I. Studies towards the total synthesis of (+/-)-lycoramine. II. Development of the retro-aza-Claisen rearrangement to synthesize medium sized N-substituted heterocycles. III. Studies towards the total synthesis of (-)-nakadomarin A

I. Studies Towards the Total Synthesis of (+/-)-Lycoramine;The tricyclic core of the amaryllidaceae alkaloids was prepared in a convergent synthesis via an intramolecular Heck/phenol capture sequence. The versatile cascade reaction allows for a rapid assembly of numerous key intermediates that can be elaborated to give the necessary framework for the completion of the total synthesis of lycoramine.;II. Development of the Aza-Retro-Claisen Rearrangement to Synthesize - Medium Sized N-Substituted Heterocycles;An efficient synthesis of medium-sized heterocyclic rings was achieved using a one-pot aza-Wittig/retro-aza-Claisen sequence of vinyl cyclobutanecarbox-aldehydes derived from simple allylic carbonates. A range of Staudinger reagents in the aza-Wittig reaction were used to allow for a variety of N-substituted products to be obtained. The rearrangement is thermodynamically controlled though ring strain relief of the cyclobutane and resonance stabilization of the resulting vinylogous sufonamide.;III. Studies Towards the Total Synthesis of (-)-Nakadomarin A;The total synthesis of Nakadomarin A was pursued. An efficient asymmetric synthesis of a key bicyclic lactam precursor was completed based on previous research efforts. A series of model studies were completed in order to help understand the behavior of a 3-aza-6-pi-electrocyclic ring closure; a key steps in our synthetic strategy. In addition to the model studies, a variety of synthetic routes toward the completion of 2,4-substituted furfural cinnamaldehydes were undertaken, which was applied towards the completion of the synthetic effort.