Julian Adams, C. Lepine‐Frenette, D. Spero
Jul 1, 1991
Citations
0
Influential Citations
21
Citations
Journal
Journal of Organic Chemistry
Abstract
The transannular cyclopropanation of a keto carbene generated by Rh 2 (OAc) 4 catalysis on a bicyclic dihydropyran nucleus provided a key oxatricyclic ketone intermediate for the synthesis of the [6.6] spirocyclic ring construction. Selective fragmentation of the cyclopropane followed by hydrolytic cleavage of the C−O bond provided the spirocyclic skeleton. Functional group manipulations to adjust oxidation states led to a total synthesis of (±)-β-chamigrene in 14 steps without the use of protection/deprotection schemes