Enantioselective conjugate addition of diethylzinc to enones catalyzed by a copper complex of chiral aryl diphosphite

(Note: The full text of this document is currently only available in the PDF Version )

Ming Yan, Li-Wei Yang, Kwok-Yin Wong and Albert S. C. Chan


Abstract

The 1,4-conjugate addition of diethylzinc to cyclohex-2-enone and cyclopent-2-enone catalyzed by a copper complex of a chiral aryl diphosphite gave the desired products with 90.2 and 76.6% ee respectively.


References

  1. Reviews: R. Noyori, Asymmetric Catalysis in Organic Synthesis, VCH, New York, 1993 Search PubMed; P. Prelmutter, Conjugate Addition Reactions in Organic Synthesis, Pergamon, Oxford, 1992 Search PubMed; Advanced Asymmetric Synthesis, ed. G. R. Stephenson, Chapman & Hall, London, 1996 Search PubMed; Advances in Catalytic Processes, ed. M. P. Doyle, JAI Press, Greemwich, Connecticut, 1995, vol. 1 Search PubMed; B. E. Rossiter and H. M. Swingle, Chem. Rev., 1992, 92, 771 Search PubMed; N. Krause, Angew. Chem., Int. Ed., 1998, 37, 283 Search PubMed.
  2. (a) C. L. Gibson, Tetrahedron: Asymmetry, 1996, 7, 3357 CrossRef CAS; (b) A. H. M. de Vries and B. L. Feringa, Tetrahedron: Asymmetry, 1997, 8, 1377 CrossRef CAS; (c) A. H. M. de Vries, R. Imbos and B. L. Feringa, Tetrahedron: Asymmetry, 1997, 8, 1467 CrossRef CAS; (d) Recently NiII catalysts containing chiral diphosphine ligands were used in asymmetric addition of Grignard reagents to unsaturated cyclic acetals with moderate enantioselectivity: see E. Gomez-Bengoa, N. M. Heron, M. T. Didiuk, C. A. Lachaco and A. H. Hoveyda, J. Am. Chem. Soc., 1998, 120, 7649 Search PubMed.
  3. A. Alexakis, J. Vastra, J. Burton and P. Mangency, Tetrahedron: Asymmetry, 1997, 8, 3193 CrossRef CAS.
  4. (a) A. H. M. de vries, A. Meetsma and B. L. Feringa, Angew. Chem., Int. Ed. Engl., 1996, 35, 2374 CrossRef CAS; (b) F. Y. Zhang and A. S. C. Chan, Tetrahedron: Asymmetry, 1998, 9, 1179 CrossRef CAS; (c) E. Keller, J. Maurer, R. Naasz, T. Schader, A. Meetsma and B. L. Feringa, Tetrahedron: Asymmetry, 1998, 9, 2409 CrossRef CAS.
  5. A. Alexakis, J. Burton, J. Vastra and P. Mangency, Tetrahedron: Asymmetry, 1997, 8, 3987 CrossRef CAS.
  6. D. Seebach, G. Jaeschke, A. Pichota and L. Audergon, Helv. Chim. Acta., 1997, 80, 2515 CAS.
  7. T. Mori, K. Kosaka, Y. Nakagawa, Y. Nagaoka and K. Tomioka, Tetrahedron: Asymmetry, 1998, 9, 3175 CrossRef CAS.
  8. B. L. Feringa, M. Pineschi, L. A. Arnold, R. Imbos and A. H. M. de Vries, Angew. Chem., Int. Ed. Engl., 1997, 36, 2620 CrossRef CAS.
  9. A. K. H. Knobel, I. H. Escher and A. Pfaltz, Synlett, 1997, 1429.
  10. Selected data for (S,S,S)-1 containing 0.5EtOH (solvent of crystallization): Calc. for C60H36O6P2·0.5C2H6O: C, 78.12; H, 4.16%. Found: C, 78.13; H, 4.16%; δP(CDCl3) 145.7; δH(CDCl3, 400MHz) 7.97 (d, J 8.8, 2H), 7.90 (d, J 8.0, 2H), 7.82 (dd, J1 8.0, J2 8.8, 4H), 7.73 (d, J 8.0, 2H), 7.52 (d, J 8.8, 2H), 7.37 (m, 8H), 7.16–7.31 (m, 14H), 6.53 (d, J 8.8, 2H), 3.72 (q, J 6.8, 1H), 2.36 (s, 0.5H), 1.24 (t, J 6.8, 1.5H); δC(CDCl3) 147.2, 147.0, 146.5, 134.2, 132.7, 132.2, 131.4, 131.0, 130.8, 130.2, 130.0, 129.5, 128.3, 128.2, 128.1, 126.9, 126.8, 126.2, 126.0, 125.8, 125.1, 124.9, 124.6, 124.2, 122.4, 121.8, 121.7, 121.1; m/z(ESI) 915 (M++ 1, 100%); Mp 196–198 °C (decomp.); [α]D20+346.6 (c 1.085, THF)[a rather different [α]D20 value was reported by Pringle et al.(ref. 11)].
  11. M. J. Baker and P. G. Pringle, J. Chem. Soc., Chem. Commun., 1991, 1292 RSC.
  12. G. H. Posner and L. L. Frye, Isr. J. Chem., 1984, 24, 88 CAS.
  13. B. E. Rossiter, M. Eguchi, G. B. Miao, N. M. Swingle, A. E. Hernandez, D. Vickers, E. Fluckiger, R. G. Patterson and K. V. Reddy, Tetrahedron, 1993, 49, 965 CrossRef CAS.
  14. R. K. Dieter and M. Tokles, J. Am. Chem. Soc., 1987, 109, 2040 CrossRef CAS.
Click here to see how this site uses Cookies. View our privacy policy here.