On the Inherent Instability of α-Amino α′-Fluoro Ketones. Evidence for Their Transformation to Reactive Oxyvinyliminium Ion Intermediates

Organic Letters

Volumn 3, Issue 3, 2001, Pages 425-428

  Myers, Andrew G ^a   Barbay, Joseph K ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CATION; KETONE; PROTEINASE INHIBITOR; VINYL DERIVATIVE;

ARTICLE; CHEMISTRY;

CATIONS; KETONES; PROTEASE INHIBITORS; VINYL COMPOUNDS;

EID: 0035825779     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol006931x     Document Type: Article

References (38)

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11. Myers, A. G.; Barbay, J. K.; Zhong, B. To be submitted for publication.
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24. For reviews of cycloaddition reactions involving oxyallyl cations, see: (a) Rigby, J. H.; Pigge, F. C. Org. React. 1997, 51, 351-478. (b) Hosomi, A.; Tominga, Y. In Comprehensive Organic Synthesis; Trost, B. M. Ed.; Pergamon Press: Oxford, 1991; Vol. 5, Chapter 5.1, pp 593-615. (c) Mann, J. Tetrahedron 1986, 42, 4611-4659. (d) Hoffman, H. M. R. Angew. Chem., Int. Ed. Engl. 1984, 23, 1-88. For the specific case of amido-substituted oxyallyl cations, see: (e) Walters, M. A.; Arcand, H. R. J. Org. Chem. 1996, 61, 1478-1486. (f) Walters, M. A.; Arcand, H. R.; Lawrie, D. J. Tetrahedron Lett. 1995, 36, 23-26.
25. For reviews of cycloaddition reactions involving oxyallyl cations, see: (a) Rigby, J. H.; Pigge, F. C. Org. React. 1997, 51, 351-478. (b) Hosomi, A.; Tominga, Y. In Comprehensive Organic Synthesis; Trost, B. M. Ed.; Pergamon Press: Oxford, 1991; Vol. 5, Chapter 5.1, pp 593-615. (c) Mann, J. Tetrahedron 1986, 42, 4611-4659. (d) Hoffman, H. M. R. Angew. Chem., Int. Ed. Engl. 1984, 23, 1-88. For the specific case of amido-substituted oxyallyl cations, see: (e) Walters, M. A.; Arcand, H. R. J. Org. Chem. 1996, 61, 1478-1486. (f) Walters, M. A.; Arcand, H. R.; Lawrie, D. J. Tetrahedron Lett. 1995, 36, 23-26.
26. For reviews of cycloaddition reactions involving oxyallyl cations, see: (a) Rigby, J. H.; Pigge, F. C. Org. React. 1997, 51, 351-478. (b) Hosomi, A.; Tominga, Y. In Comprehensive Organic Synthesis; Trost, B. M. Ed.; Pergamon Press: Oxford, 1991; Vol. 5, Chapter 5.1, pp 593-615. (c) Mann, J. Tetrahedron 1986, 42, 4611-4659. (d) Hoffman, H. M. R. Angew. Chem., Int. Ed. Engl. 1984, 23, 1-88. For the specific case of amido-substituted oxyallyl cations, see: (e) Walters, M. A.; Arcand, H. R. J. Org. Chem. 1996, 61, 1478-1486. (f) Walters, M. A.; Arcand, H. R.; Lawrie, D. J. Tetrahedron Lett. 1995, 36, 23-26.
27. For reviews of cycloaddition reactions involving oxyallyl cations, see: (a) Rigby, J. H.; Pigge, F. C. Org. React. 1997, 51, 351-478. (b) Hosomi, A.; Tominga, Y. In Comprehensive Organic Synthesis; Trost, B. M. Ed.; Pergamon Press: Oxford, 1991; Vol. 5, Chapter 5.1, pp 593-615. (c) Mann, J. Tetrahedron 1986, 42, 4611-4659. (d) Hoffman, H. M. R. Angew. Chem., Int. Ed. Engl. 1984, 23, 1-88. For the specific case of amido-substituted oxyallyl cations, see: (e) Walters, M. A.; Arcand, H. R. J. Org. Chem. 1996, 61, 1478-1486. (f) Walters, M. A.; Arcand, H. R.; Lawrie, D. J. Tetrahedron Lett. 1995, 36, 23-26.
28. For reviews of cycloaddition reactions involving oxyallyl cations, see: (a) Rigby, J. H.; Pigge, F. C. Org. React. 1997, 51, 351-478. (b) Hosomi, A.; Tominga, Y. In Comprehensive Organic Synthesis; Trost, B. M. Ed.; Pergamon Press: Oxford, 1991; Vol. 5, Chapter 5.1, pp 593-615. (c) Mann, J. Tetrahedron 1986, 42, 4611-4659. (d) Hoffman, H. M. R. Angew. Chem., Int. Ed. Engl. 1984, 23, 1-88. For the specific case of amido-substituted oxyallyl cations, see: (e) Walters, M. A.; Arcand, H. R. J. Org. Chem. 1996, 61, 1478-1486. (f) Walters, M. A.; Arcand, H. R.; Lawrie, D. J. Tetrahedron Lett. 1995, 36, 23-26.
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31. 3N system has been previously employed in cycloadditions of oxyallylic cations: Föhlisch, B.; Gehrlach, E.; Herter, R. Angew. Chem., Int. Ed. Engl. 1982, 2, 137.
32. The four diastereomeric cycloadducts were separable by silica gel chromatography. The relative stereochemistry of the centers within the bicyclo[3.2.1]octenone ring system in each product was assigned on the basis of observed NOESY cross-peaks.
33. Peet, N. P.; Burkhart, J. P.; Angelastro, M. R.; Giroux, E. L.; Mehdi, S.; Bey, P.; Kolb, M. K.; Neises, B.; Schirlin, D. J. Med. Chem. 1990, 33, 394-407.
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36. For another example of a stable α-amino α′-monofluoro ketone, see: Blanco, M.-J.; Sardina, F. J. J. Org. Chem. 1996, 61, 4748-4755.
37. See, for example: (a) Angelastro, M. R.; Burkhart, J. P.; Bey, P.; Peet, N. P. Tetrahedron Lett. 1992, 33, 3265-3268. (b) Dancer, J. E.; Ford, M. J.; Hamilton, K.; Kilkelly, M.; Lindell, S. D.; O'Mahony, M. J.; Saville-Stones, E. A. Bioorg. Med. Chem. Lett. 1996, 6, 2131-2136.
38. See, for example: (a) Angelastro, M. R.; Burkhart, J. P.; Bey, P.; Peet, N. P. Tetrahedron Lett. 1992, 33, 3265-3268. (b) Dancer, J. E.; Ford, M. J.; Hamilton, K.; Kilkelly, M.; Lindell, S. D.; O'Mahony, M. J.; Saville-Stones, E. A. Bioorg. Med. Chem. Lett. 1996, 6, 2131-2136.