Synthesis Studies Of Daphlongamine E

Daphlongamine E is one of Calyciphylline Aalkaloids which was isolated from from the leaves of Daphniphyllum longeracemosum by professor Hao in 2009, it contains five-membered fused rings skeleton and six quaternary carbon center. Owing to its complex structure, the total synthesis of Daphlongamine E is proved to be very challenging.In this dissertation, a novel synthesis for five membered skeleton of Daphlongamine E was reported in 12 steps starting from the known compound 2-29 and 2-49, this synthesis features a phosphine-catalyzed [3 + 2]cycloaddition reaction?Curtius rearrangement reaction ? Intramolecular Aldol condensation reaction and oxidative rearrangement reaction of tertiary allylic alcohol by PCC, meanwhile lays a solid foundation for the total synthesis of Daphlongamine E.