Stereoselective synthesis of novel 4,5-epoxy-1,2-oxazin-6-ones and α,β-epoxy-γ-amino acids from β-lithiated oxazolinyloxiranes and nitrones

Organic Letters

Volumn 8, Issue 21, 2006, Pages 4803-4806

  Capriati, Vito ^a   Degennaro, Leonardo ^a   Florio, Saverio ^a   Luisi, Renzo ^a   Punzi, Pasqualina ^a  

^a UNIVERSITY OF BARI   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

AMINO ACID; EPOXIDE; LITHIUM; NITROGEN OXIDE; NITRONES; OXAZINE DERIVATIVE; OXAZOLE DERIVATIVE;

ARTICLE; CHEMISTRY; STEREOISOMERISM; SYNTHESIS;

AMINO ACIDS; EPOXY COMPOUNDS; LITHIUM; NITROGEN OXIDES; OXAZINES; OXAZOLES; STEREOISOMERISM;

EID: 33750304716     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0618609     Document Type: Article

References (34)

1. (a) Cheng, R. P.; Gellman, S. H.; DeGrado, W. F. Chem. Rev. 2001, 101, 3219-3232.
2. (b) Hill, D. J.; Prince, R. B.; Hughes, T. S.; Moore, J. S. Chem. Rev. 2001, 101, 3893-4012.
3. (a) Seebach, D.; Beck, A. K.; Bierbaum, D. J. Chem. Biodiv. 2004, 1, 1111-1239.
4. (b) Hill, D. J.; Mio, M. J.; Prince, R. B.; Hughes, T. S.; Moore, J. S. Chem. Rev. 2001, 101, 3893-4011.
5. (a) Woll, M. G.; Lay, J. R.; Guzei, I. A.; Taylor, S. J. C.; Smith, M. E.; Gellman, S. J. Am. Chem. Soc. 2001, 123, 11077-11078.
6. (b) Martin-Vilà, M.; Muray, E.; Aguado, O. P.; Alvarez-Larena, A.; Branchadell, V.; Minguillòn, C.; Giralt, E.; Ortuno, R. M. Tetrahedron: Asymmetry, 2000, 11, 3569-3584.
7. (c) Aravinda, S.; Ananda, K.; Shamala, N.; Balaram, P. Chem. Eur. J. 2003, 9, 4789-4795.
8. (d) Gnad, F.; Reiser, O. Chem. Rev. 2003, 103, 1603-1623.
9. (a) Wipf, P.; Stephenson, C. R. J. Org. Lett. 2005, 7, 1137-1140.
10. (b) Esposito, A.; Piras, P. P.; Ramazzotti, D.; Taddei, M. Org. Lett. 2001, 3, 3273-3275.
11. (a) Capriati, V.; Degennaro L.; Favia, R.; Florio, S.; Luisi, R. Org. Lett. 2002, 4, 1551-1554.
12. (b) Luisi, R.; Capriati, V.; Degennaro, L.; Florio, S. Org. Lett. 2003, 5, 2723-2726.
13. Capriati, V.; Florio, S.; Luisi, R. Synlett 2005, 9, 1359-1369.
14. Scholz, D.; Billich, A.; Charpiot, B.; Ettmayer, P.; Lehr, P.; Rosenwirth, B.; Schreiner, E.; Gstach, H. J. Med. Chem. 1994, 37, 3079-3089.
15. 1H NMR analysis performed on the crude deblocked 1,2-oxazin-6-ones 6 (see text).
16. For a stereoselective synthesis of optically active 5-isoxazolidin-5-ones and β-amino acids, see: (a) Capriati, V.; Degennaro, L.; Florio, S.; Luisi, R. Eur. J. Org. Chem. 2002, 2961-2969.
17. (b) Luisi, R.; Capriati, V.; Florio, S.; Vista, T. J. Org. Chem. 2003, 68, 9861-9864.
18. CCDC 606445 contains the supplementary crystallographic data for compound 4b. These data can be obtained, free of charge, from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
19. Luisi, R.; Capriati, V.; Degennaro, L.; Florio, S. Tetrahedron 2003, 59, 9713-9718.
20. -1 which is the typical stretching frequency.
21. 1H NMR; over time, the signals of the hydroxylamino forms 5 tend to increase. Under the same conditions, the alkyl-substituted derivatives are mainly present, from the beginning, as hydroxylamino forms.
22. CCDC 606447 contains the supplementary crystallographic data for compound 5f. These data can be obtained, free of charge, from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
23. Such epoxyhydroxyamides are the main products when the reaction is performed with an excess of TFA.
24. CCDC 606446 contains the supplementary crystallographic data for compound 6d. These data can be obtained, free of charge, from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
25. 2/C did not cause any oxirane ring-opening reaction leading, instead, to α,β-epoxy-γ-amino acids 10a,b as the main products.
26. CCDC 606448 contains the supplementary crystallographic for compound 11a. These data can be obtained, free of charge, from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
27. For some examples concerning the easy deprotection of the cumyl group, see: (a) Clayden, J.; Menet, C. J.; Mansfield, D. J. Org. Lett. 2000, 2, 4229-4232.
28. (b) Clayden, J.; Tchabanenko, K.; Yasin, S. A.; Turnbull, M. D. Synlett 2001, 302-304.
29. N-Benzyl nitrones are not useful because of the pronounced acidity of the benzylic hydrogens, which is able to protonate the starting lithiated oxirane.
30. Hydrolysis of 4m furnished the expected epoxy-1,2-oxazinone 6m only in a low yield, the main product being the hydroxyamide 8 (Scheme 1). The formation of this compound, which is currently under investigation, could be explained with a concerted cumene hydroperoxide-type rearrangement involving a reactive delocalized phenonium ion as the intermediate further to an electrophilic aromatic substitution promoted by the π-electrons on the nitrogen atom linked to the cumyl group. See also: Hamann, H.-Y.; Liebscher, Y. J. Org. Chem. 2000, 65, 1873-1876.
31. 3 for at least 24-36 h.
32. 4) occurred; see also: (a) Ram, S.; Ehrenkaufer, R. E. Synthesis 1988, 91-95.
33. (b) Luisi, R.; Capriati, V.; Florio, S.; Vista, T. J. Org. Chem. 2003, 68, 9861-9864.
34. In these cases, in contrast to that observed with spirocyclic compounds 4a-m, there was no equilibration with the corresponding hydroxylamino forms.