Anionic two-carbon ring expansions of oxabicyclo[2.2.1]heptenes and oxabicyclo[4.2.1]nonenes

Organic Letters

Volumn 1, Issue 8, 1999, Pages 1161-1163

  Rainier, Jon D ^a   Xu, Qing ^a  

^a University of Arizona   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0000857122     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol990795i     Document Type: Article

References (22)

1. Rainier, J. D.; Xu, Q. Org. Lett. 1999, 1, 27-29.
2. For a recent example of a β-keto ester - Michael addition reaction which leads to bicyclic ring systems see: Aoyagi, K.; Nakamura, H.; Yamamoto, Y. J. Org. Chem. 1999, 64, 4148-4151.
3. For related ring expansions see: (a) Xie, Z.-F.; Sakai, K. J. Org. Chem. 1990, 55, 820-826.
4. (b) Lavoisier-Gallo, T.; Charonnet, E.; Rodriguez, J. J. Org. Chem. 1998, 63, 900-902.
5. We envision that 2 and 3 (Table 1) will be useful in the formation of medium-sized rings. For example, oxidative carbon-carbon bond fragmentation would lead to the corresponding oxepanes. Ketal hydrolysis would result in the synthesis of the corresponding cyclooctenones.
6. (a) Chenna, A.; Donnelly, J.; McCullough, K. J.; Proctor, G. R.; Redpath, J. J. Chem. Soc., Perkin Trans. 1 1990, 261-265.
7. (b) Frew, A. J.; Proctor, G. R. J. Chem. Soc., Perkin Trans. I 1980 1245-1250.
8. (c) Frew, A. J.; Proctor, G. R. J. Chem. Soc., Perkin Trans. I 1980, 1251-1256.
9. For representative examples of this family see: (a) Barrero, A. F.; Oltra, J. E.; Raslan, D. S.; Saude, D. A. J. Nat. Prod. 1999, 62, 726-729.
10. (b) Baruah, N. C.; Sharma, R. P.; Madhusudanan, K. P.; Thyagarajan, G.; Herz, W. Murari, R. J. Org. Chem. 1979, 44, 1831-1835.
11. (c) Raffauf, R. F.; Huang, P.-K. C.; Le Quesne, P. W.; Levery, S. B.; Brennan, T. F. J. Am. Chem. Soc. 1975, 97, 6884-6886.
12. For the total synthesis of heliangolides see: (a) Boeckman, R. K., Jr.; Yoon, S. K.; Heckendorn, D. K. J. Am. Chem. Soc. 1991, 113, 9682-9684.
13. (b) Takao, K.; Ochiai, H.; Yoshida, K.; Hashizuka, T.; Koshimura, H.; Tadano, K.; Ogawa, S. J. Org. Chem. 1995, 60, 8179-8193.
14. Bernardelli, P.; Paquette, L. A. Heterocycles 1998, 49, 531-556.
15. For the total synthesis of oxygenated cembranoids see: (a) MacMillan, D. W. C.; Overman, L. E. J. Am. Chem. Soc. 1995, 117, 10391-10392.
16. (b) Nicolaou, K. C.; Xu, J. Y.; Kim, S.; Pfefferkorn, J.; Ohshima, T.; Vourloumis, D.; Hosokawa, S. J. Am. Chem. Soc. 1998, 120, 8661-8673.
17. (c) Nicolaou, K. C.; Ohshima, T.; Hosokawa, S.; van Delft, F. L.; Vourloumis, D.; Xu, J. Y.; Pfefferkorn, J.; Kim, S. J. Am. Chem. Soc. 1998, 120, 8674-8680.
18. (d) Chen, X.-T.; Zhou, B.; Bhattacharya, S. K.; Gutteridge, C. E.; Pettus, T. R. R.; Danishefsky, S. J. Angew. Chem., Int. Ed. 1998, 37, 185-187.
19. The relative stereochemistry at C-4 in 2 and 3 was determined by first converting each of them into the corresponding enol acetate and then identifying the expected NOESY cross-peaks.
20. 5b
21. 2O.
22. 3, R′ = H) is much less efficient in the two-carbon ring expansion reaction (21% yield using DMAD).