Catalytic, Asymmetric Indolizidinone Aza-Quaternary Stereocenter Synthesis: Expedient Synthesis of the Cylindricine Alkaloid Core
作者:Derek M. Dalton、Tomislav Rovis
DOI:10.1021/ol400529k
日期:2013.5.17
The Rh(I)•CKphos catalyzed [2 + 2 + 2] cycloaddition of 1,1-disubstituted alkenyl isocyanates and alkyl alkynes selectively forms previously inaccessible vinylogous amide indolizidinone cycloadducts, establishing an aza-quaternery stereocenter with excellent enantioselectivities (up to 98% ee). This advance enables a seven step catalytic, asymmetric synthesis of the tricyclic core of the cylindricine