Synthesis and characterisation of [(η6-cymene)Ru(L)X 2] compounds: Single crystal X-ray structure of [(η6- cymene)Ru(P{OPh}3)Cl2] at 203 K

Article abstract of DOI:10.1016/j.poly.2004.06.016

Treatment of the chloro bridged dimer {[(η⁶-cymene)RuCl] ₂(μ-Cl)₂} (1) with the donor molecules in hot hexane causes bridge splitting reactions that produce the monomeric compounds [(η⁶-cymene)Ru(L)Cl₂]. Treatment of the chloro bridged dimer {[(η⁶-cymene)RuCl]₂(μ-Cl)₂} (1) with the donor molecules P(OPh)₃, P(OMe)₃, PPh ₃, PMe₃, CO, SMe₂, CN^tBu and CNTos in hot hexane causes bridge splitting reactions that produce the monomeric compounds [(η⁶-cymene)Ru(L)Cl₂], (4)-(11), respectively. Use of the chiral isonitrile S(-)-α-methylbenzylisonitrile produced the corresponding complex 12. The diiodo analogues, 13-15, were prepared similarly from {[(η⁶-cymene)RuI]₂(μ-I) ₂} (3) for P(OPh)₃, P(OMe)₃ and PPh ₃, respectively. Insertion of tin(II) chloride into both metal-chlorine bonds was observed for [(η⁶-cymene)Ru(P{OMe} ₃)Cl₂] (5), while only monosubstitution was observed for [(η⁶-cymene)Ru(PPh₃)Cl₂] (6). Halide abstraction in the presence of a substrate reaction has been used to prepare some selected cationic compounds which contain an asymmetric ligand environment. Reaction of {[(η⁶-cymene)RuCl]₂(μ-Cl)₂} with 1,2-bis(diphenylphosphino)-ethane under ionising conditions produced the cation [(η⁶-cymene)Ru(dppe)Cl]PF₆ (20). Selected compounds have been examined by {¹³C-¹H} heteronuclear correlation and {¹H-¹H} COSY and NOESY experiments. The structure of [(η⁶-cymene)Ru(P{OPh}₃)Cl₂] ? CH₂Cl₂ (4) has been determined at -70°C.

Full text of DOI:10.1016/j.poly.2004.06.016

Polyhedron 23 (2004) 2695–2707
www.elsevier.com/locate/poly
Synthesis and characterisation of [(g6-cymene)Ru(L)X2] compounds:
single crystal X-ray structure of
[(g6-cymene)Ru(P{OPh}3)Cl2] at 203 K
*
Emma Hodson, Stephen J. Simpson
Department of Chemistry and Applied Chemistry, University of Salford, Cockcroft Building, Salford M5 4WT, UK
Received 16 April 2004; accepted 11 June 2004
Available online 6 August 2004
Dedicated to Malcolm Green on his retirement; thank you for teaching me that chemistry should be fun and that the ‘‘suck it and see’’ approach is
the most fun of all
Abstract
Treatment of the chloro bridged dimer {[(g6-cymene)RuCl]2(l-Cl)2} (1) with the donor molecules P(OPh)3, P(OMe)3, PPh3,
PMe3, CO, SMe2, CNtBu and CNTos in hot hexane causes bridge splitting reactions that produce the monomeric compounds
[(g6-cymene)Ru(L)Cl2], (4)–(11), respectively. Use of the chiral isonitrile S(ꢀ)-a-methylbenzylisonitrile produced the corresponding
complex 12. The diiodo analogues, 13–15, were prepared similarly from {[(g6-cymene)RuI]2(l-I)2} (3) for P(OPh)3, P(OMe)3 and
PPh3, respectively. Insertion of tin(II) chloride into both metal–chlorine bonds was observed for [(g6-cymene)Ru(P{OMe}3)Cl2]
(5), while only monosubstitution was observed for [(g6-cymene)Ru(PPh3)Cl2] (6). Halide abstraction in the presence of a substrate
reaction has been used to prepare some selected cationic compounds which contain an asymmetric ligand environment. Reaction of
{[(g6-cymene)RuCl]2(l-Cl)2} with 1,2-bis(diphenylphosphino)-ethane under ionising conditions produced the cation [(g6-cym-
ene)Ru(dppe)Cl]PF6 (20). Selected compounds have been examined by {13C–1H} heteronuclear correlation and {1H–1H} COSY
and NOESY experiments. The structure of [(g6-cymene)Ru(P{OPh}3)Cl2]ÆCH2Cl2 (4) has been determined at ꢀ70 ꢀC.
ꢁ 2004 Elsevier Ltd. All rights reserved.
Keywords: Cymene; Ruthenium; X-ray
1. Introduction
arene. However the diene precursor to (g6-cymene)ru-
thenium compounds, (R)-a-Phellandrene, (5-isopropyl-
2-methyl-1,3-cyclo-hexadiene) is commercially available
and thus the bulk of the reported chemistry to date is of
complexes of this arene ligand [1,2]. Other arene ligands
such as mesitylene and hexamethylbenzene have gener-
ally been introduced by high temperature ligand ex-
change using the cymene dimer 1 and the free arene.
We have a developing interest in metal complexes
which contain chiral at metal centres and/or chiral lig-
ands. The present work describes the development of
reaction chemistry designed to generate racemic (g6-
cymene)ruthenium complexes with an asymmetric lig-
and environment. These complexes have been examined
The chemistry of (g6-arene)ruthenium half-sandwich
systems has been explored to a lesser extent than that of
the isoelectronic (g5-cyclopentadienyl)ruthenium sys-
tems. This is probably due to the requirement for 1,3-
or 1,4-cyclohexadienes as ligand precursors; these are
normally obtained by Birch reduction of the appropriate
*
Corresponding author. Tel.: +44-161-295-5978; fax: +44-161-295-
5111.
E-mail address: s.j.simpson@salford.ac.uk (S.J. Simpson).
0277-5387/$ - see front matter ꢁ 2004 Elsevier Ltd. All rights reserved.
doi:10.1016/j.poly.2004.06.016

2696
E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
by NMR spectroscopy in order to investigate the chem-
ical shift differentiation of the arene ring substituents.
Some of the compounds prepared have been reported
previously; 4 and 6 [3–5], 5 and 7 [6], and 10 and 11 [7].
We have improved yields in some cases and provided
fuller spectroscopic data in all these cases.
free ligand stretching frequencies being 2143, 2131 and
2150 cmꢀ1, respectively.
The diiodo complexes 12, 13 and 14 were prepared
similarly from {[(g6-cymene)RuI]2(l-I)2} (3) and the lig-
ands in hot heptane solution (see Scheme 2). Treatment
of the red dichloro complex 6 with an excess of sodium
iodide in moist acetone also produced the purple diiodo
complex 14 in 80% yield.
2. Results and discussion
Reaction of anhydrous stannous chloride with 5 in
tetrahydrofuran under reflux led to insertion into both
ruthenium–chlorine bonds producing orange [(g6-cym-
ene)Ru(P{OMe}3)(SnCl3)2)] (15). The poor solubility
of this compound required long acquisition times to ob-
tain NMR spectra and did not allow observation of tin
satellites in the 31P{1H} spectrum. The ring protons on
the cymene ligand of these complexes formally consti-
tute an AA0BB0 spin system, but in all of the complexes
4–15 and the dimer starting materials 1–3 they appear as
the more simple [AB]2 spin system with JAB being
approximately 6 Hz. This is an expected result of both
Treatment of
a
suspension of red {[(g6-cym-
ene)RuCl]2(l-Cl)2} (1) in hexane with triphenylphos-
phite, trimethylphosphite, triphenylphosphine or
trimethylphosphine under reflux for several hours gave
orange or red-orange suspensions of the monomeric
compounds [(g6-cymene)Ru(L)Cl2], (4) to (7), respec-
tively. The salmon-pink carbonyl compound 8 was pre-
pared from the dimer starting material by stirring the
hexane suspension under carbon monoxide (150 psig)
for 2 h at 50 ꢀC. An increase in the reaction time to
12 h resulted in the isolation of a small quantity of
bright yellow crystals which contained two sharp infra-
red absorptions at 2080 and 2023 cmꢀ1. This is probably
[(g6-cymene)Ru(CO)2Cl]Cl and was not investigated
further. Similarly reactions with dimethylsulfide
(SMe2), tert-butylisonitrile (CNtBu) and p-toluenesulfo-
nylmethylisonitrile (CNTos), gave the hexane insoluble
compounds 9 to 11, respectively (see Scheme 1).
Subsequent crystallisation of the precipitated prod-
ucts in each case from dichloromethane/petroleum ether
provided crystalline products which were used for spect-
roscopic characterisation. The infrared spectra of 8, 10
and 11 contain inter alia sharp absorptions at 2042
(mCO), 2133 (mCN) and 2162 cmꢀ1 (mCN), indicating only
a small degree of p-backbonding from the metal centre
to the ligand p* orbitals in the isonitrile complexes; the
5
a very small value of JHH and rapid ring rotation
relative to the [MX2L] fragment; adoption of a static
structure like that found in the solid state for [(g6-cym-
ene)Ru(P{OPh}3)Cl2] (4) (vide infra) must lead to two
isolated [AB] spin systems. The ring substituent chemi-
cal shifts are collected in Table 1, and they do not sug-
gest any correlation with ligand (L) donor or acceptor
properties. The ring proton chemical shift differentiation
(Dd) is largest for compounds 4, 11 and 14, zero for
complex 7, and similar to that of the dimer precursor
for the other complexes. The nature of the three ligands
is such that the ring protons are differentiated in all rota-
tional conformations but it is likely that there may be
some shielding process involving the ring current from
a spatially close pendant phenyl ring. A complete assign-
ment of the cymene ring protons in 6 and 12 was made
possible by obtaining both COSY and NOESY spectra
and demonstrates that the protons ortho to the isopropyl
substituent (H2,6,) are to low-field of those ortho to the
methyl substituent (H3.5). The assignments made in
Table 1 assume that this is generally the case for these
compounds.
Me
CH(Me)2
Me
CH(Me)2
Ru
Ru
Heteronuclear correlation spectra (13C–1H) were ob-
tained for selected compounds to establish if there was
a pattern which would facilitate assignment of the cym-
ene ring chemical shifts for future compounds. Table 2 is
a compilation of these data. It is clear from the values of
D(d13C) that the relative assignment of 13C NMR chem-
ical shifts for the ring methine groups is not predictable;
in the free p-cymene ligand the chemical shifts are d
126.3 and d 129.0 for C2,6 and C3,5, respectively, while
Cl
Cl
L , hexane,
Cl
∆
Ru
Cl
Cl
L
Cl
Me
CH(Me)2
(4) P(OPh)3
(5) P(OMe)3
(6) PPh3
(1)
(7) PMe3
(8) CO
1
the H NMR chemical shifts are isochronous at d 7.32
[8].
(9) SMe2
(10) CNtBu
Replacement of one of the two chloro ligands in the
symmetrical compounds 4 to 11 would produce com-
pounds which contain an asymmetric centre rendering
(11) CNTos
Scheme 1.

E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
2697
Me
CH(Me)2
Me
CH(Me)2
Ru
I
L , heptane,
I
I
∆
Ru
I
L
Ru
I
I
Me
CH(Me)2
(12) P(OPh)3
(13) P(OMe)3
(14) PPh3
(3)
Me
CH(Me)2
Me
CH(Me)2
∆
SnCl2 , THF
Ru
Ru
P(OMe)3
P(OMe)3
Cl
Cl3Sn
Cl3Sn
Cl
(15)
(5)
Me
CH(Me)2
Me
CH(Me)2
∆
SnCl2 , THF
Ru
Ru
PPh3
PPh3
Cl
Cl
Cl3Sn
Cl
(6)
(16)
Scheme 2.
1
all the cymene ring protons inequivalent and also differ-
entiating the isopropyl methyl groups. Such a product
would be obtained as a racemic mixture under most
reaction conditions and in the Schemes 3–5 only one
enantiomer is drawn for clarity.
(see Scheme 2), whose H NMR spectrum contained an
[AB] system (dA 6.11, dB 6.01) and two doublets (d 5.29,
4.95) for the cymene ring protons. The isopropyl group
methyl resonances occur as two doublets at d 1.21, 1.14.
The nature of the three ligands is such that the ring pro-
tons are differentiated in all rotational conformations
but it is likely that the major conformation is one which
has a pair of protons in a similar environment and the
other pair more strongly differentiated, such as in Fig. 1.
In contrast to 15, the greater solubility of 16 allowed
the observation of the tin satellites in the 31P{1H} NMR
A valuable synthetic target would be to prepare neu-
tral molecules of the type [(g6-cymene)Ru(L)(Cl)X]
where X is a different halogen; differing metal–halogen
bond strengths in subsequent reactions could be
exploited. All efforts to replace one chloro ligand with a
bromo, cyano or iodo ligand using sodium or potassium
salts failed, variation of stoichiometry, solvent, reaction
time and temperature gave only mixtures of the symmet-
rical product, starting material and trace amounts of the
required product. Later work with analogues containing
more heavily substituted arene ligands has proved more
successful [9]. Reaction of [(g6-cymene)Ru(PPh3)Cl2]
(6) with stannous chloride in tetrahydrofuran gave the or-
ange complex [(g6-cymene)Ru(PPh3)(SnCl3)(Cl)] (16)
spectrum; the values of J(119Sn–31P) and J(117Sn–31P)
being 704 and 671 Hz, respectively.
2
2
Treatment of the dimer 1 with the chiral isonitrile lig-
and S(ꢀ)-a-methylbenzylisonitrile under the conditions
used for compounds 10 and 11 gave red microcrystalline
17 (see Scheme 3). The cymene ring protons are all dif-
ferentiated in the H NMR spectrum of 17 as expected
when a chiral centre is introduced. The remoteness of
1

2698
E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
Table 1
1H NMR chemical shifts for the compounds {[(g6-cymene)RuX]2(l-X)2} (1)–(3) and [(g6-cymene)Ru(L)X2] (4)–(15)
L
X
H2,6
H3,5
Dd
Me
CHMe2
CHMe2
Cl
Br
I
1
2
3
4
5
6
7
8
9a
5.44
5.63
5.51
5.39
5.52
5.17
5.39
5.94
5.61
5.53
5.72
5.32
5.56
5.42
6.18
5.30
5.48
5.41
5.07
5.38
4.97
5.39
5.79
5.43
5.37
5.40
5.17
5.38
4.90
6.02
0.14
0.15
0.10
0.32
0.14
0.20
0.00
0.15
0.18
0.16
0.32
0.15
0.18
0.52
0.16
2.12
2.25
2.33
1.80
2.15
1.84
2.02
2.35
2.18
2.26
2.30
2.11
2.39
1.94
2.47
1.24
1.28
1.22
1.16
1.22
1.07
1.18
1.30
1.31
1.27
1.29
1.13
1.23
1.06
1.30
2.90
2.78
2.98
2.70
2.90
2.83
2.81
2.87
2.92
2.80
2.92
3.07
3.22
3.42
2.99
P(OPh)3
P(OMe)3
PPh3
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
I
PMe3
CO
SMe2
CNtBu
CNTos
P(OPh)3
P(OMe)3
PPh3
10
11
12
13
14
15b
I
I
SnCl3
P(OMe)3
Other compounds in CDCl3.
a
(CD3)2CO.
CD2Cl2.
b
Table 2
13C–1H correlation data for selected compounds in CDCl3
H2,6
H3,5
C2,6
C3,5
D(d13C)
{[(g6-cymene)RuCl]2(l-Cl)2}
{[(g6-cymene)RuBrl]2(l-Br)2}
{[(g6-cymene)RuI]2(l-I)2}
1
2
5.44
5.63
5.51
5.39
5.32
5.52
5.56
5.17
5.42
5.30
5.48
5.41
5.07
5.17
5.38
5.38
4.97
4.90
81.20
78.54
82.02
88.60
87.85
88.80
89.31
87.20
88.70
80.50
78.68
82.51
88.90
90.33
89.10
89.31
89.00
88.60
0.70
ꢀ0.14
ꢀ0.49
ꢀ0.30
ꢀ2.48
ꢀ0.30
0.00
3
[(g6-cymene)Ru(P{OPh}3)(Cl)2]
[(g6-cymene)Ru(P{OPh}3)(I)2]
[(g6-cymene)Ru(P{OMe}3)(Cl)2]
[(g6-cymene)Ru(P{OMe}3)(I)2]
[(g6-cymene)Ru(PPh3)(Cl)2]
[(g6-cymene)Ru(PPh3)(I)2]
4
12
5
13
6
ꢀ1.80
0.10
14
Me
CH(Me)2
Me
CH(Me)2
Ru
Ru
Cl
Cl
Cl
Ru
Cl
Cl
H
Cl
N
Ph
Me
CH(Me)2
Me
(17)
(1)
Scheme 3.
the chiral centre from the cymene ring protons induces
an equivalence of only 0.02 ppm between the position-
ally related pairs. The heteronuclear correlation spec-
trum (13C–1H) established the ((dH, dC) pairings (5.56,
87.9), (5.54, 87.5), (5.40, 87.6) and (5.38, 87.4) establish-
ing the effect of the remote chiral centre on the cymene
ring carbon atoms.
Halide abstraction in the presence of a substrate can
also be used to generate asymmetric metal centres; thus
the reaction of 4 with dimethylsulfoxide in hot methanol

E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
2699
Me
CH(Me)2
Me
CH(Me)2
L , NH4PF6
Ru
Ru
Methanol ,
Cl
Cl
Cl
Ph3P
Ph3P
L
L = SMe2
(20)
(21)
CNBu
CNTos (22)
quinoline (23)
Scheme 4.
Ru
Ru
S
S
Ph3P
Ph3P
MeB
MeA
Cl
Cl
MeA
MeB
inversion
rotation
MeB
MeA
Ru
S
Ph3P
Cl
Scheme 5. Rotation–inversion process for the SMe2 group in 20.
solutions containing ammonium hexafluorophosphate
produced bright yellow [(g6-cymene)Ru(P{OPh}3)
(S{O}Me2)(Cl)]PF6 (18).
Similarly compound 5 could be transformed into the
cation [(g6-cymene)Ru(P{OMe}3)(S{O}Me2)(Cl)]PF6
(19). The infrared spectra of 18 and 19 contained a weak
band at 1124 and 1129 cmꢀ1, respectively, indicative of
sulfur rather than oxygen coordination. Treatment of 6
with dimethylsulfide, tert-butylisonitrile, p-toluenesulfo-
nylmethylisonitrile, or quinoline gave the requisite cati-
onic compounds 20 to 23, respectively, (see Scheme 4).
The partial 1H NMR chemical shift data for compounds
18 to 23 showing the cymene ring and isopropyl ligand
methyl group resonances are collected in Table 3. The
assignment of the ring protons is given such that HA
and HB are mutually coupled and HC and HD form
the other coupled pair. It seems reasonable to conclude
that HA and HC are the H2,6 pair while HB and HD are
the H3,5 ring protons. The appearance of ‘‘AB-roofing’’
Cl
Cl
PPh3
SnCl3
Cl3Sn
Ph3P
Fig. 1. Possible preferred conformations of 16.

2700
E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
Table 3
1H NMR chemical shifts for [(g6-cymene)Ru(L)(Lꢀ)Cl]PF6 (18)–(23)
L
L0
HA
HB
HC
HD
Me
Me0
P(OPh)3
P(OMe)3
PPh3
S(O)Me2
S(O)Me2
SMe2
18
6.23
6.53
5.93
6.09
6.13
6.01
6.23
6.45
5.89
4.95
4.77
5.97
5.78
6.51
5.45
5.78
6.08
5.52
5.01
6.27
4.96
5.59
5.95
5.33
1.25
1.31
1.29
1.30
1.27
1.06
1.12
1.30
1.28
1.24
1.22
1.03
19a
20
PPh3
PPh3
PPh3
CNtBu
21
CNTos
quinoline
22b
23b
Other compounds are recorded in deuterodichloromethane.
a
Recorded in deuteroacetone.
Recorded in deuterochloroform.
b
Table 4
˚
Selected bond lengths (A) and bond angles (ꢀ) for 4
Ru(1)–C(1)
Ru(1)–C(3)
Ru(1)–C(5)
Ru(1)–Cl(1)
Ru(1)–P(1)
P(1)–O(2)
2.199(3)
2.246(3)
2.202(3)
2.4022(8)
2.2642(8)
1.607(2)
Ru(1)–C(2)
Ru(1)–C(4)
Ru(1)–C(6)
Ru(1)–Cl(2)
P(1)–O(1)
2.241(3)
2.222(3)
2.177(3)
2.3992(8)
1.596(2)
1.584(2)
P(1)–O(3)
Cl(1)–Ru(1)–Cl(2)
Cl(1)–Ru(1)–P(1)
Cl(2)–Ru(1)–P(1)
87.45(3)
87.91(2)
85.01(3)
O (1)–P(1)–O(2)
O (1)–P(1)–O(3)
O (2)–P(1)–O(3)
104.74(11)
98.70(10)
102.06(11)
1
in the 300 MHz H NMR spectra of these compounds
has been used to aid this assignment.
ligand. The ruthenium–phosphorus bond Ru(1)–P(1) bi-
sects one edge of the cymene ligand, C(5)–C(6), the
arrangement expected for minimization of intramolecu-
lar repulsions. Selected bond lengths and angles are gi-
ven in Table 4. The general structure is similar to that
These compounds all show inequivalence of the dia-
stereotopic methyl groups of the isopropyl fragment
and of the four ring protons. The relative shieldings
for some particular complexes, such as 21 and 22, indi-
cate some preferred conformations leading to differen-
tial proximity shielding arising from the p-system of
the isonitrile group. The dimethylsulfide group of com-
pound 20 exhibited a broad singlet resonance (d 2.40)
at 294 K which changed into the expected pair of sin-
glets on cooling (d 2.49, 2.22); the barrier (DG245) to this
rotation-inversion process was 49.1 kJ molꢀ1 at coales-
cence (see Scheme 5).
In compounds 18 and 19 where this exchange process
is not possible the methyl groups of the dimethylsulfox-
ide ligands were anisochronous (d 3.55, 3.37) and (d
3.55, 3.27), respectively, as required by the lack of
molecular mirror planes.
The reaction of the dimer 1 with bis-1,2-(diph-
enylphosphino)ethane (dppe) and ammonium hexa-
fluorophosphate in 1,2-dichloroethane under reflux
produced
the
symmetrical
cation
[(g6-cym-
ene)Ru(dppe)(Cl)]PF6 (24). The conductivity of a dilute
nitromethane solution (ca. 5 mM) of this salt was 57.3
Xꢀ1 cm2 molꢀ1 while that of the very weakly ionized 8
and 9 was 2.0 and 1.3 Xꢀ1 cm2 molꢀ1, respectively.
The X-ray single crystal structure of 4 was deter-
mined at 203K in order to confirm the disposition of
the three metal r-bound ligands relative to the cymene
Fig. 2. Structure of the ruthenium containing fragment in 4 showing
25% probability ellipsoids.

E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
2701
found for other [(g6-cymene)Ru(L)(Cl)2] compounds,
for example L = PCy3 [10], L = P(m-tolyl)3 [10] and
at Butterworth Laboratories, London and Manchester
University laboratories. Fast Atom Bombardment
(FAB) mass spectra were obtained on a Kratos Con-
cept S1 spectrometer. R(ꢀ)-a-Phellandrene (technical
grade) was used as received from Fluka. Tert-butyliso-
nitrile and S(ꢀ)-a-methylbenzylisonitrile were pre-
pared from the respective amines by the phase-
transfer Hofmann carbylamine reaction. Compounds
2 and 3 were prepared from 1 by a literature proce-
dure [13].
t
L = PPh2 Bu [11].
Fig. 2 shows the structure obtained of the ruthenium
containing fragment and omits the dichloromethane sol-
vent molecule which is also present in the unit cell. The
1
solution structure of 4, as evidenced by the H NMR
spectrum, shows that there is free rotation of the cymene
ligand about the ruthenium centre and this is consistent
with the general disposition of the phenyl rings in the tri-
phenylphosphite ligand.
4.1. Preparation of {[(g6-cymene)RuCl]2(l-Cl)2} (1)
3. Conclusions
Hydrated ruthenium trichloride (0.74g, 2.83 mmol) in
ethanol (40 ml) was heated under reflux overnight with
a-phellandrene (2 ml, 16.4 mmol). The orange precipi-
tate was filtered off, washed with methanol and dried un-
der reduced pressure, yield 0.55 g, 63.5%. 1H NMR
[CDCl3]: da 5.44, db 5.30 (dd, J(HH) ꢁ 6.0 Hz, 4H,
C2,3,5,6-H{ring}), 2.90 (sept, J(HH) ꢁ 7 Hz, H,
CH(Me)2), 2.12 (s, 3H, CH3{ring}), 1.24 (d,
J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2); 13C{1H} NMR
[CDCl3]: d 101.1 (s, C1(quat)), 96.7 (s, C4(quat)), 81.2 (s,
C2,6-H{ring}), 80.5 (s, C3,5-H{ring}), 30.6 (s,
CH(Me)2), 22.1 (s, CH(Me)2), 18.9 (s, Me{ring}).
The methine protons of the cymene ligand in these
complexes are a sensitive reporter of the auxiliary ligand
1
environment in H NMR spectroscopy. Even the pres-
ence of a very remote chiral centre in the complex 17 dif-
ferentiates these ring protons. There does not appear to
be a straightforward predictive method of absolutely
assigning d(C2,6) and d(C3,5) in the 13C NMR spectra
of these complexes, the relative ordering being variable
unlike the ordering in their 1H NMR spectra. We will re-
port subsequently our results with related compounds
possessing planar chiral arene ligands where the asym-
metry of the arene ligand facilitates absolute assignment,
and also our results concerning the absence of a barrier
to rotation of the cymene ring in the compounds [(g6-
cymene)Ru(L)Cl2] in the range 170–350 K [12].
4.2. Preparation of [(g6-cymene)Ru(P{OPh}3)Cl2] (4)
A mixture of 1 (0.30 g, 0.49 mmol) and triphenyl-
phosphite (1 ml) in hexane (30 ml) was heated under re-
flux for 8 h. The reaction mixture yielded a red
microcrystalline solid which was filtered warm. The
product was washed with light petroleum ether (2 · 10
ml). The crude product was crystallised from dichloro-
methane and light petroleum ether to give bright red
4. Experimental
All reactions and preparations were carried out on
a vacuum/nitrogen line using standard Schlenk-tube
techniques. Diethylether was dried over sodium wire.
Dichloromethane, hexane, heptane, petroleum ether
(40–60 ꢀC) and Analar grade acetone were used as
supplied. All solvents were degassed prior to use. All
products isolated were dried under reduced pressure,
in a hot water bath for at least one hour. Infrared
spectra were recorded on a Perkin–Elmer 1710 FTIR
instrument, calibrated against polystyrene film; only
significant absorption bands are reported. Nuclear
magnetic resonance spectra were recorded on Bruker
AC300 (300.13 MHz, 1H; 75.47 MHz, 13C; 121.49
1
crystals, yield 0.38 g, 62%. H NMR [CDCl3]: d 7.22
(m, 15H, Ph3), da 5.39, db 5.07 (dd, J(HH) ꢁ 6.0 Hz,
4H, C2,3,5,6-H{ring}), 2.70 (sept, J(HH) ꢁ 7.0 Hz, H,
CH(Me)2), 1.8 (s, 3H, CH3{ring}), 1.16 (d,
J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2)); 13C{1H}NMR
[CDCl3]:
d
151.44 (d, J(PC) ꢁ 11.0 Hz, Cipso
,
,
P{OPh}3), 129.42 (s, Cortho, P{OPh}3), 125.06 (s, Cpara
P{OPh}3), 121.74 (d, J(PC) ꢁ 4.0 Hz, Cmeta, P{OPh}3)
109.37 (s, C1(quat)), 103.07 (s, C4(quat)), 88.92 (d,
J(PC) ꢁ 7.0 Hz, C3,5-H{ring}), 88.60 (d, J(PC) ꢁ 6.0
Hz, C2,6-H{ring}), 30.55 (s, CH(Me)2), 22.11 (s,
CH(Me)2), 17.96 (s, Me{ring}); 31P{1H} NMR [CDCl3]:
d 104.2 (s, P{OPh}3).
MHz 31P) and Bruker Avance 400 (400.13 MHz, H;
1
100.62 MHz, 13C; 161.98 MHz 31P) spectrometers.
All 1H and 13C NMR chemical shifts are expressed
in ppm relative to SiMe4 (0.00 ppm) and 31P NMR
chemical shifts relative to P(OPh)3 (126.5 ppm). All
NMR and infrared spectra were measured at room
temperature. Standard Bruker microprograms were
used for the acquisition of HETCORR, NOESY and
COSY-45 spectra. Elemental analyses were obtained
4.3. Preparation of [(g6-cymene)Ru(P{OMe}3)Cl2] (5)
A suspension of 1 (0.1 g, 0.16 mmol) and trimethyl-
phosphite (0.1 ml) in hexane (30 ml) was heated under
reflux for 4 h. After solvent removal under reduced pres-

2702
E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
sure, fine orange crystals were obtained by crystallising
the orange residue at ꢀ30 ꢀC from dichloromethane
and light petroleum ether overnight, yield 0.14 g,
99.6%. Calc. for C13H23Cl2O3PRu: C, 36.27; H, 5.34.
Found: C, 36.24; H, 5.19%. IR (nujol): mmax 1042 s,
4.6. Preparation of [(g6-cymene)Ru(CO)Cl2] (8)
A suspension of 1 (0.18 g, 0.29 mmol) in hexane
(30ml) was pressurised with carbon monoxide (150
psig.) in a Fischer–Porter bottle and stirred at 50 ꢀC
for 2 h. Evaporation of the solvent under reduced pres-
sure produced a salmon pink solid, which upon crystal-
lisation from dichloromethane and petroleum ether
afforded bright red microcrystals, yield 0.12 g, 56.0%.
Calc. for C11H14Cl2ORu: C, 39.51; H, 4.19. Found: C,
38.34; H, 4.06%. IR (nujol): mmax 2042 s, cmꢀ1 (CO);
1H NMR [CDCl3]: da 5.94, db 5.79 (dd, J(HH) ꢁ 6.5
Hz, 4H, C2,3,5,6-H{ring}), 2.87 (sept, J(HH) ꢁ 7.0
Hz, H, CH(Me)2), 2.35 (s, 3H, CH3{ring}), 1.30 (d,
J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2); 13C{1H} NMR
[CDCl3]: d 189.7 (s, CO), 114.8 (s, C1(quat)), 113.5 (s,
C4(quat)), 93.4 (s, C2,6-H{ring}), 93.0 (s, C3,5-H{ring}),
31.4 (s, CH(Me)2), 22.5 (s, CH(Me)2) 19.1 (s, Me{ring}).
1
839 w cm-1 (PO). H NMR [CDCl3]: da 5.52, db 5.38
(dd, J(HH) ꢁ 6.0 Hz, 4H, C2,3,5,6-H{ring}), 3.77 (d,
J(PH) ꢁ 10.8 Hz, 9H, P{OMe}3), 2.90 (sept,
J(HH) ꢁ 7.0 Hz, H, CH(Me)2), 2.15 (s, 3H, CH3{ring}),
1.22 (d, J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2); 13C{1H}
NMR [CDCl3]: d 109.9 (s, C1(quat)), 101.9 (s, C4(quat)),
89.1 (d, J(PC) ꢁ 6.0 Hz, C2,6-H{ring}), 88.8 (d,
J(PC) ꢁ 6.0 Hz, C3,5-H{ring}), 54.3 (d, J(PC) ꢁ 6.0
Hz, P(OMe)3), 30.4 (s, CH(Me)2), 22.0 (s, CH(Me)2)
18.3 (s, Me{ring}); 31P{1H} NMR [CDCl3]: d 115.9 (s,
P{OMe}3). M.S.[FAB]: m/z 432 {M+}.
4.4. Preparation of [(g6-cymene)Ru(PPh3)Cl2] (6)
4.7. Preparation of [(g6-cymene)Ru(SMe2)Cl2] (9)
A suspension of 1 (0.4 g, 0.32 mmol) and triphenyl-
phosphine (0.4 g, 1.52 mmol) in hexane (30 ml) was
heated under reflux for 5 h. After solvent removal under
reduced pressure, bright red crystals were obtained by
crystallising the red residue at ꢀ30 ꢀC from dichloro-
methane and light petroleum ether overnight, yield
A suspension of 1 (0.2 g, 0.33 mmol) and dimethylsul-
fide (0.3 ml) in hexane (30 ml) was heated under reflux in
an oil bath overnight. The solvent was removed under
reduced pressure. Dissolution in dichloromethane (30
ml), and slow addition of light petroleum ether yielded
bright red crystals on storage at ꢀ30 ꢀC overnight, yield
0.18 g, 74.8%. Calc. for C12H20Cl2SRu: C, 39.12; H,
5.43. Found: C, 39.09; H, 5.45%. 1H NMR [(CD3)2
CO]: da 5.61, db 5.43 (dd, J(HH) ꢁ 6.0 Hz, 4H,
C2,3,5,6-H{ring}), 2.92 (sept, J(HH) ꢁ 7.0 Hz, H,
CH(Me)2), 2.29 (s, 6H, SMe2), 2.18 (s, 3H, CH3{ring}),
1.31 (d, J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2); 13C{1H}
NMR [(CD3)2 CO]: d 104.6 (s, C1(quat)), 99.4 (s,
C4(quat)), 84.2 (s, C2,6-H{ring}), 83.8 (s, C3,5-H{ring}),
31.4 (s, CH(Me)2), 22.6 (s, SMe2), 22.3 (s, CH(Me)2),
1
0.59 g, 80%. H NMR [CDCl3]: d 7.84ꢀ7.24 (m, 15H,
PPh3), da 5.17, db 4.97 (2d, 4H, J(HH) ꢁ 6.0 Hz, C-
H{ring}), 2.83 (sept, H, J(HH) ꢁ 7.0 Hz, CH(Me)2),
1.84 (s, 3H, CH3{ring}), 1.07 (d, 6H, J(HH) ꢁ 7.0 Hz,
CH(Me)2); 13C{1H} NMR [CDCl3]:
d 134.3 (d,
J(PC) ꢁ 10.0 Hz, Cortho, PPh3), 128.0 (s, Cpara, PPh3),
128.0 (d, J(PC) ꢁ 10.0 Hz, Cmeta, PPh3), 111.2 (s,
C1(quat)), 96.0 (s, C4(quat)), 89.0 (s, C2,6-H{ring}), 87.2
(s, C3,5-H{ring}), 30.2 (s, CH(Me)2), 21.9 (s, CH(Me)2),
17.7 (s, Me{ring}); 31P{1H} NMR [CDCl3]: d 23.1 (s,
PPh3). M.S.[FAB]: m/z 568 {M+}.
18.3
(s,
Me{ring}).
M.S.[FAB]:
m/z
577
{C20H28Cl3Ruþ2 }, 368 {M+}.
4.5. Preparation of [(g6-cymene)Ru(PMe3)Cl2] (7)
4.8. Preparation of [(g6-cymene)Ru(CNtBu)Cl2] (10)
A suspension of 1 (0.2 g, 0.32 mmol) and trimethyl-
phosphine (0.15 ml) in hexane (30 ml) was heated under
reflux for 4 h. After solvent removal under reduced pres-
sure, fine orange crystals were obtained by crystallising
the orange residue at ꢀ30 ꢀC from dichloromethane
and light petroleum ether overnight, yield 0.22 g, 88%.
1H NMR [CDCl3]: d 5.39 (d, 4H, J(HH) ꢁ 6.0 Hz, C-
H{ring}), 2.81 (sept, H, J(HH) ꢁ 7.0 Hz, CH(Me)2),
2.02 (s, 3H, CH3{ring}), 1.57 (d, 9H, J(PH) ꢁ 11.0 Hz,
PMe3), 1.18 (d, 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2);
13C{1H} NMR [CDCl3]: d 106.8 (s, C1(quat)), 93.4 (s,
C4(quat)), 89.2 (d, J(PC) ꢁ 3.5 Hz, C-H{ring}), 84.7 (d,
J(PC) ꢁ 5.5 Hz, C-H{ring}), 30.5 (s, CH(Me)2), 21.9
(s, CH(Me)2), 18.2 (s, Me{ring}), 16.3 (d, J(PC) ꢁ 33.5
Hz, PMe3); 31P{1H} NMR [CDCl3]: d 3.08 (s, PMe3).
M.S.[FAB]: m/z 382 {M+}.
Tert-butylisonitrile (0.2 ml) was added to a suspen-
sion of 1 (0.15 g, 0.25 mmol) in hexane (30 ml) and
heated under reflux in an oil bath overnight. Filtration
and evaporation under reduced pressure produced an
orange residue. Dissolution in dichloromethane and
slow addition of light petroleum ether afforded a bright
orange microcrystalline solid 10, yield 0.12 g, 61.5%.
Calc. for C15H23Cl2NRu: C, 46.26; H, 5.91. Found: C,
45.95; H, 5.91%. IR (nujol): mmax 2194 s, cmꢀ1 (CN).
1H NMR [CDCl3]: da 5.53, db 5.37 (dd, J(HH) ꢁ 6.0
Hz, 4H, C2,3,5,6-H{ring}), 2.80 (sept, J(HH) ꢁ 7.0
Hz, H, CH(Me)2), 2.26 (s, 3H, CH3{ring}), 1.58 (s,
CNC(CH3)3), 1.27 (d, J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2);
13C{1H} NMR [CDCl3]: d 137.0 (s, CNC(CH3)3), 107.6
(s, C1(quat)), 106.3 (s, C4(quat)), 87.4 (s, C2,6-H{ring}),

E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
2703
87.2 (s, C3,5-H{ring}), 58.5 (s, CNC(CH3)3), 31.3 (s,
CH(Me)2), 30.6 (s, CNC(CH3)3), 22.5 (s, CH(Me)2),
18.7 (s, Me{ring}).
4.11. Preparation of [(g6-cymene)Ru(P{OMe}3)I2]
(13)
A suspension of 3 (0.2 g, 0.32 mmol) and trimethyl-
phosphite (0.2 ml) in heptane (30 ml) was heated under
reflux for 5 h. Dissolution into dichloromethane, filtra-
tion, concentration and slow addition of light petroleum
ether yielded deep red/purple crystals on storage at ꢀ30
ꢀC, overnight, yield 0.21 g, 80%. Calc. for C13H23O3-
PI2Ru: C, 25.41; H, 3.75. Found: C, 25.24; H, 3.69%).
1H NMR [CDCl3]: da 5.56 db 5.38 (2d, 2H,
J(HH) ꢁ 6.0 Hz, C-H{ring}), 3.73 (d, 9H,
J(PH) ꢁ 11.0 Hz, P{OMe}3), 3.22 (sept, H,
J(HH) ꢁ 7.0 Hz, CH(Me)2), 2.39, (s, 3H, CH3{ring}),
1.23 (d, 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2); 13C{1H}
NMR [CDCl3]: d 113.31 (d, J(PC) ꢁ 5.0 Hz, C1(quat)),
103.38 (d, J(PC) ꢁ 3.0 Hz, C4(quat)), 89.31 (d,
J(PC) ꢁ 4.0 Hz, C2,6-H{ring}), 89.31 (d, J(PC) ꢁ 4.0
Hz, C3,5-H{ring}), 55.30 (d, J(PC) ꢁ 7.0 Hz,
P(OMe)3), 31.55 (s, CH(Me)2), 22.56 (s, CH(Me)2)
20.06 (s, Me{ring}); 31P{1H} NMR [CDCl3]: d 118.7
(s, P{OMe}3). M.S.[FAB]: m/z 613 {M+}.
4.9. Preparation of [(g6-cymene)Ru(CNCH2SO2-
C6H4Me)Cl2] (11)
A mixture of 1 (0.15 g, 0.25 mmol) and p-toluene-
sulfonylmethylisocyanide (0.18 g, 0.92 mmol) was sus-
pended in hexane and heated under reflux for 12 h.
The product was filtered, washed with petroleum ether
and dried under reduced pressure. Dissolution in dichlo-
romethane followed by slow addition of light petroleum
ether afforded an orange microcrystalline solid, charac-
terised as 11, yield 0.15 g, 61.1%. Calc. for
C19H23O2Cl2NSRu: C, 45.50; H, 4.59. Found: C,
43.84; H, 4.61%. IR (nujol): mmax 2162 s, cmꢀ1 (CN).
1H NMR [CDCl3]: da 7.87, db 7.41 (dd, J(HH) ꢁ 8.0
Hz, 4H, Me(C6H4)SO2CH2CN), da 5.72, db 5.40 (dd,
J(HH) ꢁ 5.5 Hz, 4H, C2,3,5,6-H{ring}), 4.96 (s, 2H,
Me(C6H4)SO2CH2CN), 2.92 (sept, J(HH) ꢁ 7.0 Hz, H,
CH(Me)2), 2.43 (s, 3H, Me(C6H4)SO2CH2CN), 2.30 (s,
3H, Me{ring}), 1.29 (d, J(HH) ꢁ 7.0 Hz, 6H,
CH(Me)2)). 13C{1H} NMR [CDCl3]: d 147.1 (s, C(quat)
,
4.12. Preparation of [(g6-cymene)Ru(PPh3)I2] (14)
Me(C6H4)SO2CH2CN), 132.5 (s, C(quat), Me(C6H4)-
SO2CH2CN), 130.8 (s, Me(C6H4)SO2CH2CN), 129.1
(s, Me(C6H4)SO2CH2CN), 109.9 (s, C1(quat)), 108.5 (s,
C4(quat)), 89.5 (s, C2,6-H{ring}), 89.4 (s, C3,5-H{ring}),
63.6 (s, Me(C6H4)SO2CH2CN), 31.2 (s, CH(Me)2), 22.4
(s, CH(Me)2) 21.8 (s, Me(C6H4)SO2CH2CN) 18.9 (s,
Me{ring}). M.S.[FAB]: m/z 501 {M+}.
An acetone solution of 6 (0.22 g) and a large excess of
NaI (0.5 g, 3.34 mmol) was heated to 50 ꢀC for 4 h. The
solvent was removed under reduced pressure. Dissolu-
tion into dichloromethane, filtration, concentration
and slow addition of light petroleum ether yielded deep
red/purple crystals on storage at ꢀ30 ꢀC, overnight,
yield 0.20 g, 80%. Calc. for C28H29PI2Ru: C, 44.68; H,
4.10. Preparation of [(g6-cymene)Ru(P{OPh}3)I2]
(12)
3.89. Found: C, 44.78; H, 4.09%. H NMR [CDCl3]: d
1
7.77ꢀ7.34 (m, 15H, PPh3), da 5.42, db 4.90 (2d, 4H,
J(HH) ꢁ 6.0 Hz, C-H{ring}), 3.42 (sept, H,
J(HH) ꢁ 7.0 Hz, CH(Me)2), 1.94 (s, 3H, CH3{ring}),
1.06 (d, 3H, J(HH) ꢁ 7.0 Hz, CH(Me)2); 13C{1H}
A mixture of 3 (0.30 g, 0.49 mmol) and triphenyl-
phosphite (1 ml) in heptane (30 ml) was heated under re-
flux for 6 h. The reaction mixture yielded a purple
microcrystalline solid which was filtered warm. The
product was washed with light petroleum ether (2 · 10
ml). The crude product was crystallised from dichloro-
methane and light petroleum ether to give light purple
crystals, yield 0.6 g, 85%. Calc. for C28H29O3PI2Ru: C,
NMR [CDCl3]: d 135.6 (d, J(PC) ꢁ 47.0 Hz, Cipso
,
PPh3), 135.0 (d, J(PC) ꢁ 8.5 Hz, Cortho, PPh3), 130.2
(s, Cpara, PPh3), 127.6 (d, J(PC) ꢁ 9.5 Hz, Cmeta
,
PPh3), 112.71 (br.s, C1(quat)), 99.5 (s, C4(quat)), 88.7,
88.6 (2s, C-H{ring}), 32.0 (s, CH(Me)2), 18.9 (s,
CH(Me)2), 18.1 (s, Me{ring}); 31P{1H} NMR [CDCl3]:
d 21.4 (s, PPh3).
1
42.00; H, 3.63. Found: C, 41.88; H, 3.85%. H NMR
[CDCl3]: d 7.41 (m, 15H, Ph3), da 5.32, db 5.17 (dd,
J(HH) ꢁ 6.0 Hz, 4H, C2,3,5,6-H{ring}), 3.07 (sept,
J(HH) ꢁ 7.0 Hz, H, CH(Me)2), 2.11 (s, 3H, CH3{ring}),
1.13 (d, J(HH) ꢁ 7.0 Hz, 6H, CH(Me)2)); 13C{1H}
4.13. Preparation of [(g6-cymene)Ru(P{OMe}3)
(SnCl3)2] (15)
NMR [CDCl3]: d 152.03 (d, J(PC) ꢁ 12.0 Hz, Cipso
,
,
Prior to use SnCl2 Æ2H2O was dehydrated by stirring
vigorously in acetic anhydride (120 g salt for 100 g anhy-
dride) for 1 h. The salt was filtered, washed with dry
ether (2 · 50 ml) and dried under reduced pressure.
Dehydrated stannous chloride (0.07 g, 0.39 mmol) was
then added to a solution of 5 (0.1 g, 0.23 mmol) in
THF and heated under refluxing conditions for 4 h. A
yellow precipitate formed, concentration and filtration
P{OPh}3), 129.48 (s, Cortho, P{OPh}3), 125.00 (s, Cpara
P{OPh}3), 121.86 (d, J(PC) ꢁ 4.0 Hz, Cmeta, P{OPh}3)
114.17 (s, C1(quat)), 102.84 (s, C4(quat)), 87.85 (d,
J(PC) ꢁ 7.0 Hz, C2,6-H{ring}), 90.33 (d, J(PC) ꢁ 6.0
Hz, C3,5-H{ring}), 31.69 (s, CH(Me)2), 22.49 (s,
CH(Me)2), 19.93 (s, Me{ring}); 31P{1H} NMR [CDCl3]:
d 105.7 (s, P{OPh}3).

2704
E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
gave 12 as a yellow solid. Evaporation of the filtrate
gave a small amount of a crystalline yellow-orange solid
identified as 15 by 1H NMR spectroscopy. Yield 0.12 g,
65%. Calc. for C13H23PO3Cl6Sn2Ru: C, 19.27; H, 2.84.
Found: C, 20.08; H, 3.20%. 1H NMR [CD2Cl2]: da
6.18 db 6.02 (2d, 4H, J(HH) ꢁ 6.5 Hz, C-H{ring}),
3.83 (d, 9H, J(PH) ꢁ 12.0 Hz, P{OMe}3), 2.99 (sept,
H, J(HH) ꢁ 7.0 Hz, CH(Me)2), 2.47 (d, 3H,
J(PH) ꢁ 1.5 Hz, CH3{ring}), 1.30 (d, 6H, J(HH) ꢁ 7.0
Hz, CH(Me)2); 13C{1H} NMR [CD2Cl2]: d 121.0 (s,
C1(quat)), 113.8 (br.s, C4(quat)), 92.0, 91.8, (2s, C-
H{ring}), 56.0 (d, J(PC) ꢁ 9.5 Hz, P{OMe}3), 31.6 (s,
CH(Me)2), 23.2 (s, CH(Me)2), 20.0 (s, Me{ring});
31P{1H} NMR [CD2Cl2]: d 127.8 (s, PMe3). M.S.[FAB]:
m/z 773 {M+}.
Ph), da 5.56, db 5.54 (dd, 2H, J(HH) ꢁ 6.0 Hz, C-
H{ring}), da 5.40, db 5.38 (2d, 2H, J(HH) ꢁ 6.0 Hz,
C-H{ring}), 5.18 (q, H, J(HH) ꢁ 7.0 Hz, CHMeNC),
2.72 (sept, J(HH) ꢁ 7.0 Hz, H, CH(Me)2), 2.22 (s, 3H,
CH3{ring}), 1.72 (d, 3H, J(HH) ꢁ 7.0 Hz, CHMeNC),
1.19, 1.18 (2d, 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2);
13C{1H} NMR [CD2Cl2]: d 140.9 (ꢀtꢀ, J(NC) ꢁ 15.0
Hz, CHMeNC), 137.9 (s, Cipso, Ph), 129.0 (s, Cortho
,
Ph), 128.5 (s, Cpara, Ph), 125.5 (s, Cmeta, Ph), 107.4 (s,
C1(quat)), 106.9 (s, C4(quat)), 87.9, 87.6, 87.5, 87.4 (4s,
C-H{ring}), 53.8 (s, CHMeNC), 31.1 (s, CH(Me)2),
24.8 (s, CHMeNC), 22.3, 22.2 (2s, CH(Me)2), 18.7 (s,
Me{ring}). M.S.[FAB]: m/z 437 {M+}.
4.16. Preparation of [(g6-cymene)Ru(P{OPh}3)-
(SOMe2)Cl]PF6 (18)
4.14. Preparation of [(g6-cymene)Ru(PPh3)Cl(SnCl3)]
(16)
Dimethylsulfoxide (1 ml) was added to a solution of 4
(0.15 g, 0.24 mmol) and ammonium hexafluorophos-
phate (0.2 g, 1.22 mmol) in methanol (30 ml) and stirred
at 50 ꢀC for 6 h. The solution turned progressively paler.
The solvent was removed under reduced pressure to give
a bright orange oil. A mixture of dichloromethane (20
ml) and water (5 ml) was added and shaken, the dichlo-
romethane layer was separated and dried with calcium
chloride. Filtration and addition of diethylether afforded
bright yellow microcrystals, identified as 18. Yield 0.10
g, 50%. Calc. for C30H35ClF6O4P2SRu: C, 41.59; H,
4.04. Found: C, 41.90; H, 4.12%. IR (nujol): mmax
Freshly dehydrated stannous chloride (0.03 g, 0.16
mmol) was added to a solution of 6 (0.1 g, 0.12 mmol)
in dry THF (30 ml) and heated under refluxing condi-
tions for 4 h. The solution changed from red to orange.
Removal of the solvent under reduced pressure pro-
duced an orange solid, which was crystallised from
dichloromethane and diethylether. Yield 0.10 g, 71%.
Calc. for C28H29PCl4SnRu: C, 44.34; H, 3.83. Found:
1
C, 44.38; H, 3.74%). H NMR [CD2Cl2]: d 7.71ꢀ7.32
(m, 15H, Ph), da 6.11 db 6.01 (2d, 2H, J(HH) ꢁ 6.0
Hz, C-H{ring}), 5.29 (d, H, J(HH) ꢁ 6.0 Hz, C-
H{ring}), 4.95 (d, H, J(HH) ꢁ 6.0 Hz, C-H{ring}),
2.45 (sept, H, J(HH) ꢁ 7.0 Hz, CH(Me)2), 1.84 (s, 3H,
CH3{ring}), 1.21, 1.14 (2d, 6H, J(HH) ꢁ 7.0 Hz,
1
1124, 1054 br, 845 s (PF6ꢀ) cmꢀ1. H NMR [CD2Cl2]:
d 7.40ꢀ6.89 (m, 15H, Ph), 6.23 (d, 2H, J(HH) ꢁ 6.5
Hz, C-H{ring}), 5.78, 5.01 (2d, Hc, Hd, J(HH) ꢁ 6.5
Hz, C-H{ring}), 3.55, 3.37 (2s, 6H, SOMe2), 2.65 (sept,
J(HH) ꢁ 7.0 Hz, H, CH(Me)2), 2.07 (s, 3H, CH3{ring}),
1.25, 1.12 (2d, 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2); 13C{1H}
CH(Me)2); 13C{1H} NMR [CD2Cl2]: d 134.9 (s, Cipso
,
PPh3), 134.2 (d, J(PC) ꢁ 9.5 Hz, Cortho, PPh3), 131.3
(s, Cpara, PPh3), 129.0 (d, J(PC) ꢁ 10.0 Hz, Cmeta
,
NMR [CD2Cl2]: d 151.0 (d, J(PC) ꢁ 14.0 Hz, Cipso
,
,
PPh3), 116.5 (s, C1(quat)), 102.8 (s, C4(quat)), 92.3, 90.9,
89.3 (3s, C-H{ring}), 89.0 (d, J(PC) ꢁ 5.0 Hz, C-
H{ring}), 30.5 (s, CH(Me)2), 22.6, 22.4 (2s,
CH(Me)(Me0)), 18.1 (s, Me{ring}); 31P{1H} NMR
[CD2Cl2]: d 27.7 (s, Sn satellites, 2J(119Sn–31P) ꢁ 704
Hz, 2J(117Sn–31P) ꢁ 671 Hz, PPh3). M.S.[FAB]: m/z
534 {M+}.
P{OPh}3), 130.7 (s, Cortho, P{OPh}3), 126.9 (s, Cpara
P{OPh}3), 121.4 (d, J(PC) ꢁ 3.0 Hz, Cmeta, P{OPh}3),
126.1 (s, C1(quat)), 108.7 (s, C4(quat)), 98.9 (s, C-H{ring}),
97.6 (d, J(PC) ꢁ 5.0 Hz, C-H{ring}), 93.8 (d,
J(PC) ꢁ 10.0 Hz, C-H{ring}), 89.8 (s, C-H{ring}),
51.6, 51.2 (2s, SOMe2) 31.7 (s, CH(Me)2), 21.7, 21.6
(2s, CH(Me)2), 18.4 (s, Me{ring}); 31P{1H} NMR
[CD2Cl2]: d 109.0 (s, P{OPh}3). M.S.[FAB]: m/z 721
{M+}.
4.15. Preparation of [(g6-cymene)Ru(CN-(S)-CH(Me)
(Ph))Cl2] (17)
4.17. Preparation of [(g6-cymene)Ru(P{OMe}3)-
(SOMe2)Cl]PF6 (19)
S(ꢀ)-a-Methylbenzylisonitrile (0.2 ml) was added to
a suspension of 1 (0.15 g, 0.49 mmol) in hexane and
heated at 70 ꢀC for 12 h. Filtration and evaporation un-
der reduced pressure produced a red residue. Crystallisa-
tion from dichloromethane and petroleum ether (40–60
ꢀC) afforded microcystalline 17. Yield 0.19 g, 89%. Calc.
for C19H23NCl2Ru: C, 52.17; H, 5.26; N, 3.20. Found:
C, 52.36; H, 5.46; N, 3.05%. IR (nujol): mmax 2186
NH4PF6 (80 mg, 0.49 mmol) was added to a solu-
tion of complex 5 (0.15 g, 0.35 mmol) and dimethyl-
sulfoxide (0.2 ml) in methanol (30 ml) and stirred at
room temperature for 48 h. The solvent was removed
under reduced pressure and the orange residue ex-
tracted with dichloromethane. Concentration and slow
addition of diethylether afforded bright yellow crystals
1
(CN) cmꢀ1. H NMR [CD2Cl2]: d 7.40–7.24 (m, 5H,

E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
2705
on storage in a refrigerator (ꢀ30 ꢀC, overnight), yield
1.78%. IR (nujol): mmax 2180 (CN), 840 s (PF6) cmꢀ1
.
0.14 g, 64%. Calc. for C15H29ClF6O4P2SRu: C, 29.15;
H, 4.70. Found: C, 28.71; H, 4.80%). IR (nujol): mmax
1H NMR [CD2Cl2]: d 7.59ꢀ7.46 (m, 15H, Ph), da
6.09, db 5.78 (2d, 2H, J(HH) ꢁ 6.5 Hz, C-H{ring}),
5.59, 4.95 (2d, Hc, Hd, J(HH) ꢁ 6.5 Hz, C-H{ring}),
2.78 (sept, H, J(HH) ꢁ 7.0 Hz, CH(Me)2), 1.96 (s, 3H,
CH3{ring}), 1.33, 1.24 (2d, 6H, J(HH) ꢁ 7.0 Hz,
CH(Me)2), 1.23 (s, 9H, CNC(Me)3); 13C{1H} NMR
1
1129, 1064 br (SO), 839 s (PF6ꢀ) cmꢀ1. H NMR [ac-
etone-d6]: da 6.53, db 6.45, da 6.51, db 6.27 (4d, 4H, C-
H{ring}), 4.02 (d, 9H, J(PC) ꢁ 11.0 Hz, P{OMe}3),
3.56, 3.27 (2s, 6H, SOMe2), 2.89 (sept, H,
J(HH) ꢁ 7.0 Hz, CH(Me)2), 2.26 (s, 3H, CH3{ring}),
1.31, 1.30 (2d, 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2);
13C{1H} NMR [acetone-d6]: d 123.2 (s, C1(quat)),
109.2 (s, C4(quat)), 98.2, 97.0, 96.9, 91.9 (4s, C-
H{ring}), 55.8 (d, J(PC) ꢁ 8.5 Hz, P{OMe}3), 31.8 (s,
CH(Me)2), 21.9, 21.6 (2s, CH(Me)2), 18.4 (s, Me{r-
[CD2Cl2]:
d
156.6 (s, CNC(Me)3), 134.2 (d,
J(PC) ꢁ 10.0 Hz, Cortho, PPh3), 132.0 (s, Cpara, PPh3),
131.6 (d, J(PC) ꢁ 51.5 Hz, Cipso, PPh3), 129.3 (d,
J(PC) ꢁ 10.5 Hz, Cmeta, PPh3), 118.7 (d, J(PC) ꢁ 5.5
Hz, C1(quat)), 113.6 (s, C4(quat)), 99.3 (d, J(PC) ꢁ 5.0
Hz, C-H{ring}), 98.2, 94.5, 91.9 (3s, C-H{ring}), 60.1
(s, CNC(Me)3), 32.2 (s, CH(Me)2), 29.9 (s, CNC(Me)3),
23.7, 21.6 (2s, CH((Me)2), 18.9 (s, Me{ring}); 31P{1H}
NMR [CD2Cl2]: d 36.1 (s, PPh3). M.S.[FAB]: m/z 616
{M+}.
ing}); 31P{1H} NMR [acetone-d6]:
P{OMe}3). M.S.[FAB]: m/z 473 {M+}.
d
119.8 (s,
4.18. Preparation of [(g6-cymene)Ru(PPh3)(SMe2)Cl]
(20)
4.20.
CNCH2SO2C6H4Me)Cl]PF6 (22)
Preparation
of
[(g6-cymene)Ru(PPh3)(p-
Dimethylsulfide (1 ml) was added to a solution of 6
(0.3 g, 0.53 mmol) and ammonium hexafluorophos-
phate (0.2 g, 1.22 mmol) in methanol (30 ml) and stirred
at 50 ꢀC for 6 h. The solvent was removed under re-
duced pressure to give a yellow oily solid. Crystallisa-
tion from dichloromethane and diethylether gave
yellow/orange fluffy microcrystals of 20 yield 0.29 g,
74%. Calc. for C30H35ClF6P2SRu: C, 48.68; H, 4.47.
Found: C, 49.01; H, 4.84%. IR (nujol): mmax 841 s
p-Toluenesulfonylmethylisocyanide, NH4PF6 (0.1 g,
0.61 mmol) and 6 (0.1 g, 0.18 mmol) were dissolved in
methanol (30 ml) and stirred at room temperature for
3 h. The solution turned bright yellow after 10 min.
Evaporation of the solvent and crystallisation from
dichloromethane and diethylether afforded yellow
microcrystalline 22. Yield 0.11 g, 73%. Calc. for
C37H38ClF6NO2P2SRu: C, 52.07; H, 5.00; N, 1.84.
Found: C, 50.91; H, 4.39; N, 1.59%. IR (nujol): mmax
1
(PF6) cmꢀ1. H NMR [CD2Cl2]: d 7.58ꢀ7.44 (m, 15H,
Ph), da 5.93, db 5.89 (2d, 2H, J(HH) ꢁ 7.0 Hz, C-
H{ring}), 5.45 (d, H, J(HH) ꢁ 6.5 Hz, C-H{ring}),
4.96 (dd, H, J(HH) ꢁ 6.5 Hz, J(PH) ꢁ 3.0 Hz, C-
H{ring}), 2.82 (sept, H, J(HH) ꢁ 7.0 Hz, CH(Me)2),
2.40 (s, 6H, SMe2) 1.67 (s, 3H, CH3{ring}), 1.29, 1.28
(2d 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2); 13C{1H} NMR
[CD2Cl2]: d 134.6 (d, J(PC) ꢁ 9.5 Hz, Cortho, PPh3),
1
2185 (CN), 842 s (PF6) cmꢀ1. H NMR [CDCl3]: da
7.77 (d, J(AB) ꢁ 8.0 Hz, 4H, Me(C6H4)SO2CH2CN),
7.48ꢀ7.31 (m, 17H, Me(C6H4)SO2CH2CN + PPh3),
6.13 (dd, H, J(HH) ꢁ 6.5 Hz, J(PH) ꢁ 1.0 Hz, C-
H{ring}), da 6.08, db 5.95 (2d, 2H, J(AB) ꢁ 6.5 Hz,
C-H{ring}), 5.09 (d, H, J(HH) ꢁ 15.5 Hz, Me(C6H4)-
SO2CH2CN), 4.77 (d, H, J(HH) ꢁ 6.5 Hz, C-H{ring}),
4.03 (dd, H, J(HH) ꢁ 15.5 Hz, J(PH) ꢁ 2.0 Hz,
Me(C6H4)SO2CH2CN), 2.93 (sept, H, J(HH) ꢁ 7.0 Hz,
CH(Me)2), 2.44 (s, 3H, Me(C6H4)SO2CH2CN), 1.80
(d, 3H, J(PH) ꢁ 1.0 Hz, CH3{ring}), 1.27 (d, 3H,
J(HH) ꢁ 7.0 Hz, CH(Me)(Me0)), 1.22 (d, 3H,
J(HH) ꢁ 7.0 Hz, CH(Me)(Me0)); 13C{1H} NMR
[CDCl3]: d 150.0 (d, J(PC) ꢁ 29.0 Hz, Me(C6H4)-
SO2CH2CN), 146.5, 132.7 (2s, C(quat), Me(C6H4)-
SO2CH2CN), 133.9 (d, J(PC) ꢁ 10.0 Hz, Cortho, PPh3),
131.6 (s, Cpara, PPh3), 130.4 (s, Me(C6H4)SO2CH2CN),
130.2 (d, J(PC) ꢁ 53.0 Hz, Cipso, PPh3), 129.5 (s,
Me(C6H4)SO2CH2CN), 128.8 (d, J(PC) ꢁ 10.5 Hz, Cme-
ta, PPh3), 121.3 (d, J(PC) ꢁ 5.0 Hz, C1(quat)), 115.6 (s,
C4(quat)), 1 01.9 (d, J(PC) ꢁ 5.0 Hz, C-H{ring}), 98.0,
93.7, 92.2 (3s, C-H{ring}), 63.1 (s, Me(C6H4)
SO2CH2CN), 31.6 (s, CH(Me)2), 23.5 (s, CH(Me)
(Me0)), 21.8 (s, Me(C6H4)SO2CH2CN), 21.4 (s,
CH(Me)(Me0)), 18.6 (s, Me{ring}); 31P{1H} NMR
[CDCl3]: d 38.1 (s, PPh3). M.S.[FAB]: m/z 728 {M+}.
131.8 (s, Cpara, PPh3), 131.3 (d, J(PC) ꢁ 49.0 Hz, Cipso
,
PPh3), 129.0 (d, J(PC) ꢁ 10.5 Hz, Cmeta, PPh3), 122.1
(br.s, C1(quat)), 101.5 (s, C4(quat)), 93.0 (s, C-H{ring}),
91.0 (s, C-H{ring}), 89.5 (d, J(PC) ꢁ 7.5 Hz, C-
H{ring}), 87.4 (s, C-H{ring}), 31.3 (s, CH(Me)2), 26.3
(s, SMe2), 22.1, 21.6 (2s, CH(Me)2), 17.9 (s, Me{ring});
31P{1H} NMR [CD2Cl2]: d 29.7 (s, PPh3). M.S.[FAB]:
m/z 595 {M+}.
4.19. Preparation of [(g6-cymene)Ru(PPh3) (CNtBu)-
Cl]PF6 (21)
Tert-butylisonitrile (0.5 ml), NH4PF6 (0.1 g, 0.61
mmol) and 6 (0.1 g, 0.18 mmol) were dissolved in meth-
anol (30 ml) and stirred at room temperature for 3 h.
The solution turned pale yellow after 10 min. Evapora-
tion of the solvent and crystallisation from dichlorome-
thane and diethylether afforded yellow microcrystalline
21, yield 0.12 g, 75%. Calc. for C33H38ClF6NP2Ru: C,
52.07; H, 5.00; N, 1.84. Found: C, 52.74; H, 4.91; N,

2706
E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
4.21. Preparation of [(g6-cymene)Ru(PPh3)(C9H7N)-
Cl]PF6 (23)
4.23. X-ray structure of (4)
Well-shaped red cubes were obtained by crystallisa-
tion from a dichloromethane/diethylether mixture on
cooling to ꢀ30 ꢀC. A suitable crystal specimen was
mounted on a glass fibre with epoxy resin and cooled
on the goniometer head by means of nitrogen gas to
203 K. Precession photographs and intensity data were
collected on a Siemens R3m/V diffractometer using
graphite monochromatised Mo Ka X-rays.
A red solution of 6 (0.10 g, 0.18 mmol) and KPF6 in
methanol (30 ml) was treated with quinoline (1 ml) and
stirred at room temperature for 24 h. A bright yellow so-
lid precipitated out on concentration. The solution was
filtered and the yellow solid washed with diethylether.
Crystallisation from dichloromethane and diethylether
afforded microcrystalline 23. Yield 0.09 g, 62%. Calc.
for C37H36ClF6NP2Ru: C, 55.05; H, 4.46; N, 1.74; re-
calc. for 0.5 mol CH2Cl2: C, 53.00; H, 4.36; N, 1.65.
Found: C, 53.58; H, 4.44; N, 1.63%. IR (nujol): mmax
Crystal data. C28H29Cl2O3PRuÆCH2Cl2, M = 701.4,
monoclinic, space group P21/n, a = 12.936(2),
˚
A,
b = 16.809(3),
U = 3009.6(8) A , Dc = 1.548
c = 13.979(2)
b = 98.06(1)ꢀ,
3
837 s (PF6) cmꢀ1
.
1H NMR [CDCl3]: d 9.41 (s, H,
g
cmꢀ3 for Z = 4,
˚
C9H7N), 8.67 (d, H, J(HH) ꢁ 6.5 Hz, C9H7N),
7.87ꢀ7.47 (m, 22H, Ph, C9H7N), 6.01, 5.97, 5.52, 5.33
(4d, 4H, J(HH) ꢁ 6.0 Hz, C-H{ring}), 2.17 (sept, H,
J(HH) ꢁ 7.0 Hz, CH(Me)2), 1.65 (s, 3H, CH3{ring}),
1.06, 1.03 (2d, 6H, J(HH) ꢁ 7.0 Hz, CH(Me)2);
13C{1H} NMR [CDCl3]: d 159.4 (s, C9H7N), 147.8 (s,
C9H7N), 134.0 (s, Cortho, PPh3), 133.0 (s, C9H7N),
F(000) = 1424, l(Mo Ka) = 9.59 cmꢀ1, T = -70 ꢀC,
crystal size 0.45 · 0.45 · 0.50 mm3. Cell dimensions were
obtained from 50 centred reflections with 2h values from
22.5ꢀ to 32.1ꢀ. Intensity data in the range
3.5ꢀ < 2h < 58.0ꢀ were collected using a 2hꢀh scan tech-
nique. The intensities of three reflections measured peri-
odically showed a decrease of less than 1% over the data
collection. An empirical absorption correction was ap-
plied using azimuthal scan data for twelve selected
reflections. A total of 8285 reflections were collected of
which 7966 were independent and 6992, for which
I > 2r(I), were used in the refinement. The structure
was solved by standard heavy atom routines and refined
by full matrix least squares methods. All non-hydrogen
atoms were given anisotropic temperature factors.
Hydrogen atoms were placed in the model at calculated
positions and allowed to ride on their respective carbon
atoms. The highest peaks in the final difference map
131.0 (s, Cpara, PPh3), 128.6 (d, J(PC) ꢁ 8.5 Hz, Cmeta
,
PPh3), 128.6, 128.5 (s, C9H7N), 128.2 (s, C9H7N),
126.0 (s, C9H7N), 123.0 (s, C9H7N), 114.1 (d,
J(PC) ꢁ 8.0 Hz, C1(quat)), 103.5 (s, C4(quat)), 94.7 (d,
J(PC) ꢁ 6.0 Hz, C-H{ring}), 90.2, 88.7, 84.0 (3s, C-
H{ring}), 30.8 (s, CH(Me)2), 23.1, 20.9 (2s, CH(Me)2),
18.1 (s, Me{ring}); 31P{1H} NMR [CDCl3]: d 36.6 (s,
PPh3). M.S.[FAB]: m/z 662 {M+}.
4.22. Preparation of [(g6-cymene)Ru(dppe)Cl]PF6 (24)
3
˚
were <1.6 e A , at convergence R1 = 4.55% and
A Schlenk tube was charged with a solution of 1 (0.2
g, 0.33 mmol) in 1,2 dichloroethane (25 ml), NH4PF6
(0.3 g, 1.84 mmol), dppe (0.52 g, 1.31 mmol) and a mag-
netic stirrer bar. The orange solution was stirred under
reflux conditions for 16 h. After solvent removal under
reduced pressure the yellow residue was extracted in
dichloromethane (2 · 15 ml). Concentration followed
by addition of light petroleum ether produced yellow
microcrystals on storage at ꢀ30 ꢀC overnight, yield
0.32 g, 60.2%. H NMR [acetone-d6]: d 7.97–7.36 (m,
20H, Ph) da 6.38, db 6.24 (dd, J(HH) ꢁ 6.0 Hz, 4H,
C2,3,5,6-H{ring}), 3.12-2.92 (m, 4H, PPh2(CH2)2PPh2)
2.24 (sept, J(HH) ꢁ 7 Hz, H,CH(CH3)2), 1.21 (s, 3H,
CH3{ring}), 0.87 (d, J(HH) ꢁ 7 Hz, 6H, CH(CH3)2);
13C{1H} NMR [acetone-d6]: d 136.3 (ꢁtꢀ, J(PC) ꢁ 46.5
Hz, Cipso), 134.7, 133.1 (2s, Cortho, PPh3), 132.2, 131.9
(2s, Cpara, PPh3), 130.0, 129.2 (2ꢁstꢀ, J(PC) ꢁ 10.0 Hz,
wR2 = 12.73%, w = [r2 (Fo) + 0.0822P2 + 2.0235P]ꢀ1
2
where P = (Fo2 + 2Fo )/3, S = 1.10 for a data/parameter
ratio 20.4:1.
5. Supplementary material
CCDC-236210 contains the supplementary crystallo-
graphic data for this paper. These data can be obtained
free of charge via ccdc.cam.ac.uk/data_request/cif, by
emailing data_request@ccdc.cam.ac.uk, or by contact-
ing The Cambridge Crystallographic Data Centre, 12
Union Road, Cambridge, CB2 1EZ, UK; fax +44
1223 336033.
C
meta, PPh3), 123.5 (s, C1(quat)), 101.3 (s, C4(quat)), 96.2
Acknowledgements
(s, C2,6-H{ring}), 92.3 (s, C3,5-H{ring}), 31.1 (s,
CH(Me)2), 26.8 (t, J(PC) ꢁ 22 Hz, PPh2(CH2)2PPh2)
21.4 (s, CH(Me)2) 15.8 (s, Me{ring}). 31P{1H} NMR
[acetone-d6]: d 72.7 (s, PPh2(CH2)2PPh2), 144.1 (sept,
PF6ꢀ). M.S.[FAB]: m/z 669 {M+}.
We thank the S.E.R.C. for a studentship (E.H.),
Johnson–Matthey Chemicals Ltd., for a generous loan
of RuCl3, and we acknowledge the use of the EPSRCꢀs
Chemical Database Service at Daresbury [14].

E. Hodson, S.J. Simpson / Polyhedron 23 (2004) 2695–2707
2707
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