2896-98-2

6309-59-7

2896-98-2

General procedure for the synthesis of tetrahydro-1,4-thiopyran-5-one from tetrahydro-4H-thiopyran-4-one oxime: to an acetone/water (20 mL/20 mL) solution of compound 2 (1.0 g, 7.6 mmol) was added p-toluene sulfonyl chloride (TsCl, 2.16 g, 11.4 mmol) and sodium carbonate (Na2CO3, 1.2 g, 23.2 mmol). The reaction mixture was stirred at 60 °C for 16 hours. After completion of the reaction, the solvent was removed by concentration under reduced pressure. The residue was extracted with ethyl acetate (EA, 20 mL x 3). The organic layers were combined, dried over anhydrous sodium sulfate (Na2SO4), filtered and the filtrate was concentrated to give compound 3 (740 mg, 74% yield) as a white solid.