Synthetic approach to Kdo glycosides via exo-glycal epoxides and rationalization of the stereochemical outcome

Journal of Carbohydrate Chemistry

Volumn 17, Issue 8, 1998, Pages 1269-1281

  Lay, Luigi ^a   Nicotra, Francesco ^a   Panza, Luigi ^a   Russo, Giovanni ^a   Sello, Guido ^a  

^a Ctro Stud Sostanze Organiche N   (Italy)

Author keywords

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Indexed keywords

EID: 0032328604     PISSN: 07328303     EISSN: None     Source Type: Journal    
DOI: 10.1080/07328309808001899     Document Type: Article

References (16)

1. F. M. Unger, Adv. Carbohydr. Chem. Biochem., 38, 323, (1981).
2. See e.g. a) F. J. Lopez-Herrera and F. Sarabia-Garcia, Tetrahedron, 53, 3325 (1997) and referenced cited therein;
3. b) H. Sekljic, N. Wimmer, A. Hofinger, H. Brade and P. Kosma, J. Chem. Soc., Perkin Trans. 1, 1973 (1997) and references cited therein.
4. A Haudrechy and P. Sinaÿ, J. Org. Chem., 57, 4142 (1992).
5. F. Nicotra, L. Panza and G. Russo, Tetrahedron Lett., 32, 4035 (1991).
6. O. T. Schmidt, Methods Carbohydr. Chem., 2, 318 (1963).
7. D. J. Ager, Synthesis, 384 (1984).
8. 1H NMR spectrum of this byproduct is consistent with the structure reported in the following figure and could originate from a nucleophilic attack of a methyl group on the C-1 of the lactone followed by Tebbe olefination of the resulting hemiketal. (equation presented)
9. R. Csuk and B. I. Glänzer, Tetrahedron, 47, 1655, (1991).
10. a) R. W. Murray and R. J. Jeyaraman, J. Org. Chem., 50, 2847 (1985);
11. b) W. Adam, J. Bialas and L. Hadjiarapoglou, Chem. Ber., 2377 (1991)
12. S. Horito, M. Tada and H. Hashimoto, Chem. Lett., 117 (1991).
13. AMI in MOPAC 6.0, 1990, QCPE n. 527, Indiana University, Bloomington, IN, USA.
14. 2 as Lewis acid, it was considered a sufficient approximation.
15. 2 included), showing their conversion to a common carbocationic intermediate.
16. It is obvious that, when using less reactive alcohols, the epoxide ratio will not completely control the products ratio and the mechanism is expected to pass in part through the carbocation intermediate.