Supported organometallic complexes part XXXV. Synthesis, characterization, and catalytic application of a new family of diamine(diphosphine)ruthenium(II) complexes

Article abstract of DOI:10.1016/S0022-328X(02)02112-5

The novel diamine(dppp)ruthenium(II) complexes 3L₁-3L₁₂ have been obtained by reaction of equimolar amounts of Cl₂Ru(dppp)₂ (2) with the diamines L₁-L₁₂ in excellent yields. Within a few minutes one of the diphosphine ligands was quantitatively exchanged by the corresponding diamine. X-ray structural investigations of 3L₁, 3L₂, and 3L₈ show triclinic unit cells with the space groups P1? (3L₁, 3L₂) and P 1 (3L₈). Whereas in solution all these complexes prefer a trans-RuCl₂ configuration, in the solid state cis-(3L₁, 3L₂) and trans-isomers (3L₈) were observed. With the exception of 3L₅, 3L₆, and 3L₁₂ all mentioned ruthenium complexes are highly catalytically active in the hydrogenation of the α, β-unsaturated ketone trans-4-phenyl-3-butene-2-one. In most cases the conversions and selectivities toward the formation of the unsaturated alcohol trans-4-phenyl-3-butene-2-ol were >99% with high turnover frequencies (TOFs) under mild conditions.

Full text of DOI:10.1016/S0022-328X(02)02112-5

Journal of Organometallic Chemistry 665 (2003) 176ꢀ185
/
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Supported organometallic complexes
Part XXXV. Synthesis, characterization, and catalytic application of
a new family of diamine(diphosphine)ruthenium(II) complexesꢀ
Ekkehard Lindner *, Hermann A. Mayer *, Ismail Warad, Klaus Eichele
Institut fur Anorganische Chemie der Universitat Tubingen, Auf der Morgenstelle 18, D-72076 Tubingen, Germany
¨ ¨ ¨ ¨
Received 24 July 2002; accepted 30 October 2002
Abstract
The novel diamine(dppp)ruthenium(II) complexes 3L1ꢀ
Cl2Ru(dppp)2 (2) with the diamines L1ꢀ
quantitatively exchanged by the corresponding diamine. X-ray structural investigations of 3L1, 3L2, and 3L8 show triclinic unit cells
/
3L12 have been obtained by reaction of equimolar amounts of
/L12 in excellent yields. Within a few minutes one of the diphosphine ligands was
¯
with the space groups P1 (3L1, 3L2) and P 1 (3L8). Whereas in solution all these complexes prefer a trans-RuCl2 configuration, in
/
the solid state cis-(3L1, 3L2) and trans-isomers (3L8) were observed. With the exception of 3L5, 3L6, and 3L12 all mentioned
ruthenium complexes are highly catalytically active in the hydrogenation of the a,b-unsaturated ketone trans-4-phenyl-3-butene-2-
one. In most cases the conversions and selectivities toward the formation of the unsaturated alcohol trans-4-phenyl-3-butene-2-ol
were ꢀ99% with high turnover frequencies (TOFs) under mild conditions.
/
# 2002 Elsevier Science B.V. All rights reserved.
Keywords: Ruthenium(II) complexes; Crystal structures; Diphos ligand; Diamine ligands; Catalytic hydrogenation
1. Introduction
erally, the most widely accepted theory is that at least
one NH and a RuH unit is intimately involved in the
hydride transfer process [8,13]. It has been considered
that the catalytic activity is traced back to the electronic
properties of the coordination center and that the
stereoselectivity is controlled by the chiral ligand [13].
Similar catalyst systems were established by Burk,
The hydrogenation of carbonyl compounds to alco-
hols is among the most applied processes in organic
chemistry [2ꢀ5]. Recently Noyori et al. discovered a
/
ruthenium(II) complex system containing diphosphine
and 1,2-diamine ligands which, in the presence of a base
and 2-propanol, proved to be excellent catalysts for the
Bergens, and Morris et al. [15ꢀ18]. In the last mentioned
/
hydrogenation of ketones under mild conditions [6ꢀ8].
/
case the authors used mono- and dihydride(diamine)(di-
phos)ruthenium(II) complexes and found that in the
absence of a base no hydrogenation of the carbonyl
group has taken place [17].
Subsequently chiral ruthenium(II) complexes were de-
veloped for the asymmetric hydrogenation of functio-
nalized ketones [8ꢀ12]. If these complexes are supported
/
no leaching takes place and the activity and enantio-
selectiveity remained constant even after twelve runs
[11]. A mechanism of this reaction has been suggested
[7,10,13,14]. The source of the transferred hydrogen
atom was attributed to a metal-centered hydride. Gen-
In a recent work we reported on the preparation of
novel diamineruthenium(II) complexes which were pro-
vided with hemilabile etherꢀphosphine ligands [1,19].
/
These complexes proved to be excellent catalysts in the
hydrogenation of a,b-unsaturated ketones [1]. By the
introduction of T-silyl functions into the etherꢀ
phine ligands, these complexes can be supported to a
polysiloxane matrix after a solꢀgel process [20]. Now we
/
phos-
ꢀ For Part XXXIV see Ref. [Inorg. Chim. Acta (in press)].
* Corresponding authors. Tel.: ꢁ
/
49-7071-29-72039; fax: ꢁ49-7071-
/
/
29-5306
E-mail addresses: ekkehard.lindner@uni-tuebingen.de (E. Lindner),
hermann.mayer@uni-tuebingen.de (H.A. Mayer).
introduce a facile and fast synthesis of a series of
diamine(diphos)ruthenium(II) complexes. As a diphos
0022-328X/02/$ - see front matter # 2002 Elsevier Science B.V. All rights reserved.
PII: S 0 0 2 2 - 3 2 8 X ( 0 2 ) 0 2 1 1 2 - 5

E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ
/
185
177
ligand 1,3-bis(diphenylphosphino)propane was selected,
because in a subsequent investigation it can be attached
to a spacer unit at the symmetric carbon atom 2 of the
ligand backbone [21,22]. Three complexes (3L1, 3L2, and
3L8) were subjected to an X-ray structural investigation.
Most of the complexes are highly active in the catalytic
hydrogenation of trans-4-phenyl-3-butene-2-one.
methane, the yellow, somewhat air-insensitive mixed
diamine[bis(diphenylphosphino)propane]ruthenium(II)
complexes 3L1ꢀ3L12 were formed in good to excellent
/
yields. Even in the presence of excess diamine only one
dppp ligand was exchanged (Scheme 1). The yields of
the complexes 3L1ꢀ3L12 depend on steric factors of the
/
diamine ligands. If one or both hydrogen atoms at the
nitrogen donors are replaced by alkyl or aryl groups no
reaction takes place. Bipyridine and other aromatic N-
derivatives do not react with complex 2, even under
2. Results and discussion
elevated conditions. Complexes 3L1ꢀ3L12 are soluble in
/
chlorinated organic solvents and insoluble in ethers and
aliphatic hydrocarbons. Their molecular composition
was corroborated by FAB mass spectra.
2.1. Synthesis of the
diamine[bis(diphenylphosphino)propane]ruthenium(II)
complexes 3L1ꢀ3L12
/
The precursor compound trans-Cl2Ru(dppp)2 (2) was
obtained by a substitution reaction starting from
Cl2Ru(PPh3)3 (1) and dppp in dichloromethane [23]. If
2.2. NMR and IR spectroscopic investigations
1
In the H-NMR spectra of the diamine(dppp)ruthe-
2 is treated with the diamines L1ꢀ/L12 in dichloro-
nium(II) complexes 3L1ꢀ3L12 characteristic sets of
/
Scheme 1.

178
E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ185
/
complex only in the number and kind of substituents at
the carbon backbone. While the bis(phosphine) ring
allows for PÃ
of 908, the smaller diamine enforces NÃ
that are 9ꢀ138 less than the ideal value. The most
/
RuÃ
/
P angles very close to the ideal value
/
RuÃN angles
/
/
striking difference between the three complexes is the
finding that 3L1 and 3L2 form the cis-chloro isomer II
(Chart 1), while 3L8 crystallizes as the more usual trans-
chloro isomer I, although all three compounds were
shown by spectroscopic methods to be the trans-chloro
isomer in solution (vide supra).
Chart 1.
signals were observed, which are attributed to the
phosphine and diamine ligands. Their assignment was
supported by two-dimensional H,H-COSY experiments,
which establish the connectivity between NH2 and CH2
functions in the diamine ligands, as well as between CH2
and CH2P groups in the phosphine fragments. The
integration of the 1H resonances confirm that the
phosphine to diamine ratios are in agreement with the
The structure of 3L1 is similar to that of a bis(etherꢀ
/
phosphine)ruthenium complexes, (en)(H3COCH2CH2P-
Ph2)2RuCl2, described earlier [19]: the RuÃ
/
P and RuÃ
/
N
distances trans to chlorine are slightly shorter than those
trans to nitrogen or phosphorus, respectively. Similarly,
compositions of 3L1ꢀ
served in the 31P{1H}-NMR spectra of the
RuCl2(dppp)diamine complexes 3L1, 3L4, 3L5, 3L7ꢀ
/
3L12. Because singlets are ob-
the RuÃ
/
Cl distances trans to nitrogen are slightly
shorter than those trans to phosphorus. The diamine
chelate prefers the twist conformation, with C(28) 0.24
/
3L10, and 3L12 the C1 symmetric structure II in Chart
1 is ruled out. In the cases of 3L2, 3L3, and 3L11 the
asymmetric diamines cause a loss of the C2-axis which
results in a splitting of the 31P resonances into AB
patterns. However, in 3L6 this asymmetry is too remote
from the phosphorus atoms to generate an observable
splitting of the 31P{1H}-NMR signal. The 31P chemical
˚
˚
A below and C(29) 0.42 A above the N(1)Ã
/
Ru(1)Ã
/
N(2)
plane. Fig. 1 and the data in Table 1 indicate that the
structure of 3L2 is quite similar to that of 3L1, albeit the
former cocrystallizes with one molecule of dichloro-
methane. It appears that, otherwise, the methyl sub-
stituent at C(28) exerts little effect on the stuctural
parameters, although the twist conformation of the
shifts and the 31PÃ
/
31P coupling constants are consistent
diamine is more regular, with C(28) and C(29) displaced
˚
with a cis arrangement of the P groups according to
structure I (Chart 1).
by ꢂ
/
0.32 and 0.33 A below and above the N(1)Ã
/
Ru(1)Ã
/
N(2) plane. In contrast, the phenyl substituents of the
diamine in 3L8 cause a change in the symmetry of the
complex: 3L8 crystallizes as the trans-chloro isomer with
two independent molecules in the asymmetric unit. Both
molecules are arranged about a pseudo-inversion center
that approximately maps the greater part of molecule A
to molecule B, except for the S,S-configuration of the
diamine ligand that does not allow for a centrosym-
metric space group. In addition, the diamine chelates
adopt slightly different conformations: in molecule B it
Characteristic sets of resonances between 15ꢀ
35ꢀ
49 ppm are found in the 13C{1H}-NMR spectra of
3L1ꢀ3L12, which are attributed to the aliphatic part of
the phosphine and diamine ligands, respectively. AXX?
splitting patterns were observed for the aliphatic and
aromatic carbon atoms directly attached to phosphorus.
They are caused by the interaction of the magnetically
inequivalent phosphorus atoms with the 13C nuclei. This
pattern is also consistent with structure I (Chart 1).
/
30 and
/
/
The IR spectra of the complexes 3L1ꢀ
particular show four sets of characteristic absorptions
in the ranges 3336ꢀ3319, 3268ꢀ3215, 3178ꢀ3165, and
275ꢀ
254 cmꢂ1, which can be assigned to NH2, amineÃ
CH, phosphineÃCH and RuCl stretching vibrations,
respectively.
/3L12 in
is the normal twist conformation, with C(28B) and
˚
C(29B) by 0.31 and ꢂ
/
0.50 A above and below the NÃ
/
/
/
/
RuÃ
/
N plane, but in A it is close to an envelope with
/
/
C(29A) at the top: C(28A) and C(29A) are displaced by
˚
/
ꢂ
/
0.07 and 0.59 A from the NÃ
/
RuÃ/N plane.
2.4. Catalytic activity of the ruthenium(II) complexes
3L1ꢀ3L12 in the hydrogenation of trans-4-phenyl-3-
butene-2-one
2.3. X-ray structural determination of 3L1, 3L2, and 3L8
/
Crystals suitable for X-ray structural analysis have
been obtained for complexes 3L1, 3L2, and 3L8. Their
molecular structures are shown in Fig. 1 and selected
bond distances, bond angles, and torsion angles are
listed in Table 1. All three compounds feature two
different chelate systems: a six-membered bis(pho-
sphine) ring that is common to all three and adopts a
similar chair conformations in each case, and a five-
membered diamine ring that differs from complex to
To study the catalytic activity of the ruthenium(II)
complexes 3L1ꢀ3L12, trans-4-phenyl-3-butene-2-one
/
was selected as a model substrate for different reasons:
(i) the hydrogenation of a,b-unsaturated ketones is not
that easy, because of the conformational flexibility of
the substrates [2]; (ii) the ketone reveals UV activity,
which disappears upon hydrogenation of the ketone due
to interruption of the conjugation. This effect can be

E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ
/
185
179
Fig. 1. ORTEP plots of 3L1 (a), 3L2 (b) and the two crystallographically nonequivalent molecules of 3L8 (c) with atom labeling scheme. Thermal
ellipsoids are drawn at the 20% probability level, hydrogens and solvent molecules are omitted for clarity.

180
E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ185
/
Table 1
˚
Selected bond lengths (A) and bond and torsion angles (8) for 3L1, 3L2, and molecules A and B of 3L8
3L1
3L2
3L8, A
3L8, B
Bond lengths
Ru(1)ÃCl(1)
Ru(1)ÃCl(2)
Ru(1)ÃP(1)
Ru(1)ÃP(2)
Ru(1)ÃN(1)
Ru(1)ÃN(2)
2.404(2)
2.466(2)
2.2321(18)
2.2820(14)
2.172(2)
2.147(3)
2.4208(8)
2.5103(10)
2.2440(10)
2.2769(8)
2.1629(19)
2.1333(18)
2.4293(10)
2.4164(11)
2.2563(12)
2.2652(12)
2.171(4)
2.4227(11)
2.4122(11)
2.2640(12)
2.2518(12)
2.183(4)
2.172(4)
2.193(4)
Bond angles
Cl(1)ÃRu(1)ÃCl(2)
P(1)ÃRu(1)ÃP(2)
N(1)ÃRu(1)ÃN(2)
N(1)ÃRu(1)ÃCl(1)
N(2)ÃRu(1)ÃCl(1)
P(1)ÃRu(1)ÃCl(1)
P(2)ÃRu(1)ÃCl(1)
N(1)ÃRu(1)ÃCl(2)
N(2)ÃRu(1)ÃCl(2)
P(1)ÃRu(1)ÃCl(2)
P(2)ÃRu(1)ÃCl(2)
89.13(9)
91.67(6)
80.80(10)
86.11(8)
166.24(6)
87.89(9)
91.48(5)
80.85(8)
84.66(10)
174.25(2)
93.32(6)
91.98(3)
90.88(3)
79.87(7)
84.71(6)
164.14(5)
87.94(3)
90.95(3)
83.24(6)
82.62(6)
177.88(2)
91.24(3)
165.80(4)
89.21(4)
78.07(14)
83.75(11)
89.23(10)
88.53(4)
90.70(4)
83.07(11)
82.89(10)
98.04(4)
101.91(4)
167.15(4)
89.35(4)
77.28(14)
87.97(11)
83.99(11)
89.78(4)
89.07(4)
84.19(11)
84.37(11)
101.25(4)
97.54(4)
Torsion angles
P(2)ÃRu(1)ÃP(1)ÃC(13)
Ru(1)ÃP(1)ÃC(13)ÃC(14)
P(1)ÃC(13)ÃC(14)ÃC(15)
C(13)ÃC(14)ÃC(15)ÃP(2)
C(14)ÃC(15)ÃP(2)ÃRu(1)
C(15)ÃP(2)ÃRu(1)ÃP(1)
N(2)ÃRu(1)ÃN(1)ÃC(28)
Ru(1)ÃN(1)ÃC(28)ÃC(29)
N(1)ÃC(28)ÃC(29)ÃN(2)
C(28)ÃC(29)ÃN(2)ÃRu(1)
C(29)ÃN(2)ÃRu(1)ÃN(1)
40.48(10)
ꢂ61.45(18)
72.2(2)
44.08(9)
ꢂ63.64(16)
71.1(2)
49.65(16)
ꢂ65.1(3)
68.6(4)
46.73(16)
ꢂ50.41(17)
65.1(5)
ꢂ69.4(3)
55.51(19)
ꢂ38.22(10)
ꢂ10.06(18)
35.2(3)
ꢂ68.3(2)
55.55(18)
ꢂ39.71(8)
ꢂ13.47(16)
37.6(3)
ꢂ67.0(5)
59.9(3)
ꢂ68.3(5)
66.3(4)
ꢂ46.34(17)
2.8(2)
ꢂ50.41(17)
13.1(2)
ꢂ28.7(3)
49.0(3)
ꢂ43.9(3)
61.5(3)
ꢂ52.1(3)
41.9(3)
ꢂ50.8(3)
38.9(2)
ꢂ47.3(3)
24.9(2)
ꢂ50.3(3)
20.7(2)
ꢂ17.43(17)
ꢂ13.88(16)
used to carry out kinetic investigations [24]; (iii) the
chosen ketone allows to study the selectivity of the
catalysts. Three different possibilities of the hydrogena-
tion process are to be expected (Scheme 2). The selective
hydrogenation of the carbonyl function affords the
corresponding unsaturated alcohol trans-4-phenyl-3-
butene-2-ol A, which is the most desired product.
Unwanted and hence of minor interest is the hydro-
out under mild conditions at three bar H2 pressure and
35 8C. Results are listed in Table 2.
As expected RuCl2(dppp)2 (2) was completely inactive
in the hydrogenation of unsaturated ketones, which is
traced back to the absence of the diamine. The starting
complex RuCl2(PPh3)2 (1) was only slightly active under
the applied mild reaction conditions. However, the
selectivity was low, because both the CÄ
/
O and CÄ
/
C
functions were hydrogenated to give C with a conversion
of only 28% (Table 2). With the exception of 3L5, 3L6,
genation of the CÄ
saturated ketone B. Also not in the focus of our interest
is the hydrogenation of both the CÄO and CÄC bonds,
/C double bond, leading to the
and 3L12 all ruthenium(II) complexes (3L1ꢀ
3L11) revealed high activity and excellent selectivity. In
the case of 3L1, 3L4, 3L7ꢀ3L9, and 3L11, a conversion of
/
3L4, 3L7ꢀ
/
/
/
resulting in the formation of the saturated alcohol C. 2-
Propanol served as a solvent, but the catalysts were only
active in the presence of excess hydrogen and a
cocatalyst (e.g. KOH). All hydrogenations were carried
/
100% has been achieved in less than 1 h, and the only
product was A (Table 2). If one or two methyl groups
are introduced into the backbone of 1,2-diamines, a
Scheme 2.

E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ
/
185
181
Table 2
Hydrogenation of trans-4-phenyl-3-butene-2-one
mild conditions. In most cases the selectivity was 100%
toward the hydrogenation of only the carbonyl group.
Interestingly complex 3L11 with 1,3-diamine as a ligand
was more active than 1,2-diamine complexes, which has
never been observed.
a
b
c
b
Run Catalyst Conversion (%)
TOF
Selectivity (%)
A
B
C
d
1
2
1
28
0
12
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
100
0
d
2
3
3L1
3L2
3L3
3L4
3L5
3L6
3L7
3L8
3L9
3L10
3L11
3L12
100
90
54
100
1080
776
540
1210
18
100
100
100
100
0
0
4. Experimental
4
0
5
0
6
0
4.1. General remarks, materials, and instrumentations
e
7
28
0
100
0
d
8
0
0
All reactions were carried out in an inert atmosphere
(argon) by using standard high vacuum and Schlenk-line
techniques unless otherwise noted. Prior to use CH2Cl2,
n-hexane, and Et2O were distilled from CaH2, LiAlH4,
9
100
100
100
92
1490
1724
926
920
2000
17
100
100
100
100
100
45
0
10
11
12
13
14
0
0
0
100
25
0
55
e
and from sodiumꢀbenzophenone, respectively.
/
1,3-Bis(diphenylphosphino)propane (dppp) was pre-
pared according to literature methods [25]. The diamines
were purchased from Acros, Fluka, and Merck and had
to be purified by distillation and recrystallization,
a
Reaction was conducted at 35 8C using 3ꢀ5 g of substrate (S/
/
Cꢃ1000) in 50 ml of 2-propanol, PH ꢃ3 bar, [Ru: KOH: Sub-
strate][1:10:1000].
2
b
Yields and selectivities were determined by GC.
hꢂ1).
c
d
e
ꢂ1
cat
respectively. Ph3P, n-BuLi, and RuCl3×
/
3 H2O were
TOF: turnover frequency (molsub mol
Overnight reaction.
15 h reaction.
available from Merck and ChemPur, respectively, and
were used without further purification. Elemental ana-
lyses were carried out on an Elementar Varrio EL
1
analyzer. High-resolution H, 13C{1H}, DEPT 135, and
constant decrease of the turnover frequencies (TOFs)
and the conversions was observed, which is probably
due to steric effects (Table 2 and Fig. 2).
31P{1H}-NMR spectra were recorded on a Bruker DRX
250 spectrometer at 298 K. Frequencies are as follows:
1H-NMR 250.12 MHz, 13C{1H}-NMR 62.9 MHz, and
1
31P{1H}-NMR 101.25 MHz. Chemical shifts in the H
3. Conclusion
and 13C{1H}-NMR spectra were measured relative to
partially deuterated solvent peaks which are reported
relative to TMS. 31P chemical shifts were measured
relative to 85% H3PO4. IR data were obtained on a
Bruker IFS 48 FTIR spectrometer. Mass spectra: EIMS,
Finnigan TSQ70 (200 8C) and FABMS, Finnigan 711A
(8 kV), modified by AMD and reported as mass/charge
(m/z). The analyses of the hydrogenation experiments
were performed on a GC 6000 Vega Gas 2 (Carlo Erba
Instrument) with a FID and capillary column PS 255 [10
In this work a set of 12 (dppp)ruthenium(II) com-
plexes with different aliphatic 1,2-, 1,3-, 1,4-, cycloali-
phatic and aromatic 1,2-diamines as well as chiral
aliphatic 1,2-diamines have been made accessible by a
new method of fast ligand exchange. While in solution
all these complexes prefer a trans-RuCl2 configuration,
in the solid state cis- and trans- isomers were formed.
With exception of the complexes with aromatic diamines
all other species were highly active catalysts in the
m, carrier gas, He (40 kPa), integrator 3390 A (Hewlettꢀ
/
hydrogenation of trans-PhCHÄ/CHC(O)Me even under
Packard)].
Fig. 2. Ruthenium-catalyzed hydrogenation of trans-4-phenyl-3-butene-2-one. PÃ
/
P$
/
is RuCl2(diphos)diamine, PÃ
/
O$
/
RuCl2(etherꢀphosphi-
/
ne)2diamine [1]. Reaction conditions: 2-propanol, KOH as cocatalyst, Tꢃ35 8C and PH
/
ꢃ/3 bar.
2

182
E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ185
/
4.2. General procedure for the preparation of the
complexes 3L1ꢀ3L12 (see Scheme 1)
7.63 (m, 20H, C6H5). 31P{1H}-NMR (CDCl3): d (ppm)
2
41.59, 42.32 (AB pattern, JPP
/
ꢃ
52.20 Hz). 13C{1H}-
/
NMR (CDCl3): d (ppm) 19.44 (s, CH2), 25.43 (dd,
3
4.4, JPC
1
4.4 Hz, PCH2) 25.74 (dd, JPC
4.4 Hz, PCH2), 29.36 (s, CH3), 53.17 (s, NC),
The corresponding diamine (10% excess of L1ꢀ
/
L12)
1JPC
3JPC
ꢃ
ꢃ
/
ꢃ
/
ꢃ4.4,
/
was dissolved in 10 ml of dichloromethane and the
solution was added dropwise to a stirred solution of 2 in
10 ml of dichloromethane within 5 min. The mixture
/
54.58 (s, NCH2), 126.69 (m, m-C6H5), 127.75 (m, p-
C6H5), 131.79 (m, o-C6H5), 136.44 (m, i-C6H5).
FABMS; (m/z): 672.1 [Mꢁ]. Found: C, 55.36; H, 5.69;
Cl, 10.54; N, 4.17. Calc. for C31H38Cl2N2P2Ru: C,
54.90; H, 5.33; Cl, 10.42; N, 4.11%.
was stirred for ca. 10ꢀ30 min at room temperature while
/
the color changed from brown to yellow. After removal
of any turbidity by filtration (P4), the volume of the
solution was concentrated to about 5 ml under reduced
pressure. Addition of 40 ml of diethyl ether caused
precipitation of a solid, which was filtered (P4). After
4.2.4. 3L4
Complex 2 (500 mg, 0.50 mmol) was treated with L4
recrystallization from dichloromethaneꢀn-hexane, the
/
(0.060 g, 0.55 mmol) to give 3L4. Yield 348 mg (99%) of
1
corresponding complexes were obtained in analytically
pure form.
a yellowꢀ
/
brown powder, m.p. 298 8C (dec.). H-NMR
(CDCl3): d (ppm) 0.88ꢀ
/
2.14 (m, 10H, C6H10), 1.81 (m,
2H, CH2), 2.49ꢀ
/
2.81 (m, 8H, PCH2, NH2), 7.12ꢀ
/
7.66
(m, 20H, C6H5). 31P{1H}-NMR (CDCl3): d (ppm)
41.63. 13C{1H}-NMR (CDCl3): d (ppm) 19.31 (s,
4.2.1. 3L1
Complex 2 (500 mg, 0.50 mmol) was treated with L1
(0.035 ml, 0.55 mmol) to give 3L1. Yield 312 mg (97%)
of a yellow powder, m.p. 310 8C (dec.). 1H-NMR
(CDCl3): d (ppm) 1.82 (m, 2H, CH2), 2.74 (br, 12H,
CH2), 24.96 (s, CH2CH2CH), 26.15 (m [26]a, Nꢃ
/
35.02 Hz, PCH2), 36.39 (s, NCHCH2), 57.62 (s,
NCHCH2), 128.16 (m, m-C6H5), 129.15 (m, p-C6H5),
133.11 (m, o-C6H5). FABMS; (m/z): 698.1 [Mꢁ]. Anal.
Found: C, 56.73; H, 5.77; Cl, 10.15; N, 4.01. Calc. for
C33H40Cl2N2P2Ru: C, 56.48; H, 5.76; Cl, 10.03; N,
4.07%.
PCH2, NH2, NCH2), 7.17ꢀ7.60 (m, 20H, C6H5).
/
31P{1H}-NMR (CDCl3): d (ppm) 41.30. 13C{1H}-
NMR (CDCl3): d (ppm) 19.23 (s, CH2), 26.1 (m [26]a,
Nꢃ/35.02 Hz, PCH2), 43.64 (s, NCH2), 128.32 (m [26]b,
Nꢃ
/
8.08 Hz, m-C6H5), 129.20 (s, p-C6H5), 133.13 (br,
o-C6H5). FABMS; (m/z): 644.1 [Mꢁ]. Anal. Found: C,
54.04; H, 5.32; Cl, 11.00; N, 4.35. Calc. for
C29H34Cl2N2P2Ru: C, 54.07; H, 5.16; Cl, 10.84; N,
4.19%.
4.2.5. 3L5
Complex 2 (500 mg, 0.50 mmol) was treated with L5
(0.06 g, 0.55 mmol) to give 3L5. Yield 279 mg (81%) of a
light brown powder, m.p. 303 8C (dec.). 1H-NMR
(CDCl3): d (ppm) 1.75 (m, 2H, CH2), 2.67 (br, 4H,
PCH2), 4.13 (br, 4H, NH2), 6.72ꢀ
C6H3). 31P{1H}-NMR (CDCl3):
13C{1H}-NMR (CDCl3): d (ppm) 19.22 (s, CH2),
25.59 (m [26]a, Nꢃ35.02 Hz, PCH2), 127.40, 129.08,
135.57 (s, C6H4), 128.28 (m, m-C6H5), 129.48 (s, p-
C6H5), 133.10 (m, o-C6H5). FABMS; (m/z): 692.1
[Mꢁ]. Anal. Found: C, 57.48; H, 4.95; Cl, 10.24; N,
4.04. Calc. for C33H34Cl2N2P2Ru: C, 57.73; H, 4.62; Cl,
9.93; N, 3.59%.
4.2.2. 3L2
Complex 2 (500 mg, 0.50 mmol) was treated with L2
(0.048 ml, 0.55 mmol) to give 3L2. Yield 302 mg (91%)
/7.74 (m, 24H, C6H5,
d
(ppm) 43.00.
of a yellow powder, m.p. 291 8C (dec.). 1H-NMR
3
(CDCl3): d (ppm) 0.92 (d, JHH
/
ꢃ6.28 Hz, 3H, CH3),
/
1.82 (m, 2H, CH2), 2.30ꢀ2.90 (m, 10H, PCH2, NH2,
/
NCH2), 3.11 (m, 1H, NCH), 7.17ꢀ7.60 (m, 20H, C6H5).
/
31P{1H}-NMR (CDCl3): d (ppm) 41.22, 42.13 (AB
2
pattern, JPP
ꢃ
/
52.20 Hz). 13C{1H}-NMR (CDCl3): d
1
(ppm) 19.22 (s, CH2), 20.53 (s, CH3), 25.71 (d, JPC
ꢃ
/
1
4.40 Hz, PCH2), 26.10 (d, JPC
ꢃ4.40 Hz, PCH2), 49.73
/
(s, NCH2), 51.00 (s, NCH), 128.93 (m, m-C6H5), 131.21
(m, p-C6H5), 133.94 (m, o-C6H5), 137.55, 138.05 (m, i-
C6H5) FABMS; (m/z): 658.1 [Mꢁ]. Anal. Found: C,
54.97; H, 5.51; Cl, 10.77; N, 4.25. Calc. for
C30H36Cl2N2P2Ru: C, 55.26; H, 5.17; Cl, 10.91; N,
4.06%.
4.2.6. 3L6
Complex 2 (500 mg, 0.50 mmol) was treated with L6
(0.067 g, 0.55 mmol) to give 3L6. Yield 312 mg (88%) of
a brown powder, m.p. 290 8C (dec.). 1H-NMR (CDCl3):
d (ppm) 1.86 (m, 2H, CH2), 2.12 (br, 3H, CH3), 2.79 (br,
4H, PCH2), 4.25 (br, 4H, NH2), 6.5ꢀ
C6H3). 31P{1H}-NMR (CDCl3):
13C{1H}-NMR (CDCl3): d (ppm) 19.29 (s, CH2),
20.98 (s, CH3), 25.66 (m [26]a, Nꢃ35.02 Hz, PCH2),
126.27, 127.92, 128.19, 128.81, 137.49, 139.91 (s, C6H3),
128.34 (m, m-C6H5), 129.43 (m, p-C6H5), 133.09 (m, o-
C6H5). FABMS; (m/z): 706.1 [Mꢁ]. Anal. Found: C,
57.79; H, 5.14; Cl, 10.03; N, 3.96. Calc. for
/
7.8 (m, 23H, C6H5,
d
(ppm) 42.70.
4.2.3. 3L3
Complex 2 (500 mg, 0.50 mmol) was treated with L3
(0.057 ml, 0.55 mmol) to give 3L3. Yield 288 mg (85%)
of a yellow powder, m.p. 302 8C (dec.). 1H-NMR
(CDCl3): d (ppm) 1.12 (s, 6H, CH3), 1.80 (m, 2H,
/
CH2), 2.66ꢀ
/
2.91 (br, 10H, PCH2, NH2, NCH2), 7.14ꢀ
/

E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ
/
185
183
C34H36Cl2N2P2Ru: C, 57.73; H, 4.68; Cl, 9.87; N,
3.89%.
7.10ꢀ
(ppm) 42.88. 13C{1H}-NMR (CDCl3): d (ppm) 19.54 (s,
CH2), 24.79 (s, CH3), 26.48 (m [26]a, Nꢃ32.02 Hz,
PCH2), 34.45 (s, C(CH3)2), 49.97 (s, NCH2), 128.13 (m
[26]b, Nꢃ8.08 Hz, m-C6H5), 129.24 (s, p-C6H5), 133.61
(br, o-C6H5), 136.24 (m, i-C6H5). FABMS; (m/z): 681.1
[Mꢁ]. Anal. Found: C, 55.98; H, 5.87; Cl, 10.33; N,
4.08. Calc. for C32H40Cl2N2P2Ru: C, 55.98; H, 5.48; Cl,
9.35; N, 3.64%.
/
7.50 (m, 20H, C6H5). 31P{1H}-NMR (CDCl3): d
/
4.2.7. 3L7
Complex 2 (500 mg, 0.50 mmol) was treated with L7
(0.116 g, 0.55 mmol) to give 3L7. Yield 374 mg (96%) of a
yellow powder, m.p. 318 8C (dec.). 1H-NMR (CDCl3): d
(ppm) 1.87 (m, 2H, CH2), 2.76 (br, 4H, PCH2), 3.00 (d,
/
3JHH
3JHH
C6H3). 31P{1H}-NMR (CDCl3):
13C{1H}-NMR (CDCl3): d (ppm) 21.40 (s, CH2),
28.20 (m [26]a, Nꢃ35.02 Hz, PCH2), 65.69 (s, HCN),
ꢃ
/
8.80 Hz, 2H, NH), 3.50 (m, 2H, CHN) 4.24 (d,
8.8 Hz, 2H, NH), 6.64ꢀ7.73 (m, 23H, C6H5,
(ppm) 41.53.
ꢃ
/
/
d
4.2.11. 3L11
Complex 2 (500 mg, 0.5 mmol) was treated with L11
(0.066 ml, 0.55 mmol) to give 3L11. Yield 291 mg (84%)
/
125.84, 128.24, 130.54, 131.23, 131.36, 131.95, 139.34,
148.62 (C6H5). FABMS; (m/z): 796.2 [Mꢁ]. Anal.
Found: C, 61.81; H, 5.31; Cl, 8.90; N, 3.52. Calc. for
C41H42Cl2N2P2Ru: C, 61.66; H, 5.17; Cl, 8.80; N, 3.21%.
of a yellow powder, m.p. 280 8C (dec.). 1H-NMR
3
(CDCl3): d (ppm) 0.35 (t, 3H, JHH
ꢃ7.5 Hz, CH3),
/
1.07 (m, 1H, NCH), 1.27 (m, 2H, CH2CH3), 1.48 (m,
2H, PCH2CH2), 1.54 (m, 2H, CHCH2), 2.58 (s, 4H,
NH2), 2.95 (m, 6H, PCH2, NCH2), 7.10ꢀ
C6H5). 31P{1H}-NMR (CDCl3): d (ppm) 42.24, 42.53
(AB pattern, 2JPP 52.20 Hz). 13C{1H}-NMR (CDCl3):
d (ppm) 9.70 (s, CH3), 19.49 (s, PCH2CH2), 26.46 (2m,
PCH2), 33.15 (s, CH2CH3), 34.85 (s, CHCH2CH2),
40.50 (s, NCH2), 52.35 (s, NCH), 127.83, 128.32,
/
7.50 (m, 20H,
4.2.8. 3L8
Complex 2 (500 mg, 0.5 mmol) was treated with L8
(0.116 g, 0.55 mmol) to give 3L8. Yield 367 mg (94%) of
a yellow powder, m.p. 318 8C (dec.). 1H-NMR (CDCl3):
d (ppm) 1.87 (m, 2H, CH2), 2.75 (br, 4H, PCH2), 3.05
ꢃ
/
(d, 3JHH
3JHH
8.8 Hz, 2H, NH), 6.5ꢀ
C6H3). 31P{1H}-NMR (CDCl3):
13C{1H}-NMR (CDCl3): d (ppm) 19.98 (s, CH2),
26.57 (m [26]a, Nꢃ35.02 Hz, PCH2), 64.03 (s, HCN),
ꢃ
/
8.8 Hz, 2H, NH), 3.55 (m, 2H, CHN) 4.22 (d,
7.8 (m, 23H, C6H5,
(ppm) 41.54.
129.37, 133.06, 134.04 (C6H5). FABꢀMS; (m/z): 686.1
/
ꢃ
/
/
[Mꢁ]. Anal. Found: C, 55.98; H, 5.87; Cl, 10.33; N,
4.08. Calc. for C32H40Cl2N2P2Ru: C, 55.78; H, 5.76; Cl,
10.45; N, 4.07%.
d
/
129.5, 130.2, 130.5, 131.0, 131.1, 131.5, 135.3, 142.7
(C6H5). FABMS; (m/z): 796.1 [Mꢁ]. Anal. Found: C,
61.81; H, 5.31; Cl, 8.90; N, 3.52. Calc. for
C41H42Cl2N2P2Ru: C, 61.69; H, 5.10; Cl, 8.74; N,
3.76%.
4.2.12. 3L12
Complex 2 (500 mg, 0.5 mmol) was treated with L12
(0.057 ml, 0.55 mmol) to give 3L12. Yield 219 mg (65%)
of a yellow powder, m.p. 180 8C (dec.). 1H-NMR
(CDCl3): d (ppm) 0.78 (m, 4H, CH2CH2N), 1.18 (m,
4H, CH2N), 1.59 (m, 4H, CH2), 2.63, 2.74 (m, 8H,
PCH2, NH2), 7.12ꢀ
(CDCl3): d (ppm) 41.71. 13C{1H}-NMR (CDCl3): d
(ppm) 19.57 (s, CH2), 26.87 (m [26]a, Nꢃ34.02 Hz,
PCH2), 28.91 (s, CH2CH2N), 41.91 (s, NCH2), 128.24,
129.43, 132.52, 133.93 (C6H5). FABMS; (m/z): 672.1
[Mꢁ]. Anal. Found: C, 55.36; H, 5.69; Cl, 10.54; N,
4.17. Calc. for C31H38Cl2N2P2Ru: C, 55.38; H, 5.47; Cl,
10.35; N, 3.84%.
4.2.9. 3L9
/
7.68 (m, 20H, C6H5). 31P{1H}-NMR
Complex 2 (500 mg, 0.50 mmol) was treated with L9
(0.046 ml, 0.55 mmol) to give 3L9. Yield 317 mg (96%)
of a yellow powder, m.p. 288 8C (dec.). 1H-NMR
(CDCl3): d (ppm) 1.52 (br, 6H, N(CH2)3, 1.84 (m, 2H,
/
CH2), 2.74, 2.81 (br, 8H, NH2, PCH2), 7.10ꢀ7.60 (m,
/
20H, C6H5). 31P{1H}-NMR (CDCl3): d (ppm) 42.53.
13C{1H}-NMR (CDCl3): d (ppm) 19.52 (s, PCH2CH2),
26.56 (m [26]a, Nꢃ/35.02 Hz, PCH2), 29.47 (s,
NCH2CH2), 40.29 (s, NCH2), 128.06 (m [26]b, Nꢃ
/
4.3. General procedure for the catalytic studies
8.08 Hz, m-C6H5), 129.4 (s, p-C6H5), 133.6 (br, o-
C6H5), 136.4 (m, i-C6H5). FABMS; (m/z): 685.1 [Mꢁ].
Anal. Found: C, 54.71; H, 5.51; Cl, 10.77; N, 4.25. Calc.
for C30H36Cl2N2P2Ru: C, 54.78; H, 5.17; Cl, 10.51; N,
3.99%.
The respective diamine[bis(diphenylphosphino)propa-
ne]ruthenium(II) complexes 3L1ꢀ3L12, (0.012 mmol)
/
was placed in a 200 ml Schlenk tube and solid KOH
(0.12 mmol) was added as a cocatalyst. The solid
mixture was stirred and warmed during the evacuation
process to remove oxygen and water. Subsequently the
Schlenk tube was filled with argon and 20 ml of 2-
propanol. The mixture was vigorously stirred, degassed
4.2.10. 3L10
Complex 2 (500 mg, 0.5 mmol) was treated with L10
(0.065 ml, 0.55 mmol) to give 3L10. Yield 291 mg (90%)
of a yellow powder, m.p. 270 8C (dec.). 1H-NMR
(CDCl3): d (ppm) 0.75 (s, 6H, CH3), 1.79 (m, 2H,
CH2), 2.50 (br, 4H, NCH2), 2.73 (br, 8H, NH2, PCH2),
by two freezeꢀ
/
thaw cycles, and then sonicated for 20ꢀ40
/
min (this is important to complete the dissolving of the
catalyst and cocatalyst). A solution of trans-4-phenyl-3-

184
E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ185
/
Table 3
Crystal data and structure refinement parameters for 3L1, 3L2, and 3L8
3L1
3L2×CH2Cl2
3L8
Empirical formula
Formula weight
Crystal color
C29H34Cl2N2P2Ru
644.49
Yellow
C31H38Cl4N2P2Ru
743.44
Yellow
C41H42Cl2N2P2Ru
796.68
Orange
Crystal size (mm)
Crystal system, space group
0.6ꢄ0.3ꢄ0.1
0.4ꢄ0.4ꢄ0.2
0.1ꢄ0.7ꢄ0.3
Triclinic, P1
10.2172(12)
13.4835(17)
14.3403(14)
107.817(9)
93.685(11)
102.019(12)
2
¯
¯
Triclinic, P
/
1/
Triclinic, P
/
1/
˚
a (A)
9.984(4)
12.519(7)
13.476(8)
109.38(8)
105.78(5)
105.15(4)
2
10.0194(15)
12.397(2)
14.500(5)
82.51(3)
74.387(18)
68.441(15)
2
˚
b (A)
˚
c (A)
a (8)
b (8)
g (8)
Z
m (mmꢂ1
F(000)
)
0.881
660
2.27 to 27.52
0.942
760
2.25 to 27.50
0.697
820
2.06 to 27.50
u Range (8)
Limiting indices, hkl
ꢂ12 to 12; ꢂ14 to 14; ꢂ17 to 17 ꢂ12 to 12; ꢂ16 to 15; ꢂ18 to 18 ꢂ12 to 13; ꢂ16 to 16; ꢂ18 to 18
Reflections collected/unique
Absorption correction
Max and min transmission
Data/restraints/parameters
Goodness-of-fit on F2
12 434/6234 [Rintꢃ0.0352]
Empirical
14 759/7384 [Rintꢃ0.0225]
None
16 453/16 453 [Rintꢃ0.0000]
Empirical
0.9169 and 0.7419
6234/0/326
ꢀ/
0.8335 and 0.5580
16 453/3/866
7384/0/363
1.042
1.083
1.047
Final R indices [I ꢀ2s(I)], R1/wR2 0.0318/0.0755
0.0290/0.0728
0.0326/0.0747
0.0276/0.0687
0.0315/0.0706
ꢂ0.021(18)
0.0086(3)
0.533 and ꢂ0.513
R indices (all data), R1/wR2
Absolute structure parameter
Extinction coefficient
0.0366/0.0800
ꢀ/
ꢀ/
0.0057(5)
0.652 and ꢂ1.447
0.0027(4)
1.196 and ꢂ0.815
Largest difference peak and hole
ꢂ3
˚
(e A
)
˚
(lꢃ0.71073 A) was used for the measurement of
butene-2-one (12.0 mmol) in 40 ml of 2-propanol was
subjected to a freezeꢀthaw cycle in a different 200 ml
/
/
intensity data in the v-scan mode at a temperature of
173(2) K. Cell parameters were determined from 35 to
50 automatically centered reflections. The intensity data
was corrected for polarization and Lorentz effects.
Structure solution and refinement were carried out using
the Bruker SHELXTL package [27]. The structures were
solved by Patterson synthesis, followed by identification
of non-hydrogen atoms in successive Fourier maps.
Refinement was carried out with full-matrix least-
squares methods based on F2, with anisotropic thermal
parameters for all non-hydrogen atoms. Hydrogen
atoms were included at calculated positions using a
riding model with isotropic temperature factors equal to
1.2 times the Ueq value of the corresponding parent
atom.
Schlenk tube and was added to the catalyst solution.
Finally the reaction mixture was transferred to a
pressure Schlenk tube which was pressurized with
dihydrogen of 3 bar. The reaction mixture was vigor-
ously stirred at 35 8C for 1 h. During the hydrogenation
process samples were taken from the reaction mixture
after the gas was been removed to control the conversion
and turnover frequency. After this procedure the
pressure Schlenk tube was pressurized again with
hydrogen (PH
ꢃ3 bar). The samples were inserted by
/
a special glass2syringe into a gas chromatograph and the
kind of the reaction products was compared with
authentic samples.
4.4. X-ray structural analyses for complexes 3L1, 3L2,
and 3L8
5. Supplementary material
Crystallographic details of the structure determina-
tion of 3L1, 3L2, and 3L8 are summarized in Table 3.
Crystals of 3L1, 3L2, and 3L8 were obtained by slow
diffusion of diethyl ether into a dichloromethane solu-
tion of the complexes. A selected crystal was mounted
on a Siemens P4 four-circle diffractometer by using a
perfluorinated polyether (Riedel de Haen) as protecting
Crystallographic data (excluding structure factors) for
the structures in this paper have been deposited with the
Cambridge Crystallographic Data Centre as supplemen-
tary publication number CCDC 190294, 190295,
190296. These data can be obtained free of charge
from The Director, CCDC, 12 Union Road, Cambridge
agent. Graphite-monochromated Moꢀ
/
Ka radiation
CB2 1EZ, UK (Fax:
ꢁ44-1223-336033; e-mail:
/

E. Lindner et al. / Journal of Organometallic Chemistry 665 (2003) 176ꢀ
/
185
185
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1466.
Acknowledgements
[13] R. Noyori, M. Yamakawa, S. Hashiguchi, J. Org. Chem. 66
(2001) 7931.
This work was supported by the Deutsche For-
schungsgemeinschaft (Graduiertenkolleg ‘Chemie in
Interphasen’ Grant. No. 441/2-01, Bonn-Bad Godes-
berg, Germany) and the Fonds der Chemischen Indus-
trie.
[14] O. Pamies, J.E. Backvall, Chem. Eur. J.
¨ ¨
7
(2001)
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1
[26] A part of an AXX? pattern: (a) Nꢃ
/
j JPCꢁ3
/
JPCj; (b) Nꢃ
/
3
j JPCꢁ5
JPCj.
/
[27] SHELXTL NT 5.10, Bruker AXS, Madison, WI, USA, 1998.