Half-sandwich η6-arene-ruthenium(II) complexes bearing 1-alkyl(benzyl)-imidazo[4,5-f][1,10]-phenanthroline (IP) derivatives: The effect of alkyl chain length of ligands to catalytic activity

Article abstract of DOI:10.1016/j.tet.2013.09.023

The reaction of bromoalkanes (R-Br; (3), R=C_nH_2n+1, n=4 (a), 8 (b), 12 (c),18 (d)) and bromobenzyl derivatives (R′-Br; (4), R′=CH₂C₆H₂(CH₃) ₃-2,4,6 (a); CH₂C₆H(CH₃) ₄-2,3,5,6 (b); CH₂C₆(CH₃) ₅ (c)) with 1H-imidazo[4,5-f][1,10]-phenanthroline (IP)(L ₂) gave the corresponding 1-R-imidazo[4,5-f][1,10]-phenanthroline (IPR)(L_3a-d) and 1-R′-imidazo[4,5-f][1,10]-phenanthroline(IPR') (L_4a-c) ligands, respectively. Treatment of L_3a-d and L_4a-d with [Ru(p-cymene)Cl₂]₂ led to the formation of [Ru(p-cymene)(IPR)Cl]Cl (RuL_3a-d) and [Ru(p-cymene)(IPR′)Cl]Cl (RuL_4a-c). New ruthenium(II) complexes RuL_3a-d and RuL_4a-c were characterized by elemental analysis, FTIR, UV-visible and NMR spectroscopy. In order to understand effects of these changes on the N-substituent of imidazol on IP and how they translate to catalytic activity, these new RuL₂, RuL_3a-d and RuL_4a-c were applied in the transfer hydrogenation of ketones by 2-propanol in presence of potassium hydroxide. The activities of the catalysts were monitored by NMR and GC analysis.

Full text of DOI:10.1016/j.tet.2013.09.023

Tetrahedron 69 (2013) 10669e10674
Contents lists available at ScienceDirect
Tetrahedron
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Half-sandwich
h
6-areneeruthenium(II) complexes bearing
1-alkyl(benzyl)-imidazo[4,5-f][1,10]-phenanthroline (IP) derivatives:
the effect of alkyl chain length of ligands to catalytic activity
*
€
€
€
Lutfiye Gok, Hayati Turkmen
Department of Chemistry, Ege University, 35100 Bornova-Izmir, Turkey
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 26 April 2013
Received in revised form 27 August 2013
Accepted 9 September 2013
Available online 14 September 2013
The reaction of bromoalkanes (ReBr; (3), R¼CnH2nþ1, n¼4 (a), 8 (b), 12 (c),18 (d)) and bromobenzyl
derivatives (R0eBr; (4), R0¼CH2C6H2(CH3)3-2,4,6 (a); CH2C6H(CH3)4-2,3,5,6 (b); CH2C6(CH3)5 (c)) with
1H-imidazo[4,5-f][1,10]-phenanthroline (IP)(L2) gave the corresponding 1-R-imidazo[4,5-f][1,10]-phe-
nanthroline (IPR)(L3aed) and 1-R0-imidazo[4,5-f][1,10]-phenanthroline(IPR’)(L4aec) ligands, respectively.
Treatment of L3aed and L4aed with [Ru(p-cymene)Cl2]2 led to the formation of [Ru(p-cymene)(IPR)Cl]Cl
(RuL3aed) and [Ru(p-cymene)(IPR0)Cl]Cl (RuL4aec). New ruthenium(II) complexes RuL3aed and RuL4aec
were characterized by elemental analysis, FTIR, UVevisible and NMR spectroscopy. In order to un-
derstand effects of these changes on the N-substituent of imidazol on IP and how they translate to
catalytic activity, these new RuL2, RuL3aed and RuL4aec were applied in the transfer hydrogenation of
ketones by 2-propanol in presence of potassium hydroxide. The activities of the catalysts were monitored
by NMR and GC analysis.
Keywords:
Areneeruthenium(II) complexes
1H-Imidazo[4,5-f][1,10]-phenanthroline
Transfer hydrogenation
Half-sandwich complexes
Ó 2013 Elsevier Ltd. All rights reserved.
1. Introduction
ruthenium complexes. First, steric and electronic effects around the
Ru core can be finally tuned by an appropriate selection of bulky
Half-sandwich
h
6-areneeruthenium(II) complexes are well
and/or electron withdrawing or donating substituents incorporated
into the nitrogenous ligands. Secondly, nitrogen-containing ligands
are currently prepared in high yield.17 Thus, ruthenium complexes
containing nitrogen donor ligands have been extensively in-
vestigated in the last two decades because of their properties
developed and have a wide range of applications as catalyst pre-
cursors for transfer hydrogenation (TH),1e7 ring opening metathesis
polymerization,8 and olefin oxidation.9,10
In addition, they have been extensively investigated for their
potent antibacterial and anticancer activity.11,12 Moreover, are-
neeruthenium compounds belong to a well-established family of
robust metaleorganic molecules (metal¼Ru(II), Rh(III) and Ir(III)),
which are soluble and stable in water,13 with many potential ad-
vantages such as alleviation of environmental problems associated
with the use of organic solvents, industrial applications with the
introduction of new biphasic processes14 and metal-mediated
organic syntheses in water.15
They have emerged as versatile organometallic intermediates in
organic synthesis as a consequence of the ease with which the
arene ligand can be functionalized.16 The presence of the aromatic
-ligand stabilizes and protects the metal centre, preventing
rapid oxidation to ruthenium(III). Examples of arene ligands have
included benzene, p-cymene and hexamethylbenzene.
and usefulness, particularly in catalysis.18 Half-sandwich
h
6-are-
neeruthenium(II) complexes containing dinitrogen ligands have
shown excellent activities in the reduction of ketones and imines,
leading to secondary alcohols and amines.19 On the other hand,
1,10-phenanthroline (phen) is a classic chelating bidentate ligand
for transition metal ions that has played an important role in the
development of coordination chemistry,20,21 and still continues to
be of considerable interest as versatile starting material for organic,
inorganic and supramolecular chemistry. Phen is a rigid planar,
hydrophobic, electron-poor heteroaromatic system whose nitrogen
atoms are beautifully placed to act cooperatively in cation binding.
These structural features determine its coordination ability towards
metal ions. The increasing interest in the chemistry of phen de-
rivatives has prompted the development of efficient synthetic
procedures for the chemical functionalization of the phen nucleus
at the various ring positions. The 5- and 6-positions of phen are the
most susceptible to electrophilic substitutions. 1H-Imidazo[4,5-f]
[1,10]-phenanthroline (IP) is an important derivative of phen that
has been used to recognize the secondary structure of DNA in
p
For several reasons, nitrogen-containing ligands have been
found to be among the most convenient and attractive ligands for
* Corresponding
author.
E-mail
address:
hayatiturkmen@hotmail.com
€
(H. Turkmen).
0040-4020/$ e see front matter Ó 2013 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.tet.2013.09.023

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L. Gok, H. Turkmen / Tetrahedron 69 (2013) 10669e10674
10670
ruthenium(II) complexes.22 Due to the presence of aromatic/het-
erorings of IP, the delicate stacking interactions are available
to play a pivotal role in adjusting the resulting supramolecular
structures, this property being critical in constructing and stabi-
lizing the complex is important in catalytic activity. The electron-
rich conjugated ring of IP indicates that its metal complexes may
also be applied in TH of ketones.
band to a specific vibration has not been attempted. The presence of
p
ep
the eC]Negroup in complexes was verified with n(C]N) vibra-
tions between 1602 and 1449 cmꢀ1 (Table 1).
Table 1
Comparison of selected spectroscopic data of complexes RuL3aed, RuL4aec
Entry Complex IR (
n
, cmꢀ1
)
UVevisible (nm)
DTG/peak
temperature (ꢁC)
The main aim of this study was to investigate the influence of the
steric and electronic properties of
h
6-areneeruthenium(II) com-
1
2
3
4
5
6
7
8
9
RuL1
RuL2
1410, 1526, 1650 244, 317, 350, 405 260, 503
1443, 1536, 1605 261, 301, 395, 411 305, 633
1451, 1526, 1601 257, 300, 388, 404 216, 400, 621
1449, 1524, 1601 259, 300, 388, 406 210, 400, 650
1449, 1524, 1601 257, 299, 389, 404 200, 383, 646
1451, 1526, 1601 259, 300, 388, 406 201, 366, 680
1450, 1521, 1602 257, 303, 388, 405 224, 330, 628
1450, 1521, 1601 259, 300, 387, 405 225, 338, 612
1450, 1521, 1602 258, 302, 387, 406 230, 310, 600
plexes bearing the IP or its alkyl, benzyl derivatives employed in the
transfer hydrogenation of ketones. Our experiments suggested that
the chain lengths of alkyl groups on IP of complexes influence cat-
alytic activity of TH. This observation has been made for the first time
for cationic complexes, which are single ruthenium catalysts.
RuL3a
RuL3b
RuL3c
RuL3d
RuL4a
RuL4b
RuL4c
2. Results and discussion
2.1. Synthesis, characterization of ligands and their
complexes
The electronic spectra of the ruthenium complexes RuL3aed
RuL4aec in dichloromethane at room temperature showed
medium-intensity bands around 405e403 nm range due to metal-
,
The IP-functionalized ligands were synthesized according to the
steps illustrated in Scheme 1. Starting from phenanthroline, 1,10-
phenanthroline-5,6-dione (L1) was synthesized and was then
converted to benzimidazole derivatives using ring closing process
1H-imidazo-[4,5-f][1,10] phenanthroline (L2) and as a result of
an effect of interaction this ligand with different alkyl and
benzyl bromides in basic medium 1-alkyl-imidazo-[4,5-f] [1.10]
to-ligand charge transfer transitions (MLCT) and intense ne
ligand-centred transitions bands with maxima in the
389e256 nm range (Table 1).
p ,
*
pep
*
In order to examine thermal stability of the ruthenium com-
plexes, TGA measurement of complexes were carried out (Fig. SI-1,
Supplementary data). The plots showed the weight loss (w57%) as
a function of increasing temperature. For RuL3aec, RuL4aec com-
plexes, the small weight loss (w6%) just below 110 ꢁC is due to the
loss of included solvent molecules (Table 1). The first stage of
phenanthroline(IPR)(L3aed
)
and 1-benzyl-imidazo-[4,5-f][1.10]
phenanthroline (IPR’) (L4aec) were synthesized. All ligands have
been isolated as colourful and air stable solids.
Scheme 1. Synthesis of ligands and complexes.
[Ru(p-cymene)IPR(R0)Cl]Cl (RuL3aed, RuL4aec) complexes were
synthesized by reaction of [Ru(p-cymene)Cl2]2 with the IPR ligands
(L3aed) or IPR0 (L4aec) in CH2Cl2. All new complexes RuL3aed, RuL4aec
have been isolated as orange and air stable solids. They are soluble in
water, ethanol and DMSO. The new ligands and complexes were
characterized by 1H and 13C NMR spectroscopy. In 1H NMR spectra,
decomposition in complexes occurred in the temperature range
150e340 ꢁC. This decomposition in all cases reflected a weight loss of
approximately 20%, which is due to the loss of p-cymene units. For
IPR(R0) the initial significant decomposition occurred in the tem-
perature range 340e680 ꢁC. The lower thermal stabilities of RuL3aed
complexes may be attributed to a long alkyl chain on IP. These ob-
servations further confirm that the electron-donating nature of alkyl
substituent on the IP has a marked influence on the metaleligand
interactions, which could have an effect on catalyst life time.
the CeH signals of imidazol on L3aed
served to shift slightly to lower field as compared to their signals in
L4aec
7.38e7.41 ppm). The 1H NMR spectra of complexes showed
(d 7.92e7.90 ppm) were ob-
(d
some differences from their respective ligands. The benzylic-CH2
protons of RuL4aec were observed to shift towards lower fields as
compared to respective ligands.
2.2. Catalytic screening
IR spectra of RuL3aec, RuL4aec showed many bands of varying
In this report, we extend half-sandwich ruthenium complexes
with phen-based bidentate N^N ligands and compare their
intensities within 4000e400 cmꢀ1. Assignment of each individual

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L. Gok, H. Turkmen / Tetrahedron 69 (2013) 10669e10674
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efficiencies in TH reactions. The behaviour of the complexes (RuL1,
RuL2, RuL3aed, RuL4aec) in the transfer hydrogenation of aceto-
phenone in the presence of KOH by 2-propanol (IPA) was studied.
To investigate the influence of auxiliary ligands on RuL1, RuL2,
RuL3aed, RuL4aec, we applied a low catalyst loading (0.01 mmol, at
80 ꢁC) (Fig. 1). After 30 min, a 98% yield was achieved for the
preparation of 1-phenylethanol by using complex RuL3d. Over
Previously, the beneficial effect of donor substituents at the
arene ligand was studied by Suss-Fink et al. and Reanaud et al.23 So,
€
0
00
the complexes RuL3d ; RuL3d were prepared from ligand L3d and
[RuCl2(
h
6-C6(Me)6)]2, RuCl2(DMSO)4, respectively. They observed
that p-cymene ligand gave the best result on TH. The effects of
C6(Me)6 and p-cymene ligands were explored and it was proposed
that p-cymene ligand is the best comprise between steric effects
and electron density on the ruthenium. We also tested the catalytic
activity in the presence of free p-cymene but the yield did not
change significantly (Scheme 2).
a
30 min period, the catalytic activity decreased in order
RuL3d>RuL3c>RuL3b>RuL3a>RuL4c>RuL4b>RuL4a>RuL2>RuL1.
As in the previous studies, the best results were obtained with KOH.
The other bases NaOH, Na2CO3, K2CO3, Et3N, Pyridine (Py) were
investigated in TH. But, a longer time was necessary for reasonable
conversions. Transfer hydrogenation of ketones was not observed
in the absence of a base. When the catalyst loading decreased,
a slightly lower yield was obtained. The catalyst performance at
lower temperature afforded moderate yield. Among the various
solvents explored; EtOH, IPA-H2O, ethanediol (C2H6O2), the best
were obtained in IPA. To test the effect of temperature on catalyst
(RuL3d) performance, the catalytic reaction was performed at 50 ꢁC.
As shown in Table 2 (entry 7), the lower yield was obtained com-
pared to higher temperature (82 ꢁC, entry 1) as expected.
Scheme 2. (i) DCM, [RuCl2(h
6-C6(Me)6)]2; (ii) DCM, RuCl2(DMSO)4.
We explored the effectiveness of catalyst RuL3d on other aryl
and alkyl ketones (Table 3). The catalyst RuL3d gave good results
when electron-donating (OMe) and electron withdrawing (Cl, Br)
substituents were present at the para- or ortho-position of the aryl
ring of ketone. In addition to this, we indicated that catalyst RuL3d
was effective for the reduction of not only aromatic ketones but also
aliphatic ketones. The amphiphilic catalyst RuL3d bearing a long
alkyl chain on IP, may favour the formation of metallomicelles,
leading to strongly hydrophobic interaction between the chain of
the catalyst and the alkyl chain of the substrate in the core.
Therefore, synergistic effects between the metal-catalyzed centre
and substrate facilitate the reduction. We found that the alkyl
length of aliphatic ketones greatly influenced the reactivity (entries
8e11).
We also performed an additional experiment to assess whether
the reaction system is homogeneous or heterogeneous and Hg(0)-
poisoning test was carried out. The suppression of catalysis by
Hg(0) is evidence for a heterogeneous catalyst; if Hg(0) does not
suppress catalysis, that is, evidence for a homogeneous catalyst.24
The Hg(0) test with catalyst RuL3d and acetophenone in basic IPA
showed no significant inhibition of conversion to products. A
negative result for the mercury test can confirm a homogeneous
catalytic system (Table 4).
Fig. 1. Catalytic transfer hydrogenation of acetophenone catalyzed by ruthenium(II)
complexes by GC.
Table 2
Screening of reaction conditions
Entry Ru(L)
% Cat Solvent Base
Temperature Yield
(ꢁC)
(%)
1
2
3
4
5
6
7
8
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
RuL3d
1
1
1
1
1
1
1
1
IPA
IPA
IPA
IPA
IPA
IPA
IPA
EtOH
H2O
KOH
82
100
81
57
63
17
21
28
32
18
13
68
42
17
84
36
9
3. Conclusion
NaOH 82
K3PO4 82
K2CO3 82
Et3N
Py
KOH
KOH
KOH
In this work, the preparation and characterization of ligands
containing IP and their Ru(II) complexes and their catalytic activi-
ties for the hydrogen transfer reaction of ketones were presented.
The activities of ruthenium(II) complexes have been explained on
the basis of electron-donating groups present on the IPR(R0) and
electronic effects about metal centre. It was observed that the
presence of the alkyl chain or benzyl derivative on imidazol of the
IP increases the electron density on the metal centre and the rate of
transfer hydrogenation. Synthetic, spectroscopic, and computa-
tional studies are now underway to (i) further modify the IP
framework in order to determine what features are key to im-
proving catalyst performance, with an emphasis on understanding
82
82
50
78
82
82
82
82
82
82
82
82
82
82
82
9
1
1
11
12
13
14
15
16
17
18
19
20
C2H6O2 KOH
IPA
IPA
0.1
0.01
0.001 IPA
1
1
KOH
KOH
KOH
KOH
KOH
KOH
KOH
KOH
KOH
0
IPA
IPA
IPA
IPA
IPA
IPA
00
[RuCl2(
[RuCl2(
RuCl2DMSO4
None
h
h
6-p-cymene)]2 0.5
6-C6Me6)]2
0.5
1
42
30
7
steric effects, (ii) explore whether the phenanthroline-based
system can interact with the ruthenium centre and stabilize the
active species.
p-
d
Catalytic conditions: substrate (1 mmol), base (0.1 mmol), IPA (5 mL), 30 min.

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L. Gok, H. Turkmen / Tetrahedron 69 (2013) 10669e10674
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Table 3
Elmer Spectrum 100 series and UV spectra were on PG T60
UVevisible spectrophotometer. Elemental analyses were per-
formed on Perkin Elmer PE 2400 elemental analyzer. The yields of
catalytic experiments were measured by GC (Agilent Technologies
6890N-Thermo-Finnigan on HP-5 capillary column and equipped
a FID detector). Thermogravimetric (TG) and differential ther-
mogravimetric (DTG) curves were obtained using a PerkineElmer
Pyris 6 analyzer in the range 50e950 ꢁC in ceramic crucibles under
Catalytic transfer hydrogenation of different ketones in IPA with RuL3d
Entry
1
Ketone
Alcohol
Conversiona (%)
98
nitrogen (flux rate: 20 cm3 minꢀ1) at a heating rate of 20 ꢁC minꢀ1
.
4.2. General procedure for the preparation of ligands
2
3
80
97
IP (2.00 g, 9.10 mmol) and KOH (0.61 g, 11.0 mmol) were dis-
solved in acetone. The mixture was stirred and heated under reflux
for 1 h. Then, different aryl or alkyl bromides (9.10 mmol) were
added and kept on refluxing for 48 h. The volatiles were removed
under vacuum and then the residue was dissolved with DCM
(5.00 mL) and filtered with cannula. Diethylether was added to the
solution. Obtained light brown precipitate was filtered and dried
under vacuum.
4
5
64
95
4.3. General procedure for the preparation of ruthenium(II)
complexes
6
7
81
82
[Ru(p-cymene)Cl2]2 (0.17 g, 0.28 mmol) was added to a solution
of IPR (0.55 mmol) in DCM (5.00 mL), the mixture was stirred for
2 h at room temperature. The volatiles were removed under vac-
uum the yellow solid was washed with diethylether. The desired
product was dried under vacuum.
8
9
100b
100
4.3.1. Compound L3a. Yield: 1.80 g, 72%. 1H NMR (400 MHz, CDCl3):
d
9.15 (dd, J¼4.4, 2.0 Hz, 1H, pheneH), 9.13 (dd, J¼4.4, 1.6 Hz, 1H,
pheneH), 8.97 (dd, J¼8.4, 2.0 Hz, 1H, pheneH), 8.44 (dd, J¼8.2,
1.6 Hz, 1H, pheneH), 7.92 (s, 1H, C2eH), 7.72 (dd, J¼8.0, 4.0 Hz, 1H,
pheneH), 7.64 (dd, J¼8.0, 4.4 Hz, 1H, pheneH), 4.52 (t, J¼7.2 Hz, 2H,
butyleCH2), 1.97 (m, J¼7.4 Hz, 2H, butyleCH2), 1.46 (m, 2H,
butyleCH2), 0.99 (t, J¼7.4 Hz, 3H, butyleCH3). 13C NMR (100 MHz,
10
100
100
CDCl3):
d 148.80, 148.0, 145.0, 144.3, 144.1, 137.2, 130.1, 129.7, 124.5,
124.2, 124.0, 120.3, 47.30, 32.3, 19.7, 14.1. IR, nmax (CH2Cl2): 3394,
2927, 2852, 1737, 1564, 1522, 1396, 1353, 1079, 806, 741. Anal. Calcd
for C17H16N4 (M¼276.14): C, 73.89; H, 5.84; N, 20.27. Found: C,
73.78, H, 5.80, N, 20.22%.
11
a
Catalytic condition: substrate (1 mmol), RuL3d (0.01 mmol), KOH (0.1 mmol),
IPA (5 mL), 30 min. Conversion determined by GC and NMR analysis. [S]/[cat]¼100.
b
Conversion time 15 min.
4.3.2. Compound L3b. Yield: 2.50 g, 83%. 1H NMR (400 MHz, CDCl3):
d
9.16 (dd, J¼4.3, 1.8 Hz, 1H, pheneH), 9.12 (dd, J¼4.3, 1.5 Hz, 1H,
pheneH), 8.95 (dd, J¼8.1, 1.8 Hz, 1H, pheneH), 8.39 (dd, J¼8.4,
1.5 Hz, 1H, pheneH), 7.90 (s, 1H, C2eH), 7.71 (dd, J¼8.1, 4.3 Hz, 1H,
pheneH), 7.61 (dd, J¼8.3, 4.3 Hz, 1H, pheneH), 4.47 (t, J¼7.2 Hz, 2H,
octyleCH2), 1.96 (m, 2H, octyleCH2), 1.31 (m, 10H, octyleCH2), 0.86
Table 4
The Hg poisoning test for TH of acetophenone to 1-phenylethanol
Entry
RuL3d/Hg0
Conversion (%)
1
2
3
1:0
1:1
1:300
100
100
95
(t, J¼6.8 Hz, 3H, octyleCH3). 13C NMR (100 MHz, CDCl3):
d 148.9,
147.9, 144.9, 144.2, 142.9, 137.6, 130.2, 128.2, 124.4, 123.8, 123.6,
122.6, 119.9, 48.1, 31.8, 30.21, 29.2, 29.1, 26.7, 22.7, 14.1. IR, nmax
(CH2Cl2): 3392, 2926, 2854, 1568, 1523, 1452, 1398, 1351, 1081, 809,
742. Anal. Calcd for C21H24N4 (M¼332.44): C, 75.87; H, 7.28; N,
16.85. Found: C, 75.84; H, 7.19; N, 16.68%.
4. Experimental
4.1. General
4.3.3. Compound L3c. Yield: 2.80 g, 81%. 1H NMR (400 MHz, CDCl3):
d
9.16 (dd, J¼4.3, 1.8 Hz, 1H, pheneH), 9.13 (dd, J¼4.3, 1.6 Hz, 1H,
All manipulations were performed in air. The solvents were used
as received. The reagents were purchased from SigmaeAldrich,
Merck, Alfa Aesar and Acros Organics. The compounds L1, L2, RuL1,
RuL2 were prepared according to the literature methods.25,26 1H,
13C NMR spectra were recorded with a Varian AS 400 Mercury in-
strument. As solvent, CDCl3 and DMSO were employed. Chemical
pheneH), 8.96 (dd, J¼8.1, 1.8 Hz, 1H, pheneH), 8.40 (dd, J¼8.4,
1.6 Hz, 1H, pheneH), 7.90 (s, 1H, C2eH), 7.71 (dd, J¼8.1, 4.3 Hz, 1H,
pheneH), 7.62 (dd, J¼8.4, 4.3 Hz, 1H, pheneH) 4.49 (t, J¼7.3 Hz, 2H,
dodecyleCH2), 1.97 (m, 2H, dodecyleCH2), 1.24 (m, 18H, dode-
cyleCH2), 0.87 (t, J¼6.8 Hz, 3H, dodecyleCH3). 13C NMR (100 MHz,
CDCl3):
d 148.9, 147.8, 144.7, 144.2, 142.8, 137.5, 130.2, 128.2, 124.4,
shifts (
d
) are given in parts per million (ppm) and coupling con-
123.7, 123.6, 122.6, 119.8, 48.0, 32.0, 30.1, 29.7, 29.6, 29.5, 29.4, 29.1,
stants (J) in hertz (Hz). FTIR spectra were recorded on a Perkin
26.6, 22.7, 14.2, 14.1. IR, nmax (CH2Cl2): 3392, 2924, 2853, 1561, 1522,

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L. Gok, H. Turkmen / Tetrahedron 69 (2013) 10669e10674
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1466, 1396, 1351, 1078, 804, 741. Anal. Calcd for C25H32N4
(M¼388.55): C, 77.28; H, 8.30; N, 14.42. Found; C, 77.18; H, 8.18; N,
14.33%.
1601, 1526, 1451, 1403, 811, 724. Anal. Calcd for C27H26Cl2N4Ru
(M¼578.50): C, 56.06; H, 4.53; N, 9.68. Found C, 56.03; H, 4.49; N,
9.61%.
4.3.4. Compound L3d. Yield: 3.70 g, 87%. 1H NMR (400 MHz, CDCl3):
4.3.9. Complex RuL3b. Yield: 0.31 g, 90%. 1H NMR (400 MHz,
d
9.16 (dd, J¼4.3, 1.7 Hz, 1H, pheneH), 9.13 (dd, J¼4.3, 1.4 Hz, 1H,
CDCl3):
d
10.40 (d, J¼5.2 Hz, 1H, pheneH), 10.24 (d, J¼4.9 Hz, 1H,
pheneH), 8.96 (dd, J¼8.1, 1.6 Hz, 1H, pheneH), 8.43 (dd, J¼8.3,
1.5 Hz, 1H, pheneH), 7.92 (s, 1H, C2eH), 7.71 (dd, J¼8.1, 4.3 Hz, 1H,
pheneH), 7.63 (dd, J¼8.4, 4.3 Hz, 1H, pheneH), 4.51 (t, J¼7.2 Hz, 2H,
octadecyleCH2), 1.98 (m, 2H, octadecyleCH2), 1.24 (m, 30H, octa-
decyleCH2), 0.87 (t, J¼6.8 Hz, 3H, octadecyleCH3). 13C NMR
pheneH), 9.08 (d, J¼8.1 Hz, 1H, pheneH), 8.82 (d, J¼8.5 Hz, 1H,
pheneH), 8.28 (dd, J¼8.4, 5.3 Hz, 1H, pheneH), 8.16 (dd, J¼8.5,
4.3 Hz, 1H, pheneH), 8.13 (s, 1H, C2eH), 6.48 (dd, J¼10.8, 6.2 Hz, 2H,
C
10H14(C6H4)), 6.33 (dd, J¼9.4, 6.3 Hz, 2H, C10H14(C6H4)), 4.58 (t,
J¼7.3 Hz, 2H, octyleCH2), 2.71 (m, 1H, C10H14(CH(CH3)2)), 2.30 (s,
3H, C10H14(CH3)), 1.93 (m, 2H, Hz, octyleCH2), 1.26 (m, 10H,
octyleCH2), 0.97 (d, J¼6.8 Hz, 6H, C10H14(CH(CH3)2)), 0.83 (t,
(100 MHz, CDCl3):
d 149.0, 148.0, 144.9, 144.3, 142.9, 137.7, 130.3,
128.3, 124.5, 123.8, 123.7, 122.7, 119.9, 48.2, 32.1, 30.2, 29.8, 29.7,
29.6, 29.5, 29.2, 26.7, 22.8, 14.2. IR, nmax (CH2Cl2): 3374, 2923, 2849,
1560,1519,1463,1398,1361,1081, 803, 743. Anal. Calcd for C31H44N4
(M¼472.71): C, 78.77; H, 9.38; N, 11.85. Found C, 78.70; H, 9.32; N,
11.78%.
J¼6.7 Hz, 3H, octyleCH3). 13C NMR (100 MHz, CDCl3):
d 155.3, 145.1,
143.9, 143.8, 137.8, 132.5, 131.1, 127.1, 126.1, 124.4, 121.4, 104.9, 104.3,
87.3, 87.2, 84.8, 84.5, 48.3, 31.7, 31.2, 30.0, 29.1, 29.0, 26.6, 22.6, 22.2,
19.2, 14.1. IR, nmax (CH2Cl2): 2964, 2927, 1738, 1522, 1477, 1443, 1383,
1060, 821, 757. Anal. Calcd for C31H34Cl2N4Ru (M¼634.60): C, 58.67;
H, 5.40; N, 8.83. Found C, 58.59; H, 5.27; N, 8.76%.
4.3.5. Compound L4a. Yield: 2.60 g, 90%. 1H NMR (400 MHz, CDCl3):
d
9.19 (dd, J¼14.3, 3.0 Hz, 2H, pheneH), 8.98 (d, J¼8 Hz, 1H,
pheneH), 8.90 (d, J¼8.2 Hz, 1H, pheneH), 7.73 (m, 2H, pheneH),
7.38 (s, 1H, C2eH), 7.04 (s, 2H, AreH), 5.74 (s, 2H, AreCH2), 2.38 (s,
3H, AreCH3), 2.29 (s, 6H, AreCH3). 13C NMR (100 MHz, CDCl3):
4.3.10. Complex RuL3c. Yield: 0.33 g, 87%. 1H NMR (400 MHz,
CDCl3):
d
10.36 (d, J¼4.7 Hz, 1H, pheneH), 10.08 (d, J¼4.4 Hz, 1H,
pheneH), 9.08 (d, J¼7.6 Hz, 1H, pheneH), 8.79 (d, J¼8.1 Hz, 1H,
pheneH), 8.29 (dd, J¼8.2, 5.2 Hz, 1H, pheneH), 8.13 (dd, J¼8.1,
5.2 Hz, 1H, pheneH), 8.09 (s, 1H, C2eH), 6.48 (d, J¼5.9 Hz, 1H,
d
149.0, 148.0, 145.0, 144.2, 140.7, 139.6, 138.0, 137.7, 130.36, 130.0,
128.7, 126.6, 124.8, 124.5, 123.6, 122.7, 120.5, 47.3, 21.2, 19.5. IR, nmax
(CH2Cl2): 3376, 2969, 2849, 1737, 1562, 1518, 1349, 1217, 1006, 804,
742. Anal. Calcd for C23H20N4 (M¼352.43): C, 78.38; H, 5.72; N,
15.90. Found C, 78.26; H, 5.64; N, 15.72%.
C
10H14(C6H4)), 6.38 (d, J¼6.0 Hz, 1H, C10H14(C6H4)), 6.31 (d,
J¼5.5 Hz, 1H, C10H14(C6H4)), 6.25 (d, J¼5.6 Hz, 1H, C10H14(C6H4)),
4.57 (t, J¼7.3 Hz, 2H, dodecyleCH2), 2.71 (m, 1H, C10H14(CH(CH3)2)),
2.46 (s, 3H, C10H14(CH3)), 1.23 (m, 20H, dodecyleCH2), 0.98 (d,
J¼6.9 Hz, 6H, C10H14(CH(CH3)2)), 0.87 (t, J¼7.0 Hz, 3H, dode-
4.3.6. Compound L4b. Yield: 2.70 g, 81%. 1H NMR (400 MHz, CDCl3):
d
9.22 (d, J¼4.3 Hz, 1H, pheneH), 9.18 (dd, J¼4.3, 1.7 Hz, 1H,
cyleCH3). 13C NMR (100 MHz, CDCl3):
d 155.0, 145.1, 143.9, 137.7,
pheneH), 8.98 (dd, J¼8.1, 1.6 Hz, 1H, pheneH), 8.91 (d, J¼8.3 Hz, 1H,
pheneH) 7.73 (m, 2H, pheneH), 7.38 (s, 1H, C2eH), 7.15 (s, 1H,
PheH), 5.81 (s, 2H, AreCH2), 2.32 (s, 6H, AreCH3), 2.20 (s, 6H,
132.6, 131.2, 127.2, 127.1, 126.1, 124.4, 121.4, 104.9, 104.3, 87.3, 87.2,
84.8, 84.5, 48.3, 32.0, 31.2, 30.0, 29.7, 29.6, 29.5, 29.4, 29.2, 26.6,
22.8, 22.3, 19.2, 14.2. IR, nmax (CH2Cl2): 2923, 2853, 1736, 1601, 1517,
AreCH3). 13C NMR (100 MHz, CDCl3):
d
149.1, 148.10, 145.1, 144.3,
1449, 1216, 1033, 875, 726. Anal. Calcd for C35H42Cl2N4Ru
141.1, 137.8, 137.5, 135.1, 134.1, 133.3, 130.4, 129.4, 128.7, 124.5, 123.7,
122.7, 120.6, 48.27, 20.64, 15.7. IR, nmax (CH2Cl2): 3376, 2970, 2849,
1737, 1562, 1518,1348,1211, 1005, 806, 742. Anal. Calcd for C23H20N4
(M¼366.46): C, 78.66; H, 6.05; N, 15.29. Found C, 78.57; H, 5.95; N,
15.21%.
(M¼690.71): C, 60.86; H, 6.13; N, 8.11. Found C, 60.78; H, 6.03; N,
8.01%.
4.3.11. Complex RuL3d. Yield: 0.40 g, 94%. 1H NMR (400 MHz,
CDCl3):
d
10.35 (d, J¼4.7 Hz, 1H, pheneH), 9.84 (d, J¼4.4 Hz, 1H,
pheneH), 9.12 (d, J¼6.9 Hz, 1H, pheneH), 8.76 (d, J¼7.9 Hz, 1H,
pheneH), 8.29 (dd, J¼8.2, 5.2 Hz, 1H, pheneH), 8.09 (s, 1H, C2eH),
8.05 (dd, J¼7.5, 4.2 Hz, 1H, pheneH), 6.47 (d, J¼5.9 Hz, 1H,
4.3.7. Compound L4c. Yield: 2.90 g, 84%. 1H NMR (400 MHz, CDCl3):
d
9.20 (dd, J¼4.4, 1.5 Hz, 1H, pheneH), 9.16 (dd, J¼4.4, 1.8 Hz, 1H,
pheneH), 8.97 (dd, J¼8.1, 1.8 Hz, 1H, pheneH), 8.90 (dd, J¼8.4,
1.6 Hz, 1H, pheneH), 7.74 (m, 2H, pheneH), 7.41 (s, 1H, C2eH), 5.80
(s, 2H, AreCH2), 2.33 (s, 3H, AreCH3), 2.28 (s, 6H, AreCH3), 2.20 (s,
C
10H14(C6H4)), 6.38 (d, J¼6.0 Hz, 1H, C10H14(C6H4)), 6.31 (d,
J¼5.5 Hz, 1H, C10H14(C6H4)), 6.17 (d, J¼5.6 Hz, 1H, C10H14(C6H4)),
4.56 (t, J¼7.3 Hz, 2H, octadecyleCH2), 2.72 (m, 1H,
6H, AreCH3). 13C NMR (100 MHz, CDCl3):
d
149.0, 148.0, 145.1, 144.3,
C10H14(CH(CH3)2)), 2.28 (s, 3H, C10H14(CH3)), 1.87 (m, 2H, octade-
141.2, 137.8, 137.0, 133.8, 133.6, 130.4, 128.7, 126.8, 124.6, 124.5,
123.7, 122.73, 120.65, 48.8, 17.41, 17.08, 16.75. IR, nmax (CH2Cl2):
3376, 2928, 2842, 1738, 1562, 1518, 1349, 1215, 1006, 804, 742. Anal.
Calcd for C25H24N4 (M¼380.48): C, 78.92; H, 6.36; N, 14.73. Found C,
78.84; H, 6.28; N, 14.65%.
cyleCH2), 1.24 (m, 30H, octadecyleCH2), 1.00 (d, J¼6.3 Hz, 6H,
C
10H14(CH(CH3)2)), 0.87 (t, J¼6.8 Hz, 3H, octadecyleCH3). 13C NMR
(100 MHz, CDCl3):
d 155.3, 145.2, 143.9, 137.7, 132.6, 131.2, 127.3,
127.1, 126.1, 124.5, 121.4, 104.9, 104.4, 87.3, 87.2, 84.8, 84.6, 48.4,
32.0, 31.2, 30.0, 29.8, 29.7, 29.6, 29.5, 29.2, 26.7, 22.8, 22.3, 22.2,19.2,
14.2. IR, nmax (CH2Cl2): 2927, 2852, 1740, 1605, 1519, 1452, 1342,
1041, 878, 751. Anal. Calcd for C41H54Cl2N4Ru (M¼774.87): C, 63.55;
H, 7.02; N, 7.23. Found C, 63.46; H, 6.91; N, 7.12%.
4.3.8. Complex RuL3a. Yield: 0.29 g, 91%. 1H NMR (400 MHz,
CDCl3):
d
10.36 (d, J¼5.1 Hz, 1H, pheneH), 9.99 (d, J¼8.0 Hz, 1H,
pheneH), 9.09 (d, J¼7.8 Hz, 1H, pheneH), 8.80 (d, J¼8.3 Hz, 1H,
pheneH), 8.27 (dd, J¼8.2, 5.2 Hz, 1H, pheneH), 8.15 (dd, J¼7.5,
4.5 Hz, 1H, pheneH), 8.11 (s, 1H, C2eH)), 6.47 (d, J¼5.9 Hz, 1H,
4.3.12. Complex RuL4a. Yield: 0.32 g, 89%. 1H NMR (400 MHz,
CDCl3):
d
10.40 (d, J¼8.0 Hz, 1H, pheneH), 10.04 (d, J¼8.2 Hz, 1H,
C
10H14(C6H4)), 6.30 (d, J¼6.0 Hz, 1H, C10H14(C6H4)), 6.33 (d,
pheneH), 9.23 (d, J¼8.0 Hz, 1H, pheneH), 9.11 (d, J¼8.0 Hz, 1H,
pheneH), 8.35 (dd, J¼4.4, 1.5 Hz, 1H, pheneH), 8.10 (dd, J¼4.4,
1.5 Hz, 1H, pheneH), 7.47 (s, 1H, C2eH), 7.01 (s, 2H, AreH), 6.49 (s,
1H, C10H14(C6H4)), 6.35 (d, J¼5.7 Hz, 1H, C10H14(C6H4)), 6.29 (s, 1H,
J¼6.0 Hz, 1H, C10H14(C6H4)), 6.22 (d, J¼6.0 Hz, 1H, C10H14(C6H4)),
4.57 (t, J¼7.3 Hz, 2H, butyleCH2), 2.71 (m, 1H, C10H14(CH(CH3)2)),
2.28 (s, 3H, C10H14(CH3)), 1.99 (m, 2H, butyleCH2), 1.43 (m, 2H,
butyleCH2), 0.99 (m, 9H, butyleCH3, C10H14(CH(CH3)2). 13C NMR
C10H14(C6H4)), 6.24 (s, 1H, C10H14(C6H4)), 5.77 (m, 2H, AreCH2), 2.72
(100 MHz, CDCl3):
d
155.0, 147.0, 143.8, 137.3, 132.8, 127.3, 126.8,
(m, 1H, C10H14(CH(CH3)2)), 2.36 (s, 3H, AreCH3), 2.28 (s, 3H,
125.9, 124.6, 121.5, 104.7, 103.8, 87.1, 87.0, 86.1, 84.8, 84.6, 47.4, 32.0,
31.0, 22.3, 22.1, 19.7, 18.9, 14.1. IR, nmax (CH2Cl2): 2961, 2924, 1714,
C
C
10H14(CH3)), 2.24 (s, 6H, AreCH3), 0.99 (d, J¼6.9 Hz, 6H,
10H14(CH(CH3)2)). 13C NMR (100 MHz, CDCl3):
d
155.4, 144.0, 143.9,

€ €
L. Gok, H. Turkmen / Tetrahedron 69 (2013) 10669e10674
10674
142.6, 139.9, 138.2, 137.9, 132.6, 132.1, 130.1, 127.3, 127.1, 126.1, 125.8,
125.5, 121.9, 104.7, 104.5, 87.5, 87.3, 84.6, 47.8, 31.2, 22.4, 22.3, 21.3,
19.7,19.3. IR, nmax (CH2Cl2): 2965, 2854,1602,1521,1450,1360,1212,
1032, 874, 724. Anal. Calcd for C33H30Cl2N4Ru (M¼654.59): C, 60.55;
H, 4.62; N, 8.56. Found C, 60.44; H, 4.58; N, 8.47%.
(M¼802.97): C, 52.35; H, 7.28; N, 6.98. Found C, 52.27; H, 713; N,
6.72%.
4.4. General procedure for the transfer hydrogenation
reaction
4.3.13. Complex RuL4b. Yield: 0.33 g, 90%. 1H NMR (400 MHz,
The tested complex (0.01 mmol; 1 mol %) was dissolved in
a solution of KOH (0.1 mmol) and 2-propanol (5 ml) in a two necked
flask. The solution was heated to 82 ꢁC for 30 min. Subsequently,
acetophenone (1 mmol) was added. After the desired reaction time
the solution was allowed to cool and quenched with 1 M HCl,
extracted with CH2Cl2 and the organic phase separated. The re-
action progress was monitored by 1H NMR and GC the results for
each experiment are averages over two runs.
CDCl3):
d
10.42 (d, J¼5.2 Hz, 1H, pheneH), 9.90 (d, J¼4.6 Hz, 1H,
pheneH), 9.19 (d, J¼8.4 Hz, 1H, pheneH), 9.13 (d, J¼8.2 Hz, 1H,
pheneH), 8.33 (dd, J¼4.4, 1.5 Hz, 1H, pheneH), 8.05 (dd, J¼4.4,
1.5 Hz, 1H, pheneH), 7.48 (s, 1H, C2eH), 7.14 (s, 1H, AreH), 6.53 (d,
J¼5.2 Hz, 1H, C10H14(C6H4)), 6.29 (d, J¼6.2 Hz, 2H, C10H14(C6H4)),
6.20 (d, J¼6.2 Hz, 1H, C10H14(C6H4)), 6.24 (s, 1H, C10H14(C6H4)), 5.83
(m, 2H, AreCH2), 2.73 (m, 1H, C10H14(CH(CH3)2)), 2.30 (s, 6H,
AreCH3), 2.29 (s, 3H, C10H14(CH3)), 2.15 (s, 6H, AreCH3), 0.99 (d,
J¼6.9 Hz, 6H, C10H14(CH(CH3)2)). 13C NMR (100 MHz, CDCl3):
Acknowledgements
d
155.2, 144.0, 143.1, 137.9, 137.8, 135.1, 134.1, 133.5, 132.6, 131.8,
128.6, 127.0, 126.1, 125.3, 121.9, 104.7, 104.5, 87.4, 87.2, 84.6, 84.5,
48.5, 31.2, 22.4, 22.3, 20.6, 19.2. IR, nmax (CH2Cl2): 2965, 2857, 1601,
1450, 1404, 1359, 1210, 1005, 874, 724. Anal. Calcd for
_
Financial support was from Ege University (Project 2012-BIL-
042) and TUBITAK (111T398). We thank to Prof. Dr. S. Astley at Ege
University Chemistry Department for reading the manuscript and
C
34H32Cl2N4Ru (M¼668.62): C, 61.08; H, 4.82; N, 8.38. Found C,
€
Mr. Salih Gunnaz for NMR analyses.
61.01; H, 4.75; N, 8.26%.
4.3.14. Complex RuL4c. Yield: 0.34 g, 91%. 1H NMR (400 MHz,
Supplementary data
CDCl3):
d
10.33 (d, J¼5.2 Hz, 1H, pheneH), 9.91 (d, J¼4.9 Hz, 1H,
pheneH), 9.16 (d, J¼8.1 Hz, 1H, pheneH), 9.12 (d, J¼8.1 Hz, 1H,
pheneH), 8.28 (dd, J¼8.2, 5.2 Hz, 1H, pheneH), 8.05 (dd, J¼8.1,
5.2 Hz, 1H, pheneH), 7.52 (s, 1H, C2eH), 6.47 (d, J¼5.8 Hz, 1H,
Supplementary data associated with this article can be found in
the online version, at http://dx.doi.org/10.1016/j.tet.2013.09.023.
These data include MOL files and InChiKeys of the most important
compounds described in this article.
C
10H14(C6H4)), 6.28 (d, J¼5.7 Hz, 1H, C10H14(C6H4)), 6.25 (d,
J¼5.8 Hz, 1H, C10H14(C6H4)), 6.17 (d, J¼6.0 Hz, 1H, C10H14(C6H4)),
5.82 (m, 2H, AreCH2), 2.71 (m, 1H, C10H14(CH(CH3)2)), 2.33 (s, 3H,
References and notes
C
10H14(CH3)), 2.28 (s, 6H, AreCH3), 2.26 (s, 3H, AreCH3), 2.19 (s, 6H,
AreCH3), 0.99 (d, J¼6.9 Hz, 6H, C10H14(CH(CH3)2)). 13C NMR
1. Kazushi, M.; Koh-hei, K.; Naomasa, S.; Yoh-ichi, M.; Kyoko, N.; Hidenori, K.;
Noboru, S.; Yoji, H.; Takero, I. J. Org. Chem. 1994, 59, 3064.
(100 MHz, CDCl3):
d 155.3, 144.0, 143.9, 143.2, 138.0, 137.3, 134.0,
133.6, 132.7, 131.7, 127.2, 127.0, 126.2, 125.9, 125.3, 122.0, 104.8,
104.4, 87.4, 87.3, 84.7, 84.5, 49.0, 31.2, 22.4, 22.3, 19.2, 17.4, 17.0, 16.8.
IR, nmax (CH2Cl2): 2965, 2854, 1602, 1521, 1450, 1360, 1212, 1030,
811, 724. Anal. Calcd for C35H34Cl2N4Ru (M¼682.65): C, 61.58; H,
5.02; N, 8.21. Found C, 61.51; H, 4.84; N, 8.03%.
2. Shohei, H.; Akio, F.; Jun, T.; Takao, I.; Ryoj, N. J. Am. Chem. Soc. 1995, 117, 7562.
3. Katho, A.; Carmona, D.; Viguri, F.; Remacha, C. D.; Kovacs, J.; Joo, F.; Oro, L. A. J.
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5. De Clercq, B.; Verpoort, F. J. Mol. Catal. A: Chem. 2002, 180, 67.
6. Sterk, D.; Stephanb, M. S.; Mohara, B. Tetrahedron: Asymmetry 2002, 13, 2605.
€
7. Canivet, J.; Karmazin-Brelot, L.; Suss-Fink, G. J. Organomet. Chem. 2005, 690,
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4.3.15. Complex RuL3d . Yield: 0.37 g, 91%. 1H NMR (400 MHz,
0
8. Stumpf, A. W.; Saive, E.; Demonceau, A.; Noels, A. F. J. Chem. Soc., Chem. Com-
mun. 1995, 1127.
9. Tse, M. K.; Jiao, H.; Anilkumar, G.; Bitterlich, B.; Gelalcha, F. G.; Beller, M. J.
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Angew. Chem., Int. Ed. 2004, 43, 5255.
11. Yan, Y. K.; Melchart, M.; Habtemariam, A.; Sadler, P. J. Chem. Commun. 2005,
CDCl3):
d
9.32 (d, J¼5.2 Hz, 1H, pheneH), 9.18 (d, J¼4.8 Hz, 1H,
pheneH), 9.09 (d, J¼8.0 Hz, 2H, pheneH), 8.53 (dd, J¼7.6, 5.6 Hz,
1H, pheneH), 8.12 (m, 1H, J¼6.0, 5.2 Hz, pheneH, s, 1H, C2eH), 4.80
(t, J¼7.4 Hz, 2H, octadecyleCH2), 2.14 (s, 18H, C12H18(CH3)), 1.98 (m,
2H, octadecyleCH2),1.24 (m, 30H, octadecyleCH2), 0.87 (t, J¼6.8 Hz,
€
4764.
3H, octadecyleCH3). 13C NMR (100 MHz, CDCl3):
d 154.2, 146.5,
12. Ang, W. H.; Dyson, P. J. Eur. J. Inorg. Chem. 2006, 20, 4003.
13. Koelle, U. Coord. Chem. Rev. 1994, 135/136, 623.
14. Herrmann, W. A.; Kohlpaintner, W. C. Angew. Chem. 1993, 105, 1588.
144.1, 140.8, 137.8, 137.5, 137.2, 134.3, 132.2, 130.0, 129.5, 128.5,
128.2, 123.3, 47.4, 32.0, 29.8, 29.7, 29.6, 29.5, 29.3, 29.0, 22.8, 22.6,
22.5, 17.2, 14.2. IR, nmax (CH2Cl2): 2923, 2852, 1601, 1526, 1451, 1400,
1303,1215,1015, 726. Anal. Calcd for C43H62C12N4Ru (M¼806.96): C,
64.00; H, 7.74; N, 6.94. Found C, 63.52; H, 7.11; N, 6.73%.
15. Samuelson, A. G. Curr. Sci. 1992, 63, 547.
16. Pike, R. D.; Sweigart, D. A. Coord. Chem. Rev. 1999, 187, 183.
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2201; (b) Gladiali, S.; Alberico, E. Chem. Soc. Rev. 2006, 35, 226; (c) Turkmen, H.;
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€
4.3.16. Complex RuL3d . Yield: 0.41 g, 93%. 1H NMR (400 MHz,
_
00
DMSO):
d
9.48 (d, J¼5.2 Hz, 1H, pheneH), 9.22 (d, J¼4.8 Hz, 1H,
1998, 63, 2749.
pheneH), 9.16 (d, J¼8.0 Hz, 2H, pheneH), 8.61 (dd, J¼7.6, 5.6 Hz,1H,
pheneH), 8.17 (m, 1H, J¼6.0, 5.2 Hz, pheneH, s, 1H, C2eH), 4.42
(t, J¼7.4 Hz, 2H, octadecyleCH2), 2.50 (s, 12H, DMSO(CH3)), 2.14
(s, 18H, C12H18(CH3)) 1.97 (m, 2H, octadecyleCH2), 1.24 (m, 30H,
octadecyleCH2), 0.87 (t, J¼6.8 Hz, 3H, octadecyleCH3). 13C NMR
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(100 MHz, DMSO):
d 156.3, 146.0, 145.0, 142.6, 136.0, 132.3, 132.0,
131.8,131.6,130.3,126.5,125.2, 48.6, 32.0, 29.7, 29.5, 29.3, 28.8, 28.6,
26.5, 22.4, 14.2. IR, nmax (CH2Cl2): 2922, 2852, 1601, 1524, 1402,
1309, 1212, 1097, 1019, 723. Anal. Calcd for C35H58Cl2N4O2RuS2