Rearrangement approaches to sesquiterpenes containing multiple contiguous quaternary carbon atoms. Total synthesis of (±)-myltayl-8(12)-ene and (±)-6-epijunicedranol
作者:A. Srikrishna、C. V. Yelamaggad、P. Praveen Kumar
DOI:10.1039/a906706j
日期:——
Boron trifluoride–diethyl ether mediated cyclization and rearrangement transformed the dienones 12 and 18 into the tricyclic ketones 16 and 17, efficiently creating three and four contiguous quaternary carbon atoms, respectively. Wittig methylenation of 16 furnished (±)-myltayl-8(12)-ene (11), whereas reduction of the ketone 17 furnished (±)-6-epijunicedranol (23).
描述了倍半萜myltayl-8(12)-烯和6-epijunicedran-8-ol的第一批总合成的细节。通过对香叶醇的克莱森重排而获得的醛13被转化为二烯酮12和18。三氟化硼-二乙醚介导的环化和重排将二烯酮12和18转化为三环酮16和17,从而有效地形成了三个和四个连续的四元季铵盐。碳原子。16个提供的(±)-甲基甲基(8)(12)-烯(11)的Wittig亚甲基化,而酮17的还原提供的(±)-6-表己内酯(23)。