Y. Arikawa et al. / Journal of Organometallic Chemistry 572 (1999) 163–168
167
3. Experimental
added, and then the resulting solution was magnetically
stirred at r.t. for 20 h. The original purple solution
changed to a red suspension. After addition of hexane
(20 ml), the reaction mixture was filtered. Recrystalliza-
tion of the resultant solid from dichloromethane/n-hex-
ane gave 6 (375 mg, 0.41 mmol, 81%) as red crystals.
1H-NMR l 0.57 (d, 3H, J=7 Hz), 0.97 (d, 3H, J=7
Hz), 2.12 (dd, 1H, J=8 and 8 Hz), 3.21 (m, 1H), 3.28
(m, 1H), 3.80 (dd, 1H, J=3 and 8 Hz), 4.02 (s, 5H),
4.59 (m, 1H), 4.68 (m, 1H), 4.84 (m, 1H), 6.5–8.4 (m,
25H). 31P-NMR l 40.1 (d, J=45 Hz), 77.0 (d, J=45
Hz). Anal Calc. for C46H43Cl2FeNOP2Ru: C, 60.34; H,
4.73; N, 1.53. Found: C, 60.30; H, 4.89; N, 1.52.
1H- (270 MHz) and 31P-NMR spectra (109 MHz)
were recorded on a JEOL JNM-EX-270 or JEOL GSX-
270 spectrometer as solutions in CDCl3. GLC analyses
were performed on a Hitachi 163 instrument (1 m×3
mm stainless steel column packed with 20% EGSS on
Shimalite) and a Shimadzu GC-14A instrument (25 m
HiCap-CBP-10-S25 capillary column) with flame-ion-
ization detectors and N2 as carrier gas. Column chro-
matographies on SiO2 were performed with Wakogel
C-300 (hexane and hexane/ethyl acetate as eluents). All
the solvents were distilled from CaH2 or LiAlH4 and
˚
stored over molecular sieves 4 A under nitrogen. All the
starting ketones and the resultant alcohols are known
compounds and commercially available.
3.3. X-ray structural determination of 6
Data for 6 (a red crystal, grown by slow diffusion of
diethyl ether into a dichloromethane solution of 6 at
r.t.) of C46H43Cl2FeNOP2Ru was collected on a Rigaku
AFC7R diffractometer with graphite monochromated
3.1. Typical procedure for asymmetric transfer
hydrogenation of ketones with a ruthenium(II) complex
and a chiral ligand or a ruthenium(II)–chiral ligand
complex
˚
Mo–Kh radiation (u=0.71069 A) and a 12 kW rotat-
ing anode generator at 25°C using the ꢀ–2q scan
technique. No significant decay was observed for three
standard reflections that were monitored every 150
reflections. The two independent molecules of 6 each
occupy a unit cell. The structures of these two indepen-
dent molecules are almost the same. The selected bond
lengths and angles are summarized in Table 3. Crystal
In a 10-ml round-bottomed flask equipped with a
reflux condenser RuCl2(PPh3)3 (4.79 mg, 5.0×10−3
mmol) and oxazolinylferrocenylphosphine 2 (2.72 mg,
5.5×10−3 mmol) or the isolated complex
[RuCl2 ·3·(PPh3)] (4.58 mg, 5.0×10−3 mmol) were
placed under nitrogen. 2-Propanol (2.5 ml) was added
and then the mixture was magnetically stirred and
heated to reflux for 30 min. A solution of acetophenone
(600.6 mg, 5.0 mmol) in 2-propanol (1.5 ml) was added
and the mixture was refluxed for 30 min. The reaction
was started by the addition of 0.125 N NaOH/2-
propanol solution (1.0 ml) and the solution was kept at
reflux for an appropriate time and then quenched with
HCl (1 N, 5.0 ml). The mixture was taken up in diethyl
ether, washed with H2O, NaHCO3, and then brine. For
GLC analyses, dibenzyl was added as an internal stan-
dard. For isolation, the extract was dried over anhy-
drous MgSO4 and concentrated under reduced pressure
by an aspirator. The residue was purified by column
chromatography to provide the corresponding alcohol.
The ee value and the configuration of the alcohols were
determined by HPLC on a Daicel Chiralcel OJ, OD,
OB and OF columns (2-propanol/hexane as eluent).
The ee values of 2-octanol, 1-cyclohexylethanol and
3,3-dimethyl-2-butanol were determined by GLC of the
corresponding acetate or trifluoroacetate using Chi-
raldex GT-A (30 m).
(
data [16] for 6 are as follows: triclinic, space group P1
˚
(No. 1); a=12.032(4), b=19.461(6), c=10.570(3) A;
h=98.41(3)°, i=113.62(2)°, k=73.40(3)°; V=2171(1)
3
A ; Z=2; Dcalc. =1.400 g cm−3; v(Mo–Kh)=9.13
˚
cm−1. For structure analysis and refinement, computa-
tions were performed using TEXSAN [17] crystallo-
graphic software package of molecular structure. The
final R value was 0.063 (Rw=0.079) for 5906 unique
reflections with I\3|(I). The structure was solved by
Patterson method (DIRDIF92 PATTY). The carbon
atoms of phenyl rings were refined isotropically. All
other non-hydrogen atoms were refined anisotropically.
Hydrogen atoms were included but not refined.
Acknowledgements
The present work was supported in part by a Grant-
in-Aid for Scientific Research from the Ministry of
Education, Science and Culture, Japan.
3.2. Preparation of ruthenium complex
[RuCl2 ·3 ·(PPh3)] (6)
References
[1] For recent reviews, see: G. Zassinovich, G. Mestroni, S. Gladiali,
Chem. Rev. 92 (1992) 1051.
[2] C.F. de Graauw, J.A. Peters, H. van Bekkum, J. Husken,
Synthesis (1994) 1007.
In a 20-ml round-bottomed flask, the RuCl2(PPh3)3
(480 mg, 0.50 mmol) and 3 (240 mg, 0.50 mmol) were
placed under nitrogen. Anhydrous toluene (15 ml) was