Asymmetric synthesis of 2,3-disubstituted oxepanes via acetalization- cyclization of an enantioenriched functionalized allylsilane with aldehydes

Chemical Communications

Volumn , Issue 24, 1999, Pages 2537-2538

  Suginome, Michinori ^a   Iwanami, Taisuke ^a   Ito, Yoshihiko ^a  

^a KYOTO UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

ALDEHYDE DERIVATIVE; OXEPANE DERIVATIVE; SILANE DERIVATIVE;

ACETYLATION; ARTICLE; CHEMICAL MODIFICATION; CHEMICAL REACTION; CYCLIZATION; REACTION ANALYSIS; STEREOCHEMISTRY; SYNTHESIS;

EID: 0033592996     PISSN: 13597345     EISSN: None     Source Type: Journal    
DOI: 10.1039/a908603j     Document Type: Article

References (16)

1. For the five-membered ring formation, see: P. Mohr, Tetrahedron Lett., 1993, 34, 6251; T. Oriyama, A. Ishiwata, T. Sano, T. Matsuda, M. Takahashi and K. Koga, Tetrahedron Lett., 1995, 36, 5581; T. Sano and T. Oriyama, Synlett, 1997, 716.
2. For the five-membered ring formation, see: P. Mohr, Tetrahedron Lett., 1993, 34, 6251; T. Oriyama, A. Ishiwata, T. Sano, T. Matsuda, M. Takahashi and K. Koga, Tetrahedron Lett., 1995, 36, 5581; T. Sano and T. Oriyama, Synlett, 1997, 716.
3. For the five-membered ring formation, see: P. Mohr, Tetrahedron Lett., 1993, 34, 6251; T. Oriyama, A. Ishiwata, T. Sano, T. Matsuda, M. Takahashi and K. Koga, Tetrahedron Lett., 1995, 36, 5581; T. Sano and T. Oriyama, Synlett, 1997, 716.
4. For the six-membered ring formation, see: I. E. Markó and A. Mekhalfia, Tetrahedron Lett., 1992, 33, 1799; I. E. Markó and D. J. Bayston, Tetrahedron, 1994, 50, 7141; I. E. Markó, M. Bailey, F. Murphy, J. P. Declercq, B. Tinant, J. Feneau-Dupont, A. Krief and W. Dumont, Synlett, 1995, 123.
5. For the six-membered ring formation, see: I. E. Markó and A. Mekhalfia, Tetrahedron Lett., 1992, 33, 1799; I. E. Markó and D. J. Bayston, Tetrahedron, 1994, 50, 7141; I. E. Markó, M. Bailey, F. Murphy, J. P. Declercq, B. Tinant, J. Feneau-Dupont, A. Krief and W. Dumont, Synlett, 1995, 123.
6. For the six-membered ring formation, see: I. E. Markó and A. Mekhalfia, Tetrahedron Lett., 1992, 33, 1799; I. E. Markó and D. J. Bayston, Tetrahedron, 1994, 50, 7141; I. E. Markó, M. Bailey, F. Murphy, J. P. Declercq, B. Tinant, J. Feneau-Dupont, A. Krief and W. Dumont, Synlett, 1995, 123.
7. M. Suginome, T. Iwanami and Y. Ito, J. Org. Chem., 1998, 63, 6096.
8. For a review of the reactions of chiral allylsilanes, see: C. E. Masse and J. S. Panek, Chem. Rev., 1995, 95, 1293.
9. K. Matsumura, S. Hashiguchi, T. Ikariya and R. Noyori, J. Am. Chem. Soc., 1997, 119, 8738; K.-J. Haack, S. Hashiguchi, A. Fujii, T. Ikariya and R. Noyori, Angew. Chem., Int. Ed. Engl., 1997, 36, 285. The absolute configuration (S) of 3 was assigned by an analogy with these reports.
10. K. Matsumura, S. Hashiguchi, T. Ikariya and R. Noyori, J. Am. Chem. Soc., 1997, 119, 8738; K.-J. Haack, S. Hashiguchi, A. Fujii, T. Ikariya and R. Noyori, Angew. Chem., Int. Ed. Engl., 1997, 36, 285. The absolute configuration (S) of 3 was assigned by an analogy with these reports.
11. M. Suginome, A. Matsumoto and Y. Ito, J. Am. Chem. Soc., 1996, 118, 3061; M. Suginome, T. Iwanami, A. Matsumoto and Y. Ito, Tetrahedron: Asymmetry, 1997, 8, 859.
12. M. Suginome, A. Matsumoto and Y. Ito, J. Am. Chem. Soc., 1996, 118, 3061; M. Suginome, T. Iwanami, A. Matsumoto and Y. Ito, Tetrahedron: Asymmetry, 1997, 8, 859.
13. D -8.38 (c 3.1, benzene).
14. 1H NMR coupling constant between the 2- and 3-protons in the ring. Compound 6a exhibited a coupling constant of 9.6 Hz, whereas that for trans- and cis-2-(phenylsulfonylmethyl)-3-(phenylmethyl)oxepane were reported as 8.5 and 2.6 Hz, respectively. See: P. L. López-Tudanca, K. Jones and P. Brownbridge, Tetrahedron Lett., 1991, 32, 2261.
15. 2O). The 3,5-dinitrophenylanilides were subjected to chiral HPLC with Sumichiral OA columns indicated below [compound, column, solvent (a ratio of hexanes-1,2-dichloroethane-ethanol)]: (6b, OA-4400, 50:15:1); (6c, OA-4500 × 3, 15:15:1); (6d, OA-4400, 15:5:1); (6e, OA-4900, 15:5:1); (6f, OA-4500, 15:5:1); (6g, OA-4600, 15:5:1). The absolute configurations were assigned by analogy with the stereochemical outcome for the six-membered ring formation reported previously. See ref. 3.
16. The slight decrease in the enantiomeric excesses may be attributed to a minor contribution of 'syn attack' of the electrophiles on the allylsilane moieties during the cyclization in addition to the normal 'anti attack'. For a discussion on the 'anti' vs. 'syn' attack in the reaction of allylsilanes with electrohiles, see: M. J. C. Bucke, I. Fleming and S. Gil, Tetrahedron Lett., 1992, 33, 4479.