthermore, fluoride complexes
appear as key intermediates in catalytic cycles,20 and therefore,
investigations into the reactivity of these intermediates will
improve our understanding and encourage further develop-
ment of the functionalization of polyfluoroorganics.
Here, we report a work centered on (phosphane)(fluoro-
thiolate)osmium(IV) complexes, from which thermolysis
reactions in refluxing toluene involves C-F bond activation
with C-S bond formation to generate new complexes with a
sulfide ligand and an Os-F bond as the first observed and
isolated complexes. In addition, we have examined the
products of subsequent rearrangements. Thus, heating in
refluxing toluene causes the molecules of the starting com-
pound to experience a series of complex rearrangements to give
always well-defined products. The formation of all products
involves the rupture of ortho C-F bonds from the original
SC6F5 rings in the starting material, cleavage of P-C, C-S,
Os-S, and Os-P bonds, and generation of new C-S, Os-C,
Results and Discussion
C-F bonds are broken during the thermolysis reactions
of the osmium(IV) compounds [Os(SC6F5)4(P(C6H4-
X-4)3)] (X = CF3 1, Cl 2, F 3, H 4, CH3 5, and OCH3 6)42
in refluxing toluene. The isolated products of these reactions
are [OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4X-4)3)] (1a-6a),
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4X-4)] (2b-6b), and the
persulfured compound [Os(SC6F5)3(SC6F4(SC6F5)-2)] (c) pre-
viously reported25 (Scheme 1), except for the reaction from 5,
which yields compounds 5a, 5b, and [Os(SC6F5)2(S2C6F4)-
(P(C6H4CH3-4)3)] (5d) (Scheme 2).
TLC analysis showed that the first products observed after
1-2 h under reflux are compounds a. Compounds b and c are
detected 1-3 h after compounds a appear. Yields of isolated
compounds a varied between 20% and 50% after 6 h reaction
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Article
Organometallics, Vol. 29, No. 12, 2010 2649
Scheme 3
times. These yields are notably reduced when the reaction time
is prolonged to increase the yields of compounds b. The yields
of compounds b were 10-14% after 20h reaction times. Inthe
reaction from 5 (X=CH3), where compound c is not detected,
compound 5d is observed instead, after 13 h of reaction time.
Compounds c and d are produced in very low yields (2-4%).
Note that compounds 1a-6a are isomers of their corre-
sponding starting complexes 1-6. Thermolysis reaction of
the isolated compound [OsF(SC6F5)2(SC6F4(SC6F5)-2)-
(P(C6H4CH3-4)3)] (5a) in refluxing toluene gives rise to
compounds [Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4CH3-4)] (5b)
and [Os(SC6F5)2(S2C6F4)(P(C6H4CH3-4)3)] (5d) (Scheme 3).
This result is consistent with the TLC results and suggests that
compounds a are the initial products and that compounds b, as
well as compounds c and d, likely arise from compounds a.
All these metallic reaction products were isolated by
column chromatography.
In solution, compounds a are air-sensitive, and therefore
their solutions were immediately evaporated under vacuum
or stored under argon. The crystallization of 4a and 5a was
carried out by a slow argon flux over hexane-CH2Cl2 (1:9)
solutions. The isolation of compounds b was difficult due to
the similar retention factors of compounds b and c (or 5d)
and unreacted starting material. However, reasonable iso-
lations of compounds b-d were attained, as supported by
the analytical data and NMR spectra. Compounds b, c, and
5d were crystallized from air-stable hexane-CH2Cl2 (4:1)
solutions.
The reaction from compound 5 (X = CH3) yields 5d
instead of c, but there was no evidence to indicate the reason
for this difference. The yield of compound 5d is so low that it
is probable that the level of possible compounds 1d, 2d, 3d,
4d, and 6d was undetectable.
Figure 1. Molecular structure of compound 4a with displace-
ment ellipsoids at the 25% probability level. H atoms have been
omitted for clarity. Main metric parameters (A, deg): Os1-P1
2.3256(17), Os1-S1 2.2051(18), Os1-S3 2.1991(16), Os1-S4
2.2070(18), Os1-F1 2.041(3); P1-Os1-F1 178.79(10).
corresponding to losses of different groups from the molecular ion
including [M - C6H4X]þ (3-42%), [M - (SC6F5)]þ (3-44%),
[M - (SC6F5) - (C6H4X)]þ (8-80%), and [M - (SC6F5) -
(C6H4X) - (C6F5)]þ (2-26%).
The
FABþ
mass
spectra
of
compound
[Os(SC6F5)3(SC6F4(SC6F5)-2)] (c) are as previously reported.25
The corresponding FABþ mass spectrum of compound
[Os(SC6F5)2(S2C6F4)(P(C6H4CH3-4)3)] (5d) showed the sig-
nal of the molecular ion [M]þ (38%). The loss of SC6F5 is
also observed (12%) as well as successive losses of C6F5 and
H to generate [M - (SC6F5) - (C6F5) - H)]þ (10%). Other
fragments of lower intensities were also observed.
Single-crystal X-ray diffraction studies of compounds
4a-5a, 2b-6b, and 5d indicated a common coordination
geometry that resembles trigonal-bipyramidal geometry,
with the equatorial plane containing three S atoms. Com-
pounds a, b, and d have different axial components:
P(phosphane) and F in compounds a, S and C(aryl) in
compounds b, and S and P(phosphane) in compound 5d.
The products were characterized by elemental analysis,
FABþ mass spectrometry, and NMR and IR spectroscopy.
The FABþ mass spectra of all compounds [OsF(SC6F5)2-
(SC6F4(SC6F5)-2)(P(C6H4X-4)3)] (a) show signals corre-
sponding to [M - F]þ ions with intensities of 18-95%.
[M - SC6F5]þ ions were present with intensities of 14-90%.
Signals corresponding to [M - (SC6F4(SC6F5))]þ (3 -19%),
[M - F - (SC6F5) - (P(C6H4X-4)3)]þ (1-15%), [M - F -
(SC6F5) - (P(C6H4X-4)3) - (C6F5)]þ (2-18%), and
[P(C6H4X-4)3]þ (100%) were also detected.
The FABþ mass spectra of all compounds
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4X-4)] (b) showed signals
corresponding to the parent ions [M]þ (1-17%) and signals

2650 Organometallics, Vol. 29, No. 12, 2010
Mendoza et al.
The Os-F bond has been described previously43-45 and
has been X-ray measured in Os(IV) compounds, mainly in
octahedral anions [OsF6]2- and [OsCl2F4]2- and analogous
hexahalide ions.44,45 Bond lengths measured for compounds
4a (2.041(3) A) and 5a (2.060(3) A) are longer than those
previously reported (ca. 1.92 A).44,45 This is to be expected
due to the stronger trans influence of phosphane compared
to halide ions. Thus, the fluoride ion in compounds 4a and
5a is likely weakly bonded to the metal center. The mono-
coordinated thiolate-thioether ligand in 4a and 5a is placed
in the opposite hemisphere of the phosphane, in an arrange-
ment resembling the starting complex.46,42 In compounds
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4X-4)3)] (4a, X = H;
5a, X = CH3), the Os-P bond length (2.3256(17) and
2.3348(15) A, respectively) is shorter than the Os-P bond
length in their respective starting compounds 4 (2.403(2) to
2.410(2) A)46 and 5 (2.4035(14) A).42 This shorter bond
length reflects the weaker trans influence of the fluoride
ligand relative to the thiolate ligand.
Except for 1b, all b compounds have been characterized
by X-ray analysis. The thiolate-thioether ligand, which
was monocoordinated in compounds a, is now a chelating
ligand, as it is in compound c, which we previously
described.25 In the trans position from the Sthioether atom,
an axial aryl group provided by the phosphane of the
starting material is coordinated through a C atom, with
Os-C bond lengths in the range 2.098(16)-2.112(3) A.
These Os-C bonds are longer than other Os(IV)-C bonds
reported in the literature.47 The trigonal-bipyramidal co-
ordination geometry is completed by two thiolates, with
their substituents arranged in an anti configuration rela-
tive to the equatorial plane. A configuration with both
thiolate substituents oriented toward the hemisphere con-
taining the thiolate-thioether ligand is unlikely, as the four
perfluorinated rings would be sterically hindered. Con-
versely, an arrangement with both thiolate substituents
placed in the other hemisphere seems to be at least as stable
as the crystallized configuration.
Figure 2. Molecular structure of compound 2b with displace-
ment ellipsoids at the 25% probability level. H atoms have
been omitted for clarity. Main metric parameters (A, deg): Os1-
S1 2.4465(12), Os1-S2 2.1877(13), Os1-S3 2.2058(13), Os1-S4
2.2144(14), Os1-C25 2.109(5); S1-Os1-C25 177.06(15).
In compounds [Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4X-4)]
(2b-6b), the distance Os-Sthioether(axial) (2.445(4)-2.4532(10)
A) islonger thanthe distanceOs-Sthioether(axial) (2.3739(13) A)
in compound [Os(SC6F5)3(SC6F4(SC6F5)-2)] (c),25 reflecting
the greater trans influence of the C6H4X-4 ligand relative to
the SC6F5 ligand.
A remarkable characteristic of compounds 2b-6b is their
similarity in structure. Regardless of the identity of the
phosphane present in the thermolyzed complex, the b com-
pounds have identical ligand arrangements and almost
identical molecular structures.
Finally, compound 5d is analogous to a previously char-
acterized Os(IV) compound bearing dimethylphenylphosp-
hane32,33 in place of tris-p-tolylphosphane. The 1,2-dithio-
late-perfluorobenzene ligand acts as a chelate, with two
S atoms occupying axial and equatorial positions, as the
Figure 3. Molecular structure of compound 5d with displace-
ment ellipsoids at the 25% probability level. H atoms have been
omitted for clarity. Main metric parameters (A, deg): Os1-P1
2.386(2), Os1-S1 2.382(2), Os1-S2 2.190(2), Os1-S3 2.224(2),
Os1-S4 2.225(2); P1-Os1-S1 175.73(8).
ORTEP-style views are shown for compounds 4a, 2b, and 5d
in Figures 1-3. However, regardless of the axial compo-
nents, the trans angles remain close (175.17(9)-178.79(10)°)
to the ideal value of 180°. All compounds also crystallize in a
single space group, P1, with similar cell parameters, indicat-
ing that the general shape of the molecules is not dependent
on the exact nature of the ligands and that the molecules are
packed at the solid-state van der Waals distances without
significant intermolecular interactions.
(43) Ang, H. G.; Ang, S. G.; Leong, W. Y.; Winfield, J. J. Fluorine
Chem. 1998, 88, 5–8.
(44) Kuppers, H.; Gobel, O.; Bruhn, C.; Schmahl, W. W. Z. Kristallogr.
2001, 216, 354–360.
(45) Bruhn, C.; Preetz, W. Acta Crystallogr. 1996, C52, 321–325.
ꢀ
(46) Mendoza, C.; Bernes, S.; Arroyo, M. Acta Crystallogr. 2006,
C62, m201–m204.
(47) Eguillor, B.; Esteruelas, M. A.; Olivan, M.; Onate, E. Organo-
ꢁ
~
metallics 2004, 23, 6015–6024.

Article
Organometallics, Vol. 29, No. 12, 2010 2651
Figure 6. Plot of the Fax-chemical shift (δ) vs Tolman’s para-
meter50 for the phosphane (χ) in the compounds [OsF(SC6F5)2-
(SC6F4(SC6F5)-2)(P(C6H4X-4)3)] (1a-6a).
Figure 4. Drawing of [OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4-
X)3)] (X = H, 4a; X = CH3, 5a), as in the X-ray studies, showing
the different phenyl rings.
region. One group of three resonances is due to the ortho, para,
and meta fluorine atoms (relative intensities 4:2:4 at low,
medium, and high fields, respectively)49 from the two equiva-
lent -SC6F5 fragments (groups c, Figure 4). Another group of
three resonances is due to the ortho, para, and meta fluorine
atoms (relative intensities 2:1:2 at low, medium, and high fields,
respectively) from the C6F5 ring of the ligand -SC6F4SC6F5
(group b, Figure 4). A further group of four different reso-
nances (relative intensities 1:1:1:1) is due to the fluorines in the
C6F4 ring of the same -SC6F4SC6F5 ligand (group a, Figure 4).
In addition, all the spectra show a doublet at high field (relative
intensity 1) corresponding to the axial fluoro ligand coupled to
the trans phosphorus atom, 2JF-P in the range 148-158 Hz. At
lower fields, the spectra of compounds 1a (X=CF3) and 3a
(X = F) exhibit additional resonances due to the fluorinated
substituent on the phosphane ligand. A linear correlation is
observed between the chemical shift of the axial fluorine
and Tolman’s electronic parameter50 (χ) for the phosphane
(Figure 6), consistent with the higher field chemical shift (more
electronic protection) for the fluoro ligand trans to the more
basic phosphane (lower Tolman’s electronic parameter).
31P{1H} NMR Studies. As expected from the solid-state
formulation of compounds 4a and 5a (Figure 4), the room-
temperature 31P{1H} NMR spectra of compounds 1a-6a
exhibit a doublet signal due to magnetic coupling of the
phosphorus with the trans fluoro ligand.
NMR Studies of Compounds [OsF(SC6F5)3(P(C6H4X-4)3)]
(1e, X=CF3; 2e, X=Cl). 19F NMR Studies. The 19F NMR
spectra of compounds 1a (X=CF3) and 2a (X=Cl) exhibit
additional resonances arising from minority compounds
assigned to [OsF(SC6F5)3(P(C6H4CF3-4)3)] (1e) and [OsF-
(SC6F5)3(P(C6H4Cl-4)3)] (2e). For both spectra, in the region
of the axial fluorine, there is a second doublet (relative
intensities between the major and minor doublets are 8:1
and 7:1, respectively). In the fluorinated aromatic region
(Figure 7) there are three additional signals at low, medium,
and high fields attributed to the ortho, para, and meta fluo-
rine atoms (relative intensities ca. 6:3:6, respectively) of three
equivalent equatorial -SC6F5 ligands (see crystal structure
of 2e, Figure 8). In the CF3 region of the spectrum of
Figure 5. 19F NMR spectrum of [OsF(SC6F5)2(SC6F4(SC6F5)-2)-
(P(C6H5)3)] (4a) at 80 °C. The letter labels identify the signals
that correspond to the same type of fluorinated ring, including
the relative integrals.
thiolate-thioether ligand does in compounds b and c. Com-
pound 5d is related to the starting material [Os(SC6F5)4-
(P(C6H4Me-4)3)], having the same coordination core,
-
[OsS4P]. The only difference is that four thiolates (SC6F5
)
are coordinated in the starting complex, while compound 5d,
which appears after the thermolysis has been carried out over
a long time, has only three perfluorinated rings in the hemi-
sphere occupied by the fluorinated ligands.
As expected, in compound [Os(SC6F5)2(S2C6F4)(P(C6H4-
CH3-4)3)] (5d), where the phosphane is trans to a sulfur of the
dithiolate ligand, the Os-P bond length (2.386(2) A) is
longer than the corresponding Os-P bond length in com-
pounds 4a and 5a (2.3256(17) and 2.3348(15) A respectively),
where the phosphane is trans to a fluoro ligand.
Furthermore, in compounds 2b-6b and 5d, the Os-
Sequatorial distances are notably shorter than the Os-Saxial
distances, as expected for d4-osmium(IV) complexes.48
NMR Studies of Compounds [OsF(SC6F5)2(SC6F4(SC6F5)-
2)(P(C6H4X-4)3)] (1a-6a). 19F NMR Studies. At high temper-
atures, the 19F NMR spectra are as expected assuming that the
solid-state structure of compounds a (Figure 4) is retained in
solution and that all the C6F5 rings are free to rotate about their
C-S bonds. At 80 °Cthe19F NMR spectra recorded at 376 MHz
(Figure 5) exhibit 10 absorptions in the perfluorinated aromatic
ꢁ
(49) Bertran, A.; Garcıa, J.; Martin, E.; Sosa, P.; Torrens, H. Rev.
´
´
Soc. Quım. Mex. 1993, 37 (4), 185–191. Chem. Abstr., 1993, 122,
329084j.
ꢁ
(50) (a) Bartik, T.; Himmler, T.; Schulte, H.-G.; Seevogel, K.
J. Organomet. Chem. 1984, 272, 29–41. (b) Tolman, C. A. Chem. Rev. 1977,
77, 313–348. (c) Tolman, C. A. J. Am. Chem. Soc. 1970, 92, 2953–2956.
(48) Rossi, A. R.; Hoffmann, R. Inorg. Chem. 1975, 14, 365–374.

2652 Organometallics, Vol. 29, No. 12, 2010
Mendoza et al.
Figure 7. 19F NMR spectrum of the mixture of [OsF(SC6F5)2-
(SC6F4(SC6F5)-2)(P(C6H4CF3)3)] (1a) and [OsF(SC6F5)3(P(C6-
H4CF3)3)] (1e) at 80 °C. The top letters identify the compound
(a or e). The bottom letters identify the signals that correspond
to each fluorinated ring in compound 1a (same as in Figure 4) or
that correspond to the ortho, para, and meta fluorine atoms in
equivalent equatorial thiolates in compound 1e. The two CF3
signals at low field are omitted.
Figure 9. Variable-temperature 19FNMRspectraof [OsF(SC6F5)2-
(SC6F4(SC6F5)-2)(P(C6H4CH3-4)3)] (5a) on the ortho and meta
regions of thehSC6F5 ligands (c groups), including relative
integrals.
studies revealed the structure of the solvated complex
[OsF(SC6F5)3(P(C6H4Cl)3)] 1.38CH2Cl2. The main mole-
3
cule (Figure 8) displays a trigonal-bipyramidal coordination
geometry for the Os center and a 3-fold symmetry, with the
P-Os-F fragment lying on the crystallographic 3 axis. The
C6F5 groups of all three equatorial thiolates are oriented in
the direction of the F ligand (3-up orientation). The coordi-
nated F- ion, occupying an axial site, is thus located in a
claw-shaped cavity with C3 symmetry. The crystal contains
large voids of ca. 250 A3, which were assumed to be filled
with disordered CH2Cl2 molecules, used as a solvent in
crystallization. The lattice solvent content was estimated
through the SQUEEZE procedure. As the anion F- is
known as the ligand having the weakest trans influence, the
axial phosphane in 2e is strongly bonded to the metal center,
as reflected in the rather short bond length Os1-P1 =
2.332(3) A.
At room temperature, the COSY 19F-19F NMR spectra
of 1a-6a show couplings in the b-C6F5 ring and in the a-C6F4
ring. However, couplings corresponding to the signals of the
c-C6F5 rings are absent due to fluxional processes of these
groups. At -60 °C, the COSY 19F-19F NMR spectra show,
in addition, the couplings corresponding to the signals of the
c-C6F5 rings.
Figure 8. Molecular structure of compound 2e with displace-
ment ellipsoids at the 25% probability level. H atoms have been
omitted for clarity. Main metric parameters (A, deg): Os1-P1
2.332(3), Os1-S1 2.199(2), Os1-F1 2.055(6), P1-Os1-F1 180.
compound 1a, there is also a singlet corresponding to 1e
(relative intensities between the major and minor CF3 sing-
lets 8:1).
The formation of compound e is consistent with the
observation of compound c as products of a ligand redistri-
bution reaction between two molecules a. It is worth noticing
that the products c and e are both observed in similar low
yields, as the redistribution reaction suggests.
To investigate more about compounds 1e and 2e, which
have the same chromatographic retention factors as 1a and
2a, respectively, we have probed the recrystallization of the
mixture “2a þ 2e” and, after repeated attempts, with decompo-
sition of [OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4Cl)3)] (2a),
we obtained a single crystal, of which the X-ray diffraction
Spectra collected at room temperature are more complex
than those collected at 80 °C. Variable-temperature 19F
NMR analysis of compound 5a (X=CH3) gives interesting
results (Figures 9-11). As the temperature decreases, the
subspectra of the a and b rings of the -SC6F4SC6F5 ligand
remain essentially unchanged, whereas the subspectra of the
c rings of the two thiolate groups -SC6F5 experience several
modifications. Figure 9 shows that, as the temperature
decreases, the ortho (4) and meta (4) signals from the two c
rings collapse, each one giving rise to a pair of signals
(relative intensities 2:2 and 2:2) at 62 and 59 °C, respectively.

Article
Organometallics, Vol. 29, No. 12, 2010 2653
Figure 12. Drawing of [Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4X-
4)] (2b-6b), as in the solid state, showing the different phenyl
rings. Although the NMR absorptions are linked to the aro-
matic rings a, b, c, and d, except for the rigid ring a, no definitive
b, c, and d correspondence can be established.
the overlap of the two para c signals with the a signal (low
field) and b signal (high field) prevents differentiation of the
signals. The Fax resonance remains as only one doublet over
the range of temperatures examined (Figure 11).
Figure 10. Variable-temperature 19F NMR spectra of [OsF-
(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4CH3)3)] (5a) on the para
region of thehSC6F5 ligands (c groups), including relative
integrals.
The effect of temperature on the NMR spectra can be
explained with a molecule where, at high temperatures,
rotation around the S1-C bond (Figure 1) renders the c
rings chemically equivalent, and a free energy of activation
for this process was estimated to be ΔG‡=65 ( 2 kJ mol-1
from the variable-temperature NMR data. At lower tem-
peratures, the rotation around the S4-C (or S3-C) bond of
one c ring also becomes restricted, with an estimated ΔG‡=
58 ( 2 kJ mol-1. With a further decrease in temperature, the
rotation around the S3-C (or S4-C) bond of the another
c ring also becomes restricted, with an estimated ΔG‡=56 (
2 kJ mol-1
.
NMR Studies of Compounds [Os(SC6F5)2(SC6F4(SC6F5)-
2)(C6H4X-4)] (2b-6b). 19F NMR Studies. For compounds
2b-6b, the COSY 19F-19F NMR spectra at different tem-
peratures show four subspectra corresponding to three non-
equivalent C6F5 groups (b, c, and d rings, Figure 12) and one
C6F4 group (a ring, Figure 12). Figure 13 shows one of these
COSY spectra at -20 °C.
Figure 14 shows the 19F NMR spectra at -20 °C, RT,
and þ80 °C for compound 2b (X=Cl). At -20 °C, the three
subspectra of the groups C6F5 correspond to AA0BCC0 spin
systems (relative intensities 1:1:1:1:1), while the subspectrum
of the group C6F4 corresponds to an ABCD spin system
(relative intensities 1:1:1:1). Thus, at -20 °C, all the spectra
of compounds b exhibit 19 well-defined resonances of the
same intensity, except for compound 3b (X=F), which has
an additional resonance at lower field arising from the
fluorine atom of the C6H4F- ligand. At room temperature
the number of signals is maintained; however two ortho and
two meta signals are broad with low intensities, which are
arbitrarily assigned to ring c. At 80 °C, the spectra show only
one c ortho resonance (relative intensity 2, instead of two
signals 1:1 at lower temperatures), one c meta resonance
(relative intensity 2), one d ortho resonance (relative intensity
2), and one d meta resonance (relative intensity 2). These
spectra at 80 °C are consistent with free rotation about C-S
bonds in two C6F5 groups (c and d), but restricted rotation
for the third C6F5 group (b) and the chelating C6F4 group (a).
Figure 11. Full 19F NMR spectra of [OsF(SC6F5)2(SC6F4-
(SC6F5)-2)(P(C6H4CH3-4)3)] (5a) at 65, 35, 0, and -80 °C.
At 37 and 27 °C, the low-field peaks of these ortho and meta
groups, respectively, then collapse too, giving rise to new
pairs of signals (relative intensities 1:1:2 and 1:1:2). At lower
temperatures, the high-field peaks of these ortho and meta
groups then collapse to give new pairs of resonances (relative
intensities 1:1:1:1 and 1:1:1:1). Analysis of the c para zone is
more complicated due to the proximity of one reasonance
a on the low-field side and one resonance b on the high-
field side (Figure 10). At high temperature (80 °C) the para
c resonance is a broad triplet. As the temperature decreases,
the broad triplet becomes a broad singlet at about 59 °C and
then collapses into two broad singlets at a temperature
somewhere between 59 and 40 °C. At 40 °C, the high-field
broad para c singlet overlaps one resonance b. From 27 to
15 °C, the lowest field peak of the para c singlet becomes
more defined. At 19 and 15 °C the high-field para c signal also
appears more defined. When the temperature is less than 15 °C,

2654 Organometallics, Vol. 29, No. 12, 2010
Mendoza et al.
Figure 13. COSY 19F-19F NMR spectrum of [Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4Cl-4)] (2b) at -20 °C (minor signals correspond to
c impurity).
to þ80 °C (relative intensities are 1:1:1:1:1 and 1:1:1:1 at all
temperatures).
Analysis of the meta absorptions in the 19F NMR spectra
from -80 to þ80 °C (Figure 15) was used to calculate the free
energies of activation for the rotation around the C-S bond
of both c and d C6F5 groups. The corresponding free energies
of activation for the compounds 2b-6b are in the range
58-59 ( 2 kJ mol-1 for groups c (S3-C or S4-C or S1-C7,
Figure 2) and in the range 62-63 ( 2 kJ mol-1 for groups d
3
(S4-C or S3-C or S1-C7, Figure 2). Although the NMR
absorptions are linked to the aromatic rings a, b, c, and d,
except for the rigid ring a, no definitive b, c, and d corre-
spondence can be established.
Summary Section
Previously, we found that the thermolysis reaction of
[Os(SC6F5)3(PMe2Ph)2] in refluxing toluene causes an oxi-
dative-rearrangement reaction affording [Os(SC6F5)2(S2-
C6F4)(PMe2Ph)] and [Os(C6F5)2(S2C6F4)(PMe2Ph)2]. This
reaction involves phosphane dissociation, cleavage of an
ortho C-F bond at a thiolate ligand, and transfer of a sulfur
atom along with oxidation of the metal center.32,33 However,
neither Os-F nor Os-aryl/alkyl(from phosphane) com-
plexes were yielded, and the fate of the exchanged fluorine
Figure 14. 19F NMR spectra of [Os(SC6F5)2(SC6F4(SC6F5)-2)-
(C6H4Cl-4)] (2b) at 80 °C, RT, and -20 °C. The letter labels
identify the signals that correspond to the same fluorinated ring,
including the relative integrals (minor signals correspond to c
impurity).
Indeed, rotation in the b C6F5 and a C6F4 groups is restricted
within the full range of temperatures measured from -80

Article
Organometallics, Vol. 29, No. 12, 2010 2655
Figure 15. Variable-temperature 19F NMR spectra of [Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4OCH3-4)] (6b) on the meta region of the
c and d groups (minor signals correspond to c impurity).
atom remained unknown. The related thermolysis reactions
of the compounds [Os(SC6F5)4(P(C6H4X-4)3)] reported here
show that the first products observed by TLC (compounds a)
contain a fluorine atom directly bonded to the metal center.
In fact, compounds a are isomers of the starting complexes,
likely arising from an intramolecular rearrangement result-
ing in displacement of an ortho fluorine from a -SC6F5
ligand by another -SC6F5 group with formation of the new
ligand {SC6F4(SC6F5)-2}-. All compounds a, b, and c con-
tain the {SC6F4(SC6F5)-2}- ligand. The thioether-sulfur of
this ligand is coordinated to the osmium center in com-
pounds b and c, but not in compounds a.
Scheme 4
Compounds b may originate from compounds a by an
exchange of P-C/F, with coordination of the Sthioether and
loss of coordination of the resulting fluorophosphane.
Compound d, obtained only through the thermolysis reac-
tion of 5, may originate from compound a by displacement of
the fluorine ligand by coordination of the Sthioether
.
A sequence of reactions for the formation of compounds a,
b, and d is suggested in Scheme 4.
Compounds c and e, which are obtained in similar low
yields, may originate through a ligand redistribution reac-
tion between two molecules a, as suggested in Scheme 5.
The thermolysis reaction of the isolated [OsF(SC6F5)2(SC6F4-
(SC6F5)-2)(P(C6H4CH3-4)3)] (5a) to give [Os(SC6F5)2(SC6F4(S-
C6F5)-2)(C6H4CH3-4)] (5b) and [Os(SC6F5)2(S2C6F4)(P(C6-
H4CH3-4)3)] (5d) also indicates that compounds a could be the
initial thermolysis products, and compounds b (as well as com-
pounds c and d) could then be formed from compounds a.
X-ray diffraction studies indicate that the monocoordi-
nated thiolate-thioether ligand in compounds 4a and 5a is
found in the hemisphere opposite the phosphane, in an
arrangement resembling the starting complex.46,42 This ar-
rangement suggests that the first step of the C-F bond
activation occurs in this hemisphere, without inversion at
the equatorial S thiolate atoms. Although in compounds 4a
and 5a the fluoride bound to the Os center survives TLC
analysis and preparative column separation on silica gel,
based on the X-ray studies and air-sensitivity in solution, this
fluoro ligand probably is not tightly bonded enough to the
metal center, which would facilitate an attack of the fluoro
ligand at the phosphane to induce P-C bond cleavage during
thermolysis (Scheme 4).
In a sealed NMR tube, [Os(SC6F5)4(P(C6H4Cl)3)] (2) in
C6D5CD3 was heated with an oil bath at 110 °C. The solution
was examined every two hours by 31P{1H} NMR at RT, but

2656 Organometallics, Vol. 29, No. 12, 2010
Mendoza et al.
Scheme 5
system yielding unusual compounds bearing Os-F bonds.
The starting thiolate ligands -SC6F5 are systematically trans-
formed into C6F5SC6F4S- and, when X=CH3, also into 1,2-
2-
S2C6F4
.
In each reaction, the heating in refluxing toluene causes
that the molecules of the starting compound to experience a
series of complex rearrangements to give always well-defined
products. Thus, formation of all products involves the
rupture of ortho C-F bonds from the original SC6F5 rings
in the starting material, cleavage of P-C, C-S, Os-S, and
Os-P bonds, and generation of new C-S, Os-C, and Os-F
bonds. This behavior is exhibited in all the compounds of the
series studied.
As shown by variable-temperature NMR studies, the new
molecules are fluxional and capable of adopting different
conformations of close configurational energies. It is prob-
able that this mobility contributes to the different intermedi-
ates required to render the output compounds found.
Experimental Section
Materials and Methods. All reactions were carried out under
argon using conventional Schlenk-tube techniques. TLC (Merck
5 ꢁ 7.5 cm2 Kiesegel 60 F254) was used to monitor the progress of
the reactions under study with hexane-CH2Cl2 (4:1) as eluent.
Complexes [Os(SC6F5)4(P(C6H4X-4)3)] werepreparedasrecently
published.42 The products were separated by passage through
a silica gel chromatographic column with a hexane-dichloro-
methane solution as eluent.
the spectra showed only the signals of the starting material42
and a doublet corresponding to the formation of [OsF-
(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4Cl)3)] (2a). There was
no evidence of the presence of PF(C6H4Cl)2 or P(C6H4Cl)3
(possible byproducts in the formation of 2b, 2e, and c,
Schemes 4 and 5). It is worth noting, however, that already
in the normal reactions the yields of 2b, 2e, and c are low and
that during the NMR experiment described above the cool-
ing-heating cycles probably affect the normal outcome of
this reaction. In addition, it has been documented that one
analogue of the expected products, PFPh2, disproportion-
ates to Ph2PF3 and Ph2PPPh2. In turn Ph2PF3, with traces of
water, gives rise to Ph2P(O)F and HF. The HF formed
attacks the unreacted Ph2PF to give Ph2PF2H.51 This variety
of probable phosphorus-containing byproducts in small
proportions means that 31P{1H} NMR signals are weak to
the point of being undetectable.
On the other hand, the C6F6 byproduct expected only in
the thermolysis reaction of 5 was detected by GC-MS in the
formation of the compound analogous to 5d, [Os(SC6F5)2-
(S2C6F4)(PMe2Ph)].32,33 In the present work, the yield of 5d
is again very low after a prolonged reaction time (see
Experimental Section) and combined with the huge number
of 19F NMR signals in the reaction mixture (complexes 5, 5a,
5b, and 5d), and their partial overlap precludes its unequi-
vocal identification.
Melting points were obtained on a Fisher-Johns melting point
apparatus.
IR spectra were recorded over the 4000-400 cm-1 range on a
Magna-Nicolet 750 FT-IR spectrometer using KBr pellets.
Data are expressed in wavenumbers (cm-1) with relative inten-
sities (vs=very strong, s=strong, m=medium, w=weak).
Positive ion FAB mass spectra were recorded on a Jeol JMS-
SX102A mass spectrometer operated at an accelerating voltage
of 10 kV. Samples were desorbed from a 3-nitrobenzyl alcohol
(NOBA) matrix using 3 keV xenon atoms. Mass measurements
in FAB are performed at a resolution of 3000 using magnetic
field scans and the matrix ions as the reference material.
Elemental analyses were determined by Galbraith Labora-
tories Inc.
19F, COSY 19F-19F, and 31P{1H} NMR spectra were re-
corded on a Varian Mercury VX400 spectrometer operating at
376, and 162 MHz respectively. Chemical shifts are relative to
CCl3F δ = 0 (19F) and H3PO4 δ = 0 (31P) using C6D5CD3 as
solvent.
All the free energies of activation, ΔG‡, reported in this paper
were calculated with the Eyring equation from variable-tem-
perature 19F NMR data, estimating the rate constant at the
coalescence temperature on the basis of the chemical shift
difference at lower temperatures.
Therefore, Schemes 4 and 5 show a likely sequence to
rationalize the results of these reactions, based on the
experimental evidence described above.
Reactions. The general method is described only for the case
of [Os(SC6F5)4(P(C6H4Cl-4)3)] (2): A 0.200 g (0.15 mmol)
sample of 2 was dissolved in toluene (20 mL). The stirred brown
solution was refluxed for 6 h. After this time, the solvent was
removed under vacuum, and the residue was purified by column
chromatography (silica gel, hexane-CH2Cl2, 1:2). Two frac-
tions were separated. The first fraction contains yet some of the
starting compound 2 and only very low quantities of 2b and c.
From the second fraction, by evaporation of the eluent under
vacuum at room temperature, is isolated a green powder that
contains a mixture of 2a and 2e (0.080 g), both compounds with
the same TLC retention factors. IR (KBr, cm-1): 1513(vs),
1494(vs), 1446(s), 1397(s), 1088(vs), 979(s), 821(w), 750(w).
FABþ-MS {m/z (%) [fragment]}:1333 (95) [Mþ2a - F], 1153 (90)
Conclusion
The apparently innocent thermal reactions of [Os-
(SC6F5)4(P(C6H4X-4)3)] (X=CF3 1, Cl 2, F 3, H 4, CH3 5,
and OCH3 6) are in fact the initial point of a very complex
(51) (a) Riesel, L.; Haenel, J. Z. Anorg. Allg. Chem. 1991, 603, 145–
150. (b) Riesel, L.; Haenel, J. J. Fluorine Chem. 1988, 38, 335–340.
(c) Brown, C.; Murray, M.; Schmutzler, R. J. Chem. Soc. C 1970, 878–
881. (d) Muetterties, E. L.; Mahler, W.; Schmutzler, R. Inorg. Chem. 1963, 2,
613–618. (e) Schmutzler, R. J. Chem. Soc. 1964, 4551–4557.
[Mþ2a - (SC6F5)], 973 (27) [Mþ - (SC6F4(SC6F5))], 770 (15)
2a

Article
Organometallics, Vol. 29, No. 12, 2010 2657
[Mþ2a - F - (SC6F5) - (P(C6H4Cl)3)], 603 (15) [Mþ - F -
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4CF3-4)3)] (1a). 19FNMR
(C6D5CD3, 80 °C), δ (ppm): -64.13 (s, 72F, 8(1P(C6H4CF3-4)3));
ring a, δ -124.38 (m, 8F, 8(1C6F4)), -128.60 (m, 8F, 8(1C6F4)),
-149.72 (m, 8F, 8(1C6F4)), -152.74 (m, 8F, 8(1C6F4)); ring b,
δ -133.15 (d, 16Fo, 8(1C6F5), 3JFo-Fm=24.8 Hz), -150.62 (t, 8Fp,
8(1C6F5), 3JFp-Fm=20.5 Hz), -160.40 (m, 16Fm, 8(1C6F5)); rings c,
δ -131.41 (br s, 32Fo, 8(2SC6F5)), -150.14 (br t, 16Fp, 8(2SC6F5),
3JFp-Fm = 20.3 Hz), -162.59 (br s, 32Fm, 8(2SC6F5)); F ligand,
δ -188.14 (d, 8(1Fax), 2JF-P=156 Hz).
2a
(SC6F5) - (P(C6H4Cl)3) - (C6F5)], 364 (100) [P(C6H4Cl)3]þ.
31P{1H} NMR (C6D5CD3, RT), δ (ppm): δ -4.80 (d, P(C6H4Cl-
4)3). 19F NMR spectra at 80 °C show the presence of 2a and 2e,
in a ratio of 7:1.
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4Cl-4)3)] (2a). 19F NMR
(C6D5CD3, 80 °C), δ (ppm): ring a, δ -124.66 (m, 7F, 7(1C6F4)),
-129.18 (m, 7F, 7(1C6F4)),-150.50 (m, 7F, 7(1C6F4)),-153.32 (m,
7F, 7(1C6F4)); ring b, δ -133.29 (d, 14Fo, 7(1C6F5), 3JFo-Fm=23.3
[OsF(SC6F5)3(P(C6H4CF3-4)3)] (1e). 19F NMR (C6D5CD3,
80 °C), δ (ppm): δ -64.08 (s, 9F, P(C6H4CF3-4)3), δ -131.82 (br s,
6Fo, 3SC6F5), -150.28 (t, 3Fp, 3SC6F5, 3JFp-Fm=19.6 Hz), -162.91
(m, 6Fm, 3SC6F5); F ligand, δ -184.90 (d, 1Fax, 2JF-P=156 Hz).
A brown product labeled as 1b (TLC analogous to the other
compounds of type b) was observed both by TLC and in the
chromatographic column, but it was not characterized because
of its very low yield. Traces of compound c were also observed in
3
Hz), -151.25 (t, 7Fp, 7(1C6F5), JFp-Fm =20.7 Hz), -160.64 (m,
14Fm, 7(1C6F5)); rings c, δ -131.56 (br s, 28Fo, 7(2SC6F5)),
-150.88 (br t, 14Fp, 7(2SC6F5), 3JFp-Fm=17.7 Hz), -163.02 (br s,
28Fm, 7(2SC6F5));Fligand, δ-190.21 (d, 7(1Fax), 2JF-P=158 Hz).
[OsF(SC6F5)3(P(C6H4Cl-4)3)] (2e). 19FNMR(C6D5CD3,80°C),
δ (ppm): -131.95 (br s, 6Fo, 3SC6F5), -151.05 (t, 3Fp, 3SC6F5,
3JFp-Fm=20.7 Hz), -163.35 (m, 6Fm, 3SC6F5); F ligand, δ -187.43
(d, 1Fax, 2JF-P=157 Hz).
To increase the yield of 2b, it was necessary to extend the time
of the reaction to 22 h, decreasing to traces the yield of 2a as a
consequence. The solvent was removed under vacuum, and the
residue was purified by column chromatography (silica gel,
hexane-CH2Cl2, 4:1). The first fraction contains the compound
2b and a second fraction contains the compounds c plus the
unreacted starting 2, additional passage through a new chroma-
tographic column being required to separate compounds c and 2.
this reaction and identified as [Os(SC6F5)3(SC6F4(SC6F5)-2)]25
by TLC comparison with an authentic sample.
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4F-4)3)] (3a): green
(0.044 g, 22%). Anal. Calcd for C42H12F23OsPS4: C, 38.72; H,
0.93; S, 9.84. Found: C, 38.53; H, 1.03; S, 9.86. Mp: 180 °C, dec.
IR (KBr, cm-1): 1514(vs), 1498(vs), 1447(s), 1398(w), 1243(s),
1089(vs), 980(s), 711(w). FABþ-MS {m/z (%) [fragment]}: 1284
(35) [Mþ - H - F], 1104 (24) [Mþ - H - (SC6F5)], 925 (9) [Mþ -
(SC6F4(SC6F5))], 770 (3) [Mþ - F - (SC6F5) - (P(C6H4F)3)],
603 (4) [Mþ - F - (SC6F5) - (P(C6H4F)3) - (C6F5)], 316
(100) [P(C6H4F)3]þ. 19F NMR (C6D5CD3, 80 °C), δ (ppm):
-106.67 (s, 3F, P(C6H4F-4)3); ring a, δ -124.78 (m, 1F, C6F4),
-129.29 (m, 1F, C6F4), -150.64 (m, 1F, C6F4), -153.45 (m, 1F,
C6F4); ring b, δ -133.35 (d, 2Fo, C6F5, 3JFo-Fm=21.8 Hz), -151.33
(t, 1Fp, C6F5, 3JFp-Fm=20.8 Hz), -160.73 (m, 2Fm, C6F5); rings c,
δ -131.63 (br s, 4Fo, 2SC6F5), -151.01 (br t, 2Fp, 2SC6F5),
-163.08 (br s, 4Fm, 2SC6F5); F ligand, δ -191.16 (d, 1Fax,
2JF-P=156 Hz). 31P{1H} NMR (C6D5CD3, RT), δ (ppm): -1.36
(d, 1P, P(C6H4F-4)3).
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4Cl-4)] (2b), was isolated
from the corresponding fraction as brown needle crystals (0.022 g,
14%) by slow evaporation of the eluent at room temperature.
Anal. Calcd for C30H4ClF19OsS4: C, 33.39; H, 0.37; S, 11.88.
Found: C, 33.44; H, <0.5; S, 12.06. Mp: 203 °C, dec. IR (KBr,
cm-1): 1515(vs), 1504(vs), 1485(vs), 1461(s), 1394(w), 1087(s),
979(s), 810(w). FABþ-MS {m/z (%) [fragment]}: 1080 (3) Mþ,
969 (10) [Mþ - (C6H4Cl)], 881(6) [Mþ - (SC6F5)], 770(41) [Mþ -
(SC6F5) - (C6H4Cl)], 603 (10) [Mþ - (SC6F5) - (C6H4Cl) -
(C6F5)], 436 (4) [Mþ - (SC6F5) - (C6H4Cl) - 2(C6F5)]. 19F
NMR (C6D5CD3, RT), δ (ppm): ring a, δ -130.94 (ddd, 1F,
C6F4, 3JF-F=22.6 Hz, 4JF-F=10.9 Hz, 5JF-F=4.1), -133.13 (m,
1F, C6F4), -145.05 (td, 1F, C6F4, 3JF-F =21.4 Hz, 4JF-F =6.8
Hz), -152.9 (m, 1F, C6F4); ring b, δ -130.04 (m, 1Fo, C6F5),
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4F-4)] (3b): brown plate
crystals (0.018 g, 11%). Anal. Calcd for C30H4F20OsS4: C,
33.90; H, 0.36; S, 12.07. Found: C, 33.93; H, 0.58; S, 12.50.
Mp: 215 °C, dec. IR (KBr, cm-1): 1515(vs), 1506(vs), 1486(vs),
1462(s), 1394(w), 1232(s), 1087(s), 979(s). FABþ-MS {m/z (%)
[fragment]}: 1064 (1) Mþ, 865 (5) [Mþ - (SC6F5)], 770 (22)
[Mþ - (SC6F5) - (C6H4F)], 666 (5) [Mþ - 2(SC6F5)], 603 (8)
[Mþ - (SC6F5) - (C6H4F) - (C6F5)], 571 (3) [Mþ - 2(SC6F5) -
(C6H4F)], 436 (3) [Mþ - (SC6F5) - (C6H4F) - 2(C6F5)], 404 (1)
[Mþ - 2(SC6F5) - (C6H4F) - (C6F5)]. 19F NMR (C6D5CD3,
RT), δ (ppm): ring a, δ -129.88 (ddd, 1F, C6F4, 3JF-F=22.7 Hz,
4JF-F=11.7 Hz, 5JF-F=4.1 Hz), -132.01 (m, 1F, C6F4), -143.84
(td, 1F, C6F4, 3JF-F=22.0 Hz, 4JF-F=6.8 Hz), -151.63 (m, 1F,
C6F4); ring b, δ -128.94 (m, 1Fo, C6F5), -134.84 (d, 1Fo0, C6F5,
3
-136.00 (d, 1Fo0, C6F54, JFo-Fm = 19.2 Hz), -144.19 (tt, 1Fp,
3
C6F5, JFp-Fm = 22.2, JFp-Fo = 5.6 Hz), -157.65 (td, 1Fm0,
C6F5, 3JFm-Fo/p=21.8 Hz), -158.60 (td, 1Fm, C6F5, 3JFm-Fo/p
=
22.2 Hz, 4JFm-Fm=6.8 Hz); ring c, δ -132.35 (br s, 1Fo, 1SC6F5),
-133.71 (br s, 1Fo0, 1SC6F5), -150.71 (t, 1Fp, 1SC6F5,
3JFp-Fm = 20.3 Hz), -160.71 (br s, 1Fm, 1SC6F5), -161.69 (br s,
1Fm0, 1SC6F5); ring d, δ -131.10 (d, 1Fo, 1SC6F5, 3JFo-Fm=23.3
Hz), -131.94 (d, 1Fo0, 1SC6F5, 3JFo-Fm=20.7 Hz), -151.71 (t, 1Fp,
1SC6F5, 3JFp-Fm=20.7 Hz), -162.62 (t, 1Fm, 1SC6F5, 3JFm-Fo/p
20.7 Hz), -162.9 (t, 1Fm0, 1SC6F5, 3JFo-Fm=19.2 Hz).
=
Compound c was isolated in a very low yield, due to poor
separation with respect to the starting complex 2 in the chro-
matographic column, and was identified as the green complex
3
3JFo-Fm = 19.2), -143.02 (t, 1Fp, C6F5, JFp-Fm = 21.8 Hz),
3
4
-156.30 (td, 1Fm0, C6F5, JFm-Fo/p = 22.0 Hz, JFm-Fm = 6.8
Hz),-157.26 (td, 1Fm, C6F5, 3JFm-Fo/p=22.0 Hz, 4JFm-Fm=6.8
Hz); ring c, δ -131.25 (br s, 1Fo, 1SC6F5), -132.58 (br s, 1Fo0,
1SC6F5), -149.48 (t, 1Fp, 1SC6F5, 3JFp-Fm=20.7 Hz), -159.38
(br s, 1Fm, 1SC6F5), -160.31 (br s, 1Fm0, 1SC6F5); ring d, δ
-130.00 (m, 1Fo, 1SC6F5), -130.81 (m, 1Fo0, 1SC6F5), -150.66
(t, 1Fp, 1SC6F5, 3JFp-Fm=20.7 Hz), -161.40 (m, 1Fm, 1SC6F5),
-161.64 (m, 1Fm0, 1SC6F5).
previously reported as [Os(SC6F5)3(SC6F4(SC6F5)-2)]25 by FAB
mass spectrometry.
Analogous reactions from 1 and 3-6 (0.200 g) afforded the
next compounds (yields are from the corresponding isolated
complexes):
Mixture of 1a and 1e: green powder (0.100 g), both com-
pounds with the same TLC retention factors. IR (KBr, cm-1):
1515(vs), 1497(vs), 1399(m), 1323(s), 1176(s), 1137(s), 1091(vs),
982(s), 706(w). FABþ-MS {m/z (%) [fragment]}: 1435 (57)
Compound [Os(SC6F5)3(SC6F4(SC6F5)-2)]25 (c) was isolated
as green crystals (0.007 g, 4%).
[Mþ - F], 1255 (59) [Mþ - (SC6F5)], 1075 (19) [Mþ
-
1a
1a
1a
(SC6F4(SC6F5))], 770 (15) [Mþ - F - (SC6F5) - (P(C6H4-
1a
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H5)3)] (4a): green crys-
tals (0.066 g, 33%). Anal. Calcd for C42H15F20OsPS4: C,
40.39; H, 1.21; S, 10.27. Found: C, 40.34; H, 1.40; S, 10.12.
Mp: 184 °C, dec. IR (KBr, cm-1): 1512(vs), 1494(vs), 1445(w),
1398(s), 1088(s), 979(s), 746(w), 693(w). FABþ-MS {m/z (%)
[fragment]}: 1231 (49) [Mþ - F], 1051 (37) [Mþ - (SC6F5)], 1032
CF3)3)], 603 (18) [Mþ - F - (SC6F5) - (P(C6H4CF3)3) -
1a
(C6F5)], 571 (15) [Mþ1a - F - 2(SC6F5) - (P(C6H4CF3)3)], 466
(100) [P(C6H4CF3)3]þ. 31P{1H} NMR (C6D5CD3, RT), δ (ppm):
-1.33 (d, P(C6H4CF3-4)3). 19F NMR spectra at 80 °C show the pre-
sence of 1a and 1e, in a ratio of 8:1.

2658 Organometallics, Vol. 29, No. 12, 2010
Mendoza et al.
(4) [Mþ - F - (SC6F5)], 871 (9) [Mþ - (SC6F4(SC6F5))], 770 (2)
[Mþ - F - (SC6F5) - (P(C6H5)3)], 603 (3) [Mþ - F - (SC6F5) -
(P(C6H5)3) - (C6F5)], 262 (100) [P(C6H5)3]þ. 19F NMR
(C6D5CD3, 80 °C), δ (ppm): ring a, δ -124.70 (m, 1F, C6F4),
-129.87 (m, 1F, C6F4), -151.45 (m, 1F, C6F4), -153.93 (m, 1F,
4JFm-Fm=7.2 Hz); ring c, δ -131.34 (br s, 1Fo, 1SC6F5), -132.76
(br s, 1Fo0, 1SC6F5), -150.11 (t, 1Fp, 1SC6F5, 3JFp-Fm=20.7 Hz),
-159.65 (br s, 1Fm, 1SC6F5), -160.70 (br s, 1Fm0, 1SC6F5); ring d,
δ -129.88 (d, 1Fo, 1SC6F5, 3JFo-Fm=24.8 Hz), -130.84 (d, 1Fo0,
3
1SC6F5, JFo-Fm = 26.0 Hz), -152.25 (m, 1Fp, 1SC6F5, full
3
integral =2), -162.13 (m, 1Fm, 1SC6F5), -162.35 (m, 1Fm0,
1SC6F5).
C6F4); ring b, δ -133.34 (d, 2Fo, C6F5, JFo-Fm = 21.8 Hz),
3
-152.11 (t, 1Fp, C6F5, JFp-Fm = 20.7 Hz), -161.07 (m, 2Fm,
C6F5); rings c, δ -131.52 (br s, 4Fo, 2SC6F5), -151.89 (br t, 2Fp,
[Os(SC6F5)2(S2C6F4)(P(C6H4CH3-4)3)] (5d): green crystals
(0.0034 g, 2%). Anal. Calcd for C39H21F14OsPS4: C, 42.39; H,
1.92; S, 11.61. Found: C, 42.22; H, 1.85; S, 11.75. Mp: 220 °C,
dec. IR (KBr, cm-1): 1512(vs), 1494(vs), 1441(s), 1394(w),
1087(s), 979(s), 845(w). FABþ-MS {m/z (%) [fragment]}: 1106
(38) Mþ, 1087 (3) [Mþ - F], 1015 (2) [Mþ - (C6H4CH3)], 939 (3)
3
2SC6F5, JFp-Fm = 19.6 Hz), -163.53 (br s, 4Fm, 2SC6F5);
F ligand, δ -192.59 (d, 1Fax, 2JF-P =154 Hz). 31P{1H} NMR
(C6D5CD3, RT), δ (ppm): 0.22 (d, 1P, P(C6H5)3).
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H5)] (4b): brown crystals
(0.0085 g, 5%). Anal. Calcd for C30H5F19OsS4: C, 34.49; H,
0.48; S, 12.27. Found: C, 34.34; H, 0.60; S, 12.79. Mp: 220 °C,
dec. IR (KBr, cm-1): 1514(vs), 1506(vs), 1485(vs), 1460(s), 1392-
(w), 1087(s), 978(s), 737(w). FABþ-MS {m/z (%) [fragment]}:
1046 (1) Mþ, 969 (3) [Mþ - (C6H5)], 847 (3) [Mþ - (SC6F5)],
770 (8) [Mþ - (SC6F5) - (C6H5)], 603 (2) [Mþ - (SC6F5) -
(C6H5) - (C6F5)]. 19F NMR (C6D5CD3, RT), δ (ppm): ring a,
[Mþ - (C6F5)], 907 (12) [Mþ - (SC6F5)], 739 (10) [Mþ
-
(SC6F5) - H - (C6F5)], 727 (2) [Mþ - (C6F5) - (S2C6F4)],
615 (3) [Mþ - 2(SC6F5) - (C6H4CH3) - 2H].
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4OCH3-4)3)] (6a): green
powder (0.046 g, 23%). Anal. Calcd for C45H21F20O3OsPS4: C,
40.36; H, 1.58; S, 9.58. Found: C, 40.42; H, 1.72; S, 9.51. Mp: 175 °C,
dec. IR (KBr, cm-1): 1514(vs), 1498(vs), 1445(s), 1398(w), 1258(s),
1088(s), 980(s), 801(w). FABþ-MS {m/z (%) [fragment]}: 1321 (18)
[Mþ - F], 1154 (1) [Mþ - F - (C6F5)], 1141 (14) [Mþ - (SC6F5)],
1122 (4) [Mþ - F - (SC6F5)], 961 (3) [Mþ - (SC6F4(SC6F5))],
δ -130.01 (ddd, 1F, C6F4, 3JF-F=22.4 Hz, 4JF-F=11.5 Hz, 5JF-F
=
2.2 Hz), -132.28 (m, 1F, C6F4), -144.27 (td, 1F, C6F4, 3JF-F=20.7
Hz, 4JF-F=5.6 Hz), -152.11 (m, 1F, C6F4); ring b, δ -129.01 (m,
1Fo, C6F5), -135.00 (d, 1Fo0, C6F5, 3JFo-Fm=21.8 Hz), -143.48 (t,
770 (1) [Mþ - F - (SC6F5) - (P(C6H4OCH3)3)], 603 (2) [Mþ
-
1Fp, C6F5, 3JFp-Fm=20.7 Hz), -156.61 (td, 1Fm0, C6F5, 3JFm-Fo/p
=
F - (SC6F5) - (P(C6H4OCH3)3) - (C6F5)], 352 (100) [P(C6H4-
OCH3)3]þ. 19FNMR(C6D5CD3,80°C), δ(ppm):ringa, δ-124.76
(m, 1F, C6F4), -129.72 (m, 1F, C6F4), -151.61 (m, 1F, C6F4),
22.0 Hz, 4JFm-Fm=6.8 Hz), -157.52 (td, 1Fm, C6F5, 3JFm-Fo/p=22.0
4
Hz, JFm-Fm = 5.6 Hz); ring c, δ -131.36 (br s, 1Fo, 1SC6F5),
=
-132.73 (br s, 1Fo0, 1SC6F5), -149.99 (t, 1Fp, 1SC6F5, 3JFp-Fm
-153.93 (m, 1F, C6F4); ring b, δ -133.22 (d, 2Fo, C6F5, 3JFo-Fm
=
20.7 Hz), -159.61 (br s, 1Fm, 1SC6F5), -160.56 (br s, 1Fm0,
21.8 Hz), -152.23 (t, 1Fp, C6F5, 3JFp-Fm=20.7 Hz), -161.05 (m,
2Fm, C6F5); rings c, δ -131.45 (br s, 4Fo, 2SC6F5), -152.02 (br t,
2Fp, 2SC6F5, 3JFp-Fm=18.1 Hz), -163.50 (br s, 4Fm, 2SC6F5); F
3
1SC6F5); ring d, δ -130.21 (d, 1Fo, 1SC6F5, JFo-Fm =23.3 Hz),
3
-131.01 (d, 1Fo0, 1SC6F5, JFo-Fm = 24.4 Hz), -151.54 (t, 1Fp,
1SC6F5, 3JFp-Fm=20.7 Hz), -161.95 (m, 1Fm, 1SC6F5), -162.23
(m, 1Fm0, 1SC6F5).
2
ligand, δ -193.62 (d, 1Fax, JF-P = 156 Hz). 31P{1H} NMR
(C6D5CD3, RT), δ (ppm): -5.10 (d, 1P, P(C6H4OCH3-4)3).
[Os(SC6F5)3(SC6F4(SC6F5)-2)]25 (c) was isolated as green
crystals (0.006 g, 3%).
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4OCH3-4)] (6b): green
crystals (0.015 g, 9%). Anal. Calcd for C31H7F19OOsS4: C,
34.64; H, 0.66; S, 11.93. Found: C, 34.72; H, 0.80; S, 11.82. Mp:
180 °C, dec. IR (KBr, cm-1): 1513(vs), 1499(vs), 1463(s),
1393(w), 1086(s), 980(s), 847(w). FABþ-MS {m/z (%)
[fragment]}: 1076 (17) [M]þ, 969 (42) [Mþ - (C6H4OCH3)],
877 (38) [Mþ - (SC6F5)], 770 (56) [Mþ - (SC6F5) -
[OsF(SC6F5)2(SC6F4(SC6F5)-2)(P(C6H4CH3-4)3)] (5a): green
crystals (0.080 g, 40%). Anal. Calcd for C45H21F20OsPS4: C,
41.86; H, 1.64; S, 9.93. Found: C, 42.05; H, 1.83; S, 9.75. Mp:
150 °C, dec. IR (KBr, cm-1): 1512(vs), 1494(vs), 1445(s), 1398(w),
1088(s), 978(vs), 806(w). FABþ-MS {m/z (%) [fragment]}: 1273
(29) [Mþ - F], 1093 (24) [Mþ - (SC6F5)], 913 (7) [Mþ - (SC6F4-
(SC6F5))], 304 (100) [P(C6H4CH3)3]þ. 19F NMR (C6D5CD3,
80 °C), δ (ppm): ring a, δ -124.81 (m, 1F, C6F4), -129.86 (m,
1F, C6F4), -151.66 (m, 1F, C6F4), -154.05 (m, 1F, C6F4); ring b, δ
-133.32 (d, 2Fo, C6F5, 3JFo-Fm=23.3 Hz), -152.33 (t, 1Fp, C6F5,
3JFp-Fm = 20.7 Hz), -161.18 (m, 2Fm, C6F5); rings c, δ -131.58
(br s, 4Fo, 2SC6F5), -152.09 (br m, 2Fp, 2SC6F5), -163.64
(C6H4OCH3)], 678 (21) [Mþ - 2(SC6F5)], 603 (20) [Mþ
-
(SC6F5) - (C6H4OCH3) - (C6F5)], 436 (6) [Mþ - (SC6F5) -
(C6H4OCH3) - 2(C6F5)]. 19F NMR (C6D5CD3, RT), δ (ppm):
ring a, δ -130.16 (ddd, 1F, C6F4, 3JF-F=24.8 Hz, 4JF-F=11.5
5
Hz, JF-F = 4.1 Hz), -132.31 (m, 1F, C6F4), -144.42 (td, 1F,
C6F4, 3JF-F=21.2 Hz, 4JF-F=6.8 Hz), -152.26 (m, 1F, C6F4);
ring b, δ -129.17 (m, 1Fo, C6F5), -135.08 (d, 1Fo, C6F5,
3JFo-Fm =23.3 Hz), -143.67 (tt, 1Fp, C6F5, 3JFp-Fm=20.7 Hz,
4JFp-Fo=4.1 Hz), -156.69 (td, 1Fm0, C6F5, 3JFm-Fo/p=22.8 Hz,
4JFm-Fm=8.3 Hz),-157.57 (td, 1Fm, C6F5, 3JFm-Fo/p=22.2 Hz,
4JFm-Fm = 6.8 Hz); ring c, δ -131.47 (br s, 1Fo, 1SC6F5),
-132.71 (br s, 1Fo0, 1SC6F5), -150.13 (t, 1Fp, 1SC6F5,
3JFp-Fm =20.7 Hz), -159.70 (br s, 1Fm, 1SC6F5), -160.66 (br
2
(br s, 4Fm, 2SC6F5); F ligand, δ -193.16 (d, 1Fax, JF-P = 148
Hz). 31P{1H} NMR (C6D5CD3, RT), δ (ppm): -7.54 (d, 1P,
P(C6H4CH3-4)3).
[Os(SC6F5)2(SC6F4(SC6F5)-2)(C6H4CH3-4)] (5b): green crys-
tals (0.020 g, 12%). Anal. Calcd for C31H7F19OsS4: C, 35.17; H,
0.67; S, 12.11. Found: C, 34.97; H, 0.85; S, 12.23. Mp: 184 °C,
dec. IR(KBr,cm-1):1515(vs), 1497(vs), 1462(s), 1394(w), 1087(s),
979(s), 801(w). FABþ-MS {m/z (%) [fragment]}: 1059 (9) [M -
H]þ, 969 (36) [Mþ - (C6H4CH3)], 861 (44) [Mþ - (SC6F5)], 770
(80) [Mþ - (SC6F5) - (C6H4CH3)], 694 (7) [Mþ - (SC6F5) -
(C6F5)], 662 (27) [Mþ - 2(SC6F5)], 603 (26) [Mþ - (SC6F5) -
(C6H4CH3) - (C6F5)], 436 (10) [Mþ - (SC6F5) - (C6H4CH3) -
2(C6F5)], 436 (10) [Mþ - (SC6F5) - (C6H4CH3) - 2(C6F5)], 404
(6) [Mþ - 2(SC6F5) - (C6H4CH3) - (C6F5)]. 19F NMR
(C6D5CD3, RT), δ (ppm): ring a, δ -130.05 (ddd, 1F, C6F4,
s, 1Fm0, 1SC6F5)); ring d, δ -129.83 (d, 1Fo, 1SC6F5, 3JFo-Fm
=
24.8 Hz), -130.75 (d, 1Fo, 1SC6F5, 3JFo-Fm=23.3 Hz), -152.04
(t, 1Fp, 1SC6F5, 3JFp-Fm=20.7 Hz), -162.14 (m, 1Fm, 1SC6F5),
-162.37 (m, 1Fm0, 1SC6F5).
[Os(SC6F5)3(SC6F4(SC6F5)-2)]25 (c) was isolated as green
crystals (0.005 g, 3%).
Crystallography. Air-stable single crystals of complexes
2b-6b and 5d were obtained by slow evaporation of their air-
stable solutions (hexane-CH2Cl2, 4:1). However, crystals of 4a
and 5a were obtained from their solutions (hexane-CH2Cl2,
1:9) under argon atmospheres, because of their air sensitivity in
solution. A green mixture of 2a and 2e was dissolved in
hexane-CH2Cl2 (1:9) and kept under Ar atmosphere. After a
few hours the solution turned purple with decomposition of 2a,
and over time, a dark green crystal of 2e deposited.
4
5
3JF-F = 22.3 Hz, JF-F = 10.9 Hz, JF-F = 2.6 Hz), -132.31 (m,
1F, C6F4), -144.39 (td, 1F, C6F4, 3JF-F=21.2 Hz, 4JF-F=6.8 Hz),
-152.25 (m, 1F, C6F4, full integral =2); ring b, δ -129.05 (m, 1Fo,
C6F5), -135.04 (d, 1Fo0, C6F5, 3JFo-Fm=20.7 Hz), -143.56 (t, 1Fp,
C6F5, 3JFp-Fm=22.2 Hz), -156.65 (td, 1Fm0, C6F5, 3JFm-Fo/p=22.6
Hz, 4JFm-Fm=6.8 Hz),-157.56 (td, 1Fm, C6F5, 3JFm-Fo/p=22.0 Hz,

Article
Organometallics, Vol. 29, No. 12, 2010 2659
Table 1. X-ray Parameters
5a
4a
2b
3b
chem formula
fw
space group
a/A
b/A
c/A
C
42H15F20OsPS4
C45H21F20OsPS4 0.5(H2O)
3
C30H4ClF19OsS4
1079.22
P1
C30H4F20OsS4
1062.77
P1
1248.95
P1
1300.04
P1
11.4570(11)
12.0914(11)
18.4994(16)
84.886(5)
73.213(6)
64.074(6)
2204.6(3)
2
11.6506(13)
12.6198(14)
18.777(2)
77.420(8)
72.116(8)
67.338(9)
2408.9(5)
2
10.7595(18)
12.3939(12)
13.8046(16)
72.201(6)
79.379(11)
82.299(10)
1716.8(4)
2
10.7540(12)
12.3279(11)
13.1539(13)
73.671(7)
80.942(9)
83.05(1)
1647.2(3)
2
R/deg
β/deg
γ/deg
V/A3
Z
μ/mm-1
3.235
2.965
4.163
4.262
R indices [I > 2σ(I)]a
R indices (all data) a
Dcalc/g cm-3
data/params
Sa
0.039, 0.062
0.064, 0.068
1.881
6088/613
1.047
0.043, 0.092
0.061, 0.099
1.792
8365/658
1.015
0.034, 0.083
0.043, 0.090
2.088
7745/496
1.017
0.070, 0.197
0.081, 0.205
2.143
5690/496
1.120
4b
5b
6b
5d
2e
chem formula
fw
space group
a/A
b/A
c/A
C30H5F19OsS4
1044.78
P1
C31H7F19OsS4
1058.81
P1
C31H7F19OOsS4
1074.81
P1
C39H21F14OsPS4
1104.97
P1
C36H12Cl3F16OsPS3 1.38(CH2Cl2)
3
1289.35
R3
10.7829(13)
12.2538(13)
12.7859(15)
74.697(7)
82.010(10)
83.771(9)
1609.1(3)
2
10.5552(10)
12.3092(13)
13.6336(11)
87.486(8)
76.577(4)
82.634(10)
1708.6(3)
2
11.2820(7)
12.5292(8)
12.6534(7)
80.587(5)
78.904(4)
75.411(6)
1686.07(18)
2
10.648(2)
14.992(2)
15.431(3)
69.348(10)
85.700(13)
74.435(12)
2219.8(7)
2
15.3769 (13)
15.3769 (13)
34.068 (4)
90
90
120
6976.2 (11)
6
3.335
0.052, 0.112
0.092, 0.124
1.841
R/deg
β/deg
γ/deg
V/A3
Z
μ/mm-1
4.357
4.105
4.164
3.182
R indices [I > 2σ(I)]a
R indices (all data) a
Dcalc/g cm-3
data/params
0.026, 0.061
0.032, 0.063
2.156
0.034, 0.081
0.043, 0.086
2.058
0.030, 0.067
0.038, 0.070
2.117
0.047, 0.102
0.076, 0.114
1.653
5978/535
1.013
9286/488
1.040
8867/497
1.062
8897/506
1.053
2727/181
1.011
Sa
P
P
P
P
P
a R1 = [ ||Fo| - |Fc||]/[ |Fo|], wR2 = [ w(Fo2 - Fc2)2/ w(Fo2)2]1/2, S = [ w(Fo2 - Fc2)2/(data - params)]1/2
.
Pertinent crystal data and other crystallographic parameters
are listed in Table 1. Diffraction data were collected at room
temperature (294-298 K) using a Bruker P4 diffractometer
equipped with Mo KR radiation (λ=0.71073 A), using the stan-
dard procedure,52 and raw data were corrected for absorption
effects using suitable Ψ-scan data.53 In all cases, the Os site may
be found by interpreting a Patterson map, and the structure of
the complex was completed by analyzing difference maps. Final
refinements were carried out54 without restraints nor constraints
for non-H atoms. H atoms were placed in idealized positions
and refined as riding on their carrier C atoms. In the case of 5a,
the crystal was found to be a hemihydrate, and the water
molecule geometry was regularized through soft restraints,
molecules are packed in the crystal in such a way that large void
spaces are present, representing 18.8% of the unit cell volume.
Since the shape of the voids does not match the geometry of
n-hexane, they were assumed to be filled by disordered CH2Cl2
molecules. The contribution of the disordered solvent to the
structure factors was estimated using the SQUEEZE procedure
implemented in PLATON.55 A total of 347 electrons per unit
cell were recovered, interpreted as 8.26 solvent molecules per
unit cell, i.e., 1.38 solvent molecules per osmium complex
(Z=6). In the thiolate benzene ring, the C10-C11 bond length
was restrained to 1.37(1) A; otherwise this bond length con-
verged to a too small distance of ca. 1.30 A. Complete geometric
parameters may be consulted from the archived CIF file, and
diffraction data are available on request from the authors.
O-H = 0.85(1) A and H H = 1.34(2) A. The somewhat
3 3 3
disappointing refinements for 3b and 5d (R1 = 7% and 5%,
respectively) are a consequence of the crystal habits: these
complexes crystallize as very thin plates with a thickness of ca.
40 μm, which makes the correction for absorption difficult to
apply. For both complexes 4a and 5d, data resolution was also
limited to 0.91 A (2θmax = 46° for Mo KR radiation) since
crystals are poorly diffracting samples. In the case of 2e,
Acknowledgment. We gratefully acknowledge CONA-
CYT (27915E), VIEP (ARCS-NAT-09-G), and PRO-
MEP for financial support. S.B. acknowledges BUAP
for the use of diffraction facilities.
Supporting Information Available: X-ray crystallographic
files, in CIF format, for the structures of compounds 4a, 5a,
2b-6b, 5d, and 2e are available free of charge via the Internet at
http://pubs.acs.org.
(52) XSCAnS (release 2.21) Users Manual; Siemens Analytical X-ray
Instruments Inc.: Madison, WI, 1996.
(53) North, A. C. T.; Phillips, D. C.; Mathews, F. S. Acta Crystallogr.
1968, A24, 351–359.
(54) Sheldrick, G. M. Acta Crystallogr. 2008, A64, 112–122.
(55) Spek, A. L. J. Appl. Crystallogr. 2003, 36, 7–13.