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Volumn 3, Issue 12, 2001, Pages 1937-1939

Optically active β-ketoiminato cationic cobalt(III) complexes: Efficient catalysts for enantioselective carbonyl-ene reaction of glyoxal derivatives

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Indexed keywords

ARTICLE;

EID: 0012809298     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol015980m     Document Type: Article
Times cited : (68)

References (29)
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    • The ketoiminato cobalt(II) complexes effectively catalyzed the enantioselective borohydride reductions of ketones, imines, and α,β-unsaturated carboxamides and the enantioselective cyclopropanation of styrene derivatives: Nagata, T.; Yorozu, K.; Yamada, T.; Mukaiyama, T. Angew. Chem., Int. Ed. Engl. 1995, 34, 2145. Sugi, K. D.; Nagata, T.; Yamada, T.; Mukaiyama, T. Chem. Lett. 1997, 493. Yamada, T.; Ohtsuka, Y.; Ikeno, T. Chem. Lett. 1998, 1129. Yamada, T.; Ikeno, T.; Sekino, H.; Sato, M. Chem. Lett. 1999, 719. Ikeno, T.; Sato, M.; Yamada, T. Chem. Lett. 1999, 1345.
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    • note
    • 3 was the most suitable solvent to afford the corresponding homoallylic alcohol in high yield and with high enantioselectivity. The enantioselectivity at 0°C was lower than that at -20°C. Although the enantioselectivity at -40°C was slightly improved, the reaction rate was decreased.
  • 27
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    • note
    • For the present carbonyl-ene reaction, mono- and trisubstituted alkenes were not reactive enough to the glyoxal derivatives.
  • 29
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    • note
    • The absolute configuration of the resulting pyranone derivatives in the cobalt-complex-catalyzed hetero Diels-Alder reaction was explained by the semiempirical method; ref 6b.


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