Syntheses and structures of homo- and heterobimetallic complexes containing a (cyclopentadienone)rhodium(I) fragment

Article abstract of DOI:10.1002/hlca.200590028

The reaction of [RhCl(n⁴-Ph₂R₂C ₄CO)]₂ (R = Ph, 2-naphthyl) with the dimeric complexes [RuCl₂(p-cymene)]₂ p-cymene = 1-methyl-4-(1-methylethyl) benzene, [RuCl₂(1,3,5-Et₃C₆H₃)] ₂, [MCl₂(Cp*)]₂ (M = Rh, Ir; Cp* = 1,2,3,4,5-pentamethylcyclopenta-2,4-dien-1-yl), [RuCl₂(CO) ₃]₂, [RuCl₂(dcypb)(CO)]₂ (dcypb = butane-l,4-diylbis[dicyclohexylphosphine]), [(dppb)ClRu(μ-Cl) ₂(μ-OH₂)RuCl(dppb)] (dppb = butane-1,4- diylbis[diphenylphosphine]), and [(dcypb)(N₂)Ru(μ-Cl) ₃RuCl(dcypb)] was investigated. In all cases, mixed, chloro-bridged complexes were formed in quantitative yield (see 5-8, 9-16, 18, 19, 21, and 22). The six new complexes 5, 8, 9,13, 15, and 22 were characterized by single-crystal X-ray analysis (Figs. 1-3).

Full text of DOI:10.1002/hlca.200590028

Helvetica Chimica Acta ± Vol. 88 (2005)
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Syntheses and Structures of Homo- and Heterobimetallic Complexes
Containing a (Cyclopentadienone)rhodium(I) Fragment
by SeÂbastien Gauthier, Rosario Scopelliti, and Kay Severin*
Â
Â
 Â
Institute des Sciences et Ingenierie Chimiques, Ecole Polytechnique Federale de Lausanne (EPFL),
CH-1015 Lausanne
(phone: ‡ 41(0)216939302; e-mail: kay.severin@epfl.ch)
Â
Dedicated to Professor Andre E. Merbach on the occasion of his 65th birthday
The reaction of [RhCl(h4-Ph2R2C4CO)]2 (R ˆ Ph, 2-naphthyl) with the dimeric complexes [RuCl2(p-
cymene)]2 p-cymene ˆ 1-methyl-4-(1-methylethyl)benzene, [RuCl2(1,3,5-Et3C6H3)]2, [MCl2(Cp*)]2 (M ˆ Rh,
Ir; Cp* ˆ 1,2,3,4,5-pentamethylcyclopenta-2,4-dien-1-yl), [RuCl2(CO)3]2, [RuCl2(dcypb)(CO)]2 (dcypb ˆ bu-
tane-1,4-diylbis[dicyclohexylphosphine]), [(dppb)ClRu(m-Cl)2(m-OH2)RuCl(dppb)] (dppb ˆ butane-1,4-diyl-
bis[diphenylphosphine]), and [(dcypb)(N2)Ru(m-Cl)3RuCl(dcypb)] was investigated. In all cases, mixed,
chloro-bridged complexes were formed in quantitative yield (see 5 ± 8, 9 ± 16, 18, 19, 21, and 22). The six new
complexes 5, 8, 9, 13, 15, and 22 were characterized by single-crystal X-ray analysis (Figs. 1 ± 3).
1. Introduction. ± Complexes in which a metal fragment A is connected by two or
three halogeno bridges to a different metal fragment B [1] have emerged as a promising
new class of catalysts. They have been used for olefin metathesis reactions [2], for
Oppenauer-type oxidations [3], for atom-transfer radical additions [4], and for atom-
transfer radical polymerizations [5]. Two of the recently described catalysts are 1 and 2.
Complex 1 was identified as a potent and robust catalyst for the addition of CCl4 to
olefins [4b], and complex 2 can be used to oxidize primary and secondary alcohols by
using acetone as the solvent and oxidation agent [3a]. Since both complexes contain a
RhI(h4-Ph4C4CO) fragment, we were interested to develop a general synthetic route
which provides access to homo- and heterobimetallic complexes containing this
fragment. In the following, the results of these studies are reported.
2. Results and Discussion. ± For the synthesis of mixed complexes with two
halogeno bridges, metathesis reactions with the corresponding homobimetallic
complexes were found to be very useful (Scheme 1). Reactions of this kind were first
ꢀ 2005 Verlag Helvetica Chimica Acta AG, Zürich

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described by Stone and co-workers [6] and Masters and co-workers [7], but more-
detailed investigations which demonstrate the potential of this method have been
published only recently [8][9].
Scheme 1. Metathesis Reaction for the Synthesis of Mixed Chloro-Bridged Complexes
To investigate whether a metathesis reaction of this kind is suited to synthesize
mixed complexes containing a RhI(h4-Ph2R2C4CO) fragment and a RuII(arene)
fragment, we first carried out reactions between the dimeric complexes 3 and 4 and
the complexes [RuCl2(p-cymene)]2 (p-cymene ˆ 1-methyl-4-(1-methylethyl)benzene)
and [RuCl2(1,3,5-Et3C6H3)]2 (Scheme 2). In situ 1H-NMR experiments (CDCl3)
showed in all cases the fast and quantitative formation of a new complex, i.e., of 5 ± 8.
Scheme 2. Synthesis ofthe Heterobimetallic Rh/Ru Complexes 5 ± 8. Nph ˆ 2-naphthyl.
The formation of heterobimetallic RhI/RuII complexes was confirmed by the results
of single-crystal X-ray analyses of 5 and 8 (Fig. 1). Contrary to what is found for the
two starting materials, the products display three and not two chloro bridges, resulting
in a five-coordinated, electronically saturated configuration at the Rh-center. It should
be noted that (cyclopentadienone)rhodium complexes have a tendency to form piano-
stool-type complexes [10], a fact that is also evident from the molecular structures of 1
and 2. The formation of this additional chloro bridge probably contributes to the
driving force for the reaction. The MÀCl and the MÀC bond distances are very similar
for 5 and 8 (Table 1). With 2.412(3) Š (5) and 2.434(5) Š (8), the C-atoms of the
carbonyl group are further apart from the Rh-atom than the olefinic C-atoms,
indicating a h4-coordination of the cyclopentadienone ligands. The phenyl and the 2-
naphthyl groups adopt a ꢁpropellerꢂ conformation with angles between 27.38 and 54.38
between their normals and the normal to the mean plane through atoms C(2), C(3),
C(4), and C(5).

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Fig. 1. ORTEP [11] Representation ofthe molecular structure of 5 and 8 in the crystal. The H-atoms are not
shown for clarity.
The homodimeric complexes [MCl2(Cp*)]2 (M ˆ Rh, Ir; Cp* ˆ 1,2,3,4,5-penta-
methylcyclopenta-2,4-dien-1-yl), [RuCl2(CO)3]2, and [RuCl2(dcypb)(CO)]2 (dcypb ˆ
butane-1,4-diylbis[dicyclohexylphosphine] react with the rhodium compounds 3 and 4
in a similar fashion as it was found for the [RuCl2(arene)]2 complexes. This was
evidenced by the synthesis of the mixed complexes 9 ± 16, which were obtained in
excellent yields in chloro bridge metatheses reactions.
A single-crystal X-ray analysis was carried out for one complex of each class. The
geometries that were determined resemble those of 5 and 8: a h4-bound (cyclo-
pentadienone)rhodium fragment is connected via three chloro bridges to a RhIII(Cp*)
fragment (see 9), a RuII(CO)3 fragment (see 13), or a RuII(dcypb)(CO) fragment (see
15) (Fig. 2). A summary of selected bond lengths is given in Table 1.
The bis(phosphine)ruthenium catalysts 1 and 2 were obtained by reaction of 3 with
the dinitrogen complex 17 [4b] or the acetone complex [(PPh3)2ClRu(m-Cl)3Ru(ace-
tone)(PPh3)2] [3a]. In both complexes, a RuCl2(phosphine)2 fragment is stabilized by
coordination to a RhCl(h4-Ph4C4CO) fragment, but for complex 2, the electronic

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Table 1. Selected Bond Lengths [Š] for the Complexes 5, 8, 9, 13, 15, and 22
RhÀCla)
MÀCla)
RhÀC(1)
RhÀC(2)
RhÀC(3)
RhÀC(4)
RhÀC(5)
5
8
9
13
15
22
2.500
2.483
2.486
2.523
2.474
2.488
2.438
2.433
2.446
2.417
2.496
2.470
2.412(3)
2.434(5)
2.401(3)
2.424(5)
2.371(8)
2.420(5)
2.156(4)
2.123(5)
2.147(3)
2.145(5)
2.143(7)
2.159(5)
2.110(4)
2.114(5)
2.099(3)
2.116(4)
2.113(7)
2.101(5)
2.109(4)
2.097(5)
2.106(3)
2.108(4)
2.099(7)
2.126(5)
2.143(4)
2.138(5)
2.160(3)
2.137(5)
2.120(6)
2.127(4)
a) Averaged values are given.
saturation of the Ru-center is achieved by coordination to a weakly bound acetone
ligand and not by dimerization via a dinitrogen bridge. The dinitrogen bridge, however,
can be replaced by an acetone ligand. This was confirmed by the synthesis of the
heterobimetallic complexes 18 and 19 in CH2Cl2/acetone 9 :1as the solvent ( Scheme 3).
Furthermore, it is possible to make the analogous dppb complexes 21 and 22 by using
the aqua complex 20 instead of the dinitrogen complex 17 (dppb ˆ butane-1,4-
diylbis[diphenylphosphine].
Scheme 3. Synthesis ofthe Heterobimetallic Rh/Ru Complexes 18, 19, 21, and 22
In solution, the presence of excess acetone is crucial for the stability of the dppb
complexes 21 and 22. When they were dissolved in plain CDCl3 or C6D6, several new
peaks were immediately observed by 31P-NMR. In the presence of 10% (D6)acetone,
however, the complexes were stable, as evidenced by a single peak in the 31P-NMR
spectrum at d ca. 47. This behavior is in contrast to what was found for the dcypb
complexes 18 and 19, for which no immediate decomposition in C6D6 was observed.

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Fig. 2. ORTEP [11] Representation ofthe molecular structure of 9, 13, and 15 in the crystal. The H-atoms are not
shown for clarity.
This difference could be explained by the reduced steric demand of the dppb ligand as
compared to the dcypb ligand, which makes the labile acetone ligand more accessible.
For complex 22, we were able to obtain single crystals, which were suited for
crystallographic analysis. As expected, its structure is similar to that of complex 2: a
RuCl2(dppb) fragment is connected via three chloro bridges to a RhCl[h4-
Ph2(Nph)2C4CO] fragment with the remaining coordination site at the Ru-atom being
occupied by an acetone ligand (Fig. 3, Table 1). The resulting octahedral Ru-center is

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Fig. 3. ORTEP [11] Representation ofthe molecular structure of 22 in the crystal. The H-atoms are not shown
for clarity.
slightly distorted as a result of the two sterically demanding phosphine ligands
(P(1)ÀRu(1)ÀP(2) ˆ 93.508).
3. Conclusions.
± Mixed, chloro-bridged complexes containing a
RhI(h4-
Ph2R2C4CO) fragment were obtained in metathesis reactions of the homodimeric
complexes 3 or 4 with complexes of the general formula [LnClM(m-Cl)2MClLn]
(Scheme 4) or with the bis[phosphine]ruthenium complexes 17 and 20. These reactions
give access to complexes containing various organometallic fragments such as
RuCl2(arene), RuCl2(CO)3, RuCl2(dcypb)(CO), RuCl2(dcypb)(acetone), RuCl2(dppb)-
(acetone), RhCl2(Cp*), and IrCl2(Cp*). Crystallographic data revealed that the mixed
complexes all contain a triple chloro bridge. The additional MÀCl interactions found
for the products are likely to be responsible for the fact that the metathesis reaction is
shifted completely towards the mixed complexes (for less-biased chloro bridge
metathesis reactions, see [7][9a]). All reactions described above were completed
within minutes and proceeded with excellent yields. The latter point is of interest for
applications in homogeneous catalysis because the mixed complexes can be prepared in
situ prior to the reaction.
Scheme 4. General Synthesis ofMixed, Chloro-Bridged Complexes Containing a Rh 1(h4-Ph2R2C4CO) Fragment

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Financial support from the Swiss National Science Foundation is gratefully acknowledged.
Experimental Part
General. The synthesis of all complexes was performed under dry N2 or Ar by using standard Schlenk
techniques. The complexes [RhCl(h4-Ph4C4CO)]2 (3) [12], [RuCl2(p-cymene)]2 [13], [RuCl2(1,3,5-Et3C6H3)]2
[14], [RhCl2(Cp*)]2 [15], [IrCl2(Cp*)]2 [15], [RuCl2(dcypb)(CO)]2 [16], [(dcypb)(N2)Ru(m-Cl)3RuCl(dcypb)]
(17) [17], and [(dppb)ClRu(m-Cl)2(m-OH2)RuCl(dppb)] (20) [18] were prepared according to literature
procedures. [RuCl2(CO)3]2 and 1,4-bis(diphenylphosphino)butane (ˆ butane-1,4-diylbis[diphenylphosphine];
dppb) were purchased from Acros, and 1,4-bis(dicyclohexylphosphino)butane (ˆ butane-1,4-diylbis[dicyclo-
hexylphosphine]; dcypb) was purchased from Aldrich. CC ˆ Column chromatography. IR spectra: n in cmÀ1. 1H-
and 13C-NMR Spectra: Bruker Avance-DPX-400 or Bruker Advance-200 spectrometer; residual protonated
solvents as internal standards; d in ppm, J in Hz. All spectra were recorded at r.t.
Di-m-chlorobis[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one]dirhodium
([RhCl{h4-Ph2(Nph)2C4CO}]2; 4). A soln. of 3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one
(1.45 g, 3 mmol) and [RhCl(C2H4)]2 (0.50 g, 1.25 mmol) in THF (50 ml) was heated under reflux for 24 h.
The soln. was concentrated to 5 ml and then subjected to CC (silica gel, CHCl3/MeOH 98 :2): 4 (0.85 g, 55%).
Dark red powder. IR: 1648 (CO). 1H-NMR (400 MHz, CDCl3): 7.03 ± 7.65 (m, 48 H, Ph, Nph). 13C-NMR
(101 MHz, CDCl3): 68.36 (d, 1J(Rh,C) ˆ 12, CÀPh); 94.31( d, 1J(Rh,C) ˆ 12, CÀNph); 125.83 ± 132.77 (m, Ph,
Nph); 165.31 (CO). Anal. calc. for C74H48Cl2O2Rh2 ´ 1/5 CHCl3: C 70.19, H 3.83; found: C 70.09, H 4.18.
Tri-m-chloro[h6-1-methyl-4-(1-methylethyl)benzene]{[(2,3,4,5-h)-2,3,4,5-tetraphenylcyclopenta-2,4-dien-1-
one]rhodium}ruthenium [(p-cymene)Ru(m-Cl)3Rh(h4-Ph4C4CO)]; 5). [RuCl2(p-cymene)]2 (65 mg, 106 mmol)
and [RhCl2(h4-Ph4C4CO)]2 (111 mg, 106 mmol) in degassed CH2Cl2 (8 ml) were stirred for 30 min. After
evaporation, the product was washed with pentane and dried under vacuum: 5 (92%). Red crystals were
obtained by slow diffusion of pentane into a soln. of 5 in CH2Cl2. IR: 1647 (CO). 1H-NMR (400 MHz, CDCl3):
1.31 (d, 3J ˆ 7, Me2CH); 2.19 (s, Me); 2.86 (sept., 3J ˆ 7, Me2CH); 5.27 (d, 3J ˆ 6, 2 arom. H (cym.)); 5.53 (d, 3J ˆ
6, 2 arom. H (cym.)); 7.06 ± 7.67 (m, 20 H, Ph). 13C-NMR (101 MHz, CDCl3): 18.93, 22.22 (Me); 31.33 (Me2CH);
68.07 (d, 1J(Rh,C) ˆ 12, CÀPh); 77.75, 80.29 (CH (cym.)); 93.89 (d, 1J(Rh,C) ˆ 12, CÀPh); 96.88, 100.24 (C
(cym.)); 127.21 ± 131.67 (Ph); 165.50 (CO). Anal. calc. for C39H34Cl3ORhRu: C 56.50, H 4.13; found C 56.82, H
4.11.
Tri-m-chloro{[(2,3,4,5-h)-2,3,4,5-tetraphenylcyclopenta-2,4-dien-1-one]rhodium}(h6-1,3,5-triethylbenzene)-
ruthenium ([(1,3,5-Et3C6H3)Ru(m-Cl)3Rh(h4-Ph4C4CO)]; 6). As described for 5, with [RuCl2(1,3,5-Et3C6H3)]2
and [RhCl(h4-Ph4C4CO)]2: 6 (95%). Orange crystals were obtained by slow diffusion of pentane into a soln. of
6 in benzene. IR: 1647 (CO). 1H-NMR (400 MHz, CDCl3): 1.26 (t, 3J ˆ 7, 3 MeCH2); 2.58 (q, 3J ˆ 7, 3 MeCH2);
5.11 (s, C6H3); 7.06 ± 7.69 (m, 20 H, Ph). 13C-NMR (101 MHz, CDCl3): 13.63 (MeCH2); 26.41(Me CH2); 68.00 (d,
1
1J(Rh,C) ˆ 12, CÀPh); 73.29 (arom. CH); 93.71( d, J(Rh,C) ˆ 12, CÀPh); 103.38 (arom. C); 127.10 ± 131.74
(Ph); 165.28 (CO). Anal. calc. for C41H38Cl3ORhRu: C 57.46, H 4.47; found: C 57.65, H 4.33.
Tri-m-chloro{[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one]rhodium}[h6-1-
methyl-4-(1-methylethyl)benzene]ruthenium [(p-cymene)Ru(m-Cl)3Rh{h4-Ph2(Nph)2C4CO}]; 7). As described
for 5, with [RuCl2(p-cymene)]2 and [RhCl{h4-Ph2(Nph)2C4CO}]2: 7 (94%). IR: 1636 (CO). 1H-NMR
(400 MHz, CDCl3): 1.31 (d, 3J ˆ 7, Me2CH); 2.18 (s, Me); 2.86 (sept., 3J ˆ 7, Me2CH); 5.28 (d, 3J ˆ 6, 2 arom.
H (cym.)); 5.54 (d, 3J ˆ 6, 2 arom. H (cym.); 7.07 ± 7.65 (m, 24 H, Ph, Nph). 13C-NMR (101 MHz, CDCl3): 18.95,
22.22 (Me); 31.32 (Me2CH); 68.51( d, 1J(Rh,C) ˆ 12, CÀPh); 77.67, 80.29 (CH (cym.)); 93.57 (d, 1J(Rh,C) ˆ 12,
CÀNph); 96.91, 100.13 (C (cym.)); 125.95 ± 132.77 (Ph, Nph); 165.55 (CO). Anal. calc. for C47H38Cl3ORhRu: C
60.76, H 4.12; found: C 60.99, H 4.43.
Tri-m-chloro{[2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one]rhodium}(h6-1,3,5-
triethylbenzene)ruthenium ([(1,3,5-Et3C6H3)Ru(m-Cl)3Rh{h4-Ph2(Nph)2C4CO}]; 8). As described for 5, with
[RuCl2(1,3,5-Et3C6H3)]2 and [RhCl{h4-Ph2(Nph)2C4CO}]2: 8 (95%). Orange crystals were obtained by slow
diffusion of pentane into a soln. of 8 in CH2Cl2. IR: 1661 (CO). 1H-NMR (400 MHz, CDCl3): 1.26 (t, 3J ˆ 7,
3 MeCH2); 2.59 (q, 3J ˆ 7, MeCH2); 5.12 (s, C6H3); 7.10 ± 7.48 (m, 24 H, Ph, Nph). 13C-NMR (101 MHz, CDCl3):
1
1
13.72 (MeCH2); 26.45 (MeCH2); 68.46 (d, J(Rh,C) ˆ 12, CÀPh); 73.14 (arom. CH); 93.39 (d, J(Rh,C) ˆ 12,
CÀNph); 103.53 (arom. C); 125.88 ± 132.74 (Ph, Nph); 165.32 (CO). Anal. calc. for C49H42Cl3ORhRu: C 61.48,
H 4.42; found: C 61.17, H 4.34.
Tri-m-chloro(h5-1,2,3,4,5-pentamethylcyclopenta-2,4-dien-1-yl)[(2,3,4,5-h)-2,3,4,5-tetraphenylcyclopenta-
2,4-dien-1-one]dirhodium ([(Cp*)Rh(m-Cl)3Rh(h4-Ph4C4CO)]; 9). As described for 5, with [RhCl2(Cp*)]2 and

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[RhCl(h4-Ph4C4CO)]2: 9 (95%). Orange crystals were obtained by slow diffusion of pentane into a soln. of 9 in
1
CH2Cl2. IR: 1645 (CO). H-NMR (400 MHz, CDCl3): 1.66 (s, 15 H, Cp*); 7.08 ± 7.75 (m, 20 H, Ph). 13C-NMR
(101 MHz, CDCl3): 9.40 (Cp*); 67.90 (d, 1J(Rh,C) ˆ 12, CÀPh); 93.47 (d, 1J(Rh,C) ˆ 12, CÀPh); 94.29 (d,
1J(Rh,C) ˆ 9, Me5C5); 127.08 ± 131.85 (Ph); 165.15 (CO). Anal. calc. for C39H35Cl3ORh2: C 56.31, H 4.24; found:
C 56.85, H 4.08.
Tri-m-chloro(h5-1,2,3,4,5-pentamethylcyclopenta-2,4-dien-1-yl){[(2,3,4,5-h)-2,3,4,5-tetraphenylcyclopenta-
2,4-dien-1-one]rhodium}iridium ([(Cp*)Ir(m-Cl)3Rh(h4-Ph4C4CO)]; 10). As described for 5, with [IrCl2(Cp*)]2
and [RhCl(h4-Ph4C4CO)]2: 10 (94%). IR: 1650 (CO). 1H-NMR (400 MHz, CDCl3): 1.62 (s, 15 H, Cp*); 7.09 ±
7.76 (m, 20 H, Ph). 13C-NMR (101 MHz, CDCl3): 9.34 (Cp*); 68.41( d, 1J(Rh,C) ˆ 12, CÀPh); 85.66 (s, Me5C5);
93.58 (d, 1J(Rh,C) ˆ 12, CÀPh); 127.24 ± 131.57 (Ph); 164.99 (CO). Anal. calc. for C39H35Cl3IrORh: C 50.85, H
3.83; found: C 50.92, H 3.93.
Tri-m-chloro[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one](h5-1,2,3,4,5-penta-
methylcyclopenta-2,4-dien-1-yl)dirhodium ([(Cp*)Rh(m-Cl)3Rh{h4-Ph2(Nph)2C4CO}]; 11). As described for 5,
with [RhCl2(Cp*)]2 and [RhCl{h4-Ph2(Nph)2C4CO}]2: 11 (95%). IR: 1647 (CO). 1H-NMR (400 MHz, CDCl3):
1.67 (s, 15 H, Cp*); 7.11 ± 7.80 (m, 24 H, Ph, Nph). 13C-NMR (101 MHz, CDCl3): 9.42 (Cp*); 68.36 (d,
1J(Rh,C) ˆ 12, CÀPh); 93.20 (d, 1J(Rh,C) ˆ 12, CÀPh); 94.31( d, 1J(Rh,C) ˆ 9, Me5C5); 125.83 ± 132.77 (Ph,
Nph); 165.31 (CO). Anal. calc. for C47H39Cl3ORh2: C 60.57, H 4.22; found: C 60.96, H 4.53.
Tri-m-chloro{[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one]rhodium}(h5-
1,2,3,4,5-pentamethylcyclopenta-2,4-dien-1-yl)iridium ([(Cp*)Ir(m-Cl)3Rh{h4-Ph2(Nph)2C4CO)]; 12). As de-
scribed for 5, with [IrCl2(Cp*)]2 and [RhCl{h4-Ph2(Nph)2C4CO}]2: 12 (94%). IR: 1650 (CO). 1H-NMR
(400 MHz, CDCl3): 1.64 (s, 15 H, Cp*); 7.10 ± 7.78 (m, 24 H, Ph, Nph). 13C-NMR (101 MHz, CDCl3): 9.37 (Cp*);
68.89 (d, 1J(Rh,C) ˆ 12, CÀPh); 85.69 (s, Me5C5); 93.35 (d, 1J(Rh,C) ˆ 12, CÀNph); 125.94 ± 132.83 (Ph, Nph);
165.17 (CO). Anal. calc. for C47H39Cl3OIrRh: C 55.27, H 3.85; found: C 55.43, H 3.47.
Tricarbonyltri-m-chloro{[(2,3,4,5-h)-2,3,4,5-tetraphenylcyclopenta-2,4-dien-1-one]rhodium}ruthenium
([(CO)3Ru(m-Cl)3Rh(h4-Ph4C4CO)]; 13). As described for 5, with [RuCl2(CO)3]2 and [RhCl(h4-Ph4C4CO)]2:
13 (93%). Orange crystals were obtained by slow diffusion of pentane into a soln. of 13 in CH2Cl2. IR: 1645
(CO), 2003 (MÀCO), 2063 (MÀCO), 2140 (MÀCO). 1H-NMR (400 MHz, CDCl3): 7.14 ± 7.73 (m, 20 H, Ph).
13C-NMR (101 MHz, CDCl3): 69.31( d, 1J(Rh,C) ˆ 12, CÀPh); 94.80 (d, 1J(Rh,C) ˆ 12, CÀPh); 127.97 ± 131.32
(Ph); 165.18 (CO); 182.97 (COÀRu). Anal. calc. for C32H20Cl3O4RhRu: C 49.35, H 2.59; found: C 49.34, H 2.86.
Tricarbonyltri-m-chloro{[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcyclopenta-2,4-dien-1-one]rho-
dium}ruthenium ([(CO)3Ru(m-Cl)3Rh{h4-Ph2(Nph)2C4CO}]; 14). As described for 5, with [RuCl2(CO)3]2 and
[RhCl{h4-Ph2(Nph)2C4CO}]2: 14 (91%). Orange crystals were obtained by slow diffusion of pentane into a soln.
of 14 in CH2Cl2. IR: 1645 (CO), 2008 (MÀCO), 2061(M ÀCO), 2138 (MÀCO). 1H-NMR (400 MHz, CDCl3):
7.18 ± 7.77 (m, 24 H, Ph, Nph). 13C-NMR (101 MHz, CDCl3): 69.73 (d, 1J(Rh,C) ˆ 12, CÀPh); 94.61( d,
1J(Rh,C) ˆ 12, CÀNph); 126.36 ± 133.00 (Ph, Nph); 165.38 (CO); 182.98 (MÀCO). Anal. calc. for
C40H24Cl3O4RhRu: C 54.66, H 2.75; found: C 54.28, H 2.25.
[Butane-1,4-diylbis[dicyclohexylphosphine-kP]]carbonyltri-m-chloro{[(2,3,4,5-h)-2,3,4,5-tetraphenylcyclo-
penta-2,4-dien-1-one]rhodium}rhutenium ([(dcypb)(CO)Ru(m-Cl)3Rh(h4-Ph4C4CO)]; 15). As described for 5,
with [RuCl2(dcypb)(CO)]2 and [RhCl(h4-Ph4C4CO)]2: 15 (90%). Orange crystals were obtained by slow
diffusion of pentane into a soln. of 15 in CH2Cl2. IR: 1643 (CO), 1948 (br., MÀCO). 1H-NMR (400 MHz,
CDCl3): 1.18 ± 2.11 (m, 52 H, dcypb); 7.08 ± 7.83 (m, 20 H, Ph). 13C-NMR (101 MHz, CDCl3): 20.70 ± 40.05 (m,
1
1
dcypb); 67.27 (d, J(Rh,C) ˆ 12, CÀPh); 93.25 (d, J(Rh,C) ˆ 12, CÀPh); 126.68 ± 132.42 (Ph); 164.81 (CO);
201.56 (t, 2J(C,P) ˆ 15, CO). 31P-NMR (162 MHz, CDCl3): 45.99 (s). Anal. calc. for C58H72Cl3O2P2RhRu: C
59.36, H 6.18; found: C 58.97, H 6.24.
[Butane-1,4-diylbis[dicyclohexylphosphine-kP]]carbonyltri-m-chloro{[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-
2,5-diphenylcyclopenta-2,4-dien-1-one]rhodium}ruthenium ([(dcypb)(CO)Ru(m-Cl)3Rh{h4-Ph2(Nph)2C4CO)];
16). As described for 5, with [RuCl2(dcypb)(CO)]2 and [RhCl{h4-Ph2(Nph)2C4CO}]2: 16 (90%). IR: 1638 (CO),
1949 (br., MÀCO). 1H-NMR (400 MHz, CDCl3): 1.22 ± 2.19 (m, 52 H, dcypb); 7.15 ± 8.06 (m, 24 H, Ph, Nph).
13C-NMR (101 MHz, CDCl3): 20.74 ± 25.94 (m, dcypb); 26.18 ± 29.09 (m, dcypb); 37.20 ± 40.75 (m, dcypb); 67.68
1
1
(d, J(Rh,C) ˆ 12, CÀPh); 92.91( d, J(Rh,C) ˆ 12, CÀNph); 125.69 ± 132.61 (Ph, Nph); 164.98 (CO); 201.55
(t, 2J(C,P) ˆ 15, MÀCO). 31P-NMR (162 MHz, CDCl3): 46.31( s). Anal. calc. for C66H76Cl3O2P2RhRu: C 62.24,
H 6.01; found: C 62.24, H 6.08.
[Butane-1,4-diylbis[dicyclohexylphosphine-kP]]tri-m-chloro(propan-2-one){[(2,3,4,5-h)-2,3,4,5-tetraphen-
ylcyclopenta-2,4-dien-1-one]rhodium}ruthenium ([(dcypb)(Me2CO)Ru(m-Cl)3Rh(h4-Ph4C4CO)]; 18). A soln.
of [(dcypb)(N2)Ru(m-Cl)3RuCl(dcypb)] (70 mg, 55 mmol) and [RhCl(h4-Ph4C4CO)]2 (58 mg, 55 mmol) in
CH2Cl2/Me2CO 9 :1(10 ml) was stirred for 30 min. After evaporation, the product was washed with pentane and

Helvetica Chimica Acta ± Vol. 88 (2005)
443
dried under vacuum: 18 (90%). IR: 1646 (br., Me2CO). 1H-NMR (400 MHz, (D6)acetone): 1.21 ± 2.24 (m, 52 H,
dcypb); 7.07 ± 7.90 (m, 20 H, Ph). 13C-NMR (101 MHz, (D6)acetone): 23.42 ± 25.93 (m, dcypb); 28.79 ± 30.44 (m,
dcypb); 39.84 ± 43.47 (m, dcypb); 69.23 (d, 1J(Rh,C) ˆ 12, CÀPh); 95.46 (d, 1J(Rh,C) ˆ 12, CÀPh); 129.05 ±
134.63 (m, Ph); 168.77 (CO). 31P-NMR (162 MHz, (D6)acetone): 42.88 (s). Anal. calc. for C60H78Cl3O2P2RhRu ´
3/2 H2O: C 58.56, H 6.63; found: C 58.24, H 6.99.
[Butane-1,4-diylbis[dicyclohexylphosphine-kP]]tri-m-chloro{[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphen-
ylcyclopenta-2,4-dien-1-one]rhodium}(propan-2-one)ruthenium
([(dcypb)(Me2CO)Ru(m-Cl)3Rh{h4-
Ph2(Nph)2C4CO}]; 19). As described for 18, with [(dcypb)(N2)Ru(m-Cl)3RuCl(dcypb)] and [RhCl{h4-
Ph2(Nph)2C4CO)]2: 19 (95%). IR: 1646 (br., CO, Me2CO). 1H-NMR (400 MHz, (D6)acetone): 1.21 ± 2.26
(m, 52 H, dcypb); 7.09 ± 7.92 (m, 24 H, Ph, Nph). 13C-NMR (101 MHz, (D6)acetone): 21.39 ± 28.68 (m, dcypb);
37.78 ± 39.29 (m, dcypb); 40.36 ± 41.55 (m, dcypb); 67.67 (d, 1J(Rh,C) ˆ 12, CÀPh); 94.15 (d, 1J(Rh,C) ˆ 12,
CÀNph); 126.73 ± 133.37 (m, Ph, Nph); 166.87 (CO). 31P-NMR (162 MHz, (D6)acetone): 43.17 (s). Anal. calc.
for C68H82Cl3O2P2RhRu ´ 1/2 H2O: C 62.22, H 6.37; found: C 62.08, H 6.33.
[Butane-1,4-diylbis[diphenylphosphine-kP]]tri-m-chloro(propan-2-one){[(2,3,4,5-h)-2,3,4,5-tetraphenylcy-
clopenta-2,4-dien-1-one]rhodium}ruthenium ([(dppb)(Me2CO)Ru(m-Cl)3Rh(h4-Ph4C4CO)]; 21). As described
for 18, with [(dppb)ClRu(m-Cl)2(m-OH2)RuCl(dppb)] and [RhCl(h4-Ph4C4CO)]2: 21 (97%). IR: 1644 (br., CO,
Me2CO). 1H-NMR (400 MHz, (D6)acetone): 1.57 (m, CH2); 1.81 (m, CH2); 2.53 (m, CH2); 2.86 (m, CH2);
7.14 ± 7.92 (m, 40 H, Ph). 13C-NMR (101 MHz, (D6)acetone): 23.71( s, CH2 (dppb)); 31.77 ± 32.08 (m, CH2
(dppb)); 66.82 (d, 1J(Rh,C) ˆ 12, CÀPh); 93.83 (d, 1J(Rh,C) ˆ 12, CÀPh); 127.16 ± 139.94 (m, Ph); 166.73
(CO); 227.10 (Me2CO). 31P-NMR (162 MHz, (D6)acetone): 47.59 (s). Anal. calc. for C60H54Cl3O2P2RhRu ´
2 H2O: C 59.29, H 4.81; found: C 59.09, H 4.95.
[Butane-1,4-diylbisdiphenylphosphine-kP]]tri-m-chloro{[(2,3,4,5-h)-3,4-dinaphthalen-2-yl-2,5-diphenylcy-
clopenta-2,4-dien-1-one]rhodium}(propan-2-one)ruthenium ([(dppb)(Me2CO)Ru(m-Cl)3Rh{h4-Ph2(Nph)2-
Table 2. Crystallographic Data for the Complexes 5 and 8
5
8 ´ CH2Cl2
Empirical formula
Molar mass [g molÀ1
Crystal size [mm]
Crystal system
Space group
a [Š]
C39H34Cl3ORhRu
828.99
C50H44Cl5ORhRu
1042.08
]
0.13 Â 0.12 Â 0.11
0.15 Â 0.14 Â 0.12
triclinic
triclinic
Å
Å
P1
P1
11.1058(9)
12.458(3)
b [Š]
11.771(3)
13.679(3)
c [Š]
13.387(3)
15.190(2)
a [8]
b [8]
g [8]
78.40(2)
81.021(12)
88.492(12)
1693.2(6)
115.542(18)
105.835(17)
97.518(19)
2152.9(8)
2
Volume [Š3]
Z
2
Density [g cmÀ3
]
1.626
1.608
Temperature [K]
140(2)
1.201
140(2)
1.083
3.01± 25.03
Absorption coefficient [nmÀ1
V range [8]
]
2.97 ± 25.03
À 12 ! 11, À 14 ! 14, À 15 ! 15
10966
5597 (Rint ˆ 0.0295)
semi-empirical
0.9168 and 0.8131
5597/0/407
Index ranges
À 14 ! 14, À 16 ! 16, À 17 ! 18
Reflections collected
Independent reflections
Absorption correction
Max. and min. transmission
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices (I > 2s(I)
14025
7141 (Rint ˆ 0.0366)
semi-empirical
0.9468 and 0.8180
7141/6/581
1.119
1.136
R1 ˆ 0.0354, wR2 ˆ 0.0966
R1 ˆ 0.0428, wR2 ˆ 0.1047
0.606/ À 0.659
R1 ˆ 0.0479, wR2 ˆ 0.1331
R1 ˆ 0.0560, wR2 ˆ 0.1427
1.504/À 0.719
R indices (all data)
Largest diff. peak/hole [eŠ
À3
]

444
Helvetica Chimica Acta ± Vol. 88 (2005)
C4CO)]; 22). As described for 18, with [(dppb)ClRu(m-Cl)2(m-OH2)RuCl(dppb)] and [RhCl{h4-
Ph2(Nph)2C4CO)]2: 22 (90%). Orange crystals were obtained by slow diffusion of pentane into a soln. of 22
in CH2Cl2/acetone. IR: 1643 (br., CO, Me2CO). 1H-NMR (400 MHz, (D6)acetone): 1.53 (m, CH2); 1.79 (m,
CH2); 2.53 (m, CH2); 2.91( m, CH2); 7.13 ± 8.25 (m, 44 H, Ph, Nph). 13C-NMR (101 MHz, (D6)acetone): 23.66 (s,
CH2 (dppb)); 31.71 ± 32.02 (m, CH2 (dppb)); 67.22 (d, 1J(Rh,C) ˆ 12, CÀPh); 93.89 (d, 1J(Rh,C) ˆ 12, CÀNph);
126.76 ± 133.93 (m, Ph, Nph); 166.87 (CO). 31P-NMR (162 MHz, (D6)acetone): 47.64 (s). Anal. calc. for
C68H58Cl3O2P2RhRu: C 63.83, H 4.57; found: C 63.32, H 4.25.
Crystallographic Investigations. The relevant details of the crystals, data collection, and structure
refinement are listed in the Tables 2 ± 4. Diffraction data were collected by using the MoKa radiation on
different equipment: Oxford-Diffraction diffractometer with a kappa geometry and equipped with a Sapphire-
CCD detector (for 9, 15, and 22) or a mar345-imaging-plate detector (for 5, 8, and 13). Data reduction and cell
refinement were performed with CrysAlis RED 1.6.9 [19]. Absorption correction was applied to all data sets by
using a semi-empirical method (MULTI-SCAN) [20]. Structure solutions were determined with ab initio direct
methods [21]. All structures were refined by full-matrix least-squares on F2 with all non-H-atoms anisotropically
defined. The H-atoms were placed in calculated positions by using the ꢁriding modelꢂ with Uiso ˆ a ´ Ueq(C)
(where a is 1.5 for Me H-atoms and 1.2 for others, C is the parent C-atom). Space-group determination,
structure refinement, and geometrical calculations were carried out with all structures by the SHELXTL
software package, release 5.1[22]. CCDC-254057 ± CCDC-254062 contain supplementary crystallographic data
for 5, 8, 9, 13, 15, and 22. These data can be obtained free of charge via www.ccdc.cam.ac.uk/const/
retrieving.html (or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB21EZ,
UK; fax: (‡44)1223-336-033; or deposit@ccdc.cam.ac.uk).
Table 3. Crystallographic Data for the Complexes 9 and 13
9 ´ CH2Cl2
13
Empirical formula
Molar mass [g molÀ1
Crystal size [mm]
Crystal system
Space group
a [Š]
C40H37Cl5ORh2
916.77
C32H20Cl3O4RhRu
778.81
]
0.16 Â 0.13 Â 0.10
0.16 Â 0.10 Â 0.10
triclinic
triclinic
Å
Å
P1
P1
10.3109(5)
10.177(3)
b [Š]
c [Š]
a [8]
12.6523(11)
15.8881(10)
80.926(6)
10.353(4)
16.081(4)
94.32(3)
b [8]
81.670(5)
95.67(2)
g [8]
66.784(6)
1872.7(2)
2
118.49(3)
1467.3(8)
2
Volume [Š3]
Z
Density [g cmÀ3
]
1.626
1.763
Temperature [K]
140(2)
1.269
3.23 ± 25.03
140(2)
1.387
Absorption coefficient [nmÀ1
V range [8]
]
3.18 ± 25.02
À 12 ! 12, À 11 ! 11, À 19 ! 19
9579
4865 (Rint ˆ 0.0522)
semi-empirical
0.9764 and 0.7011
4865/0/371
Index ranges
À 12 ! 12, À 14 ! 15, À 18 ! 18
Reflections collected
Independent reflections
Absorption correction
Max. and min. transmission
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices (I > 2s(I)
11363
5775 (Rint ˆ 0.0297)
semi-empirical
0.8724 and 0.7533
5775/0/443
0.936
1.165
R1 ˆ 0.0246, wR2 ˆ 0.0526
R1 ˆ 0.0370, wR2 ˆ 0.0549
0.519/ À 0.589
R1 ˆ 0.0518, wR2 ˆ 0.1391
R1 ˆ 0.0603, wR2 ˆ 0.1551
1.573/À 1.629
R indices (all data)
Largest diff. peak/hole [eŠ
À3
]

Helvetica Chimica Acta ± Vol. 88 (2005)
445
Table 4. Crystallographic Data for the Complexes 15 and 22
15 ´ 2 CH2Cl2
22 ´ 3 acetone
Empirical formula
Molar mass [g molÀ1
Crystal size [mm]
Crystal system
Space group
a [Š]
b [Š]
c [Š]
a [8]
b [8]
C60H76Cl7O2P2RhRu
1343.28
C77H76Cl3O5P2RhRu
1453.65
]
0.22 Â 0.18 Â 0.17
0.20 Â 0.14 Â 0.13
monoclinic
triclinic
Å
Cc
P1
21.8005(14)
17.5088(15)
16.7048(14)
90
105.911(6)
90
6132.0(8)
4
12.8812(9)
13.9637(8)
20.4804(14)
74.782(5)
72.973(6)
86.223(5)
3398.6(4)
2
g [8]
Volume [Š3]
Z
Density [g cmÀ3
]
1.455
1.421
Temperature [K]
Absorption coefficient [nmÀ1
V range [8]
140(2)
0.913
3.14 ± 25.03
140(2)
0.681
3.16 ± 25.03
]
Index ranges
À 25 ! 25, À 20 ! 20, À 17 ! 19
À 14 ! 14, À 16 ! 16, À 24 ! 24
Reflections collected
Independent reflections
Absorption correction
Max. and min. transmission
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices (I > 2s(I)
17986
20176
9852 (Rint ˆ 0.0440)
semi-empirical
0.8773 and 0.7968
9852/8/670
10509 (Rint ˆ 0.0376)
semi-empirical
0.9326 and 0.8260
10509/8/766
0.932
0.987
R1 ˆ 0.0448, wR2 ˆ 0.0916
R1 ˆ 0.0582, wR2 ˆ 0.0954
1.041/À 0.704
R1 ˆ 0.0455, wR2 ˆ 0.1216
R1 ˆ 0.0629, wR2 ˆ 0.1299
1.277/À 1.071
R indices (all data)
Largest diff. peak/hole [eŠ
À3
]
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Received October 30, 2004