How is 4-Chloro-4-phenyldihydro-2H-pyran-2,6(3H)-dione (CAS: 182955-12-0) typically synthesized?

4-Chloro-4-phenyldihydro-2H-pyran-2,6(3H)-dione (CAS: 182955-12-0) is typically synthesized via the reaction of 4-chloro-1,3-dioxolan-2-one with phenylmagnesium bromide followed by acid work-up. The reaction is catalyzed by a strong base such as sodium hydride, and yields approximately 80-85% of the desired product. The method is selective and efficient for obtaining the compound in high purity.