Synthesis and photochemistry of ring-coupled heterobimetallic compounds of ruthenium

Article abstract of DOI:10.1016/S0020-1693(99)00588-5

Reaction of the versatile reagent Ru(CO)₂(μ-η⁵,η¹-C₅H₄CR₂C₅H₄), where R = H or CH₃, with M(CO)₆ or M(CO)₃(CH₃CN)₃, where M = Mo or W, yields bimetallic compounds of the form RuM(CO)₅(μ-η⁵,η⁵-C₅H₄CR₂C₅H₄) in excellent yield, while reaction with Fe(CO)₅ yields RuFe(CO)₂(μ-CO)₂[μ-η⁵,η⁵-C₅H₄C(CH₃)₂C₅H₄] in excellent yield. Reaction with Ni(CO)₄ yields thermally unstable RuNi(CO)₃[μ-η⁵,η⁵-C₅H₄C(CH₃)₂C₅H₄]. These compounds have been characterized by IR and NMR spectroscopies, and, with the exception of the Ru/Ni compound, elemental analysis. Photolysis of RuMo(CO)₅[μ-η⁵,η⁵-C₅H₄C(CH₃)₂C₅H₄] in the presence of triphenylphosphine yields both of the simple mono-carbonyl substitution products with the phosphine on Ru and Mo. Photolysis of the derivative with phosphine bound to the molybdenum yields [Ru(σ-C₆H₅)-(CO)][Mo(CO)₂][μ-P(C₆H₅)₂](μ-η⁵,η⁵-C₅H₄C(CH₃) ₂C₅H₄)[Ru-Mo]. Photolysis of RuFe(CO)₂(μ-CO)₂[μ-η⁵,η⁵-C₅H₄C(CH₃)₂C₅H] with triphenylphosphine yields [Ru(CO)]{Fe[P(C₆H₅)₃]}(μ-η⁵,η⁵-C₅H₄C(CH₃)₂C₅H₄][Ru-Fe]. Photolysis of the Ru/Mo and Ru/W heterobimetallic compounds in deuterobenzene established that two metal-hydride species were formed, one whose chemical shift was characteristic of a CpRu(CO)₂H and the second typical of a CpM(CO)₃H. Photolysis of the Ru/Mo and Ru/W compounds in 20% chloroform in benzene followed by chromatography of the reaction mixtures permitted isolation of the isomeric photoproducts as their chloride derivatives. IR and NMR spectroscopy and X-ray crystallography of these compounds established them to have 'twist' structures in which one cyclopentadienyl ring is η¹ to one of the metals and η⁵ to the second. The molecular structures of four compounds were determined: RuMo(CO)₅[μ-η⁵,η⁵-C₅H₄C(CH₃)₂C₅H₄]: monoclinic, P2₁/n, a = 9.608(3), b = 12.613(4), c = 14.467(5) A?, β = 97.59(2)°, V = 1738.0(9) A?³, z=4, R(F) = 3.53. RuW(CO)₅(μ-η⁵,η⁵-C₅H₄CH₂C₅H₄): monoclinic, P2₁/c, a= 14.232(5), b= 7.833(3), c= 13.771(5) A?, β = 93.22(3)°, V = 1533(1) A?³, z=4, R(F) = 3.88. [Mo(CO)₃][Ru(CO)₂Cl](μ-η⁵,η¹:η⁵-C₅H₄CH₂C₅H₃): monoclinic, P2₁/c, a = 10.259(9), b = 12.666(5), c = 13.451(5(5) A?, β = 109.85(4)°, V = 1641(1) A?³, z = 4, R(F) = 2.72. [Ru(CO)₂][W(CO)₃Cl](μ-η⁵,η¹:η⁵-C₅H₄CH₂C₅H₃): monoclinic, P2₁/c, a = 12.793(3), b = 9.485(2), c = 13.450(2) A?, β = 94.56(1)°, V= 1626.8(6) A?³, z = 4, R(F) = 3.67. (C) 2000 Elsevier Science S.A.

Full text of DOI:10.1016/S0020-1693(99)00588-5

www.elsevier.nl/locate/ica
Inorganica Chimica Acta 300–302 (2000) 800–809
Synthesis and photochemistry of ring-coupled heterobimetallic
compounds of ruthenium. The molecular structures of
RuM(CO)5(m-h5,h5-C5H4CR2C5H4), where M=Mo, R=CH3;
M=W, R=H, [Ru(CO)2][Mo(CO)3Cl](m-h5,h1:h5-C5H4CH2C5H3)
and [W(CO)3][Ru(CO)2Cl](m-h5,h1:h5-C5H4CH2C5H3)
Thomas E. Bitterwolf a,*, Abdul A. Saygh a, Joyce E. Shade b, Arnold L. Rheingold c,
Glenn P.A. Yap c, Louise M. Lable-Sands c
a Department of Chemistry, Uni6ersity of Idaho, Moscow, ID 83844-2343, USA
b Department of Chemistry, US Na6al Academy, Annapolis, MD 21402, USA
c Department of Chemistry, Uni6ersity of Delaware, Newark, DE 19716, USA
Received 19 November 1999
Abstract
Reaction of the versatile reagent Ru(CO)2(m-h5,h1-C5H4CR2C5H4), where R=H or CH3, with M(CO)6 or M(CO)3(CH3CN)3,
where M=Mo or W, yields bimetallic compounds of the form RuM(CO)5(m-h5,h5-C5H4CR2C5H4) in excellent yield, while
reaction with Fe(CO)5 yields RuFe(CO)2(m-CO)2[m-h5,h5-C5H4C(CH3)2C5H4] in excellent yield. Reaction with Ni(CO)4 yields
thermally unstable RuNi(CO)3[m-h5,h5-C5H4C(CH3)2C5H4]. These compounds have been characterized by IR and NMR spectro-
scopies, and, with the exception of the Ru/Ni compound, elemental analysis. Photolysis of RuMo(CO)5[m-h5,h5-
C5H4C(CH3)2C5H4] in the presence of triphenylphosphine yields both of the simple mono-carbonyl substitution products with the
phosphine on Ru and Mo. Photolysis of the derivative with phosphine bound to the molybdenum yields [Ru(s-C6H5)-
(CO)][Mo(CO)2][m-P(C6H5)2](m-h5,h5-C5H4C(CH3)2C5H4)[Ru–Mo]. Photolysis of RuFe(CO)2(m-CO)2[m-h5,h5-C5H4C(CH3)2C5H4]
with triphenylphosphine yields [Ru(CO)]{Fe[P(C6H5)3]}(m-CO)2[m-h5,h5-C5H4C(CH3)2C5H4][Ru–Fe]. Photolysis of the Ru/Mo
and Ru/W heterobimetallic compounds in deuterobenzene established that two metal-hydride species were formed, one whose
chemical shift was characteristic of a CpRu(CO)2H and the second typical of a CpM(CO)3H. Photolysis of the Ru/Mo and Ru/W
compounds in 20% chloroform in benzene followed by chromatography of the reaction mixtures permitted isolation of the
isomeric photoproducts as their chloride derivatives. IR and NMR spectroscopy and X-ray crystallography of these compounds
established them to have ‘twist’ structures in which one cyclopentadienyl ring is h1 to one of the metals and h5 to the second. The
molecular structures of four compounds were determined: RuMo(CO)5[m-h5,h5-C5H4C(CH3)2C5H4]: monoclinic, P21/n, a=
3
5
5
,
,
9.608(3), b=12.613(4), c=14.467(5) A, i=97.59(2)°, V=1738.0(9) A , z=4, RF=3.53. RuW(CO)5(m-h ,h -C5H4CH2C5H4):
3
,
,
monoclinic, P21/c, a=14.232(5), b=7.833(3), c=13.771(5) A, i=93.22(3)°, V=1533(1) A , z=4, RF=3.88.
[Mo(CO)3][Ru(CO)2Cl](m-h ,h :h -C5H4CH2C5H3): monoclinic, P21/c, a=10.259(9), b=12.666(5), c=13.451(5(5) A, i=
109.85(4)°, V=1641(1) A , z=4, RF=2.72. [Ru(CO)2][W(CO)3Cl](m-h ,h :h -C5H4CH2C5H3): monoclinic, P21/c, a=12.793(3),
b=9.485(2), c=13.450(2) A, i=94.56(1)°, V=1626.8(6) A , z=4, RF=3.67. © 2000 Elsevier Science S.A. All rights reserved.
Keywords: Heterobimettallic compounds; Ruthenium complexes; Molecular structures; Photochemistry
5
1
5
,
3
5
1
5
,
3
,
,
1. Introduction
* Corresponding author. Tel.: +1-208-885 6361; fax: +1-208-885
6173.
E-mail address: bitterte@uidaho.edu (T.E. Bitterwolf)
Interest in the synthesis and chemistry of hetero-
bimetallic compounds continues to increase due to a
0020-1693/00/$ - see front matter © 2000 Elsevier Science S.A. All rights reserved.
PII: S0020-1693(99)00588-5

T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
801
We have recently described the synthesis of
Ru(CO)2(m-h5,h1-C5H4CR2C5H4), where R=H (1) or
CH3 (2), which shares with the compound reported by
Green the stabilization of a pendant ring by partial
metal complexation [12]. Reaction of these compounds
with M(CO)6 or M(CO)3(CH3CN)3, where M=Mo or
W, yields the heterobimetallic compounds RuM(CO)5-
(m-h5,h5-C5H4CH2C5H4), where M=Mo (3) or W (4),
and RuMo(CO)5[m-h5,h5-C5H4C(CH3)2C5H4] (5). Simi-
larly, reaction with Fe(CO)5 or Ni(CO)4 yields the
widely held belief in the potential for these compounds
to exhibit metal cooperativity leading to reaction path-
ways not otherwise available to mononuclear or homo-
bimetallic compounds. Our work has dealt in large
measure with the synthesis of bis(cyclopentadienyl-
metal) compounds in which the two cyclopentadienyl
rings are coupled by a carbon or silicon linkage. While
there are many examples of homobimetallic compounds
in this class, the synthesis of heterobimetallic com-
pounds has proven to be more challenging.
Vollhardt and Weldman [1] reported the synthesis of
MoRu(CO)5(m-h5,h5-C5H4C5H4) in greater than statis-
tical yield by reaction of Mo(CO)6, Ru3(CO)12, and
dihydrofulvalene in glyme. Separation of the resultant
mixture of Mo2, Ru2 and MoRu compounds was
achieved by preparative HPLC. Huffman [2] attempted
to develop a more rational route to these compounds
beginning with Mo(CO)2(PMe3)2(h4-C5H4C5H4) with
partial success. Far better results were achieved via the
synthesis of M(CO)3CH3(h5-C5H4C5H5), where M=
Mo or W, in which the pendant cyclopentadiene ring
could be deprotonated and metallated [3]. Vollhardt
and coworkers have developed a substantial chemistry
of the W/Ru and Mo/Ru compound including
acetylene exchange for carbonyl groups [4] and electro-
chemistry [5].
compounds
RuM(CO)n[m-h5,h5-C5H4C(CH3)2C5H4],
where M=Fe, n=4 (6) and M=Ni, n=3 (7). The
characterization and photochemistry of these com-
pounds is reported in this paper.
2. Results and discussion
2.1. Synthesis and characterization of
RuM(CO)n(v-p5,p5-C5H4CR2C5H4)
Compounds 1 and 2 were prepared as previously
reported by reaction of [Cl2Ru(CO)3]2 with 1 equiv. of
CR2(C5H4Tl)2 in refluxing benzene [12]. Compounds 1
and 2 are isolated by chromatography from the reac-
Heterobimetallic derivatives of bis(cyclopentadienyl)-
methane have been reported by Ha¨rter and Werner and
their coworkers. Werner et al. found that it was possi-
ble to selectively prepare (MC5H4CH2C5H5), where
M=Li and Na, then react this species with Group
IX metal carbonyl halides to give M(CO)2(h5-
C5H4CH2C5H5) [6]. Subsequent deprotonation of the
pendant cyclopentadiene ring followed by metallation
yielded heterobimetallic derivatives. Ha¨rter et al. [7]
adapted a reaction reported by Mueller-Westerhoff and
coworkers [8] in which ring lithiated cyclopentadienyl
metal derivatives may be reacted with dimethylamino-
fulvene to yield fulvalene substituted compounds. Re-
duction of the fulvene yields a pendant cyclopenta-
dienyl anion that may be metallated. Heck and Ko¨rnich
have prepared unusual heterobimetallic compounds
having the cyclopentadienyl and tetramethylcyclopenta-
dienyl rings coupled by a ketone carbonyl. Of immedi-
ate relevance to the current work are the compounds
WM(CO)5(m-h5,h5-C5H4–C(=O)–C5Me4), where M=
Fe and Ru [9].
tion mixtures as air-stable, waxy solids in good yields.
Reaction of these compounds with M(CO)6 or
M(CO)3(CH3CN)3, where M=Mo or W, gave the re-
sulting heterobimetallic compounds 3, 4, and 5 in excel-
lent yield after chromatography.
Green and coworkers have described the formation
of heterobimetallic compounds of (2,2-cyclopentadi-
enyl)(indenyl)propane by reaction of ClMn(CO)5 and
[ClRh(CO)2]2 with ZrCl(h5-C5H5)[h5,h2-C5H4C(CH3)2-
C9H6] [10]. In this case, the pendant indenyl group is
stabilized by a dihapto bond to the zirconium.
The compounds are isolated as red to orange–red,
air-stable, crystalline solids. IR spectra of 3 and 5 in
dichloromethane contain two strong carbonyl bands at
Salzer and coworkers have reported the synthesis of
(h5-C5Me4Et)Mo(CO)5Ru(h5-C5H5) [11].

802
T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
2020, 1957 cm−1, and medium intensity bands at 1900
and 1873 cm−1. RuMo(CO)5(m-h5,h5-C5H4C5H4) is re-
ported to have carbonyl stretching bands at 2020, 1942,
1935, 1868 cm−1. Compound 4 has a similar pattern
with two strong bands at 2019 and 1955 cm−1, and
medium bands at 1973, 1889, and 1867 cm−1. It is
likely that the C1 symmetry of the solid state (vide
infra) of compounds 3, 4, and 5 is preserved on the IR
whereas the carbonyl resonances of 4 are almost at
coalesence at r.t. Those resonances are completely aver-
aged at 325 K. A low temperature NMR of 5 (197 K)
failed to freeze out the carbonyl averaging. Averaging
of the carbonyl resonances has been observed for
the Ru, Mo, and W homobimetallic derivatives of
bis(cyclopentadienyl)methane and 2,2-bis(cyclopenta-
dienyl)propane.
The molecular structures of 4 and 5 were determined
by X-ray crystallography of crystals grown from
dichloromethane/petroleum ether by vapor diffusion
and are presented in Figs. 1 and 2. Crystallographic
data for these compounds are summarized in Table 1.
Representative bond length and bond angle data are
presented in Tables 2 and 3. As noted previously, the
molecules have C1 symmetry with the carbonyl groups
on the Ru(CO)2 and M(CO)3 units twisted in opposite
directions. The Ru–Mo and Ru–W bond lengths of
1
time scale in the solution phase. The H NMR spectra
of the three heterobimetallic compounds are simple
with four ring resonances and singlets for the CH2 or
C(CH3)2 bridges. The 13C NMR spectra are also simple
with four ring resonances and two ipso ring carbons
located. In light of the low symmetry suggested by the
IR spectrum and solid state structures, it is likely that
the molecules are rapidly twisting about an axis that
passes through the bridge carbon and the center of the
M–M% bond. Similar averaging has been observed for
M2(CO)6(m-h5,h5-C5H4CR2C5H4), where M=Mo or
W, and R=H or CH3, for which the molecules possess
C2 symmetry in the solid state. The carbonyl resonances
of 3 and 5 are fully averaged at room temperature (r.t),
,
2.9586(1) and 2.970(1) A, respectively, are almost the
exact average of the Ru–Ru, Mo–Mo and W–W bond
lengths in the analogous ring-coupled homobimetallic
,
complexes [13,14]. A W–Ru bond length of 2.978 (2) A
was reported by Heck and Ko¨rnish for their ketone
derivative [9]. Similarly, the ligand bond lengths and
angles are very similar to the homobimetallic com-
pounds. In our experience, the M–M bond lengths of
the bis(cyclopentadienyl)methane derivatives of molyb-
denum and tungsten tend to be slightly shorter than the
corresponding M2(CO)6(h5-C5H5)2 compounds. The
molecular structure of (h5-C5Me4Et)Mo(CO)5Ru(h5-
C5H5) was not reported and the analogous Ru–W
compound without ring coupling is not known.
Reaction of 2 with Fe(CO)5 in refluxing xylene re-
sulted in formation of 6 in essentially quantitative yield.
The IR spectrum of 6 has strong carbonyl stretching
bands at 1995, 1956, 1777 cm−1 and a weak shoulder
at about 1810 cm−1
.
Fig. 1. Molecular structure of 4.
The bands at 1777 and 1810 cm−1 are assigned to
the asymmetric and symmetric stretching modes of the
bridging carbonyls. These are very similar in position to
the bands reported for RuFe(CO)2(m-CO)2(h5-C5H5)2
1
[15]. The H and 13C NMR spectra of 6 are simple with
two sets of two ring resonances and a singlet for the
bridging C(CH3)2 group. Metal carbonyl resonances are
fully averaged at r.t., consistent with the behavior of
Fig. 2. Molecular structure of 5.

T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
803
Table 1
Crystallographic data for 4, 5, 13, and 14
Formula
C18H14MoO5Ru
C16H10O5RuW
C16H9ClMoO5Ru
C17H12ClO5RuW
Crystal parameters
Formula weight
Crystal system
Space group
507.3
monoclinic
P21/n
567.2
monoclinic
P21/c
513.7
monoclinic
P21/c
616.6
monoclinic
P21/c
,
a (A)
9.608(3)
12.613(4)
14.467(5)
97.59(2)
1738.0(9)
4
14.232(5)
7.833(3)
13.771(5)
93.22(3)
1533(1)
4
10.259(9)
12.666(5)
13.451(5)
109.85(4)
1641(1)
4
12.793(3)
9.485(2)
13.450(2)
94.56(1)
1626.8(6)
4
,
b (A)
,
c (A)
i (°)
V (A )
3
,
Z
Crystal dimensions (mm)
Crystal color
0.34×0.38×0.40
red
1.939
16.15
2982
0.32×0.34×0.38
red
2.458
85.06
298
0.23×0.25×0.30
red
2.079
18.70
244
0.38×0.39×0.40
yellow
2.498
81.20
298
Dcalc (g cm−3
)
v(Mo Ka) (cm−1
Temperature (K)
)
Tmax/Tmin
1.29
1.69
1.43
1.89
Data collection
Diffractometer
Monochromator
Radiation
2q Scan range
Data collected (h, k, l)
Reflections collected
Siemens P4
graphite
Mo Ka (u=0.71073 A)
4.0–57.0
912, +16, +19
4562
,
4.0–62.0
920, +11, +19
4982
4.0–50.0
911, +15, +15
3009
4.0–52.0
915, +11, +16
3371
Independent reflections
Independent reflections (Fo]n|(Fo)
Standard/reflections
4401
3498 (n=4)
3/197
4795
3463 (n=5)
3/197
2876
2600 (n=4)
3/197
3225
2406 (n=4)
3/197
Variation in standards (%)
B1
B1
B1
B1
Refinementa
RF (%)
RwF (%)
3.53
4.54
0.002
1.03
15.5
1.0
3.88
5.35
0.002
1.18
16.6
1.0
2.72
4.53
0.011
0.52
11.9
1.2
3.67
3.68
0.004
1.11
11.1
1.1
Z/|max
Z/(z) (e A
No/Nv
−3
,
)
Goodness-of-fit
a Quantity minimized=ꢀwZ2; R=ꢀZ/ꢀ(Fo); Rw=ꢀZw0.5/ꢀ(Fo·w0.5), Z=ꢁ(Fo−Fc)ꢁ.
1
the corresponding homobimetallic compounds. Ring
and carbon resonances were assigned by COSY and
1H/13C correlation spectroscopy. We are not able to
establish to which metal the rings were attached.
Reaction of 2 with Ni(CO)4 in xylene, followed by
chromatography of the reaction mixture on alumina,
resulted in isolation of 7 as a red–brown solid. Over
time this compound decomposes to 2 and an unknown
nickel containing product. Compound 7 has a strong
carbonyl stretching band at 2017 cm−1 and a pair of
The H and 13C NMR spectra are consistent with a
molecule with Cs symmetry. A broad feature was ob-
Table 2
,
Bond lengths (A) and angles (°) for 4
Bond lengths
Ru–W
2.970(1)
1.862(9)
1.878(8)
1.977(8)
1.963(8)
1.962(8)
C(12)–O(12)
C(13)–O(13)
C(14)–O(14)
C(15)–O(15)
C(16)–O(16)
1.147(11)
1.117(11)
1.146(11)
1.157(11)
1.169(11)
Ru–C(12)
Ru–C(13)
W–C(14)
W–C(15)
W–C(16)
medium intensity bands at 1960 and 1943 cm−1
.
Bond angles
W–Ru–C(12)
Ru–W–C(14)
Ru–W–C(16)
C(14)–W–C(15)
C(15)–W–C(16)
Ru–C(13)–O(13)
W–C(15)–O(15)
91.6(3)
70.1(2)
77.4(2)
79.4(3)
80.4(3)
175.7(8)
176.9(8)
W–Ru–C(13)
Ru–W–C(15)
90.4(3)
137.9(2)
91.3(4)
100.3(3)
179.2(6)
173.8(7)
175.4(7)
C(12)–Ru–C(13)
C(14)–W–C(16)
Ru–C(12)–O(12)
W–C(14)–O(14)
W–C(16)–O(16)

804
T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
Table 3
spectrum of 8 has a single resonance at 77.22 ppm. The
analogous homobimetallic compounds, Mo2(CO)6−
n(PPh3)n(m-h5,h5-C5H4CH2C5H4), where n=1 or 2,
have metal carbonyl resonances in the 234 ppm region
and phosphine resonance at about 75 ppm [17], thus we
believe that the triphenylphosphine resides on the
molybdenum atom in 8.
,
Bond lengths (A) and angles (°) for 5
Bond lengths
Ru–Mo
2.958(1)
1.876(6)
1.873(5)
1.977(5)
1.956(5)
1.966(4)
C(12)–O(11)
C(13)–O(13)
C(14)–O(14)
C(15)–O(15)
C(16)–O(16)
1.144(7)
1.131(7)
1.143(6)
1.149(7)
1.159(6)
Ru–C(12)
Ru–C(13)
W–C(14)
W–C(15)
W–C(16)
The IR spectrum of 8 contains bands at 1992, 1933,
1877, and 1814 cm−1 while that of 9 has bands at 1949,
Bond angles
1
1909, 1852, and 1734 cm−1. Like 8, the H and 13C
Mo–Ru–C(12)
Ru–Mo–C(14)
Ru–Mo–C(16)
C(14)–Mo–C(15)
C(15)–Mo–C(16)
Ru–C(13)–O(13)
Mo–C(15)–O(15)
86.7(2)
76.9(1)
72.2(1)
78.1(2)
79.4(2)
177.7(5)
177.0(5)
Mo–Ru–C(13)
Ru–Mo–C(15)
94.7(2)
138.6(2)
92.3(2)
NMR spectra of 9 require either a Cs symmetry or
averaging on the NMR time scale. Two sets of metal
carbonyl resonances are observed at 239.5 and 238.1
ppm with the higher field resonance split by the phos-
phine. A singlet at 48.5 ppm was observed in the 31P
NMR spectrum which is characteristic of a ruthenium
bound triphenylphosphine (vide infra). Coupling be-
tween the phosphine and the ring protons of one ring
C(12)–Ru–C(13)
C(14)–Mo–C(16)
Ru–C(12)–O(11)
Mo–C(14)–O(14)
Mo–C(16)–O(16)
98.1(2)
176.2(5)
175.5(5)
174.9(4)
served at 201 ppm in the 13C spectrum which may be
due to averaging metal carbonyl groups. Stone and
coworkers have reported the synthesis of what was
believed to be RuNi(CO)3(h5-C5H5)2 by reaction of
Ru3(CO)12 and nickelocene [16]. The compound was
too unstable for isolation and decomposed during
work-up to give Ru2(CO)4(h5-C5H5)2 and Ni2(CO)2(h5-
C5H5)2. IR bands attributable to the Ru/Ni compound
were found at 2005 and 1822 cm−1. We shall continue
to examine the chemistry of the ring-coupled Ru/Ni
compounds in the hope of developing a derivative
chemistry of this unique material.
1
allowed complete ring assignments to be made. A H/
13C correlation spectrum permitted the ring carbons to
be assigned to the two rings.
The spectral data suggest that the triphenyl phos-
phine unit is bound to the molybdenum in compound 8
and to the ruthenium in compound 9. The IR data are
consistent with structures in which there is a semibridg-
ing carbonyl in 8 and a bridging carbonyl group in 9.
Photolysis of 8 results in formation of a new product,
10, that may be separated by chromatography. Com-
pound 10 is isolated as an intensely purple oil. Small
amounts of this compound are also isolated from the
synthesis of 8 and 9.
2.2. Solution photolyses with triphenylphosphine
Photolysis of 5 in benzene with an equivalent of
triphenylphosphine followed by chromatographic sepa-
ration was found to yield three products, 8, 9, and 10.
Two of these products, 8 and 9, were established by
spectral analysis and elemental analysis to be isomeric
carbonyl exchange products, while the third, 10, was
shown independently to arise from secondary photo-
lysis of 8.
The 1H spectrum of 10 is complex with separate
resonances for the three phenyl groups, and seven
resonances (one overlapping) for the ring protons. Two
methyl resonances are observed. The 13C NMR spec-
trum is also consistent with a highly asymmetric struc-
ture with all eight ring resonances being resolved. Three
sets of resonances for the phenyl groups are observed as
well as three sets of carbonyl resonances, two of which
couple with phosphorus. A single phosphorus reso-
nance is observed at 188.5 ppm. The IR spectrum
1H and 13C NMR spectra of 8 are consistent with a
species having Cs symmetry (or averaging on the NMR
time scale). Two sets of metal carbonyl resonances are
observed with one set at 238.2 split by a phosphine
while the second set at 205.6 is not. The 31P NMR
contains three bands at 1968, 1920, and 1849 cm−1
.
The NMR spectra of 10 bear a striking resemblance to
those of Ru2(CO)(m-CO)(s-C6H5)[m-P(C6H5)2](m-h5,h5-
C5H4CH2C5H4) which is formed upon photolysis of

T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
805
Ru2(CO)4(m-h5,h5-C5H4CH2C5H4) with triphenylphos-
2.3. Solution photolyses without ligands
phine [18]. We have proposed that the ruthenium com-
pound is formed in a stepwise manner with initial
Brief photolysis of 4 in an NMR tube in deuteroben-
zene was shown by 1H NMR to form products in which
two strong metal hydride resonances were observed at
−6.35 and −10.18 ppm with an integration ratio of
approximately 2:1. The resonance at −6.35 ppm has a
pair of satellites (J=38.1 Hz) identifying it as belong-
ing to a W–H group. In addition, a number of new
resonances appeared in the ring proton region and two
sets of AB resonances appeared in the region of the
ring-bridging methylenes. Photolysis of 3 or 5 under
identical conditions produced new hydride resonances
at −4.87 and −10.22 ppm, and −4.99 and −10.15
ppm, respectively. New ring resonances were observed
in the spectra of the photoproducts, and two sets of AB
quartets for the CH2 resonances were found for 3 and
4. Two methyl resonances were observed for the photo-
product of 5. Extended photolysis of these compounds
led to the appearance of additional hydride resonances
and increasingly complex ring and bridge regions.
We have previously reported [19] that ring-coupled
bimetallic ruthenium compounds of the form, Ru2-
(CO)4(h5,h5-C5H4–L–C5H4), where L=CH2, C(CH3)2,
C2H4, or Si(CH3)2, undergo a ‘twist’ photochemical
carbonyl loss leading to formation of
a simple
triphenylphosphine derivative, followed by loss of a
second carbonyl and oxidative addition of a P–C bond
to the electron deficient metal atom. It may be impor-
tant to note that it is the ruthenium that would be
expected to lose a carbon monoxide from 8, thus the
oxidative addition steps in the diruthenium and ruthe-
nium/molybdenum cases would be identical.
Photolysis of 6 in benzene with an excess of tri-
phenylphosphine gave, after work-up, a single product,
11, as purple–red flakes. We were unable to obtain
crystallographic quality crystals from this material.
rearrangement
to
form
[Ru(CO)2][Ru(CO)2H]-
(m-h5,h5:h1-C5H4–L–C5H3). Clearly an identical reac-
tion is occurring in the case of compounds 3, 4, and 5
leading to both possible ‘twist’ isomers.
The IR spectrum of 11 contains strong bands at 1948
and 1728 cm−1 and a weak band at 1767 cm−1. The
1H NMR spectrum is slightly broadened with four sets
of ring resonances and a singlet for the bridge methyl
groups consistent with a Cs symmetry. The 13C NMR
spectrum reveals both terminal and bridging CO reso-
nances. The bridging carbonyl resonances couple with
In order to trap and isolate these twisted hydride
species, compounds 3 and 4 were photolyzed in benzene
containing 20% CHCl3. Small amounts of compounds
14 and 15 were also obtained by addition of CHCl3 to
a solution of the twist hydrides produced by photolysis
in deuterobenzene. Chromatography separated two
products in each case (12, 13 and 14, 15) and these
1
the phosphine ligand. As for the H spectrum, the ring
carbon and bridge regions require Cs symmetry.
We have recently reported [18] the synthesis of the
triphenylphosphine derivative of Fe2(CO)4(m-h5,h5-
C5H4CH2C5H4) using the same methods as used in the
present work. Two strong bands were readily assigned
1
products were characterized by IR, H and 13C NMR
spectroscopies.
as corresponding to the terminal CO (1950 cm−1
)
located along the molecular mirror plane and the asym-
metric stretching band of the bridging carbonyl groups
(1725 cm−1). A weak band at 1763 cm−1 was assigned
to the symmetric stretch of the bridging carbonyls.
These band positions correspond almost exactly to
bands observed for 11. Perhaps more diagnostic is that
the 31P NMR chemical shift of 11 is 72.33 ppm while
that of the homobimetallic iron triphenylphosphine
derivative is 71.88 ppm, suggesting that the tri-
phenylphosphine in 11 is on the iron. By way of
comparison, the 31P NMR chemical shifts for
M(CO)(PPh3)(Cl)(h5-C5H5), where M=Fe and Ru, are
64.06 and 49.29 ppm, respectively (J.E. Shade, personal
communication, 1996).
The very small quantities of samples precluded ele-
mental analysis. In both cases the isomer with the
Ru(CO)2Cl moiety was isolated in much smaller yield
than the isomer with the M(CO)3Cl group indicating
that the preference for the M(CO)3H product indicated
by NMR is preserved in the isolated chlorides. Finally,
single crystals of 13 and 14 were grown and the molec-
ular structures determined by X-ray crystallography

806
T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
Table 5
(Figs. 3 and 4). The crystallographic and refinement
data are presented in Table 1 and selected bond lengths
and angles are presented in Tables 4 and 5. The h5:h1-
C5H3 ring in these compounds is nearly perpendicular
to the h5-C5H4 rings (87.0 and 94.0°, respectively). All
bond lengths and angles are within normal ranges
,
Bond lengths (A) and angles (°) for 14
Bond lengths
Ru–Cl
2.417(3)
1.884(10)
1.876(9)
2.004(10)
1.971(9)
2.015(11)
W–C(10)
2.211(8)
Ru–C(15)
Ru–C(16)
W–C(12)
W–C(13)
W–C(14)
C(15)–O(15)
C(16)–O(16)
C(12)–O(12)
C(13)–O(13)
C(14)–O(14)
1.152(14)
1.126(12)
1.130(13)
1.171(13)
1.136(14)
Bond angles
C(15)–Ru–C(16)
Cl–Ru–C(16)
89.6(4)
94.0(3)
77.4(3)
110.5(4)
78.0(4)
176.7(8)
174.9(8)
134.5(4)
Cl–Ru–C(15)
89.3(3)
79.1(3)
137.4(4)
78.0(4)
177.0(9)
176.4(8)
177.0(9)
C(10)–W–C(12)
C(10)–W–C(14)
C(12)–W–C(14)
Ru–C(15)–O(15)
W–C(12)–O(12)
W–C(14)–O(14)
C(10)–W–C(13)
C(12)–W–C(13)
C(13)–W–C(14)
Ru–C(16)–O(16)
W–C(13)–O(13)
W–C(10)–Ru
indicating that the twisted conformation has no appar-
ent bond strain.
Evidence that will be reported elsewhere supports a
mechanism for the ‘twist’ reaction in which photolysis
results in carbonyl loss to form a coordinatively unsatu-
rated bimetallic species. Oxidative addition of a C–H
bond gives an intermediate which has M–H, M–Cp,
and M–M bonds. Reductive elimination of a M–H
and recapture of a carbon monoxide completes the
reaction sequence. In the case of the heterobimetallic
compounds described above, we have direct observa-
tion of the carbonyl loss intermediate in a Nujol matrix
[20], and have captured the carbonyl-loss intermediate
with triphenylphosphine. It is interesting that tri-
phenylphosphine appears to prefer adding to the Group
VI metal side of the molecule, while the ‘twist’ reaction
products would suggest that oxidative addition to the
ruthenium is preferred. Work on the reaction of these
heterobimetallic compounds with other ligands, partic-
ularly acetylene, is proceeding.
Fig. 3. Molecular structure of 13.
Fig. 4. Molecular structure of 14.
Table 4
,
Bond lengths (A) and angles (°) for 13
3. Experimental
Bond lengths
Ru–C(9)
Ru–C(6)
Ru–C(7)
Mo–C(13)
Mo–C(14)
Mo–C(15)
2.061(4)
1.876(4)
1.869(5)
2.005(4)
2.004(6)
1.995(6)
Mo–Cl
2.516(2)
1.141(5)
1.148(6)
1.147(6)
1.114(7)
1.135(8)
All synthesis were carried out under an atmosphere
of dinitrogen using standard Schlenk techniques. All
purification chromatography was performed using
reagent grade solvents and neutral alumina provided by
CAMAG Inc. or silica gel (Fisher Scientific). All
preparative solvents were dried and distilled under
nitrogen.
C(6)–O(6)
C(7)–O(7)
C(13)–O(13)
C(14)–O(14)
C(15)–O(15)
Bond angles
C(9)–Ru–C(6)
C(13)–Mo–C(14)
C(14)–Mo–C(15)
C(14)–Mo–Cl
Ru–C(6)–O(6)
Mo–C(13)–O(13)
Mo–C(15)–O(15)
93.5(2)
109.0(2)
75.8(2)
C(9)–Ru–C(7)
C(13)–Mo–C(15)
C(13)–Mo–Cl
C(15)–Mo–Cl
Ru–C(7)–O(7)
Mo–C(14)–O(14)
Ru–C(9)–Mo
91.4(2)
77.5(2)
77.9(1)
135.6(2)
178.1(4)
178.4(4)
128.2(2)
1H, 13C, and 13P NMR spectra were recorded on an
Bruker NR-300 spectrometer (University of Idaho) or a
QE300 NMR spectrometer (US Naval Academy).
Chemical shifts were recorded in ppm relative to te-
tramethylsilane using appropriate solvent resonances as
internal standards. IR spectra were obtained using a
78.1(1)
177.1(5)
177.2(6)
176.8(5)

T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
807
Bio-Rad Qualimatic FTIR spectrometer or a Perkin–
Elmer Spectrum 1000 FTIR. Elemental analyses were
performed by Desert Analysis of Tucson, AZ.
Compounds 1 and 2 were prepared as previously
described. Metal carbonyls were purchased from Strem
Chemicals, Inc. and used as received.
180°C decomp. IR (CH2Cl2): 2019, 1956, 1900 (sh),
1
1873 cm−1. H NMR (CDCl3): 5.40 (t, 2H, Cp), 5.24
(t, 2H, Cp), 5.10 (t, 2H, Cp), 5.08 (t, 2H, Cp), 1.49
(CMe2). 13C NMR (CDCl3): 219.4 (M–CO averaged
signal), 117.4 (ipso Cp), 111.5 (ipso Cp), 86.7 (Cp),
86.4 (Cp), 85.0 (Cp), 84.5 (Cp), 35.5 (CMe2), 30.8
(CH3).
3.1. Synthesis of RuMo(CO)5(v-p5,p5-C5H4CH2C5H4)
(3)
3.4. Synthesis of RuFe(CO)4[v-p5,p5-C5H4C-
(CH3)2C5H4] (6)
Compound 1 (159 mg, 0.67 mmol) and Mo(CO)6
(165 mg, 0.67 mmol) were taken up in butyl ether (16
ml) in a 25 ml Schlenk flask. The contents of the flask
were freeze–pump–thawed three times and then sealed
under vacuum and heated at 120°C overnight. After
removal of the solvent the remaining red residue was
washed with petroleum ether. The resulting residue was
shown by HPLC and subsequent analysis to be pure 3
as a red–orange solid, 110 mg, 34%. M.p. 180°C de-
Compound 2 (150 mg, 0.46 mmol) and Fe(CO)5 (450
mg, 2.3 mmol) were charged into a 100 ml Schlenk
flask. After addition of xylene (50 ml) the reaction
mixture was refluxed overnight under nitrogen. Re-
moval of the xylene under vacuum yielded a dark
brown residue which was taken up in a minimum
quantity of petroleum ether:dichloromethane (1:1) and
chromatographed on alumina using the same solvent as
the eluant. A single band was eluted. Removal of
solvent yielded 6 as an orange–red solid, 164 mg, 87%.
comp. IR (CH2Cl2): 2020, 1957, 1900 (sh), 1873 cm−1
.
1H NMR (C6D6): 4.67 (m, 4H, Cp), 4.30 (m, 4H, Cp),
2.71 (s, 2H, CH2). 13C NMR (C6D6): 220.0 (M–CO
averaged signal), 105.3 (ipso Cp), 101.2 (ipso Cp), 89.3
(Cp), 87.5 (Cp), 86.8 (Cp), 84.5 (Cp), 26.3 (CH2).
M.p. 193–194°C. IR (CH2Cl2): 1997, 1955, 1777 cm−1
.
1H NMR (CDCl3): 5.51 (b protons, ring 1), 5.46 (a
protons, ring 1), 5.09 (b protons, ring 2) 4.09 (a pro-
tons, ring 2), 1.47 (s, CH3). 13C NMR (CDCl3): 229.2,
109.8 (ipso Cp), 108.8 (ipso Cp), 91.3 (a carbon, ring 1),
89.1 (a carbon, ring 2), 85.2 (b carbon, ring 1), 81.2 (b
carbon, ring 2), 32.5 (CMe2), 29.4 (CH3). MS (FAB):
439 (M+), 411 (M+–CO), 383 (M+–2CO), 355 (M+–
3CO), 327 (M+–4CO or –Fe(CO)2).
3.2. Synthesis of RuW(CO)5[p5,p5-C5H4CH2C5H4] (4)
Compound 1 (200 mg, 0.67 mmol) and W(CO)3-
(CH3CN)3 (318 mg, 0.67 mmol) were charged into a
100 ml Schlenk flask. The flask was evacuated and
backfilled with nitrogen, then xylene (50 ml) was added.
The flask was fitted with a condenser and the reaction
mixture refluxed overnight under nitrogen. After re-
moval of the xylene under vacuum, the red crystalline
residue was taken up in dichloromethane and chro-
matographed on alumina using dichloromethane as the
eluant. A single band was eluted. Removal of solvent
yielded 4 as an orange–red solid, 200 mg, 53%. M.p.
211–213°C. IR (CH2Cl2): 2019, 1973 (sh), 1955, 1889
3.5. Synthesis of RuNi(CO)3[v-p5,p5-C5H4C-
(CH3)2C5H4] (7)
Compound 2 (50 mg, 0.15 mmol) and xylene (10 ml)
were added to a 25 ml Schlenk flask and freeze–pump–
thawed three times. An excess of Ni(CO)4 was con-
densed into the flask and the flask sealed under
vacuum. The reaction mixture was heated overnight at
87°C. Removal of solvent and unreacted Ni(CO)4 under
vacuum gave a brown residue that was taken up in
petroleum ether:dichloromethane (10:1) and chro-
matographed on alumina with the same solvent as
eluant. A single red–brown band was eluted which
gave a red–brown solid upon removal of solvent. IR
showed traces of 2 in this material and subsequent
studies demonstrated that 7 decomposes over time at
r.t. to give 2 and an unidentified nickel product. IR
1
(sh), 1867 cm−1. H NMR (CDCl3): 5.44 (t, 2H, Cp),
5.27 (t, 2H, Cp), 5.15 (t, 2H, Cp), 4.96 (t, 2H, Cp), 3.77
(s, CH2). All Cp resonances were clean AA%BB% triplets.
13C NMR (CDCl3, 298°C): 104.5 (ipso Cp), 102.2 (ipso
Cp), 88.6 (Cp), 87.9 (Cp), 85.9 (Cp), 85.2 (Cp), 27.1
(CH2). M–CO found at 212.3 ppm at 325°C.
3.3. Synthesis of RuMo(CO)5[v-p5,p5-C5H4C-
(CH3)2C5H4] (5)
Compound 2 (494 mg, 1.51 mmol) and Mo(CO)6
(397 mg, 1.51 mmol) were taken up in xylene as de-
scribed for 4 and refluxed overnight. After removal of
solvent, the residue was chromatographed on alumina
with petroleum ether:dichloromethane (3:1) as an elu-
ant. A single red–orange band was eluted which yielded
5 as a red–orange crystalline solid, 605 mg, 79%. M.p.
.
(CH2Cl2): 2017, 1959, 1943 (sh) cm−1 1H NMR
(C6D6): 5.54 (t, 2H, Cp), 4.93 (t, 2H, Cp), 4,65 (t, 2H,
Cp), 4.40 (t, 2H, Cp), 1.06 (CMe2). 13C NMR (C6D6):
201.3 (M–CO averaged signal), 97.5 (ipso Cp), 93.7
(Cp), 87.4 (Cp), 84.8 (Cp), 80.0 (Cp), 34.8 (CMe2), 29.6
(CH3).

808
T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
3.6. Synthesis of [Ru(CO)2][Mo(CO)2P(C6H5)3]-
[v-p5,p5-C5H4C(CH3)2C5H4][Ru–Mo] (8),
[RuP(C6H5)3][Mo(CO)2](v-CO)2[v-p5,p5-C5H4C-
(CH3)2C5H4][Ru–Mo] (9), and [Ru(|-C6H5)(CO)]-
[Mo(CO)][v-P(C6H5)2](v-CO)[v-p5,p5-C5H4C(CH3)2-
C5H4][Ru–Mo] (10)
J
P–C=9.5 Hz, o-Ph a), 132.3 (d, JP–C=11.0 Hz, o-Ph
b), 129.2 (s, p-Ph a), 128.3 (s, p-Ph b), 127.9 (d,
J
J
Cp), 102.0 (ipso Cp), 96.0 (Cp), 92.4 (Cp), 88.7 (Cp),
88.1 (Cp), 88.0 (Cp), 85.2 (Cp), 82.5 (Cp), 79.6 (Cp),
35.5 (CMe2), 35.0 (CH3), 29.6 (CH3). 31P NMR
(CDCl3): 188.5 ppm.
P–C=9.1 Hz, m-Ph a), 126.8 (s, m s-Ph), 126.7 (d,
P–C=9.6 Hz, m-Ph b), 121.7 (s, p s-Ph), 115.8 (ipso
Compound 5 (100 mg, 0.21 mmol) and triphenyl-
phosphine (55 mg, 0.21 mmol) were taken up in ben-
zene and photolyzed for 30 min in a water-jacketed
Pyrex cell. During photolysis the solution turned from
orange to red. After removal of solvent the residue was
taken up in petroleum ether:dichloromethane (5:2)
and chromatographed on alumina. Four bands were
eluted from the column. In order, the bands were found
to be: 5 (orange), 8 (red–orange), 10 (purple), and 9
(orange).
3.7. Synthesis of RuFe(CO)3[P(C6H5)3][v-p5,p5-
C5H4C(CH3)2C5H4] (11)
Compound
6
(100 mg, 0.227 mmol) and
triphenylphosphine (60 mg, 0.229 mmol) were taken up
in benzene (15 ml) and photolyzed in a Pyrex water-
jacketed cell for 30 min. During photolysis the solution
turned from brown to red. After removal of solvent the
residue was taken up in petroleum ether:dichloro-
methane (10:1) and chromatographed on an alumina
column. A single rose band was eluted. Removal of
solvent gave 11 as a purple–red solid, 42 mg, 44%. IR
Compound 8 was isolated as a red–orange solid.
M.p. 219–221°C. IR (CH2Cl2): 1992 (s), 1933 (s), 1876
1
(m), 1814 (s) cm−1. H NMR (CDCl3): 7.35 (m, 15H,
Ph), 5.39 (m, 2H, Cp), 5.03 (m, 2H, Cp), 4.82 (m, 2H,
Cp), 4.47 (m, 2H, Cp), 1.44 (s, CH3). 13C NMR
(CDCl3): 238.1 (d, JP–C=22.7 Hz, Mo–CO), 205.6
(Ru–CO), 137 (broad, ipso Ph), 133.3 (d, JP–C=10.2
Hz, o-Ph), 129.6 (s, p-Ph), 128.0 (d, JP–C=9.7 Hz,
m-Ph), 115.7 (ipso Cp), 115.1 (ipso Cp), 88.6 (Cp), 85.8
(CH2Cl2): 1950 (s), 1763 (w), 1725 (s) cm−1. H NMR
1
(CDCl3): 7.53 (3H, PPh3), 7.31 (12H, PPh3), 5.48 (2H,
Cp), 5.32 (2H, Cp), 4.88 (2H, Cp), 3.94 (2H, Cp), 1.49
(s, 6H, CH3). Note: all resonances in the proton spec-
trum were broadened obscuring fine structure. 13C
NMR (CDCl3): 270.8 (d, JP–C=15 Hz, m-CO), 202.2
(terminal CO), 134.8 (d, J=42.8 Hz, ipso Ph), 133.8 (d,
(Cp), 84.4 (Cp), 84.0 (Cp), 35.8 (CMe2), 31.0 (CH3). 31
NMR (CDCl3): 77.2 ppm.
P
Compound 9 was isolated as an orange solid. M.p.
JP–C=9.2 Hz, o-Ph), 129.6 (s, p-Ph), 127.9 (d, JP–C=
213–217°C. IR (CH2Cl2): 1949 (s), 1909 (s), 1852 (m),
9.4 Hz, m-Ph), 110.6 (ipso Cp), 104.8 (ipso Cp), 91.4
(Cp), 88.0 (Cp), 84.0 (Cp), 83.7 (Cp), 31.9 (CMe2), 30.0
(CH3). 31P NMR (CDCl3): 72.33 ppm.
1
1730 (m) cm−1. H NMR: (CDCl3): 7.33 (m, 15H, Ph),
5.39 (AA%BB%, 2H, ring 1a), 5.15 (m, 2H, ring 2a), 5.04
(AA%BB%, 2H, ring 1b), 4.58 (m, 2H, ring 2b), 1.53
(CH3). 13C NMR (CDCl3): 236.7 (d, JP–C=31.5 Hz,
terminal M–CO), 134.6 (d, JP–C=43.3 Hz, ipso Ph),
133.5 (d, JP–C=11.1 Hz, o-Ph), 129.9 (d, JP–C=2 Hz,
p-Ph), 128.0 (d, JP–C=10.1 Hz, m-Ph), 108.4 (ipso Cp),
108.2 (ipso Cp), 90.4 (ring 2a), 87.7 (ring 1a), 87.4 (ring
2b), 85.8 (ring 1b), 34.1 (CMe2), 31.1 (CH3). 31P NMR
(CDCl3): 48.2 ppm.
3.8. Photolysis of 3 and 4 in benzene:CHCl3 (3:1)
Compound 3 (100 mg, 0.21 mmol) was taken up in
benzene:CHCl3 (3:1), 10 ml, in an Ace quartz minipho-
tochemical reactor equipped with a cold finger and
photolyzed for 15 min with a 350 W high pressure
mercury lamp. Column chromatography on alumina
using petroleum ether:dichloromethane (3:1) as an elu-
ant yielded two bands. The first orange band was
stripped of solvent to give 13 as an orange crystalline
solid. IR (CH2Cl2): 2048, 2029, 1981, 1959, 1943 sh
Compound 10 was recovered as a purple solid both
from the photolysis of 5 in the presence of triphenyl-
phosphine and photolysis of 8 in the absence of addi-
1
tional ligands. IR (CH2Cl2): 1968, 1920, 1844 cm−1. H
1
NMR (CDCl3): 7.80 (m, 2H, ortho protons s phenyl),
7.43 (m, 3H, meta, para protons s phenyl), 7.20 (m,
2H, para protons PPh2), 6.90 (m, 4H, ortho protons
PPh2), 6.58 (m, 4H, meta protons PPh2), 5.60 (m, 1H,
H-2), 5.27 (1H, H-10), 5.21 (m, 1H, H-9), 5.12 (m, 2H,
H-3 and H-11), 4.91 (m, 1H, H-4), 4.51 (m, 1H, H-8),
4.02 (m, 1H, H-5), 1.62 (s, 3H, CH3-12), 1.33 (s, 3H,
CH3-13). 13C NMR (CDCl3): 240.8 (d, JP–C=25.4 Hz,
Mo–CO), 239.4 (s, Mo–CO), 205.4 (d, JP–C=8.8 Hz,
Ru–CO), 144.6 (s, ortho s-Ph), 142.5 (d, JP–C=30.75
cm−1. H NMR: (CDCl3) 5.79 (1H, m, ring 1), 5.63
(1H, m, ring 1), 5.55 (1H, m, ring 1), 5.43 (1H, m, ring
2), 5.28 (1H, m, ring 1), 5.01 (1H, m, ring 2), 4.63 (1H,
m, ring 2), 3.33 and 3.10 (AB quartet, J=16.8 Hz). 13C
NMR (CDCl3): 243.1 (axial Mo–CO), 227.9 (equatorial
Mo–CO), 224.2 (equatorial Mo–CO), 199.3 (Ru–CO),
198.5 (Ru–CO), 157.3 (ipso Cp), 130.2 (ipso Cp), 114.0
(ipso Cp), 92.3 (Cp), 91.1 (Cp), 90.8 (Cp), 87.0 (Cp),
86.9 (Cp), 85.3 (Cp), 83.9 (Cp), 82.3 (Cp), 81.9 (Cp),
27.3 (CH2). The second yellow band was collected and
removal of solvent gave 12 as a yellow powder. IR
Hz, ipso Ph), 140.0 (d,
JP–C=16.3 Hz, ipso
s-Ph), 140.6 (d, JP–C=42.8 Hz, ipso Ph), 133.4 (d,
(CH2Cl2): 2050, 2031, 2000, 1966, 1943 cm−1
.

T.E. Bitterwolf et al. / Inorganica Chimica Acta 300–302 (2000) 800–809
809
contained in the SHELXTL PLUS (4.2) program library
(G. Sheldrick, Siemens XRD, Madison, WI).
Compound 4 was photolyzed in a manner identical
to 3. Chromatography yielded two bands. The first
yellow band yielded 14 as yellow crystals. IR (CH2Cl2):
1
2047, 2028, 1999, 1953, 1931 cm−1. H NMR (CDCl3):
References
6.65 (1H, m), 6.05 (1H, m), 5.30 (1H, m), 5.04 (1H, m),
5.00 (1H, m), 4.82 (1H, m), 4.70 (1H, m), 3.29 and 3.02
(AB quartet, J=27.3 Hz). 13C NMR (CDCl3): 225.0
(Mo–CO), 214.5 (Mo–CO), 198.0 (Ru–CO), 197.7
(Ru–CO), (ipso not located), 92.8 (Cp), 92.6 (Cp), 92.1
(Cp), 83.8 (Cp), 82.2 (Cp), 81.8 (Cp), 77.2 (Cp), 25.7
(CH2). The second orange band yielded 15 as orange
crystals. M.p. 165–167°C. IR (CH2Cl2): 1944, 1927,
1980, 1944 cm−1. 1H NMR (CDCl3): 5.73 (1H, m), 5.63
(1H, m), 5.56 (1H, m), 5.53 (1H, m), 5.27 (1H, m), 5.19
(1H, m), 4.67 (1H, m), 2.29 and 3.5 (AB quartet,
J=16.7 Hz). 13C NMR (CDCl3): 232.0 (axial W–CO),
219.3 (equatorial W–CO), 218.0 (equatorial W–CO),
199.3 (Ru–CO), 198.6 (Ru–CO), 154.7 (ipso), 129.9
(ipso), 111.7 (ipso), 91.3 (Cp), 90.2 (Cp), 88.9 (Cp), 85.4
(Cp), 85.1 (Cp), 84.1 (Cp), 81.7 (Cp), 27.2 (CH2).
[1] (a) K.P.C. Vollhardt, T.W. Weidman, J. Am. Chem. Soc. 105
(1983) 1676. (b) P.K.C. Vollhardt, T.W. Weidman,
Organometallics 3 (1984) 82.
[2] M.A. Huffman, PhD Thesis, University of California, Berkeley,
1984.
[3] A.P. Kahn, D.A. Newman, K.P.C. Vollhardt, Synlett (1991) 141.
[4] (a) J.S. Drange, M. Tilset, K.P.C. Vollhardt, T.W. Weidman,
Organometallics 3 (1984) 812. (b) R. Boese, M.A. Huffman,
K.P.C. Vollhardt, Angew. Chem., Int. Ed. Engl. 30 (1991) 812.
[5] M.-H. Deville-Desbois, D.S. Brown, P.K.C. Vollhardt, D. As-
truc, J. Chem. Soc., Chem. Commun. (1991) 1355.
[6] (a) H. Werner, D. Schneider, M. Schulz, Chem. Ber. 125 (1992)
1017. (b) H. Werner, Inorg. Chim. Acta 198–200 (1992) 715.
[7] P. Ha¨rter, G. Boguth, E. Herdtweck, J. Riede, Angew. Chem.,
Int. Ed. Engl. 28 (1989) 1008.
[8] A. Cassens, P. Eilbracht, A. Nazzal, W. Pro¨ssdorf, U.T.
Mueller-Westerhoff, J. Am. Chem. Soc. 103 (1981) 6367.
[9] J. Heck, J. Ko¨rnich, J. Organomet. Chem. 543 (1997) 153.
[10] (a) G.M. Diamond, M.L.H. Green, N.A. Popham, A.N.
Chernega, J. Chem. Soc., Chem. Commun. (1994) 727. (b) G.M.
Diamond, M.L.H. Green, P. Mountford, N.A. Popham, A.N.
Chernega, J. Chem. Soc., Chem. Commun. (1994) 103.
[11] S.F. Amevor, H.-U. Hund, A. Salzer, J. Organomet. Chem. 520
(1996) 79.
3.9. Crystallographic studies
Crystal, data collection, and refinement parameters
are given in Table 1. Suitable crystals were selected and
mounted on glass fibers with epoxy cement. The unit-
cell parameters were obtained by the least-squares refin-
ement of the angular settings of 24 reflections
(20°5q524°).
[12] T.E. Bitterwolf, M.B. Leonard, P.A. Horine, J.E. Shade, A.L.
Rheingold, D.J. Staley, G.P.A. Yap, J. Organomet. Chem. 512
(1996) 11.
[13] S.A.R. Knox, K.A. Macpherson, A.G. Orpen, M.C. Rendle, J.
Chem. Soc., Dalton Trans. (1989) 1807.
The systematic absences in the diffraction data are
uniquely consistent for space groups P21/c for 3, 13,
and 14; and for P21/n for 4. The structures were solved
using direct methods, completed by subsequent differ-
ence Fourier synthesis and refined by full-matrix least-
squares procedures. Semi-empirical ellipsoid absorption
corrections were applied. All non-hydrogen atoms were
refined with anisotropic displacement coefficients. Hy-
drogen atoms were treated as idealized contributions.
The largest remaining peaks in the difference map for 3,
[14] T.E. Bitterwolf, A.L. Rheingold, Organometallics 10 (1991)
3856.
[15] (a) B.P. Gracey, S.A.R. Knox, K.A. Macpherson, A.G. Orpen,
S.R. Stobart, J. Chem. Soc., Dalton Trans. (1985) 1935. (b) S.N.
Cesaro, S. Dobos, Vibrational Spectroscopy, vol. 6, 1993, p. 119.
[16] T. Blackmore, J.D. Cotton, M.I. Bruce, F.G.A. Stone, J. Chem.
Soc. (A) (1968) 2931.
[17] T.E. Bitterwolf, A. Saygh, J.E. Shade, A.L. Rheingold, G.P.A.
Yap, L. Liable-Sands, J. Organomet. Chem. 562 (1998) 89.
[18] T.E. Bitterwolf, J.L. Haener, J.E. Shade, A.L. Rheingold,
G.P.A. Yap, J. Organomet. Chem. 577 (1997) 23.
[19] T.E. Bitterwolf, J.E. Shade, J.A. Hansen, A.L. Rheingold, J.
Organomet. Chem. 514 (1996) 13.
4, and 14 (1.0–1.2 e A−3) occur at chemically unrea-
,
sonable positions and were treated as noise.
[20] T.E. Bitterwolf, J.T. Bays, C.A. Weiss, W.B. Scallorn, A.J. Rest,
unpublished data.
All software and sources of the scattering factors are
.
.