Sodium Methoxide → Methyl 3-oxotetrahydrothiopyran-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

A 250-mL round bottomed flask was charged with methyl 4-(2-methoxy-2-oxo-ethyl)thiobutanoate (26 g, 126 mmol, 1 eq.), sodium methoxide (30 g, 25 w % in methanol, 139 mmol, 1.1 eq.) and toluene (100 ml). The resulting mixture was stirred at 80° C. overnight and then methanol was removed by distillation until the temperature of the reaction mixture rose to 106° C. After cooling to room temperature, the mixture was poured into a mixture of ice (100 g) and 12N HCl (20 mL). The organic layer was separated and the aqueous layer was extracted with dichloromethane (3×20 ml) and the combined organic layers were dried over Na2SO4. Removal of solvent under reduced pressure gave the title compound as an oil (19.3 g, 88% yield). The product thus obtained was forwarded to the next step without any further purification.

Provenance & Evidence