Chiral dienolate chemistry in remote asymmetric induction: The asymmetric aldol/oxy-Cope strategy for asymmetric synthesis of γ,δ-dichiral α,β-unsaturated acid derivatives

Tetrahedron Letters

Volumn 37, Issue 49, 1996, Pages 8899-8900

  Tomooka, Katsuhiko ^a   Nagasawa, Atsushi ^a   Wei, Shih Yi ^a   Nakai, Takeshi ^a  

^a TOKYO INSTITUTE OF TECHNOLOGY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

ALKENE DERIVATIVE; CARBOXYLIC ACID DERIVATIVE;

ARTICLE; DRUG SYNTHESIS; REACTION ANALYSIS; STEREOISOMERISM; TECHNIQUE;

EID: 0030566869     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(96)02078-3     Document Type: Article

References (10)

1. 1. Tomooka, K.; Nagasawa, A.; Wei, S.-Y.; Nakai, T., the preceding paper.
2. 2. This work was presented at the International Chemical Congress of Pacific Basin Societies, Honolulu, 1995, ORG100.
3. 3. Quite recently, a related work has been reported by the Merck Frosst group: Black, W. C.; Giroux, A.; Greidanus, G. Tetrahedron Lett. 1996, 37, 4471-4474. In their work, the aldol reactions of the boron dienolate derived from the crotonyl imide containing Evans' chiral auxiliary with various α,β-enals followed by the siloxy-Cope rearrangement have been shown to give the δ-chiral α,β-unsaturated imides in a high stereoselectivity. Note that in these cases the aldol adducts have no geometric problem.
4. 4. Imides 1a and 1b were prepared from (E)-2-and (E)-3-pentenoyl chloride, respectively, via reaction with (2R)-bornane-10,2-sultam according to the reported procedure: Oppolzer, W.; Blagg, J.; Rodriguez, I.; Walther, E. J. Am. Chem. Soc. 1990, 112, 2767-2772.
5. 1H NMR analysis (cf. ref 7).
6. 6. Review: Oppolzer, W. Tetrahedron 1987, 43, 1969-2004.
7. 3) δ 163.9 (NCO), 178.0 (HOOC).
8. 8. The "stereopurity" refers to the percentage of the major stereoisomer among all possible isomers.
9. 9. Fujita, Y.; Onishi, T.; Nishida, T. J. Chem. Soc., Chem. Commun. 1978, 972-973.
10. 10. Thies, R. W.; Wills, M. T.; Chin, A. W.; Schick, L. E.; Walton, E. S. J. Am. Chem. Soc. 1973, 95, 5281-5285.