Ruthenium(II) diphosphine(phosphine)/imine/amine/CO complexes as efficient catalysts in transfer hydrogenation of ketones

Article abstract of DOI:10.1016/j.jorganchem.2018.07.038

Treatment of [RuCl₂(CO)₂]_n with different phosphine ligands, four Ru(II) complexes of cis-, cis-, trans- RuCl₂(CO)₂L₂ (L = PH(C₆H₁₁)₂ (1), PPh₃ (2), PPh₂(C₆F₅) (3) and PMe₃ (4)), in which 1 and 3 are novel complexes, have been generated in methylene chloride and isolated as pure compound in solid. In CH₂Cl₂ mixed 1:1 molar ratio of RuCl₂(PPh₃)₃ and 1,1′-bis(diphenylphosphine)ferrocene (DPPF), and further reacted with quantitative 2-aminopyridine (ampy), 2-picolylamine (picam) and pyridine ligands, the complexes of RuCl₂(DPPF)(ampy) (5), RuCl₂(DPPF)(picam) (6) and RuCl₂(DPPF)(Py)₂ (7) were generated in situ and isolated in solid. All complexes are fully characterized by multinuclear NMR (¹H, ¹³C, ³¹P and ¹⁹F), element analysis and FTIR spectroscopies. Meanwhile, the single crystal structures of 1 and 8 complexes were determined by X-ray crystallography. The observed IR and crystal data of 1 ～ 4 clearly indicate that different phosphine donor ligands occupying trans axis position of Ru(II)Cl₂(CO)₂ skeleton can affect the coordination carbonyl C-O bond distance (1.143(3) ? (1), 1.135(3) ? (4) and 1.131(5) ? (2)), and this interaction can be quantitatively detected by its FTIR vibration frequencies. The homogeneous hydrogenation transfer catalytic reactivity of so-synthesized complexes has been tested in a basic 2-propanol solution and they indeed perform the catalytic activities in different behavior, e.g. complexes 1 and 6 are the most active catalysts and represent maximum conversion yield (1: 90.4% and 6: 90.0%) and turnover frequency (TOF) (1 18.84 h^?1 and 6 37.5 h^?1) at our tested experimental condition of these two types of structural complexes, which are discussed in the details.

Full text of DOI:10.1016/j.jorganchem.2018.07.038

Accepted Manuscript
Ruthenium(II) diphosphine(phosphine)/imine/amine/CO complexes as efficient
catalysts in transfer hydrogenation of ketones
Sai Ge, Jin Zhang, Jianguo Zhao, Imran Ulhaq, Guibin Ma, Robert McDonald
PII:
S0022-328X(18)30346-2
10.1016/j.jorganchem.2018.07.038
JOM 20525
DOI:
Reference:
To appear in: Journal of Organometallic Chemistry
Received Date: 10 May 2018
Revised Date: 13 July 2018
Accepted Date: 31 July 2018
Please cite this article as: S. Ge, J. Zhang, J. Zhao, I. Ulhaq, G. Ma, R. McDonald, Ruthenium(II)
diphosphine(phosphine)/imine/amine/CO complexes as efficient catalysts in transfer hydrogenation of
ketones, Journal of Organometallic Chemistry (2018), doi: 10.1016/j.jorganchem.2018.07.038.
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to
our customers we are providing this early version of the manuscript. The manuscript will undergo
copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please
note that during the production process errors may be discovered which could affect the content, and all
legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT
Graphical abstract

ACCEPTED MANUSCRIPT
Ruthenium(II) Diphosphine(phosphine)/Imine/Amine/CO Complexes as
Efficient Catalysts in Transfer Hydrogenation of Ketones
1
1
*1
2
*2
Sai Ge, Jin Zhang , Jianguo Zhao, Imran Ulhaq, Guibin Ma, Robert
2
McDonald
1
Institute of Carbon Materials Science, Shanxi Datong University, Datong, Shanxi
Province, 037009, PR China
2
Department of Chemistry, University of Alberta, Edmonton, Alberta,
T6G 2G2, Canada
*
Corresponding authors: E-mail address: jgzhaoshi@163.com (Prof. J. Zhao) or
guibin@ualberta.ca (Dr. G. Ma)
Abstract
Treatment of [RuCl
2
(CO)
2
]
n
with different phosphine ligands, four Ru(II) complexes
of cis-, cis-, trans- RuCl (CO) L (L = PH(C H ) (1), PPh (2), PPh (C F ) (3) and
2
2
2
6
11 2
3
2
6 5
PMe
and isolated as pure compound in solid. In CH Cl mixed 1:1 molar ratio of RuCl (PP )
3 3
3
(4)), in which 1 and 3 are novel complexes, have been generated in methyl chloride
2
2
2
and 1,1’-bis(diphenylphosphine)ferrocene (DPPF), and further reacted with quantitative
-aminopyridine (ampy), 2-picolylamine (picam) and pyridine ligands, the complexes of
RuCl (DPPF)(ampy) (5), RuCl (DPPF)(picam) (6) and RuCl (DPPF)(Py) (7) were
2
2
2
2
2
generated in situ and isolated in solid. All the complexes are fully characterized by
1
13
31
19
multinuclear NMR ( H, C, P and F), element analysis and FTIR spectroscopies.
Meanwhile, the single crystal structures of 1, 8 and 9 complexes were determined by X-
ray crystallography. The observed IR and crystal data of 1-4 clearly indicate that different
phosphine donor ligands occupying trans axis position of Ru(II)Cl (CO) skeleton can
2
2
affect the coordination carbonyl C-O bond distance (1.143 Å (1), 1.136 Å (4) and 1.131
Å (2)), and this interaction can be quantitatively detected by its FTIR vibration
frequencies. The homogeneous hydrogenation transfer catalytic reactivity of so-
synthesized complexes have been tested in a basic 2-propanol solution and they indeed
perform the catalytic activities in different behavior, which are discussed in the details.
1

ACCEPTED MANUSCRIPT
1
. Introduction
Transfer hydrogenation of ketones by ruthenium(II) catalysts is currently one of the
1
most appealing synthesis routes to generate alcohols. Ruthenium(II) complexes
containing both nitrogen and phosphino ligands are well-known since the pioneering
2
works to synthesis of [RuCl (PPh ) ] , and the synthesis of a large number of derivatives
2
3 3
3
with different combinations of P and N donor ligands. Recently, Noyori and co-workers
have developed highly active catalyst precursors of the type trans-
RuCl (diphosphine)(1,2-diamine) with both chiral P-P and H N---NH ligands for highly
2
2
2
4
stereoselective hydrogenation of ketones, and the mechanism evidence has been
provided that the Ru-H/−NH motif is a crucial component for the efficient activity of
2
4
d,4e
these catalysts.
It is well-established that these types of ruthenium complexes can also
catalyze the transfer hydrogenation of ketones by means of 2-propanol as the hydrogen
source.
Dihalodicarbonylruthenium(II) compounds were first reported by Manchot and Konig
5
6
7
in 1924. Cotton and Farthing, and later Cleare and Griffith, have reported that
refluxing RuCl ⋅xH O with formic acid produced [RuCl (CO) ] almost quantitatively.
3
2
2
2 n
So halocarbonylruthenium(II) [RuX (CO) ] has been considered to be a very useful
2
2 n
8
2b,9
precursor for the synthesis of a variety of complexes. Wilkinson
first reported
1
0
compounds of type [RuCl (CO) L ] (L = PPh or AsPh ). Later, Walter and Peter
2
2
2
3
3
2 2 2
reported [RuX (CO) L ] (L is mono- and bidentate ligands containing N, P S Se and Te
donor atoms). Thereafter, a variety of Ru(II) complexes, containing CO and various
1
1
ligands, have been synthesized due to their structural novelty and catalytic
1
2
applicability. To be an effective catalyst for these saturated coordinative complexes, it
must first dissociate a ligand in order to bind one of the substrates and gain entry into a
catalytic cycle. Krassowski and Nelson discovered that complexes of trans-
(
R P) RuCl (CO) isomerize to the thermodynamically preferred cis isomer by a
3 3 2
1
2a
dissociation of phosphine,
similarly, complex of ttt-(R P) RuCl (CO) thermally
3 2 2 2
1
3
isomerize through a dissociation of CO. The CO dissociation is considered as the
control key for the initialization of the catalytic cycles. The catalytic hydrogenation
3 2 2 2
activity of (R P) RuCl (CO) might improve by using the cocatalyst of trimethylamine
1
4
oxide, which can help remove CO as CO2. This reaction is generally limited to the
2

ACCEPTED MANUSCRIPT
-1
complexes with ν(CO) greater than 2000 cm and CO force constants greater than 16.0
-1 14c
millidynes/cm .
We have synthesized a series of Ru(II) complexes previously and studied their
hydrogenation transfer reactivity by selection of 1,1’-bis(diphenylphosphino)ferrocene
(DPPF) as a ‘constant’ bidentate P-P ligand and varied the bidentate N-N ligand using
1
5
different diamine and diimine ligands. We found that diimine has comparable catalytic
ability as diamine. We wanted more evidence in order to understand the catalytic
mechanism of systems such as mixed amine and imine ligands, as well as replacing the N
donor ligands with CO. In current work, we have synthesized a few complexes using
2
−aminopyridine (ampy) and 2−picolylamine (picam) bidentate mixed amine and imine
coordination atomic ligands. Additionally, four [RuCl (CO) (L) ] complexes with a
2
2
2
9
series of different substituted phosphine ligands L of PH(C H ) (1), PPh (2),
6
11 2
3
16
6 5 2 6 5 3 3
P(C H ) (C F ) (3) and P(CH ) (4) are synthesized and further tested for their catalytic
reactivity of hydrogen-transfer to ketones in identical condition, which generated more
evidence to fully understand the mechanism and reactivity procedure.
2
. Experimental
All experiments and manipulations were conducted under an inert atmosphere using
standard Schlenk techniques. The solvents used in preparations were rigorously dried,
and either distilled under Ar immediately prior to use, or stored with Teflon taps inside
the dry-box. CH
ruthenium precursors of [RuCl (PPh ) ] and [RuCl (CO) ]
2 n
2 2 2
Cl (CaH ); benzene, diethyl ether (sodium metal/benzophenone). The
17
6,7
were prepared exactly as
2
3 3
2
described in the literature.
NMR solvents in solution were dried with 4
recorded at room temperature (~20°C) on a Bruker AV 400 instrument (400.0 MHz for
Å
molecular sieves. NMR spectra were
1
31
1
13
1
H, 162.0 MHz for P{ H}, and 100.6 MHz for C{ H} NMR); CD Cl , CD Cl and
2
2
3
DMSO-d solutions of the complexes were used. Residual protonated species in the
6
1
13
deuterated solvents were used as internal references; all H and C shifts are reported in
ppm (s = singlet, d = doublet, t = triplet, m = multiplet), relative to external TMS, while
3
1
1
P{ H} NMR shifts are reported relative to external 85% aqueous H PO ; J values are
3
4
given in Hz. IR spectra data were recorded using a Nic-Plan FTIR Microscope. Elemental
3

ACCEPTED MANUSCRIPT
analyses were performed on a The Carlo Erba EA 1108 elemental analyzer. Gas
Chromatography (GC) analyses were performed using an HP Hewlett Packard 5890 GC,
fitted with an HP-5 column (50 m x 0.32 mm x 0.52 µm phase thickness), the oven
temperature ranged from 50-280°C (10°C/min) with an injection and detector
temperature of 220°C. IR, GC and EA were carried out in The Analytical and
Instrumentation Laboratory, Chemistry Department, University of Alberta.
2
.1. Synthesis of cis-, cis- trans-[RuCl
2 2 6 11 2 2
(CO) (PH(C H ) ) ] (1)
A typical procedure involved the following. The complex [RuCl (CO) ] (23.0 mg;
2
2 n
0
.1 mmol) were loaded in a round-bottom tube under N and dissolved in 10 ml CH Cl ,
2 2 2
6 11 2
and a slight excess of the ligand dicyclohexylphosphine PH(C H ) (44.0 mg; 0.22 mmol)
were added. The mixture was stirred under nitrogen for 2 hours. The solvent was
removed under reduced pressure. The remaining residue was stirred in diethyl ether (10
ml) for approximately 10 minutes and then filtered. The pure light yellow to white solid
was dried under vacuum for 2 hours. Data for complex 1: Yield 80%. Anal. Calc. for
1
C
26
H
46
O
2
P
2
Cl
2
Ru: C, 50.0; H, 7.37. Found: C, 49.84; H, 7.37. H NMR (399.79 MH,
1
3
1
CD Cl , 22ºC): 2.52 (m, 1H, PCH), 1.26 ~ 2.02 (m, 12H, -CH - ring). C{ H} (100.58
2
2
2
2
1
MHz, CD
2 2
Cl , 22ºC): 194.90 (t, JP-C = 10.7 Hz, CO), 33.35 (t, JP-C = 12.21 Hz),
2
2
13
1
3
2.43(s), 30.72(s), 27.47 (d, J = 5.73 Hz), 27.37 (d, J = 5.73 Hz), 26.06(s). C{ H,
P-C
P-C
3
1
P} (100.58 MHz, CD Cl , 22ºC): 194.90 (s) (CO), 33.35(s), 32.43(s), 30.72(s), 27.41(s),
2
2
3
1
1
2
2 2 2
7.37(s), 26.06(s); P{ H} (162.0 MHz, CD Cl , 22ºC): 37.21. IR: 2928s, 2848s (-CH
C-H stretching), 2349s (-PH P-H stretching), 2035vs, 1974vs (C≡O stretching), 1626s,
1
8
444vs, 1342s, 1303s, 1271s, 1205s, 1184s, 1174s, 1116s, 1073s, 1043m, 1005s, 915s,
98m, 859s, 837s, 829s, 817s, 722s. The abbreviations are: vs, very strong; s, strong; m,
medium. The white crystal suitable for X-ray structural determination was obtained from
the CH Cl solution by very slow evaporation of the solvent.
2
2
2
.2. Synthesis of cis-, cis- trans-[RuCl (CO) (PPh ) ] (2)
2 2 3 2
2 2 n 3
The complex [RuCl (CO) ] (23.0 mg; 0.1 mmol) and triphenylphosphine PPh (78.6
mg; 0.3 mmol) were loaded in a round-bottom tube under N and dissolved in 10 ml
2
CH
2
Cl
2
. The mixture was stirred for 2 hours. The solvent was removed under reduced
4

ACCEPTED MANUSCRIPT
pressure and the white powder was obtained and washed twice with diethyl ether (each
time with 5 ml), and dried under vacuum. Data for complex 2: Yield 81.0%. Anal. Calc.
1
for C H O P Cl Ru: C, 60.59; H, 4.02. Found: C, 60.53; H, 4.12. H NMR (399.79
3
8
30
2
2
2
2 2
MHz, CD Cl , 22ºC): 7.41 (m), 7.43 (m), 7.45 (m), 7.47 (m) (10H); 7.90 (m), 7.91 (m),
1
3
1
2
7
.93 (m), 7.94 (m) (5H). C{ H} (100.58 MHz, CD Cl , 22ºC): 193.01 (t, J = 10.5
2
2
P-C
2
1
4
Hz, CO), 134.72 (t, JP-C = 5.3 Hz), 132.12 (t, JP-C = 23.9 Hz), 131.10(s), 128.61 (t, JP-C
1
3
1
31
=
5.2 Hz). C{ H, P} (100.58 MHz, CD Cl , 22ºC): 193.02(s) (CO), 134.72(s),
2 2
3
1
1
1
2
1
7
32.12(s), 131.10(s), 128.61(s); P{ H} (162.0 MHz, CD Cl , 22ºC): 19.91. IR: 3057m,
2 2
973m, 2862m (Ph C-H stretching), 2055vs, 1991vs (C≡O stretching), 1586m, 1572s,
482s, 1433vs, 1316m, 1286m, 1268m, 1190s, 1159s, 1088vs, 1028s, 998s, 935m, 758m,
46s, 689vs. The abbreviations are: vs, very strong; s, strong; m, medium.
2
.3 Synthesis of cis-, cis- trans-[RuCl
2 2 2 6 5 2
(CO) (PPh (C F )) ] (3)
The complex [RuCl (CO) ] (23.0 mg; 0.1 mmol) and diphenyl(pentafluorophenyl)
2
2 n
2 6 5 2
phosphine PPh C F (70.0 mg; 0.2 mmol) were loaded in a round-bottom tube under N
and dissolved in 10 ml CH Cl . The mixture was stirred for 2 hours. The solvent was
2
2
removed under reduced pressure and the white powder was obtained and washed twice
with hexane (each time with 5 ml), and dried under vacuum. Data for complex 3: Yield
1
8
0.43% (75.0 mg). H NMR (399.79 MH, CD Cl , 22ºC): 7.52 ∼ 7.44 ppm (m, Ph group).
2
2
1
3
1
2
1
C{ H} (100.58 MHz, CD Cl , 22ºC): 192.05 (t, J = 10.8 Hz, CO), 134.23 (t, J
P-C
=
=
2
2
P-C
3
1
6
.1 Hz), 131.90 (s), 129.61(s), 128.91 (t, JP-C = 5.4 Hz) (Ph group); 147.18 (dm, JC-F
1
1
2
53.46 Hz.), 143.74 (dm, J = 258.2 Hz.), 138.67 (dm, J = 252.2 Hz.), 107.60 (t,
C-F C-F
2
13
1
31
JC-F = 18.8 Hz.) (-C F group). C{ H, P} (100.58 MHz, CD Cl , 22ºC): 192.06(s,
6
5
2
2
CO), 134.24(s), 131.90(s), 129.60(s), 128.91(s) (Ph group), 147.18 (double multiple (dm),
1
1
1
2
JF-C = 256 Hz), 143.73(dm, J = 258 Hz), 138.66(dm, J = 252 Hz), 107.61(t, J
F-C
F-C
F-C
1
3
19
31
=
16.7 Hz); C{ F, P} (100.58 MHz, CD
2
2
Cl , 22ºC): 192.06(s, CO), 134.20(double
1
1
1
triplet (dt), J
= 162.4 Hz.), 131.80(dt, J
= 161.4 Hz.), 131.80(dt, J
= 161.4
H-C
H-C
H-C
1
1
Hz.), 129.69(t, J
= 6.4 Hz.), 128.11(d, J
= 7.4 Hz.) (Ph group), 147.20(s),
H-C
H-C
3
1
1
1
1
1
43.74(s), 138.66(s), 107.61(s) (-C F group). P{ H} (162.0 MHz, CD Cl , 22ºC):
6
5
2
2
1
9
3.82. F (376.3 MHz, CD Cl , 22ºC): -121.79 (d, 2F), -148.02 (triple triplet (tt), 1F), -
2
2
59.61 (tt, 2F). IR: 3060m, 2957m, 2927m, 2860m (Ph, C-H stretching), 2062vs, 2002vs
(C≡O stretching), 1642s, 1589m, 1575m, 1520vs, 1475vs, 1437s, 1388s, 1294s, 1194s,
5

ACCEPTED MANUSCRIPT
1
093vs, 1027m, 999m, 981vs, 842m, 742s, 691s. The abbreviations are: vs, very strong; s,
strong; m, medium.
.4 Synthesis of cis-, cis- trans-[RuCl (CO) (P(CH ) ) ] (4)
2
2
2
3 3 2
2 2 n
The compound was synthesized with the reaction between [RuCl (CO) ] and
trimethylphosphine (P(CH ) ), and the crystal structure determination showed it was the
3
3
cis-, cis- trans-[RuCl
2
(CO)
2
3 3 2
(P(CH ) ) ] (4), exactly identical to the structure published in
literature which was prepared by passing CO gas through a mixture of RuCl and P(CH )
3
3 3
1
6
in 2-methoxyethanol.
.5 trans-RuCl (DPPF)(ampy) (5).
DPPF (55 mg, 0.1 mmol) was added to a rapidly stirred, 10 mL CH Cl suspension of
2
2
2
2
2 3 3
RuCl (PPh ) (96 mg, 0.1 mmol). The color change from purple-black to red was
observed within a few minutes. The solution was stirred for 30 min, when a CH Cl2
2
solution of 2-aminopyridine (9.4 mg, 0.1 mmol) was added, giving an immediate color
change to yellow-green. After a further 30 min, the solvent was removed in vacuo and 5
ml of diethyl ether (Et O) were added. The yellow product was filtered off, washed twice
2
with ether (2 x 5 ml), and then dried under vacuum. Yield: 73 mg (93%). Anal. Calcd for
1
C H Cl N P FeRu: C, 57.07; H, 4.15; N, 3.41. Found: C, 56.73; H, 4.16; N, 3.42. H
39
34
2
2 2
NMR (DMSO-d ): 4.32 (s, br. 8H, C H ), 4.55 (s, br. 2H, -NH , Py), 6.44 (m, 1H, CH,
6
5
4
2
1
3
1
Py), 7.20-7.34 (m, 20H, Ph), 7.38 (m, 1H, CH, Py), 7.87 (m, 1H, CH, Py). C{ H} NMR
(
DMSO-d ): 72.1 (s, C H ), 75.0 (s, C H ), 79.1 (s, C H ), 107.9 (s, Py), 111.7 (s, Py),
6
5
4
5
4
5
4
2
1
1
1
26.2 (d, JCP = 5.0, Ph), 128.7 (d, JCP = 6.5, Ph), 133.2 (d, JCP = 19.0, Ph), 135.8 (d,
1
13
1
31
JCP = 98.0, Ph), 136.8 (s, Py), 147.6 (s, Py),. 159.7 (s, Py). C{ H, P} NMR (DMSO-
1
3
1
31
1
d ): the above C{ H }signals became singlets. P{ H} NMR (DMSO-d ): 32.34 (br, s).
6
6
-1
IR (cm ): 3298, 3188, 3102, 3057 (νN-H and νC-H); 1875, 1602, 1533, 1478, 1433 (νC=C
,
and C-H, N-H bending), 1154, 1095, 1032, 747, 697 (νC-C, νC-N, νC-P and bending).
2
.6 trans-RuCl (DPPF)(picam) (6).
2
Complexes 6 were synthesized using the same procedure and solvents as described
for the synthesis of 5. Yield: 81 mg (97%). Anal. Calcd for C H Cl N P FeRu: C, 57.42;
4
0
36
2
2 2
1
H, 4.31; N, 3.35. Found: C, 57.73; H, 4.35; N, 3.36. H NMR (CD Cl ): 2.12 (s, 2H,
2
2
2 2 5 4 5 4 5 4
CH ), 4.12 (s, 2H, NH ), 4.23 (s, 2H, C H ), 4.30 (s, 2H, C H ), 4.40 (s, 2H, C H ), 4.82
1
3
1
(
s, 2H, C H ), 7.17-8.19 (m, 20H, Ph), 6.67-8.61 (m, 4H, Py). C{ H}: 50.5 (s, CH ),
5
4
2
6

ACCEPTED MANUSCRIPT
3
3
6
9.3 (d, CH of C
5
H
4
, JPC=5.15 Hz), 72.1 (d, CH of C
5
H
4
, JPC=5.91 Hz), 75.9 (d, CH of
2
2
1
C H , J =7.06 Hz), 78.0 (d, CH of C H , J =7.44 Hz), 82.5 (d, C of C H , J =46.92
5
4
PC
5
4
PC
5
4
PC
Hz), 120.9 (s, CH of Py), 122.4 (s, CH of Py), 127.6 (q, CH of Ph), 129.6 (t, CH of Ph),
34.7 (d, CH of Ph), 135.9 (d, CH of Ph), 139.0 (d, C of Ph), 156.4 (d, CH of Py), 163.9
1
1
3
1
31
(
d, CH of Py). C{ H, P}: 50.5 (s, CH ), 69.3 (s, CH of C H ), 72.1 (s, CH of C H ),
2 5 4 5 4
7
1
5.9 (s, CH of C
5 4 5 4 5 4
H ), 78.0 (s, CH of C H ), 82.5 (s, C of C H ), 120.9 (s, CH of Py),
22.4 (s, CH of Py), 127.6 (s, CH of Ph), 129.6 (s, CH of Ph), 134.7 (s, CH of Ph), 135.9
3
1
1
(
s, CH of Ph), 139.0 (s, C of Ph), 156.4 (s, CH of Py), 163.9 (s, CH of Py). P{ H} NMR:
2
2
- +
-1
5
3
2.1 (d, JPP = 38.3), 41.5 (d, JPP = 38.3). ESI-MS (THF): m/z 798 [M-Cl ] . IR (cm ):
332, 3225, 3055, 2915 (νN-H and νC-H), 1573, 1481, 1435, 1302 (νC=C, and C-H, N-H
bending), 1154, 1120, 1090, 1032, 812, 755, 747, 697 (νC-C, νC-N, νC-P and bending).
.7 trans-RuCl (DPPF)(Py) (7).
2
2
2
Complexes 7 were synthesized using the same procedure and solvents as described
for the synthesis of 5. Yield: 81 mg (92%). Anal. Calcd for C H Cl N P FeRu: C, 59.80;
4
4
38
2
2
3
2
1
H, 4.30; N, 3.16. Found: C, 60.00; H, 4.49; N, 3.06. H NMR (CD
Cl): 4.27 (s, 4H,
1
3
1
C H ), 4.76 (s, 4H, C H ), 7.20-8.81 (m, 10H, Py), 6.90-7.68 (m, 20H, Ph). C{ H}: 69.9
5
4
5
4
(
t, CH of C H ), 77.2 (t, CH of C H ), 87.3 (t, CH of C H ), 122.5 (s, CH of Py), 126.5 (t,
5 4 5 4 5 4
CH of Ph), 128.3 (s, CH of Ph), 134.7 (s, CH of Ph), 135.1 (t, CH of Py), 139.0 (t, CH of
1
3
1
31
Ph), 154.2 (s, CH of Py). C{ H, P}: 69.9 (s, CH of C H ), 77.3 (s, CH of C H ), 87.3
5
4
5
4
(s, CH of C
5 4
H ), 122.5 (s, CH of Py), 126.5 (s, CH of Ph), 128.3 (s, CH of Ph), 134.7 (s,
3
1
1
CH of Ph), 135.1 (s, CH of Py), 139.0 (s, CH of Ph), 154.2 (s, CH of Py). P{ H} NMR:
-
1
4
1
6.25 (s). IR (cm ): 3105, 3052(νC-H), 1483, 1444, 1432 (νC=C, and C-H, N-H bending),
217, 1086, 1038, 1020, 811, 745, 696 (νC-C, νC-N, νC-P and bending).
2
.8 cis-RuCl
2
(DPPF)(Phen) (8)
The synthesis and characterization of complex 8 has been published in our previous
1
5
work. The synthesis procedure and characterization detail is presented in that paper.
However, the crystal structure was not included at that time. The square needle red
crystals were grown from the CH Cl solution by very slow evaporation of the solvent.
2
2
2
.9 trans-RuCl
This compound has been synthesized previously. However, no single crystal
structure was reported in previous literature. Herein single crystals were grown in CH Cl
2 3 2
(PPh ) (Picam) (9)
3
i
2
2
7

ACCEPTED MANUSCRIPT
by slow evaporation of the solvent, and the structure was determined by X-ray diffraction.
2
.10 Crystal Structure Determination
Suitable crystals were mounted on glass fibers by means of mineral oil, and the data
were collected using graphite-monochromated MoKα radiation







Å


Data collections were performed on a Bruker PLATFORM/ SMART 1000 CCD
diffractometer. The structures were solved by direct methods using the Patterson
1
8
search/structure expansion (DIRDIF-99), and were refined using full-matrix least-
2
19
squares on F (SHELXL-93). All the non-hydrogen atoms in the structures 1, 8 and 9
were refined with anisotropic displacement parameters. The selected crystal data and
structural refinement details for 1, 8 and 9 are listed in Table 1.
3
. Results and Discussion
3
.1 Synthesis of complexes.
Reaction of polymeric [RuCl (CO) ] with two molar equiv (Ru:L = 1:2) of the
2
2 n
2 2 2 2 2
ligands, four cis, cis, trans-[RuCl (CO) (L) ] Ru(II) complexes formed in CH Cl and
isolated in white solid (L = PH(C H ) (1), PPh (2), PPh (C F ) (3) and P(CH ) ) (4))
6
11 2
3
2
6
5
3 3
(see Scheme 1). To the best of our knowledge, complexes 1 and 3 are novel preparation
9
,10,11c,16
while 2 and 4 were reported in literature,
but herein we updated the preparation
for 2 and 4 by using precursor of [RuCl (CO) ] instead of CO gas. Complexes 5−7, of
2
2 n
formulation RuCl (DPPF)(N-N) [N-N = ampy (5), picam (6), and RuCl (DPPF)(Py) ] (7)
2
2
2
(see Scheme 2), were synthesized from complex of RuCl
2
(PPh
3
)
3
via consecutive
substitution reactions. Addition of one equiv of DPPF to a CH Cl solution of
2
2
RuCl
purple to red, subsequent addition of one equiv of 2−aminopyridine (ampy),
−picolylamine (picam) or pyridine resulted in further color changes, and straightforward
2 3 3
(PPh ) under aerobic conditions resulted in a rapid color change from blackish-
2
work-up of the solutions gave good to high yields of high-purity yellow products of
complexes 5, 6 and 7 respectively. In addition, two known but unsolved crystal structures
1
5
3i
complexes of cis−RuCl (DPPF)(Phen) (8) and trans−RuCl (PPh ) (Picam) (9) have
2
2
3 2
been synthesized using the procedure developed by us and others in literature.
.2 Spectroscopic characterization
3
8

ACCEPTED MANUSCRIPT
3
1
1
The P{ H} NMR of complexes 1−4 were all singlet and this indicated that the two
3
1
1
trans-phosphine ligands were identical in each structure. P{ H} NMR signal of
complex cis, cis, trans-[RuCl (CO) (PH(C H ) ) ] (1) was monitored in CH Cl at
2
2
6
11 2 2
2
2
different molar ratio of n = Ru/PH(C H ) (1 ∼ 5). The dominant peak observed of the
6
11 2
2 2 6 11 2 2
solution was complex [RuCl (CO) {PH(C H ) } ] (1) at n = 2, and its intensity was
constant and the peak of free ligand (-23.7 ppm) increased the intensity along with
addition of more of PH(C H ) up to n = 5. It convinced us to believe that the
6
11 2
coordinated chloride and carbonyl groups were extremely stable inside the formed
species and excess addition of phosphine ligand could not substitute to them.
The solubility of complex RuCl
2
(DPPF)( ampy) (5) is incredibly low in either CDCl
3
31
1
or CD Cl , its P{ H} NMR spectrum in DMSO-d shows a very broad peak at 32.3 ppm
2
2
6
indicating existence of the rapid exchange process between ligand and solvent in DMSO
3
1
1
solution. As expected, P{ H} of complex RuCl
2
(DPPF)(picam) (6) shows a typical AX
2
double of doublets pattern at 52.1 and 41.5 ppm with J value of 38.3 Hz, which is in
pp
agreement with the bonding of unsymmetrical bidentate N−NH ligand (2-picolyamine),
2
and it causes the two coordinated P atoms in no identical or different coordinated
3
1
1
environment. The P{ H} of complex RuCl (DPPF)(Py) ] (7) gives to a singlet at 46.3
2
2
ppm, which is consistent with its formation of symmetrical molecular geometry as
expected.
The IR spectra (as shown in Table 2) of the complexes showed two equally intense
-1
ν(C≡O) bands in the range 1974 - 2062 cm attributing cis-disposition of the two
terminal carbonyl groups. The position of the ν(C≡O) bands for these four cis-, cis-,
trans- Ru(II) complexes lie in the sequence of PPh
PH(C H ) (1). Comparing to ν(C≡O) stretching bands of the polymeric [RuCl (CO) ]
2 n
2 6 5 3 3 3
(C F ) (3) > PPh (2) > P(CH ) (4) >
6
11 2
2
precursor, the ν bands of all complexes shifted to the low frequency (Table 2). The
interaction on the ν(C≡O) bands arising from the different coordinated trans-phosphine
ligands was clearly shown in the IR spectra. The phosphine ligand donor electron ability
2 6 5 3 3 3
to Ru(II) metal d orbit may increase in this sequence PPh (C F ) (3) < PPh (2) < P(CH )
(
4) < PH(C
6
H
11
)
2
(1). So, the electron density increases on the central Ru metal which
*
leads to donate more d
π
electrons to the antibonding π orbits of the CO and consequently
9

ACCEPTED MANUSCRIPT
reduces the C-O bond order, which in turn reduces or lowers the ν(CO) frequency. The
C-O bond distances were confirmed by the crystal structures. Therefore, the ν(C≡O)
II
wavelength values of cis-, cis-, trans- Ru Cl
2
(CO)
2
(L)
2
(1 - 4) (L = PH(C
6
H
11
)
2
(1), PPh
3
(
2), PPh (C F ) (3) and P(CH ) ) (4)) complexes are considered possible as probe to
2 6 5 3 3
3
evaluate the ligands (or L (R P) coordination atoms) donor electron ability, and to
determine their donation order of any different P ligands based on ν(C≡O) wavelength.
This phenomenon has been observed in a similar complex cis-, cis, trans-
1
1a
RuCl
2
(CO)
2
(Ph
3
PX)
2
, where X = O, S, Se respectively (as listed in Table 2). The
PO > Ph PS > Ph PSe. S and
vibration band positions of the ν(CO) lie in the sequence Ph
3
3
3
Se is more soft than O, so the strong soft-soft interaction between Ru(II) and S or Se,
which increases the central metal electron density and donates more electrons to the
*
11a
antibonding π orbital of the CO, and consequently weakens the CO bond order.
The ν(N-H) vibration bands of complexes 5 and 6 in solid phase were observed at
-1
-1
3
298, 3188 cm or 3332, 3225 cm respectively (as shown in Table 2), indicating
+
presence of –NH . However, complex 6 exhibited the [M-Cl] mass peak, similar to
2
1
5
2 2
RuCl (DPPF)(bipy) and RuCl (DPPF)(phen) , whereas 5 and 7 showed no molecule
mass peaks, and the dissociated pyridine and 2-aminopyridine ligands mass peaks were
observed respectively, indicating the dissociation of the weakly bonding ligands in the
gas phase.
3
.3 Crystal structures of cis
8) and trans [RuCl (PPh ) (Picam)] (9).
The crystal structures of 2 and 4 are available in the literature.
complexes 2 and 4 also grew successfully and the structural determination proved they
−[RuCl (CO) {PH(C H ) } ] (1), cis−[RuCl (DPPF)(Phen)]
2 2 6 11 2 2 2
(
−
2
3 2
1
6,20
Two crystals of
20
are the identical structures to cis-, cis-, trans-RuCl (CO) (PPh ) and cis-, cis-, trans-
2
2
3 2
1
6
RuCl (CO) (P(CH ) )
in the literature. The crystals of 1 were obtained from the
2
2
3 3 2
CH Cl solution and crystal structure has been determined and shown in Figure 1. The
2
2
selected bond lengths and bond angles are given in Table 3. In the molecular structure,
the ruthenium atom has a slightly distorted octahedral coordination with two phosphine
ligands occupying the two trans-octahedral sites, two cis CO and two cis chlorides. The
angle of P1-Ru-P2 is 177.54° and they are very close to linear, and four atoms of H1, P1,
P2 and H2 are almost located inside one plane. The torsion angle is 176.0°, which is a
1
0

ACCEPTED MANUSCRIPT
slight deviation of 4° to 180°. The average Ru-Cl bond lengths are very close in these
three structures (1, 2.429 Å; 2, 2.439 Å; 4, 2.436 Å), while the average Ru-P bond length
in 2 (2.425 Å) is slightly longer than in 1 (2.403 Å) and 4 (2.380 Å). Meanwhile the
average distances of Ru-C are 1.877 Å (1), 1.856 Å (4), and 1.860 Å (2). The average C-
1
6
20
O bond lengths of coordination CO ligands are 1.143, 1.136 and 1.131 Å in 1, 4 and 2
respectively, which display the CO bond order (or bond energy) is in the sequence of 2 >
4
> 1. These data are well in agreement with the observed IR data of the corresponding
compounds (Table 2), the longest C-O bond distance of 1 having the lowest vibration
frequency, whereas the shortest C-O distance of 2 having the highest frequency. It clearly
indicates the different phosphine ligands occupying the trans axis position of Ru(II) do
change the coordination carbonyl C-O bond distances and IR vibration frequency.
1
5
Similarly to the previously determined structure of cis-RuCl (DPPF)(bipy), the
2
crystal structure of 8 (Figure 2) revealed cis-dichloride ligands, with one chlorine
necessarily being trans to a P-atom and one trans to a N-atom; the Ru-Cl bond length for
the chlorine trans to phosphorus (2.4567 Å) is about 0.0384 Å longer than for that trans to
2
1
nitrogen, in line with the expected trans-effect (see Table 4). Comparing to the previous
1
5
similar structure, the trans-effect in 8 is slightly weaker because the two Ru-Cl bond
length difference (0.0384 Å) is less than the previous one (0.055 Å). More generally,
differences in the Ru-Cl bond of the cis-dichloro complexes are in the 0.05−0.09 Å
2
2-25
22-25
range.
Such RuCl (P-P)(N-N) structures have been discussed extensively,
and, at
2
least in one set of complexes, the trans- and cis-species have been shown to be the kinetic
2
3
and thermodynamic products, respectively.
The two planar, cyclopentadienyl rings of ferrocene within structure 8 are eclipsed
and are essentially co-planar, the average torsion angle (H-C---C-H) between the C-H of
one ring and the most adjacent one of the other ring being 36.54°; the corresponding P-C-
C-P torsion angle is 35.46°, which has more twist than the previous similar crystal
1
5
1
structure. In the solution H NMR spectrum of complex 8, there is more splitting of the
1
15
ferrocene- H signals, consistent with the greater twist evident in the solid state.
3
i
The preparation of complex 9 was reported in the literature , but without any crystal
structure data. The geometry at the Ru metal of complex 9 is a octahedral environment
(Figure 3) with a trans arrangement of the two chloride ligands. The bond lengths of Ru-
1
1

ACCEPTED MANUSCRIPT
N1 and Ru-N2 (bonding length difference 0.0068 Å) are more or less equivalent and
which is ture to Ru-Cl1 and Ru-Cl2 bond lengths (length difference 0.0068 Å), whereas
the Ru-P1 bond trans to the imine-N displays a slightly longer distance (0.0156 Å) as Ru-
P2 trans to the amine-N. The angle N1-Ru-N2 for picam is 76.26(8)°, whereas the angle
Cl1-Ru-Cl2 and Cl1-Ru-N1 are 164.89(2)° and 80.64° (Table 5), leading to a rather
1
5
distorted octahedral geometry than the structures with symmetric diamine ligands.
3
.4 Catalytic hydrogenation transfer of ketone.
3 2 2 2 3 3 3
A series of Ru(II) complexes of the types (R P) RuCl (CO) (R P = Bzl P, Ph P,
Ph MeP, PhMe P and Me P) has been used as homogeneous catalysts for hydrogenation
2
2
3
of 1-hexene (C=C bond) at 100°C under a hydrogen pressure of 100 psi in 50%
1
2a
ethanol/benzene. Herein, the activity of catalytic transfer hydrogenation of ketones
C=O bond) for the synthesized precatalysts has been tested in a basic isopropanol at
0°C under inert nitrogen atmosphere (Scheme 3). All the tested complexes perform the
homogeneous catalytic hydrogenation transfer reactivity well at the given condition
Table 6). Very interesting results have been obtained that the conversion corresponds
(
8
(
reversely to the CO vibration frequencies. Seemingly the strong bonded CO is
disadvantageous to the catalytic activity. The carbonyl complexes presented a poor
2
6
catalytic hydrogenation activity was observed in the previous literature. This
demonstrates that CO coordinated to Ru(II) is not beneficial to its hydrogenation
reactivity. As discussed in the introduction, the catalytic hydrogenation activity of
(
R P) RuCl (CO) was improved by using the cocatalyst of trimethylamine oxide, which
3 2 2 2
1
4
can help remove CO as CO . To the best of our knowledge, it is the first time that
2
activities of complexes 1-3 as a hydrogen-transfer catalyst has been tested. These tested
results provide experimental evidence to demonstrate the CO affection as hydrogen
transfer catalyst.
In the same conditions, the hydrogenation transfer of acetophenone in a basic 2-
propanol for complexes 5-7 were tested (Scheme 3, Table 6). The data indicate that
complex 6 is an efficient hydrogen-transfer catalyst, whereas 5 and 7 seem not so
efficiency. The catalytic ability of 6 is compatible with the previously synthesized trans-
1
5
RuCl (DPPF)(N-N) compounds (where N-N = ethylenediamine (En), diamine or
2
diimine). To our suprise, the monodentate imine ligand Py in 7 demonstrated less activity
1
2

ACCEPTED MANUSCRIPT
1
5
compared to the bidentate diimine bipy or phen , and even worse in 5 with 2-
aminopyridine ligand (Table 6). Regarding these types of catalysts, the proposed general
‘metal-ligand bifunctional catalysis’ mechanism for reduction of ketones implied no
direct bonding of the substrate at the Ru atomic center, but instead an outer-sphere, H-
2
7
bonding interaction between an ‘RuH-NH’ unit and the ketone. Perhaps because the
monodentate ligand Py bonding to Ru(II) is not so stable compared to the bidentate
ligands, and it is easily dissociated in solution, consequently losing the chance of
formation with the activation ‘RuH-NH’ unit. The four-member ring of Ru-bonding
ampy in 5 is incredibly unstable in solution and indeed showed very weak catalytic
activity. These are consistent with the observed mass spectroscopic results. The same
3
i
results are reported in the literature, such as bidentate P-P coordinated catalyst of cis-
-1
RuCl (Ph P(CH ) PPh )(Picam) (TOF(h ) = 300000) is much more active than the
2
2
2 4
2
-1
monodentate P catalyst of cis-RuCl (PPh ) (Picam) (TOF(h ) = 5200).
2
3 2
4
. Conclusions
A series of carbonyl substituted complexes with cis-, cis-, trans−configuration of
RuCl (CO) (R P) (1 - 4) and the complexes 5 - 7 containing mixed imine and amine
2
2
3
2
ligands have been synthesized and characterized. Hydrogenation transfer catalytic tests
demonstrated that the CO substituted precatalysts are not as efficient as the nitrogen
donor ligands. The strong bonding ability of phosphine and nitrogen ligands to Ru(II),
and their guaranteed formation of the stabilized ‘Ru-N’ unit in situ are critically
important as efficient hydrogenation transfer catalysts.
Acknowledgement
The authors thank the Natural Sciences and Engineering Research Council (NSERC) of
Canada for financial support in the form of a Discovery Grant. We also thank
Shanxi’1331 Project’ Foundation for the Construction of Collaborative Innovation Center
of Graphene Industrial Application.
Supplementary Data
Cif file for complexes 1, 8 and 9 (anisotropic thermal parameters, complete lists of bond
1
3

ACCEPTED MANUSCRIPT
lengths and angles, torsion angles, and measured and calculated structure factor
amplitudes for the structures)
.
References
[1] (a) G. Zassinovich, G. Mestroni, S. Gladiali, Chem. Rev. 92(1992) 1051-1069. (b) R.
Noyori, S. Hashiguchi, Acc. Chem. Res. 30(1997) 97-102. (c) K. Everaere, A.
Mortreux, J. F. Carpentier, Adv. Synth. Catal. 345(2003) 67-77.
[
2] (a) S. J. La Placa, J. A. Ibers, Inorg. Chem. 4(1965) 778-783. (b) T. A. Stephensons,
G. Wilkinson, J. Inorg. Nucl. Chem. 28(1966) 945-956.
[
3] (a) A. Togni, L. M. Venanzi, Angew. Chem., Int. Ed. Engl. 33(1994) 497-526. (b) F.
Fache, E. Schulz, M. L. Tommasino, M. Lemaire, Chem. Rev. 100(2000) 2159-2232.
(c) G. Chelucci, R. P. Thummel, Chem. Rev. 102(2002) 3129-3170. (d) W. Tang, X.
Zhang, Chem. Rev. 103(2003) 3029-3070. (e) K. V. L. Crépy, T. Imamoto, Adv.
Synth. Catal. 345(2003) 79-101. (f) J. K. Whitesell, Chem. Rev. 89(1989) 1581-1590.
(
g) J. M. Brown. P. A. Chaloner, In Homogeneous Catalysis with Metal Phosphine
Complexes; L. H. Pingolet, Ed.; Plenum: New York, 1983. (h) W. S. Knowles, Acc.
Chem. Res. 16(1983) 106-112. (i) W. Baratta, E. Herdtweck, K. Siega, M. Toniutti, P.
Rigo, Organometallics, 24(2005) 1660-1669. (j) V. Cadierno, P. Crochet, J. Diez, S. E.
Garcia-Garrido, J. Gimeno, Organometallics, 23(2004) 4836-4845.
[4] (a) T. Ohkuma, M. Koizumi, H. Doucet, T. Pham, M. Kozawa, K. Murata, E.
Katayama, T. Yokozawa, T. Ikariya, R. Noyori, J. Am. Chem. Soc. 120(1998) 13529-
1
3530. (b) K. Mikami, T. Korenaga, M. Terada, T. Ohkuma, T. Pham, R. Noyori,
Angew. Chem. Int. Ed. 38 (1999) 495-497. (c) M. Yamakawa, H. Ito, R. Noyori, J.
Am. Chem. Soc. 122 (2000) 1466-1478. (d) K. Abdur-Rashid, S. E. Clapham, A.
Hadzovic, J. N. Harvey, A. J. Lough, R. H. Morris, J. Am. Chem. Soc. 124 (2002)
1
5104-15118.
[5] W. Manchot, J. Konig, Ber. Dtsch. Chem. Ges. 57(1924) 2131.
[6] R. Cotton, R. H. Farting, Aust. J. Chem. 20(1967) 1283-1286.
[7] M. J. Cleare, W. P. Griffith, J. Chem. Soc. A (1969) 372-380.
[8] A. R. Joseph, Chem. Rev. 85(1985) 1-39 (and references therein).
1
4

ACCEPTED MANUSCRIPT
[9] J. V. Kingston, T. W. S. Jamieson and G. Wilkinson, J. Inorg. Nucl. Chem. 29(1967)
1
33-138.
[10] H. Walter, J. Peter. Chem. Ber. 103(1970) 2161-77.
[
11] (a) P. Chutia, N. Kumari, M. Sharma, J. D. Woollins, A. M. Z. Slawin, D. K. Dutta,
Polyhedron, 23(2004) 1657-1661. (b) E. Benedetti, G. Braca, G. Sbrana, F. Salvetti, B.
Grassi, J. Organometal. Chem. 37(1972) 361-373. (c) B. R. James, L. D. Markham, B.
C. Hui, G. L. Rempel, J. C. S. Dalton, (1973) 2247-2252. (d) A. O. Baghlaf, M. Ishaq,
A. K. A. Rashed, Polyhedron, 6(1987) 837-839. (e) I. O. Koshevoy, M. Haukka, T. A.
Pakkanen, S. P. Tunik, P. Vainiotalo, Organometallics, 24(2005) 3516-3526. (f) P.
Chutia, M. Sharma, P. Das, N. Kumari, J. D. Woollins, A. M. Z. Slawin, D. K. Dutta,
Polyhedron, 22(2003) 2725-2730. (g) M. R. Churchill, K. M. Keil, F. V. Bright, S.
Pandey, G. A. Baker, J. B. Keister, Inorg. Chem. 39(2000) 5807-5816. (h) S. Hermans,
B. F. G. Johnson, Chem. Commun. (2000) 1955-1956. (i) S. Fabre, P. Kalck, G.
Lavigne, Angew. Chem. Int. Ed. 36(1997) 1092-1095. (j) M. Ogasawara, F. Maseras,
N. Gallego-Planas, K. Kawamura, K. Ito, K. Toyota, W. E. Streib, S. Komiya, O.
Eisenstein, K. G. Caulton, Organometallics, 16(1997) 1979-1993. (k) G. M. Gray, A.
Varshney, C. H. Duffey, Organometallics, 14(1995) 238-244.
[
12] (a) D. W. Krassowski, J. H. Nelson, J. Organometal. Chem. 356(1988) 93-104. (b) R.
W. Wegman, A. G. Abatjoglou, A. M. Harrison. J. Chem. Soc., Chem. Commun.
(1987) 1891-1892. (c) S. J. Higgins, R. Taylor, B. L. Shaw. J. Organomet. Chem.,
3
25(1987) 285-292.
[
13] (a) L. M. Wilkes, J. H. Nelson, J. P. Mitchener, M. W. Babich, W. C. Riley, B. J.
Helland, R. A. Jacobson, M. Y. Cheng, K. Seff, L. B. McCusker, Inorg. Chem.
2
1(1982) 1376-1382. (b) C. F. J. Barnard, J. A. Daniels, J. Jeffrey, R. J. Mawby, J.
Chem. Soc. Dalton Trans. (1976) 953-961. (c) D. F. Gill, B. E. Mann, B. L. Shaw, J.
Chem. Soc. Dalton Trans. (1973) 311-317.
[
14] (a) Y. Shvo, E. Hazum, J. Chem. Soc. Chem. Commun. (1974) 336-337. (b) U.
Koelle, J. Organomet. Chem. 133(1977) 53-58. (c) D. J. Blumer, K. W. Barnett, T. L.
Brown, J. Organomet. Chem. 173(1979) 71-76. (d) D. St. C. Black, G. B. Deacon, N.
C. Thomas, Inorg. Chim. Acta, 54(1981) L143-L144.
1
5

ACCEPTED MANUSCRIPT
[15] G.-B. Ma, R. McDonald, M. Ferguson, R. G. Cavell, B. O. Patrick, B. R. James, T.
Q. Hu, Organometallics, 26(2007) 846-854.
[
16] M.-K. Chung, G. Ferguson, V. Robertson, M. Schlaf, Can. J. Chem. 79(2001) 949-
57.
9
[
17] P. S. Hallman, T. A. Stephenson, G. Wilkinson, Inorg. Synth. 12(1970) 237-240.
18] (a) H. D. Flack, Acta Crystallogr. A39(1983) 876-881. (b) H. D. Flack, G.
Bernardinelli, Acta Crystallogr. A55(1999) 908-915. (c) H. D. Flack, G.
Bernardinelli, J. Appl. Cryst. 33(2000) 1143-1148. (d) The Flack parameter refines
to a value near zero for the correct configuration of the structure, and to a value of
about one for the inverted configuration. The value observed herein is indicative of
racemic twinning, and was accommodated during the refinement using the
[
1
3c
SHELXL-93 TWIN instruction.
[
19] (a) Molecular Structure Corporation, 2001, D*TREK, Version 7.1I, MSC, 9009,
New Trails Drive, The Woodlands, TX, 77381-5209, USA. (b) G. M. Sheldrick,
Acta Crystallogr. A46(1990) 467-473. (c) G. M. Sheldrick, SHELXL-93. Program
for crystal structure determination. University of Göttingen, Germany, 1993.
20] A. A. Batista, J. Zukerman-Schpector, O. M. Porcu, S. L. Queiroz, M. P. Araujo,
Polyhedron, 13(1994) 689-693.
[
[
[
[
[
th
21] F. A. Cotton, G. Wilkinson, Advanced inorganic chemistry; 5 edn.; John Wiley &
Sons: New York, 1988, p.1299.
22] H. Doucet, T. Ohkuma, K. Murata, T. Yokozawa, M. Kozawa, E. Katayama, A. F.
England, T. Ikariya, R. Noyori, Angew. Chem. Int. Ed. 37(1998) 1703-1707.
23] S. L. Queiroz, A. A. Batista, G. Oliva, M. T. do Pi. Gambardella, R. H. A. Santos, K.
S. MacFarlane, S. J. Rettig, B. R. James, Inorg. Chim. Acta 267(1998) 209-221.
24] For example: (a) J.-X. Gao, T. Ikariya, R. Noyori, Organometallics 15(1996) 1087-
1
089. (b) O. M. Akotsi, K. Metera, R. D. Reid, R. McDonald, S. H. Bergens,
Chirality, 12(2000) 514-522. (c) S. Doherty, C. R. Newman, C. Hardacre, M.
Nieuwenhuyzen, J. G. Knight, Organometallics 22(2003) 1452-1462. (d) E. Lindner,
H. A. Mayer, I. Warad, K. Eichele, J. Organomet. Chem. 665(2003) 176-185. (e) E.
Lindner, I. Warad, K. Eichele, H. A. Mayer, Inorg. Chim. Acta 350(2003) 49-56. (f)
1
6

ACCEPTED MANUSCRIPT
C. G. Leong, O. M. Akotsi, M. J. Ferguson, S. H. Bergens, Chem Commun. (2003)
7
50-751 and (2003), 1779 (correction).
[
25] For example: (a) J.-H. Song, D.-J. Cho, S.-J. Jeon, Y.-H. Kim, T.-J. Kim, J. H. Jeong,
Inorg. Chem. 38(1999) 893-896. (b) P. K. Santra, C. Sinha, W.-J. Sheen, F.-L. Liao,
T.-H. Lu, Polyhedron 20(2001) 599-606. (c) T. Korenaga, K. Aikawa, M. Terada, S.
Kawauchi, K. Mikami, Adv. Synth. Catal. 343(2001) 284-288. (d) I. R. Butler, S. J.
Coles, M. Fontani, M. B. Hursthouse, E. Lewis, K. L. M. Abdul Malik, M. Meunier,
P. Zanello, J. Organomet. Chem. 637-639(2001) 538-548. (e) W.-K. Wong, X.-P.
Chen, J.-P. Guo, Y.-G. Chi, W.-X. Pan, W.-Y. Wong, J. Chem. Soc., Dalton Trans.
(2002) 1139-1146. (f) C. Nachtigal, S. Al-Gharabli, K. Eichele, E. Lindner, H. A.
Mayer, Organometallics 21(2002) 105-112. (g) B. G. Harvey, A. M. Arif, R. D.
Ernst, Polyhedron, 23(2004) 2725-2731. (h) M. O. Santiago, A. A. Batista, M. P. de
Araújo, C. L. Donnici, I. de S. Moreira, E. E. Castellano, J. Ellena, S. dos Santos, S.
Queiroz, Transition Met. Chem. 30(2005) 170-175.
[
26] M. P. de Araujo, A. T. de Figueiredo, A. L. Bogado, G. V. Poelhsitz, J. Ellena, E. E.
Castellano, C. L. Donnici, J. V. Comasseto, A. A. Batista, Organometallics, 24(2005)
6
159-6168.
[
27] (a) M. P. Magee, J. R. Norton, J. Am. Chem. Soc. 123(2001) 1778-1779. (b) R. M.
Bullock, Chem. Euo. J. 10(2004) 2366-2374. (c) T. Ikariya, K. Murata, R. Noyori,
Org. Biomol. Chem. 4(2006) 393-406. (d) S. E. Clapham, A. Hadzovic, R. H. Morris,
Coord. Chem. Rev. 248(2004) 2201-2237.
1
7

ACCEPTED MANUSCRIPT
II
Scheme 1. The synthesized cis-, cis-, trans- Ru Cl
2
(CO)
2
(R
3
P)
2
complexes
PR3
CH Cl2
CO
Cl
Cl
2
[
RuCl (CO) ]n
Ru
2 2
PR3
CO
PR3
PR = PH(C H )
11 2
(1)
(2)
(3)
(4)
3
6
PPh3
PPh (C F )
2
6 5
P(CH3)3
II
Scheme 2. The synthesized trans- Ru Cl
2
(DPPF)
2
(N)
2
complexes of (5), (6) and (7).
P
Cl
P
N
N
CH Cl
2
2
Fe
+ RuCl (PPh )
DPPF Ru
L
2
3 3
L
P
P
Cl
DPPF
L=
[RuCl (DPPF)(Ampy)] (5)
2
N
N
NH2
[
RuCl (DPPF)(Picam)] (6)
2
NH2
2
[RuCl (DPPF)(Py) ]
(7)
2
2
N
Scheme 3. Catalytic hydrogenation transfer reaction
O
OH
OH catalyst, KOH
0°C, N
O
+
+
8
2
1
8

ACCEPTED MANUSCRIPT
2 2 6 11 2 2
Figure 1. Perspective view of the cis-, cis-, trans-RuCl (CO) {(PH(C H ) } (1)
molecule showing the atom labeling scheme. Non-hydrogen atoms are
represented by Gaussian ellipsoids at the 20% probability level. The
phosphorus-bound hydrogen atoms are shown with arbitrarily small thermal
parameters; cyclohexyl group hydrogens are not shown.
1
9

ACCEPTED MANUSCRIPT
2
2
Figure 2. Perspective view of the [RuCl {k −Fe(C H PPh ) }(k −1, 10-phenanthroline)]
2
5
4
2 2
(9) molecule showing the atom labeling scheme. Non-hydrogen atoms are
represented by Gaussian ellipsoids at the 20% probability level. Hydrogen
atoms are not shown.
2
0

ACCEPTED MANUSCRIPT
Figure 3. Perspective view of the trans−[RuCl (PPh ) (2-picolylamine)] (8) molecule
2
3 2
showing the atom labeling scheme. Non-hydrogen atoms are represented by
Gaussian ellipsoids at the 20% probability level. Hydrogen atoms attached to
N2 and C6 are shown with arbitrarily small thermal parameters; all other
hydrogens are not shown.
2
1

ACCEPTED MANUSCRIPT
Table 1. Crystal data and structure refinement details for complex 1, 8 and 9
Empirical formula
Formula weight
C
26
H
46Cl
2
O
2
P
2
Ru (1) C H Cl N P Ru⋅2CH Cl
46 36 2 2 2
C H Cl FeN P Ru⋅2C
4
2
38
2
2
2
2
2
(
8)
H Cl (9)
2 2
624.54
Monoclinic
974.51
1076.38
Crystal system
Monoclinic
Monoclinic
Crystal Dimensions
0.55 × 0.49 × 0.17
mm
0.42 × 0.23 × 0.14 mm
0.18 × 0.18 × 0.09 mm
Space group
P21(No. 4)
P21/c (No. 14)
I2/a (an alternate
setting of C2/c (No. 15)
Unit cell parameters
a (Å)
b (Å)
c (Å)
β (°)
Volume (Å3)
Z
10.7266(15)
10.2196(14)
13.3443(19)
100.8700(19)
1436.6(3)
2
18.1129(11)
9.8700(6)
24.4824(15)
102.8701(8)
4266.9(5)
4
17.8675(14)
13.9858(11)
35.666(3)
94.1840(13)
8888.8(12)
8
Calculated density (g cm-3)
Temperature, K
µ (MoKα), (mm-1)
θ range for data collection (°)
Index ranges
1.444
193.2(1)
0.864
1.517
193.2(1)
0.853
1.609
193.2(1)
1.137
0.3 to 26.40
0.3 to 27.48
0.3 to 26.00
-
-
-
13 ≤ h ≤ 13
12 ≤ k ≤ 12
16 ≤ l ≤ 16
-23 ≤ h ≤ 23
-12 ≤ k ≤ 12
-31 ≤ l ≤ 31
9773
8046
9773/0/496
1.043
-22 ≤ h ≤ 22
-17 ≤ k ≤ 17
-43 ≤ l ≤ 43
8731
6267
8731/0/515
0.989
Independent reflections
Observed reflections
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices
5880
5697
5
880/8/448
1.053
[
F02 ≥ 2σ(F0)]
R1 = 0.0189
R1 = 0.0362
R1 = 0.0456
wR2 [F02 ≥ -3σ(F02)]
wR2 = 0.0496
wR2 = 0.0924
wR2 = 0.1017
Large difference peak and hole
-0.263 and 0.54 e/Å3 -1.062 and 0.881 e/Å3
-0.529 and 0.605 e/Å3
2
2

ACCEPTED MANUSCRIPT
Table 2. FTIR vibration data for the synthesized RuCl (CO) (P) and
2
2
2
RuCl (DPPF)(N-N) complexes.
2
3
1
Species
P(ppm)
ν(C≡O)
Refs
RuCl
RuCl
2
2
(CO)
(CO)
2
(PH(C
(P(CH
6
H
11
)
(4)
2
(1)
37.21
2035, 1974
2040, 1980
2055, 1991
2062, 2002
2145, 2073
2
3
)
3
)
2
16
20
RuCl (CO) (PPh ) (2)
RuCl (CO) P(C H ) (C F ) (3)
19.91
13.82
2
2
3 2
2
2
6
6 2
6 5
[RuCl (CO) ]
2 2 n
RuCl (CO) (Ph PX)
11a
2
2
3
2
X = O
2059, 1994
2054, 1991
2052, 1989
ν(N−H)
=
=
S
Se
RuCl (DPPF)(Ampy) (5)
32.34
52.1, 41.5
46.25
3298, 3188
3332, 3225
2
RuCl (DPPF)(Picam) (6)
2
2 2
RuCl (DPPF)(Py) (7)
Notes: All the IR data of compounds 1 to 4 were recorded from its pure solid phase in
the identical condition using a Nic-Plan FTIR Microscope Instrument.
2
3

ACCEPTED MANUSCRIPT
Table 3. Selected Bond Lengths (Å) and Angles (°) for
cis−RuCl (CO)(PH{C H } ) ) (1).
2 6 11 2 2
Ru-Cl(1A)
Ru-Cl(2A)
Ru-P(1)
2.4368(7)
2.4201(7)
2.4043(6)
2.4020(6)
1.862(3)
1.892(3)
1.847(2)
1.841(3)
1.36(2)
1.842(2)
1.852(3)
1.26(2)
1.141(4)
1.144(4)
Cl(1A)-Ru-Cl(2A) 94.71(3)
Cl(1A)-Ru-P(1)
Cl(1A)-Ru-P(2)
85.49(2)
93.07(3)
Ru-P(2)
Cl(1A)-Ru-C(1A) 178.78(9)
Ru-C(1A)
Ru-C(2A)
P(1)-C(11)
P(1)-C(21)
P(1)-H(1P)
P(2)-C(31)
P(2)-C(41)
P(2)-H(2P)
O(1A)-C(1A)
O(2A)-C(2A)
Cl(2A)-Ru-P(1)
Cl(2A)-Ru-P(2)
P(1)-Ru-P(2)
91.16(3)
86.97(3)
177.54(3)
2
4

ACCEPTED MANUSCRIPT
Table 4. Selected Bond Lengths (Å) and Angles (°) for trans-RuCl (DPPF)(Phen)
2
(
8).
Ru-N(1)
Ru-N(2)
Ru-Cl(1)
Ru-Cl(2)
Ru-P(1)
2.098(3)
2.117(3)
2.4567(10)
2.4183(10)
2.3130(10)
2.3608(10)
2.008(4)
2.031(4)
2.056(4)
2.056(4)
2.039(4)
2.020(4)
2.019(4)
2.057(4)
2.057(4)
2.040(4)
Cl(1)-Ru-Cl(2)
Cl(1)-Ru-P(1)
Cl(1)-Ru-P(2)
Cl(1)-Ru-N(1)
Cl(1)-Ru-N(2)
Cl(2)-Ru-P(1)
Cl(2)-Ru-P(2)
Cl(2)-Ru-N(1)
Cl(2)-Ru-N(2)
P(1)-Ru-P(2)
P(1)-Ru-N(1)
P(1)-Ru-N(2)
P(2)-Ru-N(1)
P(2)-Ru-N(2)
N(1)-Ru(1)-N(2)
86.91(4)
170.20(4)
86.92(3)
87.15(8)
83.35(8)
85.16(4)
94.00(3)
165.60(8)
87.68(8)
99.36(3)
99.22(8)
90.57(8)
98.76(8)
170.47(9)
78.61(11)
Ru-P(2)
Fe-C(10)
Fe-C(11)
Fe-C(12)
Fe-C(13)
Fe-C(14)
Fe-C(15)
Fe-C(16)
Fe-C(17)
Fe-C(18)
Fe-C(19)
2
5

ACCEPTED MANUSCRIPT
Table 5. Selected Bond Lengths (Å) and Angles (°) for Trans-RuCl (PPh ) (Picam)
2
3 2
(
9).
Ru-N(1)
Ru-N(2)
Ru-Cl(1)
Ru-Cl(2)
Ru-P(1)
Ru-P(2)
P(1)-C(11) 1.852(2)
P(1)-C(21) 1.843(3)
P(1)-C(31) 1.843(3)
P(2)-C(41) 1.842(2)
P(2)-C(51) 1.845(2)
P(2)-C(61) 1.864(2)
2.1482(19)
2.155(2)
2.4295(6)
2.4321(6)
2.3346(6)
2.3190(6)
Cl(1)-Ru-Cl(2)
Cl(1)-Ru-P(1)
Cl(1)-Ru-P(2)
Cl(1)-Ru-N(1)
Cl(1)-Ru-N(2)
Cl(2)-Ru-P(1)
Cl(2)-Ru-P(2)
Cl(2)-Ru-N(1)
Cl(2)-Ru-N(2)
P(1)-Ru-P(2)
P(1)-Ru-N(1)
P(1)-Ru-N(2)
P(2)-Ru-N(1)
P(2)-Ru-N(2)
N(1)-Ru(1)-N(2)
164.89(2)
88.29(2)
104.91(2)
80.65(6)
83.86(6)
93.58(2)
89.64(2)
94.61(6)
81.07(6)
98.75(2)
165.19(5)
92.88(6)
93.62(6)
165.55(6)
76.26(8)
N(1)-C(1)
N(2)-C(6)
C(1)-C(6)
1.354(3)
1.484(3)
1.492(4)
2
6

ACCEPTED MANUSCRIPT
a
Table 6. Catalyzed hydrogenation transfer reduction of acetophenone
Precursor catalysts
Reaction time (h)
Conversion (%)
a
RuCl (PH(C H ) ) (CO) (1)
24
24
24
24
24
24
90.4
2
6
11 2 2
2
a
RuCl (PPh ) (CO) (2)
76.3
2
2
2
3 2
2
a
RuCl
RuCl
(PPh
2
(C
6
F
5
))
2
(CO)
2
(3)
60.8
b
(DPPF)(Ampy)
2
(5)
17.0
b
RuCl (DPPF)(Picam) (6)
90.0
2
b
RuCl (DPPF)(Py) (7)
42.2
2
a
b
Experimental condition: in 2-propanol, under N , 80°C, KOH Cat:Base:S = 1:20:500,
2
Cat:Base:S = 1:20:1000.
2
7

ACCEPTED MANUSCRIPT
Highlights
•
Two types of Ru(II) pre-catalysts (type I and type II) were designed
and synthesized.
•
All Ru(II) complexes were fully characterized and two new crystal
structures were determined in solid.
•
The hydrogenation transfer reactivity of all synthesized Ru(II) pre-
catalysts were tested under the same conditions.
•
Our tested results demonstrate that CO bonding to Ru(II) is less
efficient hydrogen transfer catalyst than nitrogen bonding.