Preference for axial N-alkylation of tetrahydro-1,3-oxazines and hexahydropyrimidines: Manifestation of a kinetic anomeric effect

Journal of Organic Chemistry

Volumn 65, Issue 3, 2000, Pages 889-894

  Berges, David A ^a   Fan, Jianmei ^a   Devinck, Sylvie ^a   Mower, Kendall ^a  

^a Brigham Young University   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

1,3 OXAZINE DERIVATIVE; HETEROCYCLIC COMPOUND; PYRIMIDINE DERIVATIVE;

ALKYLATION; ARTICLE; CARBON NUCLEAR MAGNETIC RESONANCE; CHEMICAL REACTION; CHEMICAL STRUCTURE; KINETICS; PROTON NUCLEAR MAGNETIC RESONANCE;

EID: 0033952241     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo991752i     Document Type: Article

References (26)

1. For reviews, see: (a) Anomeric Effect, Origin and Consequences; Szarek, W. A., Horton, D., Eds.; ACS Symposium Series 87; American Chemical Society: Washington, DC, 1979. (b) Kirby, A. J. The Anomeric Effect and Related Stereoelectronic Effects at Oxygen; Springer-Verlag: New York, 1983. (c) Tvaroška, I.; Bleha, T. Adv. Carbohydr. Chem. Biochem. 1989, 47, 45-123. (d) The Anomeric Effect and Associated Stereoelectronic Effects; Thatcher, G. R. J., Ed.; ACS Symposium Series 593; American Chemical Society: Washington, DC, 1993. (e) Graczyk, P. P.; Mikołajczyk, M. Top. Stereochem. 1994, 21, 159-349. (f) Juaristi, E.; Cuevas, G. The Anomeric Effect; CRC: Boca Raton, FL, 1995.
2. For reviews, see: (a) Anomeric Effect, Origin and Consequences; Szarek, W. A., Horton, D., Eds.; ACS Symposium Series 87; American Chemical Society: Washington, DC, 1979. (b) Kirby, A. J. The Anomeric Effect and Related Stereoelectronic Effects at Oxygen; Springer-Verlag: New York, 1983. (c) Tvaroška, I.; Bleha, T. Adv. Carbohydr. Chem. Biochem. 1989, 47, 45-123. (d) The Anomeric Effect and Associated Stereoelectronic Effects; Thatcher, G. R. J., Ed.; ACS Symposium Series 593; American Chemical Society: Washington, DC, 1993. (e) Graczyk, P. P.; Mikołajczyk, M. Top. Stereochem. 1994, 21, 159-349. (f) Juaristi, E.; Cuevas, G. The Anomeric Effect; CRC: Boca Raton, FL, 1995.
3. For reviews, see: (a) Anomeric Effect, Origin and Consequences; Szarek, W. A., Horton, D., Eds.; ACS Symposium Series 87; American Chemical Society: Washington, DC, 1979. (b) Kirby, A. J. The Anomeric Effect and Related Stereoelectronic Effects at Oxygen; Springer-Verlag: New York, 1983. (c) Tvaroška, I.; Bleha, T. Adv. Carbohydr. Chem. Biochem. 1989, 47, 45-123. (d) The Anomeric Effect and Associated Stereoelectronic Effects; Thatcher, G. R. J., Ed.; ACS Symposium Series 593; American Chemical Society: Washington, DC, 1993. (e) Graczyk, P. P.; Mikołajczyk, M. Top. Stereochem. 1994, 21, 159-349. (f) Juaristi, E.; Cuevas, G. The Anomeric Effect; CRC: Boca Raton, FL, 1995.
4. For reviews, see: (a) Anomeric Effect, Origin and Consequences; Szarek, W. A., Horton, D., Eds.; ACS Symposium Series 87; American Chemical Society: Washington, DC, 1979. (b) Kirby, A. J. The Anomeric Effect and Related Stereoelectronic Effects at Oxygen; Springer-Verlag: New York, 1983. (c) Tvaroška, I.; Bleha, T. Adv. Carbohydr. Chem. Biochem. 1989, 47, 45-123. (d) The Anomeric Effect and Associated Stereoelectronic Effects; Thatcher, G. R. J., Ed.; ACS Symposium Series 593; American Chemical Society: Washington, DC, 1993. (e) Graczyk, P. P.; Mikołajczyk, M. Top. Stereochem. 1994, 21, 159-349. (f) Juaristi, E.; Cuevas, G. The Anomeric Effect; CRC: Boca Raton, FL, 1995.
5. For reviews, see: (a) Anomeric Effect, Origin and Consequences; Szarek, W. A., Horton, D., Eds.; ACS Symposium Series 87; American Chemical Society: Washington, DC, 1979. (b) Kirby, A. J. The Anomeric Effect and Related Stereoelectronic Effects at Oxygen; Springer-Verlag: New York, 1983. (c) Tvaroška, I.; Bleha, T. Adv. Carbohydr. Chem. Biochem. 1989, 47, 45-123. (d) The Anomeric Effect and Associated Stereoelectronic Effects; Thatcher, G. R. J., Ed.; ACS Symposium Series 593; American Chemical Society: Washington, DC, 1993. (e) Graczyk, P. P.; Mikołajczyk, M. Top. Stereochem. 1994, 21, 159-349. (f) Juaristi, E.; Cuevas, G. The Anomeric Effect; CRC: Boca Raton, FL, 1995.
6. For reviews, see: (a) Anomeric Effect, Origin and Consequences; Szarek, W. A., Horton, D., Eds.; ACS Symposium Series 87; American Chemical Society: Washington, DC, 1979. (b) Kirby, A. J. The Anomeric Effect and Related Stereoelectronic Effects at Oxygen; Springer-Verlag: New York, 1983. (c) Tvaroška, I.; Bleha, T. Adv. Carbohydr. Chem. Biochem. 1989, 47, 45-123. (d) The Anomeric Effect and Associated Stereoelectronic Effects; Thatcher, G. R. J., Ed.; ACS Symposium Series 593; American Chemical Society: Washington, DC, 1993. (e) Graczyk, P. P.; Mikołajczyk, M. Top. Stereochem. 1994, 21, 159-349. (f) Juaristi, E.; Cuevas, G. The Anomeric Effect; CRC: Boca Raton, FL, 1995.
7. Romers, C.; Altona, C.; Buys, H. R.; Havinga, E. Top. Stereochem. 1969, 4, 39-97.
8. Deslongchamps, P. Stereoelectronic Effects in Organic Chemistry; Pergamon: New York, 1983; p 31.
9. Berges, D. A.; Fan, J.; Devinck, S.; Liu, N.; Dalley, N. K. Tetrahedron 1999, 55, 6759-6770.
10. 6
11. 1H three-bond coupling constants in bicyclic azasugars follows very well an empirical method developed for pyranose rings: Altona, C.; Haasnoot, C. A. G. Org. Magn. Reson. 1980, 13, 417-429.
12. 3e in 2α and 2β, respectively). The high-field appearance of this proton has been reported previously: Booth, H.; Lemieux, R. U. Can. J. Chem. 1971, 49, 777-788.
13. To have kinetic control involving intermediate 10, the transition states for cyclization cannot be productlike since 2β is more stable than 2α. Therefore, they must resemble 10, and there should be little difference in the rates of formation of 2α and 2β if 10 is their precursor.
14. 3e protons of the products is apparent at the later times in Figure 1.
15. 13C NMR observing peaks at approximately δ 25.5 and 25.4 for the tetrahydrooxazine carbon at ring position 5 for the two epimers.
16. 1H NMR signals overlapped with those of other species.
17. -1 and T = 298 K).
18. The fact that the conformations of the products 2α and 2β resemble those of conformational states 8α*-1 and 8β*-1 does not necessarily mean that these conformational states are precursors to the products since any other conformations of the products arising directly from cyclization may rapidly deprotonate and flip a ring with concomitant nitrogen inversion to give the favored conformations. The process of rapid flipping has been observed with the related compounds and will be reported separately.
19. It is likely that such an anomeric effect would produce more stabilization for the transition state than for the ground state because the former involves a sharing of charge and the latter a separation of charge.
20. Details about these NMR assignments and conformational and configurational equilibria will be published separately.
21. The rate of conversion of 16β to 16α ought to be about 9 times that of the reverse reaction, which reaches equilibrium over about 3 days. Therefore, conversion of 16β to 16α is a relatively slow process compared with the rate of formation of 16α, and 16β cannot be a significant source of 16α.
22. Kent, P. W.; Young, R. C. Tetrahedron 1971, 27, 4057-4064.
23. Hutching, R. O.; Maryanoff, B. E. J. Org. Chem. 1972, 37, 1829-1830.
24. 13C NMR signals. In these cases, definitive assignments could not be made.
25. 4OH caused a change in chemical shift, which separated some overlapping signals and allowed coupling constants to be determined.
26. 4OH added.