Stereospecific total syntheses of 7α- and 7β-eremophilane-6-one and 7α- and 7β-eremophilane

✍ Scribed by Peter A. Jacobi; Roger F. Frechette

• Publisher: Elsevier Science
• Year: 1987
• Tongue: French
• Weight: 246 KB
• Volume: 28
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)96248-8

✦ Synopsis

Summan: The title compounds have been prepared in a highly eficientfashion by a synthetic route involving an intramolecular Diels-Alder reaction of an acetylenic thiazole followed by reductive modification of the resulting fused-ring thiophene.

13. Models indicate that the difference in selectivity observed for the Ra-Ni reduction of 3 and 13 is a result of the fact that both possible chair conformations of 3 favor g-approach of the catalyst, while the two chair conformations of 13 exhibit opposite facial selectivity.