AgOTF-promoted conversion of 4,5-epoxy-1-bromide into tetrahydropyran ring

Chemistry Letters

Volumn , Issue 5, 1996, Pages 341-342

  Hayashi, Nobuyuki ^a   Fujiwara, Kenshu ^a   Murai, Akio ^a  

^a HOKKAIDO UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0030489899     PISSN: 03667022     EISSN: None     Source Type: Journal    
DOI: 10.1246/cl.1996.341     Document Type: Article

References (14)

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3. b) K. C. Nicolaou, C. V. C. Prasad, P. K. Somers, and C.-K. Hwang, J. Am. Chem. Soc., 111, 5335 (1989).
4. c) T. Suzuki, O. Sato, and M. Hirama, Tetrahedron Lett., 31, 4747 (1990).
5. d) C. Mukai, Y. Ikeda, Y. Sugimoto, and M. Hanaoka, Tetrahedron Lett., 35, 2179 (1994).
6. e) C. Mukai, Y. Sugimoto, Y. Ikeda, and M. Hanaoka, Tetrahedron Lett., 35, 2183 (1994).
7. A concerted process might be alternatively assumed on this reaction mechanism as shown in Scheme 3. However, the concept of the bridged oxonium ion seems to explain the experimental results more facilely. Therefore, in this report, the bridged oxoniumion pathway was adopted. The true reaction mechanism could not be clarified from the obtained experimental results. equation presented Scheme 3.
8. E. Alvarez, M. T. Diaz, R. Perez, J. L. Ravelo, A. Regueiro, J. A. Vera, D. Zurita, and J. D. Martin, J. Org. Chem., 59, 2848 (1994).
9. a) T. Nakata, G. Schmid, B. Vranesic, M. Okigawa, T. Smith-Palmer, and Y. Kishi, J. Am. Chem. Soc., 100, 2933 (1978);
10. see also: b) T. Nakata, S. Nomura, and H. Matsukura, Tetrahedron Lett., 37, 213 (1996).
11. c) T. Nakata, S. Nomura, H. Matsukura, and M. Morimoto, Tetrahedron Lett., 37, 217 (1996).
12. AgOTf was used, because it was more soluble in various organic solvents than other silver cation sources.
13. 1R-NMR, IR, and mass spectral data were provided for compounds 7, 8, and 11 after acetylation.
14. The stereochemistry of 11 was determined by the conversion to the acetate of 8 by Mitsunobu reaction.