Comparative reactivity studies of dppf-containing CpRuII and (C6Me6)RuII complexes towards different donor ligands (dppf=1,1′-bis(diphenylphosphino)ferrocene)

Article abstract of DOI:10.1016/j.jorganchem.2004.03.022

[CpRu(dppf)Cl] (Cp=η⁵-C₅H₅) (1) and [(HMB)Ru(dppf)Cl]PF₆ ((HMB)=η⁶-C₆Me₆) (3) react with different donor ligands to give rise to N-, P- and S-bonded complexes. The stoichiometric reactions of 1 and 3 with NaNCS give the mononuclear complexes [CpRu(dppf)(NCS)] (2) and [(HMB)Ru(dppf)(NCS)]PF₆ (4), respectively, in yields above 80%, while 3 also gives a dppf-bridged diruthenium complex [(HMB)Ru(NCS)₂]₂ (μ-dppf) (5) in 67% yield from reaction with four molar equivalents of NaNCS. Compound 5 is also obtained in 70% yield from the reaction of 4 with excess NaNCS. With CH₃CN in the presence of salts, both 1 and 3 give their analogous solvento derivatives [CpRu(dppf) (CH₃CN)] BPh₄ (6) and [(HMB)Ru(dppf) (CH₃CN)] (PF₆)₂ (7). With phosphines, the reaction of 1 gives chloro-displaced complexes [(CpRu(dppf)L]PF₆ (L =PMe₃ (8), PMe₂Ph(9), whereas the reaction of 3 with PMe₂Ph leads to substitution of dppf, giving [(HMB)Ru(PMe₂Ph)₂Cl] PF₆ (10). The reaction of 1 with NaS₂CNEt₂ gives a dinuclear dppf-bridged complex [{CpRu(S₂CNEt₂)} ₂(μ-dppf)] (11), whereas that of 3 results in loss of the HMB ligand giving a mononuclear complex [Ru(dppf) (S₂CNEt₂)₂] (12). With elemental sulfur S₈, 1 is oxidized to give a dinuclear CpRu^III dppf-chelated complex [{CpRu(dppf)}₂(μ-S₂)] (BPh₄)Cl (13), whereas 3 undergoes oxidation at the ligand, giving a dppf-displaced complex [(HMB)Ru(CH₃CN)₂Cl] PF₆ (14) and free dppfS₂. The structures of 1, 2, 5-9, 11, 13 and 14 were established by X-ray single crystal diffraction analyses. Of these, 5 and 11 both contain a dppf-bridge between Ru^II centers, while 13 is a dinuclear CpRu^III disulfide-bridged complex; all the others are mononuclear. All complexes obtained were also spectroscopically characterized.

Full text of DOI:10.1016/j.jorganchem.2004.03.022

Journal of Organometallic Chemistry 689 (2004) 1978–1990
www.elsevier.com/locate/jorganchem
Comparative reactivity studies of dppf-containing CpRuII and
(C6Me6)RuII complexes towards different donor ligands
(dppf ¼ 1,10-bis(diphenylphosphino)ferrocene)
Xiu Lian Lu, Jagadese J. Vittal, Edward R.T. Tiekink, G.K. Tan, Seah Ling Kuan,
*
*
Lai Yoong Goh , T.S. Andy Hor
Department of Chemistry, National University of Singapore, Kent Ridge, Singapore 117543, Singapore
Received 27 January 2004; accepted 18 March 2004
Abstract
[CpRu(dppf)Cl] (Cp ¼ g5-C5H5) (1) and [(HMB)Ru(dppf)Cl]PF6 ((HMB) ¼ g6-C6Me6) (3) react with different donor ligands to
give rise to N-, P- and S-bonded complexes. The stoichiometric reactions of 1 and 3 with NaNCS give the mononuclear complexes
[CpRu(dppf)(NCS)] (2) and [(HMB)Ru(dppf)(NCS)]PF6 (4), respectively, in yields above 80%, while 3 also gives a dppf-bridged
diruthenium complex [(HMB)Ru(NCS)2]2(l-dppf) (5) in 67% yield from reaction with four molar equivalents of NaNCS. Com-
pound 5 is also obtained in 70% yield from the reaction of 4 with excess NaNCS. With CH3CN in the presence of salts, both 1 and 3
give their analogous solvento derivatives [CpRu(dppf)(CH3CN)]BPh4 (6) and [(HMB)Ru(dppf)(CH3CN)] (PF6)2 (7). With phos-
phines, the reaction of 1 gives chloro-displaced complexes [(CpRu(dppf)L]PF6 (L ¼ PMe3 (8), PMe2Ph(9)), whereas the reaction of
3 with PMe2Ph leads to substitution of dppf, giving [(HMB)Ru(PMe2Ph)2Cl] PF6 (10). The reaction of 1 with NaS2CNEt2 gives a
dinuclear dppf-bridged complex [{CpRu(S2CNEt2)}2(l-dppf)] (11), whereas that of 3 results in loss of the HMB ligand giving a
mononuclear complex [Ru(dppf)(S2CNEt2)2] (12). With elemental sulfur S8, 1 is oxidized to give a dinuclear CpRuIII dppf-chelated
complex [{CpRu(dppf)}2(l-S2)](BPh4)Cl (13), whereas 3 undergoes oxidation at the ligand, giving a dppf-displaced complex
[(HMB)Ru(CH3CN)2Cl]PF6 (14) and free dppfS2. The structures of 1, 2, 5–9, 11, 13 and 14 were established by X-ray single crystal
diffraction analyses. Of these, 5 and 11 both contain a dppf-bridge between RuII centers, while 13 is a dinuclear CpRuIII disulfide-
bridged complex; all the others are mononuclear. All complexes obtained were also spectroscopically characterized.
Ó 2004 Elsevier B.V. All rights reserved.
Keywords: Ruthenium; 1,10-bis(diphenylphosphino)ferrocene; Cyclopentadienyl; Hexamethylbenzene; Disulfide; Crystal structures
1. Introduction
phosphine ligand. This ligand has attracted our recent
interest because of its coordination variability and the
catalytic potential it can confer on a complex [6,7]. d6-
RuII complexes containing dppf are known [7] with
about 20 crystallographic reports. These include three-
legged piano-stool structures [(C5R5)Ru(dppf)H] (R ¼
Me [8]; R ¼ H [9]), [(g6-arene)Ru(dppf)Cl]PF6 (arene ¼
HMB [10], p-cymene [11]), [(g6-Me4-C6H2)RuCl2]2(l-
dppf) ꢀ CH2Cl2 [10], [CpRu(dppf)(CBC-(C5H4NH))-
W(CO)4(PPh3)] [12], [TpRu(dppf)Cl] and [Tp(dppf)
Ru@C@C@CPh2]SbF6 [13] (Tp ¼ tris(pyrazolyl)borate),
a four-legged piano-stool complex [Cp*Ru(dppf)(g2-
O2)]BF4 [14], and other octahedral structures [Ru-
(dppf)(bipy)2](PF6)2 [15], [Ru(dppf)(CO)(PPh3)(Cl)H]
[16], [Ru(dppf)(CO)(NCMe)(PPh3)H]BF4 ꢀ EtOH [17],
The organometallic chemistry of [CpRu(PR3)2Cl]
[1,2] has been extensively studied and the related g6-
arene complexes are also known [3]. However, little is
reported of their comparative reactivities. The electronic
and steric differences of these aromatic p-ligands could
confer on a metal complex different chemical and cata-
lytic reactivity features [4,5]. Such differences could be
exemplified when the potentially bidentate 1,10-
bis(diphenylphosphino)ferrocene (dppf) is used as the
* Corresponding authors. Tel.: +65-68742677; fax: +65-67791691.
E-mail addresses: chmgohly@nus.edu.sg (L.Y. Goh), andyhor@
nus.edu.sg (T.S.A. Hor).
0022-328X/$ - see front matter Ó 2004 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2004.03.022

X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
1979
[Ru(dppf)(C3H5)(C6F5O2)]
[18],
[RuCl(CO)(dppf)
arene
arene
Cl
(PPh3)]BF4 and [RuCl(CO)(dppf)(CH3CN)]2(BF4)2
[19]. In this paper we report complexes obtained by
chloro substitution in [CpRu(dppf)Cl] (1) and
[(HMB)Ru(dppf)Cl](PF6) (3), and structural variations
in response to the aromatic ring ligand.
Cl
Cl
Cl
Cl
Cl
P
Ru
Ru
+ dppf
Ru
Ru
Cl
P
Cl
arene
arene
Scheme 2.
partial cleavage required for the conversion of g2-dppf
to l-dppf in the dinuclear complex. The coordination
site vacated by the chelate opening is taken up by the
incoming thiocyanate. Although the latter can also
function as a bridging ligand, it stays terminal and N-
bonded in this case, thus allowing the dppf to switch its
function to a bridging mode. Complex 5 therefore has
the same structural type (see below) as the bridged
complex [(arene)RuCl2]2(-dppf), which was obtained
directly from a dinuclear precursor, [(arene)RuCl2]2
(arene ¼ p-cymene, HMB, 1,2,3,4-Me4C6H2, 1,2,3,5-
Me4C6H2) through dppf addition (Scheme 2) [10].
2. Results and discussion
2.1. Synthesis
2.1.1. Preparation of [CpRu(dppf)Cl] (1)
[CpRu(dppf)Cl] (1) was obtained as bright yellow
solids in 78% yield from the reaction of [CpRu-
(PPh3)2Cl] with dppf in refluxing toluene, according to
the method of Bruce et al. [9].
2.1.2. Reactions with N-donor ligands
2.1.2.1. With NaNCS. At ambient temperature,
[CpRu(dppf)Cl] (1) reacted with one molar equivalent of
NaNCS in MeOH, giving a yellow precipitate of
[CpRu(dppf)(NCS)] (2) in 80% yield. Similar ligand re-
placement occurred with [(HMB)Ru(dppf)Cl]PF6 (3) in
refluxing MeOH for 23 h to give [(HMB)Ru(dppf)-
(NCS)]PF6 (4) in 88% yield (shown in Scheme 1). With
four molar equivalents of NaNCS, 3 gave rise to the
diruthenium compound [(HMB)Ru(NCS)2]2(l-dppf) (5)
in 67% yield. The loss of chelating dppf can be diag-
nosed by NMR (1H and 31P{1H}). Complex 5 can be
independently synthesized (70% yield) from 4 with a
stoichiometric excess of NaNCS. In contrast, 2 is inert
towards excess NaNCS; this is possibly due to the
greater electron-donating capability of the Cp ligand
which results in stronger Ru–P bonds, thus preventing
2.1.2.2. With CH3CN. It is well established that the
chloro ligands in Cp- or arene-ruthenium complexes can
be abstracted by silver salts, giving solvento derivatives
which can be isolated or allowed to react in situ with
selected substrates [20]. We noted that [Cp*Ru(dppf)Cl]
(Cp* ¼ g5-C5Me5) in CH3CN in the presence of AgBF4
gave the solvento complex [Cp*Ru(dppf)(CH3CN)]BF4,
which could be used as a precursor to substitution
products [14]. Here, we are interested in the acetonitrile
derivatives of 1 and 3 to allow a comparison of their
chemical reactivities. It was found that the chloro ligand
in 1 was easily abstracted with NaBPh4 in CH3CN
within 1 h at room temperature to give [CpRu(dppf)-
(CH3CN)]BPh4 (6) in 80% yield; the analogous reaction
of 3 with NH4PF6 in CH3CN had to be performed at
reflux for 24 h, giving [(HMB)Ru(dppf)(CH3CN)](PF6)2
(7) in 62% yield (Scheme 3). This reactivity difference
probably arises from a greater resistance to remove an
NaNCS
Ru
Ru
P
P
Cl
NCS
P
(2)
P
(1)
+
+
NaBPh4
Ru
P
Ru
P
BPh4
P
P
PF
6
NCCH3
Ru
P
Cl
CH3CN, r.t.
P
Cl
(1)
(3)
(6)
2+
+
NaNCS
Ru
Ru
+
NCS
SCN
P
P
NCS
SCN
NH4PF6
(PF6)2
(5)
PF6
Ru
P
Ru
P
P
P
CH3CN, reflux
Cl
NCCH3
PF
Ru
6
P
NCS
P
(7)
(4)
(3)
Scheme 1.
Scheme 3.

1980
X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
anionic ligand (Clꢁ) from a monocationic core in 3, as
compared to a neutral core in 1.
S
P
P
NaS2CNEt2
S
Ru
Ru
P
+
free dppf
P
Cl
S
2.1.3. Reactions with monophosphines
S
(1)
(11)
Complex 1 undergoes chloro-substitution with the
phosphines PMe3 and PMe2Ph to give high yields of the
expected monomeric cationic complexes [CpRu(dppf)
(PMe3)]þ (8) and [CpRu(dppf)(PMe2Ph)]þ (9), isolated
as their PFꢁ6 salts after metathesis with NH4PF6
(Scheme 4). In contrast, the same reaction of
[(HMB)Ru(dppf)Cl]PF6 (3) with one or two molar
equivalents of PMe2Ph in CH3CN, resulted in
displacement of dppf to give the complex [(HMB)
Ru(PMe2Ph)2Cl]PF6 (10) and free dppf (Scheme 5).
Et
S
NaS2CNEt2
Ru
Ru
PPh2
C
N
Ph2P
H2C
Et
S
Ph2P
H2C
Cl
PPh2
C
C
H2
H2
Scheme 6.
2.1.4. With S-donor ligands
chelating dithiocarbamates into the coordination
sphere. Similar loss of the Cp ligand on 1 was not ex-
pected due to the anionic nature of the Cp ligand. We
have previously reported a direct synthesis of 12 from
the reaction of [Ru(S2CNEt2)2(PPh3)2] with dppf ligand
in 80% yield [22].
2.1.4.1. With NaS2CNEt2. The reaction of 1 with slightly
more than one molar equivalent of sodium diethyl di-
thiocarbamate, NaS2CNEt2, in MeOH under reflux
gave a yellow dinuclear complex [CpRu(S2CNEt2)2]2(l-
dppf) (11) (75% yield). Like the thiocyanate complex 5,
the formation of 11 involved halide loss and release of a
free dppf ligand, with the concomitant change from
chelating g2- to a l-bonding mode for dppf (Scheme 6).
In comparison, the analogous reaction of [CpRu(dp-
pe)Cl] was reported to give the mononuclear complex
[CpRu(dppe)(S2CNEt2)] [21] (Scheme 6). The ability for
dppf to take to bridging allows the dithiocarbamate to
adopt its usual chelating mode.
A similar reaction of [(HMB)Ru(dppf)Cl]PF6 (3)
with NaS2CNEt2 led to a product mixture from which
[Ru(S2CNEt2)2(dppf)] (12) was separated in 26% yield
from free hexamethylbenzene ligand and other non-
isolable unstable products. The formation of 12 resulted
from loss of halide and an unexpected cleavage of the
arene ligand in 3 (Scheme 7). The loss of arene ligand is
electronically compensated by the introduction of two
2.1.4.2. With elemental sulfur. The reactions of 1 and 3
with elemental sulfur have also been studied. An ambi-
ent temperature reaction of 1 with S8 in the presence of
NaBPh4 gave deep-green solids of dirutheniumIII
[{CpRu(dppf)}2(l2-S2)](BPh4)Cl (13) in 69% yield
(Scheme 8). The microanalytical data and X-ray dif-
fraction analysis (see below) both show the presence of
the ‘‘mixed’’ anions, which was not expected in the
presence of excess NaBPh4. Thus Ru(II) in 1 has been
oxidized to Ru(III) giving the 34e disulfide species 13.
Rauchfuss and co-workers had prepared the bis(PPh3)
analogue of 13 from the reaction of CpRu(PPh3)2Cl
with S8 in the presence of AgBF4 [23a] or the
air-oxidation of CpRu(PPh3)2SH and of [CpRu(PPh3)2-
(H2S)]þ [23b].
+
S
+
P
S
NH4PF6
NaS2CNEt2
Ru
S
L=PMe3 (8)
+ free HMB + ...
+
L
P
-
Ru
P
S
Ru
P
PF6
Ru
P
L
P
L=PMe2Ph (9)
P
Cl
Cl
P
(12)
(1)
(3)
Scheme 4.
Scheme 7.
+
2+
+
P
S
P
S8, NaBPh4
CH2Cl2
RuIII
RuIII
P
-
+
free dppf
NH4PF6
Ru
P
PF6
PF6
Ru
+ PMe2Ph
Ru
(BPh4)Cl
P
Cl
P
Cl
S
Cl
PhMe2P
PMe2Ph
P
P
(1)
(13)
(3)
(10)
Scheme 5.
Scheme 8.

X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
1981
Instead of undergoing loss of halide ligand as in 1, the
arene complex [(HMB)Ru(dppf)Cl]PF6 (3) reacted with
loss of dppf in the presence of NH4PF6 in CH3CN to
give [(HMB)Ru(CH3CN)2Cl]PF6 (14) as an orange solid
in 63% yield and free dppf(S2) (30% yield) [23] as a
yellow-solid, which was identified via its elemental
analysis together with its NMR and FAB-MS spectra
(Scheme 9). Complex 14 could also be obtained from the
reaction of [(HMB)RuCl2]2 with NH4PF6 in CH3CN in
90% yield [11]. The arene ligand appears to protect the
metal from oxidation. Instead, the dppf ligand is oxi-
dized and cleaved. Oxidative sulfurization of coordi-
nated dppf with elemental sulfur has been observed in
Pt(dppf)2 at room temperature (Scheme 10) [24]. Con-
version of free dppf to dppf(S2) usually requires thermal
activation, e.g. in refluxing 1-butanol [25]. Such con-
version however could be catalyzed by metal under
ambient condition; for example, through the insertion of
S into Ru–P bond, prior to departure of the labile
dppf(S2) ligand.
corresponding resonance for the (l-dppf)(HMB)Ru
complex 5 appears as a broad unresolved multiplet,
presumably due to fluxionality. The 31P resonance of
dppf of the CpRu(II) complexes are observed at d 46.1–
49.8, with those of complexes 8 and 9 appearing as
doublets due to P–P coupling (J ¼ 42 Hz) with the
monophosphine co-ligand, viz. PMe3 and PMe2Ph, re-
spectively. Correspondingly, the PMe3 and PMe2Ph
signals are seen as triplets due to coupling to the two P
atoms of dppf. While the 31P resonances of the dppf
ligand in the (arene)Ru complexes 4 and 7 are observed
within a narrow range (d 38.4, 34.2), that of (l-dppf) 5 is
found in a much higher field (d 27.3).
The FABþ-mass spectra of the CpRu complexes and
(HMB)Ru complexes 4, 10 and 14 display the corre-
sponding parent Mþ ions; however, the mother ions are
not observed for the (l-dppf) (arene)Ru complex 5 and
the complex 7, indicating that the bis(CH3CN) mono-
cationic complex 14 is more stable than the mono-
(CH3CN) dicationic complex 7 in the FABþ mass beam.
Infrared spectra (KBr) show strong bands due to
mCBN and mC–S of the NCS ligand: 2 (2105 and 697
cmꢁ1), 4 (2100 and 698 cmꢁ1) and 5 (2106 and 699
cmꢁ1). In comparison, it is noted that the mCBN
stretching frequencies in [CpRu(SbPh3)(py)(NCS)] [26],
(Bu4N)2[Ru(dcpyH)2(NCS)2] [27] and [Ru(NCS)(NO)-
(bpy)(py)2](PF6)2 [28] were found at 2030, 2120 and
2097 cmꢁ1, respectively, with mC–S at 808, 780 cmꢁ1 and
in the mPF6 region, respectively. The mCBN stretching
vibration of coordinated acetonitrile is seen at 2259
cmꢁ1 in 6, 2363 cmꢁ1 in 7 and 2359 cmꢁ1 in 14. The
dithiocarbamate complexes 11 and 12 show m(CN) at
1486/1485 cmꢁ1, m(NC2) at 1146/1144 cmꢁ1 and m(CS) at
2.2. Spectral characteristics
Details of the spectral features of the product com-
plexes are given in Section 4. Only some significant
comparisons are noted here. Except for the disulfur-
bridged paramagnetic CpRu(III) complex 13, all the
CpRu(II) complexes show a sharp resonance for the g5-
C5H5 protons in the range d 4.29–4.75, while the (are-
ne)Ru(II)dppf complexes show the Me resonance of
HMB as singlets at d 1.51–1.77 in the proton NMR
spectrum. The non-dppf (arene)Ru complexes 10 and 14
show proton signals for Me of HMB at d 1.67 and 2.13,
respectively. The C5H4 protons of the dppf ligands are
observed in the range d 3.96–4.96 as four equal-intensity
peaks for the CpRu complexes 2 and 9 and for the
(HMB)Ru complexes 4 and 7, or as a pair of peaks of
equal intensity for the CpRu complexes 6, 8 and 11. The
792/695 cmꢁ1
.
2.3. X-ray structural studies
2.3.1. The mononuclear complexes
In all cases, selected geometric parameters are given
in their respective figure captions.
Since the X-ray single-crystal structure of 1 has not
been reported, an analysis is included here for compar-
ison with chloro-substituted derivatives. The molecular
structure is given in Fig. 1. It shows a mononuclear
Ru(II) capped by an g5-Cp ring, a chelating g2-dppf
and a terminal chloride, thus completing a three-legged
piano-stool configuration. The Ru–Cl bond distance of
S
+
+
P
PPh2
S8,NH4PF6
CH3CN
NCCH3
NCCH3
-
-
Ru
PF6
PF6
Ru
Cl
+
Fe
P
Cl
PPh2
S
(3)
(14)
(dppf)S2
Scheme 9.
ꢀ
2.4446(12) A and Ru–P distances of 2.2871(12) and
ꢀ
2.2852(12) A in 1 are virtually indistinguishable from
those found in the dppe analogue, [CpRu(dppe)Cl]
ꢀ
[29,30] (2.4466(7), 2.2688(7) and 2.2863(7) A, respec-
S
S
S
S
P
P
S8
P
P
P
P
tively) [30]. The larger bite size of dppf forces a wider P–
Ru–P chelate angle (95.01(4)° in 1 compared with
83.48(2)° in [CpRu(dppe)Cl]. The conformation of the
Cp rings of dppf is best described as synperiplanar
eclipsed as reflected in the torsion angle defined by
+ (dppf)S2
Pt
Pt
benzene
Scheme 10.

1982
X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
Fig. 1. Molecular structure of [CpRu(dppf)Cl] (1). Hydrogen atoms
ꢀ
are omitted for clarity. Selected geometric parameters (A, °): Ru–Cl
2.4446(12), Ru–P1 2.2871(12), Ru–P2 2.2852(12), Cl–Ru–P1 93.18(4),
Cl–Ru–P2 89.47(4) and P1–Ru–P2 95.01(4).
Fig. 2. Molecular structure of [CpRu(dppf)(NCS)] (2). Hydrogen at-
ꢀ
oms are omitted for clarity. Selected geometric parameters (A, °): Ru–
P1 2.2978(8), Ru–P2 2.2922(7), Ru–N1 2.076(3), P1–Ru–P2 96.77(3),
P1–Ru–N1 88.91(7), P2–Ru–N1 87.22(7), Ru–N1–C1 173.1(2), N1–
C1–S1 178.1(3).
P-ring centroids-P of 4.81(7)° [7]. The Cp rings are
symmetrically disposed about the Fe atom so that both
Fe-ring centroid distances are 1.648(2), the ring cent-
roids subtend an angle of 178.26(12)° at Fe and the
dihedral angle between the two Cp rings is 3.4(3)°.
The molecular structure of 2 is shown in Fig. 2. The
compound co-crystallized with a solvent molecule of
acetone so that the ratio of complex to acetone is 1:1.
This mononuclear structure is similar to that of 1 with
NCS replacing the chloride. The closest available
structure for comparison is that of [CpRu(PPh3)2(NCS)]
[31] which also features an N-bound NCS ligand. The
Ru–N bond distances are indistinguishable in the two
structures but the Ru–P bond distances in 2 (2.2978(8)
bond parameters with those of the chloro complex 1 and
the CH3CN solvento complexes 6 and 7. It is shown that
a plane of symmetry through Ru and Cl bisects the
ꢀ
HMB ring in 14. The Ru–Cl bond (2.3975(8) A) is
shorter and presumably stronger than that in 1
ꢀ
(2.4446(12) A). The Ru–N(CH3CN) distance (2.072(2)
ꢀ
A) is slightly longer than those in 6 and 7 (2.0487(16)
ꢀ
and 2.018(7) A, respectively). The C–N bond length of
CH3CN is 1.1329(3), slightly shorter than those in 6 and
7.
Likewise the molecular structures of the cations of 8
and 9, shown in Fig. 5, belong to the monomeric type
described above, with a similar geometry at the Ru
center. The Ru–P distances (from 2.3436(11) and
ꢀ
and 2.2922(7) A) are significantly shorter than those in
ꢀ
[CpRu(PPh3)2(NCS)] (2.318(1) and 2.323(2) A) [31]. The
distance between the ring centroid of the Ru-bound Cp
ꢀ
ring and the metal is 1.8596(14) A. The conformation of
the dppf-Cp rings is synperiplanar eclipsed; torsion angle
ꢀ
ꢀ
2.3288(10) A in 9 to 2.357(2) and 2.3244(18) A in 8) are
shorter than those of the Cp*Ru(dppf) complex, e.g.
2
ꢀ
0.89(5)°, the Fe-ring centroid distances are 1.6414(16)
and 1.6385(15) A, the angle subtended at Fe is
2.408(3) and 2.390(3) A in [Cp*Ru(dppf)(g -O2)]BF4
[14], but slightly longer than those of the ruthenium
carboxylate phosphine complexes. The Ru–C distances
between Cp and Ru metal increase in the order of
9 > 8 > 6, indicating that the more bulky ligands have
decreased the bond length.
ꢀ
176.43(8)° and the dihedral angle between the two Cp
rings is 3.7(2)°.
The molecular structures of [CpRu(dppf)(CH3CN)]þ
(6) and the dicationic HMB analogue 7 are similar and
are given in Figs. 3(a) and (b). They possess a geometry
at Ru similar to that adopted by 1 and 2 above, namely
with capping Cp/HMB, g2-dppf and N-coordinated
CH3CN completing the three-legged piano-stool con-
figuration. The CBN bond length are 1.143(2) and
2.3.2. The dinuclear complexes
As for the mononuclear complexes, selected geomet-
ric parameters are given in the figure captions.
The molecular structure of 5 is shown in Fig. 6. The
molecule has crystallographic 2-fold symmetry such that
the Fe atom lies on this axis and the structure co-crys-
tallizes with a solvent water molecule that also lies on a
ꢀ
1.151(10) A in 6 and 7, respectively.
The molecular structure of the cation of 14 (Fig. 4) is
included here to provide a comparison of some of its

X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
1983
Fig. 3. (a) Molecular structure of [CpRu(dppf)(CH3CN)]þ (6 cation). Hydrogen atoms are omitted for clarity. Selected geometric parameters (A, °):
ꢀ
Ru1–P1 2.3243(5), Ru1–P2 2.3206(5), Ru1–N1 2.0487(16), P1–Ru1–P2 98.702(18), P1–Ru1–N1 91.04(4), P2–Ru1–N1 87.89(4). (b) Molecular
structure of [(HMB)Ru(dppf)(CH3CN)]2þ (7 cation). Hydrogen atoms are omitted for clarity except in CH3CN. Selected geometric parameters (A,
ꢀ
°): Ru1–P1 2.368(2), Ru1–P2 2.388(2), Ru1–N1 2.018(7), P1–Ru1–P2 92.49(8), P1–Ru1–N1 88.78(19), P2–Ru1–N1 87.38(18).
of a bridging dppf ligand and two N-bound thiocyanate
ligands. The bonding mode of dppf in this structure
contrasts with its chelating mode in the aforementioned
structures of 1 and 2. The Ru–N bond distances of
ꢀ
2.044(4) and 2.045(5) A are shorter than that in 2
ꢀ
(2.076(3) A) and the Ru–P bond distances of 2.3540(12)
ꢀ
A are the longest of these three structures. The overall
structure for 5 is similar to that reported for [(g6-
Me4C6H2)RuCl2]2(l-dppf) [10] allowing for differences
in chemistry and the different crystallographic symme-
try; the latter molecule is situated about a centre of in-
ꢀ
version. The Ru atom is separated by 1.741(3) A from
Fig. 4. Molecular structure of [(HMB)Ru(CH3CN)2Cl]þ (14 cation).
Hydrogen atoms are omitted for clarity. Selected geometric parameters
the ring centroid of the HMB ligand. The dppf-Cp rings
have an almost perfect antiperiplanar staggered confor-
mation (P-ring centroid-P torsion angle is )176.1(2)°) in
ꢀ
(A, °): Ru1–Cl1 2.3975(8), Ru1–N1 2.072(2), N1–C7 1.1329(3), N1–
Ru1–Cl1 85.22(6).
ꢀ
which the Fe atom is 1.647(2) A from each of the ring
centroids, the angle subtended at Fe by the ring cent-
roids is 178.7(2)°, and the dihedral angle between the
two Cp rings is 4.8(1)°.
2-fold axis so that the ratio of complex to water is 1:1.
The Ru atom in 5 also adopts a pseudo-octahedral ge-
ometry, being coordinated to a HMB ring, one P atom
Fig. 5. (a) [CpRu(dppf)(PMe3)]þ (8 cation). Hydrogen atoms are omitted for clarity. Selected geometric parameters (A, °): Ru1–P1 2.3244(19),
ꢀ
Ru1–P2 2.3399(18), Ru1–P3 2.357(2), P1–Ru1–P2 98.90(7), P1–Ru1–P3 94.42(7), P2–Ru1–P3 98.10(6). (b) Molecular structure of
[CpRu(dppf)(PMe2Ph)]þ (9 cation). Hydrogen atoms are omitted for clarity. Selected geometric parameters (A, °): Ru1–P1 2.3436(11), Ru1–P2
2.3288(10), Ru1–P3 2.3432(10), P1–Ru1–P2 97.44(4), P1–Ru1–P3 97.64(4), P2–Ru1–P3 95.58(4).
ꢀ

1984
X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
(L2 ¼ dppe or L ¼ PPh3) with sodium dithiocarbamate
[21,32]. The dithiocarbamate ligands are in their usual
g2-chelate mode [33–35] with small bites (ca. 72°) at Ru.
An important observation is that the bulky bridging
dppf is relatively strongly coordinated to Ru (2.2616(11)
ꢀ
and 2.2692(11) A), the Ru–P bond lengths being sig-
nificantly shorter than those of other CpRu(dppf)
ꢀ
complexes (ca. 2.32 A). In the formation of 11 from
[CpRu(dppf)Cl], dppf has changed from g2- to l-
bridging bonding mode, which does not happen with
less bulky mono or diphosphines, e.g. in complex
[CpRu(dppe)(g1-S2CNEt2)] (Scheme 5) [21]. Another
feature of interest in 11 is the degree of double-bond
character present in central C–N bond in the dithio-
carbamate ligand, these bonds (C1–N1, C6–N2) exhibit
ꢀ
partial double-bond character (1.339(6) and 1.333(6) A),
which could be found in the structure of [CpRu-
(PPh3)(g2-S2CNMe2)] [32].
The molecular structure of the dication [{CpRu
(dppf)}2(l-S2)]2þ of 13 possessess ruthenium(III) centers
linked by a disulfide bridge (l-S22ꢁ), the Ru–S–S–Ru
dihedral angle being 145.8°. (Fig. 8) Each sulfur, to-
gether with the chelating dppf and g5-Cp, completes a
piano-stool arrangement at the metal. The syn-g1:g1
mode adopted by the disulfide necessitates a syn ar-
rangement of the two dppf, and the two C5 rings, across
the bridge. The interplanar angle between the Cp rings is
Fig. 6. Molecular structure of [(HMB)Ru(NCS)2]2(l-dppf) (5). Hy-
drogen atoms are omitted for clarity. Selected geometric parameters
ꢀ
(A, °): Ru–P1 2.3543(12), Ru–N1 2.044(4), Ru–N2 2.045(5), P1–Ru–
N1 85.11(12), P1–Ru–N2 86.63(13), N1–Ru–N2 89.51(18), Ru–N1–C1
172.5(4), Ru–N2–C2 164.5(5), N1–C1–S1 178.0(5), N2–C2–S2
179.4(7).
ꢀ
83.8°. The Ru–S bond lengths (2.330(2) and 2.334(2) A)
are in the normal range of Ru–S (2.30 A) [36]. The S(1)–
ꢀ
ꢀ
S(2) bond length 2.015(2) A lies between the values for
ꢀ
ꢀ
S@S in free S2 (1.887 A) [37] and S–S in H2S2 (2.055 A)
The molecular structure of the diruthenium complex
11 (Fig. 7) shows the dithiocarbamate ligands chelated
to the Ru center through two S donors, significantly
different from the commonly monodentate mode in
CpRu phosphine complexes, such as [CpRu(L)2
(S2CNEt2)] synthesized by reactions of [CpRu(L)2Cl]
ꢀ
or Me2S2 (2.038 A) [38,39]. Based on additional elec-
trochemical and EPR data, Rauchfuss and co-workers
ꢀ
[23a] had ascribed the short S–S bond (1.962(4) A) and
ꢀ
also short Ru–S bond (2.208(3) A) in the analogous
[{CpRu(PPh3)2}2(l2-S2)](SbF6)2 complex to delocalized
ꢀ
Fig. 7. Molecular structure of [{CpRu(S2CNEt2)}2(l-dppf)] (11). Hydrogen atoms are omitted for clarity. Selected geometric parameters (A, °): Ru1–
P1 2.2616(11), Ru2–P2 2.2692(11), Ru1–S1 2.3926(12), Ru1–S2 2.3866(11), Ru2–S3 2.4072(13), Ru2–S4 2.3957(12), C1–N1 1.339(6), C6–N2
1.333(6), C2–N1 1.521(7), C1–S1 1.716(5), C1–S2 1.691(5), C6–S3 1.722(5), C6–S4 1.705(5), S1–Ru1–S2 72.17(4), S3–Ru2–S4 71.64(4), P1–Ru1–S1
89.88(4), P1–Ru1–S2 94.04(4), P2–Ru2–S3 86.17(4), P2–Ru2–S4 93.35(4), S1–C1–S2 111.4(3), S1–C1–N1 123.9(4), S2–C1–N1 124.5(4), S3–C6–S4
110.2(3), S3–C6–N2 124.4(4), S4–C6–N2 125.3(4).

X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
1985
Fig. 8. Molecular structure of [{CpRu(dppf)}2(l2-S2)]2þ (13 cation). Hydrogen atoms are omitted for clarity. Selected geometric parameters (A, °):
Ru1–S1 2.330(2), Ru2–S2 2.334(2), S1–S2 2.015(2), Ru1–P1 2.310(2), Ru1–P2 2.307(2), Ru2–P3 2.329(2), Ru2–P4 2.306(2), P1–Ru1–P2 97.76(6), P3–
Ru2–P4 96.37(6), S1–Ru1–P1 89.73(6), S1–Ru1–P2 88.79(6), S2–Ru2–P3 89.25(6), S2–Ru2–P4 88.72(6), S1–S2–Ru2 108.31(8), S2–S1–Ru1
110.00(8).
ꢀ
p-bonding in the Ru2S2 core, facilitated by the strong
p-donor capability of the S2 ligand. It is noted that
comparably short S–S bonds have been found in
[(l2-S2)(Cp*Ru)2(l3-S)(l2-S)2MS] (M ¼ W, Mo) (S–S
4. Experimental
4.1. General
ꢀ
1.991(7) A) by Hidai and co-workers [36],
All reactions were performed under dry nitrogen us-
ing Schlenk techniques. Solvents were freshly distilled
from standard drying agents. 1H and 31P{1H} NMR
spectra were recorded on a Bruker ACF300 FT NMR
spectrometer, with chemical shifts referenced to residual
non-deutero solvent and external H3PO4, respectively.
IR spectra were obtained a KBr disk on a Perkin–Elmer
1600 spectrophotometer. Mass spectra were obtained on
a Finnigan MAT95XL-T spectrometer. All elemental
analyses were performed in-house.
III
ꢀ
[{Ru (NH3)5}2(l-S2)]Cl4 ꢀ 2H2O (S–S 2.014(1) A) by
Elder and Trkula [40] and [{LRu(acac)}2(l-S2)](PF6)2
(L ¼ 1,4,7-trimethyl-1,4,7-triazacyclononane,
S–S
ꢀ
1.989(2) A) by Wieghardt and co-workers [41].
3. Conclusions
With the donor ligands under investigation,
[CpRu(dppf)Cl] (1) gives mononuclear chloro-substi-
tuted products, except in the reaction with S8 which
results in a l-S2-bridged dinuclear species. With the
same donor ligands, [(HMB)Ru(dppf)Cl]PF6 (3) un-
dergoes (i) chloride-only substitution with CH3CN or
RuCl3 ꢀ 3H2O was obtained from Aldrich, and PMe3,
PMe2Ph, PPh3, dppf and NaS2CNEt2 from Merck.
[CpRu(PPh3)2Cl] [42], [(HMB)RuCl2]2 [43] and
[(HMB)Ru(dppf)Cl]PF6 [10] were prepared by pub-
lished methods. All other reagents were obtained
commercially.
NCSꢁ,
followed by further reaction of [(HMB)
Ru(dppf) (NCS)]PF6 (4) to form [(HMB)Ru(NCS)2]2(l-
dppf) (5), (ii) arene cleavage with S2CNEtꢁ2 , giving
[Ru(dppf) (S2CNEt2)2] (12), or (iii) dppf cleavage, re-
sulting in [(HMB)Ru(PMe2Ph)2Cl]PF6 (10) with
PMe2Ph and [(HMB)Ru(CH3CN)2Cl]PF6 (14) together
with (dppf)S2 with S8. These reactions suggest that de-
pending on synthetic conditions and ligand environ-
ment, one or several of the following can take place, viz,
ligand substitution, anionic exchange, metal oxidation
and ligand oxidation. The use of dppf as a supporting
ligand introduces an additional dimension in the for-
mation of dinuclear species. These coordination possi-
bilities have prompted us to use this system for further
synthetic investigations.
4.2. Preparation of complexes
4.2.1. [CpRu(dppf)Cl] (1)
Complex [CpRu(dppf)Cl] (1) was prepared from
[CpRu(PPh3)2Cl] and dppf according to the method of
Bruce et al. [9], who obtained 1 after 16 h reflux in
benzene.
A solution of [CpRu(PPh3)2Cl] (0.369 g, 0.51 mmol)
and dppf (0.306 g, 0.55 mmol) in toluene (30 ml) was
heated under reflux for 12 h. Concentration of the so-
lution followed by addition of hexane gave a bright-
yellow solid of [CpRu(dppf)Cl] (1) which was washed
twice with toluene and hexane (1:2, v/v) and ether, re-
spectively, and dried in vacuo (0.301 g, 0.40 mmol, 78%

1986
X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
yield). Anal. Calc. for C39H33ClP2FeRu: C, 62.0; H, 4.4;
Cl, 4.7; P, 8.2. Found: C, 62.1; H, 4.3; Cl, 4.6; P, 8.3%.
NMR (CDCl3): 1H: d 4.11 (s, 5H, C5H5), 4.03, 4.24, 4.32
and 5.19 (each s, total 8H, C5H4), 7.16 (s, 1H, Ph), 7.19
(s, 1H, Ph), 7.29–7.34 (m, 8H, Ph) and 7.39–7.45 (m,
filtrate was concentrated to ca. 2 ml and ether (3 ml)
added; after
at 0–5 °C, yellow solids of
1
h
[(HMB)Ru(NCS)2]2(l-dppf) (5) (13 mg, 0.01 mmol,
67%) were obtained. Anal. Calc. for C62H64N4P2-
S4FeRu2: C, 56.7; H, 4.9; N, 4.3; S, 9.8. Found: C, 56.7;
1
1
10H, Ph); 31P{1H}: d 45.8 (s). NMR (C6D6): H: d 4.16
H, 4.8; N, 4.2; S, 9.8%. NMR (CDCl3, 300 K): H: d
(s, 5H, C5H5), d 3.71, 3.94, 4.24 and 5.62 (C5H4 of
dppf); 31P{1H}: d 46.2. FABþ-MS: m/z 756 [M]þ, 721
[M–Cl]þ. IR (KBr, cmꢁ1): m 1433, 1090, 695, 514, 505
and 479.
1.77 (s, 36H, C6Me6), 4.10 (c.m, unres., 8H, C5H4), 7.50
(c.m with a sharp signal at d 7.41, 20H, Ph); 31P{1H}: d
27.3 (s). FABþ-MS: m/z 701 [M–NCS–dppf]þ. (KBr,
cmꢁ1): m(CBN) 2106 vs, m(C–S) 699m.
A subsequent reaction showed that the reaction was
complete after 4 h in refluxing toluene.
Likewise, a mixture of [(HMB)Ru(NCS)]PF6 (4) (15
mg, 0.02 mmol) and NaNCS (5 mg, 0.06 mmol) in
CH3CN (20 ml) was stirred for 2 days. A yellow sus-
pension was resulted. The mixture was filtered to remove
a yellow precipitate of displaced dppf, diagnosed via 1H
and 31P{1H} NMR spectra. The filtrate was concen-
trated to ca. 1 ml and ether (2 ml) added; after 3 h at 0
°C, yellow solids were collected (9 mg, 0.007 mmol,
70%). Its NMR resonance of dppf and HMB, FAB and
IR spectra are identical to those of 5.
4.2.2. [CpRu(dppf)(NCS)] (2)
To a yellow suspension of 1 (0.037 g, 0.05 mmol) in
MeOH (5 ml), NaNCS (0.008 g, 0.10 mmol) was added
and the mixture was stirred for 6 h. The resultant yellow
suspension was filtered to collect the yellow precipitate
of [CpRu(dppf)(NCS)] (2), which was washed with
MeOH (2 ꢂ 2 ml) and ether (2 ꢂ 2 ml) and dried in va-
cuo (0.031 g, 0.04 mmol, 80% yield). Anal. Calc. for
C40H33NP2SFeRu: C, 61.7; H, 4.3; S, 4.1. Found: C,
61.7; H, 4.35; S, 4.2%. NMR (CDCl3, 300 K): 1H: d 4.30
(s, 5H, C5H5), 4.08, 4.12, 4.26 and 4.35 (each s, 2H,
C5H4), 7.35 and 7.63 (each c.m, total 20H, Ph); 31P{1H}:
d 48.6 (s). FABþ-MS: m/z 779 [M]þ, 721 [M–NCS]þ,
1499 [2M–NCS]þ. IR (KBr, cmꢁ1): m(CBN) 2105s, m(C–
S) 697s.
4.2.4. [CpRu(dppf)(CH3CN)]BPh4 (6) and [(HMB)
Ru(dppf)(CH3CN)](PF6)2 (7)
A reaction of 1 (0.020 g, 0.03 mmol) in CH3CN (20
ml) with NaBPh4 (0.035 g, 1 mmol) for 1 h gave orange
solids of [CpRu(dppf)(CH3CN)]BPh4 (6) (0.036 g, 0.03
mmol, 80% yield). Anal. Calc. for C65H56BNP2FeRu: C,
72.2; H, 5.2; N, 1.3. Found: C, 72.9; H, 5.2; N, 1.4%.
NMR (CDCl3): 1H: d 2.29 (s, CH3CN), 4.30, 4.36 (each
s, total 8H, C5H4), 4.39 (s, 5H, C5H5), 7.41–7.80 (m,
40H, Ph); 31P{1H}: d 46.1 (s). ESIþ-MS: m/z 761 [M]þ,
721 [M–CH3CN]þ ꢀ ESIꢁ-MS: m/z 319 [BPh4]ꢁ. IR
(KBr, cmꢁ1): m(CBN) 2259.
A mixture of [(HMB)Ru(dppf)Cl]PF6 (3) (30 mg, 0.03
mmol) and NH4PF6 (10 mg, 0.06 mmol) in CH3CN (25
ml) was refluxed for 24 h. The orange suspension was
filtered through celite. Concentration of the filtrate to
ca. 2 ml, followed by addition of ether (3 ml) and
cooling at 0–5 °C for 1 h gave orange solids of
[(HMB)Ru(dppf)(CH3CN)](PF6)2 (7) (21 mg, 0.02
mmol, 62%). Anal. Calc. for C48H49F12NP4FeRu. C,
50.2; H, 4.3; N, 1.2. Found: C, 50.3; H, 4.4; N, 1.2%. 1H
NMR (CDCl3): d 1.60 (s br, 18H, C6Me6), 2.22 (s, 3H,
CH3CN), 3.97, 4.09, 4.24 and 4.94 (each s, total 8H,
C5H4), 7.42, 7.54, 7.71 and 7.82 (each s br, total 20H,
Ph). 31P{1H} NMR (CDCl3): d 34.2 (s, dppf), )144
(septet, PF6). FABþ-MS: m/z 655 [M–C6Me6-CH3CN]þ
and unassignable mass fragments 693 and 855. IR (KBr,
cmꢁ1): m(CBN) 2363s, m(PF6) 834s and 556s.
4.2.3. [(HMB)Ru(dppf)(NCS)]PF6 (4) and [(HMB)
Ru(NCS)2]2l-dppf) (5)
A mixture of [(HMB)Ru(dppf)Cl]PF6 (3) (68 mg, 0.07
mmol) and NaNCS (6 mg, 0.07 mmol) was refluxed in
MeOH (10 ml) for 23 h, resulting in an orange yellow
suspension. The solids [(HMB)Ru(dppf)(NCS)]PF6 (4)
were filtered, washed with MeOH and ether and dried in
vacuo. The filtrate was evacuated to dryness, extracted
with CH2Cl2 (5 ꢂ 2 ml). The combined extracts were
filtered to remove sodium salt. The residue was recrys-
tallized in CH2Cl2-hexane (1:4) to give an orange solid
of 4 (total yield, 63 mg, 0.06 mmol, 88%). Anal. Calc. for
C47H46F6NP3SFeRu: C, 55.3; H, 4.5; N, 1.4; S, 3.1.
Found: C, 55.4; H, 4.6; N, 1.3; S, 3.4%. NMR (CDCl3,
300 K): 1H: d 1.58 (s, 18H, C6Me6), 4.04, 4.11, 4.35 and
4.76 (each s, total 8H, C5H4), 7.33, 7.51 and 7.67 (each
c.m, unres., total 20H, Ph); 31P{1H}: d 38.4 (s, dppf),
)144 (PF6). FABþ-MS: m/z 876 [M]þ, 818 [M–SCN]þ,
714 [M–C6Me6]þ, 655 [M–C6Me6–SCN]þ. FABꢁ-MS:
m/z 145 [PF6]ꢁ. IR (KBr, cmꢁ1): m(CBN) 2100 vs, m(C–
S) 698m, m(PF6) 813s, 474m.
A similar mixture of [(HMB)Ru(dppf)Cl]PF6 (3)
(30 mg, 0.03 mmol) and excess NaNCS (5 mg,
0.07 mmol) in CH3CN (25 ml) was stirred for 2–3 days.
A yellow suspension resulted. The mixture was fil-
tered to remove a yellow precipitate of displaced
dppf, diagnosed via 1H and 31P{1H} NMR spectra. The
4.2.5. [CpRu(dppf)(L)]PF6 (L ¼ PMe3 (8), PMe2Ph
(9)) and [(HMB)Ru(PMe2Ph2)2Cl]PF6 (10)
A reaction of 1 (0.057 g, 0.08 mmol) with PMe3 (0.1
ml, 0.11 mmol) and NH4PF6 (0.017 g, 0.1 mmol)
in MeOH (10 ml) gave yellow solids of
[CpRu(dppf)(PMe3)]PF6 (8) (0.059 g, 0.06 mmol, 84%

X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
1987
yield). Anal. Calc. for C42H42F6P4FeRu ꢀ CH2Cl2: C,
50.3; H, 4.3; F, 11.1; P, 12.0. Found: C, 50.0; H, 4.3; F,
12.0; P, 12.1%. NMR (CDCl3): 1H: 1.39 (d, 9H, PMe3);
4.38 and 4.51 (each s, 4H, C5H4); 4.75 (s, 5H, C5H5);
7.26–7.42 (m, 20H, Ph); 31P{1H}: d 49.8 (d, J(PP) ¼ 42
Hz, dppf); )10.1 (t, J(PP) ¼ 42 Hz, PMe3); )144 (septet,
J(PF) ¼ 710 Hz, PF6). IR (KBr, cmꢁ1): m(PF6) 841s,
556s. FABþ-MS: m/z 797 [M]þ, 721 [M–PMe3]þ. FABꢁ-
MS: m/z 145 [PF6]ꢁ.
(CS) 792m; m(others) 2971w, 2928w, 2374w, 2336w,
1647wbr, 1430m, 1268s, 1090s, 1028s, 685s, 534msh,
469s.
A
mixture of 3 (29.4 mg, 0.03 mmol) and
NaS2CNEt2.3H2O (9.1 mg, 0.04 mmol) was refluxed for
24 h in MeOH (15 ml). The yellow solids of [Ru(S2C-
NEt2)2(dppf)] (12) were filtered, washed with MeOH
and ether, and evacuated to dryness (5 mg, 0.005 mmol,
26%). Anal. Calc. for C44H48N2P2S2FeR: C, 55.5; H,
1
Likewise, a reaction of 1 (0.061 g, 0.08 mmol) with
PMe2Ph (0.015 ml, 0.1 mmol) and NH4PF6 (0.018 g,
0.11 mmol) in MeOH (20 ml) gave yellow solids of
[CpRu(dppf)(PMe2Ph)]PF6 (9) (0.068 g, 0.07 mmol,
85% yield). Anal. Calc. for C47H44F6P4FeRu: C, 56.2;
H, 4.4; F, 11.4; P, 12.3. Found: C, 56.0; H, 4.7; F, 11.2;
5.1; N, 2.9. Found: C, 54.7; H, 5.4; N, 2.6%. H NMR
(CDCl3): d 0.98 (s, m1=218 Hz, 12H, CH3), 3.24 (s,
m1=2 ¼ 42 Hz, 2H, CH2), 3.53 (s, m1=2 ¼ 33 Hz, 6H, CH2),
4.20 (s, 2H, C5H4), 4.36 (s, 2H, C5H4), 4.44 (s, 4H,
C5H4), 7.17 and 7.24 (overlapping triplets, J ¼ 7 Hz, 12
H, Ph), 7.68 (s, m1=2 ¼ 26 Hz, 8H, Ph). 31P{1H} NMR
(CDCl3): d 47.7 (s, dppf). FABþ-MS: m/z 952 [M]þ, 804
[M-(S2CNEt2)]þ. IR (KBr, cmꢁ1): m(CN) 1485m; m(NC2)
1144m; m(CS) 695m; m(others) 3052w, 2966w, 2923w,
2869vw, 1428m, 1360w, 1271m, 1214vw, 1082m, 1030m,
905vw, 810w, 744w. Free HMB ligand was diagnosed by
1H NMR and FABþ-MS.
1
P, 11.9%. NMR (CDCl3): H: d 1.66 (d, 6H, PMe2Ph);
4.45 (s, 5H, C5H5); 4.31, 4.38, 4.60 and 4.68 (each s,
total 8H, C5H4); 7.09, 7.33 and 7.39 (each, c.m, total
25H, Ph); 31P{1H}: d 48.7 (d, J(PP) ¼ 42 Hz, dppf); 0.6
(t, J(PP) ¼ 42 Hz, PMe2Ph); )144 (septet, J(PF) ¼ 713
Hz, PF6). IR (KBr, cmꢁ1): m(PF6) 839s, 556s. FABþ-
MS: m/z 859 [M]þ, 721 [M–PMe3]þ. FABꢁ-MS: 145
[PF6]ꢁ.
To a solution of 3 (30 mg, 0.03 mmol) in CH3CN (10
ml) was added PMe2Ph (4 ll, 0.03 mmol) and the mix-
ture was stirred for 8 h. A yellow suspension was re-
sulted. The yellow precipitate, found to be free dppf,
was filtered off. The orange filtrate on concentration
4.2.7. [{CpRu(dppf)}2(l-S2)](BPh4)Cl (13) and
[(HMB)Ru(CH3CN)2Cl]PF6 (14)
To a yellow solution of 1 (0.053 g, 0.07 mmol) in
CH2Cl2 (10 ml), NaBPh4 (0.086 g, 0.25 mmol) and ele-
mental sulfur (0.017 g, 0.52 mmol) were added and the
mixture was stirred for 9 h. The deep green resultant
suspension solution was filtered to remove the sodium
salts. The filtrate was evacuated to dryness and the
solids extracted with toluene to remove excess sulfur and
unreacted 1. The residue was dissolved in ca. 2 ml of
acetone and hexane was added, giving deep green solids
of [{CpRu(dppf)}2(l2-S2)](BPh4)Cl (13) (0.045 g, 0.024
to ca.
3
ml gave orange red crystals of
[(HMB)Ru(PMe2Ph)2Cl]PF6 (10) (13 mg, 60%). Anal.
Calc. of C28H40ClF6P3Ru: C, 46.7; H, 5.6; P, 12.9.
1
Found: C, 46.5; H, 5.6; P, 12.0%. H NMR (CDCl3): d
1.67 (s, 18h, C6Me6), 1.92 (d, J ¼ 6 Hz, 12H, PMe2Ph),
7.49–7.71 (m, 10H, Ph). 31P{1H} NMR (CDCl3): d 6.6
(s, PMe2Ph), )144 (septet, PF6). FABþ-MS: m/z 575
[M]þ. IR (KBr, cmꢁ1): m(PF6) 841s, 557s.
mmol, 69% yield). Anal. Calc. for
C102H86BCl-
Fe2P4Ru2S2: C, 65.9; H, 4.7; B, 0.6; Cl, 1.9; S, 3.5.
Found: C, 65.5; H, 5.1; B, 1.2; Cl, 1.5; S, 3.1%. NMR
(CDCl3): 1H: d 4.07 (vbr, m1=2 ca. 60 Hz, 26H, C5H5 and
C5H4), 6.86 (s, br), 7.02 (s, br) and 7.42–7.57 (m, total,
ca. 60H, Ph). 31P{1H} NMR (CDCl3): no signal. FABþ-
MS: m/z 1506 [M]þ, 721 [CpRu(dppf)]þ. FABꢁ-MS: m/z
319 [BPh4]ꢁ. IR (KBr, cmꢁ1): m 3058w, 2924w, 2362w,
2342w, 1478m, 1432m, 1159msh, 1089s, 1032m, 804m,
745s, 698vs, 621w, 508vs, 470s, 438m.
To a solution of 3 (64 mg, 0.06 mmol) in CH3CN
(10 ml) was added S8 (16 mg, 0.5 mmol S) and the
mixture was stirred for 4 h. A yellow suspension was
resulted. The yellow solids of dppfS2 [34] were removed
by filtration. Concentration of the orange filtrate to ca. 3
ml gave orange red crystals of [(HMB)Ru-
(CH3CN)2Cl]PF6 (14) (10 mg, 63%). Anal. Calc. of
C16H24ClF6N2PRu: C, 36.5; H, 4.6; N, 5.3. Found: C,
36.5; H, 4.5; N, 5.4%. 1H NMR (CD3CN): d 2.13
(C6Me6). FABþ-MS: m/z 381 [M]þ, 340 [M–CH3CN]þ.
FABꢁ-MS: 145 [PF6]ꢁ. IR (KBr, cmꢁ1): m(CBN)
2359m, m(PF6) 841s, 557s.
4.2.6. [{CpRu(S2CNEt2)}2(l-dppf)]
[Ru(dppf)(S2CNEt2)2] (12)
(11)
and
A yellow suspension of 1 (0.064 g, 0.08 mmol) and
sodium diethyldithiocarbamate (0.024 g, 0.11 mmol) in
MeOH (20 ml) was heated under reflux for 10 h. The
resultant orange suspension was filtered to collect the
orange precipitates of [{CpRu(S2CNEt2)}2(l-dppf)]
(11), which were washed twice with methanol and ether
and dried in vacuo. Recrystallization in CH2Cl2/hex
gave orange crystals (0.030 g, 0.025 mmol, 60% yield)
after 1 h at 0 °C. Anal. Calc. for C54H58N2P2S4FeRu2 ꢀ
CH2Cl2: C, 52.1; H, 4.8; N, 2.2; P, 4.9; S, 10.1. Found:
C, 52.2; H, 4.6; N, 2.2, P, 4.5; S, 10.0%. NMR (CDCl3):
1H: d 0.91 (t, J ¼ 7 Hz, 12H, CH3), 3.23 (q, unres., 8H,
CH2), 4.20 and 4.09 (each s, total 8H, C5H4), 4.47 (s,
5H, C5H5), 7.18 and 7.47 (each c.m, total 20H, C6H5);
31P{1H}: d 47.5 (s). FABþ-MS: m/z 1180 [M]þ, 869
[CpRu(dppf)(S2CNEt2)]þ, 721 [CpRu(dppf)]þ, 554
[dppf]þ. IR (KBr, cmꢁ1): m(CN) 1486m; m(NC2) 1146m;

Table 1
Crystal and structure refinement data for 1, 2 ꢀ acetone, 5 ꢀ H2O, 6, 7, 8, 9, 11 ꢀ CH2Cl2, 13 and 14a
Complexes
1
2 ꢀ acetone
43H39Fe-
5 ꢀ H2O
62H66FeN4-
6
7 ꢀ 0.5CH3CN 8 ꢀ 0.5Et2O
49H50:50F12 44H47F6-
9
11 ꢀ CH2Cl2
55H60Cl2-
FeN2P2Ru2S4 Fe2N3:50P4Ru2S2 N2PRu
13 ꢀ 3.5CH3CN
C109H96:50BCl-
14
Empirical formula
C39H33ClFe-
P2Ru
755.96
C
C
C65H56BFeN-
P2Ru
1080.78
C
-
C
C47H44F6Fe-
P4Ru
1003.62
C
C16H24ClF6-
NOP2RuS
836.67
OP2Ru2S4
1321.34
C2=c
Monoclinic
33.812(4)
10.7494(11)
16.8236(18)
90
FeN1:50P4Ru
1169.21
P2=c
Monoclinic
19.402(7)
10.967(4)
23.112(8)
90
FeO0:50P4Ru
978.62
Formula weight
Space group
Crystal system
1268.12
ꢁ
2003. 50
ꢁ
525.86
P21
Monoclinic
7.5406(4)
10.8604(6)
12.4754(7)
90
P21=c
P21=c
P1
Pbca P21=n
Orthorhombic Monoclinic
P1
Triclinic
P1
Monoclinic
13.5991(7)
14.1731(7)
16.1793(8)
90
Monoclinc
10.9200(7)
22.5250(16)
15.0620(11)
90
Triclinic
11.3484(5)
13.8966(6)
16.7462(7)
80.0980(10)
82.6470(10)
84.5570(10)
2573.03(19)
2
Triclinic
14.5687(12)
17.4655(15)
20.9156(18)
86.325(2)
72.933(2)
73.770(2)
4883.9(7)
2
ꢀ
a (A)
20.0967(12)
16.3787(9)
27.1174(16)
90
13.5735(18)
21.673(3)
14.791(2)
90
10.3688(7)
15.8105(11)
18.1584(12)
101.1610(10)
102.8270(10)
106.1020(10)
2683.2(3)
2
ꢀ
b (A)
ꢀ
c (A)
a (°)
b (°)
c (°)
95.348(2)
90
91.239(2)
90
105.383(2)
90
104.957(9)
90
90
90
96.706(3)
90
96.9350(10)
90
3
ꢀ
V (A )
3104.8(3)
4
1.617
3704.0(4)
4
1.500
5895.7(11)
4
1.489
4751(3)
4
1.635
8925.9(9)
8
1.456
4321.3(10)
4
1.543
1014.18(10)
2
1.722
Z
Dcalc (g cmꢁ3
)
1.395
0.681
1.570
1.176
1.362
0.779
l (mmꢁ1
)
1.172
0.04 ꢂ 0.14
ꢂ 0.20
0.978
0.21 ꢂ 0.21
ꢂ 0.42
0.988
0.30 ꢂ 0.10
ꢂ 0.08
0.843
0.18 ꢂ 0.18
ꢂ 0.09
0.863
0.893
0.24 ꢂ 0.18
ꢂ 0.04
1.040
0.40 ꢂ 0.40
ꢂ 0.26
Crystal size
(mm)
0.4 ꢂ 0.2
ꢂ 0.2
0.1ꢂ 0.04
ꢂ 0.04
1.81–25.00
0.36 ꢂ 0.14
ꢂ 0.08
0.2 ꢂ 0.15
ꢂ 0.05
h Range for data
collection (°)
Data/restraints/
parameters
1.0–30.0
1.6–30.0
1.99–25.00
1.49–30.04
1.82–25.00
1.78–30.07
1.20–25.00
1.52–25.00
1.64–27.50
8838/0/397
1.00
10 762/0/433
1.08
5183/0/347
1.088
14 590/0/641
0.998
8359/825/611
0.828
7855/91/506
1.055
12 128/0/534
1.042
9459/0/617
1.058
17 215/15/1095
1.122
2421/0/178
1.073
Goodness-of-fit
on F 2
Final R indices
R1 ¼ 0:069;
xR2 ¼ 0:120
R1 ¼ 0:049;
xR2 ¼ 0:130
R1 ¼ 0:0482;
R1 ¼ 0:0401;
R1 ¼ 0:0633;
R1 ¼ 0:0594;
R1 ¼ 0:0505;
R1 ¼ 0:0490;
R1 ¼ 0:0916;
R1 ¼ 0:0307;
xR2 ¼ 0:0817
½I > 2rðIÞꢃ
xR2 ¼ 0:1134 xR2 ¼ 0:0816 xR2 ¼ 0:1355 xR2 ¼ 0:1269 xR2 ¼ 0:0899 xR2 ¼ 0:1130 xR2 ¼ 0:1840
a
ꢀ
Temperature for analyses ¼ 223 K; wavelength for analysis ¼ 0.71073 A.

X.L. Lu et al. / Journal of Organometallic Chemistry 689 (2004) 1978–1990
1989
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G.B. Robertson, T.W. Turney, W.A. Wickramasinghe, Organo-
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Diffraction-quality single crystals of 1 were obtained
from CH2Cl2 layered with hexane, 2 ꢀ acetone from ac-
etone layered with ether and 5 ꢀ H2O from a CHCl3 so-
lution layered with hexane after 1–5 days at ambient
temperature, 6, 7, 13 and 14 from CH3CN solutions
layered with ether after 3 days at )29 °C, 8 and 9 from a
solution in MeOH and ether after 3 h at 0 °C and 11
from a solution in CH2Cl2 and hexane after 1 h at 0 °C.
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may be obtained free of charge from The Director,
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