A Short Total Synthesis of (±)-Lycorane by a Sequential Intramolecular Acylal Cyclisation (IAC) and Intramolecular Heck Addition Reaction

An intramolecular acylal cyclisation (IAC) approach to the synthesis of a range of bicyclic heterocycles is reported. As an example of the utility of the IAC reaction, the methodology was applied in a protecting-group free five-step total synthesis of (±)-lycorane, incorporating a novel intramolecular Heck addition reaction to generate the pentacyclic core structure of the natural product in good yield