Asymmetric Radical Cyclization Induced by a Matched Pair of Chiral Auxiliaries: Synthesis of a Chiral 1β-Methylcarbapenem Key Intermediate

Synlett

Volumn 1995, Issue 9, 1995, Pages 915-917

  Ishibashi, Hiroyuki ^a   Kameoka, Chisato ^a   Kodama, Kazuya ^a   Ikeda, Masazumi ^a  

^a KYOTO PHARMACEUTICAL UNIVERSITY   (Japan)

Author keywords

1 methylcarbapenem; asymmetric induction; Mitsunobu reaction; radical cyclization; ruthenium tetroxide oxidation

Indexed keywords

EID: 14444282312     PISSN: 09365214     EISSN: 14372096     Source Type: Journal    
DOI: 10.1055/s-1995-5144     Document Type: Article

References (10)

1. Shih, D. H.; Baker, F.; Cama, L.; Christensen, B. G. Heterocycles 1984, 21, 29.
2. Sakurai, O.; Ogiku, T.; Takahashi, M.; Horikawa, H.; Iwasaki, T. Tetrahedron Lett. 1994, 35, 2187.
3. Maruyama, T.; Yoshida, A.; Kobayashi, T.; Miura, T. Tetrahedron Lett. 1994, 35, 2271.
4. Choi, W.-B.; Churchill, H. R. O.; Lynch, J. E.; Thompson, A. S.; Humphrey, G. R.; Volante, R. P.; Reider, P. J.; Shinkai, I. Tetrahedron Lett. 1994, 35, 2275.
5. Jones, D. K.; Liotta, D. C.; Choi, W.-B.; Volante, R. P.; Reider, P. J.; Shinkai, I.; Churchill, H. R. O.; Lynch, J. E. J. Org. Chem. 1994, 59, 3749.
6. Th'ukada, N.; Shimada, T.; Gyoung, Y. S.; Asao, N.; Yamamoto, Y. Org. Chem. 1995, 60, 143.
7. Ishibashi, H.; Kodama, K.; Kameoka, C; Kawanami, H.; Ikeda, M. Synlett 1995, 912.
8. Ishibashi, H.; Kameoka, C; Iriyama, H.; Kodama, K.; Sato, T.; Ikeda, M. Org. Chem. 1995, 60, 1276
9. Compound 9 (55% yield) was prepared by condensation of 2-phenylpropionaldehyde with p-methoxybenzylamine followed by iV-Acylation of the resulting imine with 2-bromobutyryl bromide in refluxing benzene in the presence of iV^V-diethylaniline. In a manner similar to that described above, compounds 4 and 16 were prepared from the corresponding 2-Arylpropionaldehyde, (5)-(-)-l-phenylethylamine, and (2/?, 3S)-3-Acetoxy-2-bromo-butyryl choride4 in 62 and 92% yields, respectively. The EIZ ratio of 9 was shown to be ca. 3:2 by tH NMR spectroscopy, but those of 4 and 16 were unclear due to the presence of rotamers.
10. Analogous results that the nature of the N-substituent can have a profound effect on the conformation of the C-4 side chain of p-lactams (including reaction intermediates) have been reported. See: Refs 2d, 2e, and Kim, C. U.; Luh, B.; Partyka, R. Tetrahedron Lett. 1987, 28, 507.