Generation of 1-Amidoalkyl Radicals from N-Protected Amino Acids: An Alternative to the Barton Decarboxylation Procedure

Synlett

Volumn 1997, Issue 2, 1997, Pages 181-182

  Stojanovic, Aleksandar ^a   Renaud, Philippe ^a  

^a UNIVERSITY OF FRIBOURG   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0003067028     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1997-727     Document Type: Article

References (21)

1. For a recent review, see: Renaud, P.; Giraud, L. Synthesis 1996, 913-926.
2. Linstead, R. R.; Shepard, B. R.; Weedon, B. C. L. J. Chem. Soc. 1951, 2854-2859.
3. Barton, D. H. R.; Hervé, Y.; Potier, P.; Thierry, J. Tetrahedron 1988, 44, 5479-5486.
4. The decarbonylation of acyl radicals derived from the selenoesters of N-protected amino acids has already been observed but never investigated for its synthetic potential: (a) Crich, D.; Eustace, K. A.; Ritchie, T. J. Heterocycles 1989, 28, 67-70. (b) Boger, D.; Mathvink, R. J. J. Org. Chem. 1992, 57, 1429-1443. During the writing of this manuscript, we became aware of a study of the decarbonylation of selenoesters derived from N-alkylated amino acids: (c) Quirante, J.; Escolano, C.; Bonjoch, J. Synlett, 1997, ??.
5. The decarbonylation of acyl radicals derived from the selenoesters of N-protected amino acids has already been observed but never investigated for its synthetic potential: (a) Crich, D.; Eustace, K. A.; Ritchie, T. J. Heterocycles 1989, 28, 67-70. (b) Boger, D.; Mathvink, R. J. J. Org. Chem. 1992, 57, 1429-1443. During the writing of this manuscript, we became aware of a study of the decarbonylation of selenoesters derived from N-alkylated amino acids: (c) Quirante, J.; Escolano, C.; Bonjoch, J. Synlett, 1997, ??.
6. The decarbonylation of acyl radicals derived from the selenoesters of N-protected amino acids has already been observed but never investigated for its synthetic potential: (a) Crich, D.; Eustace, K. A.; Ritchie, T. J. Heterocycles 1989, 28, 67-70. (b) Boger, D.; Mathvink, R. J. J. Org. Chem. 1992, 57, 1429-1443. During the writing of this manuscript, we became aware of a study of the decarbonylation of selenoesters derived from N-alkylated amino acids: (c) Quirante, J.; Escolano, C.; Bonjoch, J. Synlett, 1997, ??.
7. The reduction of α-oxygenated phenylselenoesters with tributyltin hydride is known to give decarbonylated products: Ireland, R.; Norbeck, D. W.; Mandel, G. S.; Mandel, N. S. J. Am. Chem. Soc. 1985, 107, 3285-3294. For other radical decarbonylations of phenylselenoesters, see: Pfenninger, J.; Heuberger, C.; Graf. W. Helv. Chim. Acta 1980, 63, 2328-2337. Pfenninger, J.; Graf, W. Helv. Chim. Acta 1980, 63, 1563-1581.
8. The reduction of α-oxygenated phenylselenoesters with tributyltin hydride is known to give decarbonylated products: Ireland, R.; Norbeck, D. W.; Mandel, G. S.; Mandel, N. S. J. Am. Chem. Soc. 1985, 107, 3285-3294. For other radical decarbonylations of phenylselenoesters, see: Pfenninger, J.; Heuberger, C.; Graf. W. Helv. Chim. Acta 1980, 63, 2328-2337. Pfenninger, J.; Graf, W. Helv. Chim. Acta 1980, 63, 1563-1581.
9. The reduction of α-oxygenated phenylselenoesters with tributyltin hydride is known to give decarbonylated products: Ireland, R.; Norbeck, D. W.; Mandel, G. S.; Mandel, N. S. J. Am. Chem. Soc. 1985, 107, 3285-3294. For other radical decarbonylations of phenylselenoesters, see: Pfenninger, J.; Heuberger, C.; Graf. W. Helv. Chim. Acta 1980, 63, 2328-2337. Pfenninger, J.; Graf, W. Helv. Chim. Acta 1980, 63, 1563-1581.
10. For some rate constants of decarbonylation of acyl radicals, see: Fischer, H.; Henning, P. Acc. Chem. Res. 1987, 20, 200-206.
11. Phthalimido substituted radicals have been shown to be unique for the control of the diastereoselectivity in acyclic systems: Damm, W.; Hoffmann, U.; Macko, L.; Neuburger, M.; Zehnder, M.; Giese, B. Tetrahedron 1994, 50, 7029-7048. Renaud, P.; Stojanovic, A. Tetrahedron Lett. 1996, 37, 2569-2572.
12. Phthalimido substituted radicals have been shown to be unique for the control of the diastereoselectivity in acyclic systems: Damm, W.; Hoffmann, U.; Macko, L.; Neuburger, M.; Zehnder, M.; Giese, B. Tetrahedron 1994, 50, 7029-7048. Renaud, P.; Stojanovic, A. Tetrahedron Lett. 1996, 37, 2569-2572.
13. Batty, D.; Crich, D. Synthesis 1990, 273-275.
14. Miyashita, M.; Hoshino, H.; Yoshikoshi, A. Tetrahedron Lett. 1988, 29, 347-350. Sharpless, K. B.; Lauer, R. F. J. Am. Chem. Soc. 1973, 95, 2697-2699.
15. Miyashita, M.; Hoshino, H.; Yoshikoshi, A. Tetrahedron Lett. 1988, 29, 347-350. Sharpless, K. B.; Lauer, R. F. J. Am. Chem. Soc. 1973, 95, 2697-2699.
16. Epimerization of the α-center was observed during the formation of the selenoester 10.
17. 2O, the crude product was purified by flash chromatography. Physical and spectral data of 11-13 were in good accordance with literature data: 11: Tanaka, K.-I.; Yoshifuji, S.; Nitta, Y. Chem. Pharm. Bull. 1988, 36, 3125-3129. 12: commercially available (Aldrich 12,375-7). 13: Trybulski, E. J.; Krammss, R. H.; Brabander, H. J. to American Cyanamid Co., Eur. Pat. 92-103491.
18. 2O, the crude product was purified by flash chromatography. Physical and spectral data of 11-13 were in good accordance with literature data: 11: Tanaka, K.-I.; Yoshifuji, S.; Nitta, Y. Chem. Pharm. Bull. 1988, 36, 3125-3129. 12: commercially available (Aldrich 12,375-7). 13: Trybulski, E. J.; Krammss, R. H.; Brabander, H. J. to American Cyanamid Co., Eur. Pat. 92-103491.
19. 2CHN); 0.81 (s, t-Bu); 0.01 and 0.00 (2 s, 2 Me).
20. Giese, B. Angew. Chem. Int. Ed. Engl. 1985, 24, 553-579.
21. 2-COOMe); 1.40 (s, t-Bu).