Vinigrol, total synthesis

Anionic oxy-Cope rearrangement was also employed for the enantioselective total synthesis of compounds related to marine metabolites (equation 230)305 307, as well as for the preparation of diterpenoide vinigrol (equation 231)308 and cerorubenic acid-in... 

With the exciting validation of our expedient strategy to form the tetracyclic cage structure using the oxidative dearomatization/Diels-Alder approach followed by consecutive cyclizations, we were now in position to modify each component to best serve the needs to realize a successful total synthesis of vinigrol. 

This final product corresponded to a very late intermediate in the Baran synthesis, which was converted in two steps to vinigrol (3) through a Shapiro reaction." The interception of a late-stage intermediate in the Baran synthesis thus completed the formal total synthesis of the natural product. 

Scheme 12.33 Key steps in Baran s total synthesis of ( )-vinigrol.

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