The synthesis of the zaragozic acids: Equilibrium control of stereochemistry in the dioxabicyclo[3.2.1]octane core

Tetrahedron Letters

Volumn 38, Issue 25, 1997, Pages 4329-4332

  Hegde, Sayee G ^a   Myles, David C ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ACETAL; SQUALESTATIN;

ARTICLE; DRUG SYNTHESIS; ISOMERISM; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030963299     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)00966-0     Document Type: Article

References (26)

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18. This dianion was originally reported by E. J. Corey (Corey, E. J.; Widiger, G. N.; J. Org. Chem.. 1975, 40, 2975). We have found that the reliability with which the dianion is formed is greatly enhanced by carrying out the deprotonation with methyl magnesium bromide prior to halogen metal exchange with tert-butyllithium. Hegde, S. G.; Myles, D. C., Syn. Commun., 1997, in press.
19. This dianion was originally reported by E. J. Corey (Corey, E. J.; Widiger, G. N.; J. Org. Chem.. 1975, 40, 2975). We have found that the reliability with which the dianion is formed is greatly enhanced by carrying out the deprotonation with methyl magnesium bromide prior to halogen metal exchange with tert-butyllithium. Hegde, S. G.; Myles, D. C., Syn. Commun., 1997, in press.
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26. Close contacts between the C-3 proton and endo protons on carbons 6 and 7 established the structure of 16.