Sequential Tandem Transformations of Functionalized Diazanorbornenes: Facile Strategy towards Pentacyclic Frameworks with Multiple Stereocenters

Abstract

The design, synthesis, and comprehensive utilization of diazanorbornene systems incorporating a flexible hydroxy group are described. The Lewis acid catalyzed intramolecular rearrangement of these strained alkenes gave cyclopentannulated dihydro-2H-pyrans, whereas the intermolecular sequential Lewis acid/palladium-mediated reaction with o-iodoanilines gave pentacyclic frameworks through multiple bond formation (C–C, C–N, C–O).