New Chiral Synthons for Efficient Introduction of Bispropionates via Stereospecific Oxonia-Cope Rearrangements

摘要

The synthesis of polypropionates,a common structural motif in many biologically active natural products,provides inspiration and impetus for exploring new carbon-carbon bond-forming reactions.Iterative aldol or crotylation transformations build polypropionate structures by forming every other carbon-carbon bond of a carbon chain,but more efficient processes use larger building blocks.In this communication,we report a novel approach to the Stereospecific introduction of bispropionate synthons in a non-aldol fashion,which utilizes Lewis acid catalysis rather than base-promoted conditions.