Design and Evaluation of a Practical Camphor-Based Methyl Ketone Enolate for Highly Stereoselective "Acetate" Aldol Reactions

Angewandte Chemie - International Edition

Volumn 37, Issue 1-2, 1998, Pages 180-182

  Palomo, Claudio ^a   Gonźalez, Alberto ^b   García, Jesús M ^b   Landa, Cristina ^b   Oiarbide, Mikel ^a   Rodríguez, Santiago ^d   Linden, Anthony ^c  

^a UNIVERSITY OF THE BASQUE COUNTRY UPV EHU   (Spain)

^b PUBLIC UNIVERSITY OF NAVARRE   (Spain)

^c UNIVERSITY OF ZURICH   (Switzerland)

^d UNIVERSITAT JAUME I   (Spain)

Author keywords

Acetylene; Aldol reactions; Asymmetric synthesis; Camphor; Methyl ketone

Indexed keywords

EID: 0031930023     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/(sici)1521-3773(19980202)37:1/2<180::aid-anie180>3.0.co;2-4     Document Type: Article

References (60)

1. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
2. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
3. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
4. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
5. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
6. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
7. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
8. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
9. Reviews on the asymmetric aldol condensation: a) D. A. Evans, J. V. Nelson, T. R. Taber, Top. Stereochem. 1982, 13, 1: b) S. Masamune, W. Choy, J. S. Petersen, L. R. Sila, Angew. Chem. 1985, 97, 1; Angew. Chem. Int. Ed. Engl. 1985, 24, 1; c) Comprehensive Organic Chemistry, Vol. 2 (Eds.: B. M. Trost, I. Fleming, C. H. Heathcock), Pergamon, Oxford, 1991; d) C. H. Heathcock in ref. [1c], p. 133; e) M. Kim, S. F. Williams, S. Masamune, in ref. [1c], p. 239: f) I. Paterson, in ref. [1c], p. 301; g) A. S. Franklin, I. Paterson, Contemp. Org. Synth. 1994, 1, 317; h) M. Braun in Stereoselective Synthesis. (Houben-Weyl), Vol. E21/3 (Eds.: G. Helmchen, R. W. Hoffmann, J. Mulzer, E. Schaumann), Thieme, Stuttgart, 1996, p. 1603.
10. Extensive list of chiral auxiliaries: a) A.-ur Rahman, Z. Shah, Stereoselective Synthesis in Organic Chemistry, Springer, Berlin, 1993; b) J. Seyden-Penne, Chiral Auxiliaries and Ligands in Asymmetric Synthesis, Wiley, New York, 1995; c) D. J. Ager, I. Prakash, D. R. Schaad, Chem Rev. 1996, 96, 835.
11. Extensive list of chiral auxiliaries: a) A.-ur Rahman, Z. Shah, Stereoselective Synthesis in Organic Chemistry, Springer, Berlin, 1993; b) J. Seyden-Penne, Chiral Auxiliaries and Ligands in Asymmetric Synthesis, Wiley, New York, 1995; c) D. J. Ager, I. Prakash, D. R. Schaad, Chem Rev. 1996, 96, 835.
12. Extensive list of chiral auxiliaries: a) A.-ur Rahman, Z. Shah, Stereoselective Synthesis in Organic Chemistry, Springer, Berlin, 1993; b) J. Seyden-Penne, Chiral Auxiliaries and Ligands in Asymmetric Synthesis, Wiley, New York, 1995; c) D. J. Ager, I. Prakash, D. R. Schaad, Chem Rev. 1996, 96, 835.
13. S. Hanessian, Total Synthesis of Natural Products: The Chiron Approach, Pergamon, Oxford, 1983.
14. a) C. H. Heathcock; M. C. Pirrung, C. T. Buse, J. P. Hagen, S. D. Young, J. E. Sohn, J. Am. Chem. Soc. 1979, 101, 7077;
15. b) C. H. Heathcock, M. C., Pirrung, J. Lampe, C. T. Buse, S. D. Young, J. Org. Chem. 1981, 46, 2290;
16. c) N. A. Van Draanen, S. Arseniyadis, M. T. Crimmins, C. H. Heathcock, ibid. 1991, 56, 2499;
17. d) S. Masamune, SK. A. Ali, D. L. Snitman, D. S. Garvey, Angew. Chem. 1980, 92, 573; Angew. Chem. Int. Ed. Engl. 1980, 19, 557:
18. d) S. Masamune, SK. A. Ali, D. L. Snitman, D. S. Garvey, Angew. Chem. 1980, 92, 573; Angew. Chem. Int. Ed. Engl. 1980, 19, 557:
19. e) S. Masamune, W. Choy, F. A. L. Kerdesky, B. Imperiali, J. Am. Chem. Soc. 1981, 103, 1566;
20. f) C. Siegel, E. R. Thornton, ibid. 1989, 111, 5722;
21. g) B. M. Trost, H. Urabe, J. Org. Chem. 1990, 55, 3982;
22. h) C. H. Heathcock, C. T. White, J. J. Morrison, D. VanDerveer, ibid, 1981, 46, 1296;
23. i) D. A. Evans, J. V. Nelson, E. Vogel, T. R. Taber, J. Am. Chem. Soc. 1981, 103, 3099;
24. j) B. R. Lagu, H. M. Crane, D. C. Liotta, J. Org. Chem. 1993, 55, 4191;
25. k) S. Figueras, R. Martín, P. Romea, F. Urpí, J. Vilarrasa, Tetrahedron Lett. 1997, 38, 1637.
26. a) C. H. Heathcock, C. T. Buse, W. A. Kleschick, M. C. Pirrung, J. E. Sohn, J. Lampe, J. Org. Chem. 1980, 45, 1066;
27. b) C. H. Heathcock, S. D. Young, J. P. Hagen, M. C. Pirrung, C. T. While, D. Vanderveer, ibid. 1980, 45, 3846.
28. For a detailed information on this topic, see: a) M. Braun, Angew. Chem. 1987, 99, 24; Angew. Chem. Int. Ed. Engl. 1987, 26, 24; b) M. Braun in Advances in Carbanion Chemistry, Vol. 1 (Ed.: V. Snieckus), Jai, London, 1992, p. 177.
29. For a detailed information on this topic, see: a) M. Braun, Angew. Chem. 1987, 99, 24; Angew. Chem. Int. Ed. Engl. 1987, 26, 24; b) M. Braun in Advances in Carbanion Chemistry, Vol. 1 (Ed.: V. Snieckus), Jai, London, 1992, p. 177.
30. For a detailed information on this topic, see: a) M. Braun, Angew. Chem. 1987, 99, 24; Angew. Chem. Int. Ed. Engl. 1987, 26, 24; b) M. Braun in Advances in Carbanion Chemistry, Vol. 1 (Ed.: V. Snieckus), Jai, London, 1992, p. 177.
31. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
32. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
33. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
34. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
35. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
36. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
37. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; c) A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
38. Aldol reactions of achiral methyl ketones with achiral aldehydes on use of chiral boron reagents: a) I. Paterson, J. M. Goodman, Tetrahedron Lett. 1989, 30, 997; b) P. V. Ramachandran, W. Xu, H. C. Brown, Tetrahedron Lett. 1996, 37, 4911; A. Bernardi, C. Gennari, J. M. Goodman, I. Paterson, Tetrahedron Asymmetry 1995, 6, 2613; on use of chiral titanium reagents: d) R. O. Duthaler, P. Herold, W. Lottenbach, K. Oertle; M. Riediker, Angew. Chem. 1989, 101, 490; Angew. Chem. Int. Ed. Engl. 1989, 28, 495; on use of chiral palladium(II) reagents: e) M. Sodeoka, R. Tokunoh, F. Miyazaki, E. Hagiwara, M. Shibasaki, Synlett 1997, 463; on use of external chiral catalysts: f) K. J. Hale, S. Manaviazar in Advanced Asymmetric Synthesis, Vol. 2 (Ed.: G.-R. Stephenson), Chapman and Hall, London, 1996, p. 27; g) T. Mukaiyama, Aldrichimica Acta 1996, 29, 59.
39. Recent examples from chiral acetate imide enolates: a) K. Otsuka, T. Ishizuka, K. Kimura, T. Kunieda, Chem. Pharm. Bull. 1994, 42, 748; b) T.-H. Yan, A.-W. Hung, H.-C. Lee, C. S. Chang, W.-H. Liu, J. Org. Chem. 1995, 60, 3301; c) T. H. Van, A.-W. Hung, H.-C. Lee, C. S. Chang, ibid. 1994, 59, 8187; from chiral N-acetyl sultam enolates: d) W. O. Oppolzer, C. Starkemmann, Tetrahedron Lett. 1992, 33, 2139; from Fisher carbene enolates: e) T. S. Powers, Y. Shi, K. J. Wilson, W. D. Wolff, J. Org. Chem. 1994, 59, 6882.
40. Recent examples from chiral acetate imide enolates: a) K. Otsuka, T. Ishizuka, K. Kimura, T. Kunieda, Chem. Pharm. Bull. 1994, 42, 748; b) T.-H. Yan, A.-W. Hung, H.-C. Lee, C. S. Chang, W.-H. Liu, J. Org. Chem. 1995, 60, 3301; c) T. H. Van, A.-W. Hung, H.-C. Lee, C. S. Chang, ibid. 1994, 59, 8187; from chiral N-acetyl sultam enolates: d) W. O. Oppolzer, C. Starkemmann, Tetrahedron Lett. 1992, 33, 2139; from Fisher carbene enolates: e) T. S. Powers, Y. Shi, K. J. Wilson, W. D. Wolff, J. Org. Chem. 1994, 59, 6882.
41. Recent examples from chiral acetate imide enolates: a) K. Otsuka, T. Ishizuka, K. Kimura, T. Kunieda, Chem. Pharm. Bull. 1994, 42, 748; b) T.-H. Yan, A.-W. Hung, H.-C. Lee, C. S. Chang, W.-H. Liu, J. Org. Chem. 1995, 60, 3301; c) T. H. Van, A.-W. Hung, H.-C. Lee, C. S. Chang, ibid. 1994, 59, 8187; from chiral N-acetyl sultam enolates: d) W. O. Oppolzer, C. Starkemmann, Tetrahedron Lett. 1992, 33, 2139; from Fisher carbene enolates: e) T. S. Powers, Y. Shi, K. J. Wilson, W. D. Wolff, J. Org. Chem. 1994, 59, 6882.
42. Recent examples from chiral acetate imide enolates: a) K. Otsuka, T. Ishizuka, K. Kimura, T. Kunieda, Chem. Pharm. Bull. 1994, 42, 748; b) T.-H. Yan, A.-W. Hung, H.-C. Lee, C. S. Chang, W.-H. Liu, J. Org. Chem. 1995, 60, 3301; c) T. H. Van, A.-W. Hung, H.-C. Lee, C. S. Chang, ibid. 1994, 59, 8187; from chiral N-acetyl sultam enolates: d) W. O. Oppolzer, C. Starkemmann, Tetrahedron Lett. 1992, 33, 2139; from Fisher carbene enolates: e) T. S. Powers, Y. Shi, K. J. Wilson, W. D. Wolff, J. Org. Chem. 1994, 59, 6882.
43. Recent examples from chiral acetate imide enolates: a) K. Otsuka, T. Ishizuka, K. Kimura, T. Kunieda, Chem. Pharm. Bull. 1994, 42, 748; b) T.-H. Yan, A.-W. Hung, H.-C. Lee, C. S. Chang, W.-H. Liu, J. Org. Chem. 1995, 60, 3301; c) T. H. Van, A.-W. Hung, H.-C. Lee, C. S. Chang, ibid. 1994, 59, 8187; from chiral N-acetyl sultam enolates: d) W. O. Oppolzer, C. Starkemmann, Tetrahedron Lett. 1992, 33, 2139; from Fisher carbene enolates: e) T. S. Powers, Y. Shi, K. J. Wilson, W. D. Wolff, J. Org. Chem. 1994, 59, 6882.
44. a) C. Palomo, M. Oiarbide, A. Gonzalez, J. M. García, F. Berree, A. Linden, Tetrahedron Lett. 1996, 37, 6931;
45. b) C. Palomo, F. Berree, A. Linden, J. M. Villalgordo, J. Chem. Soc. Chem. Commun. 1994, 1961.
46. For an earlier camphor-based ester acetate aldol approach exploiting this concept in another way, see G. Helmchen, U. Leikauf, I. Tauferknöpfel, Angew. Chem. 1985, 97, 874; Angew. Chem. Int. Ed. Engl. 1985, 24, 874.
47. For an earlier camphor-based ester acetate aldol approach exploiting this concept in another way, see G. Helmchen, U. Leikauf, I. Tauferknöpfel, Angew. Chem. 1985, 97, 874; Angew. Chem. Int. Ed. Engl. 1985, 24, 874.
48. Review on camphor-based chiral auxilaries: W. Oppolzer, Tetrahedron 1987, 43, 1969.
49. H. E. Zimmerman, M. D. Traxler, J. Am. Chem. Soc. 1957, 79, 1920.
50. M. Kagawa, Chem. Pharm. Bull. 1959, 7, 306.
51. a) M. M. Midland, J. Org. Chem. 1975, 40, 2250;
52. b) M. M. Midland, J. I. McLoughlin, R. T. Werley, Jr., Org. Synth. Coll. 1993, Vol 8, p 391.
53. [20]
54. [20]
55. [20]
56. J. M. Aizpurua, C. Palomo, A. L. Palomo, Can. J. Chem. 1984, 62, 336.
57. [7d]].
58. T. Imamoto, N. Takiyama, K. Nakamura, T. Hatajima, Y. Kamiya, J. Am. Chem. Soc. 1989, 111, 4392.
59. Every attempt at attacking the carbonyl group of the corresponding aldols with both lithium and Grignard reagents led to unsatisfactory results.
60. Crystallographic data (excluding structure factors) for the structures 5, 7g, and 13 have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-100315. Copies of the data can be obtained free of charge on application to: CCDC, 12 Union Road, Cambridge CB21EZ, UK (fax: int. code + (44) 1223-336033; e-mail: deposit@cheirjcrys.cam.ac.uk).