Current Target
A second synthesis project is based on the facile generation of a reactive alkylidene carbene intermediate 2 from combination of heteroatom anions with alkynyliodonium salts 1 (Fig. 1). This carbene intermediate participates in a range of subsequent intramolecular (and intermolecular) transformations, including rearrangement via 1,2-shift (path a), C-H insertion (path b), X-lone pair insertion (path c) and alkene cycloaddition (path d), to furnish a structurally diverse suite of products (Fig. 1), some of which are related to various families of naturally occurring target molecules. Examples of the reactions that have been developed to facilitate heterocycle preparation are shown in Fig. 2. Intramolecular delivery of the electrophilic carbene to its nucleophilic partner further expands the utility of these transformations in polycycle synthesis. Syntheses of the alkaloid cephalotaxine (the core structure of a class of antileukemic plant principles), the cytotoxic marine metabolite agelastatin A, and the polycyclic alkaloid magellaninone are current goals of this chemistry (Fig. 3).
Current Target
