Synthesis and characterization of (CH=CH)3-bridged heterobimetallic ferrocene-ruthenium complexes

Article abstract of DOI:10.1021/om0490637

The complex Fc(CH=CH)₂C≡C-TMS (Fc = ferrocenyl) was obtained from Wittig olefination of FcCH₂PPh₃Br with TMS-C≡CCH=CHCHO in THF. The conjugated monometallic diene can be desilylated to give Fc(CH=CH)₂C≡CH, which

Full text of DOI:10.1021/om0490637

1452
Organometallics 2005, 24, 1452-1457
Synthesis and Characterization of (CHdCH)3-Bridged
Heterobimetallic Ferrocene-Ruthenium Complexes
Ping Yuan,† Sheng Hua Liu,*,† Weicheng Xiong,† Jun Yin,† Guang-ao Yu,†
Ho Yung Sung,‡ Ian D. Williams,‡ and Guochen Jia‡
Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry,
Central China Normal University, Wuhan 430079, People’s Republic of China, and
Department of Chemistry, The Hong Kong University of Science and Technology,
Clear Water Bay, Kowloon, Hong Kong
Received November 30, 2004
The complex Fc(CHdCH)2CtC-TMS (Fc ) ferrocenyl) was obtained from Wittig olefination
of FcCH2PPh3Br with TMS-CtCCHdCHCHO in THF. The conjugated monometallic diene
can be desilylated to give Fc(CHdCH)2CtCH, which reacted with RuHCl(CO)(PPh3)3 to
produce Fc(CHdCH)3RuCl(CO)(PPh3)2. Treatment of the latter complex with PMe3, 4-phe-
nylpyridine (PhPy), 2,6-(Ph2PCH2)2C5H3N (PMP), and KTp (Tp ) hydridotris(pyrazolyl)-
borate) gave Fc(CHdCH)3RuCl(CO)(PMe3)3, Fc(CHdCH)3RuCl(CO)(PhPy)(PPh3)2, Fc(CHd
CH)3RuCl(CO)(PMP), and Fc(CHdCH)3RuTp(CO)(PPh3), respectively. The structures of
Fc(CHdCH)2CtCH and Fc(CHdCH)3RuCl(CO)(PMe3)3 have been confirmed by X-ray
diffraction.
Introduction
C1, C2, C3, C4, C5, C6, C8, C10, C12, C16, and C20 adducts
have been isolated.4-13 In contrast, very few studies
have been carried out with bimetallic complexes with
polyenediyl bridges, despite the fact that many conju-
gated organic materials (e.g. polyacetylenes, push/pull
stilbenes) have only sp2-hybridized carbon in their
backbones and polyacetylenes have high electrical con-
ductivity (up to 105 S cm-1) upon doping.14 Nonbranched
monodisperse π-conjugated oligoenes R(CR′dCR′′)nR (R′,
R′′ ) H, Me, R ) Ar, CHO, n ) 3, 5, ..., 11) have been
synthesized, and they have promising electronic and
Bimetallic and polymetallic complexes with conju-
gated hydrocarbon ligands bridging metal centers are
attracting considerable current interest.1,2 Bimetallic
complexes with polyynediyl bridges, M-(CtC)n-M′,
constitute the most fundamental class of carbon-based
molecular wires, and they have been proposed for
construction of nanoscale electronic devices.3 To date,
† Central China Normal University.
‡ The Hong Kong University of Science and Technology.
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10.1021/om0490637 CCC: $30.25 © 2005 American Chemical Society
Publication on Web 02/25/2005

Heterobimetallic Ferrocene-Ruthenium Complexes
Organometallics, Vol. 24, No. 7, 2005 1453
Scheme 1
optical properties.15 Previously reported examples of
(CH)x-bridged bimetallic complexes are limited to a few
of those with nonbranched (CH)2,16 (CH)4,17,19c (CH)5,18
(CH)6,19 and (CH)820 bridges, and most of them have the
same end groups. Heterobimetallic complexes may have
second-order NLO properties.21 In fact, heterobimetallic
complexes related to (CH)x-bridged bimetallic complexes
such as (CO)3MdC(OCH3)-(CHdCH)n-(C5H4)Fe(C5H5)
(M ) W, Cr, n ) 1-4) have been synthesized, and they
have high â values.22 In this report, the synthesis,
characterization, and electrochemical properties of (CHd
CH)3-bridged heterobimetallic ferrocene-ruthenium com-
plexes will be described.
Results and Discussion
Synthesis of the Complex Fc(CHdCH)2CtCH
(4). The general synthetic route for the preparation of
heterobimetallic polyenes is outlined in Scheme 1. The
ferrocene-containing phosphonium bromide 2 was pre-
pared in four steps: aminomethylation of ferrocene
forms the tertiary amine FcCH2NMe2, methylation of
the tertiary amine forms the quarternary ammonium
FcCH2NMe3+, which reacts with sodium hydroxide to
form the alcohol FcCH2OH,23 and reaction of the alcohol
with triphenylphosphonium hydrobromide produces the
complex FcCH2P+Ph3Br- (2). Complex 2 has been
characterized by NMR and elemental analysis. The 31
P
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NMR spectrum in CDCl3 showed a singlet at 19.79 ppm.
The H NMR spectrum in CDCl3 is much like that of
1
the compound ((1′,2,2′,3,3′,4,4′,5-octamethylferrocenyl)-
methyl)triphenylphosphonium bromide.24
The ferrocenyl-derived triphenylphosphonium bro-
mide 2 underwent a Wittig reaction with the aldehyde
TMS-CtCCHdCHCHO (using NaN(TMS)2 as the base)
to produce the complex FcCHdCHCHdCHCtCSiMe3
(3). This complex was obtained as a mixture of 3E,5E
and 3E,5Z isomers, which can be separated by chroma-
tography on silica gel. It was characterized by 1H NMR,
and its structure has been further confirmed by its
reaction with Bu4NF to give the complex FcCHd
CHCHdCHCtCH (4), which was confirmed by an X-ray
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1454 Organometallics, Vol. 24, No. 7, 2005
Yuan et al.
OAc),26 have also been reported. The homonuclear
bimetallic complexes [RuCl(PhPy)(CO)(PPh3)2]2(µ-(CHd
CH)n) (n ) 3, 4), [RuCl(CO)(PMP)]2(µ-(CHdCH)n) (n )
3, 4),19b,20b and [RuTp(CO)(PPh3)]2(µ-(CHdCH)2-C6H4-
(CHdCH)2)27 were also reported recently.
Crystal Structures of Complexes 4 and 6. The
molecular structure of Fc-CHdCHCHdCHCtCH (4) is
depicted in Figure 1. The crystallographic details and
selected bond distances and angles are given in Tables
1 and 2, respectively. As shown in Figure 1, the
compound contains two trans carbon-carbon double
bonds. The structure displayed an extended conforma-
tion where the C(5)-C(6) double bond and the Cp
remained nearly coplanar, with a maximum deviation
from the least-squares plane of 0.0177 Å for C(6). The
molecular structure of FcCHdCHCHdCHCHdCHRuCl-
(CO)(PMe3)3 (6) is depicted in Figure 2. The crystal-
lographic details and selected bond distances and angles
are given in Tables 3 and 4, respectively. The complex
contains a ferrocenyl moiety with a cyclopentadienyl
ring substituted with a CHdCHCHdCHCHdCH group
linked to a ruthenium center. The ruthenium center is
a distorted octahedron with three meridionally bound
PMe3 ligands. The vinyl group is trans to a PMe3 ligand,
and the CO group is trans to the chloride group, as
suggested by NMR data. The overall geometry around
the ruthenium center is closely related to the bimetallic
ruthenium complex [RuCl(CO)(PMe3)3]2(µ-CHdCHCHd
CHCHdCHCHdCH).20 It is worth noting that the vinyl
groups are essentially coplanar with Cl-Ru-CO. Thus,
Ru(1), Cl(1), C(51) O(1), C(45), and C(46) form a plane
with a maximum deviation from the least-squares plane
of 0.0149 Å for C(45). Such a coplanar phenomenon of
the vinyl group and CO is expected, due to the strong
π-interaction between CO and vinyl with metal centers
in such a conformation.20,31 The (CH)6 unit shows a
single/double alternation pattern of carbon-carbon
bonds. All of the olefinic double bonds are in a trans
geometry. The formal double bonds have an average
bond distance of 1.342 Å, and the formal single bonds
have an average bond distance of 1.455 Å. The difference
between the average single- and double-bond distances
is 0.113 Å. The structural parameters of the (CH)6 chain
are similar to those of [RuCl(CO)(PMe3)3]2(µ-CHd
CHCHdCHCHdCHCHdCH),20 [MoTp*Cl(NO)]2(µ-4,4′-
NC5H4(CHdCH)4C5H4N),32 and PhCHdCH(CHdCH)2-
CHdCHPh.33 In these compounds, the differences in the
average single- and double-bond distances are 0.099,
0.11, and 0.092 Å, respectively.
Figure 1. Molecular structure of Fc-CHdCHCHdCHCt
CH (4).
diffraction study (Figure 1). Treatment of 3 with n-Bu4-
NF in THF produced complex 4, which was isolated as
a red crystalline solid.
Synthesis of Heterobimetallic Complexes. The
complex FcCHdCHCHdCHCtCH (4) reacted with Ru-
HCl(CO)(PPh3)3 to give the insertion product Fc-(CHd
CH)3-RuCl(CO)(PPh3)2 (5), which can be isolated as a
red solid in 80% yield. This compound has been char-
acterized by NMR and elemental analysis. The 31P NMR
spectrum in CD2Cl2 showed a singlet at 30.35 ppm,
which is typical for RuCl((E)-CHdCHR)(CO)(PPh3)2.25a
1
The H NMR spectrum in CD2Cl2 displayed the Ru-
CH signal at 7.94 ppm, the chemical shift of which is
similar to those of the complexes [RuCl(CO)(PPh3)2]2-
(µ-(CHdCH)n) and [RuCl(CO)(PPh3)2]2 (µ-CHdCH-Ar-
CHdCH), and there were three singlet signals of Cp
(C5H5FeC5H4) at 4.01, 4.11, and 4.21 ppm. The five-
coordinated complex 5 is air-sensitive, especially in
solution.
Several related (CHdCH)3-bridged heterobimetallic
six-coordinated complexes were prepared from complex
5. Treatment of 5 with PMe3 produced the six-coordi-
nated complex Fc(CHdCH)3RuCl(CO)(PMe3)3 (6). The
complex is stable in solution and can be purified by
chromatography on silica gel. The PMe3 ligands in 6 are
meridionally coordinated to ruthenium, as indicated by
the AM2 pattern 31P NMR spectrum. The 1H NMR (31P-
decoupled) spectrum in CD2Cl2 displayed the Ru-CH
3
signal at 7.94 ppm with a J(HH) coupling constant of
16.7 Hz. The magnitude of the coupling constant
indicates that the two vinylic protons (Ru-CHdCH) are
in a trans geometry and that the acetylene is cis-
inserted into the Ru-H bond. The structure of 6 has
been confirmed by an X-ray diffraction study (Figure
2).
Reaction of 5 with 4-phenylpyridine (PhPy), 2,6-(Ph2-
PCH2)2C5H3N (PMP), and KTp (Tp ) hydridotris-
(pyrazolyl)borate) give the corresponding six-coordi-
nated complexes Fc(CHdCH)3RuCl(CO)(PhPy)(PPh3)2
(7), Fc(CHdCH)3RuCl(CO)(PMP) (8), and Fc(CHd
CH)3RuTp(CO)(PPh3) (9), respectively. These complexes
have been characterized by NMR spectroscopy and
elemental analysis. The closely related mononuclear
complexes RuCl(CHdCHR)(L)(CO)(PPh3)2 (L ) 2e ni-
trogen donor ligands) have been previously prepared
from the reaction of HCtCR with RuHCl(L)(CO)-
(PPh3)2.25 A few ruthenium PMP complexes, for example
RuCl2(PPh3)(PMP) and RuHX(PPh3)(PMP) (X ) Cl,
Electrochemical Study. The cyclic voltammogram
of complex 6 is shown in Figure 3. As shown in Figure
3, complex 6 exhibited two partially reversible oxidation
waves at 0.37 and 0.51 V vs Ag/AgCl with a scan
(26) (a) Jia, G.; Lee, H. M.; Williams, I. D.; Lau, C. P.; Chem, Y.
Organometallics 1997, 16, 3941. (b) Rahmouni, N.; Osborn, J. A.;
Decian, A.; Fischer, J.; Ezzamarty, A. Organometallics 1998, 17, 2470
and references therein.
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Jia, G. J. Organomet. Chem. 2003, 683, 331.
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Wonchoba, E. R.; Parshall, G. W. Inorg. Synth. 1974, 15, 45.
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(30) Trofimenko, S. Inorg. Synth. 1970, 12, 99.
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17, 3974.
(25) (a) Torres, M. R.; Vegas, A.; Santos, A.; Ros, J. J. Organomet.
Chem. 1986, 309, 169. (b) Santos, A.; Lo´pez, J.; Gala´n, A.; Gonza´lez,
J. J.; Tinono, P.; Echavarren, A. M. Organometallics 1997, 16, 3482.
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Heterobimetallic Ferrocene-Ruthenium Complexes
Organometallics, Vol. 24, No. 7, 2005 1455
Figure 2. Molecular structure of C5H5FeC5H4CHdCHCHdCHCHdCHRuCl(CO)(PMe3)3 (6).
Table 1. Crystallographic Data and Structure
Refinement Details for Complex 4
Table 3. Crystal Data and Structure Refinement
Details for Compound 6
formula
formula wt
cryst syst
space group
a, Å
C
16H14Fe
formula
C
26H43ClFeOP3Ru
262.12
formula wt
656.88
monoclinic
cryst syst
monoclinic
P21/n
P21/c
space group
14.1566(17)
a, Å
13.467(3)
b, Å
c, Å
7.6311(9)
b, Å
14.134(3)
11.8956(14)
c, Å
16.930(3)
R, deg
90
â, deg
112.050(3)
2986.5(10)
4
â, deg
103.094(2)
V, Å3
γ, deg
90
Z
V, Å3
1251.7(3)
dcalcd, g/cm3
1.461
2.18-25.00
14 775
5127 (R(int) ) 0.0394)
5127/6/298
1.053
R1 ) 0.0511, wR2 ) 0.1277
R1 ) 0.0710, wR2 ) 0.1354
0.984 and -0.783
Z
4
θ range, deg
dcalcd, g cm-3
θ range, deg
no. of rflns collected
no. of indep rflns
final R indices (I > 2σ(I))
goodness of fit
largest diff peak, e Å-3
largest diff hole, e Å-3
1.391
no. of rflns collected
no. of indep rflns
no. of data/restraints/params
goodness of fit on F2
final R indices (I > 2σ(I))
R indices (all data)
largest diff peak and hole, e Å-3
2.95-28.27
7539
3012 (R(int) ) 2.26%)
R1 ) 0.0353, wR2 ) 0.0874
1.04
0.286
-0.187
Table 4. Selected Bond Lengths (Å) and Bond
Angles (deg) of Complex 6
Table 2. Selected Bond Lengths (Å) and Bond
Angles (deg) of Complex 4
Bond Lengths (Å)
Bond Lengths
Ru(1)-P(1)
Ru(1)-P(2)
Ru(1)-P(3)
Ru(1)-Cl(1)
Ru(1)-C(51)
Ru(1)-C(46)
2.3772(19)
2.3702(14)
2.3642(15)
2.496(3)
1.792(10)
2.067(8)
C(1)-C(41)
C(41)-C(42)
C(42)-C(43)
C(43)-C(44)
C(44)-C(45)
C(45)-C(46)
1.497(10)
1.360(10)
1.444(10)
1.293(10)
1.424(10)
1.374(12)
C(1)-C(2)
C(2)-C(3)
C(3)-C(4)
C(4)-C(5)
1.171(3)
1.417(3)
1.334(3)
1.436(3)
C(5)-C(6)
C(7)-C(6)
Fe(1)-C(7)
1.322(3)
1.457(3)
2.045(2)
Bond Angles
C(1)-C(2)-C(3)
C(4)-C(3)-C(2)
C(3)-C(4)-C(5)
C(6)-C(5)-C(4)
C(5)-C(6)-C(7)
177.8(2)
123.2(2)
126.1(2)
124.0(2)
127.2(2)
C(8)-C(7)-C(6)
C(11)-C(7)-C(6)
C(8)-C(7)-C(11)
C(9)-C(8)-C(7)
125.76(19)
127.20(19)
107.02(18)
108.8(2)
Bond Angles (deg)
C(51)-Ru(1)-P(1)
C(51)-Ru(1)-P(2)
C(51)-Ru(1)-P(3)
100.2(3)
90.5(3)
88.1(3)
P(2)-Ru(1)-Cl(1)
P(3)-Ru(1)-Cl(1)
P(3)-Ru(1)-P(1)
P(3)-Ru(1)-P(2)
C(42)-C(41)-C(1)
C(41)-C(42)-C(43) 121.0(6)
C(44)-C(43)-C(42) 128.2(7)
C(43)-C(44)-C(45) 133.0(7)
C(46)-C(45)-C(44) 126.9(9)
90.59(7)
90.90(7)
99.80(7)
168.12(5)
121.4(7)
C(51)-Ru(1)-Cl(1) 178.9(3)
C(51)-Ru(1)-C(46)
C(46)-Ru(1)-P(1)
C(46)-Ru(1)-P(2)
C(46)-Ru(1)-P(3)
C(46)-Ru(1)-Cl(1)
P(1)-Ru(1)-Cl(1)
P(2)-Ru(1)-P(1)
93.1(4)
166.5(2)
86.1(2)
82.3(2)
86.9(2)
ranging from 0 to 1.0 V, showing that, at the electrode
surface, the neutral bimetallic complex underwent two
successive one-electron oxidations to yield the mono-
and dication, respectively. Cyclic voltammograms of
related monometallic iron (4) and ruthenium complexes
(RuCl(CO)(PMe3)3((E,Z)-CHdCHCHdCHCCtCH) (10)
and RuCl(CO)(PMe3)3((E)-CHdCHPh) (11)) were mea-
sured under identical conditions. The cyclic voltammo-
gram of iron complex 4 showed only one reversible
oxidation at 0.51 V. The cyclic voltammograms of both
monometallic ruthenium complexes 10 (0.94 V) and 11
(0.97 V) showed one irreversible oxidation peak at a
potential similar to that of the nonconjugated bimetallic
complex [RuCl(CO)(PMe3)3]2(µ-CHdCHCH2CH(OMs)-
CH(OMs)CH2CHdCH), which showed one irreversible
oxidation peak at 1.09 V vs Ag/AgCl. (The ferrocene/
79.80(9) C(45)-C(46)-Ru(1) 131.0(7)
92.06(7) O(1)-C(51)-Ru(1) 176.6(9)
ferrocenium redox couple was located at 0.26 V under
the experimental condition of ref 20.)
The first oxidation wave at 0.37 V in the cyclic
voltammogram of complex 6 is tentatively ascribed to
the ferrocene-ferrocenium couple. Substitution of the
end hydrogen in the iron complex 4 by the ruthenium
end group renders oxidation 0.14 V more favorable. The
second oxidation, which should have more ruthenium
character, is about 0.4 V more favorable than that of
the monometallic ruthenium complexes. This can be

1456 Organometallics, Vol. 24, No. 7, 2005
Yuan et al.
BrPFe: C, 64.36; H, 4.84. Found: C, 63.98; H, 4.70. 31P NMR
1
(160 MHz, CDCl3): δ 19.79 (s). H NMR (400 MHz, CDCl3): δ
1.98 (s, 2H, CH2), 3.97 (s, 2H, C5H2H2CH2), 4.06 (s, 2H, C5H2H2
CH2), 4.36 (s, 5H, C5H5), 7.71 (m, 15H, PPh3).
FcCHdCHCHdCHCtCSiMe3 (3). To a slurry of (ferro-
cenylmethyl)triphenylphosphonium bromide (2; 1.95 g, 3.6
mmol) in THF (40 mL) was added a 2 M THF solution of NaN-
(SiMe3)2 (1.8 mL, 3.6 mmol). The mixture was stirred for 30
min, and then a solution of the aldehyde Me3SiCtCCHd
CHCHO (0.5 g, 3.29 mmol) in THF (20 mL) was added slowly.
The resulting solution was stirred for another 30 min, and then
water (50 mL) was added. The layers were separated, and the
aqueous layer was extracted with diethyl ether (3 × 50 mL).
The combined organic layers were washed with a saturated
aqueous solution of sodium chloride (2 × 20 mL), dried over
MgSO4, filtered, and then concentrated under rotary evapora-
tion. The crude product was purified by column chromatog-
raphy (silica gel, eluted with petroleum ether) to give a red
solid. Yield: 0.38 g, 34%. Anal. Calcd for C19H22SiFe: C, 68.26;
H, 6.63. Found: C, 67.88; H, 6.75. 1H NMR (400 MHz,
CDCl3): δ 0.20 (s, 9H, SiMe3), 4.10 (s, 5H, C5H5Fe), 4.29 (s,
2H, C5H2H2Ct), 4.38 (s, 2H, C5H2H2Ct), 5.58 (d, 1H, J(HH)
) 15.2 Hz, d-CH), 6.42 (m, 2H, a,b-CH), 6.69 (q, 1H, J(HH) )
8.4, 15.2 Hz, c-CH).
FcCHdCHCHdCHCtCH (4). To a solution of complex 3
(0.16 g, 0.5 mmol) in THF (10 mL) was slowly added a 1 M
THF solution of n-Bu4N+F- (0.5 mL, 1 M in THF) with stirring.
After 2 h, the solvent was removed to give a red oil. The crude
product was purified by column chromatography to give red
crystals. Yield: 0.12 g, 96%. Anal. Calcd for C16H14Fe: C,
73.31; H, 5.38. Found: C, 73.10; H, 5.52. 1H NMR (400 MHz,
CDCl3): δ 3.01 (d, J(HH) ) 2.0 Hz, 1H, tCH), 4.04 (s, 5H,
C5H5Fe), 4.23 (s, 2H, FeC5H2H2Cd), 4.32 (s, 2H, FeC5H2H2Cd
), 5.48 (q, J(HH) ) 2.0, 15.6 Hz, 1H, d-CH), 6.35 (m, 2H, a,b-
CH), 6.65 (q, J(HH) ) 8.8, 15.6 Hz, 1H, c-CH). 13C NMR (100
MHz, CDCl3): δ 67.15, 69.34, 69.56, 79.21 (s, C5H5, C5H4),
81.82, 83.72 (s, CtC), 106.84, 125.18, 134.80, 144.06 (s, a,b,c,d-
CH).
Figure 3. Cyclic voltammogram of complex 6.
attributed to the strong electronic communications
between the iron end group and the ruthenium end
group.
Complex 7 showed two partially reverisible oxidation
waves at 0.41 and 0.32 V. Complexes 8 and 9 have only
one oxidation wave at 0.47 and 0.44 V, respectively, with
a scan ranging from 0 to 1.0 V; both of them are
reversible with ∆EP ) 0.07 V. These results show that
changes of the ligands of Ru have a large effect on the
oxidation potentials of the ferrocene moiety. The de-
pendence of the redox potentials of the ferrocene moiety
on the Ru moiety suggests that significant electronic
communication between the ferrocene moiety and the
Ru center occurs via the polyene linker.
Summary. We have successfully prepared bimetallic
complexes bridged by CHdCHCHdCHCHdCH with
different end groups. The structures of FcCHdCHCHd
CHCtCH and FcCHdCHCHdCHCHdCHRuCl(CO)-
(PMe3)3 have been confirmed by X-ray diffraction.
Electrochemical studies have shown that the metals
linked through the CHdCHCHdCHCHdCH bridge
interact with each other.
Experimental Section
FcCHdCHCHdCHCHdCHRuCl(CO)(PPh3)2 (5). To a
suspension of RuHCl(CO)(PPh3)3 (0.80 g, 0.84 mmol) in CH2-
Cl2 (20 mL) was slowly added a solution of 4 (0.26 g, 0.99
mmol) in CH2Cl2 (15 mL). The reaction mixture was stirred
for 30 min to give a red solution. The reaction mixture was
filtered through a column of Celite. The volume of the filtrate
was reduced to ca. 5 mL under vacuum. Addition of hexane
(50 mL) to the residue produced a red solid, which was
collected by filtration, washed with hexane, and dried under
vacuum. Yield: 0.64 g, 80%. Anal. Calcd for C53H45ClOP2-
FeRu: C, 66.85; H, 4.76. Found: C, 67.10; H, 4.57. 31P NMR
All manipulations were carried out at room temperature
under a nitrogen atmosphere using standard Schlenk tech-
niques, unless otherwise stated. Solvents were distilled under
nitrogen from sodium-benzophenone (hexane, diethyl ether,
THF, benzene) or calcium hydride (dichloromethane, CHCl3).
The starting materials RuHCl(CO)(PPh3)3,28 TMS-CtCCHd
CHCHO,20b 1-(hydroxymethyl)ferrocene,23 2,6-(Ph2PCH2)2C5H3N
(PMP),29 and KTp30 were prepared according to literature
methods, and complexes 1019b and 11 were also prepared
according to literature methods. Elemental analyses (C, H, N)
were performed by the Microanalytical Services, College of
Chemistry, CCNU. 1H, 13C, and 31P NMR spectra were col-
lected on a Varian MERCURY Plus 400 spectrometer (400
1
(160 MHz, CD2Cl2): δ 30.35 (s). H NMR (400 MHz, CD2Cl2):
δ 4.01 (s, 5H, C5H5), 4.11 (s, 2H, C5H2H2Cd), 4.21 (s, 2H,
C5H2H2Cd), 5.45 (m, 1H, d-CH), 5.91 (q, J(HH) ) 10.8, 14.2
Hz, 1H, c-CH), 6.02 (d, J(HH) ) 15.6 Hz, 1H, f-CH), 6.18 (q,
J(HH) ) 10.8, 15.4 Hz, 1H, e-CH), 7.35 (m, 31H, b-CH, PPh3),
7.92 (d, J(HH) ) 12.4 Hz, 1H, Ru-H).
1
MHz). H and 13C NMR chemical shifts are relative to TMS,
and 31P NMR chemical shifts are relative to 85% H3PO4.
The electrochemical measurements were performed on an
Autolab PGSTAT 30 instrument. A three-component electro-
chemical cell was used with a glassy-carbon electrode as the
working electrode, a platinum wire as the counter electrode,
and a Ag/AgCl electrode as the reference electrode. The cyclic
voltammograms were collected with a scan rate ranging from
50 to 200 mV/s in CH2Cl2 containing 0.10 M n-Bu4NClO4 as
the supporting electrolyte. The peak potentials reported were
referenced to Ag/AgCl. The ferrocene/ferrocenium redox couple
was located at 0.49 V under our experimental conditions.
FcCH2P+Ph3Br- (2). A mixture of 1-(hydroxymethyl)-
ferrocene (0.85 g, 3.96 mmol) and triphenylphosphonium
hydrobromide (1.36 g, 3.96 mmol) in 120 mL of toluene was
refluxed for 2 h until separation from the eutectic condensate
was completed in a Dean-Stark trap. After cooling, a yellow
solid precipitated, which was filtered off, washed with 20 mL
of ether, and dried. Yield: 2.02 g, 94%. Anal. Calcd for C29H26-
FcCHdCHCHdCHCHdCHRuCl(CO)(PMe3)3 (6). To a
solution of complex 5 (0.18 g, 0.19 mmol) in CH2Cl2 (30 mL)
was added a 1 M THF solution of PMe3 (2.0 mL, 2.0 mmol).
The reaction mixture was stirred overnight. The solvent of the
reaction mixture was removed under vacuum. The residue was
purified by column chromatography (silica gel, eluted with 20/
80 acetone/petroleum ether) to give a red solid. Yield: 0.93 g,
79%. Anal. Calcd for C26H42ClOP3FeRu: C, 47.61; H, 6.45.
Found: C, 47.65; H, 6.51. 31P NMR (160 MHz, CD2Cl2): δ
1
-19.42 (t, J(PP) ) 24.2 Hz), -7.89 (d, J(PP) ) 24.2 Hz). H
NMR (400 MHz, CD2Cl2): δ 1.28 (t, J(PH) ) 3.4 Hz, 18H,
PMe3), 1.35 (d, J(PH) ) 6.8 Hz, 9H, PMe3), 4.04 (s, 5H, C5H5),
4.11 (s, 2H, C5H2H2Cd), 4.25 (s, 2H, C5H2H2Cd), 5.79 (q,
J(HH) ) 10.8, 14.4 Hz, 1H, d-CH), 6.04 (d, J(HH) ) 15.6 Hz,
1H, f-CH), 6.14 (q, J(HH) ) 10.4, 14.4 Hz, 1H, c-CH), 6.30 (m,
2H, b,e-CH), 7.94 (m, 1H, a-CH). 13C NMR (100 MHz, CDCl3):

Heterobimetallic Ferrocene-Ruthenium Complexes
Organometallics, Vol. 24, No. 7, 2005 1457
δ 16.79 (t, J(PC) ) 15.3 Hz, PMe3), 20.03 (d, J(PC) ) 21.0 Hz,
PMe3), 66.57, 68.83, 69.46, 85.29 (s, C5H5, C5H4), 122.78,
126.33, 129.31, 137.93 (s, b,c,d,e,f-CH), 176.24 (Ru-CH),
202.81 (CO).
Crystals suitable for X-ray diffraction were grown from a
hexane solution cooled to -20 °C. A crystal was mounted on a
glass fiber, and the diffraction intensity data were collected
on a Bruker CCD 4K diffractometer with graphite-monochro-
mated Mï KR radiation (λ ) 0.710 73 Å). Lattice determination
and data collection were carried out using SMART version
5.625 software. Data reduction and absorption corrections were
performed using SAINT version 6.45 and SADABS version
2.03. Structure solution and refinement were performed using
the SHELXTL version 6.14 software package. All non-
hydrogen atoms were refined anisotropically. All hydrogens
were included in their idealized positions and refined using a
riding model. Further crystallographic details were sum-
marized in Table 1, and selected bond distances and angles
are given in Table 2.
Crystallographic Analysis for Fc(CHdCH)3RuCl(CO)-
(PMe3)3 (6). Crystals suitable for X-ray diffraction were grown
from a benzene solution layered with hexane. A red bar-shaped
crystal of C5H5FeC5H4CHdCHCHdCHCHdCHRuCl(CO)-
(PMe3)3 (6), with dimensions 0.30 × 0.15 × 0.10 mm3, was
mounted on a glass fiber, and diffraction intensity data were
collected by a Bruker Apex CCD diffractometer with graphite-
monochromated Mo KR radiation (λ ) 0.710 73 Å) at 100(2)
K. Lattice determination and data collection were carried out
using SMART version 5.625 software. Data reduction and
absorption correction were performed using SAINT version
6.26 and SADABS version 2.03. Structure solution and refine-
ment were performed using SHELXTL version 6.10 software
package. All non-hydrogen atoms (except for those disordered
atoms) were refined anisotropically. Further crystallographic
details are given in Table 3, and selected bond distances and
angles are given in Table 4.
FcCHdCHCHdCHCHdCHRuCl(CO)(PhPy)(PPh3)2 (7).
A mixture of complex 5 (0.18 g, 0.19 mmol) and 4-phenylpy-
ridine (0.06 g, 0.38 mmol) in CH2Cl2 (20 mL) was stirred for
30 min. The solution was filtered through a column of Celite.
The volume of the filtrate was reduced to ca. 2 mL under
vacuum. Addition of hexane (15 mL) to the residue produced
a red solid, which was collected by filtration, washed with
hexane, and dried under vacuum. Yield: 0.18 g, 85%. Anal.
Calcd for C64H54ClNOP2FeRu: C, 69.41; H, 4.92. Found: C,
1
69.81; H, 4.75. 31P NMR (160 MHz, CD2Cl2): δ 26.14 (s). H
NMR (400 MHz, CD2Cl2): δ 4.06 (s, 5H, C5H5), 4.19 (s, 2H,
C5H2H2Cd), 4.30 (s, 2H, C5H2H2Cd), 5.50 (q, J(HH) ) 11.0,
14.6 Hz, 1H, d-CH), 5.68 (q, J(HH) ) 10.0, 16.0 Hz, 1H, c-CH),
6.07 (m, 1H, f-CH), 6.31 (q, J(HH) ) 11.0, 15.2 Hz, 1H, e-CH),
6.77 (br, 2H, C5H2H2N), 7.40 (m, 36H, Ph, b-CH), 8.43 (br d,
J(HH) ) 15.6 Hz, 3H, Ru-CH, C5H2H2N).
FcCHdCHCHdCHCHdCHRuCl(CO)(PMP) (8). A mix-
ture of complex 5 (0.18 g, 0.19 mmol) and PMP (0.09 g, 0.19
mmol) in CH2Cl2 (20 mL) was stirred for 15 h. The solution
was filtered through a column of Celite. The volumn of the
filtrate was reduced to ca. 2 mL under vacuum. Addition of
hexane (20 mL) to the residue produced a yellow solid, which
was collected by filtration, washed with hexane, and dried
under vacuum. Yield: 0.14 g, 86%. Anal. Calcd for C48H42-
ClNOP2FeRu: C, 63.83; H, 4.69. Found: C, 64.16; H, 4.43. 31
P
NMR (160 MHz, CD2Cl2): δ 49.83 (s). 1H NMR (400 MHz, CD2-
Cl2): δ 3.95 (s, 5H, C5H5), 4.06 (s, 2H, C5H2H2Cd), 4.13 (m,
4H, C5H2H2Cd, CHH(C5H3N)CHH), 4.49 (m, 2H, CHH(C5H3N)-
CHH), 5.05 (m, 1H, d-CH), 5.28 (m, 1H, c-CH), 5.85 (m, 1H,
f-CH,), 6.16 (m, 1H, e-CH), 7.27-8.78 (m, 25H, Ph, C5H3N,
Ru-CH, b-CH).
Acknowledgment. We acknowledge financial sup-
port from the National Natural Science Foundation of
China (Nos. 20242010 and 20472023), the Scientific
Research Foundation for the Returned Overseas Chi-
nese Scholars, State Education Ministry, and the Na-
tional Key Project for Basic Research of China (No.
2004CCA00100).
FcCHdCHCHdCHCHdCHRuTp(CO)(PPh3) (9). A mix-
ture of complex 5 (0.18 g, 0.19 mmol) and KTp (0.18 g, 0.21
mmol) in CH2Cl2 (20 mL) was stirred for 2 h. The solution was
filtered through a column of Celite to remove the KCl. The
volume of the filtrate was reduced to ca. 2 mL under vacuum.
Addition of hexane (20 mL) to the residue produced a red solid,
which was collected by filtration, washed with hexane, and
dried over vacuum. Yield: 0.14 g, 85%. Anal. Calcd for C44H40-
Supporting Information Available: CIF files giving
crystallographic data for C5H5FeC5H4CHdCHCHdCHCtCH
(4) and C5H5FeC5H4CHdCHCHdCHCHdCHRuCl(CO)(PMe3)3
(6). This material is available free of charge via the Internet
at http://pubs.acs.org.
BN6OPFeRu: C, 60.92; H, 4.65. Found: C, 61.26; H, 4.88. 31
P
NMR (160 MHz, CD2Cl2): δ 49.23 (s). 1H NMR (400 MHz, CD2-
Cl2): δ 4.01 (s, 5H, C5H5), 4.11 (s, 2H, C5H2H2Cd), 5.23 (s,
2H, C5H2H2Cd), 5.67 (m, 1H, d-CH), 5.88-7.73 (m, 30H, PPh3,
Ru-CH, b,c,e,f-CH, Tp).
Crystallographic Analysis for Fc(CHdCH)2CtCH (4).
OM0490637