Synthesis of Phenanthridine derivatives from Arynes and Ketimines via aza-Diels-Alder/decarboxylation reactions

The aza -Diels-Alder and decarboxylation reactions have been developed for the synthesis of a variety of functionalized phenanthridine . The approach by using ketimine and arynes constructed the phenanthridine core smoothly and efficiently. With this strategy, an expeditious total synthesis of the natural products trispheridine and nornitidine has been realized. • Polycyclic compound was constructed in one-step by using aryne as the key intermediate. • The natural products trispheridine and nornitidine could be constructed efficiently via the developed strategy. • Target product phenanthridines possess great potential to be transformed into derivatives with wide applications.