Mechanistic insights into the factors determining exo-endo selectivity in the Lewis acid-catalyzed Diels-Alder reaction of 1,3-dienes with 2-cycloalkenones

Organic Letters

Volumn 2, Issue 13, 2000, Pages 1927-1929

  Ge, Min ^a   Stoltz, Brian M ^a   Corey, E J ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001115428     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0060026     Document Type: Article

References (15)

1. Stoltz, B. M.; Corey, E. J. Unpublished.
2. For recent reviews, see: (a) Diaz, L. D. J. Braz. Chem. Soc. 1997, 8, 289.
3. (b) Pindur, U.; Lutz, G.; Otto, C. Chem. Rev. 1993, 93, 741.
4. (c) Corey, E. J.; Guzman-Perez, A. Angew. Chem., Int. Ed. 1998, 37, 388.
5. (d) Corey, E. J.; Rohde, J. J. Tetrahedron Lett. 1997, 38, 37.
6. (e) Corey, E. J.; Barnes-Seeman, D.; Lee, T. W. Tetrahedron Lett. 1997, 38, 1699.
7. (a) Angell, E. C.; Fringuelli, F.; Guo, M.; Minuti, L.; Taticchi, A.; Wenkert, E. J. Org. Chem. 1988, 53, 4325.
8. (b) Angell, E. C.; Fringuelli, F.; Minuti, L.; Pizzo, F.; Porter, B.; Taticchi, A.; Wenkert, E. J. Org. Chem. 1986, 51, 2649.
9. See also: Das, J.; Kakushima, M.; Valenta, Z.; Jankowski, K.; Luce, R. Can. J. Chem. 1984, 62, 411.
10. Detailed X-ray crystallographic data are available from the Cambridge Crystallographic Data Center, 12 Union Road, Cambridge CB2 1EZ, U.K.
11. The assignment of structure 3 to the major (exo) adduct from 1 and 2 was also determined unambiguously by X-ray crystallographic analysis (unpublished results of Brian M. Stoltz).
12. 1H NMR NOE measurements with diene 2 (R = allyl) confirmed the nonplanarity of the 1,3-diene moiety, since the terminal olefinic methylene proton which is trans to the OTBS group showed positive NOE enhancement with both the olefinic proton at the other end of the diene (+2.2%) and the peri proton on the benzenoid ring (+2.7%).
13. (a) Singleton, D. A.; Merrigan, S. R.; Beno, B. R.; Houk, K. N. Tetrahedron Lett. 1999, 40, 5817.
14. (b) Garcia, J. I.; Martinez-Merino, V.; Mayoral, J. A.; Salvatella, L. J. Am. Chem. Soc. 1998, 120, 2415.
15. 3, 100 MHz) δ 215.3, 139.4, 114.0, 51.7, 44.6, 40.0, 37.8, 33.9, 27.8, 27.5, 26.6, 26.32, 26.30, 26.2, 26.1, 18.7, 17.1, -3.3, -3.5 ppm; mp 58-59 °C.