Synthesis and reaction of ruthenium(II) complexes containing heteroatom donor (O, N, and P) tethered to η6-arene ring

Article abstract of DOI:10.1016/S0020-1693(99)00538-1

Synthesis of ruthenium(II) complexes chelated by the η⁶-arene ring and a pendent donor atom (O, N, and P) is described. The alcohol-containing η⁶-arene ruthenium complexes [Ru{η⁶-C₆H₅(CH₂)₃OH}(PR₃)Cl₂] (1a R=Ph; lb R = Et) and [Ru{η⁶C₆H₅(CH₂)₃OH}L₂Cl]BF₄ (2a L₂2,2'-bipyridine; 2b L2= 1,10-phenanthroline; 2c L₂2,2-bis[4(R)-phenyl-1,3-oxazolon-2-yl]propane, (R)-bpop) were prepared by treatment of [Ru{η⁶-C₆H₅(CH₂)₃OH}Cl₂]₂ with tertiary phosphines or N,N'-chelate ligands/NaBF₄, respectively. Addition of 1 equiv. of AgBF₄ to a solution of complexes 1 or 2 gave alcohol chelate complexes [Ru{η⁶:η¹-C₆H₅(CH₂)₃OH}(PR₃)Cl]BF₄ (3a-b) or [Ru{η⁶:η¹-C6H₅(CH₂)₃OH}L₂](BF₄)₂ (4a-c), respectively. Although stable in MeOH, the alcohol-Ru chelate bond of 3 and 4 was cleaved by Cl(min) ion. Treatment of 4 with bases (OH(min), R₃N) led to abstraction of the hydroxy proton to give alkoxy chelate complexes [Ru{η⁶:η¹-C₆H₅(CH₂)₃O}L₂]BF₄ (5a-c). In CH₂Cl₂ acidity of the hydroxy proton in 4c was revealed to be comparable to that of N-methylbenzylammonium cation (pK(a) in H₂O, ca. 11). Amino chelate complexes [Ru{η⁶:η¹-C₆H₅(CH₂)(n)NH₂}(PPh₃)Cl]BF₄ (Tan = 3; 7b n = 2) were prepared by treatment of ammonium complexes [Ru{η⁶-C₆H₅(CH₂)(n)NH₃Cl}(PPh₃)Cl₂] (6a n = 3; 6b n = 2) with 1 equiv. of NaOH and NaBF₄. 7 were stable to the attack of Cl(min) ion. In contrast, the similar treatment of dimethylammonium derivative [Ru{η⁶-C₆H₅(CH₂)₃NMe₂HCl}(PPh₃)Cl₂] (8) with KOH gave a non-chelate complex [Ru{η⁶-C₆H₅(CH₂)₃NMe₂}(PPh₃)Cl₂] (9). Phosphorous chelate complexes [Ru{η⁶:η¹-C₆H₅(CH₂)₃OPPR₂}Cl₂] (10a R=Ph; 10b R=(i)Pr) were prepared by reaction of [Ru{η⁶C₆H₅(CH₂)₃OH}Cl₂]₂, PPR₂Cl, and EtN(i)Pr₂. Treatment of 10b with AgBF₄ and CO (1 atm) gave the cationic carbonyl complex [Ru{η⁶:η¹-C₆H₅(CH₂)₃OP(i)Pr²}(CO)Cl]BF₄ (11). (C) 2000 Elsevier Science S.A.

Full text of DOI:10.1016/S0020-1693(99)00538-1

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Inorganica Chimica Acta 300–302 (2000) 369–377
Synthesis and reaction of ruthenium(II) complexes containing
heteroatom donor (O, N, and P) tethered to h6-arene ring
Yoshiharu Miyaki, Takafumi Onishi, Hideo Kurosawa *
Department of Applied Chemistry, Faculty of Engineering, Osaka Uni6ersity, Suita, Osaka 565-0871, Japan
Received 13 September 1999; accepted 4 November 1999
Abstract
Synthesis of ruthenium(II) complexes chelated by the h6-arene ring and a pendent donor atom (O, N, and P) is described. The
alcohol-containing h6-arene ruthenium complexes [Ru{h6-C6H5(CH2)3OH}(PR3)Cl2] (1a R=Ph; 1b R=Et) and [Ru{h6-
C6H5(CH2)3OH}L2Cl]BF4 (2a L2=2,2%-bipyridine; 2b L2=1,10-phenanthroline; 2c L2=2,2-bis[4(R)-phenyl-1,3-oxazolon-2-
yl]propane, (R)-bpop) were prepared by treatment of [Ru{h6-C6H5(CH2)3OH}Cl2]2 with tertiary phosphines or N,N%-chelate
ligands/NaBF4, respectively. Addition of 1 equiv. of AgBF4 to a solution of complexes 1 or 2 gave alcohol chelate complexes
[Ru{h6:h1-C6H5(CH2)3OH}(PR3)Cl]BF4 (3a–b) or [Ru{h6:h1-C6H5(CH2)3OH}L2](BF4)2 (4a–c), respectively. Although stable in
MeOH, the alcoholꢀRu chelate bond of 3 and 4 was cleaved by Cl− ion. Treatment of 4 with bases (OH−, R3N) led to
abstraction of the hydroxy proton to give alkoxy chelate complexes [Ru{h6:h1-C6H5(CH2)3O}L2]BF4 (5a–c). In CH2Cl2 acidity
of the hydroxy proton in 4c was revealed to be comparable to that of N-methylbenzylammonium cation (pKa in H2O, ca. 11).
Amino chelate complexes [Ru{h6:h1-C6H5(CH2)nNH2}(PPh3)Cl]BF4 (7a n=3; 7b n=2) were prepared by treatment of ammo-
nium complexes [Ru{h6-C6H5(CH2)nNH3Cl}(PPh3)Cl2] (6a n=3; 6b n=2) with 1 equiv. of NaOH and NaBF4. 7 were stable to
the attack of Cl− ion. In contrast, the similar treatment of dimethylammonium derivative [Ru{h6-C6H5(CH2)3NMe2-
HCl}(PPh3)Cl2] (8) with KOH gave a non-chelate complex [Ru{h6-C6H5(CH2)3NMe2}(PPh3)Cl2] (9). Phosphorous chelate
complexes [Ru{h6:h1-C6H5(CH2)3OPPR2}Cl2] (10a R=Ph; 10b R=iPr) were prepared by reaction of [Ru{h6-
C6H5(CH2)3OH}Cl2]2, PPR2Cl, and EtNiPr2. Treatment of 10b with AgBF4 and CO (1 atm) gave the cationic carbonyl complex
[Ru{h6:h1-C6H5(CH2)3OPiPr2}(CO)Cl]BF4 (11). © 2000 Elsevier Science S.A. All rights reserved.
Keywords: Arene complexes; Ruthenium complexes; Heteroatom donor complexes; Crystal structure
1. Introduction
ands and the synthesis of modified h6-arene ligands
seemed to be easier than that of the modified cyclo-
pentadienyl ligands, transition metal complexes with a
coordination group tethered to the h6-arene ligand
have received much less attention [5]. Here we report
the synthesis of ruthenium(II) complexes chelated by
alcohol, amine, or phosphite donor and h6-arene lig-
and. In spite of the key role as intermediates in homo-
geneous catalytic [6a,b] as well as biochemical
transformations [6c–e], late transition metal alcohol
complexes have rarely been subjects of molecular level
coordination chemistry because of the weak MꢀO
bond. Studies of the synthesis and properties of mod-
erately stable alcohol complexes are thus of potential
interest to development of some catalytic processes.
Part of the present work has been published in a
preliminary communication [7].
In recent years, the coordination chemistry of
chelated ligands containing mixed functionalities on
transition metal centers has been an extremely active
area of research [1]. In particular, transition metal
complexes with a coordination group which is tethered
to the cyclopentadienyl ligand have attracted attention
from viewpoints of improving and elucidating catalytic
processes such as olefin polymerization [2–4]. Nitro-
gen [2], oxygen [3], and phosphorous [4] have been
used as the coordination atom. Although h6-arene lig-
ands are isoelectronic with the h5-cyclopentadienyl lig-
* Corresponding author. Tel.: +81-6-6879 7392; fax: +81-6-6879
7394.
0020-1693/00/$ - see front matter © 2000 Elsevier Science S.A. All rights reserved.
PII: S0020-1693(99)00538-1

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Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
Scheme 1.
2. Results and discussion
larly to 2c starting from C6H7(CH2)2OH, did not afford
the corresponding alcohol chelate complex, as suggested
by the appearance of only a single OCH2 resonance.
1H NMR spectra of 4c measured in CD3OD were
almost the same as those in CDCl3 or CD2Cl2, suggesting
that coordination of the pendent alcohol is maintained
even in MeOH. The analogous coordination of the
(CH2)3OH group of 4a and 4b in CD3OD was also
2.1. Synthesis and structures of alcohol chelate
complexes
Cyclohexadiene derivatives with a terminal alcohol
functionality C6H7(CH2)nOH (n=2, 3) were prepared
by Birch reduction [8] of commercially available
C6H5(CH2)nOH. Treatment of RuCl3 with C6H7(CH2)3-
OH (5 equiv.) in refluxing ethanol gave orange solids of
h6-arene ruthenium dichloride [Ru{h6-C6H5(CH2)3-
OH}Cl2] in high yield. This was converted to the
monomeric neutral phosphine complexes 1a–b or the
cationic complexes containing N,N%-chelate 2a–c when
treated with the tertiary phosphines or the N,N%-donor
and NaBF4, respectively (Scheme 1). The solid state
structure of 2a is shown in Fig. 1 (Table 1). Reaction of
1 or 2 with AgBF4 (1 equiv.) in CH2Cl2 and methanol
at r.t. gave the cationic complexes 3a–b or dicationic
complexes 4a–c, respectively (Scheme 1). The chelate
coordination of the alcohol ligand in 4b and 4c was
confirmed by X-ray crystallography (Figs. 2 and 3;
Tables 2 and 3). The 1H NMR data of 3 and 4c in CDCl3
or CD2Cl2 at r.t. showing two diastereotopic OCH2
resonances of the alcohol group1 were diagnostic for the
coordination of alcohol ligand in solution, while only a
single OCH2 resonance was observed in 1 and 2. Reaction
of AgBF4 with the shorter side-arm analog [Ru{h6-C6H5-
(CH2)2OH}(bpop)Cl]BF4 (bpop=2,2-bis[4(R)-phenyl-
1,3-oxazolon-2-yl]propane), which was obtained simi-
1 The chemical shifts of OCH2 protons in 3 and 4c are as follows
(see Section 3). 3a: l 3.44, 3.78; 3b: l 3.48, 3.92; 4c: l 2.18, 3.55.
Fig. 1. ORTEP drawing of 2a. BF4 was omitted for clarity. Thermal
ellipsoids are drawn at the 50% probability level.

Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
371
1
Table 1
Selected bond distance (A) and angle (°) of 2a
assessed by H NMR spectra. Thus, the proton reso-
nances of this group in freely rotating CꢀC bond in 2a
and 2b appeared as a typical A2M2X2 spin system,
while those in 4a and 4b appeared as more complex
AA%MM%XX% patterns since the free rotation about the
,
Ru(1)ꢀCl(1)
Ru(l)ꢀN(1)
Ru(1)ꢀN(2)
Ru(1)ꢀC(1)
Ru(1)ꢀC(2)
Ru(1)ꢀC(3)
Ru(1)ꢀC(4)
Ru(1)ꢀC(5)
Ru(1)ꢀC(6)
2.397(1)
2.077(4)
2.080(4)
2.188(5)
2.158(5)
2.158(5)
2.196(5)
2.192(5)
2.211(5)
1
CꢀC axis is restricted. H NMR spectra of 3 measured
in CD3OD were too complex to allow any structure
assessment.
The alcohol chelate complexes 3 and 4 readily re-
acted with 1 equiv. of [PPh4]Cl to give the original
chloride complexes 1 and 2 in almost quantitative
yields. Of particular note was the reaction of 4 with
NaOH in MeOH affording alkoxide complexes 5
(Scheme 2). No b-hydrogen elimination giving aldehyde
functionalities has been observed in 5, presumably ow-
ing to difficulty for the RuꢀOꢀCꢀH framework to lie in
a plane. The solid state structure of 5a is shown in Fig.
4 (Table 4). Significantly, the bond distance of RuꢀO in
5a was shorter than that of RuꢀO in 4b by approxi-
Cl(1)ꢀRu(1)ꢀN(1)
Cl(1)ꢀRu(1)ꢀN(2)
N(1)ꢀRu(1)ꢀN(2)
85.2(1)
84.5(1)
76.9(1)
,
mately 0.1 A. There was no difference of the bond
angles around the Ru center and the distance between
Ru and the arene ring. One molecule of MeOH is
contained in the unit cell. The distance between the
oxygen of methanol and the Ru-bound alkoxo oxygen
Table 2
,
Selected bond distance (A) and angle (°) of 4b
Ru(1)ꢀO(1)
Ru(1)ꢀN(1)
Ru(1)ꢀN(2)
Ru(1)ꢀC(4)
Ru(1)ꢀC(5)
Ru(1)ꢀC(6)
Ru(1)ꢀC(7)
Ru(1)ꢀC(8)
Ru(1)ꢀC(9)
2.145(3)
2.096(3)
2.096(3)
2.204(4)
2.196(4)
2.165(4)
2.163(5)
2.168(4)
2.189(4)
Fig. 2. ORTEP drawing of 4b. BF4 was omitted for clarity. Thermal
ellipsoids are drawn at the 50% probability level.
O(1)ꢀRu(1)ꢀN(1)
O(1)ꢀRu(1)ꢀN(2)
N(1)ꢀRu(1)ꢀN(2)
81.0(1)
83.2(1)
77.9(1)
Table 3
,
Selected bond distance (A) and angle (°) of 4c
Ru(1)ꢀO(3)
Ru(1)ꢀN(1)
Ru(1)ꢀN(2)
Ru(1)ꢀC(40)
Ru(1)ꢀC(41)
Ru(1)ꢀC(42)
Ru(1)ꢀC(43)
Ru(1)ꢀC(44)
Ru(1)ꢀC(45)
2.11(2)
2.10(2)
2.14(2)
2.24(3)
2.13(3)
2.20(2)
2.18(3)
2.11(4)
2.13(5)
O(3)ꢀRu(1)ꢀN(1)
O(3)ꢀRu(1)ꢀN(2)
N(1)ꢀRu(1)ꢀN(2)
85.2(8)
81.6(8)
82.0(8)
Fig. 3. ORTEP drawing of 4c. BF4 and H2O were omitted for clarity.
Thermal ellipsoids are drawn at the 50% probability level.

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Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
Table 4
,
Selected bond distance (A) and angle (°) of 5a
Ru(1)ꢀO(1)
Ru(1)ꢀN(1)
Ru(1)ꢀN(2)
Ru(1)ꢀC(1)
Ru(1)ꢀC(9)
Ru(1)ꢀC(2)
Ru(1)ꢀC(4)
Ru(1)ꢀC(19)
Ru(1)ꢀC(18)
O(1)ꢀRu(1)ꢀN(1)
O(1)ꢀRu(l)ꢀN(2)
N(1)ꢀRu(1)ꢀN(2)
2.050(5)
2.064(6)
2.107(6)
2.203(8)
2.178(7)
2.179(7)
2.205(7)
2.191(8)
2.185(9)
82.5(2)
80.9(2)
77.6(3)
Scheme 2.
,
iis 2.67 A, suggesting the existence of the hydrogen
bond with regard to these oxygen atoms.
3). The two methylene protons geminal to N in 7
were observed non-equivalent. Unlike the failure of
the CH2CH2OH side-arm to form a stable chelate
structure (see above), 7b with the side-arm of the
similar length was stable enough to maintain the co-
ordination of the amine nitrogen.
2.2. Synthesis of amine chelate complexes
Cyclohexadiene derivatives with nitrogen donor
atom were prepared by Birch reduction. However, the
reaction of these cyclohexadienes with RuCl3, a com-
mon method of preparing arene ruthenium dimer
complexes, did not work well. So, the cyclohexadienes
with amine were first treated with hydrochloric acid
to give the ammonium salts, which were subsequently
treated with RuCl3 to give the h6-arene dimer com-
plexes containing the ammonium side-chain (Scheme
3). Then these were treated with triphenylphosphine
in refluxing MeCN for 2 h to give monomeric com-
plexes 6, which gave amino chelate complexes 7 upon
treatment with sodium hydroxide and NaBF4 (Scheme
Treatment of a dimethylamino derivative 8, synthe-
sized similarly to 6, with KOH gave a non-chelate
1
complex 9 (Scheme 4). In the H NMR spectra of 9
the resonance of the methylene protons geminal to N
and the N-methyl resonance appeared as a triplet and
a singlet, respectively. This result is in sharp contrast
to the reaction of 6a with sodium hydroxide in the
absence of NaBF4 which gave a chelate complex hav-
ing a chloride counter ion. Moreover, 7 were stable
to the attack of Cl− ion. These results suggest a
stronger coordination power of NH2 than NMe2.
Scheme 3.
Fig. 4. ORTEP drawing of 5a. BF4 and MeOH were omitted for
clarity. Thermal ellipsoids are drawn at the 50% probability level.
Scheme 4.

Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
373
2.3. Synthesis of phosphite chelate complexes
Treatmentof[Ru{h6-C6H5(CH2)3OH}Cl2]2withchloro-
phosphine ClPR2 and EtNiPr2 gave neutral phos-
phorous chelate complexes 10a and 10b (Scheme 5). The
use of K2CO3, KOH, and pyridine as bases did not
afford 10.
Treatment of the phosphorous chelate complex 10b
with AgPF6 and CO gas (1 atm) in CH2Cl2 gave
carbonyl complex 11 in high yield (Scheme 6). This is
shown clearly by the infrared spectrum, where only a
single carbonyl stretching band at 2035 cm−1 was
observed. Mono-substituted arene ruthenium carbonyl
complex has to our knowledge not ever been reported.
In CH2Cl2 solution under inert atmosphere 11 was labile
to lead to decomposition.
Fig. 5. Variation of chemical shift of meta-H in h6-C6H5R ring as a
function of equivalent of amine added to 4c; triethylamine (ꢀ),
benzylmethylamine (×), and dibenzylamine (ꢁ).
2.4. Acidity of hydroxy proton in 4c
Addition of amine to a CD2Cl2 solution of 4c resulted
in the formation of an equilibrium mixture of 4c and 5c,
the ratio of the two species being dependent on the
amount and basicity of the amine. The rate of intercon-
version between 4c and 5c was confirmed rapid on the
NMR time scale; averaging was observed at 25°C for
each pair of resonances due to protons of 4c and the
corresponding protons of 5c. Among these, the aver-
aged position of one of the meta-H in h6-C6H5R ring
moved from l 6.80 in 4c to l 5.85 in 5c, when 4c was
titrated with an amine (Fig. 5). This allowed us to assess
acid–base equilibrium constants expressed by Eq. (1); a
least-squares curve-fitting afforded Keq=1.0290.13 for
B=(C6H5CH2)(CH3)NH and 0.4390.08 for B=
(C6H5CH2)2NH, suggesting that in CH2Cl2 the acidity
of the coordinating alcohol in 4c is comparable to
those of ammonium salts formed from these amines
(pKa in H2O, ca. 11). Triethylamine was too basic to
allow correct estimation of the equilibrium constant.
(1)
2.5. Conclusion
The chelate effect exerted by the h6-arene ligand and
the pendent donor atom was shown useful to stabilize
otherwise labile binding of some ligands such as alco-
hols to a ruthenium center. The present effort may also
become suitable for looking into details of coordination
behavior of the synthetically important donor groups
such as alcohols, alkoxides, amines, and amides in a
systematic manner.
3. Experimental
General remarks. Most of the commercially available
reagents were used without further purification. Sol-
vents were dried by standard methods and distilled prior
Scheme 5.
1
to use. H and 31P NMR spectra were recorded with
JEOL GSX-270 and GSX-400 spectrometers.
3.1. Preparation of complexes
3.1.1. [Ru{p6-C6H5(CH2)3OH}Cl2]2
To a solution of hydrated ruthenium trichloride (1.28
g, 5.1 mmol) in ethanol (62 ml) was added C6H7(CH2)3-
Scheme 6.

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Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
OH (3.5 g, 25 mmol) and the mixture was refluxed for
4 h. The orange precipitate was filtered off, washed
with ether, and dried in vacuo to give the chloride
Hz, 2H), 9.84 (dd, J=5.3, 0.95 Hz, 2H). Anal. Calc. for
C21H20BClF4N2ORu: C, 46.73; H, 3.73; N, 5.19.
Found: C, 46.48; H, 3.57; N, 5.21.
1
dimer (1.42 g, 90%). H NMR (CD3CN): l 1.83 (tt,
3.1.6. [Ru{p6-C6H5(CH2)3OH}(bpop)Cl]BF4 (2c)
J=6.2, 7.7 Hz, 2H), 2.61 (t, J=7.7 Hz, 2H), 3.58 (brs,
2H), 5.46 (d, J=5.9 Hz, 2H), 5.61 (t, J=5.5 Hz, 1H),
5.70 (t, J=5.9 Hz, 2H). Anal. Calc. for C18H24-
Cl4O2Ru2: C, 35.08; H, 3.92. Found: C, 35.31; H, 3.77.
This was prepared in MeOH (80 ml) using [Ru{h6-
C6H5(CH2)3OH}Cl2]2 and (R)-bpop. After stirring for
5.5 h, the mixture was poured into a separatory funnel
containing CH2Cl2 and water. The crude product ob-
tained by separation and evaporation of CH2Cl2 was
purified by column chromatography (Wako C-200 silica
gel, ether and CH3CO2Et/CH2Cl2 (3/2)) to give 559 mg
3.1.2. [Ru{p6-C6H5(CH2)3OH}(PPh3)Cl2] (1a)
To a suspension of [Ru{h6-C6H5(CH2)3OH}Cl2]2
(1.03 g, 3.33 mmol/Ru) in acetonitrile (50 ml) was
added triphenylphosphine (873 mg, 3.33 mmol) and the
mixture was stirred for 14 h at r.t. to give an orange
suspension. The suspension was filtered off to give
orange powders 1a (1.07 g). The filtrate was evaporated
and recrystallization from CH2Cl2/n-hexane gave or-
ange–red crystalline 1a (516 mg). Total 1.58 g (83%).
1H NMR (CDCl3): l 1.98 (m, 2H), 2.81 (t, J=5.0 Hz,
2H), 3.80 (brt, J=5.4 Hz, 2H), 4.54 (brt, J=4.5 Hz,
1H), 5.14 (t, J=4.6 Hz, 2H), 5.37 (d, J=5.9 Hz, 2H),
7.30–7.77 (m, 15H). 31P NMR (CDCl3): l 28.80 (s).
Anal. Calc. for C27H27Cl2OPRu: C, 56.85; H, 4.77.
Found: C, 56.67; H, 4.70.
1
(62%) of orange solids 2c. H NMR (CDCl3): l 1.45
(m, 1H), 1.58 (m, 1H), 1.73 (s, 3H), 1.76 (m, 1H), 1.82
(s, 3H), 2.33 (m, 1H), 3.50 (brt, J=6.1 Hz, 2H), 4.27
(dd, J=6.8, 8.4 Hz, 1H), 4.41 (dd, J=4.6, 8.6 Hz, 1H),
4.76–4.85 (m, 3H), 4.99 (d, J=6.5 Hz, 1H), 5.24 (dd,
J=8.4, 10.5 Hz, 1H), 5.36 (dd, J=5.7, 5.9 Hz, 1H),
5.54 (dd, J=4.6, 10.0 Hz, 1H), 6.02 (dd, J=5.4, 5.7
Hz, 1H), 6.14 (dd, J=6.8, 10.5 Hz, 1H), 7.38–7.64 (m,
10H). Anal. Calc. for C30H34BClF4N2O3Ru·0.5H2O: C,
51.26; H, 5.02; N, 3.99. Found: C, 51.18; H, 4.94; N,
3.98.
3.1.7. [Ru{p6:p1-C6H5(CH2)3OH}(PPh3)Cl]BF4 (3a)
To a solution of 1a (1.42 g, 2.49 mmol) in CH2Cl2
(50 ml) was added a solution of AgBF4 (485 mg, 2.49
mmol) in MeOH (3 ml) and the mixture was stirred for
15 min. The suspension was filtered and the solvent was
evaporated. Recrystallization from MeOH gave 1.34 g
(82%) of an orange crystalline product. 1H NMR
(CD2Cl2): l 2.22 (m, 2H), 2.73 (m, 2H), 3.44 (m, 1H),
3.78 (m, 1H), 4.38 (t, J=5.1 Hz, 1H), 4.79 (m, 1H),
5.04 (t, J=4.9 Hz, 1H), 5.37 (m, 1H), 6.01 (t, J=4.9
Hz, 1H), 6.31 (d, J=5.9 Hz, 1H), 7.47–7.56 (m, 15H).
31P NMR (CD2Cl2): l 33.69 (s). Anal. Calc. for
C27H27BClF4NOPRu·CH3OH: C, 51.43; H, 4.78.
Found: C, 51.12; H, 4.89.
3.1.3. [Ru{p6-C6H5(CH2)3OH}(PEt3)Cl2] (1b)
This was prepared similarly to 1a (84%). H NMR
(CDCl3): l 1.14 (dt, J=15.1, 7.8 Hz, 9H), 1.96–2.12
(m, 8H), 2.76 (t, J=7.3 Hz, 2H), 3.83 (t, J=5.9 Hz,
2H), 5.13 (m, 1H), 5.44 (s, 4H). 31P NMR (CDCl3): l
28.57 (s). Anal. Calc. for C15H27Cl2OPRu: C, 42.26; H,
6.38. Found: C, 42.10; H, 6.19.
1
3.1.4. [Ru{p6-C6H5(CH2)3OH}(bipy)Cl]BF4 (2a)
To a suspension of [Ru{h6-C6H5(CH2)3OH}Cl2]2
(500 mg, 1.62 mmol/Ru) in acetonitrile (60 ml) was
added 2,2%-bipyridine (253 mg, 1.62 mmol) and the
mixture was stirred for 2 h at r.t., followed by addition
of NaBF4 (178 mg, 1.62 mmol). After stirring for
further 14 h, the mixture was filtered and the solvent
was evaporated. The residue was recrystallized from
MeCN/ether to give an orange crystalline product (629
3.1.8. [Ru {p6:p1-C6H5(CH2)3OH}(PEt3)Cl]BF4 (3b)
The initial procedure was similar to that for 3a.
Recrystallization from CH2Cl2/n-hexane gave an or-
1
mg, 77%). H NMR (CD3OD): l 1.88 (m, 2H), 2.67 (t,
1
ange crystalline product (83%). H NMR (CD2Cl2): l
J=7.8 Hz, 2H), 3.63 (t, J=6.4 Hz, 2H), 5.83 (t,
J=5.7 Hz, 1H), 5.95 (d, J=6.5 Hz, 2H), 6.21 (t,
J=6.4 Hz, 2H), 7.74 (m, 2H), 8.23 (td, J=7.8, 1.4 Hz,
2H), 8.49 (d, J=8.4 Hz, 2H), 9.49 (d, J=4.9 Hz, 2H).
Anal. Calc. for C19H20BClF4N2ORu: C, 44.25; H, 3.91;
N, 5.43. Found: C, 44.54; H, 3.85; N, 5.67.
1.10 (dt, J=15.7, 5.1 Hz 9H), 1.82–2.08 (m, 6H), 2.18
(m, 1H), 2.56–2.67 (m, 1H), 2.69–2.78 (m, 1H), 3.48
(m, 1H), 3.92 (m, 1H), 4.07 (t, J=4.9 Hz, 1H), 4.95 (t,
J=5.1 Hz, 1H), 5.49 (d, J=5.9 Hz, 1H), 5.82 (t,
J=5.4 Hz, 4H), 5.88 (t, J=5.9 Hz, 1H), 6.29 (d,
J=5.9 Hz, 1H). 31P NMR (CD2Cl2): l 32.10 (s). Anal.
Calc. for C15H27BClF4NOPRu: C, 37.72; H, 5.70.
Found: C, 38.03; H, 5.49.
3.1.5. [Ru{p6-C6H5(CH2)3OH}(phen)Cl]BF4 (2b)
This was prepared similarly to 2a (68%). H NMR
1
(CD3OD): l 1.91 (m, 2H), 2.70 (t, J=7.8 Hz, 2H), 3.64
(t, J=6.1 Hz, 2H), 5.85 (t, J=5.9 Hz, 1H), 6.08 (d,
J=6.5 Hz, 2H), 6.32 (t, J=6.1 Hz, 2H), 8.08 (dd,
J=5.4, 3.0 Hz, 2H), 8.20 (s, 2H), 8.49 (dd, J=8.4, 1.6
3.1.9. [Ru {p6:p1-C6H5(CH2)3OH}(bipy)](BF4)2 (4a)
To a solution of 2a (200 mg, 0.388 mmol) in MeOH
(30 ml) was added a solution of AgBF4 (76 mg, 0.388

Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
375
mmol) in MeOH (2 ml) and the mixture was stirred for
14 h. The suspension was filtered and the solvent was
evaporated. Recrystallization from MeOH/ether gave
an orange crystalline product (29%). 1H NMR
(CD3OD): l 2.29 (m, 2H), 2.91 (m, 2H), 3.70 (m, 2H),
5.41 (t, J=5.8 Hz, 1H), 6.22 (d, J=6.5 Hz, 2H), 6.50
(t, J=6.1 Hz, 2H), 7.88 (m, 2H), 8.35 (td, J=9.1, 1.2
Hz, 2H), 8.56 (d, J=8.4 Hz, 2H), 9.68 (d, J=4.9 Hz,
2H) Anal. Calc. for C19H20B2F8N2ORu: C, 40.24; H,
3.55; N, 4.94. Found: C, 40.48; H, 3.39; N, 4.94.
J=5.1, 1.4 Hz, 2H). Anal. Calc. for C21H19BF4-
N2ORu·H2O: C, 48.39; H, 4.06; N, 5.37. Found: C,
48.04; H, 3.85; N, 5.38.
3.1.14. [Ru{p6:p1-C6H5(CH2)3O}(bpop)]BF4 (5c)
1
This was prepared similarly to 5a (91%). H NMR
(CDCl3): l 1.42 (m, 1H), 1.68 (m, 1H), 1.68 (s, 3H),
1.83 (s, 3H), 1.98 (m, 1H), 2.13 (m, 1H), 2.82 (dd,
J=8.1, 11.9 Hz, 1H), 3.36 (dd, J=6.9, 12.3 Hz, 1H),
4.05 (d, J=5.4 Hz, 1H), 4.20–4.30 (m, 3H), 4.39 (dd,
J=6.5, 8.9 Hz, 1H), 4.84 (dd, J=8.9, 10.8 Hz, 1H),
5.19 (dd, J=8.4, 10.8 Hz, 1H), 5.26 (dd, J=6.5, 10.8
Hz, 1H), 5.46 (t, J=5.9 Hz, 1H), 5.92 (dd, J=8.9, 10.8
Hz, 1H), 6.12 (dd, J=5.4, 5.9 Hz, 1H), 7.33–7.59 (m,
10H). Anal. Calc. for C30H33BF4N2O3Ru·H2O: C, 53.34;
H, 5.22; N, 4.15. Found: C, 53.37; H, 5.00; N, 4.16.
3.1.10. [Ru {p6:p1-C6H5(CH2)3OH}(phen)](BF4)2 (4b)
1
This was prepared similarly to 4a (22%). H NMR
(CD3OD): l 2.29 (m, 2H), 2.95 (m, 2H), 3.62 (m, 2H),
5.36 (t, J=5.7 Hz, 1H), 6.36 (d, J=6.2 Hz, 2H), 6.64
(t, J=6.4 Hz, 2H), 8.21 (dd, J=8.1, 5.3 Hz, 2H), 8.27
(s, 2H), 8.96 (dd, J=8.4, 1.6 Hz, 2H), 10.04 (dd,
J=5.4, 1.1 Hz, 2H). Anal. Calc. for C21H20B2F8-
N2ORu: C, 42.67; H, 3.41; N, 4.74. Found: C, 42.66; H,
3.42; N, 4.78.
3.1.15. [Ru{p6:p1-C6H5(CH2)3NH2}(PPh3)Cl]BF4 (7a)
To a solution of hydrated ruthenium trichloride (2.28
g, 8.9 mmol) in ethanol (200 ml) was added
C6H7(CH2)3NH3Cl (7.73 g, 45 mmol) and the mixture
was refluxed for 4 h. The brown precipitate was filtered
off, washed with ether, and dried in vacuo to give the
chloride dimer (3.02 g, 99%). To the suspension of
[Ru{h6-C6H5(CH2)3NH3Cl}Cl2]2 (1.00 g, 2.90 mmol/
Ru) in MeCN (80 ml) was added triphenylphosphine
(773 mg, 2.95 mmol) and the mixture was stirred for 11
h at r.t. to give an orange suspension. The suspension
was filtered off to give orange powders 6a (92%). To
the suspension of 6a (495 mg, 0.82 mmol) in MeOH
(100 ml) was added a solution of NaOH (33 mg, 0.82
mmol) in MeOH (5 ml) and the mixture was stirred for
15 min at r.t. Then, NaBF4 (159 mg, 0.82 mmol) was
added to the suspension and the mixture was stirred for
15 h at r.t. The suspension was filtered and the filtrate
was evaporated. The residue was recrystallized with hot
MeOH to give 244 mg (0.39 mmol, 48%) of orange
3.1.11. [Ru{p6:p1-C6H5(CH2)3OH}(bpop)](BF4)2 (4c)
This was prepared from 2c in CH2Cl2 and AgBF4 in
MeOH. Recrystallization from MeOH/ether gave an
1
orange crystalline product (74%). H NMR (CDCl3): l
1.43 (m, 1H), 1.37 (s, 3H), 1.79 (m, 1H), 1.89 (s, 3H),
2.05 (m, 1H), 2.18 (m, 1H), 2.41 (m, 1H), 3.55 (m, 1H),
4.48–4.57 (m, 2H), 4.63 (t, J=5.9 Hz, 2H), 4.77 (d,
J=5.9 Hz, 1H), 4.78 (brs, 1H), 5.19 (dd, J=8.4, 10.5
Hz, 1H), 5.30–5.40 (m, 4H), 5.97 (dd, J=6.9, 10.4 Hz,
1H), 6.89 (t, J=5.9 Hz, 1H), 7.32–7.64 (m, 10H). Anal.
Calc. for C30H34B2F8N2O3Ru·2H2O: C, 46.12; H, 4.90;
N, 3.59. Found: C, 45.98; H, 4.53; N, 3.62.
3.1.12. [Ru{p6:p1-C6H5(CH2)3O}(bipy)]BF4 (5a)
To a solution of 4a (80 mg, 0.141 mmol) in MeOH (7
ml) was added NaOH (6 mg, 0.15 mmol) and the
mixture was stirred for 1 min at 0°C. The solvent was
evaporated under vacuum. The residue was extracted
with CH2Cl2, and the solvent evaporated. The remain-
ing solids were recrystallized from MeOH/ether to give
46 mg (69%) of orange crystalline product 5a. 1H NMR
(CD3OD): l 2.17 (m, 2H), 2.72 (m, 2H), 3.47 (m, 2H),
5.38 (t, J=5.8 Hz, 1H), 5.66 (d, J=5.7 Hz, 2H), 6.12
(t, J=6.2 Hz, 2H), 7.74 (m, 2H), 8.22 (td, J=7.8,
J=1.6 Hz, 2H), 8.47 (d, J=8.4 Hz, 2H), 9.39 (d,
J=4.9 Hz, 2H) Anal. Calc. for C19H19BF4N2ORu·H2O:
C, 45.89; H, 4.26; N, 5.63. Found: C, 45.81; H, 4.32;N,
5.64.
1
crystalline product 7a. H NMR (CDCl3): l 1.99 (brs,
1H), 2.17–2.33 (m, 2H), 2.51 (m, 2H), 4.08 (brs, 1H),
4.24 (brs, 1H), 5.45 (brs, 1H), 5.81–5.84 (m, 2H), 6.02
(d, J=5.9 Hz, 1H), 7.53–7.57 (m, 15H). 31P NMR
(CDCl3): l 36.13 (s). Anal. Calc. for C27H28BClF4-
NPRu: C, 52.24; H, 4.55; N, 2.26. Found: C, 52.02; H,
4.63; N, 2.26.
3.1.16. [Ru{p6:p1-C6H5(CH2)2NH2}(PPh3)Cl]BF4 (7b)
1
This was prepared similarly to 7a (42%). H NMR
(CDCl3): l 2.18 (s, 1H), 2.60–2.67 (m, 1H), 3.35–3.44
(m, 1H), 3.92 (brs, 2H), 4.32 (q, J=5.4 Hz, 1H), 4.85
(brs, 1H), 5.44 (t, J=5.4 Hz, 1H), 5.61 (d, J=5.4 Hz,
1H), 5.96 (d, J=5.4 Hz, 1H), 6.15 (t, J=5.9 Hz, 1H),
7.52–7.61 (m, 15H). 31P NMR (CDCl3): l 34.54 (s).
Anal. Calc. for C26H26BClF4NPRu·H2O: C, 49.98; H,
4.52; N, 2.24. Found: C, 49.97; H, 4.39; N, 2.32.
3.1.13. [Ru{p6:p1-C6H5(CH2)3O}(phen)]BF4 (5b)
This was prepared similarly to 5a (62%). H NMR
(CD3OD): l 2.16 (m, 2H), 2.77 (m, 2H), 3.40 (m, 2H),
5.34 (t, J=5.7 Hz, 1H), 5.82 (d, J=5.9 Hz, 2H), 6.25
(t, J=6.1 Hz, 2H), 8.04 (dd, J=8.1, 5.1 Hz, 2H), 8.18
(s, 2H), 8.81 (dd, J=8.4, 0.81 Hz, 2H), 9.74 (dd,
1

376
Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
3.1.17. [Ru{p6-C6H5(CH2)3NMe2}(PPh3Cl2] (9)
C16H25ClOF6P2Ru: C, 35.21; H, 4. 62. Found: C, 35.03;
H, 4.70.
Complex 8 was prepared similarly to 6a (90%). To
the suspension of 8 (570 mg, 0.91 mmol) in MeOH (50
ml) was added a solution of KOH (51 mg, 0.91 mmol)
in MeOH (5 ml) and the mixture was stirred for 10 min
at r.t. The solution was evaporated, and the residue was
extracted with AcOEt. Recrystallization with benzene/
n-hexane gave 279 mg (0.46 mmol, 51%) of orange
crystalline product 9. 1H NMR (CDCl3): l 1.75 (m,
2H), 2.13 (s, 6H), 2.26 (t, J=7.3 Hz, 2H), 2.57 (t,
J=7.8 Hz, 2H), 4.48 (t, J=5.4 Hz, 1H), 5.10 (t,
J=5.4 Hz, 2H), 5.22 (d, J=7.8 Hz, 2H), 7.28–7.74 (m,
15H). 31P NMR (CDCl3): l 28.35 (s). Anal. Calc. for
C29H29Cl2NPRu: C, 58.29; H, 5.40; N, 2.34. Found: C,
58.06; H, 5.11; N, 2.32.
3.2. Crystal structure determination
All data were obtained on a Rigaku AFC-5R (2a, 4b,
and 4c) or R-AXIS RAPID (5a) diffractometer with
graphite-monochromated Mo Ka radiation. All calcu-
lations were carried out with the TEXAN crystallo-
graphic software package of Molecular Structure Corp.
The structures of 2a, 4b, 4c, and 5a were solved by
direct methods and refined by full-matrix least-squares
procedures, the function minimized being Sw(ꢀFoꢀ−
ꢀFcꢀ)2. The non-hydrogen atoms were refined anisotropi-
cally. Part of the hydrogens was positioned by stereo-
chemical consideration.
3.1.18. [Ru{p6:p1-C6H5(CH2)3OPPh2}Cl2] (10a)
Crystal data for 2a: C19H20BClF4N2ORu, M=
515.71, monoclinic, space group P21/n (no. 14), a=
To a suspension of [Ru{h6-C6H5(CH2)3OH}Cl2]2
(1.034 g, 3.36 mmol/Ru) in MeCN (100 ml) was added
chlorodiphenylphosphine (0.602 ml, 3.36 mmol) and
the mixture was stirred for 1 h at r.t. to give a red
solution. A solution of ethyldiisopropylamine (0.585
ml, 3.36 mmol) in MeCN (90 ml) was added dropwise
to the red solution at 0°C for 1.5 h. and then the
mixture was stirred at r.t. for 24 h. The solvent was
removed under vacuum, and the residue was extracted
with CH2Cl2/H2O. Recrystallization with hot CH2Cl2
,
8.505(2), b=9.390(2), c=24.879(3) A, V=2922.7(9)
,
3
A , Z=4, F(000)=1032, Dc=1.724 g cm−3, m(Mo
Ka)=9.73 cm−1, 257 variable refined with 3443 reflec-
tions with I\3|(I) to R=0.038, Rw=0.038.
Crystal data for 4b: C21H20B2F8N2ORu, M=591.08,
(
triclinic, space group P1 (no. 2), a=10.002(2), b=
3
,
,
11.714(2), c=9.722(2) A, V=1117.7(4) A , Z=2,
F(000)=588, Dc=1.756 g cm−3, m(Mo Ka)=7.86
cm−1, 316 variable refined with 4874 reflections with
I\3|(I) to R=0.043, Rw=0.064.
1
gave orange powders 10a (44%). H NMR (CDCl3): l
2.19 (m, 2H), 2.80 (t, J=5.4 Hz, 2H), 4.85 (dt, J=
16.7, 6.1 Hz, 2H), 5.14 (d, J=5.4 Hz, 2H),5.76 (t,
J=6.1 Hz, 2H), 6.27 (t, J=6.6 Hz, 1H), 7.36–7.93 (m,
10H). 31P NMR (CDCl3): l 119.01 (s). Anal. Calc. for
C21H21Cl2OPRu: C, 51.25; H, 4.30. Found: C, 50.95; H,
4.10.
Crystal data for 4c: C30H34B2F8N2O3Ru·2H2O, M=
781.32, monoclinic, space group P21 (no. 4), a=
,
9.304(1), b=19.063(2), c=10.485(2) A, V=1745.6(4)
3
A , Z=2, F(000)=796, Dc=1.486 g cm−3, m(Mo
,
Ka)=5.31 cm−1, 479 variable refined with 2563 reflec-
tions with I\3|(I) to R=0.099, Rw=0.124.
Crystal data for 5a: C19H19BF4N2ORu·CH3OH,
M=511.29, monoclinic, space group P21/c (no. 14),
3.1.19. [Ru{p6:p1-C6H5(CH2)3OPiPr2}Cl2] (10b)
This was prepared similarly to 10a (25%). H NMR
1
,
a=9.5919(5), b=14.0615(7), c=15.4174(9) A, V=
3
−3
,
(CDCl3): l 1.27 (m, 12H), 2.09 (tt, J=6.4, 5.4 Hz, 2H),
2.77 (t, J=6.4 Hz, 2H), 3.04 (m, 2H), 4.27 (dt, J=
13.8, 5.4 Hz, 2H), 5.55 (d, J=4.9 Hz, 2H), 5.77 (t,
J=5.9 Hz, 2H), 6.20 (t, J=6.2 Hz, 1H). 31P NMR
(CDCl3): l 156.97 (s). Anal. Calc. for C15H25Cl2OPRu:
C, 42.46; H, 5.94. Found: C, 42.25; H, 5.71.
2078.4(2) A , Z=4, F(000)=960, Dc=1.531 g cm
,
m(Mo Ka)=8.00 cm−1, 271 variable refined with 3323
reflections with I\3|(I) to R=0.074, Rw=0.079.
4. Supplementary material
3.1.20. [Ru{p6:p1-C6H5(CH2)3OPiPr2}(CO)Cl]PF6 (11)
To a suspension of AgPF6 (25.8 mg, 0.102 mmol)
and 10b (43.3 mg, 0.102 mmol) in CH2Cl2 (10 ml) was
bubbled CO gas for 3 min at r.t. The yellow suspension
was filtered and the solvent was removed under vac-
cum. The yellow powder was washed with ether to give
Crystallographic details, atomic coordinates, aniso-
tropic displacement parameters, bond lengths and an-
gles, and structure factors for 2a, 4b, 4c, and 5a are
available from the authors on request.
1
11 (89%). H NMR (CD2Cl2): l 1.16–1.34 (m, 12H),
Acknowledgements
2.12–2.36 (m, 2H), 2.61–2.76 (m, 1H), 3.00–3.15 (m,
3H), 4.14–4.23 (m, 1H), 4.44–4.59 (m, 1H), 6.37–6.41
(m, 2H), 6.64 (d, J=6.2 Hz, 1H), 6.67 (t, J=6.6 Hz,
1H), 6.87–6.91 (m, 1H). 31P NMR (CD2Cl2): l
168.09 (s). IR (KBr) 2035 cm−1. Anal. Calc. for
Thanks are due to Professor Y. Kai and Dr N.
Kanehisa for advice on X-ray structural analysis, and
to the Analytical Center, Faculty of Engineering, Osaka
University for NMR facilities.

Y. Miyaki et al. / Inorganica Chimica Acta 300–302 (2000) 369–377
377
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