Diastereoselective Synthesis of P-Stereogenic Heterocycles via Enyne Ring-Closing Metathesis

A range of P-containing ene-diynes suitable for desymmetrization was prepared via a two-step process starting from phosphorus oxychloride. In the presence of the Hoveyda−Grubbs II catalyst, these substrates underwent diastereoselective enyne ring-closing metathesis leading to various synthetically useful P-stereogenic heterocycles featuring an exocyclic alkynyl group. These products are amenable to further functional manipulation.