Conicol, cascade reactions

Scheme 78 Three-component cascade reaction in the total synthesis of (+)-conicol (341)...

Hong and co-workers entirely exploited the ability of amine catalysts to promote cascade reactions by different mechanisms. They applied a one-pot oxa Michael-Michael-Michael-aldol reaction for the synthesis of conicol, a marine terpenoid isolated from Aplidium conicum (Scheme 11.32). Using diphenyl prolinol silyl ether 12,... 

Scheme 44.4 Total syntheses of (-t-)-conicol and (-fl-galbulin via cascade organocatalytic reactions.

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