Method for the Efficient Synthesis of Highly-Substituted Oxetan- and Azetidin-, Dihydrofuran- and Pyrrolidin-3-ones and Its Application to the Synthesis of (±)-Pseudodeflectusin

Highly substituted four- and five-membered heterocycles were prepared starting with O,P- and N,P-acetals by using a one-pot method involving base induced cyclization and a Horner-Wadsworth-Emmons (HWE) olefination reaction. Divergent synthesis of various heterocycles was achieved by using this method and transformations of the alkenyl group in the products of these processes were exemplified. Finally, a short and efficient synthesis of (±)-pseudodeflectusin based on the new methodology was achieved.