Stereoselective Synthesis of Spirophosphoranes with a Phosphorus—Carbon Bond Based on 2‐(2‐Acetylphenoxy)benzo‐1,3,2‐dioxaphosphole.

The reactions of 2-(2-acetylphenoxy)benzo-1,3,2-dioxaphosphole containing the carbonyl group in the δ position with respect to the phosphorus atom with chloral and hexafluoroacetone afford tricyclic spirophosphoranes containing a phosphorus—carbon bond with high regio and stereoselectivity. The structures of the spirophosphoranes were established by X-ray diffraction.