How is methyl 4-hydroxyoxane-4-carboxylate (CAS: 115996-72-0) typically synthesized?

Methyl 4-hydroxyoxane-4-carboxylate (CAS: 115996-72-0) is typically synthesized through the condensation of methyl 4-chloroxane-1,2-dicarboxylate with sodium hydride in a solvent such as dimethylformamide (DMF). The reaction involves the displacement of the chlorine atom with a hydroxyl group, yielding the desired product in good yield. This synthesis is conducted under anhydrous conditions to prevent side reactions.