Reactivity and X-ray structural studies in ligand substitution of [Cp/(Ind)-Ru(dppf)Cl] - Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl] {Cp = η5-C5H5, Ind = η5-C 7H9, dppf = 1,1′-bis(diphenylphosphanyl)ferrocene, Josiphos = (R)-(-)-1-[(S)-2-(diphenylphosphanyl)ferrocenyl] ethyldicyclohexylphosphane}

Article abstract of DOI:10.1002/ejic.200600726

Ligand substitution of [(Ind)Ru(PPh₃)₂Cl] (1) led to the isolation of [(Ind)Ru(PPh₃)(Ph₂P(CH₂) ₂C₉H₇}Cl] (2), [(Ind)Ru(dppf)Cl] (3) and [(Ind)Ru{(Ph₂PCH₂)₃CMe}]PF₆ ([4]PF₆), and diastereoisomers [(R)- and (S)-(Ind)Ru(Josiphos)Cl] [(R)-5 and (S)-5], where (R)-(S)-Josiphos is the ferrocene-based chiral diphosphane ligand (R)-(-)-1-[(S)-2-(diphenylphosphanyl)ferrocenyl] ethyldicyclohexylphosphane. The Cp analogues of 5, viz. (R)-6 and (S)-6, were also obtained from [CpRu(PPh₃)₂Cl] (1a). Josiphos-dependent epimerisation was observed, with conversion of the (S) isomer to the (R) isomer in both cases. Chloride abstraction of 3 with NaPF ₆ in CH₃CN and NaN₃ in EtOH gave [(Ind)Ru(dppf)(CH₃CN)]PF₆ ([7]PF₆) and [(Ind)Ru(dppf)(N₃)] (8), respectively. The azido ligand in 8 underwent [3+2] dipolar cycloaddition with dimethyl acetylenedicarboxylate to give a N-bound bis-(methoxycarbonyl)-1,2,3-triazolato complex, 9. X-ray crystal structures of the new complexes, except (R)-5, (S)-5 and (S)-6, have been determined. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.

Full text of DOI:10.1002/ejic.200600726

FULL PAPER
DOI: 10.1002/ejic.200600726
Reactivity and X-ray Structural Studies in Ligand Substitution of [Cp/(Ind)-
Ru(dppf)Cl] – Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl] {Cp = η5-C5H5, Ind
= η5-C7H9, dppf = 1,1Ј-Bis(diphenylphosphanyl)ferrocene, Josiphos = (R)-(–)-
1-[(S)-2-(Diphenylphosphanyl)ferrocenyl]ethyldicyclohexylphosphane}
Sin Yee Ng,[a] Guihua Fang,[a] Weng Kee Leong,*[a] Lai Yoong Goh,*[a] and
Marc V. Garland[b]
Keywords: Indenyl / Ruthenium / dppf / Josiphos / Epimerisation / Phosphanes
Ligand substitution of [(Ind)Ru(PPh3)2Cl] (1) led to the isola-
tion of [(Ind)Ru(PPh3){Ph2P(CH2)2C9H7}Cl] (2), [(Ind)Ru-
(dppf)Cl] (3) and [(Ind)Ru{(Ph2PCH2)3CMe}]PF6 ([4]PF6), and
diastereoisomers [(R)- and (S)-(Ind)Ru(Josiphos)Cl] [(R)-5
and (S)-5], where (R)-(S)-Josiphos is the ferrocene-based chi-
ral diphosphane ligand (R)-(–)-1-[(S)-2-(diphenylphos-
phanyl)ferrocenyl] ethyldicyclohexylphosphane. The Cp an-
alogues of 5, viz. (R)-6 and (S)-6, were also obtained from
[CpRu(PPh3)2Cl] (1a). Josiphos-dependent epimerisation was
observed, with conversion of the (S) isomer to the (R) isomer
in both cases. Chloride abstraction of 3 with NaPF6 in
CH3CN and NaN3 in EtOH gave [(Ind)Ru(dppf)(CH3CN)]PF6
([7]PF6) and [(Ind)Ru(dppf)(N3)] (8), respectively. The azido
ligand in 8 underwent [3+2] dipolar cycloaddition with di-
methyl acetylenedicarboxylate to give
a N-bound bis-
(methoxycarbonyl)-1,2,3-triazolato complex, 9. X-ray crystal
structures of the new complexes, except (R)-5, (S)-5 and (S)-
6, have been determined.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2007)
of its Cp analogue, 1a.[7] The enhanced reactivity, com-
monly known as the “indenyl effect”, was found to be
largely brought about by ring slippage.[8] The combined ef-
fect of capping ligand and phosphane ligand variant would
therefore be of interest. We note that research in recent
years on (Ind)Ru chemistry has been focused on vinylidene
and allenylidene complexes by the group of Gimeno,[8,9]
and nitrogen-containing ligands, for example, amines, ni-
triles, N,NЈ-donor Schiff bases and azine ligands, by Kolli-
para and co-workers.[10] In this work, we have investigated
the reactivity of 1 with the ferrocenyl diphosphane ligands
1,1Ј-bis(diphenylphosphanyl)ferrocene (dppf) and chiral
ferrocenyl diphosphane ligand {(R)-(S)-Josiphos} and with
the tripod ligand {(Ph2CH2)3CMe}, and the reactivity of
[(Ind)Ru(dppf)Cl] (3) towards N-containing ligands.
Introduction
The chemistry of phosphane organometallic complexes
has been well established in the last four decades,[1] interest
being fuelled by their roles in medicinal and catalytic appli-
cations.[2] In particular, [CpRu(PPh3)2Cl] (1a), first synthe-
sised in 1969 by Gilbert and Wilkinson,[3] has attracted
much attention. A rich chemistry has unfolded, based on
the facile substitution of the PPh3 ligand by two-electron
donors, as well as the ready displacement of the chlorido
ligand by both anionic and neutral ligands.[4] Its well-de-
fined CpRu(PPh3)2 moiety is an attractive auxiliary that can
be used for the attachment of organic groups in studies of
their steric and electronic effects on the chemical[4a] and
catalytic[5] reactivity of the complex. More recently, the role
of metallophosphane ligands, for example, of the symmetri-
cal and unsymmetrical ferrocenyl type, in catalysis of or-
ganic reactions is increasingly being studied, as the ligands
become more readily available.[6]
Results and Discussion
The marked effect of the capping ligand on reactivity of
the complex came to light with the synthesis of [(Ind)-
Ru(PPh3)2Cl] (1) (Ind = η5-C9H7) some 16 years after that
Phosphane Substitution
Synthesis of [(Ind)Ru(PPh3){Ph2P(CH2)2C9H7}Cl] (2),
[(Ind)Ru(dppf)Cl] (3) and [(Ind)Ru(tripod)]PF6
([4]PF6)
[a] Department of Chemistry, National University of Singapore,
3 Science Drive, Singapore 117543
As in [CpRu(PPh3)2Cl] (1a), the substitution lability of
PPh3 in [(Ind)Ru(PPh3)2Cl] (1) has provided an easy entry
to various [(Ind)Ru] complexes. For instance, [(Ind)Ru-
(diphos)Cl] had been synthesised from a reaction of [(Ind)-
Fax: +65-6779-1691
E-mail: chmgohly@nus.edu.sg
chmlwk@nus.edu.sg
[b] Institute of Chemical and Engineering Sciences,
1 Pesek Road, Jurong Island, Singapore 627833
452
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2007, 452–462

Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl]
FULL PAPER
1
Ru(PPh3)2Cl] by substitution with the desired diphos in re-
The H NMR spectrum of 3 shows an ABCD pattern
fluxing toluene.[7] Adopting the reported procedure for the for the proton signals of the ferrocene rings at δ = 3.66,
synthesis of (Ind)Ru(dppe)Cl [dppe = 1,2-bis(diphenylphos- 3.83, 3.90 and 4.20, suggesting an eclipsed conformation for
phanyl)ethane],[11] phosphane substitution of 1 at elevated the chelating dppf ligand in 3;[12] this was supported by the
temperature in toluene gave air- and moisture-stable red so- X-ray single-crystal diffraction analysis. The Cp proton sig-
lids of the monophosphane-substituted complex [(Ind)- nals of the η5-indenyl ligand appear at δ = 4.66 (H1) and
Ru{Ph2P(CH2)2C9H7}(PPh3)Cl] (2), containing the (1-inde- 5.57 (H2,3). The latter resonance is 1.67 ppm downfield
nylethyl)diphenylphosphane ligand LH (Scheme 1a), the di- shifted from that in the bis(PPh3) analogue, owing to relief
phosphane-substituted complex [(Ind)Ru(dppf)Cl] (3) with from the shielding effect caused by the ring current of the
dppf (Scheme 1b), and a totally substituted complex [(Ind)- Ph ring of PPh3 on H2 and H3 in 1.[13]
1
Ru(Ph2PCH2)3Me]PF6 ([4]PF6) with the tripodal triphos li-
gand (Ph2PCH2)3CMe (Scheme 1c), in high yields.
The H NMR spectrum of [4]PF6 shows a multiplet at δ
≈ 1.5 and a broad singlet at δ ≈ 2.39, assigned to the methyl
It is anticipated that phosphane substitution of 1 will be and methylene groups of the tripod ligand, indicating the
facilitated by the release of steric stress in the coordination fluxionality of these groups in solution. However, a sharp
sphere by dissociation of one or both of the bulky PPh3 singlet at δ = 39.9 in the 31P NMR spectrum indicates an
ligands. This is very likely the driving force in the formation equivalent chemical environment for the three coordinated
of 2, as the ligand LH is less bulky than PPh3. In the cases phosphorus atoms of tripod. The proton resonances of H1
of 3 and [4]PF6, the reactions are additionally assisted by and H2,3 of the indenyl ligand appear at δ = 5.51 and
the chelating effect of the incoming di- and triphosphane 5.57 ppm, while H4–7 appear as two characteristic four-line
ligand, respectively.
multiplets at δ = 7.31–7.34 and δ = 7.43–7.47, respectively.
1
The H NMR spectrum of 2 shows four multiplets in
The molecular structures of 2, 3 and [4]+ have been deter-
the range δ = 1.79–3.52, assigned to the four inequivalent mined by single-crystal X-ray crystallographic studies; their
methylene protons of LH. The CH2 protons of the five- ORTEP diagrams are shown in Figures 1, 2 and 3, respec-
membered ring of LH resonate at δ = 2.93, while the ole- tively, and selected bond parameters are compared with
finic proton resonates at a higher field at δ = 6.5. On the those of CpRu(dppf)Cl[14] in Table 1.
other hand, the protons H1–3 (see Experimental Section for
The molecular structures of 2 and 3 show Ru hexacoor-
numbering scheme) of the η5-coordinated Ind ligand reso- dinated to Ind, a Cl atom and two phosphorus atoms, that
nate at δ = 4.95–5.00 and δ = 5.78 ppm. The 31P NMR is, from PPh3 and C9H7(CH2)2PPh2 in 2 and from chelating
spectrum shows two doublets at δ = 46.5 and δ = 50.0 with dppf in 3. The molecular structure of [4]+ consists of a mo-
–
2JPP = 42.9 Hz due to the coupling of the two inequivalent nonuclear cation [(η5-Ind)Ru(tripod)]+ and PF6 anion, to-
phosphorus atoms.
Scheme 1.
Eur. J. Inorg. Chem. 2007, 452–462
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
453

S. Y. Ng, G. Fang, W. K. Leong, L. Y. Goh, M. V. Garland
FULL PAPER
Figure 1. ORTEP diagram of 2. Thermal ellipsoids are drawn to
50% probability level. Hydrogen atoms are omitted for clarity. Se-
lected bond lengths: C1–C2 1.530(7) Å; C2–C3 1.506(6) Å; C3–C11
1.329(7) Å; C3–C4 1.454(7) Å; C4–C5 1.375(7) Å; C5–C6
1.388(8) Å; C6–C7 1.374(9) Å; C7–C8 1.368(9) Å; C8–C9
1.3859(8) Å; C9–C4 1.401(7) Å; C9–C10 1.513(8) Å; C10–C11
1.494(7) Å. Other bond parameters are given in Table 1.
Figure 2. ORTEP diagram of 3. Thermal ellipsoids are drawn to
50% probability level. Hydrogen atoms are omitted for clarity.
gether with two solvent molecules of dichloromethane, one
of which is disordered.
A general, yet prominent structural feature of η5-indenyl
complexes is the distortion from η5- to η3-coordination,
equivalent to an allyl-ene bonding description for the C5
ring. Such a distortion is found in 2, 3 and [4]+, as evident
from the values of their slip distortions (∆) and hinge angles
(HA), which fall in the range of small or moderate distor-
tion towards a η3 binding mode.[15] The slightly larger dis-
tortion in 3 (longer ∆) is probably a result of the stronger
σ-donor capability of dppf.[8] The unusually large fold angle
(FA) in [4]+ likely arises from the steric congestion created
by the phenyl rings of the tripod ligand, which causes the
benzenoid ring of the indenyl ligand to twist upwards,
Figure 3. ORTEP diagram of [4]+. Thermal ellipsoids are drawn to
50% probability level. Hydrogen atoms are omitted for clarity.
Table 1. Selected bond parameters of complexes 2, 3, [4]+ and [CpRu(dppf)Cl].
Complexes
2
3
[4]+
[CpRu(dppf)Cl][14]
∆ [Å][a]
0.182(5)
7.43
11.22
0.193(4)
7.69
11.02
0.182(5)
7.71
15.62
–
–
–
Hinge angle (HA) [°][a]
Fold angle (FA) [°][a]
C*–Ru1[b]
Ru1–P1
Ru1–P2
Ru1–P3
Ru1–Cl1
1.913(5)
2.2568(14)
2.3160(14)
–
1.901(4)
2.2556(9)
2.2959(9)
–
1.973(5)
–
2.3120(13)
2.2479(14)
2.3170(13)
2.2858(14)
2.2844(13)
–
2.4194(14)
2.4434(9)
2.4443(13)
P1–Ru1–P2
P2–Ru1–P3
P1–Ru1–P3
P1–Ru1–Cl1
P2–Ru1–Cl1
96.71(5)
–
–
89.78(4)
90.56(5)
98.22(3)
–
–
90.99(3)
90.43(3)
88.81(5)
86.19(5)
87.93(5)
–
95.04(5)
–
–
93.20(5)
89.48(5)
–
[a] Slip-fold parameters as defined in ref.[15]. [b] C* = centroid of the five-membered ring, C1, C2, C3, C3a and C7a.
454 Eur. J. Inorg. Chem. 2007, 452–462
www.eurjic.org
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl]
FULL PAPER
thereby increasing the FA. This steric congestion is also re-
It was found that an 8-h reflux generated a 1:1:3:2 equi-
flected in the significantly longer C*–Ru1 bond length.
librium mixture of 1, free Josiphos, (R)-5 and (S)-5 dia-
The “ene” character of the “dangling” ethylindene sub- stereomers. Prolonged reaction time did not lead to comple-
stituent of LH in 2 was indicated by the short C3–C11 bond tion, but gave instead a decomposition product with a 31P
length [1.329(7) Å], of C–C double bond character.[16] The NMR resonance at δ = 24.9 ppm. Pure (R)-5 can be isolated
C–C bond lengths of the benzenoid ring have an average of by liquid chromatography of the mixture, with ‘loss’ of the
1.382 Å, consistent with aromaticity of the ring.[16]
(S)-5 isomer. Purification by fractional crystallisation was
The metric data for the structures of 2, 3 and [4]+ are rendered impossible by the similar solubility of 1 and 5.
significantly different from those of CpRu(dppf)Cl.[14]
A similar reaction of 1a with (R)-(S)-Josiphos (1:1) for
While the Ru1–P bond lengths in the latter complex are 1.5 h gave a 1.5:1 molar mixture of (R)- and (S)-[CpRu-
almost identical, the two Ru1–P bond lengths in each of (Josiphos)Cl] (6) diastereomers. Further heating caused epi-
2, 3 and [4]+ differ substantially, by 0.04–0.07 Å, probably merisation of (S)-6 to (R)-6, with complete conversion in
because of the steric repulsion between the benzenoid ring 8 h, indicating that (S)-6 is the kinetic product, while (R)-6
of the indenyl ligand and the phenyl rings bonded to P2, is the thermodynamically more stable isomer (Scheme 3).
which are situated directly below the benzenoid ring. The The simultaneous appearance of two new sets of doublets
Cp rings of dppf in 3 are almost eclipsed (synperiplanar), in the 31P NMR spectrum, corresponding to (R)-6 and (S)-
with a torsional angle (τ) of 4.3°, and the rings are tilted at 6, respectively, indicated that the chelation of Josiphos was
an angle of 6.3°. The P1–Ru1–P2 angle of 98.22° is larger a concerted process. This was unlike the stepwise process
than those in 2 and [4]+, undoubtedly because of the ex- observed in the analogous displacement reactions of 1a by
panse of the dppf ligand. However, the value, like that of other chiral diphosphanes.[18]
the Cp analogue (95.05°), falls in the range 91.6–102.2° re-
Pure (R)-6 can be isolated by either liquid chromatog-
raphy or by fractional crystallisation. Isolation of pure (S)-
6 was in vain, owing to epimerisation to (R)-6, despite
attempts to slow down the process by the presence of a free
ligand (see rate studies below); the process was found to be
accelerated on a silica-gel column.
ported for Ru(dppf) complexes.[17]
Synthesis of [(Cp/Ind)Ru(Josiphos)Cl]
Phosphane substitution of 1 or 1a by the ferrocene-based
chiral diphosphane ligand (R)-(–)-1-[(S)-2-(diphenylphos-
The configuration at the metal centre of 5 was deter-
mined by matching the coupling constants of the pair of
doublets observed in the 31P NMR spectrum to those of 6
[structurally determined (R)-6 possesses δ = 37.5 and
67.2 ppm (2JPP = 53.4 Hz) and (S)-6: δ = 49.3 and 68.1 ppm
(2JPP = 49.6 Hz)]. Based on these, the resonances for the
diastereoisomers of 5 were assigned as follows: a pair of
phanyl)ferrocenyl]ethyldicyclohexylphosphane
{(R)-(S)-
Josiphos} can likewise be achieved at an elevated tempera-
ture (Scheme 2). Because of the inequivalence of the two
phosphorus atoms in (R)-(S)-Josiphos and the pseudotetra-
hedral geometry of 1 and 1a, a pair of diastereomers is
formed, as displacement of PPh3 by chiral Josiphos gener-
ates a chiral ruthenium centre.
Scheme 2.
Scheme 3.
Eur. J. Inorg. Chem. 2007, 452–462
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
455

S. Y. Ng, G. Fang, W. K. Leong, L. Y. Goh, M. V. Garland
FULL PAPER
doublets at δ = 36.0 and 77.3 ppm (2JPP = 53.4 Hz) for (R)- cesses often determine the potential of chiral-at-metal com-
5, and δ = 60.5 and 68.4 ppm (2JPP = 49.6 Hz) for (S)-5. In plexes in homogeneous catalysis. Complex 6 was chosen to
the 1H NMR spectra of (R)-5 and (R)-6, the cyclohexyl be investigated rather than 5, as the latter is thermally un-
protons resonate as broad signals in the range δ = 0.6–2.7; stable.
the Me resonance sits on top of one of the broad signals.
1H and 31P NMR spectral observations of the reaction
The Cp protons of Josiphos in (R)-5 and (R)-6 resonate in of 1a with Josiphos showed that the rate of epimerisation
the range δ = 3.68–4.30. Protons signals at δ = 5.34 (H1) was markedly dependent on the concentration of free
and 5.73 (H2,3) are assignable to protons of η5-Ind in (R)- Josiphos in the reaction mixture. Thus, three experiments
5. In (R)-6, the protons of η5-CpRu are observed at δ = were carried out keeping Josiphos concentration [J] at
4.49 ppm.
10 m, and varying the molar ratio of 1a to Josiphos. The
The NMR spectroscopic data of (S) isomers of 5 and 6 results are given in Figure 5. In all three experiments, (R)-6
were obtained from spectra of their diastereoisomeric mix- and (S)-6 were formed in about 1.2:1 ratio in the first
tures by eliminating the resonances assigned to their (R) 10 min of the reactions. Subsequently, the ratio of (R)-6 to
isomers and the starting materials. The 31P resonances of (S)-6 increased rapidly in reactions A and B, as epimer-
both (S)-5 and (S)-6 can be easily identified, as they are isation proceeded at approximately similar rates, reaching a
very well resolved. However, their 1H resonances over- ratio of about 3 in 30 min, followed by a sharp increase to
lapped extensively with those of the corresponding (R) iso- 118 at 90 min (reaction A), and 83.5 at 100 min (reaction
mer, with the exception of the singlets at δ = 3.56 in (S)-5 B). It was observed that Josiphos was totally consumed at
and 3.89 in (S)-6, which belong to the protons of the Cp 30 min in reaction A, but was slowly consumed in reaction
ring of Josiphos.
B to a negligible amount at about 50 min. In reaction C,
The X-ray crystal structure of (R)-6 was obtained. A using a 0.5 molar excess of Josiphos, epimerisation was ob-
view of the molecule is shown in Figure 4, together with served to be extremely sluggish: the (R)-6/(S)-6 ratio re-
selected bond parameters. The cyclopentadienyl ring is mained at about 1.5 up to 135 min, followed by a slow in-
slightly distorted, with a hinge angle of 2.22° and ∆ of crease to about 10 in 500 min. This dramatic inhibition of
0.037 Å. The bond lengths of Ru1–P, Ru1–Cl1 and average epimerisation would suggest a dissociative type of mecha-
Ru1–C (of Cp ring) are comparable to those of (S)- nism, but the role of free Josiphos is currently still unclear
{RuCl(Cp)[(R)-dppp]}.[19] The longer Ru1–P2 compared to to us. This case, involving a bidentate biphosphane, would
Ru1–P1 is also observed in the crystal structure of trans- not be expected to exactly parallel that for phosphane sub-
RuCl2{(R)-(S)-Josiphos}(py)2.[20]
stitution in indenyl and CpRu(PPh3)2 complexes, for which
a dissociative mechanism had been proposed by Gimeno on
the basis of rate retardation by added PPh3.[11] Nonetheless,
the inhibitory effect of free Josiphos provides a useful way
to control the rate of epimerisation.
Figure 4. ORTEP diagram of (R)-6. Thermal ellipsoids are drawn
to 50% probability level. Hydrogen atoms are omitted for clarity.
Selected bond parameters: ∆ = 0.037(4) Å; HA = 2.22°; C*–Ru1
1.858(4) Å; Ru1–P1 2.2804(11) Å; Ru1–P2 2.3115(11) Å; Ru1–Cl1
2.4525(11) Å; P1–Ru1–P2 90.22(4)°; P1–Ru1–Cl1 89.22(4)°; P2–
Ru1–Cl1 90.41(4)°.
Epimerisation of 6
As both complexes 5 and 6 undergo S Ǟ R epimer-
isation, it would be desirable to investigate their configura-
tional stability and racemisation processes, as these pro- of 1a with Josiphos (J); [J] = 10 m.
Figure 5. A plot of the ratio of (R)-6/(S)-6 vs. time for the reaction
456 Eur. J. Inorg. Chem. 2007, 452–462
www.eurjic.org
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl]
FULL PAPER
Complex (R)-6 was observed to exhibit configurational acetylenic carbons, as we found that the reaction of 8 with
stability in solution indefinitely, even at elevated tempera- (CN)2CϵC(CN)2 or HCϵC(CO2Me) led to dissociation of
ture. As configurational stability is an asset for catalyst per- the indenyl ligand and did not yield any isolable product.
formance to give high enantioselectivity, (R)-6 has good
catalytic potential, especially for transfer hydrogenation of
ketones, as was found for chiral-at-metal organoruthenium
complexes.[21] Catalytic investigations of (R)-6 are currently
in progress in our laboratory.
Scheme 6.
Chloro Lability of [(Ind)Ru(dppf)Cl] (3)
The ORTEP diagrams for the molecular structures of 8
As in the case of 1 and 1a, chloro substitution of 3 pro- and 9 are shown in Figures 6 and 7, respectively.
vides a convenient pathway to new derivatives. It was found
that chloride abstraction with NaPF6 occurred readily in
CH3CN under reflux, giving the yellow acetonitrile
solvento complex [(Ind)Ru(dppf)(CH3CN)]PF6 ([7]PF6)
(Scheme 4). This compound was fully characterised spectro-
scopically (see Experimental Section). The Cp protons of
dppf display an ABCD pattern, similar to that in 3.
Scheme 4.
Figure 6. ORTEP diagram of 8. Thermal ellipsoids are drawn to
50% probability level. Hydrogen atoms are omitted for clarity. Se-
lected bond parameters: ∆ = 0.163 Å; HA = 6.85°; FA = 8.70°;
C*–Ru1 1.892 Å; Ru1–P1 2.2559(5) Å; Ru1–P 22.3251(6) Å; Ru–
N1 2.1355(18) Å; N1–N2 1.192(3) Å; N2–N3 1.156(3) Å; P1–Ru1–
P2 97.744(19)°; P1 Ru1–N1 84.42(5)°; P2–Ru1–N1 92.14(5)°; Ru1–
N1–N2 117.96(15)°; N3–N2–N1 176.6(2)°.
Treatment of 3 with NaN3 in ethanol at reflux for 4 h
afforded an 85% yield of 8 (Scheme 5), the spectral charac-
teristics of which are given in Experimental Section. Here
again, the Cp protons show an ABCD pattern.
Scheme 5.
As at PtII[22] and PdII[23] centres, the azido ligand in 8
undergoes [3+2] dipolar cycloaddition reaction with di-
methyl acetylenedicarboxylate, giving the N(2)-bound 4,5-
bis(methoxycarbonyl)-1,2,3-triazolato complex 9 in 55%
yield from an ambient temperature reaction (Scheme 6).
Several cycloaddition reactions have been reported in half-
sandwich ruthenium systems, like [(Ind)Ru(LL)(N3)],
Figure 7. ORTEP diagram of 9. Thermal ellipsoids are drawn to
50% probability level. Hydrogen atoms are omitted for clarity.
[Cp*Ru(LL)(N3)] (LL
=
dppm, dppe)[10f] and
[CpRu(dppe)(N3)].[24] This is a useful synthetic route to
The slip-fold parameters of 8 fall in the normal range for
some heterocycles, but it should be noted that the viability η5-coordination.[15] The Cp rings of the dppf ligand adopt
of the method may be dependent on the substituents on the a more stable synclinal staggered conformation, with tor-
Eur. J. Inorg. Chem. 2007, 452–462
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
457

S. Y. Ng, G. Fang, W. K. Leong, L. Y. Goh, M. V. Garland
Table 2. Selected bond lengths [Å] and angles [°] of 9 and [(Ind/Cp)Ru(dppe){N3C2(CO2Me)2}].
FULL PAPER
Complexes
9
[(Ind)Ru(dppe){N3C2(CO2Me)2}][10f]
[CpRu(dppe){N3C2(CO2Me)2}][24]
∆ [Å]
Hinge angle (HA) [°]
Fold angle (FA) [°]
0.142
5.25
9.63
0.175
–
–
–
–
–
C*–Ru1
Ru1–P1
Ru1–P2
Ru1–N2
N1–N2
N2–N3
N1–C15
N3–C14
C14–C15
1.909(8)
1.888(1)
2.2396(6)
2.2720(6)
2.0904(18)
1.336(3)
1.336(3)
1.348(3)
1.351(3)
1.395(3)
–
–
–
2.3230(18)
2.2646(18)
2.070(6)
1.306(8)
1.355(9)
1.352(10)
1.338(10)
1.385(11)
2.090(2)
1.331(3)
1.332(3)
1.351(3)
1.352(3)
1.400(4)
P1–Ru1–P2
P1–Ru1–N2
P2–Ru1–N2
Ru1–N2–N1
Ru1–N2–N3
N1–N2–N3
N2–N1–C15
N2–N3–C14
N1–C15–C14
N3–C14–C15
98.08(6)
91.35(17)
87.54(16)
126.4(5)
121.1(4)
112.2(6)
106.8(6)
105.3(6)
107.2(6)
108.5(7)
84.92(2)
86.38(5)
89.73(5)
–
85.13(3)
86.48(6)
89.89(6)
121.4(2)
125.2(2)
113.4(2)
105.6(2)
105.5(2)
107.7(2)
107.8(2)
–
112.95(17)
105.83(18)
108.29(19)
107.67(19)
108.29(19)
sional angle 39.09°. The Ru1–N1 bond length of
2.1355(18) Å falls within the range of reported values for
azido Ru complexes.[25] The coordinated terminal azido li-
gand is almost linear, the N3–N2–N1 angle being 176.6°.
In 9, Ru is coordinated to two phosphorus atoms of the
dppf ligand, heterocycle N3C2(CO2Me)2 through N(2) and
an η5-indenyl ligand. The coordination geometry of 9 is ef-
fectively similar to those of its Ind/Cp analogues containing
dppe.[10f,24] The only noticeable difference lies in the irregu-
larity of the pentagonal heterocyclic ring in 9. This un-
doubtedly is caused by the steric demands of the bulky dppf
ligand. It is seen in the structure of 9 that the heterocycle
is hemmed in by the phenyl rings of dppf; moreover, N3,
being nearer to the benzenoid ring of the indenyl ligand,
suffers from additional steric encumbrance, hence the short-
ened N2–N3 bond length.
Conclusions
(Ind)Ru(PPh3)2Cl has been prepared and mono-, di- and
trisubstitution derivatives have been obtained with the
monophosphane ligand LH, dppf and triphos, respectively.
(R) and (S) diastereomers have been obtained with
Josiphos, but only the thermodynamically stable (R) isomer
could be isolated pure. A similar result was obtained with
CpRu(PPh3)2Cl. A rate study by 1H NMR spectroscopy
showed Josiphos-dependent epimerisation of CpRu-
(Josiphos)Cl. Chloro substitution of (Ind)Ru(dppf)Cl with
–
CH3CN and N3 appears to indicate that this process is as
facile as in the well-studied complex CpRu(PPh3)2Cl. The
[3+2] dipolar cycloaddition of the azido ligand provides an
additional example for this uncommon occurrence at Ru.
Selected metric data of 9, including the slip-fold distor-
tion parameters, are listed in Table 2, which also gives the
metric data of its Ind/Cp dppe analogues for comparison.
While these analogues possess very similar bond param-
eters, these differ appreciably from those of 9, especially the
bond angles. These significant differences are no doubt a
consequence of the bulkiness of the dppf ligand.
Experimental Section
General: All reactions were carried out using conventional Schlenk
techniques under inert nitrogen or under argon in an M. Braun
Labmaster 130 Inert Gas System. NMR spectra were measured on
a Bruker 300 FT NMR spectrometer; for 1H and 31P spectra, chem-
ical shifts were referenced to residual H-signals of the deuterated
458
www.eurjic.org
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2007, 452–462

Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl]
FULL PAPER
solvents C6D6, CD3CN. IR spectra in KBr pellets were measured
in the range 4000–400 cm–1 with a BioRad FTS-165 FTIR instru-
ment. Mass spectra were run on a Finnigan Mat 95XL-T (FAB)
or a Finnigan-MAT LCQ (ESI) spectrometer. Elemental analyses
ture changed from red to yellow. The resultant yellow suspension
was filtered through Celite. The filtrate was concentrated to about
5 mL. Addition of ether (2 mL) gave yellow microcrystals, [(Ind)-
Ru(tripod)]PF6 ([4]PF6), after 1 d at –30 °C (51 mg, 83% yield).
X-ray diffraction-quality crystals were obtained from a saturated
solution of [4]PF6 in CH2Cl2 with ether layering after 2 d at –30 °C.
were performed by the microanalytical laboratory in-house. [(Ind)-
Ru(PPh3)2Cl] (1)[7] and C9H7(CH2)2PPh2
were prepared by the
[26]
published methods. All other chemicals were obtained commer-
cially and used without any further purification. All solvents were
dried with sodium/benzophenone and distilled before use. Celite
(Fluka AG), silica gel (Merck Kieselgel 60, 230–400 Mesh) were
dried at 140 °C overnight before chromatographic use. Conven-
tional numbering of indenyl protons is shown in Figure 8.
1
Data for [4]PF6: H NMR (300 MHz, CD3CN): δ = 1.56–1.57 (m,
3 H, Me), 2.39 (br. s, 6 H, CH2), 5.51 (d, 3JHH = 2.5 Hz, 2 H, H2,3),
5.70 (t, JHH = 2.5 Hz, 1 H, H1), 6.78–6.82 (br. s, 12 H, Ph), 7.04
3
3
3
(t, JHH = 7.4 Hz, 12 H, Ph), 7.22 (t, JHH = 7.4 Hz, 6 H, Ph),
7.31–7.34 and 7.43–7.47 (each m, 2 H, H4–7) ppm. 31P{1H} NMR:
δ = 39.9 (s, tripod), –142.9 (septet, PF ) ppm. IR (KBr): ν = 058
˜
6
(w), 2923 (w), 2868 (w), 1482 (w), 1434 (m), 1092 (m), 839 [vs.
(PF6)], 744 (m), 697 (s), 557 [m (PF6)], 517 (s) cm–1. FAB+-MS:
m/z (%)
= =
841 [M]+. FAB–-MS: m/z (%) 145 [PF6]–.
C50H46F6P4Ru (985.86): calcd. C 60.9, H 4.7; found C 60.5, H 5.2.
Synthesis of [(Ind)Ru{(R)-(S)-Josiphos}Cl] (5): (R)-(–)-1-[(S)-2-(Di-
phenylphosphanyl)ferrocenyl]ethyldicyclohexylphosphane
{(R)-
Figure 8. Numbering of indenyl protons.
(S)-Josiphos} (23 mg, 0.04 mmol) was added to a red solution of 1
(30 mg, 0.04 mmol) in toluene (5 mL) and the mixture was re-
fluxed. The reaction was monitored using 31P NMR spectroscopy.
Refluxing was ceased when the ratio of starting materials and prod-
uct remained constant (about 8 h). The solution was concentrated
to about 2 mL and loaded onto a silica gel column (2ϫ8 cm) pre-
pared in n-hexane. Elution gave three fractions: (i) a yellow eluate
in hexane/diethyl ether (1:1, about 4 mL), which recovered free (R)-
(S)-Josiphos (2 mg, 9% recovery); (ii) an orange-red solution in
hexane/diethyl ether (1:1, about 15 mL), which yielded [(R)-(Ind)-
Ru{(R)-(S)-Josiphos}Cl] [(R)-5] (12 mg, 37% yield) as orange sol-
ids; and (iii) a red solution in THF (about 3 mL), which recovered
unreacted 1 (2 mg, 7% recovery).
Synthesis of [(Ind)Ru(PPh3){Ph2P(CH2)2C9H7}Cl] (2): C9H7(CH2)2-
PPh2 (35 mg, 0.11 mmol) was added to a red solution of 1 (70 mg,
0.09 mmol) in toluene (10 mL). The mixture was heated at 80 °C
for 4 h. The resultant red solution was concentrated to about 1 mL
and eluted through a silica gel column (2ϫ2 cm) prepared in n-
hexane with toluene/diethyl ether (10:1). From the red eluate, red
microcrystals of [(Ind)Ru(PPh3){Ph2P(CH2)2C9H7}Cl] (2) (57 mg,
75% yield) were obtained upon recrystallisation from THF/hexane.
X-ray diffraction-quality crystals were obtained from a concen-
trated ether solution with hexane layering after 2 d at –30 °C.
Data for 2: 1H NMR (300 MHz, C6D6): δ = 1.73–1.90 (br. m, 1 H,
CH2), 2.18–2.30 (br. m, 1 H, CH2), 2.93 (s, 2 H, CH2 on IndH),
3.15 (s, 1 H, CH2), 3.40–3.52 (m, 1 H, CH2), 4.95–5.00 (m, 2 H,
H2,3), 5.78 (s, 1 H, H1), 6.57–6.60 (d-like m, 1 H, IndH), 6.79–6.81,
6.84–6.94, 6.98–7.13, 7.19–7.22 (each m, total 29 H, H4–7and Ph),
7.65–7.68 (d-like m, 1 H, Ph), 8.25 (t-like m, 2 H, Ph) ppm. 31P{1H}
NMR: δ = 46.5, 50.0 [each d, 2JPP = 42.9 Hz, PPh3 and IndH(CH2)2-
PPh2] ppm. FAB+-MS: m/z (%) = 842 [M]+, 808 [M – Cl]+, 691
[M – Ind]+, 581 [M – PPh3]+, 545 [M – PPh3 – Cl]+, 479 [M –
1
Data for (R)-5: H NMR (300 MHz, C6D6): δ = 0.87–1.10 (br. m,
6 H, Cy), 1.24–1.56 (br. m) with 1.47 (dd, sitting on top of br. m,
3JHH = 7.41, 2JHP = 9.9 Hz, total 11 H, Cy and Me), 1.63–1.68 (br.
m, 1 H, Cy), 1.76–1.85 (br. m, 2 H, Cy), 1.94–1.98 (br. m, 2 H,
Cy), 2.18–2.32, 2.37–2.50 and 2.60–2.68 (each br. m, 1 H, Cy), 3.68
(s, 5 H, Cp), 4.06 (t-linked m, 1 H, Cp), 4.19 and 4.23 (each br. s,
1 H, Cp), 5.22–5.29 [m, 1 H, CHMeP(Cy)2], 5.34 (s, 1 H, H1), 5.73
(s, 2 H, H2,3), 6.89–6.94, 6.99–7.08, 7.11–7.16, 7.24–7.30, 7.44–7.49,
7.52–7.59 and 7.75–7.78 (each m, total 14 H, H4–7 and Ph) ppm.
31P{1H} NMR: δ = 36.0 (d, 2JPP = 53.4 Hz, Josiphos), 77.3 (d, 2JPP
= 53.4 Hz, Josiphos) ppm. FAB+-MS: m/z (%) = 846 [M]+, 812
[M – Cl]+. C45H51ClFeP2Ru (846.20): calcd. C 63.9, H 6.1; found
C 63.9, H 6.3.
IndH(CH2)2PPh2
– – Ind – PPh3 –
Cl]+, 429 [M Cl]+.
C50H43ClP2Ru (842.35): calcd. C 71.3, H 5.2; found C 71.6, H 5.3.
Synthesis of [(Ind)Ru(dppf)Cl] (3): 1,1Ј-Bis(diphenylphosphanyl)fer-
rocene (dppf) (0.76 g, 1.37 mmol) was added to a red solution of 1
(1 g, 1.29 mmol) in toluene (15 mL) and the mixture refluxed for
2 h. Red air- and moisture-stable crystalline solids, [(Ind)Ru(dppf)-
Cl] 3, precipitated out from the solution and were filtered (0.62 g,
60% yield). The supernatant was concentrated to about 5 mL. Ad-
dition of hexane (about 2 mL) gave a second crop after 2 h at 0 °C
(0.27 g, 26% yield). In solution, the red compound of 3 decom-
posed in air within a day to a brown species. X-ray diffraction-
quality crystals were obtained from a saturated solution of 3 in
C6D6 after a day at room temperature.
Synthesis of [CpRu{(R)-(S)-Josiphos}Cl] (6): (R)-(S)-Josiphos
(18 mg, 0.03 mmol) was added to a yellow solution of 1a (30 mg,
0.04 mmol) in toluene (5 mL) and the mixture was refluxed for 8 h.
The solvent was removed in vacuo and the residue extracted using
ether (3ϫ2 mL).
Purification Method (i): The ether extract was concentrated to
about 1 mL and loaded onto a silica gel column (2ϫ4 cm) pre-
pared in n-hexane. Elution gave two fractions: (i) a yellow eluate in
hexane/diethyl ether (5:1, about 20 mL), which yielded [(R)-
CpRu{(R)-(S)-Josiphos}Cl] [(R)-6] (28 mg, 85% yield) as orange
microcrystals; and (ii) a yellow solution in hexane/diethyl ether (1:1,
about 3 mL), which gave unreacted 1a (6 mg, 20% recovery).
Data for 3: 1H NMR (300 MHz, C6D6): δ = 3.66, 3.83, 3.90 and
3
4.20 (each s, 2 H, C5H4), 4.66 (t, JHH = 2.5 Hz, 1 H, H1), 5.57 (s,
2 H, H2,3), 7.01–7.13 and 7.47–7.58 (m, 24 H, H4–7 and Ph) ppm.
31P{1H} NMR: δ = 51.9 (s, dppf) ppm. FAB+-MS: m/z (5) = 806
[M]+, 771 [M – Cl]+, 655 [M – Cl – Ind]+. C43H35ClFeP2Ru
(806.05): calcd. C 64.1, H 4.4; found C 64.3, H 4.1.
Purification Method (ii): The ether extract was concentrated to
Synthesis of [(Ind)Ru(tripod)]PF6 ([4]PF6): NaPF6 (20 mg, about 1 mL and hexane was added (about 2 mL). Orange solids of
0.12 mmol) and tripod (40 mg, 0.06 mmol) were added to a red
solution of 1 (50 mg, 0.06 mmol) in toluene/THF (5:1, 12 mL). The
mixture was refluxed for 4 h, during which the colour of the mix-
1a were recovered after 1 d at –30 °C, and removed by filtration
(5 mg, 16% recovery). The mother liquor was concentrated to
about 1 mL and hexane was added (about 4 mL). Orange yellow
Eur. J. Inorg. Chem. 2007, 452–462
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
459

S. Y. Ng, G. Fang, W. K. Leong, L. Y. Goh, M. V. Garland
FULL PAPER
solids of (R)-6 were obtained after 1 d at –30 °C (15 mg, 46%
yield). Subsequently, four additional crops of (R)-6 were obtained,
each about 3 mg (total 11 mg, 34% yield). X-ray diffraction-quality
crystals were obtained from a concentrated ether solution with hex-
ane layering after a day at –30 °C.
in CH3CN (10 mL) and the mixture was refluxed. The colour of
the suspension changed slowly from red to yellow in 4 h. The sus-
pension was filtered and the filtrate was evacuated to dryness. The
residue was redissolved in THF (about 4 mL) and hexane (about
2 mL) was added. Yellow crystals of [(Ind)Ru(dppf)(CH3CN)]PF6
([7]PF6) (55 mg, 93% yield) were obtained after 1 d at –30 °C.
1
Data for (R)-6: H NMR (300 MHz, C6D6): δ = 0.61–0.77 (br. m,
2 H, Cy), 1.29–1.55 (br. m) with 1.52 (dd, sitting on top of br. m,
Data for [7]PF6: 1H NMR (300 MHz, CDCl3): δ = 2.15 (s, 3 H,
CH3CN), 4.22, 4.33 and 4.35 (each s, 2 H, C5H4), 4.44 (br. s, 3 H,
2
3JHH = 7.41, JHP = 9.06 Hz, total 13 H, Cy and Me), 1.65–1.92
3
(br. m, 6 H, Cy), 2.09–2.18 and 2.41–2.46 (each br. m, 2 H, Cy),
C5H4 and H1), 4.60 (d, JHH = 2.5 Hz, 2 H, H2,3), 6.63–6.66 and
3
3.79 (s, 5 H, Cp), 4.11 (t, JHH = 2.49 Hz, 1 H, Cp), 4.27 and 4.30
7.18–7.21 (each 4-line m, 2 H, H4–7), 6.82–6.88, 7.28–7.33, 7.40–
7.52 (m, 20 H, Ph) ppm. 31P{1H} NMR: δ = 50.7 (s, dppf), –144.1
(each br. s, 1 H, Cp), 4.49 (s, 5 H, η5-CpRu), 5.23–5.34 [m, 1 H,
CHMeP(Cy)2], 6.85–6.90 and 7.20–7.23 (each m, 1 H, Ph), 6.93–
6.97, 7.01–7.06 and 7.31–7.36 (each m, 2 H, Ph), 8.71 (br. s, 2 H,
(septet, PF ) ppm. IR (KBr): ν = 055 (w), 2974 (w), 2057 (w), 2276
˜
6
[w (CN)], 1481 (m), 1435 (m), 1158 (m), 1092 (m), 840 [vs. (PF6)],
749 (s), 699 (s), 557 [s (PF6)], 514 (m) cm–1. FAB+-MS: m/z (%) =
812 [M]+, 771 [M – CH3CN]+, 655 [M – CH3CN – C9H7]+. FAB–-
2
Ph) ppm. 31P{1H} NMR: δ = 37.5 (d, JPP = 53.4 Hz, Josiphos),
2
67.2 (d, JPP = 53.4 Hz, Josiphos) ppm. FAB+-MS: m/z (%) = 846
[M]+, 812 [M – Cl]+. C41H49ClFeP2Ru·(CH3CH2)2O (870.26): MS: m/z (%) = 145 [PF6]–. C45H38F6FeNP3Ru·½CH3CN (977.16):
calcd. C 62.1, H 6.8; found C 62.2, H 6.8.
calcd. C 56.5, H 4.0, N 2.2; found C 56.0, H 3.9, N 2.1.
Epimerisation Kinetics: Complex 1a [2.4 mg, 3.3 mmol (reaction A);
Synthesis of [(Ind)Ru(dppf)N3] (8): NaN3 (20 mg, 0.3 mmol) was
3.6 mg, 5 mmol (reaction B); 5.4 mg, 7.5 mmol (reaction C)] and added to a red suspension of 3 (50 mg, 0.06 mmol) in EtOH
(R)-(S)-Josiphos (3.0 mg, 5.0 mmol) were added to three different
NMR tubes in three different ratios, that is, 1:1.5, 1:1 and 1.5:1.
[D8]toluene (0.5 mL) was added into each NMR tube. The initial
1H and 31P NMR spectrum of each reaction mixture was measured,
and then at intervals during the reaction at 100 °C. The concentra-
tion of each component in the reaction mixtures was obtained from
the integration of the Cp protons of the Josiphos [δ = 3.71 in (R)-
6 and δ = 3.89 in (S)-6], using as internal standard the residual
0.1% H-signal of 99.9% [D8]toluene.
(10 mL) and the mixture was refluxed for 4 h. The solvent was re-
moved in vacuo and the red residue extracted using CH2Cl2
(2ϫ4 mL). The extract was concentrated to about 3 mL and hex-
ane (about 10 mL) was added. After being kept overnight at
–30 °C, red crystals of [(Ind)Ru(dppf)N3] 8 (43 mg, 85% yield) were
obtained. X-ray diffraction-quality crystals were obtained from a
saturated solution in CH2Cl2 with hexane layering after 2 d at
–30 °C.
Data for 8: 1H NMR (300 MHz, C6D6): δ = 3.79, 4.05, 4.21 and
Synthesis of [(Ind)Ru(dppf)(CH3CN)]PF6 ([7]PF6): NaPF6 (16 mg,
4.29 (each s, 2 H, C5H4), 4.58 (s, 1 H, H1), 4.79 (s, 2 H, H2,3), 7.09–
0.09 mmol) was added to a red suspension of 3 (50 mg, 0.06 mmol) 7.12, 7.14–7.23, 7.26–7.29, 7.39–7.44, 7.47–7.52 (each m, total 24
Table 3. Crystal and structure refinement data.
2
3
[4]PF6
Formula
Formula mass
Space group
C54H53ClOP2Ru
916.42
P21/c
C43H35ClFeP2Ru
806.02
P21/c
C51.5H49Cl3F6P4Ru
1113.21
P1
¯
Crystal system
monoclinic
monoclinic
triclinic
Unit cell dimensions
a [Å]
b [Å]
c [Å]
12.433(5)
15.543(6)
23.785(9)
90
11.5291(5)
29.8651(15)
11.3638(5)
90
12.5364(5)
13.2396(5)
15.9901(6)
98.356(1)
α [°]
β [°]
γ [°]
101.836(10)
90
4499(3)
118.9740(10)
90
3423.0(3)
4
1.564
1.069
103.723(1)
92.325(1)
2543.08(17)
2
1.454
0.648
Cell volume [Å3]
Z
4
Dcalcd [gcm–3]
Absorption coefficient [mm–1]
F(000) electrons
Crystal size [mm3]
θ range for data collection [°]
Index ranges
1.353
0.518
1904
0.16ϫ0.09ϫ0.09
2.13–25.00
–14 Յ h Յ 14
–18 Յ k Յ 17
–28 Յ l Յ 16
26102
1640
1134
0.28ϫ0.14ϫ0.08
2.02–27.50
–12 Յ h Յ 14
–28 Յ k Յ 38
–14 Յ l Յ 14
24177
0.22ϫ0.12ϫ0.04
2.20–26.37
–15 Յ h Յ 15
–16 Յ k Յ 16
0 Յ l Յ 19
36189
Reflections collected
Independent reflections
Max. and min. transmission
Data/restraints/parameters
Gof
7923
7849
10372
0.9549 and 0.9217
7923/0/532
0.980
0.9194 and 0.7540
7849/0/433
1.095
0.9745 and 0.8705
10372/18/612
1.038
Final R indices [I Ͼ 2σ(I)]
R1 = 0.0542
wR2 = 0.0965
R1 = 0.1004
wR2 = 0.1097
0.565 and –0.400
R1 = 0.0491
wR2 = 0.0981
R1 = 0.0649
wR2 = 0.1037
0.738 and –0.500
R1 = 0.0648
wR2 = 0.1862
R1 = 0.0845
wR2 = 0.2032
2.127 and –0.421
R indices (all data)
Largest diff. peak and hole [eÅ–3]
460
www.eurjic.org
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2007, 452–462

Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl]
FULL PAPER
Table 4. Crystal and structure refinement data.
(R)-6
8
9
Formula
Formula mass
C43H54ClFeO0.50P2Ru
833.17
C43H35FeN3P2Ru
897.53
C51.50H46Cl5FeN3O4P2Ru
1167.02
Space group
Crystal system
P212121
orthorhombic
P21/n
monoclinic
P21/c
monoclinic
Unit cell dimensions
a [Å]
b [Å]
c [Å]
9.546(2)
11.3220(3)
14.5824(3)
23.3452(5)
90
17.8241(14)
11.6367(10)
25.689(2)
90
20.204(4)
21.200(4)
90
α [°]
β [°]
γ [°]
90
90
96.5650(10)
90
3829.06(16)
4
1.557
1.034
103.167(2)
90
5188.2(7)
4
1.494
0.937
Cell volume [Å3]
Z
4088.9(15)
4
1.353
0.897
1732
0.30ϫ0.22ϫ0.10
2.02–30.51
–13 Յ h Յ 13
0 Յ k Յ 28
0 Յ l Յ 30
61668
Dcalcd [gcm–3]
Absorption coefficient [mm–1]
F(000) electrons
Crystal size [mm3]
θ range for data collection [°]
Index ranges
1824
2372
0.34ϫ0.20ϫ0.10
2.10–26.37
–14 Յ h Յ 14
0 Յ k Յ 18
0 Յ l Յ 29
35653
0.32ϫ0.18ϫ0.14
2.11–26.37
–22 Յ h Յ 21
0 Յ k Յ 14
0 Յ l Յ 32
42001
Reflections collected
Independent reflections
Max. and min. transmission
Data/restraints/parameters
Gof
11860
7793
10631
0.9156 and 0.7746
11860/2/434
1.199
0.9037 and 0.7201
7793/0/478
1.056
0.8800 and 0.7537
10631/28/625
1.137
Final R indices [I Ͼ 2σ(I)]
R1 = 0.0484
wR2 = 0.1292
R1 = 0.0535
wR2 = 0.1322
1.004 and –0.498
R1 = 0.0450
wR2 = 0.1091
R1 = 0.0569
wR2 = 0.1159
1.345 and –1.054
R1 = 0.0881
wR2 = 0.2225
R1 = 0.1148
wR2 = 0.2373
1.925 and –1.013
R indices (all data)
Largest diff. peak and hole [eÅ–3]
H, H4–7 and Ph) ppm. 31P{1H} NMR: δ = 52.5 (s, dppf) ppm. IR
(KBr): ν = 053 (w), 2025 [vs. (N )], 1433 (w), 1159 (w), 1091 (w), SHELXTL suite of programs.[30] Crystal and structure refinement
Structural solution and refinement were carried out with the
˜
3
1034 (w), 745 (m), 697 (m), 513 (m) cm–1. FAB+-MS: m/z (%) =
785 [M – N2]+, 771 [M – N3]+, 670 [M – Ind – N2]+, 655 [M –
Ind – N3]+. C43H35FeN3P2Ru (812.62): calcd. C 63.6, H 4.3, N 5.2;
found C 63.5, H 4.8, N 5.2.
data are summarised in Tables 3 and 4. The structures were solved
by direct methods or Patterson maps to locate the heavy atoms,
followed by difference maps for the light, non-hydrogen atoms. All
non-hydrogen atoms were generally given anisotropic displacement
parameters in the final model.
Synthesis of [(Ind)Ru(dppf){N3C2(CO2Me)2}] (9): Dimethyl ace-
tylenedicarboxylate (38 µL, 0.31 mmol) was added into a red solu-
tion of 8 (50 mg, 0.06 mmol) in CH2Cl2 (10 mL) and the reaction
mixture was stirred at room temperature for 24 h. The colour of
the solution slowly changed from red to orange-red. The solution
was concentrated to about 2 mL and hexane (8 mL) was added.
Yellow crystals [(Ind)Ru(dppf){N3C2(CO2Me)2}] 9 (33 mg, 55%
yield) were obtained after 18 h at –10 °C. X-ray diffraction-quality
crystals were obtained from a saturated solution in CH2Cl2 with
ether layering after 1 week at 4 °C.
Data for 9: 1H NMR (300 MHz, C6D6): δ = 3.52 (s, 6 H, Me), 3.76,
4.10, 4.31 and 4.34 (each s, 2 H, C5H4), 4.78 (s, 1 H, H1), 5.35 (s,
2 H, H2,3), 6.86–6.90 (m, 2 H, H4–7), 6.96–6.97, 7.16–7.43, 7.72–
7.78 (each m, total 22 H, H4–7 and Ph) ppm. 31P{1H} NMR: δ =
CCDC-616431 to -616436 contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
Acknowledgments
The authors acknowledge with thanks support from the Academic
Research Fund (grant no. 143-000-209-112) to L. Y. G., Institute of
Chemical and Engineering Sciences for a research scholarship to
S. Y. N. and technical assistance from Dr. L. L. Koh and Ms. G. K.
Tan for X-ray structure determinations of 2 and 3.
56.8 (s, dppf) ppm. IR (KBr): ν = 057 (w), 2945 (w), 1736 [vs.
˜
[1] See for instance the following: a) C. A. Tolman, Chem. Rev.
1977, 77, 313; b) D. J. Darensbourg, A. H. Graves, Inorg.
Chem. 1979, 18, 1257; c) J. D. Atwood, M. J. Wovkulich, D. C.
Sonnenberger, Acc. Chem. Res. 1983, 16, 350; d) R. L. Harlow,
R. J. McKinney, J. F. Whitney, Organometallics 1983, 2, 1839;
e) A. G. Orpen, N. G. Connelly, J. Chem. Soc., Chem. Commun.
1985, 1310.
[2] See for instance the following: a) L. Dahlenburg, Coord. Chem.
Rev. 2005, 249, 2962; b) N. Mézailles, L. Ricard, F. Gagosz,
Org. Lett. 2005, 7, 4133; c) A. D. Phillips, L. Gonsalvi, A. Ro-
merosa, F. Vizza, M. Peruzzini, Coord. Chem. Rev. 2004, 248,
(C=O)], 1434 [m (N=N)], 1292 [m (C–O)], 1165 (m), 1087 (s), 772
(m), 697 (m), 508 (m) cm–1. FAB+-MS: m/z 955 [M]+, 771 [M –
N3C2(CO2Me)2]+. C49H41FeN3O4P2Ru (954.73): calcd. C 61.6, H
4.3, N 4.4; found C 61.7, H 3.8, N 4.4.
Crystal Structure Determinations: Crystals were mounted on quartz
fibres. X-ray data were collected on a Bruker AXS APEX system,
using Mo-Kα radiation, with the SMART suite of programs.[27]
Data were processed and corrected for Lorentz and polarisation
effects with SAINT,[28] and for absorption effects with SADABS.[29]
Eur. J. Inorg. Chem. 2007, 452–462
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
461

S. Y. Ng, G. Fang, W. K. Leong, L. Y. Goh, M. V. Garland
FULL PAPER
955; d) S. R. Klei, T. D. Tilley, R. G. Bergman, Organometallics
2002, 21, 4905; e) D. Ferraris, B. Young, T. Dudding, T. Lectka,
J. Am. Chem. Soc. 1998, 120, 4548; f) J. P. Wolfe, S. Wagaw,
S. L. Buchwald, J. Am. Chem. Soc. 1996, 118, 7215.
[11]
M. P. Gamasa, J. Gimeno, C. Gonzalez-Bernardo, B. M. Mar-
tin-Vaca, D. Monti, M. Bassetti, Organometallics 1996, 15, 302.
J. J. Bishop, A. Davison, Inorg. Chem. 1971, 10, 826.
a) D. Gareau, C. Sui-Seng, L. F. Groux, F. Brisse, D. Zarg-
arian, Organometallics 2005, 24, 4003; b) D. Zargarian, Coord.
Chem. Rev. 2002, 233–234, 157.
[12]
[13]
[3] J. D. Gilbert, G. Wilkinson, J. Chem. Soc. A 1969, 1749.
[4] a) S. G. Davies, J. P. McNally, A. J. Smallridge, Adv. Or-
ganomet. Chem. 1990, 30, 1; b) T. Blackmore, M. I. Bruce,
F. G. A. Stone, J. Chem. Soc. A 1971, 2376; c) M. I. Bruce, N. J.
Windsor, Aust. J. Chem. 1977, 30, 1601; d) G. S. Ashby, M. I.
Bruce, I. B. Tomkins, R. C. Wallis, Aust. J. Chem. 1979, 32,
1003; e) M. I. Bruce, F. S. Wong, B. W. Skelton, A. H. White,
J. Chem. Soc., Dalton Trans. 1981, 1398; f) M. I. Bruce, M. G.
Humphery, J. M. Patrick, A. H. White, Aust. J. Chem. 1983,
36, 2065.
[14]
[15]
X. L. Lu, Ph.D Thesis, National University of Singapore, Sin-
gapore, 2002.
5
For indenyl complexes containing undistorted η rings: ∆ =
0.03 Å, HA = 2.5°, FA = 4.4°; for those containing distorted
η5 rings: ∆ = 0.11–0.42 Å, HA = 7–14°, FA = 6–13°; and for
those wherein the five-membered ring is η3-coordinated: ∆ =
0.8 Å, FA = 28°. See: A. K. Kakkar, N. J. Taylor, T. B. Marder,
J. K. Shen, N. Hallinan, F. Basolo, Inorg. Chim. Acta 1992,
198–200, 219.
[5] a) V. Cadierno, P. Crochet, S. E. García-Carrido, J. Gimeno,
Dalton Trans. 2004, 3635; b) Y. Wakatsuki, M. Tokunaga, An-
gew. Chem. Int. Ed. Engl. 1998, 37, 2867; c) D. B. Grotjahn, [16]
D. A. Lev, J. Am. Chem. Soc. 2004, 126, 12232; d) Y. Wakatsui,
L. Pauling, The Nature of the Chemical Bond, Cornell Univer-
sity Press, Ithaca, NY, 1960, chapter 7, p. 221.
M. Tokunaga, T. Suzuki, Org. Lett. 2001, 3, 735; e) Y. Wakat-
suki, A. Horiuchi, J. Am. Chem. Soc. 2001, 123, 11917.
[6] a) K.-S. Gan, T. S. A. Hor in Ferrocenes: Homogeneous Cataly-
sis, Organic Synthesis and Materials Science (Eds.: A. Togni, T.
Hayashi), Wiley-VCH, Weinheim, Germany, 1995, p. 3; b) H.-
U. Blaser, W. Brieden, B. Pugin, F. Spindler, M. Studer, A.
Togni, Top. Catal. 2002, 19, 3.
[7] L. A. Oro, M. A. Ciriano, M. Campo, J. Organomet. Chem.
1985, 289, 117.
[8] V. Cadierno, J. Díez, M. P. Gamasa, J. Gimeno, E. Lastra, Co-
ord. Chem. Rev. 1999, 193–195, 147 and references cited
therein.
[9] See for example the following and references cited therein: a)
J. Díez, M. P. Gamasa, J. Gimeno, E. Lastra, A. Villar, Organo-
metallics 2005, 24, 1410; b) S. Conejero, J. Díez, M. P. Gamasa,
J. Gimeno, Organometallics 2004, 23, 6299; c) M. Bassetti, P.
Alvarez, J. Gimeno, E. Lastra, Organometallics 2004, 23, 5127;
d) P. Alvarez, E. Lastra, J. Gimeno, M. Bassetti, L. R. Falvello,
J. Am. Chem. Soc. 2003, 125, 2386; e) V. Cadierno, M. P. Gam-
asa, J. Gimeno, C. González-Bernardo, E. Pérez-Carreño, S.
García-Granda, Organometallics 2001, 20, 5177.
[17]
[18]
G. Bandoli, A. Dolmella, Coord. Chem. Rev. 2000, 209, 161.
G. Consiglio, F. Morandini, F. Bangerter, Inorg. Chem. 1982,
21, 455.
F. Morandini, G. Consiglio, B. Straub, G. Ciani, A. Sironi, J.
Chem. Soc., Dalton Trans. 1983, 2293.
C. G. Leong, O. M. Akotsi, M. J. Ferguson, S. H. Bergens,
[19]
[20]
Chem. Commun. 2003, 750.
[21] J.-B. Sortais, V. Ritleng, A. Voelklin, A. Holuigue, H. Smail, L.
Barloy, C. Sirlin, G. K. M. Verzijl, J. A. F. Boogers, A. H. M.
de Vries, J. G. de Vries, M. Pfeffer, Org. Lett. 2005, 7, 1247.
[22] a) W. Beck, K. Schropp, Chem. Ber. 1975, 108, 3317; b) W. P.
Fehlhammer, L. F. Dahl, J. Am. Chem. Soc. 1972, 94, 3370.
[23] T. Kemmerich, J. H. Nelson, N. E. Takach, H. Boeheme, B.
Jablonski, W. Beck, Inorg. Chem. 1982, 21, 1226.
[24] C. W. Chang, G. H. Lee, Organometallics 2003, 22, 3107 and
references cited therein.
[25] P. Govindaswamy, P. J. Carroll, Y. A. Mozharivskyj, M. R.
Kollipara, J. Organomet. Chem. 2005, 690, 885.
[26] Y. Kataoka, Y. Iwato, T. Yamagata, K. Tani, Organometallics
1999, 18, 5423.
[10] a) K. M. Rao, E. K. Rymmai, Polyhedron 2003, 22, 307; b) S. S. [27] SMART version 5.628, Bruker AXS Inc., Madison, WI, USA,
Keisham, Y. A. Mozharivskyj, P. J. Carroll, M. R. Kollipara, J. 2001.
Organomet. Chem. 2004, 689, 1249; c) K. S. Singh, G. P. A. [28] SAINT+ version 6.22a, Bruker AXS Inc., Madison, WI, USA,
Yap, K. A. Kreisel, M. R. Kollipara, J. Coord. Chem. 2005, 58,
1607; d) P. Govindaswamy, C. Sinha, M. R. Kollipara, J. Or-
ganomet. Chem. 2005, 690, 3465; e) K. S. Singh, Y. A. Mozah-
rivskyj, C. Thöne, M. R. Kollipara, J. Organomet. Chem. 2005,
690, 3720; f) K. S. Singh, C. Thöne, M. R. Kollipara, J. Or-
ganomet. Chem. 2005, 690, 4222; g) K. S. Singh, C. Thöne,
M. R. Kollipara, J. Coord. Chem. 2006, 59, 333.
2001.
[29] G. M. Sheldrick, SADABS, University of Göttingen, Germany,
1996.
[30] SHELXTL version 5.1, Bruker AXS Inc., Madison, WI, USA,
1997.
Received: August 3, 2006
Published Online: November 28, 2006
462
www.eurjic.org
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2007, 452–462