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Application of new unsymmetrical chiral Mn(III), Co(II,III) and Ti(IV) salen complexes in enantioselective catalytic reactions


New unsymmetrical chiral salen complexes were synthesized and the efficiency of Mn(III), Ti(IV), Co(II) and Co(III) type catalysts were examined in the enantioselective epoxidation of styrene and α‐methylstyrene, the trimethylsilylcyanation of benzaldehyde, the borohydride reduction of aromatic ketones and asymmetric hydrolysis of epoxides to diols, respectively. A very high level of enantioselectivity was attainable over the unsymmetrical chiral salen complexes prepared mainly from salicylaldehyde and 2‐formyl‐4,6‐di‐tert‐butylphenol derivatives. Enantiomeric excess of the corresponding reaction product obtained using unsymmetrical chiral salen catalysts was generally higher than that over conventional symmetric chiral salen catalysts.

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  1. W. Zhang, J.L. Loebach, S.R. Wilson and E.N. Jacobson, J. Am. Chem. Soc. 112 (1990) 2801.

    CAS  Article  Google Scholar 

  2. M. Palucki, P.J. Pospisil, W. Zhang and E.N. Jacobson, J. Am. Chem. Soc. 116 (1994) 9333.

    CAS  Article  Google Scholar 

  3. R. Irie, K. Noda, Y. Ito, N. Matsumoto and T. Katsuki, Tetrahedron Lett. 31 (1990) 7345.

    CAS  Article  Google Scholar 

  4. K.B.M. Janssen, I.L. Laquiere, W. Dehaen, R.F. Parton, I.F.J. Vankelecom and P.A. Jacobs, Tetrahedron: Asymmetry 8 (1997) 3481.

    CAS  Article  Google Scholar 

  5. L.E. Martinez, J.L. Leighton, D.H. Carsten and E.N. Jacobson, J. Am. Chem. Soc. 117 (1995) 5897.

    CAS  Article  Google Scholar 

  6. Y. Belokon, N. Ikonnikov, M, Moscalenko, M. North, S. Orlova, V. Tararov and L. Yashkina, Tetrahedron: Asymmetry 7 (1996) 851; (b) Y. Belokon, M. Moscalenko, N. Ikonnikov, L. Yashkina, D. Antonov, E. Vorontsov and V. Rozenberg, Tetrahedron: Asymmetry 8 (1997) 3245.

    CAS  Article  Google Scholar 

  7. M. Hayashi, Y. Miyamoto, T. Inoue and N. Oguni, J. Org. Chem. 58 (1993) 1515; (b) M. Hayashi, T. Inoue, Y. Miyamoto and N. Oguni, Tetrahedron 50 (1994) 4385; (c) M. Hayashi and N. Oguni, J. Synth. Org. Chem. Jpn. (1994) 488.

    CAS  Article  Google Scholar 

  8. M. Tokunaga, J.F. Larrow, F. Kakiuchi and E.N. Jacobson, Science 277 (1997) 936.

    CAS  Article  Google Scholar 

  9. T. Nagata, K.D. Sugi, K. Yorozu, T. Yamada and T. Mukaiyama, Catal. Surveys Jpn. 2 (1998) 47.

    CAS  Article  Google Scholar 

  10. J. Lopez, S. Liang and X.R. Bu, Tetrahedron Lett. 39 (1998) 4199.

    CAS  Article  Google Scholar 

  11. E.N. Jacobson, W. Zhang, A.R. Muci, J.R. Ecker and L. Deng, J. Am. Chem. Soc. 113 (1991) 7063.

    Article  Google Scholar 

  12. K.B.M. Janssen, R.F. Parton and P.A. Jacobs, Tetrahedron: Asymmetry 8 (1997) 3039.

    CAS  Article  Google Scholar 

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Correspondence to Geon‐Joong Kim.

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Kim, G., Shin, J. Application of new unsymmetrical chiral Mn(III), Co(II,III) and Ti(IV) salen complexes in enantioselective catalytic reactions. Catalysis Letters 63, 83–90 (1999).

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  • unsymmetrical chiral salen
  • epoxidation
  • reduction
  • hydrolysis
  • trimethylsilylcyanation
  • enantioselectivity