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2. (a) Conticello, V. P.; Brard, L.; Giardello, M. A.; Tsuji, Y.; Sabat, M.; Stern, C. L.; Marks, T. J. J. Am. Chem.
Soc. 1992, 114, 2761–2762. (b) Giardello, M. A.; Conticello, V. P.; Brard, L.; Gagne´, M. R.; Marks, T. J. J. Am.
Chem. Soc. 1994, 116, 10241–10254.
3. Noyori, R. Asymmetric Catalysis in Organic Synthesis; Wiley: New York, 1994; Chapter 2.
4. Recent reviews: (a) Pfaltz, A. In Methods of Organic Chemistry (Houben-Weyl), 4th ed.; Helmchen, G.;
Hoffmann, R. W.; Mulzer, J.; Schaumann, E., Eds.; Thieme: Stuttgart, 1995; Vol. E21d, pp. 4334–4359. (b) Burk,
M. J.; Bienewald, F. In Transition Metals for Organic Synthesis; Beller, M.; Bolm, C., Eds.; Wiley-VCH:
Weinheim, 1998; Vol. 2, pp. 13–25. (c) Brown, J. M. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N.;
Pfaltz, A.; Yamamoto, H., Eds.; Springer: Berlin, 1999; Vol. 1, Chapter 5.1. (d) Ohkuma, T.; Kitamura, M.;
Noyori, R. In Catalytic Asymmetric Synthesis, 2nd ed.; Ojima, I., Ed.; Wiley-VCH: New York, 2000; Chapter 1.
5. (a) Landis, C. R.; Halpern, J. J. Am. Chem. Soc. 1987, 109, 1746–1754. (b) Kitamura, M.; Yoshimura, M.;
Tsukamoto, M.; Noyori, R. Enantiomer 1996, 1, 281–303. (c) Wiles, J. A.; Bergens, S. H.; Young, V. G. J. Am.
Chem. Soc. 1997, 119, 2940–2941.
6. Halterman, R. L. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N.; Pfaltz, A.; Yamamoto, H., Eds.;
Springer: Berlin, 1999; Vol. 1, Chapter 5.2.
7. Ohta, T.; Ikegami, H.; Miyake, T.; Takaya, H. J. Organomet. Chem. 1995, 502, 169–176. BINAP=2,2%-
bis(diphenylphosphino)-1,1%-binaphthyl.
8. The reactivity of Ru-catalyzed hydrogenation is highly dependent on the substitution pattern of olefins (Hallman,
P. S.; McGarvey, B. R.; Wilkinson, G. J. Chem. Soc. A 1968, 3143–3150) and decreases in the order of terminal
alkenes>styrenes>a-alkylstyrenes.
9. A cationic diphosphine–Rh complex in benzene is activated by tetrabutylammonium iodide. See: Buriak, J. M.;
Klein, J. C.; Herrington, D. G.; Osborn, J. A. Chem. Eur. J. 2000, 6, 139–150.
10. Lightfoot, A.; Schnider, P.; Pfaltz, A. Angew. Chem., Int. Ed. 1998, 37, 2897–2899.
11. Halterman, R. L.; Vollhardt, K. P. C.; Welker, M. E.; Bla¨ser, D.; Boese, R. J. Am. Chem. Soc. 1987, 109,
8105–8107. The reported optical yield of 96% was actually 77%.6 See also: Paquette, L. A.; Sivik, M. R.; Bzowej,
E. I.; Stanton, K. J. Organometallics 1995, 14, 4865–4878.
12. Chiral titanocenes and zirconocenes effect the enantioselective reaction of tri- and tetrasubstituted aromatic
olefins (S/C=13–20, 68–136 atm, rt to 65°C, 83>99% ee). See: (a) Broene, R. D.; Buchwald, S. L. J. Am. Chem.
Soc. 1993, 115, 12569–12570. (b) Troutman, M. V.; Appella, D. H.; Buchwald, S. L. J. Am. Chem. Soc. 1999, 121,
4916–4917.
13. (a) Kitamura, M.; Tokunaga, M.; Ohkuma, T.; Noyori, R. Tetrahedron Lett. 1991, 32, 4163–4166. (b) Kitamura,
M.; Tokunaga, M.; Ohkuma, T.; Noyori, R. Org. Synth. 1993, 71, 1–13.
14. Me-DuPhos=1,2-bis(2,5-dimethylphospholano)benzene. Burk, M. J.; Feaster, J. E.; Nugent, W. A.; Harlow, R.
L. J. Am. Chem. Soc. 1993, 115, 10125–10138.
15. Preparation of RuCl2[(R,R)-Me-DuPhos](dmf)n: (R,R)-Me-DuPhos (99.8 mg, 0.326 mmol) and [RuCl2(C6H6)]2
(82.0 mg, 0.164 mmol) were placed in a 100-mL Schlenk flask. After the air was replaced with argon, dry
degassed DMF (2 mL) was added and the mixture was stirred under argon at 100°C for 2 h to form a brown
solution. The solvent was evaporated under reduced pressure, and the residue was dissolved in a 1:1 mixture of
ether and CH2Cl2 (5 mL). The turbidity was removed by filtration under argon, and the filtrate was concentrated
to approximately 3 mL. The turbidity was again removed by filtration. Hexane (3 mL) was added, and the
turbidity was removed by filtration. Upon concentration of the filtrate to approximately 2 mL, a bright yellow
powder precipitated. The supernatant was removed, and the resulting solid was dried under reduced pressure to
give oligomeric RuCl2[(R,R)-Me-DuPhos](dmf)n (83.1 mg). 31P NMR (202 MHz, C6D6): l 97.9 (d, J=26 Hz),
99.1 (d, J=30 Hz), 99.5 (d, J=28 Hz), 102.4 (d, J=32 Hz). This complex should be stored under an argon
atmosphere.
16. RuCl2[(R,R)-Me-DuPhos](dmf)n (1.5 mg, 0.0024 mmol, calculated as n=2) was placed in a 100-mL glass
autoclave equipped with a Teflon-coated magnetic stirring bar, and the air in this apparatus was replaced with
argon. 2-Propanol (1.2 mL), 1f (1.26 g, 6.29 mmol), and a 1.0 M t-C4H9OK solution in t-butyl alcohol (47 mL,
0.047 mmol) were added to the autoclave, and the mixture was degassed. Hydrogen was introduced into the
autoclave at a pressure of 8 atm. The reaction mixture was vigorously stirred at 20°C for 16 h. The conversion
determined by GC was 99.5%. GC [Chirasil-DEX CB, df=0.25 mm, 0.32 mm i.d.×25 m, CHROMPACK; carrier
gas, helium (26 kPa); column temp., 89°C; retention time (tR) of (R)-2f, 34.0 min (90.0%); tR of S isomer 32.9
min (9.5%); tR of 1f, 42.9 min (0.5%)]. After the reaction, the solvent was removed under reduced pressure, and
the residue was purified by bulb-to-bulb distillation to give (R)-2f (1.18 g, 93% yield, 81% ee). No starting