Glycals as Ambident Electrophiles Towards Organometallic Nucleophiles. Stereoselective Synthesis of C(3)-Branched Carbohydrates

Synlett

Volumn 1996, Issue 9, 1996, Pages 856-858

  Thorn, Simon N ^a   Gallagher, Timothy ^a  

^a UNIVERSITY OF BRISTOL   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001252633     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1996-5600     Document Type: Article

References (15)

1. (a) Orsini, F.; Pelizzoni, F. Carbohydr. Res. 1993, 243, 183;
2. (b) Dunkerton, L.V.; Euske, J.M.; Serino, A.J. Carbohydr. Res. 1987, 171, 89;
3. (c) Thorn, S. N.; Gallagher, T. Synlett 1996, 185.
4. Knochel, P.; Singer, R. D. Chem. Rev. 1993, 93, 2117.
5. Yeh, M. C. P.; Knochel, P. Tetrahedron Lett. 1988, 29, 2395
6. 4) and concentrated in vacuo. The product was purified by chromatography (eluting with 25 % EtOAc - 75 % hexanes) to give adduct (5) in 91 % yield as a pale yellow oil.
7. 2Cu(CN)ZnI to (1a) were also unsuccessful.
8. 1H NMR data for 3-substituted glycals see Fraser-Reid, B.; Carthy, B. J.; Radatus, B. Tetrahedron 1972, 28, 2741; Greenspoon, N.; Keinan, E. J. Org. Chem. 1988, 53, 3723; Marco-Contelles, J. L.; Fernández, C.; Gómez, A.; Martín-León, N. Tetrahedron Lett. 1990, 31, 1467.
9. 1H NMR data for 3-substituted glycals see Fraser-Reid, B.; Carthy, B. J.; Radatus, B. Tetrahedron 1972, 28, 2741; Greenspoon, N.; Keinan, E. J. Org. Chem. 1988, 53, 3723; Marco-Contelles, J. L.; Fernández, C.; Gómez, A.; Martín-León, N. Tetrahedron Lett. 1990, 31, 1467.
10. 1H NMR data for 3-substituted glycals see Fraser-Reid, B.; Carthy, B. J.; Radatus, B. Tetrahedron 1972, 28, 2741; Greenspoon, N.; Keinan, E. J. Org. Chem. 1988, 53, 3723; Marco-Contelles, J. L.; Fernández, C.; Gómez, A.; Martín-León, N. Tetrahedron Lett. 1990, 31, 1467.
11. 1H NMR analysis was consistent with the stereochemical assignments shown. See also Kelly, M. J.; Roberts, S. M. J. Chem. Soc., Perkin Trans. 1 1991, 787.
12. The intermediacy of a Ferrier rearrangement product/oxonium species is likely in the systems discussed in this paper. In support of this, substitution of 3,4,6-tri-O-acetyl-D-allal (19) led to adduct (5) in 59 % isolated yield, a process that proceeds with inversion of configuration at C(3). (Matrix Presented)
13. Mitsunobu, O.; Yoshida, M.; Takayi, M.; Kubo, K.; Maruyama, S.; Satoh, I.; Iwami, H. Chemistry Lett. 1989, 809.
14. Ogihara, T.; Mitsunobu, O. Tetrahedron Lett. 1983, 24, 3505.
15. Dorgan, B. J.; Jackson, R. F. W. Synlett, 1996, 859.